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Linux/Documentation/virt/kvm/api.rst

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Diff markup

Differences between /Documentation/virt/kvm/api.rst (Architecture ppc) and /Documentation/virt/kvm/api.rst (Architecture alpha)


  1 .. SPDX-License-Identifier: GPL-2.0                 1 .. SPDX-License-Identifier: GPL-2.0
  2                                                     2 
  3 ==============================================      3 ===================================================================
  4 The Definitive KVM (Kernel-based Virtual Machi      4 The Definitive KVM (Kernel-based Virtual Machine) API Documentation
  5 ==============================================      5 ===================================================================
  6                                                     6 
  7 1. General description                              7 1. General description
  8 ======================                              8 ======================
  9                                                     9 
 10 The kvm API is a set of ioctls that are issued     10 The kvm API is a set of ioctls that are issued to control various aspects
 11 of a virtual machine.  The ioctls belong to th     11 of a virtual machine.  The ioctls belong to the following classes:
 12                                                    12 
 13  - System ioctls: These query and set global a     13  - System ioctls: These query and set global attributes which affect the
 14    whole kvm subsystem.  In addition a system      14    whole kvm subsystem.  In addition a system ioctl is used to create
 15    virtual machines.                               15    virtual machines.
 16                                                    16 
 17  - VM ioctls: These query and set attributes t     17  - VM ioctls: These query and set attributes that affect an entire virtual
 18    machine, for example memory layout.  In add     18    machine, for example memory layout.  In addition a VM ioctl is used to
 19    create virtual cpus (vcpus) and devices.        19    create virtual cpus (vcpus) and devices.
 20                                                    20 
 21    VM ioctls must be issued from the same proc     21    VM ioctls must be issued from the same process (address space) that was
 22    used to create the VM.                          22    used to create the VM.
 23                                                    23 
 24  - vcpu ioctls: These query and set attributes     24  - vcpu ioctls: These query and set attributes that control the operation
 25    of a single virtual cpu.                        25    of a single virtual cpu.
 26                                                    26 
 27    vcpu ioctls should be issued from the same      27    vcpu ioctls should be issued from the same thread that was used to create
 28    the vcpu, except for asynchronous vcpu ioct     28    the vcpu, except for asynchronous vcpu ioctl that are marked as such in
 29    the documentation.  Otherwise, the first io     29    the documentation.  Otherwise, the first ioctl after switching threads
 30    could see a performance impact.                 30    could see a performance impact.
 31                                                    31 
 32  - device ioctls: These query and set attribut     32  - device ioctls: These query and set attributes that control the operation
 33    of a single device.                             33    of a single device.
 34                                                    34 
 35    device ioctls must be issued from the same      35    device ioctls must be issued from the same process (address space) that
 36    was used to create the VM.                      36    was used to create the VM.
 37                                                    37 
 38 2. File descriptors                                38 2. File descriptors
 39 ===================                                39 ===================
 40                                                    40 
 41 The kvm API is centered around file descriptor     41 The kvm API is centered around file descriptors.  An initial
 42 open("/dev/kvm") obtains a handle to the kvm s     42 open("/dev/kvm") obtains a handle to the kvm subsystem; this handle
 43 can be used to issue system ioctls.  A KVM_CRE     43 can be used to issue system ioctls.  A KVM_CREATE_VM ioctl on this
 44 handle will create a VM file descriptor which      44 handle will create a VM file descriptor which can be used to issue VM
 45 ioctls.  A KVM_CREATE_VCPU or KVM_CREATE_DEVIC     45 ioctls.  A KVM_CREATE_VCPU or KVM_CREATE_DEVICE ioctl on a VM fd will
 46 create a virtual cpu or device and return a fi     46 create a virtual cpu or device and return a file descriptor pointing to
 47 the new resource.  Finally, ioctls on a vcpu o     47 the new resource.  Finally, ioctls on a vcpu or device fd can be used
 48 to control the vcpu or device.  For vcpus, thi     48 to control the vcpu or device.  For vcpus, this includes the important
 49 task of actually running guest code.               49 task of actually running guest code.
 50                                                    50 
 51 In general file descriptors can be migrated am     51 In general file descriptors can be migrated among processes by means
 52 of fork() and the SCM_RIGHTS facility of unix      52 of fork() and the SCM_RIGHTS facility of unix domain socket.  These
 53 kinds of tricks are explicitly not supported b     53 kinds of tricks are explicitly not supported by kvm.  While they will
 54 not cause harm to the host, their actual behav     54 not cause harm to the host, their actual behavior is not guaranteed by
 55 the API.  See "General description" for detail     55 the API.  See "General description" for details on the ioctl usage
 56 model that is supported by KVM.                    56 model that is supported by KVM.
 57                                                    57 
 58 It is important to note that although VM ioctl     58 It is important to note that although VM ioctls may only be issued from
 59 the process that created the VM, a VM's lifecy     59 the process that created the VM, a VM's lifecycle is associated with its
 60 file descriptor, not its creator (process).  I     60 file descriptor, not its creator (process).  In other words, the VM and
 61 its resources, *including the associated addre     61 its resources, *including the associated address space*, are not freed
 62 until the last reference to the VM's file desc     62 until the last reference to the VM's file descriptor has been released.
 63 For example, if fork() is issued after ioctl(K     63 For example, if fork() is issued after ioctl(KVM_CREATE_VM), the VM will
 64 not be freed until both the parent (original)      64 not be freed until both the parent (original) process and its child have
 65 put their references to the VM's file descript     65 put their references to the VM's file descriptor.
 66                                                    66 
 67 Because a VM's resources are not freed until t     67 Because a VM's resources are not freed until the last reference to its
 68 file descriptor is released, creating addition     68 file descriptor is released, creating additional references to a VM
 69 via fork(), dup(), etc... without careful cons     69 via fork(), dup(), etc... without careful consideration is strongly
 70 discouraged and may have unwanted side effects     70 discouraged and may have unwanted side effects, e.g. memory allocated
 71 by and on behalf of the VM's process may not b     71 by and on behalf of the VM's process may not be freed/unaccounted when
 72 the VM is shut down.                               72 the VM is shut down.
 73                                                    73 
 74                                                    74 
 75 3. Extensions                                      75 3. Extensions
 76 =============                                      76 =============
 77                                                    77 
 78 As of Linux 2.6.22, the KVM ABI has been stabi     78 As of Linux 2.6.22, the KVM ABI has been stabilized: no backward
 79 incompatible change are allowed.  However, the     79 incompatible change are allowed.  However, there is an extension
 80 facility that allows backward-compatible exten     80 facility that allows backward-compatible extensions to the API to be
 81 queried and used.                                  81 queried and used.
 82                                                    82 
 83 The extension mechanism is not based on the Li     83 The extension mechanism is not based on the Linux version number.
 84 Instead, kvm defines extension identifiers and     84 Instead, kvm defines extension identifiers and a facility to query
 85 whether a particular extension identifier is a     85 whether a particular extension identifier is available.  If it is, a
 86 set of ioctls is available for application use     86 set of ioctls is available for application use.
 87                                                    87 
 88                                                    88 
 89 4. API description                                 89 4. API description
 90 ==================                                 90 ==================
 91                                                    91 
 92 This section describes ioctls that can be used     92 This section describes ioctls that can be used to control kvm guests.
 93 For each ioctl, the following information is p     93 For each ioctl, the following information is provided along with a
 94 description:                                       94 description:
 95                                                    95 
 96   Capability:                                      96   Capability:
 97       which KVM extension provides this ioctl.     97       which KVM extension provides this ioctl.  Can be 'basic',
 98       which means that is will be provided by      98       which means that is will be provided by any kernel that supports
 99       API version 12 (see section 4.1), a KVM_     99       API version 12 (see section 4.1), a KVM_CAP_xyz constant, which
100       means availability needs to be checked w    100       means availability needs to be checked with KVM_CHECK_EXTENSION
101       (see section 4.4), or 'none' which means    101       (see section 4.4), or 'none' which means that while not all kernels
102       support this ioctl, there's no capabilit    102       support this ioctl, there's no capability bit to check its
103       availability: for kernels that don't sup    103       availability: for kernels that don't support the ioctl,
104       the ioctl returns -ENOTTY.                  104       the ioctl returns -ENOTTY.
105                                                   105 
106   Architectures:                                  106   Architectures:
107       which instruction set architectures prov    107       which instruction set architectures provide this ioctl.
108       x86 includes both i386 and x86_64.          108       x86 includes both i386 and x86_64.
109                                                   109 
110   Type:                                           110   Type:
111       system, vm, or vcpu.                        111       system, vm, or vcpu.
112                                                   112 
113   Parameters:                                     113   Parameters:
114       what parameters are accepted by the ioct    114       what parameters are accepted by the ioctl.
115                                                   115 
116   Returns:                                        116   Returns:
117       the return value.  General error numbers    117       the return value.  General error numbers (EBADF, ENOMEM, EINVAL)
118       are not detailed, but errors with specif    118       are not detailed, but errors with specific meanings are.
119                                                   119 
120                                                   120 
121 4.1 KVM_GET_API_VERSION                           121 4.1 KVM_GET_API_VERSION
122 -----------------------                           122 -----------------------
123                                                   123 
124 :Capability: basic                                124 :Capability: basic
125 :Architectures: all                               125 :Architectures: all
126 :Type: system ioctl                               126 :Type: system ioctl
127 :Parameters: none                                 127 :Parameters: none
128 :Returns: the constant KVM_API_VERSION (=12)      128 :Returns: the constant KVM_API_VERSION (=12)
129                                                   129 
130 This identifies the API version as the stable     130 This identifies the API version as the stable kvm API. It is not
131 expected that this number will change.  Howeve    131 expected that this number will change.  However, Linux 2.6.20 and
132 2.6.21 report earlier versions; these are not     132 2.6.21 report earlier versions; these are not documented and not
133 supported.  Applications should refuse to run     133 supported.  Applications should refuse to run if KVM_GET_API_VERSION
134 returns a value other than 12.  If this check     134 returns a value other than 12.  If this check passes, all ioctls
135 described as 'basic' will be available.           135 described as 'basic' will be available.
136                                                   136 
137                                                   137 
138 4.2 KVM_CREATE_VM                                 138 4.2 KVM_CREATE_VM
139 -----------------                                 139 -----------------
140                                                   140 
141 :Capability: basic                                141 :Capability: basic
142 :Architectures: all                               142 :Architectures: all
143 :Type: system ioctl                               143 :Type: system ioctl
144 :Parameters: machine type identifier (KVM_VM_*    144 :Parameters: machine type identifier (KVM_VM_*)
145 :Returns: a VM fd that can be used to control     145 :Returns: a VM fd that can be used to control the new virtual machine.
146                                                   146 
147 The new VM has no virtual cpus and no memory.     147 The new VM has no virtual cpus and no memory.
148 You probably want to use 0 as machine type.       148 You probably want to use 0 as machine type.
149                                                   149 
150 X86:                                              150 X86:
151 ^^^^                                              151 ^^^^
152                                                   152 
153 Supported X86 VM types can be queried via KVM_    153 Supported X86 VM types can be queried via KVM_CAP_VM_TYPES.
154                                                   154 
155 S390:                                             155 S390:
156 ^^^^^                                             156 ^^^^^
157                                                   157 
158 In order to create user controlled virtual mac    158 In order to create user controlled virtual machines on S390, check
159 KVM_CAP_S390_UCONTROL and use the flag KVM_VM_    159 KVM_CAP_S390_UCONTROL and use the flag KVM_VM_S390_UCONTROL as
160 privileged user (CAP_SYS_ADMIN).                  160 privileged user (CAP_SYS_ADMIN).
161                                                   161 
162 MIPS:                                             162 MIPS:
163 ^^^^^                                             163 ^^^^^
164                                                   164 
165 To use hardware assisted virtualization on MIP    165 To use hardware assisted virtualization on MIPS (VZ ASE) rather than
166 the default trap & emulate implementation (whi    166 the default trap & emulate implementation (which changes the virtual
167 memory layout to fit in user mode), check KVM_    167 memory layout to fit in user mode), check KVM_CAP_MIPS_VZ and use the
168 flag KVM_VM_MIPS_VZ.                              168 flag KVM_VM_MIPS_VZ.
169                                                   169 
170 ARM64:                                            170 ARM64:
171 ^^^^^^                                            171 ^^^^^^
172                                                   172 
173 On arm64, the physical address size for a VM (    173 On arm64, the physical address size for a VM (IPA Size limit) is limited
174 to 40bits by default. The limit can be configu    174 to 40bits by default. The limit can be configured if the host supports the
175 extension KVM_CAP_ARM_VM_IPA_SIZE. When suppor    175 extension KVM_CAP_ARM_VM_IPA_SIZE. When supported, use
176 KVM_VM_TYPE_ARM_IPA_SIZE(IPA_Bits) to set the     176 KVM_VM_TYPE_ARM_IPA_SIZE(IPA_Bits) to set the size in the machine type
177 identifier, where IPA_Bits is the maximum widt    177 identifier, where IPA_Bits is the maximum width of any physical
178 address used by the VM. The IPA_Bits is encode    178 address used by the VM. The IPA_Bits is encoded in bits[7-0] of the
179 machine type identifier.                          179 machine type identifier.
180                                                   180 
181 e.g, to configure a guest to use 48bit physica    181 e.g, to configure a guest to use 48bit physical address size::
182                                                   182 
183     vm_fd = ioctl(dev_fd, KVM_CREATE_VM, KVM_V    183     vm_fd = ioctl(dev_fd, KVM_CREATE_VM, KVM_VM_TYPE_ARM_IPA_SIZE(48));
184                                                   184 
185 The requested size (IPA_Bits) must be:            185 The requested size (IPA_Bits) must be:
186                                                   186 
187  ==   ========================================    187  ==   =========================================================
188   0   Implies default size, 40bits (for backwa    188   0   Implies default size, 40bits (for backward compatibility)
189   N   Implies N bits, where N is a positive in    189   N   Implies N bits, where N is a positive integer such that,
190       32 <= N <= Host_IPA_Limit                   190       32 <= N <= Host_IPA_Limit
191  ==   ========================================    191  ==   =========================================================
192                                                   192 
193 Host_IPA_Limit is the maximum possible value f    193 Host_IPA_Limit is the maximum possible value for IPA_Bits on the host and
194 is dependent on the CPU capability and the ker    194 is dependent on the CPU capability and the kernel configuration. The limit can
195 be retrieved using KVM_CAP_ARM_VM_IPA_SIZE of     195 be retrieved using KVM_CAP_ARM_VM_IPA_SIZE of the KVM_CHECK_EXTENSION
196 ioctl() at run-time.                              196 ioctl() at run-time.
197                                                   197 
198 Creation of the VM will fail if the requested     198 Creation of the VM will fail if the requested IPA size (whether it is
199 implicit or explicit) is unsupported on the ho    199 implicit or explicit) is unsupported on the host.
200                                                   200 
201 Please note that configuring the IPA size does    201 Please note that configuring the IPA size does not affect the capability
202 exposed by the guest CPUs in ID_AA64MMFR0_EL1[    202 exposed by the guest CPUs in ID_AA64MMFR0_EL1[PARange]. It only affects
203 size of the address translated by the stage2 l    203 size of the address translated by the stage2 level (guest physical to
204 host physical address translations).              204 host physical address translations).
205                                                   205 
206                                                   206 
207 4.3 KVM_GET_MSR_INDEX_LIST, KVM_GET_MSR_FEATUR    207 4.3 KVM_GET_MSR_INDEX_LIST, KVM_GET_MSR_FEATURE_INDEX_LIST
208 ----------------------------------------------    208 ----------------------------------------------------------
209                                                   209 
210 :Capability: basic, KVM_CAP_GET_MSR_FEATURES f    210 :Capability: basic, KVM_CAP_GET_MSR_FEATURES for KVM_GET_MSR_FEATURE_INDEX_LIST
211 :Architectures: x86                               211 :Architectures: x86
212 :Type: system ioctl                               212 :Type: system ioctl
213 :Parameters: struct kvm_msr_list (in/out)         213 :Parameters: struct kvm_msr_list (in/out)
214 :Returns: 0 on success; -1 on error               214 :Returns: 0 on success; -1 on error
215                                                   215 
216 Errors:                                           216 Errors:
217                                                   217 
218   ======     =================================    218   ======     ============================================================
219   EFAULT     the msr index list cannot be read    219   EFAULT     the msr index list cannot be read from or written to
220   E2BIG      the msr index list is too big to     220   E2BIG      the msr index list is too big to fit in the array specified by
221              the user.                            221              the user.
222   ======     =================================    222   ======     ============================================================
223                                                   223 
224 ::                                                224 ::
225                                                   225 
226   struct kvm_msr_list {                           226   struct kvm_msr_list {
227         __u32 nmsrs; /* number of msrs in entr    227         __u32 nmsrs; /* number of msrs in entries */
228         __u32 indices[0];                         228         __u32 indices[0];
229   };                                              229   };
230                                                   230 
231 The user fills in the size of the indices arra    231 The user fills in the size of the indices array in nmsrs, and in return
232 kvm adjusts nmsrs to reflect the actual number    232 kvm adjusts nmsrs to reflect the actual number of msrs and fills in the
233 indices array with their numbers.                 233 indices array with their numbers.
234                                                   234 
235 KVM_GET_MSR_INDEX_LIST returns the guest msrs     235 KVM_GET_MSR_INDEX_LIST returns the guest msrs that are supported.  The list
236 varies by kvm version and host processor, but     236 varies by kvm version and host processor, but does not change otherwise.
237                                                   237 
238 Note: if kvm indicates supports MCE (KVM_CAP_M    238 Note: if kvm indicates supports MCE (KVM_CAP_MCE), then the MCE bank MSRs are
239 not returned in the MSR list, as different vcp    239 not returned in the MSR list, as different vcpus can have a different number
240 of banks, as set via the KVM_X86_SETUP_MCE ioc    240 of banks, as set via the KVM_X86_SETUP_MCE ioctl.
241                                                   241 
242 KVM_GET_MSR_FEATURE_INDEX_LIST returns the lis    242 KVM_GET_MSR_FEATURE_INDEX_LIST returns the list of MSRs that can be passed
243 to the KVM_GET_MSRS system ioctl.  This lets u    243 to the KVM_GET_MSRS system ioctl.  This lets userspace probe host capabilities
244 and processor features that are exposed via MS    244 and processor features that are exposed via MSRs (e.g., VMX capabilities).
245 This list also varies by kvm version and host     245 This list also varies by kvm version and host processor, but does not change
246 otherwise.                                        246 otherwise.
247                                                   247 
248                                                   248 
249 4.4 KVM_CHECK_EXTENSION                           249 4.4 KVM_CHECK_EXTENSION
250 -----------------------                           250 -----------------------
251                                                   251 
252 :Capability: basic, KVM_CAP_CHECK_EXTENSION_VM    252 :Capability: basic, KVM_CAP_CHECK_EXTENSION_VM for vm ioctl
253 :Architectures: all                               253 :Architectures: all
254 :Type: system ioctl, vm ioctl                     254 :Type: system ioctl, vm ioctl
255 :Parameters: extension identifier (KVM_CAP_*)     255 :Parameters: extension identifier (KVM_CAP_*)
256 :Returns: 0 if unsupported; 1 (or some other p    256 :Returns: 0 if unsupported; 1 (or some other positive integer) if supported
257                                                   257 
258 The API allows the application to query about     258 The API allows the application to query about extensions to the core
259 kvm API.  Userspace passes an extension identi    259 kvm API.  Userspace passes an extension identifier (an integer) and
260 receives an integer that describes the extensi    260 receives an integer that describes the extension availability.
261 Generally 0 means no and 1 means yes, but some    261 Generally 0 means no and 1 means yes, but some extensions may report
262 additional information in the integer return v    262 additional information in the integer return value.
263                                                   263 
264 Based on their initialization different VMs ma    264 Based on their initialization different VMs may have different capabilities.
265 It is thus encouraged to use the vm ioctl to q    265 It is thus encouraged to use the vm ioctl to query for capabilities (available
266 with KVM_CAP_CHECK_EXTENSION_VM on the vm fd)     266 with KVM_CAP_CHECK_EXTENSION_VM on the vm fd)
267                                                   267 
268 4.5 KVM_GET_VCPU_MMAP_SIZE                        268 4.5 KVM_GET_VCPU_MMAP_SIZE
269 --------------------------                        269 --------------------------
270                                                   270 
271 :Capability: basic                                271 :Capability: basic
272 :Architectures: all                               272 :Architectures: all
273 :Type: system ioctl                               273 :Type: system ioctl
274 :Parameters: none                                 274 :Parameters: none
275 :Returns: size of vcpu mmap area, in bytes        275 :Returns: size of vcpu mmap area, in bytes
276                                                   276 
277 The KVM_RUN ioctl (cf.) communicates with user    277 The KVM_RUN ioctl (cf.) communicates with userspace via a shared
278 memory region.  This ioctl returns the size of    278 memory region.  This ioctl returns the size of that region.  See the
279 KVM_RUN documentation for details.                279 KVM_RUN documentation for details.
280                                                   280 
281 Besides the size of the KVM_RUN communication     281 Besides the size of the KVM_RUN communication region, other areas of
282 the VCPU file descriptor can be mmap-ed, inclu    282 the VCPU file descriptor can be mmap-ed, including:
283                                                   283 
284 - if KVM_CAP_COALESCED_MMIO is available, a pa    284 - if KVM_CAP_COALESCED_MMIO is available, a page at
285   KVM_COALESCED_MMIO_PAGE_OFFSET * PAGE_SIZE;     285   KVM_COALESCED_MMIO_PAGE_OFFSET * PAGE_SIZE; for historical reasons,
286   this page is included in the result of KVM_G    286   this page is included in the result of KVM_GET_VCPU_MMAP_SIZE.
287   KVM_CAP_COALESCED_MMIO is not documented yet    287   KVM_CAP_COALESCED_MMIO is not documented yet.
288                                                   288 
289 - if KVM_CAP_DIRTY_LOG_RING is available, a nu    289 - if KVM_CAP_DIRTY_LOG_RING is available, a number of pages at
290   KVM_DIRTY_LOG_PAGE_OFFSET * PAGE_SIZE.  For     290   KVM_DIRTY_LOG_PAGE_OFFSET * PAGE_SIZE.  For more information on
291   KVM_CAP_DIRTY_LOG_RING, see section 8.3.        291   KVM_CAP_DIRTY_LOG_RING, see section 8.3.
292                                                   292 
293                                                   293 
294 4.7 KVM_CREATE_VCPU                               294 4.7 KVM_CREATE_VCPU
295 -------------------                               295 -------------------
296                                                   296 
297 :Capability: basic                                297 :Capability: basic
298 :Architectures: all                               298 :Architectures: all
299 :Type: vm ioctl                                   299 :Type: vm ioctl
300 :Parameters: vcpu id (apic id on x86)             300 :Parameters: vcpu id (apic id on x86)
301 :Returns: vcpu fd on success, -1 on error         301 :Returns: vcpu fd on success, -1 on error
302                                                   302 
303 This API adds a vcpu to a virtual machine. No     303 This API adds a vcpu to a virtual machine. No more than max_vcpus may be added.
304 The vcpu id is an integer in the range [0, max    304 The vcpu id is an integer in the range [0, max_vcpu_id).
305                                                   305 
306 The recommended max_vcpus value can be retriev    306 The recommended max_vcpus value can be retrieved using the KVM_CAP_NR_VCPUS of
307 the KVM_CHECK_EXTENSION ioctl() at run-time.      307 the KVM_CHECK_EXTENSION ioctl() at run-time.
308 The maximum possible value for max_vcpus can b    308 The maximum possible value for max_vcpus can be retrieved using the
309 KVM_CAP_MAX_VCPUS of the KVM_CHECK_EXTENSION i    309 KVM_CAP_MAX_VCPUS of the KVM_CHECK_EXTENSION ioctl() at run-time.
310                                                   310 
311 If the KVM_CAP_NR_VCPUS does not exist, you sh    311 If the KVM_CAP_NR_VCPUS does not exist, you should assume that max_vcpus is 4
312 cpus max.                                         312 cpus max.
313 If the KVM_CAP_MAX_VCPUS does not exist, you s    313 If the KVM_CAP_MAX_VCPUS does not exist, you should assume that max_vcpus is
314 same as the value returned from KVM_CAP_NR_VCP    314 same as the value returned from KVM_CAP_NR_VCPUS.
315                                                   315 
316 The maximum possible value for max_vcpu_id can    316 The maximum possible value for max_vcpu_id can be retrieved using the
317 KVM_CAP_MAX_VCPU_ID of the KVM_CHECK_EXTENSION    317 KVM_CAP_MAX_VCPU_ID of the KVM_CHECK_EXTENSION ioctl() at run-time.
318                                                   318 
319 If the KVM_CAP_MAX_VCPU_ID does not exist, you    319 If the KVM_CAP_MAX_VCPU_ID does not exist, you should assume that max_vcpu_id
320 is the same as the value returned from KVM_CAP    320 is the same as the value returned from KVM_CAP_MAX_VCPUS.
321                                                   321 
322 On powerpc using book3s_hv mode, the vcpus are    322 On powerpc using book3s_hv mode, the vcpus are mapped onto virtual
323 threads in one or more virtual CPU cores.  (Th    323 threads in one or more virtual CPU cores.  (This is because the
324 hardware requires all the hardware threads in     324 hardware requires all the hardware threads in a CPU core to be in the
325 same partition.)  The KVM_CAP_PPC_SMT capabili    325 same partition.)  The KVM_CAP_PPC_SMT capability indicates the number
326 of vcpus per virtual core (vcore).  The vcore     326 of vcpus per virtual core (vcore).  The vcore id is obtained by
327 dividing the vcpu id by the number of vcpus pe    327 dividing the vcpu id by the number of vcpus per vcore.  The vcpus in a
328 given vcore will always be in the same physica    328 given vcore will always be in the same physical core as each other
329 (though that might be a different physical cor    329 (though that might be a different physical core from time to time).
330 Userspace can control the threading (SMT) mode    330 Userspace can control the threading (SMT) mode of the guest by its
331 allocation of vcpu ids.  For example, if users    331 allocation of vcpu ids.  For example, if userspace wants
332 single-threaded guest vcpus, it should make al    332 single-threaded guest vcpus, it should make all vcpu ids be a multiple
333 of the number of vcpus per vcore.                 333 of the number of vcpus per vcore.
334                                                   334 
335 For virtual cpus that have been created with S    335 For virtual cpus that have been created with S390 user controlled virtual
336 machines, the resulting vcpu fd can be memory     336 machines, the resulting vcpu fd can be memory mapped at page offset
337 KVM_S390_SIE_PAGE_OFFSET in order to obtain a     337 KVM_S390_SIE_PAGE_OFFSET in order to obtain a memory map of the virtual
338 cpu's hardware control block.                     338 cpu's hardware control block.
339                                                   339 
340                                                   340 
341 4.8 KVM_GET_DIRTY_LOG (vm ioctl)                  341 4.8 KVM_GET_DIRTY_LOG (vm ioctl)
342 --------------------------------                  342 --------------------------------
343                                                   343 
344 :Capability: basic                                344 :Capability: basic
345 :Architectures: all                               345 :Architectures: all
346 :Type: vm ioctl                                   346 :Type: vm ioctl
347 :Parameters: struct kvm_dirty_log (in/out)        347 :Parameters: struct kvm_dirty_log (in/out)
348 :Returns: 0 on success, -1 on error               348 :Returns: 0 on success, -1 on error
349                                                   349 
350 ::                                                350 ::
351                                                   351 
352   /* for KVM_GET_DIRTY_LOG */                     352   /* for KVM_GET_DIRTY_LOG */
353   struct kvm_dirty_log {                          353   struct kvm_dirty_log {
354         __u32 slot;                               354         __u32 slot;
355         __u32 padding;                            355         __u32 padding;
356         union {                                   356         union {
357                 void __user *dirty_bitmap; /*     357                 void __user *dirty_bitmap; /* one bit per page */
358                 __u64 padding;                    358                 __u64 padding;
359         };                                        359         };
360   };                                              360   };
361                                                   361 
362 Given a memory slot, return a bitmap containin    362 Given a memory slot, return a bitmap containing any pages dirtied
363 since the last call to this ioctl.  Bit 0 is t    363 since the last call to this ioctl.  Bit 0 is the first page in the
364 memory slot.  Ensure the entire structure is c    364 memory slot.  Ensure the entire structure is cleared to avoid padding
365 issues.                                           365 issues.
366                                                   366 
367 If KVM_CAP_MULTI_ADDRESS_SPACE is available, b    367 If KVM_CAP_MULTI_ADDRESS_SPACE is available, bits 16-31 of slot field specifies
368 the address space for which you want to return    368 the address space for which you want to return the dirty bitmap.  See
369 KVM_SET_USER_MEMORY_REGION for details on the     369 KVM_SET_USER_MEMORY_REGION for details on the usage of slot field.
370                                                   370 
371 The bits in the dirty bitmap are cleared befor    371 The bits in the dirty bitmap are cleared before the ioctl returns, unless
372 KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is enabled.     372 KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is enabled.  For more information,
373 see the description of the capability.            373 see the description of the capability.
374                                                   374 
375 Note that the Xen shared_info page, if configu    375 Note that the Xen shared_info page, if configured, shall always be assumed
376 to be dirty. KVM will not explicitly mark it s    376 to be dirty. KVM will not explicitly mark it such.
377                                                   377 
378                                                   378 
379 4.10 KVM_RUN                                      379 4.10 KVM_RUN
380 ------------                                      380 ------------
381                                                   381 
382 :Capability: basic                                382 :Capability: basic
383 :Architectures: all                               383 :Architectures: all
384 :Type: vcpu ioctl                                 384 :Type: vcpu ioctl
385 :Parameters: none                                 385 :Parameters: none
386 :Returns: 0 on success, -1 on error               386 :Returns: 0 on success, -1 on error
387                                                   387 
388 Errors:                                           388 Errors:
389                                                   389 
390   =======    =================================    390   =======    ==============================================================
391   EINTR      an unmasked signal is pending        391   EINTR      an unmasked signal is pending
392   ENOEXEC    the vcpu hasn't been initialized     392   ENOEXEC    the vcpu hasn't been initialized or the guest tried to execute
393              instructions from device memory (    393              instructions from device memory (arm64)
394   ENOSYS     data abort outside memslots with     394   ENOSYS     data abort outside memslots with no syndrome info and
395              KVM_CAP_ARM_NISV_TO_USER not enab    395              KVM_CAP_ARM_NISV_TO_USER not enabled (arm64)
396   EPERM      SVE feature set but not finalized    396   EPERM      SVE feature set but not finalized (arm64)
397   =======    =================================    397   =======    ==============================================================
398                                                   398 
399 This ioctl is used to run a guest virtual cpu.    399 This ioctl is used to run a guest virtual cpu.  While there are no
400 explicit parameters, there is an implicit para    400 explicit parameters, there is an implicit parameter block that can be
401 obtained by mmap()ing the vcpu fd at offset 0,    401 obtained by mmap()ing the vcpu fd at offset 0, with the size given by
402 KVM_GET_VCPU_MMAP_SIZE.  The parameter block i    402 KVM_GET_VCPU_MMAP_SIZE.  The parameter block is formatted as a 'struct
403 kvm_run' (see below).                             403 kvm_run' (see below).
404                                                   404 
405                                                   405 
406 4.11 KVM_GET_REGS                                 406 4.11 KVM_GET_REGS
407 -----------------                                 407 -----------------
408                                                   408 
409 :Capability: basic                                409 :Capability: basic
410 :Architectures: all except arm64                  410 :Architectures: all except arm64
411 :Type: vcpu ioctl                                 411 :Type: vcpu ioctl
412 :Parameters: struct kvm_regs (out)                412 :Parameters: struct kvm_regs (out)
413 :Returns: 0 on success, -1 on error               413 :Returns: 0 on success, -1 on error
414                                                   414 
415 Reads the general purpose registers from the v    415 Reads the general purpose registers from the vcpu.
416                                                   416 
417 ::                                                417 ::
418                                                   418 
419   /* x86 */                                       419   /* x86 */
420   struct kvm_regs {                               420   struct kvm_regs {
421         /* out (KVM_GET_REGS) / in (KVM_SET_RE    421         /* out (KVM_GET_REGS) / in (KVM_SET_REGS) */
422         __u64 rax, rbx, rcx, rdx;                 422         __u64 rax, rbx, rcx, rdx;
423         __u64 rsi, rdi, rsp, rbp;                 423         __u64 rsi, rdi, rsp, rbp;
424         __u64 r8,  r9,  r10, r11;                 424         __u64 r8,  r9,  r10, r11;
425         __u64 r12, r13, r14, r15;                 425         __u64 r12, r13, r14, r15;
426         __u64 rip, rflags;                        426         __u64 rip, rflags;
427   };                                              427   };
428                                                   428 
429   /* mips */                                      429   /* mips */
430   struct kvm_regs {                               430   struct kvm_regs {
431         /* out (KVM_GET_REGS) / in (KVM_SET_RE    431         /* out (KVM_GET_REGS) / in (KVM_SET_REGS) */
432         __u64 gpr[32];                            432         __u64 gpr[32];
433         __u64 hi;                                 433         __u64 hi;
434         __u64 lo;                                 434         __u64 lo;
435         __u64 pc;                                 435         __u64 pc;
436   };                                              436   };
437                                                   437 
438   /* LoongArch */                                 438   /* LoongArch */
439   struct kvm_regs {                               439   struct kvm_regs {
440         /* out (KVM_GET_REGS) / in (KVM_SET_RE    440         /* out (KVM_GET_REGS) / in (KVM_SET_REGS) */
441         unsigned long gpr[32];                    441         unsigned long gpr[32];
442         unsigned long pc;                         442         unsigned long pc;
443   };                                              443   };
444                                                   444 
445                                                   445 
446 4.12 KVM_SET_REGS                                 446 4.12 KVM_SET_REGS
447 -----------------                                 447 -----------------
448                                                   448 
449 :Capability: basic                                449 :Capability: basic
450 :Architectures: all except arm64                  450 :Architectures: all except arm64
451 :Type: vcpu ioctl                                 451 :Type: vcpu ioctl
452 :Parameters: struct kvm_regs (in)                 452 :Parameters: struct kvm_regs (in)
453 :Returns: 0 on success, -1 on error               453 :Returns: 0 on success, -1 on error
454                                                   454 
455 Writes the general purpose registers into the     455 Writes the general purpose registers into the vcpu.
456                                                   456 
457 See KVM_GET_REGS for the data structure.          457 See KVM_GET_REGS for the data structure.
458                                                   458 
459                                                   459 
460 4.13 KVM_GET_SREGS                                460 4.13 KVM_GET_SREGS
461 ------------------                                461 ------------------
462                                                   462 
463 :Capability: basic                                463 :Capability: basic
464 :Architectures: x86, ppc                          464 :Architectures: x86, ppc
465 :Type: vcpu ioctl                                 465 :Type: vcpu ioctl
466 :Parameters: struct kvm_sregs (out)               466 :Parameters: struct kvm_sregs (out)
467 :Returns: 0 on success, -1 on error               467 :Returns: 0 on success, -1 on error
468                                                   468 
469 Reads special registers from the vcpu.            469 Reads special registers from the vcpu.
470                                                   470 
471 ::                                                471 ::
472                                                   472 
473   /* x86 */                                       473   /* x86 */
474   struct kvm_sregs {                              474   struct kvm_sregs {
475         struct kvm_segment cs, ds, es, fs, gs,    475         struct kvm_segment cs, ds, es, fs, gs, ss;
476         struct kvm_segment tr, ldt;               476         struct kvm_segment tr, ldt;
477         struct kvm_dtable gdt, idt;               477         struct kvm_dtable gdt, idt;
478         __u64 cr0, cr2, cr3, cr4, cr8;            478         __u64 cr0, cr2, cr3, cr4, cr8;
479         __u64 efer;                               479         __u64 efer;
480         __u64 apic_base;                          480         __u64 apic_base;
481         __u64 interrupt_bitmap[(KVM_NR_INTERRU    481         __u64 interrupt_bitmap[(KVM_NR_INTERRUPTS + 63) / 64];
482   };                                              482   };
483                                                   483 
484   /* ppc -- see arch/powerpc/include/uapi/asm/    484   /* ppc -- see arch/powerpc/include/uapi/asm/kvm.h */
485                                                   485 
486 interrupt_bitmap is a bitmap of pending extern    486 interrupt_bitmap is a bitmap of pending external interrupts.  At most
487 one bit may be set.  This interrupt has been a    487 one bit may be set.  This interrupt has been acknowledged by the APIC
488 but not yet injected into the cpu core.           488 but not yet injected into the cpu core.
489                                                   489 
490                                                   490 
491 4.14 KVM_SET_SREGS                                491 4.14 KVM_SET_SREGS
492 ------------------                                492 ------------------
493                                                   493 
494 :Capability: basic                                494 :Capability: basic
495 :Architectures: x86, ppc                          495 :Architectures: x86, ppc
496 :Type: vcpu ioctl                                 496 :Type: vcpu ioctl
497 :Parameters: struct kvm_sregs (in)                497 :Parameters: struct kvm_sregs (in)
498 :Returns: 0 on success, -1 on error               498 :Returns: 0 on success, -1 on error
499                                                   499 
500 Writes special registers into the vcpu.  See K    500 Writes special registers into the vcpu.  See KVM_GET_SREGS for the
501 data structures.                                  501 data structures.
502                                                   502 
503                                                   503 
504 4.15 KVM_TRANSLATE                                504 4.15 KVM_TRANSLATE
505 ------------------                                505 ------------------
506                                                   506 
507 :Capability: basic                                507 :Capability: basic
508 :Architectures: x86                               508 :Architectures: x86
509 :Type: vcpu ioctl                                 509 :Type: vcpu ioctl
510 :Parameters: struct kvm_translation (in/out)      510 :Parameters: struct kvm_translation (in/out)
511 :Returns: 0 on success, -1 on error               511 :Returns: 0 on success, -1 on error
512                                                   512 
513 Translates a virtual address according to the     513 Translates a virtual address according to the vcpu's current address
514 translation mode.                                 514 translation mode.
515                                                   515 
516 ::                                                516 ::
517                                                   517 
518   struct kvm_translation {                        518   struct kvm_translation {
519         /* in */                                  519         /* in */
520         __u64 linear_address;                     520         __u64 linear_address;
521                                                   521 
522         /* out */                                 522         /* out */
523         __u64 physical_address;                   523         __u64 physical_address;
524         __u8  valid;                              524         __u8  valid;
525         __u8  writeable;                          525         __u8  writeable;
526         __u8  usermode;                           526         __u8  usermode;
527         __u8  pad[5];                             527         __u8  pad[5];
528   };                                              528   };
529                                                   529 
530                                                   530 
531 4.16 KVM_INTERRUPT                                531 4.16 KVM_INTERRUPT
532 ------------------                                532 ------------------
533                                                   533 
534 :Capability: basic                                534 :Capability: basic
535 :Architectures: x86, ppc, mips, riscv, loongar    535 :Architectures: x86, ppc, mips, riscv, loongarch
536 :Type: vcpu ioctl                                 536 :Type: vcpu ioctl
537 :Parameters: struct kvm_interrupt (in)            537 :Parameters: struct kvm_interrupt (in)
538 :Returns: 0 on success, negative on failure.      538 :Returns: 0 on success, negative on failure.
539                                                   539 
540 Queues a hardware interrupt vector to be injec    540 Queues a hardware interrupt vector to be injected.
541                                                   541 
542 ::                                                542 ::
543                                                   543 
544   /* for KVM_INTERRUPT */                         544   /* for KVM_INTERRUPT */
545   struct kvm_interrupt {                          545   struct kvm_interrupt {
546         /* in */                                  546         /* in */
547         __u32 irq;                                547         __u32 irq;
548   };                                              548   };
549                                                   549 
550 X86:                                              550 X86:
551 ^^^^                                              551 ^^^^
552                                                   552 
553 :Returns:                                         553 :Returns:
554                                                   554 
555         ========= ============================    555         ========= ===================================
556           0       on success,                     556           0       on success,
557          -EEXIST  if an interrupt is already e    557          -EEXIST  if an interrupt is already enqueued
558          -EINVAL  the irq number is invalid       558          -EINVAL  the irq number is invalid
559          -ENXIO   if the PIC is in the kernel     559          -ENXIO   if the PIC is in the kernel
560          -EFAULT  if the pointer is invalid       560          -EFAULT  if the pointer is invalid
561         ========= ============================    561         ========= ===================================
562                                                   562 
563 Note 'irq' is an interrupt vector, not an inte    563 Note 'irq' is an interrupt vector, not an interrupt pin or line. This
564 ioctl is useful if the in-kernel PIC is not us    564 ioctl is useful if the in-kernel PIC is not used.
565                                                   565 
566 PPC:                                              566 PPC:
567 ^^^^                                              567 ^^^^
568                                                   568 
569 Queues an external interrupt to be injected. T    569 Queues an external interrupt to be injected. This ioctl is overloaded
570 with 3 different irq values:                      570 with 3 different irq values:
571                                                   571 
572 a) KVM_INTERRUPT_SET                              572 a) KVM_INTERRUPT_SET
573                                                   573 
574    This injects an edge type external interrup    574    This injects an edge type external interrupt into the guest once it's ready
575    to receive interrupts. When injected, the i    575    to receive interrupts. When injected, the interrupt is done.
576                                                   576 
577 b) KVM_INTERRUPT_UNSET                            577 b) KVM_INTERRUPT_UNSET
578                                                   578 
579    This unsets any pending interrupt.             579    This unsets any pending interrupt.
580                                                   580 
581    Only available with KVM_CAP_PPC_UNSET_IRQ.     581    Only available with KVM_CAP_PPC_UNSET_IRQ.
582                                                   582 
583 c) KVM_INTERRUPT_SET_LEVEL                        583 c) KVM_INTERRUPT_SET_LEVEL
584                                                   584 
585    This injects a level type external interrup    585    This injects a level type external interrupt into the guest context. The
586    interrupt stays pending until a specific io    586    interrupt stays pending until a specific ioctl with KVM_INTERRUPT_UNSET
587    is triggered.                                  587    is triggered.
588                                                   588 
589    Only available with KVM_CAP_PPC_IRQ_LEVEL.     589    Only available with KVM_CAP_PPC_IRQ_LEVEL.
590                                                   590 
591 Note that any value for 'irq' other than the o    591 Note that any value for 'irq' other than the ones stated above is invalid
592 and incurs unexpected behavior.                   592 and incurs unexpected behavior.
593                                                   593 
594 This is an asynchronous vcpu ioctl and can be     594 This is an asynchronous vcpu ioctl and can be invoked from any thread.
595                                                   595 
596 MIPS:                                             596 MIPS:
597 ^^^^^                                             597 ^^^^^
598                                                   598 
599 Queues an external interrupt to be injected in    599 Queues an external interrupt to be injected into the virtual CPU. A negative
600 interrupt number dequeues the interrupt.          600 interrupt number dequeues the interrupt.
601                                                   601 
602 This is an asynchronous vcpu ioctl and can be     602 This is an asynchronous vcpu ioctl and can be invoked from any thread.
603                                                   603 
604 RISC-V:                                           604 RISC-V:
605 ^^^^^^^                                           605 ^^^^^^^
606                                                   606 
607 Queues an external interrupt to be injected in    607 Queues an external interrupt to be injected into the virtual CPU. This ioctl
608 is overloaded with 2 different irq values:        608 is overloaded with 2 different irq values:
609                                                   609 
610 a) KVM_INTERRUPT_SET                              610 a) KVM_INTERRUPT_SET
611                                                   611 
612    This sets external interrupt for a virtual     612    This sets external interrupt for a virtual CPU and it will receive
613    once it is ready.                              613    once it is ready.
614                                                   614 
615 b) KVM_INTERRUPT_UNSET                            615 b) KVM_INTERRUPT_UNSET
616                                                   616 
617    This clears pending external interrupt for     617    This clears pending external interrupt for a virtual CPU.
618                                                   618 
619 This is an asynchronous vcpu ioctl and can be     619 This is an asynchronous vcpu ioctl and can be invoked from any thread.
620                                                   620 
621 LOONGARCH:                                        621 LOONGARCH:
622 ^^^^^^^^^^                                        622 ^^^^^^^^^^
623                                                   623 
624 Queues an external interrupt to be injected in    624 Queues an external interrupt to be injected into the virtual CPU. A negative
625 interrupt number dequeues the interrupt.          625 interrupt number dequeues the interrupt.
626                                                   626 
627 This is an asynchronous vcpu ioctl and can be     627 This is an asynchronous vcpu ioctl and can be invoked from any thread.
628                                                   628 
629                                                   629 
630 4.18 KVM_GET_MSRS                                 630 4.18 KVM_GET_MSRS
631 -----------------                                 631 -----------------
632                                                   632 
633 :Capability: basic (vcpu), KVM_CAP_GET_MSR_FEA    633 :Capability: basic (vcpu), KVM_CAP_GET_MSR_FEATURES (system)
634 :Architectures: x86                               634 :Architectures: x86
635 :Type: system ioctl, vcpu ioctl                   635 :Type: system ioctl, vcpu ioctl
636 :Parameters: struct kvm_msrs (in/out)             636 :Parameters: struct kvm_msrs (in/out)
637 :Returns: number of msrs successfully returned    637 :Returns: number of msrs successfully returned;
638           -1 on error                             638           -1 on error
639                                                   639 
640 When used as a system ioctl:                      640 When used as a system ioctl:
641 Reads the values of MSR-based features that ar    641 Reads the values of MSR-based features that are available for the VM.  This
642 is similar to KVM_GET_SUPPORTED_CPUID, but it     642 is similar to KVM_GET_SUPPORTED_CPUID, but it returns MSR indices and values.
643 The list of msr-based features can be obtained    643 The list of msr-based features can be obtained using KVM_GET_MSR_FEATURE_INDEX_LIST
644 in a system ioctl.                                644 in a system ioctl.
645                                                   645 
646 When used as a vcpu ioctl:                        646 When used as a vcpu ioctl:
647 Reads model-specific registers from the vcpu.     647 Reads model-specific registers from the vcpu.  Supported msr indices can
648 be obtained using KVM_GET_MSR_INDEX_LIST in a     648 be obtained using KVM_GET_MSR_INDEX_LIST in a system ioctl.
649                                                   649 
650 ::                                                650 ::
651                                                   651 
652   struct kvm_msrs {                               652   struct kvm_msrs {
653         __u32 nmsrs; /* number of msrs in entr    653         __u32 nmsrs; /* number of msrs in entries */
654         __u32 pad;                                654         __u32 pad;
655                                                   655 
656         struct kvm_msr_entry entries[0];          656         struct kvm_msr_entry entries[0];
657   };                                              657   };
658                                                   658 
659   struct kvm_msr_entry {                          659   struct kvm_msr_entry {
660         __u32 index;                              660         __u32 index;
661         __u32 reserved;                           661         __u32 reserved;
662         __u64 data;                               662         __u64 data;
663   };                                              663   };
664                                                   664 
665 Application code should set the 'nmsrs' member    665 Application code should set the 'nmsrs' member (which indicates the
666 size of the entries array) and the 'index' mem    666 size of the entries array) and the 'index' member of each array entry.
667 kvm will fill in the 'data' member.               667 kvm will fill in the 'data' member.
668                                                   668 
669                                                   669 
670 4.19 KVM_SET_MSRS                                 670 4.19 KVM_SET_MSRS
671 -----------------                                 671 -----------------
672                                                   672 
673 :Capability: basic                                673 :Capability: basic
674 :Architectures: x86                               674 :Architectures: x86
675 :Type: vcpu ioctl                                 675 :Type: vcpu ioctl
676 :Parameters: struct kvm_msrs (in)                 676 :Parameters: struct kvm_msrs (in)
677 :Returns: number of msrs successfully set (see    677 :Returns: number of msrs successfully set (see below), -1 on error
678                                                   678 
679 Writes model-specific registers to the vcpu.      679 Writes model-specific registers to the vcpu.  See KVM_GET_MSRS for the
680 data structures.                                  680 data structures.
681                                                   681 
682 Application code should set the 'nmsrs' member    682 Application code should set the 'nmsrs' member (which indicates the
683 size of the entries array), and the 'index' an    683 size of the entries array), and the 'index' and 'data' members of each
684 array entry.                                      684 array entry.
685                                                   685 
686 It tries to set the MSRs in array entries[] on    686 It tries to set the MSRs in array entries[] one by one. If setting an MSR
687 fails, e.g., due to setting reserved bits, the    687 fails, e.g., due to setting reserved bits, the MSR isn't supported/emulated
688 by KVM, etc..., it stops processing the MSR li    688 by KVM, etc..., it stops processing the MSR list and returns the number of
689 MSRs that have been set successfully.             689 MSRs that have been set successfully.
690                                                   690 
691                                                   691 
692 4.20 KVM_SET_CPUID                                692 4.20 KVM_SET_CPUID
693 ------------------                                693 ------------------
694                                                   694 
695 :Capability: basic                                695 :Capability: basic
696 :Architectures: x86                               696 :Architectures: x86
697 :Type: vcpu ioctl                                 697 :Type: vcpu ioctl
698 :Parameters: struct kvm_cpuid (in)                698 :Parameters: struct kvm_cpuid (in)
699 :Returns: 0 on success, -1 on error               699 :Returns: 0 on success, -1 on error
700                                                   700 
701 Defines the vcpu responses to the cpuid instru    701 Defines the vcpu responses to the cpuid instruction.  Applications
702 should use the KVM_SET_CPUID2 ioctl if availab    702 should use the KVM_SET_CPUID2 ioctl if available.
703                                                   703 
704 Caveat emptor:                                    704 Caveat emptor:
705   - If this IOCTL fails, KVM gives no guarante    705   - If this IOCTL fails, KVM gives no guarantees that previous valid CPUID
706     configuration (if there is) is not corrupt    706     configuration (if there is) is not corrupted. Userspace can get a copy
707     of the resulting CPUID configuration throu    707     of the resulting CPUID configuration through KVM_GET_CPUID2 in case.
708   - Using KVM_SET_CPUID{,2} after KVM_RUN, i.e    708   - Using KVM_SET_CPUID{,2} after KVM_RUN, i.e. changing the guest vCPU model
709     after running the guest, may cause guest i    709     after running the guest, may cause guest instability.
710   - Using heterogeneous CPUID configurations,     710   - Using heterogeneous CPUID configurations, modulo APIC IDs, topology, etc...
711     may cause guest instability.                  711     may cause guest instability.
712                                                   712 
713 ::                                                713 ::
714                                                   714 
715   struct kvm_cpuid_entry {                        715   struct kvm_cpuid_entry {
716         __u32 function;                           716         __u32 function;
717         __u32 eax;                                717         __u32 eax;
718         __u32 ebx;                                718         __u32 ebx;
719         __u32 ecx;                                719         __u32 ecx;
720         __u32 edx;                                720         __u32 edx;
721         __u32 padding;                            721         __u32 padding;
722   };                                              722   };
723                                                   723 
724   /* for KVM_SET_CPUID */                         724   /* for KVM_SET_CPUID */
725   struct kvm_cpuid {                              725   struct kvm_cpuid {
726         __u32 nent;                               726         __u32 nent;
727         __u32 padding;                            727         __u32 padding;
728         struct kvm_cpuid_entry entries[0];        728         struct kvm_cpuid_entry entries[0];
729   };                                              729   };
730                                                   730 
731                                                   731 
732 4.21 KVM_SET_SIGNAL_MASK                          732 4.21 KVM_SET_SIGNAL_MASK
733 ------------------------                          733 ------------------------
734                                                   734 
735 :Capability: basic                                735 :Capability: basic
736 :Architectures: all                               736 :Architectures: all
737 :Type: vcpu ioctl                                 737 :Type: vcpu ioctl
738 :Parameters: struct kvm_signal_mask (in)          738 :Parameters: struct kvm_signal_mask (in)
739 :Returns: 0 on success, -1 on error               739 :Returns: 0 on success, -1 on error
740                                                   740 
741 Defines which signals are blocked during execu    741 Defines which signals are blocked during execution of KVM_RUN.  This
742 signal mask temporarily overrides the threads     742 signal mask temporarily overrides the threads signal mask.  Any
743 unblocked signal received (except SIGKILL and     743 unblocked signal received (except SIGKILL and SIGSTOP, which retain
744 their traditional behaviour) will cause KVM_RU    744 their traditional behaviour) will cause KVM_RUN to return with -EINTR.
745                                                   745 
746 Note the signal will only be delivered if not     746 Note the signal will only be delivered if not blocked by the original
747 signal mask.                                      747 signal mask.
748                                                   748 
749 ::                                                749 ::
750                                                   750 
751   /* for KVM_SET_SIGNAL_MASK */                   751   /* for KVM_SET_SIGNAL_MASK */
752   struct kvm_signal_mask {                        752   struct kvm_signal_mask {
753         __u32 len;                                753         __u32 len;
754         __u8  sigset[0];                          754         __u8  sigset[0];
755   };                                              755   };
756                                                   756 
757                                                   757 
758 4.22 KVM_GET_FPU                                  758 4.22 KVM_GET_FPU
759 ----------------                                  759 ----------------
760                                                   760 
761 :Capability: basic                                761 :Capability: basic
762 :Architectures: x86, loongarch                    762 :Architectures: x86, loongarch
763 :Type: vcpu ioctl                                 763 :Type: vcpu ioctl
764 :Parameters: struct kvm_fpu (out)                 764 :Parameters: struct kvm_fpu (out)
765 :Returns: 0 on success, -1 on error               765 :Returns: 0 on success, -1 on error
766                                                   766 
767 Reads the floating point state from the vcpu.     767 Reads the floating point state from the vcpu.
768                                                   768 
769 ::                                                769 ::
770                                                   770 
771   /* x86: for KVM_GET_FPU and KVM_SET_FPU */      771   /* x86: for KVM_GET_FPU and KVM_SET_FPU */
772   struct kvm_fpu {                                772   struct kvm_fpu {
773         __u8  fpr[8][16];                         773         __u8  fpr[8][16];
774         __u16 fcw;                                774         __u16 fcw;
775         __u16 fsw;                                775         __u16 fsw;
776         __u8  ftwx;  /* in fxsave format */       776         __u8  ftwx;  /* in fxsave format */
777         __u8  pad1;                               777         __u8  pad1;
778         __u16 last_opcode;                        778         __u16 last_opcode;
779         __u64 last_ip;                            779         __u64 last_ip;
780         __u64 last_dp;                            780         __u64 last_dp;
781         __u8  xmm[16][16];                        781         __u8  xmm[16][16];
782         __u32 mxcsr;                              782         __u32 mxcsr;
783         __u32 pad2;                               783         __u32 pad2;
784   };                                              784   };
785                                                   785 
786   /* LoongArch: for KVM_GET_FPU and KVM_SET_FP    786   /* LoongArch: for KVM_GET_FPU and KVM_SET_FPU */
787   struct kvm_fpu {                                787   struct kvm_fpu {
788         __u32 fcsr;                               788         __u32 fcsr;
789         __u64 fcc;                                789         __u64 fcc;
790         struct kvm_fpureg {                       790         struct kvm_fpureg {
791                 __u64 val64[4];                   791                 __u64 val64[4];
792         }fpr[32];                                 792         }fpr[32];
793   };                                              793   };
794                                                   794 
795                                                   795 
796 4.23 KVM_SET_FPU                                  796 4.23 KVM_SET_FPU
797 ----------------                                  797 ----------------
798                                                   798 
799 :Capability: basic                                799 :Capability: basic
800 :Architectures: x86, loongarch                    800 :Architectures: x86, loongarch
801 :Type: vcpu ioctl                                 801 :Type: vcpu ioctl
802 :Parameters: struct kvm_fpu (in)                  802 :Parameters: struct kvm_fpu (in)
803 :Returns: 0 on success, -1 on error               803 :Returns: 0 on success, -1 on error
804                                                   804 
805 Writes the floating point state to the vcpu.      805 Writes the floating point state to the vcpu.
806                                                   806 
807 ::                                                807 ::
808                                                   808 
809   /* x86: for KVM_GET_FPU and KVM_SET_FPU */      809   /* x86: for KVM_GET_FPU and KVM_SET_FPU */
810   struct kvm_fpu {                                810   struct kvm_fpu {
811         __u8  fpr[8][16];                         811         __u8  fpr[8][16];
812         __u16 fcw;                                812         __u16 fcw;
813         __u16 fsw;                                813         __u16 fsw;
814         __u8  ftwx;  /* in fxsave format */       814         __u8  ftwx;  /* in fxsave format */
815         __u8  pad1;                               815         __u8  pad1;
816         __u16 last_opcode;                        816         __u16 last_opcode;
817         __u64 last_ip;                            817         __u64 last_ip;
818         __u64 last_dp;                            818         __u64 last_dp;
819         __u8  xmm[16][16];                        819         __u8  xmm[16][16];
820         __u32 mxcsr;                              820         __u32 mxcsr;
821         __u32 pad2;                               821         __u32 pad2;
822   };                                              822   };
823                                                   823 
824   /* LoongArch: for KVM_GET_FPU and KVM_SET_FP    824   /* LoongArch: for KVM_GET_FPU and KVM_SET_FPU */
825   struct kvm_fpu {                                825   struct kvm_fpu {
826         __u32 fcsr;                               826         __u32 fcsr;
827         __u64 fcc;                                827         __u64 fcc;
828         struct kvm_fpureg {                       828         struct kvm_fpureg {
829                 __u64 val64[4];                   829                 __u64 val64[4];
830         }fpr[32];                                 830         }fpr[32];
831   };                                              831   };
832                                                   832 
833                                                   833 
834 4.24 KVM_CREATE_IRQCHIP                           834 4.24 KVM_CREATE_IRQCHIP
835 -----------------------                           835 -----------------------
836                                                   836 
837 :Capability: KVM_CAP_IRQCHIP, KVM_CAP_S390_IRQ    837 :Capability: KVM_CAP_IRQCHIP, KVM_CAP_S390_IRQCHIP (s390)
838 :Architectures: x86, arm64, s390                  838 :Architectures: x86, arm64, s390
839 :Type: vm ioctl                                   839 :Type: vm ioctl
840 :Parameters: none                                 840 :Parameters: none
841 :Returns: 0 on success, -1 on error               841 :Returns: 0 on success, -1 on error
842                                                   842 
843 Creates an interrupt controller model in the k    843 Creates an interrupt controller model in the kernel.
844 On x86, creates a virtual ioapic, a virtual PI    844 On x86, creates a virtual ioapic, a virtual PIC (two PICs, nested), and sets up
845 future vcpus to have a local APIC.  IRQ routin    845 future vcpus to have a local APIC.  IRQ routing for GSIs 0-15 is set to both
846 PIC and IOAPIC; GSI 16-23 only go to the IOAPI    846 PIC and IOAPIC; GSI 16-23 only go to the IOAPIC.
847 On arm64, a GICv2 is created. Any other GIC ve    847 On arm64, a GICv2 is created. Any other GIC versions require the usage of
848 KVM_CREATE_DEVICE, which also supports creatin    848 KVM_CREATE_DEVICE, which also supports creating a GICv2.  Using
849 KVM_CREATE_DEVICE is preferred over KVM_CREATE    849 KVM_CREATE_DEVICE is preferred over KVM_CREATE_IRQCHIP for GICv2.
850 On s390, a dummy irq routing table is created.    850 On s390, a dummy irq routing table is created.
851                                                   851 
852 Note that on s390 the KVM_CAP_S390_IRQCHIP vm     852 Note that on s390 the KVM_CAP_S390_IRQCHIP vm capability needs to be enabled
853 before KVM_CREATE_IRQCHIP can be used.            853 before KVM_CREATE_IRQCHIP can be used.
854                                                   854 
855                                                   855 
856 4.25 KVM_IRQ_LINE                                 856 4.25 KVM_IRQ_LINE
857 -----------------                                 857 -----------------
858                                                   858 
859 :Capability: KVM_CAP_IRQCHIP                      859 :Capability: KVM_CAP_IRQCHIP
860 :Architectures: x86, arm64                        860 :Architectures: x86, arm64
861 :Type: vm ioctl                                   861 :Type: vm ioctl
862 :Parameters: struct kvm_irq_level                 862 :Parameters: struct kvm_irq_level
863 :Returns: 0 on success, -1 on error               863 :Returns: 0 on success, -1 on error
864                                                   864 
865 Sets the level of a GSI input to the interrupt    865 Sets the level of a GSI input to the interrupt controller model in the kernel.
866 On some architectures it is required that an i    866 On some architectures it is required that an interrupt controller model has
867 been previously created with KVM_CREATE_IRQCHI    867 been previously created with KVM_CREATE_IRQCHIP.  Note that edge-triggered
868 interrupts require the level to be set to 1 an    868 interrupts require the level to be set to 1 and then back to 0.
869                                                   869 
870 On real hardware, interrupt pins can be active    870 On real hardware, interrupt pins can be active-low or active-high.  This
871 does not matter for the level field of struct     871 does not matter for the level field of struct kvm_irq_level: 1 always
872 means active (asserted), 0 means inactive (dea    872 means active (asserted), 0 means inactive (deasserted).
873                                                   873 
874 x86 allows the operating system to program the    874 x86 allows the operating system to program the interrupt polarity
875 (active-low/active-high) for level-triggered i    875 (active-low/active-high) for level-triggered interrupts, and KVM used
876 to consider the polarity.  However, due to bit    876 to consider the polarity.  However, due to bitrot in the handling of
877 active-low interrupts, the above convention is    877 active-low interrupts, the above convention is now valid on x86 too.
878 This is signaled by KVM_CAP_X86_IOAPIC_POLARIT    878 This is signaled by KVM_CAP_X86_IOAPIC_POLARITY_IGNORED.  Userspace
879 should not present interrupts to the guest as     879 should not present interrupts to the guest as active-low unless this
880 capability is present (or unless it is not usi    880 capability is present (or unless it is not using the in-kernel irqchip,
881 of course).                                       881 of course).
882                                                   882 
883                                                   883 
884 arm64 can signal an interrupt either at the CP    884 arm64 can signal an interrupt either at the CPU level, or at the
885 in-kernel irqchip (GIC), and for in-kernel irq    885 in-kernel irqchip (GIC), and for in-kernel irqchip can tell the GIC to
886 use PPIs designated for specific cpus.  The ir    886 use PPIs designated for specific cpus.  The irq field is interpreted
887 like this::                                       887 like this::
888                                                   888 
889   bits:  |  31 ... 28  | 27 ... 24 | 23  ... 1    889   bits:  |  31 ... 28  | 27 ... 24 | 23  ... 16 | 15 ... 0 |
890   field: | vcpu2_index | irq_type  | vcpu_inde    890   field: | vcpu2_index | irq_type  | vcpu_index |  irq_id  |
891                                                   891 
892 The irq_type field has the following values:      892 The irq_type field has the following values:
893                                                   893 
894 - KVM_ARM_IRQ_TYPE_CPU:                           894 - KVM_ARM_IRQ_TYPE_CPU:
895                out-of-kernel GIC: irq_id 0 is     895                out-of-kernel GIC: irq_id 0 is IRQ, irq_id 1 is FIQ
896 - KVM_ARM_IRQ_TYPE_SPI:                           896 - KVM_ARM_IRQ_TYPE_SPI:
897                in-kernel GIC: SPI, irq_id betw    897                in-kernel GIC: SPI, irq_id between 32 and 1019 (incl.)
898                (the vcpu_index field is ignore    898                (the vcpu_index field is ignored)
899 - KVM_ARM_IRQ_TYPE_PPI:                           899 - KVM_ARM_IRQ_TYPE_PPI:
900                in-kernel GIC: PPI, irq_id betw    900                in-kernel GIC: PPI, irq_id between 16 and 31 (incl.)
901                                                   901 
902 (The irq_id field thus corresponds nicely to t    902 (The irq_id field thus corresponds nicely to the IRQ ID in the ARM GIC specs)
903                                                   903 
904 In both cases, level is used to assert/deasser    904 In both cases, level is used to assert/deassert the line.
905                                                   905 
906 When KVM_CAP_ARM_IRQ_LINE_LAYOUT_2 is supporte    906 When KVM_CAP_ARM_IRQ_LINE_LAYOUT_2 is supported, the target vcpu is
907 identified as (256 * vcpu2_index + vcpu_index)    907 identified as (256 * vcpu2_index + vcpu_index). Otherwise, vcpu2_index
908 must be zero.                                     908 must be zero.
909                                                   909 
910 Note that on arm64, the KVM_CAP_IRQCHIP capabi    910 Note that on arm64, the KVM_CAP_IRQCHIP capability only conditions
911 injection of interrupts for the in-kernel irqc    911 injection of interrupts for the in-kernel irqchip. KVM_IRQ_LINE can always
912 be used for a userspace interrupt controller.     912 be used for a userspace interrupt controller.
913                                                   913 
914 ::                                                914 ::
915                                                   915 
916   struct kvm_irq_level {                          916   struct kvm_irq_level {
917         union {                                   917         union {
918                 __u32 irq;     /* GSI */          918                 __u32 irq;     /* GSI */
919                 __s32 status;  /* not used for    919                 __s32 status;  /* not used for KVM_IRQ_LEVEL */
920         };                                        920         };
921         __u32 level;           /* 0 or 1 */       921         __u32 level;           /* 0 or 1 */
922   };                                              922   };
923                                                   923 
924                                                   924 
925 4.26 KVM_GET_IRQCHIP                              925 4.26 KVM_GET_IRQCHIP
926 --------------------                              926 --------------------
927                                                   927 
928 :Capability: KVM_CAP_IRQCHIP                      928 :Capability: KVM_CAP_IRQCHIP
929 :Architectures: x86                               929 :Architectures: x86
930 :Type: vm ioctl                                   930 :Type: vm ioctl
931 :Parameters: struct kvm_irqchip (in/out)          931 :Parameters: struct kvm_irqchip (in/out)
932 :Returns: 0 on success, -1 on error               932 :Returns: 0 on success, -1 on error
933                                                   933 
934 Reads the state of a kernel interrupt controll    934 Reads the state of a kernel interrupt controller created with
935 KVM_CREATE_IRQCHIP into a buffer provided by t    935 KVM_CREATE_IRQCHIP into a buffer provided by the caller.
936                                                   936 
937 ::                                                937 ::
938                                                   938 
939   struct kvm_irqchip {                            939   struct kvm_irqchip {
940         __u32 chip_id;  /* 0 = PIC1, 1 = PIC2,    940         __u32 chip_id;  /* 0 = PIC1, 1 = PIC2, 2 = IOAPIC */
941         __u32 pad;                                941         __u32 pad;
942         union {                                   942         union {
943                 char dummy[512];  /* reserving    943                 char dummy[512];  /* reserving space */
944                 struct kvm_pic_state pic;         944                 struct kvm_pic_state pic;
945                 struct kvm_ioapic_state ioapic    945                 struct kvm_ioapic_state ioapic;
946         } chip;                                   946         } chip;
947   };                                              947   };
948                                                   948 
949                                                   949 
950 4.27 KVM_SET_IRQCHIP                              950 4.27 KVM_SET_IRQCHIP
951 --------------------                              951 --------------------
952                                                   952 
953 :Capability: KVM_CAP_IRQCHIP                      953 :Capability: KVM_CAP_IRQCHIP
954 :Architectures: x86                               954 :Architectures: x86
955 :Type: vm ioctl                                   955 :Type: vm ioctl
956 :Parameters: struct kvm_irqchip (in)              956 :Parameters: struct kvm_irqchip (in)
957 :Returns: 0 on success, -1 on error               957 :Returns: 0 on success, -1 on error
958                                                   958 
959 Sets the state of a kernel interrupt controlle    959 Sets the state of a kernel interrupt controller created with
960 KVM_CREATE_IRQCHIP from a buffer provided by t    960 KVM_CREATE_IRQCHIP from a buffer provided by the caller.
961                                                   961 
962 ::                                                962 ::
963                                                   963 
964   struct kvm_irqchip {                            964   struct kvm_irqchip {
965         __u32 chip_id;  /* 0 = PIC1, 1 = PIC2,    965         __u32 chip_id;  /* 0 = PIC1, 1 = PIC2, 2 = IOAPIC */
966         __u32 pad;                                966         __u32 pad;
967         union {                                   967         union {
968                 char dummy[512];  /* reserving    968                 char dummy[512];  /* reserving space */
969                 struct kvm_pic_state pic;         969                 struct kvm_pic_state pic;
970                 struct kvm_ioapic_state ioapic    970                 struct kvm_ioapic_state ioapic;
971         } chip;                                   971         } chip;
972   };                                              972   };
973                                                   973 
974                                                   974 
975 4.28 KVM_XEN_HVM_CONFIG                           975 4.28 KVM_XEN_HVM_CONFIG
976 -----------------------                           976 -----------------------
977                                                   977 
978 :Capability: KVM_CAP_XEN_HVM                      978 :Capability: KVM_CAP_XEN_HVM
979 :Architectures: x86                               979 :Architectures: x86
980 :Type: vm ioctl                                   980 :Type: vm ioctl
981 :Parameters: struct kvm_xen_hvm_config (in)       981 :Parameters: struct kvm_xen_hvm_config (in)
982 :Returns: 0 on success, -1 on error               982 :Returns: 0 on success, -1 on error
983                                                   983 
984 Sets the MSR that the Xen HVM guest uses to in    984 Sets the MSR that the Xen HVM guest uses to initialize its hypercall
985 page, and provides the starting address and si    985 page, and provides the starting address and size of the hypercall
986 blobs in userspace.  When the guest writes the    986 blobs in userspace.  When the guest writes the MSR, kvm copies one
987 page of a blob (32- or 64-bit, depending on th    987 page of a blob (32- or 64-bit, depending on the vcpu mode) to guest
988 memory.                                           988 memory.
989                                                   989 
990 ::                                                990 ::
991                                                   991 
992   struct kvm_xen_hvm_config {                     992   struct kvm_xen_hvm_config {
993         __u32 flags;                              993         __u32 flags;
994         __u32 msr;                                994         __u32 msr;
995         __u64 blob_addr_32;                       995         __u64 blob_addr_32;
996         __u64 blob_addr_64;                       996         __u64 blob_addr_64;
997         __u8 blob_size_32;                        997         __u8 blob_size_32;
998         __u8 blob_size_64;                        998         __u8 blob_size_64;
999         __u8 pad2[30];                            999         __u8 pad2[30];
1000   };                                             1000   };
1001                                                  1001 
1002 If certain flags are returned from the KVM_CA    1002 If certain flags are returned from the KVM_CAP_XEN_HVM check, they may
1003 be set in the flags field of this ioctl:         1003 be set in the flags field of this ioctl:
1004                                                  1004 
1005 The KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL flag r    1005 The KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL flag requests KVM to generate
1006 the contents of the hypercall page automatica    1006 the contents of the hypercall page automatically; hypercalls will be
1007 intercepted and passed to userspace through K    1007 intercepted and passed to userspace through KVM_EXIT_XEN.  In this
1008 case, all of the blob size and address fields    1008 case, all of the blob size and address fields must be zero.
1009                                                  1009 
1010 The KVM_XEN_HVM_CONFIG_EVTCHN_SEND flag indic    1010 The KVM_XEN_HVM_CONFIG_EVTCHN_SEND flag indicates to KVM that userspace
1011 will always use the KVM_XEN_HVM_EVTCHN_SEND i    1011 will always use the KVM_XEN_HVM_EVTCHN_SEND ioctl to deliver event
1012 channel interrupts rather than manipulating t    1012 channel interrupts rather than manipulating the guest's shared_info
1013 structures directly. This, in turn, may allow    1013 structures directly. This, in turn, may allow KVM to enable features
1014 such as intercepting the SCHEDOP_poll hyperca    1014 such as intercepting the SCHEDOP_poll hypercall to accelerate PV
1015 spinlock operation for the guest. Userspace m    1015 spinlock operation for the guest. Userspace may still use the ioctl
1016 to deliver events if it was advertised, even     1016 to deliver events if it was advertised, even if userspace does not
1017 send this indication that it will always do s    1017 send this indication that it will always do so
1018                                                  1018 
1019 No other flags are currently valid in the str    1019 No other flags are currently valid in the struct kvm_xen_hvm_config.
1020                                                  1020 
1021 4.29 KVM_GET_CLOCK                               1021 4.29 KVM_GET_CLOCK
1022 ------------------                               1022 ------------------
1023                                                  1023 
1024 :Capability: KVM_CAP_ADJUST_CLOCK                1024 :Capability: KVM_CAP_ADJUST_CLOCK
1025 :Architectures: x86                              1025 :Architectures: x86
1026 :Type: vm ioctl                                  1026 :Type: vm ioctl
1027 :Parameters: struct kvm_clock_data (out)         1027 :Parameters: struct kvm_clock_data (out)
1028 :Returns: 0 on success, -1 on error              1028 :Returns: 0 on success, -1 on error
1029                                                  1029 
1030 Gets the current timestamp of kvmclock as see    1030 Gets the current timestamp of kvmclock as seen by the current guest. In
1031 conjunction with KVM_SET_CLOCK, it is used to    1031 conjunction with KVM_SET_CLOCK, it is used to ensure monotonicity on scenarios
1032 such as migration.                               1032 such as migration.
1033                                                  1033 
1034 When KVM_CAP_ADJUST_CLOCK is passed to KVM_CH    1034 When KVM_CAP_ADJUST_CLOCK is passed to KVM_CHECK_EXTENSION, it returns the
1035 set of bits that KVM can return in struct kvm    1035 set of bits that KVM can return in struct kvm_clock_data's flag member.
1036                                                  1036 
1037 The following flags are defined:                 1037 The following flags are defined:
1038                                                  1038 
1039 KVM_CLOCK_TSC_STABLE                             1039 KVM_CLOCK_TSC_STABLE
1040   If set, the returned value is the exact kvm    1040   If set, the returned value is the exact kvmclock
1041   value seen by all VCPUs at the instant when    1041   value seen by all VCPUs at the instant when KVM_GET_CLOCK was called.
1042   If clear, the returned value is simply CLOC    1042   If clear, the returned value is simply CLOCK_MONOTONIC plus a constant
1043   offset; the offset can be modified with KVM    1043   offset; the offset can be modified with KVM_SET_CLOCK.  KVM will try
1044   to make all VCPUs follow this clock, but th    1044   to make all VCPUs follow this clock, but the exact value read by each
1045   VCPU could differ, because the host TSC is     1045   VCPU could differ, because the host TSC is not stable.
1046                                                  1046 
1047 KVM_CLOCK_REALTIME                               1047 KVM_CLOCK_REALTIME
1048   If set, the `realtime` field in the kvm_clo    1048   If set, the `realtime` field in the kvm_clock_data
1049   structure is populated with the value of th    1049   structure is populated with the value of the host's real time
1050   clocksource at the instant when KVM_GET_CLO    1050   clocksource at the instant when KVM_GET_CLOCK was called. If clear,
1051   the `realtime` field does not contain a val    1051   the `realtime` field does not contain a value.
1052                                                  1052 
1053 KVM_CLOCK_HOST_TSC                               1053 KVM_CLOCK_HOST_TSC
1054   If set, the `host_tsc` field in the kvm_clo    1054   If set, the `host_tsc` field in the kvm_clock_data
1055   structure is populated with the value of th    1055   structure is populated with the value of the host's timestamp counter (TSC)
1056   at the instant when KVM_GET_CLOCK was calle    1056   at the instant when KVM_GET_CLOCK was called. If clear, the `host_tsc` field
1057   does not contain a value.                      1057   does not contain a value.
1058                                                  1058 
1059 ::                                               1059 ::
1060                                                  1060 
1061   struct kvm_clock_data {                        1061   struct kvm_clock_data {
1062         __u64 clock;  /* kvmclock current val    1062         __u64 clock;  /* kvmclock current value */
1063         __u32 flags;                             1063         __u32 flags;
1064         __u32 pad0;                              1064         __u32 pad0;
1065         __u64 realtime;                          1065         __u64 realtime;
1066         __u64 host_tsc;                          1066         __u64 host_tsc;
1067         __u32 pad[4];                            1067         __u32 pad[4];
1068   };                                             1068   };
1069                                                  1069 
1070                                                  1070 
1071 4.30 KVM_SET_CLOCK                               1071 4.30 KVM_SET_CLOCK
1072 ------------------                               1072 ------------------
1073                                                  1073 
1074 :Capability: KVM_CAP_ADJUST_CLOCK                1074 :Capability: KVM_CAP_ADJUST_CLOCK
1075 :Architectures: x86                              1075 :Architectures: x86
1076 :Type: vm ioctl                                  1076 :Type: vm ioctl
1077 :Parameters: struct kvm_clock_data (in)          1077 :Parameters: struct kvm_clock_data (in)
1078 :Returns: 0 on success, -1 on error              1078 :Returns: 0 on success, -1 on error
1079                                                  1079 
1080 Sets the current timestamp of kvmclock to the    1080 Sets the current timestamp of kvmclock to the value specified in its parameter.
1081 In conjunction with KVM_GET_CLOCK, it is used    1081 In conjunction with KVM_GET_CLOCK, it is used to ensure monotonicity on scenarios
1082 such as migration.                               1082 such as migration.
1083                                                  1083 
1084 The following flags can be passed:               1084 The following flags can be passed:
1085                                                  1085 
1086 KVM_CLOCK_REALTIME                               1086 KVM_CLOCK_REALTIME
1087   If set, KVM will compare the value of the `    1087   If set, KVM will compare the value of the `realtime` field
1088   with the value of the host's real time cloc    1088   with the value of the host's real time clocksource at the instant when
1089   KVM_SET_CLOCK was called. The difference in    1089   KVM_SET_CLOCK was called. The difference in elapsed time is added to the final
1090   kvmclock value that will be provided to gue    1090   kvmclock value that will be provided to guests.
1091                                                  1091 
1092 Other flags returned by ``KVM_GET_CLOCK`` are    1092 Other flags returned by ``KVM_GET_CLOCK`` are accepted but ignored.
1093                                                  1093 
1094 ::                                               1094 ::
1095                                                  1095 
1096   struct kvm_clock_data {                        1096   struct kvm_clock_data {
1097         __u64 clock;  /* kvmclock current val    1097         __u64 clock;  /* kvmclock current value */
1098         __u32 flags;                             1098         __u32 flags;
1099         __u32 pad0;                              1099         __u32 pad0;
1100         __u64 realtime;                          1100         __u64 realtime;
1101         __u64 host_tsc;                          1101         __u64 host_tsc;
1102         __u32 pad[4];                            1102         __u32 pad[4];
1103   };                                             1103   };
1104                                                  1104 
1105                                                  1105 
1106 4.31 KVM_GET_VCPU_EVENTS                         1106 4.31 KVM_GET_VCPU_EVENTS
1107 ------------------------                         1107 ------------------------
1108                                                  1108 
1109 :Capability: KVM_CAP_VCPU_EVENTS                 1109 :Capability: KVM_CAP_VCPU_EVENTS
1110 :Extended by: KVM_CAP_INTR_SHADOW                1110 :Extended by: KVM_CAP_INTR_SHADOW
1111 :Architectures: x86, arm64                       1111 :Architectures: x86, arm64
1112 :Type: vcpu ioctl                                1112 :Type: vcpu ioctl
1113 :Parameters: struct kvm_vcpu_events (out)        1113 :Parameters: struct kvm_vcpu_events (out)
1114 :Returns: 0 on success, -1 on error              1114 :Returns: 0 on success, -1 on error
1115                                                  1115 
1116 X86:                                             1116 X86:
1117 ^^^^                                             1117 ^^^^
1118                                                  1118 
1119 Gets currently pending exceptions, interrupts    1119 Gets currently pending exceptions, interrupts, and NMIs as well as related
1120 states of the vcpu.                              1120 states of the vcpu.
1121                                                  1121 
1122 ::                                               1122 ::
1123                                                  1123 
1124   struct kvm_vcpu_events {                       1124   struct kvm_vcpu_events {
1125         struct {                                 1125         struct {
1126                 __u8 injected;                   1126                 __u8 injected;
1127                 __u8 nr;                         1127                 __u8 nr;
1128                 __u8 has_error_code;             1128                 __u8 has_error_code;
1129                 __u8 pending;                    1129                 __u8 pending;
1130                 __u32 error_code;                1130                 __u32 error_code;
1131         } exception;                             1131         } exception;
1132         struct {                                 1132         struct {
1133                 __u8 injected;                   1133                 __u8 injected;
1134                 __u8 nr;                         1134                 __u8 nr;
1135                 __u8 soft;                       1135                 __u8 soft;
1136                 __u8 shadow;                     1136                 __u8 shadow;
1137         } interrupt;                             1137         } interrupt;
1138         struct {                                 1138         struct {
1139                 __u8 injected;                   1139                 __u8 injected;
1140                 __u8 pending;                    1140                 __u8 pending;
1141                 __u8 masked;                     1141                 __u8 masked;
1142                 __u8 pad;                        1142                 __u8 pad;
1143         } nmi;                                   1143         } nmi;
1144         __u32 sipi_vector;                       1144         __u32 sipi_vector;
1145         __u32 flags;                             1145         __u32 flags;
1146         struct {                                 1146         struct {
1147                 __u8 smm;                        1147                 __u8 smm;
1148                 __u8 pending;                    1148                 __u8 pending;
1149                 __u8 smm_inside_nmi;             1149                 __u8 smm_inside_nmi;
1150                 __u8 latched_init;               1150                 __u8 latched_init;
1151         } smi;                                   1151         } smi;
1152         __u8 reserved[27];                       1152         __u8 reserved[27];
1153         __u8 exception_has_payload;              1153         __u8 exception_has_payload;
1154         __u64 exception_payload;                 1154         __u64 exception_payload;
1155   };                                             1155   };
1156                                                  1156 
1157 The following bits are defined in the flags f    1157 The following bits are defined in the flags field:
1158                                                  1158 
1159 - KVM_VCPUEVENT_VALID_SHADOW may be set to si    1159 - KVM_VCPUEVENT_VALID_SHADOW may be set to signal that
1160   interrupt.shadow contains a valid state.       1160   interrupt.shadow contains a valid state.
1161                                                  1161 
1162 - KVM_VCPUEVENT_VALID_SMM may be set to signa    1162 - KVM_VCPUEVENT_VALID_SMM may be set to signal that smi contains a
1163   valid state.                                   1163   valid state.
1164                                                  1164 
1165 - KVM_VCPUEVENT_VALID_PAYLOAD may be set to s    1165 - KVM_VCPUEVENT_VALID_PAYLOAD may be set to signal that the
1166   exception_has_payload, exception_payload, a    1166   exception_has_payload, exception_payload, and exception.pending
1167   fields contain a valid state. This bit will    1167   fields contain a valid state. This bit will be set whenever
1168   KVM_CAP_EXCEPTION_PAYLOAD is enabled.          1168   KVM_CAP_EXCEPTION_PAYLOAD is enabled.
1169                                                  1169 
1170 - KVM_VCPUEVENT_VALID_TRIPLE_FAULT may be set    1170 - KVM_VCPUEVENT_VALID_TRIPLE_FAULT may be set to signal that the
1171   triple_fault_pending field contains a valid    1171   triple_fault_pending field contains a valid state. This bit will
1172   be set whenever KVM_CAP_X86_TRIPLE_FAULT_EV    1172   be set whenever KVM_CAP_X86_TRIPLE_FAULT_EVENT is enabled.
1173                                                  1173 
1174 ARM64:                                           1174 ARM64:
1175 ^^^^^^                                           1175 ^^^^^^
1176                                                  1176 
1177 If the guest accesses a device that is being     1177 If the guest accesses a device that is being emulated by the host kernel in
1178 such a way that a real device would generate     1178 such a way that a real device would generate a physical SError, KVM may make
1179 a virtual SError pending for that VCPU. This     1179 a virtual SError pending for that VCPU. This system error interrupt remains
1180 pending until the guest takes the exception b    1180 pending until the guest takes the exception by unmasking PSTATE.A.
1181                                                  1181 
1182 Running the VCPU may cause it to take a pendi    1182 Running the VCPU may cause it to take a pending SError, or make an access that
1183 causes an SError to become pending. The event    1183 causes an SError to become pending. The event's description is only valid while
1184 the VPCU is not running.                         1184 the VPCU is not running.
1185                                                  1185 
1186 This API provides a way to read and write the    1186 This API provides a way to read and write the pending 'event' state that is not
1187 visible to the guest. To save, restore or mig    1187 visible to the guest. To save, restore or migrate a VCPU the struct representing
1188 the state can be read then written using this    1188 the state can be read then written using this GET/SET API, along with the other
1189 guest-visible registers. It is not possible t    1189 guest-visible registers. It is not possible to 'cancel' an SError that has been
1190 made pending.                                    1190 made pending.
1191                                                  1191 
1192 A device being emulated in user-space may als    1192 A device being emulated in user-space may also wish to generate an SError. To do
1193 this the events structure can be populated by    1193 this the events structure can be populated by user-space. The current state
1194 should be read first, to ensure no existing S    1194 should be read first, to ensure no existing SError is pending. If an existing
1195 SError is pending, the architecture's 'Multip    1195 SError is pending, the architecture's 'Multiple SError interrupts' rules should
1196 be followed. (2.5.3 of DDI0587.a "ARM Reliabi    1196 be followed. (2.5.3 of DDI0587.a "ARM Reliability, Availability, and
1197 Serviceability (RAS) Specification").            1197 Serviceability (RAS) Specification").
1198                                                  1198 
1199 SError exceptions always have an ESR value. S    1199 SError exceptions always have an ESR value. Some CPUs have the ability to
1200 specify what the virtual SError's ESR value s    1200 specify what the virtual SError's ESR value should be. These systems will
1201 advertise KVM_CAP_ARM_INJECT_SERROR_ESR. In t    1201 advertise KVM_CAP_ARM_INJECT_SERROR_ESR. In this case exception.has_esr will
1202 always have a non-zero value when read, and t    1202 always have a non-zero value when read, and the agent making an SError pending
1203 should specify the ISS field in the lower 24     1203 should specify the ISS field in the lower 24 bits of exception.serror_esr. If
1204 the system supports KVM_CAP_ARM_INJECT_SERROR    1204 the system supports KVM_CAP_ARM_INJECT_SERROR_ESR, but user-space sets the events
1205 with exception.has_esr as zero, KVM will choo    1205 with exception.has_esr as zero, KVM will choose an ESR.
1206                                                  1206 
1207 Specifying exception.has_esr on a system that    1207 Specifying exception.has_esr on a system that does not support it will return
1208 -EINVAL. Setting anything other than the lowe    1208 -EINVAL. Setting anything other than the lower 24bits of exception.serror_esr
1209 will return -EINVAL.                             1209 will return -EINVAL.
1210                                                  1210 
1211 It is not possible to read back a pending ext    1211 It is not possible to read back a pending external abort (injected via
1212 KVM_SET_VCPU_EVENTS or otherwise) because suc    1212 KVM_SET_VCPU_EVENTS or otherwise) because such an exception is always delivered
1213 directly to the virtual CPU).                    1213 directly to the virtual CPU).
1214                                                  1214 
1215 ::                                               1215 ::
1216                                                  1216 
1217   struct kvm_vcpu_events {                       1217   struct kvm_vcpu_events {
1218         struct {                                 1218         struct {
1219                 __u8 serror_pending;             1219                 __u8 serror_pending;
1220                 __u8 serror_has_esr;             1220                 __u8 serror_has_esr;
1221                 __u8 ext_dabt_pending;           1221                 __u8 ext_dabt_pending;
1222                 /* Align it to 8 bytes */        1222                 /* Align it to 8 bytes */
1223                 __u8 pad[5];                     1223                 __u8 pad[5];
1224                 __u64 serror_esr;                1224                 __u64 serror_esr;
1225         } exception;                             1225         } exception;
1226         __u32 reserved[12];                      1226         __u32 reserved[12];
1227   };                                             1227   };
1228                                                  1228 
1229 4.32 KVM_SET_VCPU_EVENTS                         1229 4.32 KVM_SET_VCPU_EVENTS
1230 ------------------------                         1230 ------------------------
1231                                                  1231 
1232 :Capability: KVM_CAP_VCPU_EVENTS                 1232 :Capability: KVM_CAP_VCPU_EVENTS
1233 :Extended by: KVM_CAP_INTR_SHADOW                1233 :Extended by: KVM_CAP_INTR_SHADOW
1234 :Architectures: x86, arm64                       1234 :Architectures: x86, arm64
1235 :Type: vcpu ioctl                                1235 :Type: vcpu ioctl
1236 :Parameters: struct kvm_vcpu_events (in)         1236 :Parameters: struct kvm_vcpu_events (in)
1237 :Returns: 0 on success, -1 on error              1237 :Returns: 0 on success, -1 on error
1238                                                  1238 
1239 X86:                                             1239 X86:
1240 ^^^^                                             1240 ^^^^
1241                                                  1241 
1242 Set pending exceptions, interrupts, and NMIs     1242 Set pending exceptions, interrupts, and NMIs as well as related states of the
1243 vcpu.                                            1243 vcpu.
1244                                                  1244 
1245 See KVM_GET_VCPU_EVENTS for the data structur    1245 See KVM_GET_VCPU_EVENTS for the data structure.
1246                                                  1246 
1247 Fields that may be modified asynchronously by    1247 Fields that may be modified asynchronously by running VCPUs can be excluded
1248 from the update. These fields are nmi.pending    1248 from the update. These fields are nmi.pending, sipi_vector, smi.smm,
1249 smi.pending. Keep the corresponding bits in t    1249 smi.pending. Keep the corresponding bits in the flags field cleared to
1250 suppress overwriting the current in-kernel st    1250 suppress overwriting the current in-kernel state. The bits are:
1251                                                  1251 
1252 ===============================  ============    1252 ===============================  ==================================
1253 KVM_VCPUEVENT_VALID_NMI_PENDING  transfer nmi    1253 KVM_VCPUEVENT_VALID_NMI_PENDING  transfer nmi.pending to the kernel
1254 KVM_VCPUEVENT_VALID_SIPI_VECTOR  transfer sip    1254 KVM_VCPUEVENT_VALID_SIPI_VECTOR  transfer sipi_vector
1255 KVM_VCPUEVENT_VALID_SMM          transfer the    1255 KVM_VCPUEVENT_VALID_SMM          transfer the smi sub-struct.
1256 ===============================  ============    1256 ===============================  ==================================
1257                                                  1257 
1258 If KVM_CAP_INTR_SHADOW is available, KVM_VCPU    1258 If KVM_CAP_INTR_SHADOW is available, KVM_VCPUEVENT_VALID_SHADOW can be set in
1259 the flags field to signal that interrupt.shad    1259 the flags field to signal that interrupt.shadow contains a valid state and
1260 shall be written into the VCPU.                  1260 shall be written into the VCPU.
1261                                                  1261 
1262 KVM_VCPUEVENT_VALID_SMM can only be set if KV    1262 KVM_VCPUEVENT_VALID_SMM can only be set if KVM_CAP_X86_SMM is available.
1263                                                  1263 
1264 If KVM_CAP_EXCEPTION_PAYLOAD is enabled, KVM_    1264 If KVM_CAP_EXCEPTION_PAYLOAD is enabled, KVM_VCPUEVENT_VALID_PAYLOAD
1265 can be set in the flags field to signal that     1265 can be set in the flags field to signal that the
1266 exception_has_payload, exception_payload, and    1266 exception_has_payload, exception_payload, and exception.pending fields
1267 contain a valid state and shall be written in    1267 contain a valid state and shall be written into the VCPU.
1268                                                  1268 
1269 If KVM_CAP_X86_TRIPLE_FAULT_EVENT is enabled,    1269 If KVM_CAP_X86_TRIPLE_FAULT_EVENT is enabled, KVM_VCPUEVENT_VALID_TRIPLE_FAULT
1270 can be set in flags field to signal that the     1270 can be set in flags field to signal that the triple_fault field contains
1271 a valid state and shall be written into the V    1271 a valid state and shall be written into the VCPU.
1272                                                  1272 
1273 ARM64:                                           1273 ARM64:
1274 ^^^^^^                                           1274 ^^^^^^
1275                                                  1275 
1276 User space may need to inject several types o    1276 User space may need to inject several types of events to the guest.
1277                                                  1277 
1278 Set the pending SError exception state for th    1278 Set the pending SError exception state for this VCPU. It is not possible to
1279 'cancel' an Serror that has been made pending    1279 'cancel' an Serror that has been made pending.
1280                                                  1280 
1281 If the guest performed an access to I/O memor    1281 If the guest performed an access to I/O memory which could not be handled by
1282 userspace, for example because of missing ins    1282 userspace, for example because of missing instruction syndrome decode
1283 information or because there is no device map    1283 information or because there is no device mapped at the accessed IPA, then
1284 userspace can ask the kernel to inject an ext    1284 userspace can ask the kernel to inject an external abort using the address
1285 from the exiting fault on the VCPU. It is a p    1285 from the exiting fault on the VCPU. It is a programming error to set
1286 ext_dabt_pending after an exit which was not     1286 ext_dabt_pending after an exit which was not either KVM_EXIT_MMIO or
1287 KVM_EXIT_ARM_NISV. This feature is only avail    1287 KVM_EXIT_ARM_NISV. This feature is only available if the system supports
1288 KVM_CAP_ARM_INJECT_EXT_DABT. This is a helper    1288 KVM_CAP_ARM_INJECT_EXT_DABT. This is a helper which provides commonality in
1289 how userspace reports accesses for the above     1289 how userspace reports accesses for the above cases to guests, across different
1290 userspace implementations. Nevertheless, user    1290 userspace implementations. Nevertheless, userspace can still emulate all Arm
1291 exceptions by manipulating individual registe    1291 exceptions by manipulating individual registers using the KVM_SET_ONE_REG API.
1292                                                  1292 
1293 See KVM_GET_VCPU_EVENTS for the data structur    1293 See KVM_GET_VCPU_EVENTS for the data structure.
1294                                                  1294 
1295                                                  1295 
1296 4.33 KVM_GET_DEBUGREGS                           1296 4.33 KVM_GET_DEBUGREGS
1297 ----------------------                           1297 ----------------------
1298                                                  1298 
1299 :Capability: KVM_CAP_DEBUGREGS                   1299 :Capability: KVM_CAP_DEBUGREGS
1300 :Architectures: x86                              1300 :Architectures: x86
1301 :Type: vm ioctl                                  1301 :Type: vm ioctl
1302 :Parameters: struct kvm_debugregs (out)          1302 :Parameters: struct kvm_debugregs (out)
1303 :Returns: 0 on success, -1 on error              1303 :Returns: 0 on success, -1 on error
1304                                                  1304 
1305 Reads debug registers from the vcpu.             1305 Reads debug registers from the vcpu.
1306                                                  1306 
1307 ::                                               1307 ::
1308                                                  1308 
1309   struct kvm_debugregs {                         1309   struct kvm_debugregs {
1310         __u64 db[4];                             1310         __u64 db[4];
1311         __u64 dr6;                               1311         __u64 dr6;
1312         __u64 dr7;                               1312         __u64 dr7;
1313         __u64 flags;                             1313         __u64 flags;
1314         __u64 reserved[9];                       1314         __u64 reserved[9];
1315   };                                             1315   };
1316                                                  1316 
1317                                                  1317 
1318 4.34 KVM_SET_DEBUGREGS                           1318 4.34 KVM_SET_DEBUGREGS
1319 ----------------------                           1319 ----------------------
1320                                                  1320 
1321 :Capability: KVM_CAP_DEBUGREGS                   1321 :Capability: KVM_CAP_DEBUGREGS
1322 :Architectures: x86                              1322 :Architectures: x86
1323 :Type: vm ioctl                                  1323 :Type: vm ioctl
1324 :Parameters: struct kvm_debugregs (in)           1324 :Parameters: struct kvm_debugregs (in)
1325 :Returns: 0 on success, -1 on error              1325 :Returns: 0 on success, -1 on error
1326                                                  1326 
1327 Writes debug registers into the vcpu.            1327 Writes debug registers into the vcpu.
1328                                                  1328 
1329 See KVM_GET_DEBUGREGS for the data structure.    1329 See KVM_GET_DEBUGREGS for the data structure. The flags field is unused
1330 yet and must be cleared on entry.                1330 yet and must be cleared on entry.
1331                                                  1331 
1332                                                  1332 
1333 4.35 KVM_SET_USER_MEMORY_REGION                  1333 4.35 KVM_SET_USER_MEMORY_REGION
1334 -------------------------------                  1334 -------------------------------
1335                                                  1335 
1336 :Capability: KVM_CAP_USER_MEMORY                 1336 :Capability: KVM_CAP_USER_MEMORY
1337 :Architectures: all                              1337 :Architectures: all
1338 :Type: vm ioctl                                  1338 :Type: vm ioctl
1339 :Parameters: struct kvm_userspace_memory_regi    1339 :Parameters: struct kvm_userspace_memory_region (in)
1340 :Returns: 0 on success, -1 on error              1340 :Returns: 0 on success, -1 on error
1341                                                  1341 
1342 ::                                               1342 ::
1343                                                  1343 
1344   struct kvm_userspace_memory_region {           1344   struct kvm_userspace_memory_region {
1345         __u32 slot;                              1345         __u32 slot;
1346         __u32 flags;                             1346         __u32 flags;
1347         __u64 guest_phys_addr;                   1347         __u64 guest_phys_addr;
1348         __u64 memory_size; /* bytes */           1348         __u64 memory_size; /* bytes */
1349         __u64 userspace_addr; /* start of the    1349         __u64 userspace_addr; /* start of the userspace allocated memory */
1350   };                                             1350   };
1351                                                  1351 
1352   /* for kvm_userspace_memory_region::flags *    1352   /* for kvm_userspace_memory_region::flags */
1353   #define KVM_MEM_LOG_DIRTY_PAGES       (1UL     1353   #define KVM_MEM_LOG_DIRTY_PAGES       (1UL << 0)
1354   #define KVM_MEM_READONLY      (1UL << 1)       1354   #define KVM_MEM_READONLY      (1UL << 1)
1355                                                  1355 
1356 This ioctl allows the user to create, modify     1356 This ioctl allows the user to create, modify or delete a guest physical
1357 memory slot.  Bits 0-15 of "slot" specify the    1357 memory slot.  Bits 0-15 of "slot" specify the slot id and this value
1358 should be less than the maximum number of use    1358 should be less than the maximum number of user memory slots supported per
1359 VM.  The maximum allowed slots can be queried    1359 VM.  The maximum allowed slots can be queried using KVM_CAP_NR_MEMSLOTS.
1360 Slots may not overlap in guest physical addre    1360 Slots may not overlap in guest physical address space.
1361                                                  1361 
1362 If KVM_CAP_MULTI_ADDRESS_SPACE is available,     1362 If KVM_CAP_MULTI_ADDRESS_SPACE is available, bits 16-31 of "slot"
1363 specifies the address space which is being mo    1363 specifies the address space which is being modified.  They must be
1364 less than the value that KVM_CHECK_EXTENSION     1364 less than the value that KVM_CHECK_EXTENSION returns for the
1365 KVM_CAP_MULTI_ADDRESS_SPACE capability.  Slot    1365 KVM_CAP_MULTI_ADDRESS_SPACE capability.  Slots in separate address spaces
1366 are unrelated; the restriction on overlapping    1366 are unrelated; the restriction on overlapping slots only applies within
1367 each address space.                              1367 each address space.
1368                                                  1368 
1369 Deleting a slot is done by passing zero for m    1369 Deleting a slot is done by passing zero for memory_size.  When changing
1370 an existing slot, it may be moved in the gues    1370 an existing slot, it may be moved in the guest physical memory space,
1371 or its flags may be modified, but it may not     1371 or its flags may be modified, but it may not be resized.
1372                                                  1372 
1373 Memory for the region is taken starting at th    1373 Memory for the region is taken starting at the address denoted by the
1374 field userspace_addr, which must point at use    1374 field userspace_addr, which must point at user addressable memory for
1375 the entire memory slot size.  Any object may     1375 the entire memory slot size.  Any object may back this memory, including
1376 anonymous memory, ordinary files, and hugetlb    1376 anonymous memory, ordinary files, and hugetlbfs.
1377                                                  1377 
1378 On architectures that support a form of addre    1378 On architectures that support a form of address tagging, userspace_addr must
1379 be an untagged address.                          1379 be an untagged address.
1380                                                  1380 
1381 It is recommended that the lower 21 bits of g    1381 It is recommended that the lower 21 bits of guest_phys_addr and userspace_addr
1382 be identical.  This allows large pages in the    1382 be identical.  This allows large pages in the guest to be backed by large
1383 pages in the host.                               1383 pages in the host.
1384                                                  1384 
1385 The flags field supports two flags: KVM_MEM_L    1385 The flags field supports two flags: KVM_MEM_LOG_DIRTY_PAGES and
1386 KVM_MEM_READONLY.  The former can be set to i    1386 KVM_MEM_READONLY.  The former can be set to instruct KVM to keep track of
1387 writes to memory within the slot.  See KVM_GE    1387 writes to memory within the slot.  See KVM_GET_DIRTY_LOG ioctl to know how to
1388 use it.  The latter can be set, if KVM_CAP_RE    1388 use it.  The latter can be set, if KVM_CAP_READONLY_MEM capability allows it,
1389 to make a new slot read-only.  In this case,     1389 to make a new slot read-only.  In this case, writes to this memory will be
1390 posted to userspace as KVM_EXIT_MMIO exits.      1390 posted to userspace as KVM_EXIT_MMIO exits.
1391                                                  1391 
1392 When the KVM_CAP_SYNC_MMU capability is avail    1392 When the KVM_CAP_SYNC_MMU capability is available, changes in the backing of
1393 the memory region are automatically reflected    1393 the memory region are automatically reflected into the guest.  For example, an
1394 mmap() that affects the region will be made v    1394 mmap() that affects the region will be made visible immediately.  Another
1395 example is madvise(MADV_DROP).                   1395 example is madvise(MADV_DROP).
1396                                                  1396 
1397 Note: On arm64, a write generated by the page    1397 Note: On arm64, a write generated by the page-table walker (to update
1398 the Access and Dirty flags, for example) neve    1398 the Access and Dirty flags, for example) never results in a
1399 KVM_EXIT_MMIO exit when the slot has the KVM_    1399 KVM_EXIT_MMIO exit when the slot has the KVM_MEM_READONLY flag. This
1400 is because KVM cannot provide the data that w    1400 is because KVM cannot provide the data that would be written by the
1401 page-table walker, making it impossible to em    1401 page-table walker, making it impossible to emulate the access.
1402 Instead, an abort (data abort if the cause of    1402 Instead, an abort (data abort if the cause of the page-table update
1403 was a load or a store, instruction abort if i    1403 was a load or a store, instruction abort if it was an instruction
1404 fetch) is injected in the guest.                 1404 fetch) is injected in the guest.
1405                                                  1405 
1406 S390:                                            1406 S390:
1407 ^^^^^                                            1407 ^^^^^
1408                                                  1408 
1409 Returns -EINVAL if the VM has the KVM_VM_S390    1409 Returns -EINVAL if the VM has the KVM_VM_S390_UCONTROL flag set.
1410 Returns -EINVAL if called on a protected VM.     1410 Returns -EINVAL if called on a protected VM.
1411                                                  1411 
1412 4.36 KVM_SET_TSS_ADDR                            1412 4.36 KVM_SET_TSS_ADDR
1413 ---------------------                            1413 ---------------------
1414                                                  1414 
1415 :Capability: KVM_CAP_SET_TSS_ADDR                1415 :Capability: KVM_CAP_SET_TSS_ADDR
1416 :Architectures: x86                              1416 :Architectures: x86
1417 :Type: vm ioctl                                  1417 :Type: vm ioctl
1418 :Parameters: unsigned long tss_address (in)      1418 :Parameters: unsigned long tss_address (in)
1419 :Returns: 0 on success, -1 on error              1419 :Returns: 0 on success, -1 on error
1420                                                  1420 
1421 This ioctl defines the physical address of a     1421 This ioctl defines the physical address of a three-page region in the guest
1422 physical address space.  The region must be w    1422 physical address space.  The region must be within the first 4GB of the
1423 guest physical address space and must not con    1423 guest physical address space and must not conflict with any memory slot
1424 or any mmio address.  The guest may malfuncti    1424 or any mmio address.  The guest may malfunction if it accesses this memory
1425 region.                                          1425 region.
1426                                                  1426 
1427 This ioctl is required on Intel-based hosts.     1427 This ioctl is required on Intel-based hosts.  This is needed on Intel hardware
1428 because of a quirk in the virtualization impl    1428 because of a quirk in the virtualization implementation (see the internals
1429 documentation when it pops into existence).      1429 documentation when it pops into existence).
1430                                                  1430 
1431                                                  1431 
1432 4.37 KVM_ENABLE_CAP                              1432 4.37 KVM_ENABLE_CAP
1433 -------------------                              1433 -------------------
1434                                                  1434 
1435 :Capability: KVM_CAP_ENABLE_CAP                  1435 :Capability: KVM_CAP_ENABLE_CAP
1436 :Architectures: mips, ppc, s390, x86, loongar    1436 :Architectures: mips, ppc, s390, x86, loongarch
1437 :Type: vcpu ioctl                                1437 :Type: vcpu ioctl
1438 :Parameters: struct kvm_enable_cap (in)          1438 :Parameters: struct kvm_enable_cap (in)
1439 :Returns: 0 on success; -1 on error              1439 :Returns: 0 on success; -1 on error
1440                                                  1440 
1441 :Capability: KVM_CAP_ENABLE_CAP_VM               1441 :Capability: KVM_CAP_ENABLE_CAP_VM
1442 :Architectures: all                              1442 :Architectures: all
1443 :Type: vm ioctl                                  1443 :Type: vm ioctl
1444 :Parameters: struct kvm_enable_cap (in)          1444 :Parameters: struct kvm_enable_cap (in)
1445 :Returns: 0 on success; -1 on error              1445 :Returns: 0 on success; -1 on error
1446                                                  1446 
1447 .. note::                                        1447 .. note::
1448                                                  1448 
1449    Not all extensions are enabled by default.    1449    Not all extensions are enabled by default. Using this ioctl the application
1450    can enable an extension, making it availab    1450    can enable an extension, making it available to the guest.
1451                                                  1451 
1452 On systems that do not support this ioctl, it    1452 On systems that do not support this ioctl, it always fails. On systems that
1453 do support it, it only works for extensions t    1453 do support it, it only works for extensions that are supported for enablement.
1454                                                  1454 
1455 To check if a capability can be enabled, the     1455 To check if a capability can be enabled, the KVM_CHECK_EXTENSION ioctl should
1456 be used.                                         1456 be used.
1457                                                  1457 
1458 ::                                               1458 ::
1459                                                  1459 
1460   struct kvm_enable_cap {                        1460   struct kvm_enable_cap {
1461        /* in */                                  1461        /* in */
1462        __u32 cap;                                1462        __u32 cap;
1463                                                  1463 
1464 The capability that is supposed to get enable    1464 The capability that is supposed to get enabled.
1465                                                  1465 
1466 ::                                               1466 ::
1467                                                  1467 
1468        __u32 flags;                              1468        __u32 flags;
1469                                                  1469 
1470 A bitfield indicating future enhancements. Ha    1470 A bitfield indicating future enhancements. Has to be 0 for now.
1471                                                  1471 
1472 ::                                               1472 ::
1473                                                  1473 
1474        __u64 args[4];                            1474        __u64 args[4];
1475                                                  1475 
1476 Arguments for enabling a feature. If a featur    1476 Arguments for enabling a feature. If a feature needs initial values to
1477 function properly, this is the place to put t    1477 function properly, this is the place to put them.
1478                                                  1478 
1479 ::                                               1479 ::
1480                                                  1480 
1481        __u8  pad[64];                            1481        __u8  pad[64];
1482   };                                             1482   };
1483                                                  1483 
1484 The vcpu ioctl should be used for vcpu-specif    1484 The vcpu ioctl should be used for vcpu-specific capabilities, the vm ioctl
1485 for vm-wide capabilities.                        1485 for vm-wide capabilities.
1486                                                  1486 
1487 4.38 KVM_GET_MP_STATE                            1487 4.38 KVM_GET_MP_STATE
1488 ---------------------                            1488 ---------------------
1489                                                  1489 
1490 :Capability: KVM_CAP_MP_STATE                    1490 :Capability: KVM_CAP_MP_STATE
1491 :Architectures: x86, s390, arm64, riscv, loon    1491 :Architectures: x86, s390, arm64, riscv, loongarch
1492 :Type: vcpu ioctl                                1492 :Type: vcpu ioctl
1493 :Parameters: struct kvm_mp_state (out)           1493 :Parameters: struct kvm_mp_state (out)
1494 :Returns: 0 on success; -1 on error              1494 :Returns: 0 on success; -1 on error
1495                                                  1495 
1496 ::                                               1496 ::
1497                                                  1497 
1498   struct kvm_mp_state {                          1498   struct kvm_mp_state {
1499         __u32 mp_state;                          1499         __u32 mp_state;
1500   };                                             1500   };
1501                                                  1501 
1502 Returns the vcpu's current "multiprocessing s    1502 Returns the vcpu's current "multiprocessing state" (though also valid on
1503 uniprocessor guests).                            1503 uniprocessor guests).
1504                                                  1504 
1505 Possible values are:                             1505 Possible values are:
1506                                                  1506 
1507    ==========================    ============    1507    ==========================    ===============================================
1508    KVM_MP_STATE_RUNNABLE         the vcpu is     1508    KVM_MP_STATE_RUNNABLE         the vcpu is currently running
1509                                  [x86,arm64,r    1509                                  [x86,arm64,riscv,loongarch]
1510    KVM_MP_STATE_UNINITIALIZED    the vcpu is     1510    KVM_MP_STATE_UNINITIALIZED    the vcpu is an application processor (AP)
1511                                  which has no    1511                                  which has not yet received an INIT signal [x86]
1512    KVM_MP_STATE_INIT_RECEIVED    the vcpu has    1512    KVM_MP_STATE_INIT_RECEIVED    the vcpu has received an INIT signal, and is
1513                                  now ready fo    1513                                  now ready for a SIPI [x86]
1514    KVM_MP_STATE_HALTED           the vcpu has    1514    KVM_MP_STATE_HALTED           the vcpu has executed a HLT instruction and
1515                                  is waiting f    1515                                  is waiting for an interrupt [x86]
1516    KVM_MP_STATE_SIPI_RECEIVED    the vcpu has    1516    KVM_MP_STATE_SIPI_RECEIVED    the vcpu has just received a SIPI (vector
1517                                  accessible v    1517                                  accessible via KVM_GET_VCPU_EVENTS) [x86]
1518    KVM_MP_STATE_STOPPED          the vcpu is     1518    KVM_MP_STATE_STOPPED          the vcpu is stopped [s390,arm64,riscv]
1519    KVM_MP_STATE_CHECK_STOP       the vcpu is     1519    KVM_MP_STATE_CHECK_STOP       the vcpu is in a special error state [s390]
1520    KVM_MP_STATE_OPERATING        the vcpu is     1520    KVM_MP_STATE_OPERATING        the vcpu is operating (running or halted)
1521                                  [s390]          1521                                  [s390]
1522    KVM_MP_STATE_LOAD             the vcpu is     1522    KVM_MP_STATE_LOAD             the vcpu is in a special load/startup state
1523                                  [s390]          1523                                  [s390]
1524    KVM_MP_STATE_SUSPENDED        the vcpu is     1524    KVM_MP_STATE_SUSPENDED        the vcpu is in a suspend state and is waiting
1525                                  for a wakeup    1525                                  for a wakeup event [arm64]
1526    ==========================    ============    1526    ==========================    ===============================================
1527                                                  1527 
1528 On x86, this ioctl is only useful after KVM_C    1528 On x86, this ioctl is only useful after KVM_CREATE_IRQCHIP. Without an
1529 in-kernel irqchip, the multiprocessing state     1529 in-kernel irqchip, the multiprocessing state must be maintained by userspace on
1530 these architectures.                             1530 these architectures.
1531                                                  1531 
1532 For arm64:                                       1532 For arm64:
1533 ^^^^^^^^^^                                       1533 ^^^^^^^^^^
1534                                                  1534 
1535 If a vCPU is in the KVM_MP_STATE_SUSPENDED st    1535 If a vCPU is in the KVM_MP_STATE_SUSPENDED state, KVM will emulate the
1536 architectural execution of a WFI instruction.    1536 architectural execution of a WFI instruction.
1537                                                  1537 
1538 If a wakeup event is recognized, KVM will exi    1538 If a wakeup event is recognized, KVM will exit to userspace with a
1539 KVM_SYSTEM_EVENT exit, where the event type i    1539 KVM_SYSTEM_EVENT exit, where the event type is KVM_SYSTEM_EVENT_WAKEUP. If
1540 userspace wants to honor the wakeup, it must     1540 userspace wants to honor the wakeup, it must set the vCPU's MP state to
1541 KVM_MP_STATE_RUNNABLE. If it does not, KVM wi    1541 KVM_MP_STATE_RUNNABLE. If it does not, KVM will continue to await a wakeup
1542 event in subsequent calls to KVM_RUN.            1542 event in subsequent calls to KVM_RUN.
1543                                                  1543 
1544 .. warning::                                     1544 .. warning::
1545                                                  1545 
1546      If userspace intends to keep the vCPU in    1546      If userspace intends to keep the vCPU in a SUSPENDED state, it is
1547      strongly recommended that userspace take    1547      strongly recommended that userspace take action to suppress the
1548      wakeup event (such as masking an interru    1548      wakeup event (such as masking an interrupt). Otherwise, subsequent
1549      calls to KVM_RUN will immediately exit w    1549      calls to KVM_RUN will immediately exit with a KVM_SYSTEM_EVENT_WAKEUP
1550      event and inadvertently waste CPU cycles    1550      event and inadvertently waste CPU cycles.
1551                                                  1551 
1552      Additionally, if userspace takes action     1552      Additionally, if userspace takes action to suppress a wakeup event,
1553      it is strongly recommended that it also     1553      it is strongly recommended that it also restores the vCPU to its
1554      original state when the vCPU is made RUN    1554      original state when the vCPU is made RUNNABLE again. For example,
1555      if userspace masked a pending interrupt     1555      if userspace masked a pending interrupt to suppress the wakeup,
1556      the interrupt should be unmasked before     1556      the interrupt should be unmasked before returning control to the
1557      guest.                                      1557      guest.
1558                                                  1558 
1559 For riscv:                                       1559 For riscv:
1560 ^^^^^^^^^^                                       1560 ^^^^^^^^^^
1561                                                  1561 
1562 The only states that are valid are KVM_MP_STA    1562 The only states that are valid are KVM_MP_STATE_STOPPED and
1563 KVM_MP_STATE_RUNNABLE which reflect if the vc    1563 KVM_MP_STATE_RUNNABLE which reflect if the vcpu is paused or not.
1564                                                  1564 
1565 On LoongArch, only the KVM_MP_STATE_RUNNABLE     1565 On LoongArch, only the KVM_MP_STATE_RUNNABLE state is used to reflect
1566 whether the vcpu is runnable.                    1566 whether the vcpu is runnable.
1567                                                  1567 
1568 4.39 KVM_SET_MP_STATE                            1568 4.39 KVM_SET_MP_STATE
1569 ---------------------                            1569 ---------------------
1570                                                  1570 
1571 :Capability: KVM_CAP_MP_STATE                    1571 :Capability: KVM_CAP_MP_STATE
1572 :Architectures: x86, s390, arm64, riscv, loon    1572 :Architectures: x86, s390, arm64, riscv, loongarch
1573 :Type: vcpu ioctl                                1573 :Type: vcpu ioctl
1574 :Parameters: struct kvm_mp_state (in)            1574 :Parameters: struct kvm_mp_state (in)
1575 :Returns: 0 on success; -1 on error              1575 :Returns: 0 on success; -1 on error
1576                                                  1576 
1577 Sets the vcpu's current "multiprocessing stat    1577 Sets the vcpu's current "multiprocessing state"; see KVM_GET_MP_STATE for
1578 arguments.                                       1578 arguments.
1579                                                  1579 
1580 On x86, this ioctl is only useful after KVM_C    1580 On x86, this ioctl is only useful after KVM_CREATE_IRQCHIP. Without an
1581 in-kernel irqchip, the multiprocessing state     1581 in-kernel irqchip, the multiprocessing state must be maintained by userspace on
1582 these architectures.                             1582 these architectures.
1583                                                  1583 
1584 For arm64/riscv:                                 1584 For arm64/riscv:
1585 ^^^^^^^^^^^^^^^^                                 1585 ^^^^^^^^^^^^^^^^
1586                                                  1586 
1587 The only states that are valid are KVM_MP_STA    1587 The only states that are valid are KVM_MP_STATE_STOPPED and
1588 KVM_MP_STATE_RUNNABLE which reflect if the vc    1588 KVM_MP_STATE_RUNNABLE which reflect if the vcpu should be paused or not.
1589                                                  1589 
1590 On LoongArch, only the KVM_MP_STATE_RUNNABLE     1590 On LoongArch, only the KVM_MP_STATE_RUNNABLE state is used to reflect
1591 whether the vcpu is runnable.                    1591 whether the vcpu is runnable.
1592                                                  1592 
1593 4.40 KVM_SET_IDENTITY_MAP_ADDR                   1593 4.40 KVM_SET_IDENTITY_MAP_ADDR
1594 ------------------------------                   1594 ------------------------------
1595                                                  1595 
1596 :Capability: KVM_CAP_SET_IDENTITY_MAP_ADDR       1596 :Capability: KVM_CAP_SET_IDENTITY_MAP_ADDR
1597 :Architectures: x86                              1597 :Architectures: x86
1598 :Type: vm ioctl                                  1598 :Type: vm ioctl
1599 :Parameters: unsigned long identity (in)         1599 :Parameters: unsigned long identity (in)
1600 :Returns: 0 on success, -1 on error              1600 :Returns: 0 on success, -1 on error
1601                                                  1601 
1602 This ioctl defines the physical address of a     1602 This ioctl defines the physical address of a one-page region in the guest
1603 physical address space.  The region must be w    1603 physical address space.  The region must be within the first 4GB of the
1604 guest physical address space and must not con    1604 guest physical address space and must not conflict with any memory slot
1605 or any mmio address.  The guest may malfuncti    1605 or any mmio address.  The guest may malfunction if it accesses this memory
1606 region.                                          1606 region.
1607                                                  1607 
1608 Setting the address to 0 will result in reset    1608 Setting the address to 0 will result in resetting the address to its default
1609 (0xfffbc000).                                    1609 (0xfffbc000).
1610                                                  1610 
1611 This ioctl is required on Intel-based hosts.     1611 This ioctl is required on Intel-based hosts.  This is needed on Intel hardware
1612 because of a quirk in the virtualization impl    1612 because of a quirk in the virtualization implementation (see the internals
1613 documentation when it pops into existence).      1613 documentation when it pops into existence).
1614                                                  1614 
1615 Fails if any VCPU has already been created.      1615 Fails if any VCPU has already been created.
1616                                                  1616 
1617 4.41 KVM_SET_BOOT_CPU_ID                         1617 4.41 KVM_SET_BOOT_CPU_ID
1618 ------------------------                         1618 ------------------------
1619                                                  1619 
1620 :Capability: KVM_CAP_SET_BOOT_CPU_ID             1620 :Capability: KVM_CAP_SET_BOOT_CPU_ID
1621 :Architectures: x86                              1621 :Architectures: x86
1622 :Type: vm ioctl                                  1622 :Type: vm ioctl
1623 :Parameters: unsigned long vcpu_id               1623 :Parameters: unsigned long vcpu_id
1624 :Returns: 0 on success, -1 on error              1624 :Returns: 0 on success, -1 on error
1625                                                  1625 
1626 Define which vcpu is the Bootstrap Processor     1626 Define which vcpu is the Bootstrap Processor (BSP).  Values are the same
1627 as the vcpu id in KVM_CREATE_VCPU.  If this i    1627 as the vcpu id in KVM_CREATE_VCPU.  If this ioctl is not called, the default
1628 is vcpu 0. This ioctl has to be called before    1628 is vcpu 0. This ioctl has to be called before vcpu creation,
1629 otherwise it will return EBUSY error.            1629 otherwise it will return EBUSY error.
1630                                                  1630 
1631                                                  1631 
1632 4.42 KVM_GET_XSAVE                               1632 4.42 KVM_GET_XSAVE
1633 ------------------                               1633 ------------------
1634                                                  1634 
1635 :Capability: KVM_CAP_XSAVE                       1635 :Capability: KVM_CAP_XSAVE
1636 :Architectures: x86                              1636 :Architectures: x86
1637 :Type: vcpu ioctl                                1637 :Type: vcpu ioctl
1638 :Parameters: struct kvm_xsave (out)              1638 :Parameters: struct kvm_xsave (out)
1639 :Returns: 0 on success, -1 on error              1639 :Returns: 0 on success, -1 on error
1640                                                  1640 
1641                                                  1641 
1642 ::                                               1642 ::
1643                                                  1643 
1644   struct kvm_xsave {                             1644   struct kvm_xsave {
1645         __u32 region[1024];                      1645         __u32 region[1024];
1646         __u32 extra[0];                          1646         __u32 extra[0];
1647   };                                             1647   };
1648                                                  1648 
1649 This ioctl would copy current vcpu's xsave st    1649 This ioctl would copy current vcpu's xsave struct to the userspace.
1650                                                  1650 
1651                                                  1651 
1652 4.43 KVM_SET_XSAVE                               1652 4.43 KVM_SET_XSAVE
1653 ------------------                               1653 ------------------
1654                                                  1654 
1655 :Capability: KVM_CAP_XSAVE and KVM_CAP_XSAVE2    1655 :Capability: KVM_CAP_XSAVE and KVM_CAP_XSAVE2
1656 :Architectures: x86                              1656 :Architectures: x86
1657 :Type: vcpu ioctl                                1657 :Type: vcpu ioctl
1658 :Parameters: struct kvm_xsave (in)               1658 :Parameters: struct kvm_xsave (in)
1659 :Returns: 0 on success, -1 on error              1659 :Returns: 0 on success, -1 on error
1660                                                  1660 
1661 ::                                               1661 ::
1662                                                  1662 
1663                                                  1663 
1664   struct kvm_xsave {                             1664   struct kvm_xsave {
1665         __u32 region[1024];                      1665         __u32 region[1024];
1666         __u32 extra[0];                          1666         __u32 extra[0];
1667   };                                             1667   };
1668                                                  1668 
1669 This ioctl would copy userspace's xsave struc    1669 This ioctl would copy userspace's xsave struct to the kernel. It copies
1670 as many bytes as are returned by KVM_CHECK_EX    1670 as many bytes as are returned by KVM_CHECK_EXTENSION(KVM_CAP_XSAVE2),
1671 when invoked on the vm file descriptor. The s    1671 when invoked on the vm file descriptor. The size value returned by
1672 KVM_CHECK_EXTENSION(KVM_CAP_XSAVE2) will alwa    1672 KVM_CHECK_EXTENSION(KVM_CAP_XSAVE2) will always be at least 4096.
1673 Currently, it is only greater than 4096 if a     1673 Currently, it is only greater than 4096 if a dynamic feature has been
1674 enabled with ``arch_prctl()``, but this may c    1674 enabled with ``arch_prctl()``, but this may change in the future.
1675                                                  1675 
1676 The offsets of the state save areas in struct    1676 The offsets of the state save areas in struct kvm_xsave follow the
1677 contents of CPUID leaf 0xD on the host.          1677 contents of CPUID leaf 0xD on the host.
1678                                                  1678 
1679                                                  1679 
1680 4.44 KVM_GET_XCRS                                1680 4.44 KVM_GET_XCRS
1681 -----------------                                1681 -----------------
1682                                                  1682 
1683 :Capability: KVM_CAP_XCRS                        1683 :Capability: KVM_CAP_XCRS
1684 :Architectures: x86                              1684 :Architectures: x86
1685 :Type: vcpu ioctl                                1685 :Type: vcpu ioctl
1686 :Parameters: struct kvm_xcrs (out)               1686 :Parameters: struct kvm_xcrs (out)
1687 :Returns: 0 on success, -1 on error              1687 :Returns: 0 on success, -1 on error
1688                                                  1688 
1689 ::                                               1689 ::
1690                                                  1690 
1691   struct kvm_xcr {                               1691   struct kvm_xcr {
1692         __u32 xcr;                               1692         __u32 xcr;
1693         __u32 reserved;                          1693         __u32 reserved;
1694         __u64 value;                             1694         __u64 value;
1695   };                                             1695   };
1696                                                  1696 
1697   struct kvm_xcrs {                              1697   struct kvm_xcrs {
1698         __u32 nr_xcrs;                           1698         __u32 nr_xcrs;
1699         __u32 flags;                             1699         __u32 flags;
1700         struct kvm_xcr xcrs[KVM_MAX_XCRS];       1700         struct kvm_xcr xcrs[KVM_MAX_XCRS];
1701         __u64 padding[16];                       1701         __u64 padding[16];
1702   };                                             1702   };
1703                                                  1703 
1704 This ioctl would copy current vcpu's xcrs to     1704 This ioctl would copy current vcpu's xcrs to the userspace.
1705                                                  1705 
1706                                                  1706 
1707 4.45 KVM_SET_XCRS                                1707 4.45 KVM_SET_XCRS
1708 -----------------                                1708 -----------------
1709                                                  1709 
1710 :Capability: KVM_CAP_XCRS                        1710 :Capability: KVM_CAP_XCRS
1711 :Architectures: x86                              1711 :Architectures: x86
1712 :Type: vcpu ioctl                                1712 :Type: vcpu ioctl
1713 :Parameters: struct kvm_xcrs (in)                1713 :Parameters: struct kvm_xcrs (in)
1714 :Returns: 0 on success, -1 on error              1714 :Returns: 0 on success, -1 on error
1715                                                  1715 
1716 ::                                               1716 ::
1717                                                  1717 
1718   struct kvm_xcr {                               1718   struct kvm_xcr {
1719         __u32 xcr;                               1719         __u32 xcr;
1720         __u32 reserved;                          1720         __u32 reserved;
1721         __u64 value;                             1721         __u64 value;
1722   };                                             1722   };
1723                                                  1723 
1724   struct kvm_xcrs {                              1724   struct kvm_xcrs {
1725         __u32 nr_xcrs;                           1725         __u32 nr_xcrs;
1726         __u32 flags;                             1726         __u32 flags;
1727         struct kvm_xcr xcrs[KVM_MAX_XCRS];       1727         struct kvm_xcr xcrs[KVM_MAX_XCRS];
1728         __u64 padding[16];                       1728         __u64 padding[16];
1729   };                                             1729   };
1730                                                  1730 
1731 This ioctl would set vcpu's xcr to the value     1731 This ioctl would set vcpu's xcr to the value userspace specified.
1732                                                  1732 
1733                                                  1733 
1734 4.46 KVM_GET_SUPPORTED_CPUID                     1734 4.46 KVM_GET_SUPPORTED_CPUID
1735 ----------------------------                     1735 ----------------------------
1736                                                  1736 
1737 :Capability: KVM_CAP_EXT_CPUID                   1737 :Capability: KVM_CAP_EXT_CPUID
1738 :Architectures: x86                              1738 :Architectures: x86
1739 :Type: system ioctl                              1739 :Type: system ioctl
1740 :Parameters: struct kvm_cpuid2 (in/out)          1740 :Parameters: struct kvm_cpuid2 (in/out)
1741 :Returns: 0 on success, -1 on error              1741 :Returns: 0 on success, -1 on error
1742                                                  1742 
1743 ::                                               1743 ::
1744                                                  1744 
1745   struct kvm_cpuid2 {                            1745   struct kvm_cpuid2 {
1746         __u32 nent;                              1746         __u32 nent;
1747         __u32 padding;                           1747         __u32 padding;
1748         struct kvm_cpuid_entry2 entries[0];      1748         struct kvm_cpuid_entry2 entries[0];
1749   };                                             1749   };
1750                                                  1750 
1751   #define KVM_CPUID_FLAG_SIGNIFCANT_INDEX        1751   #define KVM_CPUID_FLAG_SIGNIFCANT_INDEX               BIT(0)
1752   #define KVM_CPUID_FLAG_STATEFUL_FUNC           1752   #define KVM_CPUID_FLAG_STATEFUL_FUNC          BIT(1) /* deprecated */
1753   #define KVM_CPUID_FLAG_STATE_READ_NEXT         1753   #define KVM_CPUID_FLAG_STATE_READ_NEXT                BIT(2) /* deprecated */
1754                                                  1754 
1755   struct kvm_cpuid_entry2 {                      1755   struct kvm_cpuid_entry2 {
1756         __u32 function;                          1756         __u32 function;
1757         __u32 index;                             1757         __u32 index;
1758         __u32 flags;                             1758         __u32 flags;
1759         __u32 eax;                               1759         __u32 eax;
1760         __u32 ebx;                               1760         __u32 ebx;
1761         __u32 ecx;                               1761         __u32 ecx;
1762         __u32 edx;                               1762         __u32 edx;
1763         __u32 padding[3];                        1763         __u32 padding[3];
1764   };                                             1764   };
1765                                                  1765 
1766 This ioctl returns x86 cpuid features which a    1766 This ioctl returns x86 cpuid features which are supported by both the
1767 hardware and kvm in its default configuration    1767 hardware and kvm in its default configuration.  Userspace can use the
1768 information returned by this ioctl to constru    1768 information returned by this ioctl to construct cpuid information (for
1769 KVM_SET_CPUID2) that is consistent with hardw    1769 KVM_SET_CPUID2) that is consistent with hardware, kernel, and
1770 userspace capabilities, and with user require    1770 userspace capabilities, and with user requirements (for example, the
1771 user may wish to constrain cpuid to emulate o    1771 user may wish to constrain cpuid to emulate older hardware, or for
1772 feature consistency across a cluster).           1772 feature consistency across a cluster).
1773                                                  1773 
1774 Dynamically-enabled feature bits need to be r    1774 Dynamically-enabled feature bits need to be requested with
1775 ``arch_prctl()`` before calling this ioctl. F    1775 ``arch_prctl()`` before calling this ioctl. Feature bits that have not
1776 been requested are excluded from the result.     1776 been requested are excluded from the result.
1777                                                  1777 
1778 Note that certain capabilities, such as KVM_C    1778 Note that certain capabilities, such as KVM_CAP_X86_DISABLE_EXITS, may
1779 expose cpuid features (e.g. MONITOR) which ar    1779 expose cpuid features (e.g. MONITOR) which are not supported by kvm in
1780 its default configuration. If userspace enabl    1780 its default configuration. If userspace enables such capabilities, it
1781 is responsible for modifying the results of t    1781 is responsible for modifying the results of this ioctl appropriately.
1782                                                  1782 
1783 Userspace invokes KVM_GET_SUPPORTED_CPUID by     1783 Userspace invokes KVM_GET_SUPPORTED_CPUID by passing a kvm_cpuid2 structure
1784 with the 'nent' field indicating the number o    1784 with the 'nent' field indicating the number of entries in the variable-size
1785 array 'entries'.  If the number of entries is    1785 array 'entries'.  If the number of entries is too low to describe the cpu
1786 capabilities, an error (E2BIG) is returned.      1786 capabilities, an error (E2BIG) is returned.  If the number is too high,
1787 the 'nent' field is adjusted and an error (EN    1787 the 'nent' field is adjusted and an error (ENOMEM) is returned.  If the
1788 number is just right, the 'nent' field is adj    1788 number is just right, the 'nent' field is adjusted to the number of valid
1789 entries in the 'entries' array, which is then    1789 entries in the 'entries' array, which is then filled.
1790                                                  1790 
1791 The entries returned are the host cpuid as re    1791 The entries returned are the host cpuid as returned by the cpuid instruction,
1792 with unknown or unsupported features masked o    1792 with unknown or unsupported features masked out.  Some features (for example,
1793 x2apic), may not be present in the host cpu,     1793 x2apic), may not be present in the host cpu, but are exposed by kvm if it can
1794 emulate them efficiently. The fields in each     1794 emulate them efficiently. The fields in each entry are defined as follows:
1795                                                  1795 
1796   function:                                      1796   function:
1797          the eax value used to obtain the ent    1797          the eax value used to obtain the entry
1798                                                  1798 
1799   index:                                         1799   index:
1800          the ecx value used to obtain the ent    1800          the ecx value used to obtain the entry (for entries that are
1801          affected by ecx)                        1801          affected by ecx)
1802                                                  1802 
1803   flags:                                         1803   flags:
1804      an OR of zero or more of the following:     1804      an OR of zero or more of the following:
1805                                                  1805 
1806         KVM_CPUID_FLAG_SIGNIFCANT_INDEX:         1806         KVM_CPUID_FLAG_SIGNIFCANT_INDEX:
1807            if the index field is valid           1807            if the index field is valid
1808                                                  1808 
1809    eax, ebx, ecx, edx:                           1809    eax, ebx, ecx, edx:
1810          the values returned by the cpuid ins    1810          the values returned by the cpuid instruction for
1811          this function/index combination         1811          this function/index combination
1812                                                  1812 
1813 The TSC deadline timer feature (CPUID leaf 1,    1813 The TSC deadline timer feature (CPUID leaf 1, ecx[24]) is always returned
1814 as false, since the feature depends on KVM_CR    1814 as false, since the feature depends on KVM_CREATE_IRQCHIP for local APIC
1815 support.  Instead it is reported via::           1815 support.  Instead it is reported via::
1816                                                  1816 
1817   ioctl(KVM_CHECK_EXTENSION, KVM_CAP_TSC_DEAD    1817   ioctl(KVM_CHECK_EXTENSION, KVM_CAP_TSC_DEADLINE_TIMER)
1818                                                  1818 
1819 if that returns true and you use KVM_CREATE_I    1819 if that returns true and you use KVM_CREATE_IRQCHIP, or if you emulate the
1820 feature in userspace, then you can enable the    1820 feature in userspace, then you can enable the feature for KVM_SET_CPUID2.
1821                                                  1821 
1822                                                  1822 
1823 4.47 KVM_PPC_GET_PVINFO                          1823 4.47 KVM_PPC_GET_PVINFO
1824 -----------------------                          1824 -----------------------
1825                                                  1825 
1826 :Capability: KVM_CAP_PPC_GET_PVINFO              1826 :Capability: KVM_CAP_PPC_GET_PVINFO
1827 :Architectures: ppc                              1827 :Architectures: ppc
1828 :Type: vm ioctl                                  1828 :Type: vm ioctl
1829 :Parameters: struct kvm_ppc_pvinfo (out)         1829 :Parameters: struct kvm_ppc_pvinfo (out)
1830 :Returns: 0 on success, !0 on error              1830 :Returns: 0 on success, !0 on error
1831                                                  1831 
1832 ::                                               1832 ::
1833                                                  1833 
1834   struct kvm_ppc_pvinfo {                        1834   struct kvm_ppc_pvinfo {
1835         __u32 flags;                             1835         __u32 flags;
1836         __u32 hcall[4];                          1836         __u32 hcall[4];
1837         __u8  pad[108];                          1837         __u8  pad[108];
1838   };                                             1838   };
1839                                                  1839 
1840 This ioctl fetches PV specific information th    1840 This ioctl fetches PV specific information that need to be passed to the guest
1841 using the device tree or other means from vm     1841 using the device tree or other means from vm context.
1842                                                  1842 
1843 The hcall array defines 4 instructions that m    1843 The hcall array defines 4 instructions that make up a hypercall.
1844                                                  1844 
1845 If any additional field gets added to this st    1845 If any additional field gets added to this structure later on, a bit for that
1846 additional piece of information will be set i    1846 additional piece of information will be set in the flags bitmap.
1847                                                  1847 
1848 The flags bitmap is defined as::                 1848 The flags bitmap is defined as::
1849                                                  1849 
1850    /* the host supports the ePAPR idle hcall     1850    /* the host supports the ePAPR idle hcall
1851    #define KVM_PPC_PVINFO_FLAGS_EV_IDLE   (1<    1851    #define KVM_PPC_PVINFO_FLAGS_EV_IDLE   (1<<0)
1852                                                  1852 
1853 4.52 KVM_SET_GSI_ROUTING                         1853 4.52 KVM_SET_GSI_ROUTING
1854 ------------------------                         1854 ------------------------
1855                                                  1855 
1856 :Capability: KVM_CAP_IRQ_ROUTING                 1856 :Capability: KVM_CAP_IRQ_ROUTING
1857 :Architectures: x86 s390 arm64                   1857 :Architectures: x86 s390 arm64
1858 :Type: vm ioctl                                  1858 :Type: vm ioctl
1859 :Parameters: struct kvm_irq_routing (in)         1859 :Parameters: struct kvm_irq_routing (in)
1860 :Returns: 0 on success, -1 on error              1860 :Returns: 0 on success, -1 on error
1861                                                  1861 
1862 Sets the GSI routing table entries, overwriti    1862 Sets the GSI routing table entries, overwriting any previously set entries.
1863                                                  1863 
1864 On arm64, GSI routing has the following limit    1864 On arm64, GSI routing has the following limitation:
1865                                                  1865 
1866 - GSI routing does not apply to KVM_IRQ_LINE     1866 - GSI routing does not apply to KVM_IRQ_LINE but only to KVM_IRQFD.
1867                                                  1867 
1868 ::                                               1868 ::
1869                                                  1869 
1870   struct kvm_irq_routing {                       1870   struct kvm_irq_routing {
1871         __u32 nr;                                1871         __u32 nr;
1872         __u32 flags;                             1872         __u32 flags;
1873         struct kvm_irq_routing_entry entries[    1873         struct kvm_irq_routing_entry entries[0];
1874   };                                             1874   };
1875                                                  1875 
1876 No flags are specified so far, the correspond    1876 No flags are specified so far, the corresponding field must be set to zero.
1877                                                  1877 
1878 ::                                               1878 ::
1879                                                  1879 
1880   struct kvm_irq_routing_entry {                 1880   struct kvm_irq_routing_entry {
1881         __u32 gsi;                               1881         __u32 gsi;
1882         __u32 type;                              1882         __u32 type;
1883         __u32 flags;                             1883         __u32 flags;
1884         __u32 pad;                               1884         __u32 pad;
1885         union {                                  1885         union {
1886                 struct kvm_irq_routing_irqchi    1886                 struct kvm_irq_routing_irqchip irqchip;
1887                 struct kvm_irq_routing_msi ms    1887                 struct kvm_irq_routing_msi msi;
1888                 struct kvm_irq_routing_s390_a    1888                 struct kvm_irq_routing_s390_adapter adapter;
1889                 struct kvm_irq_routing_hv_sin    1889                 struct kvm_irq_routing_hv_sint hv_sint;
1890                 struct kvm_irq_routing_xen_ev    1890                 struct kvm_irq_routing_xen_evtchn xen_evtchn;
1891                 __u32 pad[8];                    1891                 __u32 pad[8];
1892         } u;                                     1892         } u;
1893   };                                             1893   };
1894                                                  1894 
1895   /* gsi routing entry types */                  1895   /* gsi routing entry types */
1896   #define KVM_IRQ_ROUTING_IRQCHIP 1              1896   #define KVM_IRQ_ROUTING_IRQCHIP 1
1897   #define KVM_IRQ_ROUTING_MSI 2                  1897   #define KVM_IRQ_ROUTING_MSI 2
1898   #define KVM_IRQ_ROUTING_S390_ADAPTER 3         1898   #define KVM_IRQ_ROUTING_S390_ADAPTER 3
1899   #define KVM_IRQ_ROUTING_HV_SINT 4              1899   #define KVM_IRQ_ROUTING_HV_SINT 4
1900   #define KVM_IRQ_ROUTING_XEN_EVTCHN 5           1900   #define KVM_IRQ_ROUTING_XEN_EVTCHN 5
1901                                                  1901 
1902 flags:                                           1902 flags:
1903                                                  1903 
1904 - KVM_MSI_VALID_DEVID: used along with KVM_IR    1904 - KVM_MSI_VALID_DEVID: used along with KVM_IRQ_ROUTING_MSI routing entry
1905   type, specifies that the devid field contai    1905   type, specifies that the devid field contains a valid value.  The per-VM
1906   KVM_CAP_MSI_DEVID capability advertises the    1906   KVM_CAP_MSI_DEVID capability advertises the requirement to provide
1907   the device ID.  If this capability is not a    1907   the device ID.  If this capability is not available, userspace should
1908   never set the KVM_MSI_VALID_DEVID flag as t    1908   never set the KVM_MSI_VALID_DEVID flag as the ioctl might fail.
1909 - zero otherwise                                 1909 - zero otherwise
1910                                                  1910 
1911 ::                                               1911 ::
1912                                                  1912 
1913   struct kvm_irq_routing_irqchip {               1913   struct kvm_irq_routing_irqchip {
1914         __u32 irqchip;                           1914         __u32 irqchip;
1915         __u32 pin;                               1915         __u32 pin;
1916   };                                             1916   };
1917                                                  1917 
1918   struct kvm_irq_routing_msi {                   1918   struct kvm_irq_routing_msi {
1919         __u32 address_lo;                        1919         __u32 address_lo;
1920         __u32 address_hi;                        1920         __u32 address_hi;
1921         __u32 data;                              1921         __u32 data;
1922         union {                                  1922         union {
1923                 __u32 pad;                       1923                 __u32 pad;
1924                 __u32 devid;                     1924                 __u32 devid;
1925         };                                       1925         };
1926   };                                             1926   };
1927                                                  1927 
1928 If KVM_MSI_VALID_DEVID is set, devid contains    1928 If KVM_MSI_VALID_DEVID is set, devid contains a unique device identifier
1929 for the device that wrote the MSI message.  F    1929 for the device that wrote the MSI message.  For PCI, this is usually a
1930 BDF identifier in the lower 16 bits.             1930 BDF identifier in the lower 16 bits.
1931                                                  1931 
1932 On x86, address_hi is ignored unless the KVM_    1932 On x86, address_hi is ignored unless the KVM_X2APIC_API_USE_32BIT_IDS
1933 feature of KVM_CAP_X2APIC_API capability is e    1933 feature of KVM_CAP_X2APIC_API capability is enabled.  If it is enabled,
1934 address_hi bits 31-8 provide bits 31-8 of the    1934 address_hi bits 31-8 provide bits 31-8 of the destination id.  Bits 7-0 of
1935 address_hi must be zero.                         1935 address_hi must be zero.
1936                                                  1936 
1937 ::                                               1937 ::
1938                                                  1938 
1939   struct kvm_irq_routing_s390_adapter {          1939   struct kvm_irq_routing_s390_adapter {
1940         __u64 ind_addr;                          1940         __u64 ind_addr;
1941         __u64 summary_addr;                      1941         __u64 summary_addr;
1942         __u64 ind_offset;                        1942         __u64 ind_offset;
1943         __u32 summary_offset;                    1943         __u32 summary_offset;
1944         __u32 adapter_id;                        1944         __u32 adapter_id;
1945   };                                             1945   };
1946                                                  1946 
1947   struct kvm_irq_routing_hv_sint {               1947   struct kvm_irq_routing_hv_sint {
1948         __u32 vcpu;                              1948         __u32 vcpu;
1949         __u32 sint;                              1949         __u32 sint;
1950   };                                             1950   };
1951                                                  1951 
1952   struct kvm_irq_routing_xen_evtchn {            1952   struct kvm_irq_routing_xen_evtchn {
1953         __u32 port;                              1953         __u32 port;
1954         __u32 vcpu;                              1954         __u32 vcpu;
1955         __u32 priority;                          1955         __u32 priority;
1956   };                                             1956   };
1957                                                  1957 
1958                                                  1958 
1959 When KVM_CAP_XEN_HVM includes the KVM_XEN_HVM    1959 When KVM_CAP_XEN_HVM includes the KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL bit
1960 in its indication of supported features, rout    1960 in its indication of supported features, routing to Xen event channels
1961 is supported. Although the priority field is     1961 is supported. Although the priority field is present, only the value
1962 KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL is supported    1962 KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL is supported, which means delivery by
1963 2 level event channels. FIFO event channel su    1963 2 level event channels. FIFO event channel support may be added in
1964 the future.                                      1964 the future.
1965                                                  1965 
1966                                                  1966 
1967 4.55 KVM_SET_TSC_KHZ                             1967 4.55 KVM_SET_TSC_KHZ
1968 --------------------                             1968 --------------------
1969                                                  1969 
1970 :Capability: KVM_CAP_TSC_CONTROL / KVM_CAP_VM    1970 :Capability: KVM_CAP_TSC_CONTROL / KVM_CAP_VM_TSC_CONTROL
1971 :Architectures: x86                              1971 :Architectures: x86
1972 :Type: vcpu ioctl / vm ioctl                     1972 :Type: vcpu ioctl / vm ioctl
1973 :Parameters: virtual tsc_khz                     1973 :Parameters: virtual tsc_khz
1974 :Returns: 0 on success, -1 on error              1974 :Returns: 0 on success, -1 on error
1975                                                  1975 
1976 Specifies the tsc frequency for the virtual m    1976 Specifies the tsc frequency for the virtual machine. The unit of the
1977 frequency is KHz.                                1977 frequency is KHz.
1978                                                  1978 
1979 If the KVM_CAP_VM_TSC_CONTROL capability is a    1979 If the KVM_CAP_VM_TSC_CONTROL capability is advertised, this can also
1980 be used as a vm ioctl to set the initial tsc     1980 be used as a vm ioctl to set the initial tsc frequency of subsequently
1981 created vCPUs.                                   1981 created vCPUs.
1982                                                  1982 
1983 4.56 KVM_GET_TSC_KHZ                             1983 4.56 KVM_GET_TSC_KHZ
1984 --------------------                             1984 --------------------
1985                                                  1985 
1986 :Capability: KVM_CAP_GET_TSC_KHZ / KVM_CAP_VM    1986 :Capability: KVM_CAP_GET_TSC_KHZ / KVM_CAP_VM_TSC_CONTROL
1987 :Architectures: x86                              1987 :Architectures: x86
1988 :Type: vcpu ioctl / vm ioctl                     1988 :Type: vcpu ioctl / vm ioctl
1989 :Parameters: none                                1989 :Parameters: none
1990 :Returns: virtual tsc-khz on success, negativ    1990 :Returns: virtual tsc-khz on success, negative value on error
1991                                                  1991 
1992 Returns the tsc frequency of the guest. The u    1992 Returns the tsc frequency of the guest. The unit of the return value is
1993 KHz. If the host has unstable tsc this ioctl     1993 KHz. If the host has unstable tsc this ioctl returns -EIO instead as an
1994 error.                                           1994 error.
1995                                                  1995 
1996                                                  1996 
1997 4.57 KVM_GET_LAPIC                               1997 4.57 KVM_GET_LAPIC
1998 ------------------                               1998 ------------------
1999                                                  1999 
2000 :Capability: KVM_CAP_IRQCHIP                     2000 :Capability: KVM_CAP_IRQCHIP
2001 :Architectures: x86                              2001 :Architectures: x86
2002 :Type: vcpu ioctl                                2002 :Type: vcpu ioctl
2003 :Parameters: struct kvm_lapic_state (out)        2003 :Parameters: struct kvm_lapic_state (out)
2004 :Returns: 0 on success, -1 on error              2004 :Returns: 0 on success, -1 on error
2005                                                  2005 
2006 ::                                               2006 ::
2007                                                  2007 
2008   #define KVM_APIC_REG_SIZE 0x400                2008   #define KVM_APIC_REG_SIZE 0x400
2009   struct kvm_lapic_state {                       2009   struct kvm_lapic_state {
2010         char regs[KVM_APIC_REG_SIZE];            2010         char regs[KVM_APIC_REG_SIZE];
2011   };                                             2011   };
2012                                                  2012 
2013 Reads the Local APIC registers and copies the    2013 Reads the Local APIC registers and copies them into the input argument.  The
2014 data format and layout are the same as docume    2014 data format and layout are the same as documented in the architecture manual.
2015                                                  2015 
2016 If KVM_X2APIC_API_USE_32BIT_IDS feature of KV    2016 If KVM_X2APIC_API_USE_32BIT_IDS feature of KVM_CAP_X2APIC_API is
2017 enabled, then the format of APIC_ID register     2017 enabled, then the format of APIC_ID register depends on the APIC mode
2018 (reported by MSR_IA32_APICBASE) of its VCPU.     2018 (reported by MSR_IA32_APICBASE) of its VCPU.  x2APIC stores APIC ID in
2019 the APIC_ID register (bytes 32-35).  xAPIC on    2019 the APIC_ID register (bytes 32-35).  xAPIC only allows an 8-bit APIC ID
2020 which is stored in bits 31-24 of the APIC reg    2020 which is stored in bits 31-24 of the APIC register, or equivalently in
2021 byte 35 of struct kvm_lapic_state's regs fiel    2021 byte 35 of struct kvm_lapic_state's regs field.  KVM_GET_LAPIC must then
2022 be called after MSR_IA32_APICBASE has been se    2022 be called after MSR_IA32_APICBASE has been set with KVM_SET_MSR.
2023                                                  2023 
2024 If KVM_X2APIC_API_USE_32BIT_IDS feature is di    2024 If KVM_X2APIC_API_USE_32BIT_IDS feature is disabled, struct kvm_lapic_state
2025 always uses xAPIC format.                        2025 always uses xAPIC format.
2026                                                  2026 
2027                                                  2027 
2028 4.58 KVM_SET_LAPIC                               2028 4.58 KVM_SET_LAPIC
2029 ------------------                               2029 ------------------
2030                                                  2030 
2031 :Capability: KVM_CAP_IRQCHIP                     2031 :Capability: KVM_CAP_IRQCHIP
2032 :Architectures: x86                              2032 :Architectures: x86
2033 :Type: vcpu ioctl                                2033 :Type: vcpu ioctl
2034 :Parameters: struct kvm_lapic_state (in)         2034 :Parameters: struct kvm_lapic_state (in)
2035 :Returns: 0 on success, -1 on error              2035 :Returns: 0 on success, -1 on error
2036                                                  2036 
2037 ::                                               2037 ::
2038                                                  2038 
2039   #define KVM_APIC_REG_SIZE 0x400                2039   #define KVM_APIC_REG_SIZE 0x400
2040   struct kvm_lapic_state {                       2040   struct kvm_lapic_state {
2041         char regs[KVM_APIC_REG_SIZE];            2041         char regs[KVM_APIC_REG_SIZE];
2042   };                                             2042   };
2043                                                  2043 
2044 Copies the input argument into the Local APIC    2044 Copies the input argument into the Local APIC registers.  The data format
2045 and layout are the same as documented in the     2045 and layout are the same as documented in the architecture manual.
2046                                                  2046 
2047 The format of the APIC ID register (bytes 32-    2047 The format of the APIC ID register (bytes 32-35 of struct kvm_lapic_state's
2048 regs field) depends on the state of the KVM_C    2048 regs field) depends on the state of the KVM_CAP_X2APIC_API capability.
2049 See the note in KVM_GET_LAPIC.                   2049 See the note in KVM_GET_LAPIC.
2050                                                  2050 
2051                                                  2051 
2052 4.59 KVM_IOEVENTFD                               2052 4.59 KVM_IOEVENTFD
2053 ------------------                               2053 ------------------
2054                                                  2054 
2055 :Capability: KVM_CAP_IOEVENTFD                   2055 :Capability: KVM_CAP_IOEVENTFD
2056 :Architectures: all                              2056 :Architectures: all
2057 :Type: vm ioctl                                  2057 :Type: vm ioctl
2058 :Parameters: struct kvm_ioeventfd (in)           2058 :Parameters: struct kvm_ioeventfd (in)
2059 :Returns: 0 on success, !0 on error              2059 :Returns: 0 on success, !0 on error
2060                                                  2060 
2061 This ioctl attaches or detaches an ioeventfd     2061 This ioctl attaches or detaches an ioeventfd to a legal pio/mmio address
2062 within the guest.  A guest write in the regis    2062 within the guest.  A guest write in the registered address will signal the
2063 provided event instead of triggering an exit.    2063 provided event instead of triggering an exit.
2064                                                  2064 
2065 ::                                               2065 ::
2066                                                  2066 
2067   struct kvm_ioeventfd {                         2067   struct kvm_ioeventfd {
2068         __u64 datamatch;                         2068         __u64 datamatch;
2069         __u64 addr;        /* legal pio/mmio     2069         __u64 addr;        /* legal pio/mmio address */
2070         __u32 len;         /* 0, 1, 2, 4, or     2070         __u32 len;         /* 0, 1, 2, 4, or 8 bytes    */
2071         __s32 fd;                                2071         __s32 fd;
2072         __u32 flags;                             2072         __u32 flags;
2073         __u8  pad[36];                           2073         __u8  pad[36];
2074   };                                             2074   };
2075                                                  2075 
2076 For the special case of virtio-ccw devices on    2076 For the special case of virtio-ccw devices on s390, the ioevent is matched
2077 to a subchannel/virtqueue tuple instead.         2077 to a subchannel/virtqueue tuple instead.
2078                                                  2078 
2079 The following flags are defined::                2079 The following flags are defined::
2080                                                  2080 
2081   #define KVM_IOEVENTFD_FLAG_DATAMATCH (1 <<     2081   #define KVM_IOEVENTFD_FLAG_DATAMATCH (1 << kvm_ioeventfd_flag_nr_datamatch)
2082   #define KVM_IOEVENTFD_FLAG_PIO       (1 <<     2082   #define KVM_IOEVENTFD_FLAG_PIO       (1 << kvm_ioeventfd_flag_nr_pio)
2083   #define KVM_IOEVENTFD_FLAG_DEASSIGN  (1 <<     2083   #define KVM_IOEVENTFD_FLAG_DEASSIGN  (1 << kvm_ioeventfd_flag_nr_deassign)
2084   #define KVM_IOEVENTFD_FLAG_VIRTIO_CCW_NOTIF    2084   #define KVM_IOEVENTFD_FLAG_VIRTIO_CCW_NOTIFY \
2085         (1 << kvm_ioeventfd_flag_nr_virtio_cc    2085         (1 << kvm_ioeventfd_flag_nr_virtio_ccw_notify)
2086                                                  2086 
2087 If datamatch flag is set, the event will be s    2087 If datamatch flag is set, the event will be signaled only if the written value
2088 to the registered address is equal to datamat    2088 to the registered address is equal to datamatch in struct kvm_ioeventfd.
2089                                                  2089 
2090 For virtio-ccw devices, addr contains the sub    2090 For virtio-ccw devices, addr contains the subchannel id and datamatch the
2091 virtqueue index.                                 2091 virtqueue index.
2092                                                  2092 
2093 With KVM_CAP_IOEVENTFD_ANY_LENGTH, a zero len    2093 With KVM_CAP_IOEVENTFD_ANY_LENGTH, a zero length ioeventfd is allowed, and
2094 the kernel will ignore the length of guest wr    2094 the kernel will ignore the length of guest write and may get a faster vmexit.
2095 The speedup may only apply to specific archit    2095 The speedup may only apply to specific architectures, but the ioeventfd will
2096 work anyway.                                     2096 work anyway.
2097                                                  2097 
2098 4.60 KVM_DIRTY_TLB                               2098 4.60 KVM_DIRTY_TLB
2099 ------------------                               2099 ------------------
2100                                                  2100 
2101 :Capability: KVM_CAP_SW_TLB                      2101 :Capability: KVM_CAP_SW_TLB
2102 :Architectures: ppc                              2102 :Architectures: ppc
2103 :Type: vcpu ioctl                                2103 :Type: vcpu ioctl
2104 :Parameters: struct kvm_dirty_tlb (in)           2104 :Parameters: struct kvm_dirty_tlb (in)
2105 :Returns: 0 on success, -1 on error              2105 :Returns: 0 on success, -1 on error
2106                                                  2106 
2107 ::                                               2107 ::
2108                                                  2108 
2109   struct kvm_dirty_tlb {                         2109   struct kvm_dirty_tlb {
2110         __u64 bitmap;                            2110         __u64 bitmap;
2111         __u32 num_dirty;                         2111         __u32 num_dirty;
2112   };                                             2112   };
2113                                                  2113 
2114 This must be called whenever userspace has ch    2114 This must be called whenever userspace has changed an entry in the shared
2115 TLB, prior to calling KVM_RUN on the associat    2115 TLB, prior to calling KVM_RUN on the associated vcpu.
2116                                                  2116 
2117 The "bitmap" field is the userspace address o    2117 The "bitmap" field is the userspace address of an array.  This array
2118 consists of a number of bits, equal to the to    2118 consists of a number of bits, equal to the total number of TLB entries as
2119 determined by the last successful call to KVM    2119 determined by the last successful call to KVM_CONFIG_TLB, rounded up to the
2120 nearest multiple of 64.                          2120 nearest multiple of 64.
2121                                                  2121 
2122 Each bit corresponds to one TLB entry, ordere    2122 Each bit corresponds to one TLB entry, ordered the same as in the shared TLB
2123 array.                                           2123 array.
2124                                                  2124 
2125 The array is little-endian: the bit 0 is the     2125 The array is little-endian: the bit 0 is the least significant bit of the
2126 first byte, bit 8 is the least significant bi    2126 first byte, bit 8 is the least significant bit of the second byte, etc.
2127 This avoids any complications with differing     2127 This avoids any complications with differing word sizes.
2128                                                  2128 
2129 The "num_dirty" field is a performance hint f    2129 The "num_dirty" field is a performance hint for KVM to determine whether it
2130 should skip processing the bitmap and just in    2130 should skip processing the bitmap and just invalidate everything.  It must
2131 be set to the number of set bits in the bitma    2131 be set to the number of set bits in the bitmap.
2132                                                  2132 
2133                                                  2133 
2134 4.62 KVM_CREATE_SPAPR_TCE                        2134 4.62 KVM_CREATE_SPAPR_TCE
2135 -------------------------                        2135 -------------------------
2136                                                  2136 
2137 :Capability: KVM_CAP_SPAPR_TCE                   2137 :Capability: KVM_CAP_SPAPR_TCE
2138 :Architectures: powerpc                          2138 :Architectures: powerpc
2139 :Type: vm ioctl                                  2139 :Type: vm ioctl
2140 :Parameters: struct kvm_create_spapr_tce (in)    2140 :Parameters: struct kvm_create_spapr_tce (in)
2141 :Returns: file descriptor for manipulating th    2141 :Returns: file descriptor for manipulating the created TCE table
2142                                                  2142 
2143 This creates a virtual TCE (translation contr    2143 This creates a virtual TCE (translation control entry) table, which
2144 is an IOMMU for PAPR-style virtual I/O.  It i    2144 is an IOMMU for PAPR-style virtual I/O.  It is used to translate
2145 logical addresses used in virtual I/O into gu    2145 logical addresses used in virtual I/O into guest physical addresses,
2146 and provides a scatter/gather capability for     2146 and provides a scatter/gather capability for PAPR virtual I/O.
2147                                                  2147 
2148 ::                                               2148 ::
2149                                                  2149 
2150   /* for KVM_CAP_SPAPR_TCE */                    2150   /* for KVM_CAP_SPAPR_TCE */
2151   struct kvm_create_spapr_tce {                  2151   struct kvm_create_spapr_tce {
2152         __u64 liobn;                             2152         __u64 liobn;
2153         __u32 window_size;                       2153         __u32 window_size;
2154   };                                             2154   };
2155                                                  2155 
2156 The liobn field gives the logical IO bus numb    2156 The liobn field gives the logical IO bus number for which to create a
2157 TCE table.  The window_size field specifies t    2157 TCE table.  The window_size field specifies the size of the DMA window
2158 which this TCE table will translate - the tab    2158 which this TCE table will translate - the table will contain one 64
2159 bit TCE entry for every 4kiB of the DMA windo    2159 bit TCE entry for every 4kiB of the DMA window.
2160                                                  2160 
2161 When the guest issues an H_PUT_TCE hcall on a    2161 When the guest issues an H_PUT_TCE hcall on a liobn for which a TCE
2162 table has been created using this ioctl(), th    2162 table has been created using this ioctl(), the kernel will handle it
2163 in real mode, updating the TCE table.  H_PUT_    2163 in real mode, updating the TCE table.  H_PUT_TCE calls for other
2164 liobns will cause a vm exit and must be handl    2164 liobns will cause a vm exit and must be handled by userspace.
2165                                                  2165 
2166 The return value is a file descriptor which c    2166 The return value is a file descriptor which can be passed to mmap(2)
2167 to map the created TCE table into userspace.     2167 to map the created TCE table into userspace.  This lets userspace read
2168 the entries written by kernel-handled H_PUT_T    2168 the entries written by kernel-handled H_PUT_TCE calls, and also lets
2169 userspace update the TCE table directly which    2169 userspace update the TCE table directly which is useful in some
2170 circumstances.                                   2170 circumstances.
2171                                                  2171 
2172                                                  2172 
2173 4.63 KVM_ALLOCATE_RMA                            2173 4.63 KVM_ALLOCATE_RMA
2174 ---------------------                            2174 ---------------------
2175                                                  2175 
2176 :Capability: KVM_CAP_PPC_RMA                     2176 :Capability: KVM_CAP_PPC_RMA
2177 :Architectures: powerpc                          2177 :Architectures: powerpc
2178 :Type: vm ioctl                                  2178 :Type: vm ioctl
2179 :Parameters: struct kvm_allocate_rma (out)       2179 :Parameters: struct kvm_allocate_rma (out)
2180 :Returns: file descriptor for mapping the all    2180 :Returns: file descriptor for mapping the allocated RMA
2181                                                  2181 
2182 This allocates a Real Mode Area (RMA) from th    2182 This allocates a Real Mode Area (RMA) from the pool allocated at boot
2183 time by the kernel.  An RMA is a physically-c    2183 time by the kernel.  An RMA is a physically-contiguous, aligned region
2184 of memory used on older POWER processors to p    2184 of memory used on older POWER processors to provide the memory which
2185 will be accessed by real-mode (MMU off) acces    2185 will be accessed by real-mode (MMU off) accesses in a KVM guest.
2186 POWER processors support a set of sizes for t    2186 POWER processors support a set of sizes for the RMA that usually
2187 includes 64MB, 128MB, 256MB and some larger p    2187 includes 64MB, 128MB, 256MB and some larger powers of two.
2188                                                  2188 
2189 ::                                               2189 ::
2190                                                  2190 
2191   /* for KVM_ALLOCATE_RMA */                     2191   /* for KVM_ALLOCATE_RMA */
2192   struct kvm_allocate_rma {                      2192   struct kvm_allocate_rma {
2193         __u64 rma_size;                          2193         __u64 rma_size;
2194   };                                             2194   };
2195                                                  2195 
2196 The return value is a file descriptor which c    2196 The return value is a file descriptor which can be passed to mmap(2)
2197 to map the allocated RMA into userspace.  The    2197 to map the allocated RMA into userspace.  The mapped area can then be
2198 passed to the KVM_SET_USER_MEMORY_REGION ioct    2198 passed to the KVM_SET_USER_MEMORY_REGION ioctl to establish it as the
2199 RMA for a virtual machine.  The size of the R    2199 RMA for a virtual machine.  The size of the RMA in bytes (which is
2200 fixed at host kernel boot time) is returned i    2200 fixed at host kernel boot time) is returned in the rma_size field of
2201 the argument structure.                          2201 the argument structure.
2202                                                  2202 
2203 The KVM_CAP_PPC_RMA capability is 1 or 2 if t    2203 The KVM_CAP_PPC_RMA capability is 1 or 2 if the KVM_ALLOCATE_RMA ioctl
2204 is supported; 2 if the processor requires all    2204 is supported; 2 if the processor requires all virtual machines to have
2205 an RMA, or 1 if the processor can use an RMA     2205 an RMA, or 1 if the processor can use an RMA but doesn't require it,
2206 because it supports the Virtual RMA (VRMA) fa    2206 because it supports the Virtual RMA (VRMA) facility.
2207                                                  2207 
2208                                                  2208 
2209 4.64 KVM_NMI                                     2209 4.64 KVM_NMI
2210 ------------                                     2210 ------------
2211                                                  2211 
2212 :Capability: KVM_CAP_USER_NMI                    2212 :Capability: KVM_CAP_USER_NMI
2213 :Architectures: x86                              2213 :Architectures: x86
2214 :Type: vcpu ioctl                                2214 :Type: vcpu ioctl
2215 :Parameters: none                                2215 :Parameters: none
2216 :Returns: 0 on success, -1 on error              2216 :Returns: 0 on success, -1 on error
2217                                                  2217 
2218 Queues an NMI on the thread's vcpu.  Note thi    2218 Queues an NMI on the thread's vcpu.  Note this is well defined only
2219 when KVM_CREATE_IRQCHIP has not been called,     2219 when KVM_CREATE_IRQCHIP has not been called, since this is an interface
2220 between the virtual cpu core and virtual loca    2220 between the virtual cpu core and virtual local APIC.  After KVM_CREATE_IRQCHIP
2221 has been called, this interface is completely    2221 has been called, this interface is completely emulated within the kernel.
2222                                                  2222 
2223 To use this to emulate the LINT1 input with K    2223 To use this to emulate the LINT1 input with KVM_CREATE_IRQCHIP, use the
2224 following algorithm:                             2224 following algorithm:
2225                                                  2225 
2226   - pause the vcpu                               2226   - pause the vcpu
2227   - read the local APIC's state (KVM_GET_LAPI    2227   - read the local APIC's state (KVM_GET_LAPIC)
2228   - check whether changing LINT1 will queue a    2228   - check whether changing LINT1 will queue an NMI (see the LVT entry for LINT1)
2229   - if so, issue KVM_NMI                         2229   - if so, issue KVM_NMI
2230   - resume the vcpu                              2230   - resume the vcpu
2231                                                  2231 
2232 Some guests configure the LINT1 NMI input to     2232 Some guests configure the LINT1 NMI input to cause a panic, aiding in
2233 debugging.                                       2233 debugging.
2234                                                  2234 
2235                                                  2235 
2236 4.65 KVM_S390_UCAS_MAP                           2236 4.65 KVM_S390_UCAS_MAP
2237 ----------------------                           2237 ----------------------
2238                                                  2238 
2239 :Capability: KVM_CAP_S390_UCONTROL               2239 :Capability: KVM_CAP_S390_UCONTROL
2240 :Architectures: s390                             2240 :Architectures: s390
2241 :Type: vcpu ioctl                                2241 :Type: vcpu ioctl
2242 :Parameters: struct kvm_s390_ucas_mapping (in    2242 :Parameters: struct kvm_s390_ucas_mapping (in)
2243 :Returns: 0 in case of success                   2243 :Returns: 0 in case of success
2244                                                  2244 
2245 The parameter is defined like this::             2245 The parameter is defined like this::
2246                                                  2246 
2247         struct kvm_s390_ucas_mapping {           2247         struct kvm_s390_ucas_mapping {
2248                 __u64 user_addr;                 2248                 __u64 user_addr;
2249                 __u64 vcpu_addr;                 2249                 __u64 vcpu_addr;
2250                 __u64 length;                    2250                 __u64 length;
2251         };                                       2251         };
2252                                                  2252 
2253 This ioctl maps the memory at "user_addr" wit    2253 This ioctl maps the memory at "user_addr" with the length "length" to
2254 the vcpu's address space starting at "vcpu_ad    2254 the vcpu's address space starting at "vcpu_addr". All parameters need to
2255 be aligned by 1 megabyte.                        2255 be aligned by 1 megabyte.
2256                                                  2256 
2257                                                  2257 
2258 4.66 KVM_S390_UCAS_UNMAP                         2258 4.66 KVM_S390_UCAS_UNMAP
2259 ------------------------                         2259 ------------------------
2260                                                  2260 
2261 :Capability: KVM_CAP_S390_UCONTROL               2261 :Capability: KVM_CAP_S390_UCONTROL
2262 :Architectures: s390                             2262 :Architectures: s390
2263 :Type: vcpu ioctl                                2263 :Type: vcpu ioctl
2264 :Parameters: struct kvm_s390_ucas_mapping (in    2264 :Parameters: struct kvm_s390_ucas_mapping (in)
2265 :Returns: 0 in case of success                   2265 :Returns: 0 in case of success
2266                                                  2266 
2267 The parameter is defined like this::             2267 The parameter is defined like this::
2268                                                  2268 
2269         struct kvm_s390_ucas_mapping {           2269         struct kvm_s390_ucas_mapping {
2270                 __u64 user_addr;                 2270                 __u64 user_addr;
2271                 __u64 vcpu_addr;                 2271                 __u64 vcpu_addr;
2272                 __u64 length;                    2272                 __u64 length;
2273         };                                       2273         };
2274                                                  2274 
2275 This ioctl unmaps the memory in the vcpu's ad    2275 This ioctl unmaps the memory in the vcpu's address space starting at
2276 "vcpu_addr" with the length "length". The fie    2276 "vcpu_addr" with the length "length". The field "user_addr" is ignored.
2277 All parameters need to be aligned by 1 megaby    2277 All parameters need to be aligned by 1 megabyte.
2278                                                  2278 
2279                                                  2279 
2280 4.67 KVM_S390_VCPU_FAULT                         2280 4.67 KVM_S390_VCPU_FAULT
2281 ------------------------                         2281 ------------------------
2282                                                  2282 
2283 :Capability: KVM_CAP_S390_UCONTROL               2283 :Capability: KVM_CAP_S390_UCONTROL
2284 :Architectures: s390                             2284 :Architectures: s390
2285 :Type: vcpu ioctl                                2285 :Type: vcpu ioctl
2286 :Parameters: vcpu absolute address (in)          2286 :Parameters: vcpu absolute address (in)
2287 :Returns: 0 in case of success                   2287 :Returns: 0 in case of success
2288                                                  2288 
2289 This call creates a page table entry on the v    2289 This call creates a page table entry on the virtual cpu's address space
2290 (for user controlled virtual machines) or the    2290 (for user controlled virtual machines) or the virtual machine's address
2291 space (for regular virtual machines). This on    2291 space (for regular virtual machines). This only works for minor faults,
2292 thus it's recommended to access subject memor    2292 thus it's recommended to access subject memory page via the user page
2293 table upfront. This is useful to handle valid    2293 table upfront. This is useful to handle validity intercepts for user
2294 controlled virtual machines to fault in the v    2294 controlled virtual machines to fault in the virtual cpu's lowcore pages
2295 prior to calling the KVM_RUN ioctl.              2295 prior to calling the KVM_RUN ioctl.
2296                                                  2296 
2297                                                  2297 
2298 4.68 KVM_SET_ONE_REG                             2298 4.68 KVM_SET_ONE_REG
2299 --------------------                             2299 --------------------
2300                                                  2300 
2301 :Capability: KVM_CAP_ONE_REG                     2301 :Capability: KVM_CAP_ONE_REG
2302 :Architectures: all                              2302 :Architectures: all
2303 :Type: vcpu ioctl                                2303 :Type: vcpu ioctl
2304 :Parameters: struct kvm_one_reg (in)             2304 :Parameters: struct kvm_one_reg (in)
2305 :Returns: 0 on success, negative value on fai    2305 :Returns: 0 on success, negative value on failure
2306                                                  2306 
2307 Errors:                                          2307 Errors:
2308                                                  2308 
2309   ======   ==================================    2309   ======   ============================================================
2310   ENOENT   no such register                      2310   ENOENT   no such register
2311   EINVAL   invalid register ID, or no such re    2311   EINVAL   invalid register ID, or no such register or used with VMs in
2312            protected virtualization mode on s    2312            protected virtualization mode on s390
2313   EPERM    (arm64) register access not allowe    2313   EPERM    (arm64) register access not allowed before vcpu finalization
2314   EBUSY    (riscv) changing register value no    2314   EBUSY    (riscv) changing register value not allowed after the vcpu
2315            has run at least once                 2315            has run at least once
2316   ======   ==================================    2316   ======   ============================================================
2317                                                  2317 
2318 (These error codes are indicative only: do no    2318 (These error codes are indicative only: do not rely on a specific error
2319 code being returned in a specific situation.)    2319 code being returned in a specific situation.)
2320                                                  2320 
2321 ::                                               2321 ::
2322                                                  2322 
2323   struct kvm_one_reg {                           2323   struct kvm_one_reg {
2324        __u64 id;                                 2324        __u64 id;
2325        __u64 addr;                               2325        __u64 addr;
2326  };                                              2326  };
2327                                                  2327 
2328 Using this ioctl, a single vcpu register can     2328 Using this ioctl, a single vcpu register can be set to a specific value
2329 defined by user space with the passed in stru    2329 defined by user space with the passed in struct kvm_one_reg, where id
2330 refers to the register identifier as describe    2330 refers to the register identifier as described below and addr is a pointer
2331 to a variable with the respective size. There    2331 to a variable with the respective size. There can be architecture agnostic
2332 and architecture specific registers. Each hav    2332 and architecture specific registers. Each have their own range of operation
2333 and their own constants and width. To keep tr    2333 and their own constants and width. To keep track of the implemented
2334 registers, find a list below:                    2334 registers, find a list below:
2335                                                  2335 
2336   ======= =============================== ===    2336   ======= =============================== ============
2337   Arch              Register              Wid    2337   Arch              Register              Width (bits)
2338   ======= =============================== ===    2338   ======= =============================== ============
2339   PPC     KVM_REG_PPC_HIOR                64     2339   PPC     KVM_REG_PPC_HIOR                64
2340   PPC     KVM_REG_PPC_IAC1                64     2340   PPC     KVM_REG_PPC_IAC1                64
2341   PPC     KVM_REG_PPC_IAC2                64     2341   PPC     KVM_REG_PPC_IAC2                64
2342   PPC     KVM_REG_PPC_IAC3                64     2342   PPC     KVM_REG_PPC_IAC3                64
2343   PPC     KVM_REG_PPC_IAC4                64     2343   PPC     KVM_REG_PPC_IAC4                64
2344   PPC     KVM_REG_PPC_DAC1                64     2344   PPC     KVM_REG_PPC_DAC1                64
2345   PPC     KVM_REG_PPC_DAC2                64     2345   PPC     KVM_REG_PPC_DAC2                64
2346   PPC     KVM_REG_PPC_DABR                64     2346   PPC     KVM_REG_PPC_DABR                64
2347   PPC     KVM_REG_PPC_DSCR                64     2347   PPC     KVM_REG_PPC_DSCR                64
2348   PPC     KVM_REG_PPC_PURR                64     2348   PPC     KVM_REG_PPC_PURR                64
2349   PPC     KVM_REG_PPC_SPURR               64     2349   PPC     KVM_REG_PPC_SPURR               64
2350   PPC     KVM_REG_PPC_DAR                 64     2350   PPC     KVM_REG_PPC_DAR                 64
2351   PPC     KVM_REG_PPC_DSISR               32     2351   PPC     KVM_REG_PPC_DSISR               32
2352   PPC     KVM_REG_PPC_AMR                 64     2352   PPC     KVM_REG_PPC_AMR                 64
2353   PPC     KVM_REG_PPC_UAMOR               64     2353   PPC     KVM_REG_PPC_UAMOR               64
2354   PPC     KVM_REG_PPC_MMCR0               64     2354   PPC     KVM_REG_PPC_MMCR0               64
2355   PPC     KVM_REG_PPC_MMCR1               64     2355   PPC     KVM_REG_PPC_MMCR1               64
2356   PPC     KVM_REG_PPC_MMCRA               64     2356   PPC     KVM_REG_PPC_MMCRA               64
2357   PPC     KVM_REG_PPC_MMCR2               64     2357   PPC     KVM_REG_PPC_MMCR2               64
2358   PPC     KVM_REG_PPC_MMCRS               64     2358   PPC     KVM_REG_PPC_MMCRS               64
2359   PPC     KVM_REG_PPC_MMCR3               64     2359   PPC     KVM_REG_PPC_MMCR3               64
2360   PPC     KVM_REG_PPC_SIAR                64     2360   PPC     KVM_REG_PPC_SIAR                64
2361   PPC     KVM_REG_PPC_SDAR                64     2361   PPC     KVM_REG_PPC_SDAR                64
2362   PPC     KVM_REG_PPC_SIER                64     2362   PPC     KVM_REG_PPC_SIER                64
2363   PPC     KVM_REG_PPC_SIER2               64     2363   PPC     KVM_REG_PPC_SIER2               64
2364   PPC     KVM_REG_PPC_SIER3               64     2364   PPC     KVM_REG_PPC_SIER3               64
2365   PPC     KVM_REG_PPC_PMC1                32     2365   PPC     KVM_REG_PPC_PMC1                32
2366   PPC     KVM_REG_PPC_PMC2                32     2366   PPC     KVM_REG_PPC_PMC2                32
2367   PPC     KVM_REG_PPC_PMC3                32     2367   PPC     KVM_REG_PPC_PMC3                32
2368   PPC     KVM_REG_PPC_PMC4                32     2368   PPC     KVM_REG_PPC_PMC4                32
2369   PPC     KVM_REG_PPC_PMC5                32     2369   PPC     KVM_REG_PPC_PMC5                32
2370   PPC     KVM_REG_PPC_PMC6                32     2370   PPC     KVM_REG_PPC_PMC6                32
2371   PPC     KVM_REG_PPC_PMC7                32     2371   PPC     KVM_REG_PPC_PMC7                32
2372   PPC     KVM_REG_PPC_PMC8                32     2372   PPC     KVM_REG_PPC_PMC8                32
2373   PPC     KVM_REG_PPC_FPR0                64     2373   PPC     KVM_REG_PPC_FPR0                64
2374   ...                                            2374   ...
2375   PPC     KVM_REG_PPC_FPR31               64     2375   PPC     KVM_REG_PPC_FPR31               64
2376   PPC     KVM_REG_PPC_VR0                 128    2376   PPC     KVM_REG_PPC_VR0                 128
2377   ...                                            2377   ...
2378   PPC     KVM_REG_PPC_VR31                128    2378   PPC     KVM_REG_PPC_VR31                128
2379   PPC     KVM_REG_PPC_VSR0                128    2379   PPC     KVM_REG_PPC_VSR0                128
2380   ...                                            2380   ...
2381   PPC     KVM_REG_PPC_VSR31               128    2381   PPC     KVM_REG_PPC_VSR31               128
2382   PPC     KVM_REG_PPC_FPSCR               64     2382   PPC     KVM_REG_PPC_FPSCR               64
2383   PPC     KVM_REG_PPC_VSCR                32     2383   PPC     KVM_REG_PPC_VSCR                32
2384   PPC     KVM_REG_PPC_VPA_ADDR            64     2384   PPC     KVM_REG_PPC_VPA_ADDR            64
2385   PPC     KVM_REG_PPC_VPA_SLB             128    2385   PPC     KVM_REG_PPC_VPA_SLB             128
2386   PPC     KVM_REG_PPC_VPA_DTL             128    2386   PPC     KVM_REG_PPC_VPA_DTL             128
2387   PPC     KVM_REG_PPC_EPCR                32     2387   PPC     KVM_REG_PPC_EPCR                32
2388   PPC     KVM_REG_PPC_EPR                 32     2388   PPC     KVM_REG_PPC_EPR                 32
2389   PPC     KVM_REG_PPC_TCR                 32     2389   PPC     KVM_REG_PPC_TCR                 32
2390   PPC     KVM_REG_PPC_TSR                 32     2390   PPC     KVM_REG_PPC_TSR                 32
2391   PPC     KVM_REG_PPC_OR_TSR              32     2391   PPC     KVM_REG_PPC_OR_TSR              32
2392   PPC     KVM_REG_PPC_CLEAR_TSR           32     2392   PPC     KVM_REG_PPC_CLEAR_TSR           32
2393   PPC     KVM_REG_PPC_MAS0                32     2393   PPC     KVM_REG_PPC_MAS0                32
2394   PPC     KVM_REG_PPC_MAS1                32     2394   PPC     KVM_REG_PPC_MAS1                32
2395   PPC     KVM_REG_PPC_MAS2                64     2395   PPC     KVM_REG_PPC_MAS2                64
2396   PPC     KVM_REG_PPC_MAS7_3              64     2396   PPC     KVM_REG_PPC_MAS7_3              64
2397   PPC     KVM_REG_PPC_MAS4                32     2397   PPC     KVM_REG_PPC_MAS4                32
2398   PPC     KVM_REG_PPC_MAS6                32     2398   PPC     KVM_REG_PPC_MAS6                32
2399   PPC     KVM_REG_PPC_MMUCFG              32     2399   PPC     KVM_REG_PPC_MMUCFG              32
2400   PPC     KVM_REG_PPC_TLB0CFG             32     2400   PPC     KVM_REG_PPC_TLB0CFG             32
2401   PPC     KVM_REG_PPC_TLB1CFG             32     2401   PPC     KVM_REG_PPC_TLB1CFG             32
2402   PPC     KVM_REG_PPC_TLB2CFG             32     2402   PPC     KVM_REG_PPC_TLB2CFG             32
2403   PPC     KVM_REG_PPC_TLB3CFG             32     2403   PPC     KVM_REG_PPC_TLB3CFG             32
2404   PPC     KVM_REG_PPC_TLB0PS              32     2404   PPC     KVM_REG_PPC_TLB0PS              32
2405   PPC     KVM_REG_PPC_TLB1PS              32     2405   PPC     KVM_REG_PPC_TLB1PS              32
2406   PPC     KVM_REG_PPC_TLB2PS              32     2406   PPC     KVM_REG_PPC_TLB2PS              32
2407   PPC     KVM_REG_PPC_TLB3PS              32     2407   PPC     KVM_REG_PPC_TLB3PS              32
2408   PPC     KVM_REG_PPC_EPTCFG              32     2408   PPC     KVM_REG_PPC_EPTCFG              32
2409   PPC     KVM_REG_PPC_ICP_STATE           64     2409   PPC     KVM_REG_PPC_ICP_STATE           64
2410   PPC     KVM_REG_PPC_VP_STATE            128    2410   PPC     KVM_REG_PPC_VP_STATE            128
2411   PPC     KVM_REG_PPC_TB_OFFSET           64     2411   PPC     KVM_REG_PPC_TB_OFFSET           64
2412   PPC     KVM_REG_PPC_SPMC1               32     2412   PPC     KVM_REG_PPC_SPMC1               32
2413   PPC     KVM_REG_PPC_SPMC2               32     2413   PPC     KVM_REG_PPC_SPMC2               32
2414   PPC     KVM_REG_PPC_IAMR                64     2414   PPC     KVM_REG_PPC_IAMR                64
2415   PPC     KVM_REG_PPC_TFHAR               64     2415   PPC     KVM_REG_PPC_TFHAR               64
2416   PPC     KVM_REG_PPC_TFIAR               64     2416   PPC     KVM_REG_PPC_TFIAR               64
2417   PPC     KVM_REG_PPC_TEXASR              64     2417   PPC     KVM_REG_PPC_TEXASR              64
2418   PPC     KVM_REG_PPC_FSCR                64     2418   PPC     KVM_REG_PPC_FSCR                64
2419   PPC     KVM_REG_PPC_PSPB                32     2419   PPC     KVM_REG_PPC_PSPB                32
2420   PPC     KVM_REG_PPC_EBBHR               64     2420   PPC     KVM_REG_PPC_EBBHR               64
2421   PPC     KVM_REG_PPC_EBBRR               64     2421   PPC     KVM_REG_PPC_EBBRR               64
2422   PPC     KVM_REG_PPC_BESCR               64     2422   PPC     KVM_REG_PPC_BESCR               64
2423   PPC     KVM_REG_PPC_TAR                 64     2423   PPC     KVM_REG_PPC_TAR                 64
2424   PPC     KVM_REG_PPC_DPDES               64     2424   PPC     KVM_REG_PPC_DPDES               64
2425   PPC     KVM_REG_PPC_DAWR                64     2425   PPC     KVM_REG_PPC_DAWR                64
2426   PPC     KVM_REG_PPC_DAWRX               64     2426   PPC     KVM_REG_PPC_DAWRX               64
2427   PPC     KVM_REG_PPC_CIABR               64     2427   PPC     KVM_REG_PPC_CIABR               64
2428   PPC     KVM_REG_PPC_IC                  64     2428   PPC     KVM_REG_PPC_IC                  64
2429   PPC     KVM_REG_PPC_VTB                 64     2429   PPC     KVM_REG_PPC_VTB                 64
2430   PPC     KVM_REG_PPC_CSIGR               64     2430   PPC     KVM_REG_PPC_CSIGR               64
2431   PPC     KVM_REG_PPC_TACR                64     2431   PPC     KVM_REG_PPC_TACR                64
2432   PPC     KVM_REG_PPC_TCSCR               64     2432   PPC     KVM_REG_PPC_TCSCR               64
2433   PPC     KVM_REG_PPC_PID                 64     2433   PPC     KVM_REG_PPC_PID                 64
2434   PPC     KVM_REG_PPC_ACOP                64     2434   PPC     KVM_REG_PPC_ACOP                64
2435   PPC     KVM_REG_PPC_VRSAVE              32     2435   PPC     KVM_REG_PPC_VRSAVE              32
2436   PPC     KVM_REG_PPC_LPCR                32     2436   PPC     KVM_REG_PPC_LPCR                32
2437   PPC     KVM_REG_PPC_LPCR_64             64     2437   PPC     KVM_REG_PPC_LPCR_64             64
2438   PPC     KVM_REG_PPC_PPR                 64     2438   PPC     KVM_REG_PPC_PPR                 64
2439   PPC     KVM_REG_PPC_ARCH_COMPAT         32     2439   PPC     KVM_REG_PPC_ARCH_COMPAT         32
2440   PPC     KVM_REG_PPC_DABRX               32     2440   PPC     KVM_REG_PPC_DABRX               32
2441   PPC     KVM_REG_PPC_WORT                64     2441   PPC     KVM_REG_PPC_WORT                64
2442   PPC     KVM_REG_PPC_SPRG9               64     2442   PPC     KVM_REG_PPC_SPRG9               64
2443   PPC     KVM_REG_PPC_DBSR                32     2443   PPC     KVM_REG_PPC_DBSR                32
2444   PPC     KVM_REG_PPC_TIDR                64     2444   PPC     KVM_REG_PPC_TIDR                64
2445   PPC     KVM_REG_PPC_PSSCR               64     2445   PPC     KVM_REG_PPC_PSSCR               64
2446   PPC     KVM_REG_PPC_DEC_EXPIRY          64     2446   PPC     KVM_REG_PPC_DEC_EXPIRY          64
2447   PPC     KVM_REG_PPC_PTCR                64     2447   PPC     KVM_REG_PPC_PTCR                64
2448   PPC     KVM_REG_PPC_HASHKEYR            64     2448   PPC     KVM_REG_PPC_HASHKEYR            64
2449   PPC     KVM_REG_PPC_HASHPKEYR           64     2449   PPC     KVM_REG_PPC_HASHPKEYR           64
2450   PPC     KVM_REG_PPC_DAWR1               64     2450   PPC     KVM_REG_PPC_DAWR1               64
2451   PPC     KVM_REG_PPC_DAWRX1              64     2451   PPC     KVM_REG_PPC_DAWRX1              64
2452   PPC     KVM_REG_PPC_DEXCR               64     2452   PPC     KVM_REG_PPC_DEXCR               64
2453   PPC     KVM_REG_PPC_TM_GPR0             64     2453   PPC     KVM_REG_PPC_TM_GPR0             64
2454   ...                                            2454   ...
2455   PPC     KVM_REG_PPC_TM_GPR31            64     2455   PPC     KVM_REG_PPC_TM_GPR31            64
2456   PPC     KVM_REG_PPC_TM_VSR0             128    2456   PPC     KVM_REG_PPC_TM_VSR0             128
2457   ...                                            2457   ...
2458   PPC     KVM_REG_PPC_TM_VSR63            128    2458   PPC     KVM_REG_PPC_TM_VSR63            128
2459   PPC     KVM_REG_PPC_TM_CR               64     2459   PPC     KVM_REG_PPC_TM_CR               64
2460   PPC     KVM_REG_PPC_TM_LR               64     2460   PPC     KVM_REG_PPC_TM_LR               64
2461   PPC     KVM_REG_PPC_TM_CTR              64     2461   PPC     KVM_REG_PPC_TM_CTR              64
2462   PPC     KVM_REG_PPC_TM_FPSCR            64     2462   PPC     KVM_REG_PPC_TM_FPSCR            64
2463   PPC     KVM_REG_PPC_TM_AMR              64     2463   PPC     KVM_REG_PPC_TM_AMR              64
2464   PPC     KVM_REG_PPC_TM_PPR              64     2464   PPC     KVM_REG_PPC_TM_PPR              64
2465   PPC     KVM_REG_PPC_TM_VRSAVE           64     2465   PPC     KVM_REG_PPC_TM_VRSAVE           64
2466   PPC     KVM_REG_PPC_TM_VSCR             32     2466   PPC     KVM_REG_PPC_TM_VSCR             32
2467   PPC     KVM_REG_PPC_TM_DSCR             64     2467   PPC     KVM_REG_PPC_TM_DSCR             64
2468   PPC     KVM_REG_PPC_TM_TAR              64     2468   PPC     KVM_REG_PPC_TM_TAR              64
2469   PPC     KVM_REG_PPC_TM_XER              64     2469   PPC     KVM_REG_PPC_TM_XER              64
2470                                                  2470 
2471   MIPS    KVM_REG_MIPS_R0                 64     2471   MIPS    KVM_REG_MIPS_R0                 64
2472   ...                                            2472   ...
2473   MIPS    KVM_REG_MIPS_R31                64     2473   MIPS    KVM_REG_MIPS_R31                64
2474   MIPS    KVM_REG_MIPS_HI                 64     2474   MIPS    KVM_REG_MIPS_HI                 64
2475   MIPS    KVM_REG_MIPS_LO                 64     2475   MIPS    KVM_REG_MIPS_LO                 64
2476   MIPS    KVM_REG_MIPS_PC                 64     2476   MIPS    KVM_REG_MIPS_PC                 64
2477   MIPS    KVM_REG_MIPS_CP0_INDEX          32     2477   MIPS    KVM_REG_MIPS_CP0_INDEX          32
2478   MIPS    KVM_REG_MIPS_CP0_ENTRYLO0       64     2478   MIPS    KVM_REG_MIPS_CP0_ENTRYLO0       64
2479   MIPS    KVM_REG_MIPS_CP0_ENTRYLO1       64     2479   MIPS    KVM_REG_MIPS_CP0_ENTRYLO1       64
2480   MIPS    KVM_REG_MIPS_CP0_CONTEXT        64     2480   MIPS    KVM_REG_MIPS_CP0_CONTEXT        64
2481   MIPS    KVM_REG_MIPS_CP0_CONTEXTCONFIG  32     2481   MIPS    KVM_REG_MIPS_CP0_CONTEXTCONFIG  32
2482   MIPS    KVM_REG_MIPS_CP0_USERLOCAL      64     2482   MIPS    KVM_REG_MIPS_CP0_USERLOCAL      64
2483   MIPS    KVM_REG_MIPS_CP0_XCONTEXTCONFIG 64     2483   MIPS    KVM_REG_MIPS_CP0_XCONTEXTCONFIG 64
2484   MIPS    KVM_REG_MIPS_CP0_PAGEMASK       32     2484   MIPS    KVM_REG_MIPS_CP0_PAGEMASK       32
2485   MIPS    KVM_REG_MIPS_CP0_PAGEGRAIN      32     2485   MIPS    KVM_REG_MIPS_CP0_PAGEGRAIN      32
2486   MIPS    KVM_REG_MIPS_CP0_SEGCTL0        64     2486   MIPS    KVM_REG_MIPS_CP0_SEGCTL0        64
2487   MIPS    KVM_REG_MIPS_CP0_SEGCTL1        64     2487   MIPS    KVM_REG_MIPS_CP0_SEGCTL1        64
2488   MIPS    KVM_REG_MIPS_CP0_SEGCTL2        64     2488   MIPS    KVM_REG_MIPS_CP0_SEGCTL2        64
2489   MIPS    KVM_REG_MIPS_CP0_PWBASE         64     2489   MIPS    KVM_REG_MIPS_CP0_PWBASE         64
2490   MIPS    KVM_REG_MIPS_CP0_PWFIELD        64     2490   MIPS    KVM_REG_MIPS_CP0_PWFIELD        64
2491   MIPS    KVM_REG_MIPS_CP0_PWSIZE         64     2491   MIPS    KVM_REG_MIPS_CP0_PWSIZE         64
2492   MIPS    KVM_REG_MIPS_CP0_WIRED          32     2492   MIPS    KVM_REG_MIPS_CP0_WIRED          32
2493   MIPS    KVM_REG_MIPS_CP0_PWCTL          32     2493   MIPS    KVM_REG_MIPS_CP0_PWCTL          32
2494   MIPS    KVM_REG_MIPS_CP0_HWRENA         32     2494   MIPS    KVM_REG_MIPS_CP0_HWRENA         32
2495   MIPS    KVM_REG_MIPS_CP0_BADVADDR       64     2495   MIPS    KVM_REG_MIPS_CP0_BADVADDR       64
2496   MIPS    KVM_REG_MIPS_CP0_BADINSTR       32     2496   MIPS    KVM_REG_MIPS_CP0_BADINSTR       32
2497   MIPS    KVM_REG_MIPS_CP0_BADINSTRP      32     2497   MIPS    KVM_REG_MIPS_CP0_BADINSTRP      32
2498   MIPS    KVM_REG_MIPS_CP0_COUNT          32     2498   MIPS    KVM_REG_MIPS_CP0_COUNT          32
2499   MIPS    KVM_REG_MIPS_CP0_ENTRYHI        64     2499   MIPS    KVM_REG_MIPS_CP0_ENTRYHI        64
2500   MIPS    KVM_REG_MIPS_CP0_COMPARE        32     2500   MIPS    KVM_REG_MIPS_CP0_COMPARE        32
2501   MIPS    KVM_REG_MIPS_CP0_STATUS         32     2501   MIPS    KVM_REG_MIPS_CP0_STATUS         32
2502   MIPS    KVM_REG_MIPS_CP0_INTCTL         32     2502   MIPS    KVM_REG_MIPS_CP0_INTCTL         32
2503   MIPS    KVM_REG_MIPS_CP0_CAUSE          32     2503   MIPS    KVM_REG_MIPS_CP0_CAUSE          32
2504   MIPS    KVM_REG_MIPS_CP0_EPC            64     2504   MIPS    KVM_REG_MIPS_CP0_EPC            64
2505   MIPS    KVM_REG_MIPS_CP0_PRID           32     2505   MIPS    KVM_REG_MIPS_CP0_PRID           32
2506   MIPS    KVM_REG_MIPS_CP0_EBASE          64     2506   MIPS    KVM_REG_MIPS_CP0_EBASE          64
2507   MIPS    KVM_REG_MIPS_CP0_CONFIG         32     2507   MIPS    KVM_REG_MIPS_CP0_CONFIG         32
2508   MIPS    KVM_REG_MIPS_CP0_CONFIG1        32     2508   MIPS    KVM_REG_MIPS_CP0_CONFIG1        32
2509   MIPS    KVM_REG_MIPS_CP0_CONFIG2        32     2509   MIPS    KVM_REG_MIPS_CP0_CONFIG2        32
2510   MIPS    KVM_REG_MIPS_CP0_CONFIG3        32     2510   MIPS    KVM_REG_MIPS_CP0_CONFIG3        32
2511   MIPS    KVM_REG_MIPS_CP0_CONFIG4        32     2511   MIPS    KVM_REG_MIPS_CP0_CONFIG4        32
2512   MIPS    KVM_REG_MIPS_CP0_CONFIG5        32     2512   MIPS    KVM_REG_MIPS_CP0_CONFIG5        32
2513   MIPS    KVM_REG_MIPS_CP0_CONFIG7        32     2513   MIPS    KVM_REG_MIPS_CP0_CONFIG7        32
2514   MIPS    KVM_REG_MIPS_CP0_XCONTEXT       64     2514   MIPS    KVM_REG_MIPS_CP0_XCONTEXT       64
2515   MIPS    KVM_REG_MIPS_CP0_ERROREPC       64     2515   MIPS    KVM_REG_MIPS_CP0_ERROREPC       64
2516   MIPS    KVM_REG_MIPS_CP0_KSCRATCH1      64     2516   MIPS    KVM_REG_MIPS_CP0_KSCRATCH1      64
2517   MIPS    KVM_REG_MIPS_CP0_KSCRATCH2      64     2517   MIPS    KVM_REG_MIPS_CP0_KSCRATCH2      64
2518   MIPS    KVM_REG_MIPS_CP0_KSCRATCH3      64     2518   MIPS    KVM_REG_MIPS_CP0_KSCRATCH3      64
2519   MIPS    KVM_REG_MIPS_CP0_KSCRATCH4      64     2519   MIPS    KVM_REG_MIPS_CP0_KSCRATCH4      64
2520   MIPS    KVM_REG_MIPS_CP0_KSCRATCH5      64     2520   MIPS    KVM_REG_MIPS_CP0_KSCRATCH5      64
2521   MIPS    KVM_REG_MIPS_CP0_KSCRATCH6      64     2521   MIPS    KVM_REG_MIPS_CP0_KSCRATCH6      64
2522   MIPS    KVM_REG_MIPS_CP0_MAAR(0..63)    64     2522   MIPS    KVM_REG_MIPS_CP0_MAAR(0..63)    64
2523   MIPS    KVM_REG_MIPS_COUNT_CTL          64     2523   MIPS    KVM_REG_MIPS_COUNT_CTL          64
2524   MIPS    KVM_REG_MIPS_COUNT_RESUME       64     2524   MIPS    KVM_REG_MIPS_COUNT_RESUME       64
2525   MIPS    KVM_REG_MIPS_COUNT_HZ           64     2525   MIPS    KVM_REG_MIPS_COUNT_HZ           64
2526   MIPS    KVM_REG_MIPS_FPR_32(0..31)      32     2526   MIPS    KVM_REG_MIPS_FPR_32(0..31)      32
2527   MIPS    KVM_REG_MIPS_FPR_64(0..31)      64     2527   MIPS    KVM_REG_MIPS_FPR_64(0..31)      64
2528   MIPS    KVM_REG_MIPS_VEC_128(0..31)     128    2528   MIPS    KVM_REG_MIPS_VEC_128(0..31)     128
2529   MIPS    KVM_REG_MIPS_FCR_IR             32     2529   MIPS    KVM_REG_MIPS_FCR_IR             32
2530   MIPS    KVM_REG_MIPS_FCR_CSR            32     2530   MIPS    KVM_REG_MIPS_FCR_CSR            32
2531   MIPS    KVM_REG_MIPS_MSA_IR             32     2531   MIPS    KVM_REG_MIPS_MSA_IR             32
2532   MIPS    KVM_REG_MIPS_MSA_CSR            32     2532   MIPS    KVM_REG_MIPS_MSA_CSR            32
2533   ======= =============================== ===    2533   ======= =============================== ============
2534                                                  2534 
2535 ARM registers are mapped using the lower 32 b    2535 ARM registers are mapped using the lower 32 bits.  The upper 16 of that
2536 is the register group type, or coprocessor nu    2536 is the register group type, or coprocessor number:
2537                                                  2537 
2538 ARM core registers have the following id bit     2538 ARM core registers have the following id bit patterns::
2539                                                  2539 
2540   0x4020 0000 0010 <index into the kvm_regs s    2540   0x4020 0000 0010 <index into the kvm_regs struct:16>
2541                                                  2541 
2542 ARM 32-bit CP15 registers have the following     2542 ARM 32-bit CP15 registers have the following id bit patterns::
2543                                                  2543 
2544   0x4020 0000 000F <zero:1> <crn:4> <crm:4> <    2544   0x4020 0000 000F <zero:1> <crn:4> <crm:4> <opc1:4> <opc2:3>
2545                                                  2545 
2546 ARM 64-bit CP15 registers have the following     2546 ARM 64-bit CP15 registers have the following id bit patterns::
2547                                                  2547 
2548   0x4030 0000 000F <zero:1> <zero:4> <crm:4>     2548   0x4030 0000 000F <zero:1> <zero:4> <crm:4> <opc1:4> <zero:3>
2549                                                  2549 
2550 ARM CCSIDR registers are demultiplexed by CSS    2550 ARM CCSIDR registers are demultiplexed by CSSELR value::
2551                                                  2551 
2552   0x4020 0000 0011 00 <csselr:8>                 2552   0x4020 0000 0011 00 <csselr:8>
2553                                                  2553 
2554 ARM 32-bit VFP control registers have the fol    2554 ARM 32-bit VFP control registers have the following id bit patterns::
2555                                                  2555 
2556   0x4020 0000 0012 1 <regno:12>                  2556   0x4020 0000 0012 1 <regno:12>
2557                                                  2557 
2558 ARM 64-bit FP registers have the following id    2558 ARM 64-bit FP registers have the following id bit patterns::
2559                                                  2559 
2560   0x4030 0000 0012 0 <regno:12>                  2560   0x4030 0000 0012 0 <regno:12>
2561                                                  2561 
2562 ARM firmware pseudo-registers have the follow    2562 ARM firmware pseudo-registers have the following bit pattern::
2563                                                  2563 
2564   0x4030 0000 0014 <regno:16>                    2564   0x4030 0000 0014 <regno:16>
2565                                                  2565 
2566                                                  2566 
2567 arm64 registers are mapped using the lower 32    2567 arm64 registers are mapped using the lower 32 bits. The upper 16 of
2568 that is the register group type, or coprocess    2568 that is the register group type, or coprocessor number:
2569                                                  2569 
2570 arm64 core/FP-SIMD registers have the followi    2570 arm64 core/FP-SIMD registers have the following id bit patterns. Note
2571 that the size of the access is variable, as t    2571 that the size of the access is variable, as the kvm_regs structure
2572 contains elements ranging from 32 to 128 bits    2572 contains elements ranging from 32 to 128 bits. The index is a 32bit
2573 value in the kvm_regs structure seen as a 32b    2573 value in the kvm_regs structure seen as a 32bit array::
2574                                                  2574 
2575   0x60x0 0000 0010 <index into the kvm_regs s    2575   0x60x0 0000 0010 <index into the kvm_regs struct:16>
2576                                                  2576 
2577 Specifically:                                    2577 Specifically:
2578                                                  2578 
2579 ======================= ========= ===== =====    2579 ======================= ========= ===== =======================================
2580     Encoding            Register  Bits  kvm_r    2580     Encoding            Register  Bits  kvm_regs member
2581 ======================= ========= ===== =====    2581 ======================= ========= ===== =======================================
2582   0x6030 0000 0010 0000 X0          64  regs.    2582   0x6030 0000 0010 0000 X0          64  regs.regs[0]
2583   0x6030 0000 0010 0002 X1          64  regs.    2583   0x6030 0000 0010 0002 X1          64  regs.regs[1]
2584   ...                                            2584   ...
2585   0x6030 0000 0010 003c X30         64  regs.    2585   0x6030 0000 0010 003c X30         64  regs.regs[30]
2586   0x6030 0000 0010 003e SP          64  regs.    2586   0x6030 0000 0010 003e SP          64  regs.sp
2587   0x6030 0000 0010 0040 PC          64  regs.    2587   0x6030 0000 0010 0040 PC          64  regs.pc
2588   0x6030 0000 0010 0042 PSTATE      64  regs.    2588   0x6030 0000 0010 0042 PSTATE      64  regs.pstate
2589   0x6030 0000 0010 0044 SP_EL1      64  sp_el    2589   0x6030 0000 0010 0044 SP_EL1      64  sp_el1
2590   0x6030 0000 0010 0046 ELR_EL1     64  elr_e    2590   0x6030 0000 0010 0046 ELR_EL1     64  elr_el1
2591   0x6030 0000 0010 0048 SPSR_EL1    64  spsr[    2591   0x6030 0000 0010 0048 SPSR_EL1    64  spsr[KVM_SPSR_EL1] (alias SPSR_SVC)
2592   0x6030 0000 0010 004a SPSR_ABT    64  spsr[    2592   0x6030 0000 0010 004a SPSR_ABT    64  spsr[KVM_SPSR_ABT]
2593   0x6030 0000 0010 004c SPSR_UND    64  spsr[    2593   0x6030 0000 0010 004c SPSR_UND    64  spsr[KVM_SPSR_UND]
2594   0x6030 0000 0010 004e SPSR_IRQ    64  spsr[    2594   0x6030 0000 0010 004e SPSR_IRQ    64  spsr[KVM_SPSR_IRQ]
2595   0x6030 0000 0010 0050 SPSR_FIQ    64  spsr[    2595   0x6030 0000 0010 0050 SPSR_FIQ    64  spsr[KVM_SPSR_FIQ]
2596   0x6040 0000 0010 0054 V0         128  fp_re    2596   0x6040 0000 0010 0054 V0         128  fp_regs.vregs[0]    [1]_
2597   0x6040 0000 0010 0058 V1         128  fp_re    2597   0x6040 0000 0010 0058 V1         128  fp_regs.vregs[1]    [1]_
2598   ...                                            2598   ...
2599   0x6040 0000 0010 00d0 V31        128  fp_re    2599   0x6040 0000 0010 00d0 V31        128  fp_regs.vregs[31]   [1]_
2600   0x6020 0000 0010 00d4 FPSR        32  fp_re    2600   0x6020 0000 0010 00d4 FPSR        32  fp_regs.fpsr
2601   0x6020 0000 0010 00d5 FPCR        32  fp_re    2601   0x6020 0000 0010 00d5 FPCR        32  fp_regs.fpcr
2602 ======================= ========= ===== =====    2602 ======================= ========= ===== =======================================
2603                                                  2603 
2604 .. [1] These encodings are not accepted for S    2604 .. [1] These encodings are not accepted for SVE-enabled vcpus.  See
2605        KVM_ARM_VCPU_INIT.                        2605        KVM_ARM_VCPU_INIT.
2606                                                  2606 
2607        The equivalent register content can be    2607        The equivalent register content can be accessed via bits [127:0] of
2608        the corresponding SVE Zn registers ins    2608        the corresponding SVE Zn registers instead for vcpus that have SVE
2609        enabled (see below).                      2609        enabled (see below).
2610                                                  2610 
2611 arm64 CCSIDR registers are demultiplexed by C    2611 arm64 CCSIDR registers are demultiplexed by CSSELR value::
2612                                                  2612 
2613   0x6020 0000 0011 00 <csselr:8>                 2613   0x6020 0000 0011 00 <csselr:8>
2614                                                  2614 
2615 arm64 system registers have the following id     2615 arm64 system registers have the following id bit patterns::
2616                                                  2616 
2617   0x6030 0000 0013 <op0:2> <op1:3> <crn:4> <c    2617   0x6030 0000 0013 <op0:2> <op1:3> <crn:4> <crm:4> <op2:3>
2618                                                  2618 
2619 .. warning::                                     2619 .. warning::
2620                                                  2620 
2621      Two system register IDs do not follow th    2621      Two system register IDs do not follow the specified pattern.  These
2622      are KVM_REG_ARM_TIMER_CVAL and KVM_REG_A    2622      are KVM_REG_ARM_TIMER_CVAL and KVM_REG_ARM_TIMER_CNT, which map to
2623      system registers CNTV_CVAL_EL0 and CNTVC    2623      system registers CNTV_CVAL_EL0 and CNTVCT_EL0 respectively.  These
2624      two had their values accidentally swappe    2624      two had their values accidentally swapped, which means TIMER_CVAL is
2625      derived from the register encoding for C    2625      derived from the register encoding for CNTVCT_EL0 and TIMER_CNT is
2626      derived from the register encoding for C    2626      derived from the register encoding for CNTV_CVAL_EL0.  As this is
2627      API, it must remain this way.               2627      API, it must remain this way.
2628                                                  2628 
2629 arm64 firmware pseudo-registers have the foll    2629 arm64 firmware pseudo-registers have the following bit pattern::
2630                                                  2630 
2631   0x6030 0000 0014 <regno:16>                    2631   0x6030 0000 0014 <regno:16>
2632                                                  2632 
2633 arm64 SVE registers have the following bit pa    2633 arm64 SVE registers have the following bit patterns::
2634                                                  2634 
2635   0x6080 0000 0015 00 <n:5> <slice:5>   Zn bi    2635   0x6080 0000 0015 00 <n:5> <slice:5>   Zn bits[2048*slice + 2047 : 2048*slice]
2636   0x6050 0000 0015 04 <n:4> <slice:5>   Pn bi    2636   0x6050 0000 0015 04 <n:4> <slice:5>   Pn bits[256*slice + 255 : 256*slice]
2637   0x6050 0000 0015 060 <slice:5>        FFR b    2637   0x6050 0000 0015 060 <slice:5>        FFR bits[256*slice + 255 : 256*slice]
2638   0x6060 0000 0015 ffff                 KVM_R    2638   0x6060 0000 0015 ffff                 KVM_REG_ARM64_SVE_VLS pseudo-register
2639                                                  2639 
2640 Access to register IDs where 2048 * slice >=     2640 Access to register IDs where 2048 * slice >= 128 * max_vq will fail with
2641 ENOENT.  max_vq is the vcpu's maximum support    2641 ENOENT.  max_vq is the vcpu's maximum supported vector length in 128-bit
2642 quadwords: see [2]_ below.                       2642 quadwords: see [2]_ below.
2643                                                  2643 
2644 These registers are only accessible on vcpus     2644 These registers are only accessible on vcpus for which SVE is enabled.
2645 See KVM_ARM_VCPU_INIT for details.               2645 See KVM_ARM_VCPU_INIT for details.
2646                                                  2646 
2647 In addition, except for KVM_REG_ARM64_SVE_VLS    2647 In addition, except for KVM_REG_ARM64_SVE_VLS, these registers are not
2648 accessible until the vcpu's SVE configuration    2648 accessible until the vcpu's SVE configuration has been finalized
2649 using KVM_ARM_VCPU_FINALIZE(KVM_ARM_VCPU_SVE)    2649 using KVM_ARM_VCPU_FINALIZE(KVM_ARM_VCPU_SVE).  See KVM_ARM_VCPU_INIT
2650 and KVM_ARM_VCPU_FINALIZE for more informatio    2650 and KVM_ARM_VCPU_FINALIZE for more information about this procedure.
2651                                                  2651 
2652 KVM_REG_ARM64_SVE_VLS is a pseudo-register th    2652 KVM_REG_ARM64_SVE_VLS is a pseudo-register that allows the set of vector
2653 lengths supported by the vcpu to be discovere    2653 lengths supported by the vcpu to be discovered and configured by
2654 userspace.  When transferred to or from user     2654 userspace.  When transferred to or from user memory via KVM_GET_ONE_REG
2655 or KVM_SET_ONE_REG, the value of this registe    2655 or KVM_SET_ONE_REG, the value of this register is of type
2656 __u64[KVM_ARM64_SVE_VLS_WORDS], and encodes t    2656 __u64[KVM_ARM64_SVE_VLS_WORDS], and encodes the set of vector lengths as
2657 follows::                                        2657 follows::
2658                                                  2658 
2659   __u64 vector_lengths[KVM_ARM64_SVE_VLS_WORD    2659   __u64 vector_lengths[KVM_ARM64_SVE_VLS_WORDS];
2660                                                  2660 
2661   if (vq >= SVE_VQ_MIN && vq <= SVE_VQ_MAX &&    2661   if (vq >= SVE_VQ_MIN && vq <= SVE_VQ_MAX &&
2662       ((vector_lengths[(vq - KVM_ARM64_SVE_VQ    2662       ((vector_lengths[(vq - KVM_ARM64_SVE_VQ_MIN) / 64] >>
2663                 ((vq - KVM_ARM64_SVE_VQ_MIN)     2663                 ((vq - KVM_ARM64_SVE_VQ_MIN) % 64)) & 1))
2664         /* Vector length vq * 16 bytes suppor    2664         /* Vector length vq * 16 bytes supported */
2665   else                                           2665   else
2666         /* Vector length vq * 16 bytes not su    2666         /* Vector length vq * 16 bytes not supported */
2667                                                  2667 
2668 .. [2] The maximum value vq for which the abo    2668 .. [2] The maximum value vq for which the above condition is true is
2669        max_vq.  This is the maximum vector le    2669        max_vq.  This is the maximum vector length available to the guest on
2670        this vcpu, and determines which regist    2670        this vcpu, and determines which register slices are visible through
2671        this ioctl interface.                     2671        this ioctl interface.
2672                                                  2672 
2673 (See Documentation/arch/arm64/sve.rst for an     2673 (See Documentation/arch/arm64/sve.rst for an explanation of the "vq"
2674 nomenclature.)                                   2674 nomenclature.)
2675                                                  2675 
2676 KVM_REG_ARM64_SVE_VLS is only accessible afte    2676 KVM_REG_ARM64_SVE_VLS is only accessible after KVM_ARM_VCPU_INIT.
2677 KVM_ARM_VCPU_INIT initialises it to the best     2677 KVM_ARM_VCPU_INIT initialises it to the best set of vector lengths that
2678 the host supports.                               2678 the host supports.
2679                                                  2679 
2680 Userspace may subsequently modify it if desir    2680 Userspace may subsequently modify it if desired until the vcpu's SVE
2681 configuration is finalized using KVM_ARM_VCPU    2681 configuration is finalized using KVM_ARM_VCPU_FINALIZE(KVM_ARM_VCPU_SVE).
2682                                                  2682 
2683 Apart from simply removing all vector lengths    2683 Apart from simply removing all vector lengths from the host set that
2684 exceed some value, support for arbitrarily ch    2684 exceed some value, support for arbitrarily chosen sets of vector lengths
2685 is hardware-dependent and may not be availabl    2685 is hardware-dependent and may not be available.  Attempting to configure
2686 an invalid set of vector lengths via KVM_SET_    2686 an invalid set of vector lengths via KVM_SET_ONE_REG will fail with
2687 EINVAL.                                          2687 EINVAL.
2688                                                  2688 
2689 After the vcpu's SVE configuration is finaliz    2689 After the vcpu's SVE configuration is finalized, further attempts to
2690 write this register will fail with EPERM.        2690 write this register will fail with EPERM.
2691                                                  2691 
2692 arm64 bitmap feature firmware pseudo-register    2692 arm64 bitmap feature firmware pseudo-registers have the following bit pattern::
2693                                                  2693 
2694   0x6030 0000 0016 <regno:16>                    2694   0x6030 0000 0016 <regno:16>
2695                                                  2695 
2696 The bitmap feature firmware registers exposes    2696 The bitmap feature firmware registers exposes the hypercall services that
2697 are available for userspace to configure. The    2697 are available for userspace to configure. The set bits corresponds to the
2698 services that are available for the guests to    2698 services that are available for the guests to access. By default, KVM
2699 sets all the supported bits during VM initial    2699 sets all the supported bits during VM initialization. The userspace can
2700 discover the available services via KVM_GET_O    2700 discover the available services via KVM_GET_ONE_REG, and write back the
2701 bitmap corresponding to the features that it     2701 bitmap corresponding to the features that it wishes guests to see via
2702 KVM_SET_ONE_REG.                                 2702 KVM_SET_ONE_REG.
2703                                                  2703 
2704 Note: These registers are immutable once any     2704 Note: These registers are immutable once any of the vCPUs of the VM has
2705 run at least once. A KVM_SET_ONE_REG in such     2705 run at least once. A KVM_SET_ONE_REG in such a scenario will return
2706 a -EBUSY to userspace.                           2706 a -EBUSY to userspace.
2707                                                  2707 
2708 (See Documentation/virt/kvm/arm/hypercalls.rs    2708 (See Documentation/virt/kvm/arm/hypercalls.rst for more details.)
2709                                                  2709 
2710                                                  2710 
2711 MIPS registers are mapped using the lower 32     2711 MIPS registers are mapped using the lower 32 bits.  The upper 16 of that is
2712 the register group type:                         2712 the register group type:
2713                                                  2713 
2714 MIPS core registers (see above) have the foll    2714 MIPS core registers (see above) have the following id bit patterns::
2715                                                  2715 
2716   0x7030 0000 0000 <reg:16>                      2716   0x7030 0000 0000 <reg:16>
2717                                                  2717 
2718 MIPS CP0 registers (see KVM_REG_MIPS_CP0_* ab    2718 MIPS CP0 registers (see KVM_REG_MIPS_CP0_* above) have the following id bit
2719 patterns depending on whether they're 32-bit     2719 patterns depending on whether they're 32-bit or 64-bit registers::
2720                                                  2720 
2721   0x7020 0000 0001 00 <reg:5> <sel:3>   (32-b    2721   0x7020 0000 0001 00 <reg:5> <sel:3>   (32-bit)
2722   0x7030 0000 0001 00 <reg:5> <sel:3>   (64-b    2722   0x7030 0000 0001 00 <reg:5> <sel:3>   (64-bit)
2723                                                  2723 
2724 Note: KVM_REG_MIPS_CP0_ENTRYLO0 and KVM_REG_M    2724 Note: KVM_REG_MIPS_CP0_ENTRYLO0 and KVM_REG_MIPS_CP0_ENTRYLO1 are the MIPS64
2725 versions of the EntryLo registers regardless     2725 versions of the EntryLo registers regardless of the word size of the host
2726 hardware, host kernel, guest, and whether XPA    2726 hardware, host kernel, guest, and whether XPA is present in the guest, i.e.
2727 with the RI and XI bits (if they exist) in bi    2727 with the RI and XI bits (if they exist) in bits 63 and 62 respectively, and
2728 the PFNX field starting at bit 30.               2728 the PFNX field starting at bit 30.
2729                                                  2729 
2730 MIPS MAARs (see KVM_REG_MIPS_CP0_MAAR(*) abov    2730 MIPS MAARs (see KVM_REG_MIPS_CP0_MAAR(*) above) have the following id bit
2731 patterns::                                       2731 patterns::
2732                                                  2732 
2733   0x7030 0000 0001 01 <reg:8>                    2733   0x7030 0000 0001 01 <reg:8>
2734                                                  2734 
2735 MIPS KVM control registers (see above) have t    2735 MIPS KVM control registers (see above) have the following id bit patterns::
2736                                                  2736 
2737   0x7030 0000 0002 <reg:16>                      2737   0x7030 0000 0002 <reg:16>
2738                                                  2738 
2739 MIPS FPU registers (see KVM_REG_MIPS_FPR_{32,    2739 MIPS FPU registers (see KVM_REG_MIPS_FPR_{32,64}() above) have the following
2740 id bit patterns depending on the size of the     2740 id bit patterns depending on the size of the register being accessed. They are
2741 always accessed according to the current gues    2741 always accessed according to the current guest FPU mode (Status.FR and
2742 Config5.FRE), i.e. as the guest would see the    2742 Config5.FRE), i.e. as the guest would see them, and they become unpredictable
2743 if the guest FPU mode is changed. MIPS SIMD A    2743 if the guest FPU mode is changed. MIPS SIMD Architecture (MSA) vector
2744 registers (see KVM_REG_MIPS_VEC_128() above)     2744 registers (see KVM_REG_MIPS_VEC_128() above) have similar patterns as they
2745 overlap the FPU registers::                      2745 overlap the FPU registers::
2746                                                  2746 
2747   0x7020 0000 0003 00 <0:3> <reg:5> (32-bit F    2747   0x7020 0000 0003 00 <0:3> <reg:5> (32-bit FPU registers)
2748   0x7030 0000 0003 00 <0:3> <reg:5> (64-bit F    2748   0x7030 0000 0003 00 <0:3> <reg:5> (64-bit FPU registers)
2749   0x7040 0000 0003 00 <0:3> <reg:5> (128-bit     2749   0x7040 0000 0003 00 <0:3> <reg:5> (128-bit MSA vector registers)
2750                                                  2750 
2751 MIPS FPU control registers (see KVM_REG_MIPS_    2751 MIPS FPU control registers (see KVM_REG_MIPS_FCR_{IR,CSR} above) have the
2752 following id bit patterns::                      2752 following id bit patterns::
2753                                                  2753 
2754   0x7020 0000 0003 01 <0:3> <reg:5>              2754   0x7020 0000 0003 01 <0:3> <reg:5>
2755                                                  2755 
2756 MIPS MSA control registers (see KVM_REG_MIPS_    2756 MIPS MSA control registers (see KVM_REG_MIPS_MSA_{IR,CSR} above) have the
2757 following id bit patterns::                      2757 following id bit patterns::
2758                                                  2758 
2759   0x7020 0000 0003 02 <0:3> <reg:5>              2759   0x7020 0000 0003 02 <0:3> <reg:5>
2760                                                  2760 
2761 RISC-V registers are mapped using the lower 3    2761 RISC-V registers are mapped using the lower 32 bits. The upper 8 bits of
2762 that is the register group type.                 2762 that is the register group type.
2763                                                  2763 
2764 RISC-V config registers are meant for configu    2764 RISC-V config registers are meant for configuring a Guest VCPU and it has
2765 the following id bit patterns::                  2765 the following id bit patterns::
2766                                                  2766 
2767   0x8020 0000 01 <index into the kvm_riscv_co    2767   0x8020 0000 01 <index into the kvm_riscv_config struct:24> (32bit Host)
2768   0x8030 0000 01 <index into the kvm_riscv_co    2768   0x8030 0000 01 <index into the kvm_riscv_config struct:24> (64bit Host)
2769                                                  2769 
2770 Following are the RISC-V config registers:       2770 Following are the RISC-V config registers:
2771                                                  2771 
2772 ======================= ========= ===========    2772 ======================= ========= =============================================
2773     Encoding            Register  Description    2773     Encoding            Register  Description
2774 ======================= ========= ===========    2774 ======================= ========= =============================================
2775   0x80x0 0000 0100 0000 isa       ISA feature    2775   0x80x0 0000 0100 0000 isa       ISA feature bitmap of Guest VCPU
2776 ======================= ========= ===========    2776 ======================= ========= =============================================
2777                                                  2777 
2778 The isa config register can be read anytime b    2778 The isa config register can be read anytime but can only be written before
2779 a Guest VCPU runs. It will have ISA feature b    2779 a Guest VCPU runs. It will have ISA feature bits matching underlying host
2780 set by default.                                  2780 set by default.
2781                                                  2781 
2782 RISC-V core registers represent the general e    2782 RISC-V core registers represent the general execution state of a Guest VCPU
2783 and it has the following id bit patterns::       2783 and it has the following id bit patterns::
2784                                                  2784 
2785   0x8020 0000 02 <index into the kvm_riscv_co    2785   0x8020 0000 02 <index into the kvm_riscv_core struct:24> (32bit Host)
2786   0x8030 0000 02 <index into the kvm_riscv_co    2786   0x8030 0000 02 <index into the kvm_riscv_core struct:24> (64bit Host)
2787                                                  2787 
2788 Following are the RISC-V core registers:         2788 Following are the RISC-V core registers:
2789                                                  2789 
2790 ======================= ========= ===========    2790 ======================= ========= =============================================
2791     Encoding            Register  Description    2791     Encoding            Register  Description
2792 ======================= ========= ===========    2792 ======================= ========= =============================================
2793   0x80x0 0000 0200 0000 regs.pc   Program cou    2793   0x80x0 0000 0200 0000 regs.pc   Program counter
2794   0x80x0 0000 0200 0001 regs.ra   Return addr    2794   0x80x0 0000 0200 0001 regs.ra   Return address
2795   0x80x0 0000 0200 0002 regs.sp   Stack point    2795   0x80x0 0000 0200 0002 regs.sp   Stack pointer
2796   0x80x0 0000 0200 0003 regs.gp   Global poin    2796   0x80x0 0000 0200 0003 regs.gp   Global pointer
2797   0x80x0 0000 0200 0004 regs.tp   Task pointe    2797   0x80x0 0000 0200 0004 regs.tp   Task pointer
2798   0x80x0 0000 0200 0005 regs.t0   Caller save    2798   0x80x0 0000 0200 0005 regs.t0   Caller saved register 0
2799   0x80x0 0000 0200 0006 regs.t1   Caller save    2799   0x80x0 0000 0200 0006 regs.t1   Caller saved register 1
2800   0x80x0 0000 0200 0007 regs.t2   Caller save    2800   0x80x0 0000 0200 0007 regs.t2   Caller saved register 2
2801   0x80x0 0000 0200 0008 regs.s0   Callee save    2801   0x80x0 0000 0200 0008 regs.s0   Callee saved register 0
2802   0x80x0 0000 0200 0009 regs.s1   Callee save    2802   0x80x0 0000 0200 0009 regs.s1   Callee saved register 1
2803   0x80x0 0000 0200 000a regs.a0   Function ar    2803   0x80x0 0000 0200 000a regs.a0   Function argument (or return value) 0
2804   0x80x0 0000 0200 000b regs.a1   Function ar    2804   0x80x0 0000 0200 000b regs.a1   Function argument (or return value) 1
2805   0x80x0 0000 0200 000c regs.a2   Function ar    2805   0x80x0 0000 0200 000c regs.a2   Function argument 2
2806   0x80x0 0000 0200 000d regs.a3   Function ar    2806   0x80x0 0000 0200 000d regs.a3   Function argument 3
2807   0x80x0 0000 0200 000e regs.a4   Function ar    2807   0x80x0 0000 0200 000e regs.a4   Function argument 4
2808   0x80x0 0000 0200 000f regs.a5   Function ar    2808   0x80x0 0000 0200 000f regs.a5   Function argument 5
2809   0x80x0 0000 0200 0010 regs.a6   Function ar    2809   0x80x0 0000 0200 0010 regs.a6   Function argument 6
2810   0x80x0 0000 0200 0011 regs.a7   Function ar    2810   0x80x0 0000 0200 0011 regs.a7   Function argument 7
2811   0x80x0 0000 0200 0012 regs.s2   Callee save    2811   0x80x0 0000 0200 0012 regs.s2   Callee saved register 2
2812   0x80x0 0000 0200 0013 regs.s3   Callee save    2812   0x80x0 0000 0200 0013 regs.s3   Callee saved register 3
2813   0x80x0 0000 0200 0014 regs.s4   Callee save    2813   0x80x0 0000 0200 0014 regs.s4   Callee saved register 4
2814   0x80x0 0000 0200 0015 regs.s5   Callee save    2814   0x80x0 0000 0200 0015 regs.s5   Callee saved register 5
2815   0x80x0 0000 0200 0016 regs.s6   Callee save    2815   0x80x0 0000 0200 0016 regs.s6   Callee saved register 6
2816   0x80x0 0000 0200 0017 regs.s7   Callee save    2816   0x80x0 0000 0200 0017 regs.s7   Callee saved register 7
2817   0x80x0 0000 0200 0018 regs.s8   Callee save    2817   0x80x0 0000 0200 0018 regs.s8   Callee saved register 8
2818   0x80x0 0000 0200 0019 regs.s9   Callee save    2818   0x80x0 0000 0200 0019 regs.s9   Callee saved register 9
2819   0x80x0 0000 0200 001a regs.s10  Callee save    2819   0x80x0 0000 0200 001a regs.s10  Callee saved register 10
2820   0x80x0 0000 0200 001b regs.s11  Callee save    2820   0x80x0 0000 0200 001b regs.s11  Callee saved register 11
2821   0x80x0 0000 0200 001c regs.t3   Caller save    2821   0x80x0 0000 0200 001c regs.t3   Caller saved register 3
2822   0x80x0 0000 0200 001d regs.t4   Caller save    2822   0x80x0 0000 0200 001d regs.t4   Caller saved register 4
2823   0x80x0 0000 0200 001e regs.t5   Caller save    2823   0x80x0 0000 0200 001e regs.t5   Caller saved register 5
2824   0x80x0 0000 0200 001f regs.t6   Caller save    2824   0x80x0 0000 0200 001f regs.t6   Caller saved register 6
2825   0x80x0 0000 0200 0020 mode      Privilege m    2825   0x80x0 0000 0200 0020 mode      Privilege mode (1 = S-mode or 0 = U-mode)
2826 ======================= ========= ===========    2826 ======================= ========= =============================================
2827                                                  2827 
2828 RISC-V csr registers represent the supervisor    2828 RISC-V csr registers represent the supervisor mode control/status registers
2829 of a Guest VCPU and it has the following id b    2829 of a Guest VCPU and it has the following id bit patterns::
2830                                                  2830 
2831   0x8020 0000 03 <index into the kvm_riscv_cs    2831   0x8020 0000 03 <index into the kvm_riscv_csr struct:24> (32bit Host)
2832   0x8030 0000 03 <index into the kvm_riscv_cs    2832   0x8030 0000 03 <index into the kvm_riscv_csr struct:24> (64bit Host)
2833                                                  2833 
2834 Following are the RISC-V csr registers:          2834 Following are the RISC-V csr registers:
2835                                                  2835 
2836 ======================= ========= ===========    2836 ======================= ========= =============================================
2837     Encoding            Register  Description    2837     Encoding            Register  Description
2838 ======================= ========= ===========    2838 ======================= ========= =============================================
2839   0x80x0 0000 0300 0000 sstatus   Supervisor     2839   0x80x0 0000 0300 0000 sstatus   Supervisor status
2840   0x80x0 0000 0300 0001 sie       Supervisor     2840   0x80x0 0000 0300 0001 sie       Supervisor interrupt enable
2841   0x80x0 0000 0300 0002 stvec     Supervisor     2841   0x80x0 0000 0300 0002 stvec     Supervisor trap vector base
2842   0x80x0 0000 0300 0003 sscratch  Supervisor     2842   0x80x0 0000 0300 0003 sscratch  Supervisor scratch register
2843   0x80x0 0000 0300 0004 sepc      Supervisor     2843   0x80x0 0000 0300 0004 sepc      Supervisor exception program counter
2844   0x80x0 0000 0300 0005 scause    Supervisor     2844   0x80x0 0000 0300 0005 scause    Supervisor trap cause
2845   0x80x0 0000 0300 0006 stval     Supervisor     2845   0x80x0 0000 0300 0006 stval     Supervisor bad address or instruction
2846   0x80x0 0000 0300 0007 sip       Supervisor     2846   0x80x0 0000 0300 0007 sip       Supervisor interrupt pending
2847   0x80x0 0000 0300 0008 satp      Supervisor     2847   0x80x0 0000 0300 0008 satp      Supervisor address translation and protection
2848 ======================= ========= ===========    2848 ======================= ========= =============================================
2849                                                  2849 
2850 RISC-V timer registers represent the timer st    2850 RISC-V timer registers represent the timer state of a Guest VCPU and it has
2851 the following id bit patterns::                  2851 the following id bit patterns::
2852                                                  2852 
2853   0x8030 0000 04 <index into the kvm_riscv_ti    2853   0x8030 0000 04 <index into the kvm_riscv_timer struct:24>
2854                                                  2854 
2855 Following are the RISC-V timer registers:        2855 Following are the RISC-V timer registers:
2856                                                  2856 
2857 ======================= ========= ===========    2857 ======================= ========= =============================================
2858     Encoding            Register  Description    2858     Encoding            Register  Description
2859 ======================= ========= ===========    2859 ======================= ========= =============================================
2860   0x8030 0000 0400 0000 frequency Time base f    2860   0x8030 0000 0400 0000 frequency Time base frequency (read-only)
2861   0x8030 0000 0400 0001 time      Time value     2861   0x8030 0000 0400 0001 time      Time value visible to Guest
2862   0x8030 0000 0400 0002 compare   Time compar    2862   0x8030 0000 0400 0002 compare   Time compare programmed by Guest
2863   0x8030 0000 0400 0003 state     Time compar    2863   0x8030 0000 0400 0003 state     Time compare state (1 = ON or 0 = OFF)
2864 ======================= ========= ===========    2864 ======================= ========= =============================================
2865                                                  2865 
2866 RISC-V F-extension registers represent the si    2866 RISC-V F-extension registers represent the single precision floating point
2867 state of a Guest VCPU and it has the followin    2867 state of a Guest VCPU and it has the following id bit patterns::
2868                                                  2868 
2869   0x8020 0000 05 <index into the __riscv_f_ex    2869   0x8020 0000 05 <index into the __riscv_f_ext_state struct:24>
2870                                                  2870 
2871 Following are the RISC-V F-extension register    2871 Following are the RISC-V F-extension registers:
2872                                                  2872 
2873 ======================= ========= ===========    2873 ======================= ========= =============================================
2874     Encoding            Register  Description    2874     Encoding            Register  Description
2875 ======================= ========= ===========    2875 ======================= ========= =============================================
2876   0x8020 0000 0500 0000 f[0]      Floating po    2876   0x8020 0000 0500 0000 f[0]      Floating point register 0
2877   ...                                            2877   ...
2878   0x8020 0000 0500 001f f[31]     Floating po    2878   0x8020 0000 0500 001f f[31]     Floating point register 31
2879   0x8020 0000 0500 0020 fcsr      Floating po    2879   0x8020 0000 0500 0020 fcsr      Floating point control and status register
2880 ======================= ========= ===========    2880 ======================= ========= =============================================
2881                                                  2881 
2882 RISC-V D-extension registers represent the do    2882 RISC-V D-extension registers represent the double precision floating point
2883 state of a Guest VCPU and it has the followin    2883 state of a Guest VCPU and it has the following id bit patterns::
2884                                                  2884 
2885   0x8020 0000 06 <index into the __riscv_d_ex    2885   0x8020 0000 06 <index into the __riscv_d_ext_state struct:24> (fcsr)
2886   0x8030 0000 06 <index into the __riscv_d_ex    2886   0x8030 0000 06 <index into the __riscv_d_ext_state struct:24> (non-fcsr)
2887                                                  2887 
2888 Following are the RISC-V D-extension register    2888 Following are the RISC-V D-extension registers:
2889                                                  2889 
2890 ======================= ========= ===========    2890 ======================= ========= =============================================
2891     Encoding            Register  Description    2891     Encoding            Register  Description
2892 ======================= ========= ===========    2892 ======================= ========= =============================================
2893   0x8030 0000 0600 0000 f[0]      Floating po    2893   0x8030 0000 0600 0000 f[0]      Floating point register 0
2894   ...                                            2894   ...
2895   0x8030 0000 0600 001f f[31]     Floating po    2895   0x8030 0000 0600 001f f[31]     Floating point register 31
2896   0x8020 0000 0600 0020 fcsr      Floating po    2896   0x8020 0000 0600 0020 fcsr      Floating point control and status register
2897 ======================= ========= ===========    2897 ======================= ========= =============================================
2898                                                  2898 
2899 LoongArch registers are mapped using the lowe    2899 LoongArch registers are mapped using the lower 32 bits. The upper 16 bits of
2900 that is the register group type.                 2900 that is the register group type.
2901                                                  2901 
2902 LoongArch csr registers are used to control g    2902 LoongArch csr registers are used to control guest cpu or get status of guest
2903 cpu, and they have the following id bit patte    2903 cpu, and they have the following id bit patterns::
2904                                                  2904 
2905   0x9030 0000 0001 00 <reg:5> <sel:3>   (64-b    2905   0x9030 0000 0001 00 <reg:5> <sel:3>   (64-bit)
2906                                                  2906 
2907 LoongArch KVM control registers are used to i    2907 LoongArch KVM control registers are used to implement some new defined functions
2908 such as set vcpu counter or reset vcpu, and t    2908 such as set vcpu counter or reset vcpu, and they have the following id bit patterns::
2909                                                  2909 
2910   0x9030 0000 0002 <reg:16>                      2910   0x9030 0000 0002 <reg:16>
2911                                                  2911 
2912                                                  2912 
2913 4.69 KVM_GET_ONE_REG                             2913 4.69 KVM_GET_ONE_REG
2914 --------------------                             2914 --------------------
2915                                                  2915 
2916 :Capability: KVM_CAP_ONE_REG                     2916 :Capability: KVM_CAP_ONE_REG
2917 :Architectures: all                              2917 :Architectures: all
2918 :Type: vcpu ioctl                                2918 :Type: vcpu ioctl
2919 :Parameters: struct kvm_one_reg (in and out)     2919 :Parameters: struct kvm_one_reg (in and out)
2920 :Returns: 0 on success, negative value on fai    2920 :Returns: 0 on success, negative value on failure
2921                                                  2921 
2922 Errors include:                                  2922 Errors include:
2923                                                  2923 
2924   ======== ==================================    2924   ======== ============================================================
2925   ENOENT   no such register                      2925   ENOENT   no such register
2926   EINVAL   invalid register ID, or no such re    2926   EINVAL   invalid register ID, or no such register or used with VMs in
2927            protected virtualization mode on s    2927            protected virtualization mode on s390
2928   EPERM    (arm64) register access not allowe    2928   EPERM    (arm64) register access not allowed before vcpu finalization
2929   ======== ==================================    2929   ======== ============================================================
2930                                                  2930 
2931 (These error codes are indicative only: do no    2931 (These error codes are indicative only: do not rely on a specific error
2932 code being returned in a specific situation.)    2932 code being returned in a specific situation.)
2933                                                  2933 
2934 This ioctl allows to receive the value of a s    2934 This ioctl allows to receive the value of a single register implemented
2935 in a vcpu. The register to read is indicated     2935 in a vcpu. The register to read is indicated by the "id" field of the
2936 kvm_one_reg struct passed in. On success, the    2936 kvm_one_reg struct passed in. On success, the register value can be found
2937 at the memory location pointed to by "addr".     2937 at the memory location pointed to by "addr".
2938                                                  2938 
2939 The list of registers accessible using this i    2939 The list of registers accessible using this interface is identical to the
2940 list in 4.68.                                    2940 list in 4.68.
2941                                                  2941 
2942                                                  2942 
2943 4.70 KVM_KVMCLOCK_CTRL                           2943 4.70 KVM_KVMCLOCK_CTRL
2944 ----------------------                           2944 ----------------------
2945                                                  2945 
2946 :Capability: KVM_CAP_KVMCLOCK_CTRL               2946 :Capability: KVM_CAP_KVMCLOCK_CTRL
2947 :Architectures: Any that implement pvclocks (    2947 :Architectures: Any that implement pvclocks (currently x86 only)
2948 :Type: vcpu ioctl                                2948 :Type: vcpu ioctl
2949 :Parameters: None                                2949 :Parameters: None
2950 :Returns: 0 on success, -1 on error              2950 :Returns: 0 on success, -1 on error
2951                                                  2951 
2952 This ioctl sets a flag accessible to the gues    2952 This ioctl sets a flag accessible to the guest indicating that the specified
2953 vCPU has been paused by the host userspace.      2953 vCPU has been paused by the host userspace.
2954                                                  2954 
2955 The host will set a flag in the pvclock struc    2955 The host will set a flag in the pvclock structure that is checked from the
2956 soft lockup watchdog.  The flag is part of th    2956 soft lockup watchdog.  The flag is part of the pvclock structure that is
2957 shared between guest and host, specifically t    2957 shared between guest and host, specifically the second bit of the flags
2958 field of the pvclock_vcpu_time_info structure    2958 field of the pvclock_vcpu_time_info structure.  It will be set exclusively by
2959 the host and read/cleared exclusively by the     2959 the host and read/cleared exclusively by the guest.  The guest operation of
2960 checking and clearing the flag must be an ato    2960 checking and clearing the flag must be an atomic operation so
2961 load-link/store-conditional, or equivalent mu    2961 load-link/store-conditional, or equivalent must be used.  There are two cases
2962 where the guest will clear the flag: when the    2962 where the guest will clear the flag: when the soft lockup watchdog timer resets
2963 itself or when a soft lockup is detected.  Th    2963 itself or when a soft lockup is detected.  This ioctl can be called any time
2964 after pausing the vcpu, but before it is resu    2964 after pausing the vcpu, but before it is resumed.
2965                                                  2965 
2966                                                  2966 
2967 4.71 KVM_SIGNAL_MSI                              2967 4.71 KVM_SIGNAL_MSI
2968 -------------------                              2968 -------------------
2969                                                  2969 
2970 :Capability: KVM_CAP_SIGNAL_MSI                  2970 :Capability: KVM_CAP_SIGNAL_MSI
2971 :Architectures: x86 arm64                        2971 :Architectures: x86 arm64
2972 :Type: vm ioctl                                  2972 :Type: vm ioctl
2973 :Parameters: struct kvm_msi (in)                 2973 :Parameters: struct kvm_msi (in)
2974 :Returns: >0 on delivery, 0 if guest blocked     2974 :Returns: >0 on delivery, 0 if guest blocked the MSI, and -1 on error
2975                                                  2975 
2976 Directly inject a MSI message. Only valid wit    2976 Directly inject a MSI message. Only valid with in-kernel irqchip that handles
2977 MSI messages.                                    2977 MSI messages.
2978                                                  2978 
2979 ::                                               2979 ::
2980                                                  2980 
2981   struct kvm_msi {                               2981   struct kvm_msi {
2982         __u32 address_lo;                        2982         __u32 address_lo;
2983         __u32 address_hi;                        2983         __u32 address_hi;
2984         __u32 data;                              2984         __u32 data;
2985         __u32 flags;                             2985         __u32 flags;
2986         __u32 devid;                             2986         __u32 devid;
2987         __u8  pad[12];                           2987         __u8  pad[12];
2988   };                                             2988   };
2989                                                  2989 
2990 flags:                                           2990 flags:
2991   KVM_MSI_VALID_DEVID: devid contains a valid    2991   KVM_MSI_VALID_DEVID: devid contains a valid value.  The per-VM
2992   KVM_CAP_MSI_DEVID capability advertises the    2992   KVM_CAP_MSI_DEVID capability advertises the requirement to provide
2993   the device ID.  If this capability is not a    2993   the device ID.  If this capability is not available, userspace
2994   should never set the KVM_MSI_VALID_DEVID fl    2994   should never set the KVM_MSI_VALID_DEVID flag as the ioctl might fail.
2995                                                  2995 
2996 If KVM_MSI_VALID_DEVID is set, devid contains    2996 If KVM_MSI_VALID_DEVID is set, devid contains a unique device identifier
2997 for the device that wrote the MSI message.  F    2997 for the device that wrote the MSI message.  For PCI, this is usually a
2998 BDF identifier in the lower 16 bits.             2998 BDF identifier in the lower 16 bits.
2999                                                  2999 
3000 On x86, address_hi is ignored unless the KVM_    3000 On x86, address_hi is ignored unless the KVM_X2APIC_API_USE_32BIT_IDS
3001 feature of KVM_CAP_X2APIC_API capability is e    3001 feature of KVM_CAP_X2APIC_API capability is enabled.  If it is enabled,
3002 address_hi bits 31-8 provide bits 31-8 of the    3002 address_hi bits 31-8 provide bits 31-8 of the destination id.  Bits 7-0 of
3003 address_hi must be zero.                         3003 address_hi must be zero.
3004                                                  3004 
3005                                                  3005 
3006 4.71 KVM_CREATE_PIT2                             3006 4.71 KVM_CREATE_PIT2
3007 --------------------                             3007 --------------------
3008                                                  3008 
3009 :Capability: KVM_CAP_PIT2                        3009 :Capability: KVM_CAP_PIT2
3010 :Architectures: x86                              3010 :Architectures: x86
3011 :Type: vm ioctl                                  3011 :Type: vm ioctl
3012 :Parameters: struct kvm_pit_config (in)          3012 :Parameters: struct kvm_pit_config (in)
3013 :Returns: 0 on success, -1 on error              3013 :Returns: 0 on success, -1 on error
3014                                                  3014 
3015 Creates an in-kernel device model for the i82    3015 Creates an in-kernel device model for the i8254 PIT. This call is only valid
3016 after enabling in-kernel irqchip support via     3016 after enabling in-kernel irqchip support via KVM_CREATE_IRQCHIP. The following
3017 parameters have to be passed::                   3017 parameters have to be passed::
3018                                                  3018 
3019   struct kvm_pit_config {                        3019   struct kvm_pit_config {
3020         __u32 flags;                             3020         __u32 flags;
3021         __u32 pad[15];                           3021         __u32 pad[15];
3022   };                                             3022   };
3023                                                  3023 
3024 Valid flags are::                                3024 Valid flags are::
3025                                                  3025 
3026   #define KVM_PIT_SPEAKER_DUMMY     1 /* emul    3026   #define KVM_PIT_SPEAKER_DUMMY     1 /* emulate speaker port stub */
3027                                                  3027 
3028 PIT timer interrupts may use a per-VM kernel     3028 PIT timer interrupts may use a per-VM kernel thread for injection. If it
3029 exists, this thread will have a name of the f    3029 exists, this thread will have a name of the following pattern::
3030                                                  3030 
3031   kvm-pit/<owner-process-pid>                    3031   kvm-pit/<owner-process-pid>
3032                                                  3032 
3033 When running a guest with elevated priorities    3033 When running a guest with elevated priorities, the scheduling parameters of
3034 this thread may have to be adjusted according    3034 this thread may have to be adjusted accordingly.
3035                                                  3035 
3036 This IOCTL replaces the obsolete KVM_CREATE_P    3036 This IOCTL replaces the obsolete KVM_CREATE_PIT.
3037                                                  3037 
3038                                                  3038 
3039 4.72 KVM_GET_PIT2                                3039 4.72 KVM_GET_PIT2
3040 -----------------                                3040 -----------------
3041                                                  3041 
3042 :Capability: KVM_CAP_PIT_STATE2                  3042 :Capability: KVM_CAP_PIT_STATE2
3043 :Architectures: x86                              3043 :Architectures: x86
3044 :Type: vm ioctl                                  3044 :Type: vm ioctl
3045 :Parameters: struct kvm_pit_state2 (out)         3045 :Parameters: struct kvm_pit_state2 (out)
3046 :Returns: 0 on success, -1 on error              3046 :Returns: 0 on success, -1 on error
3047                                                  3047 
3048 Retrieves the state of the in-kernel PIT mode    3048 Retrieves the state of the in-kernel PIT model. Only valid after
3049 KVM_CREATE_PIT2. The state is returned in the    3049 KVM_CREATE_PIT2. The state is returned in the following structure::
3050                                                  3050 
3051   struct kvm_pit_state2 {                        3051   struct kvm_pit_state2 {
3052         struct kvm_pit_channel_state channels    3052         struct kvm_pit_channel_state channels[3];
3053         __u32 flags;                             3053         __u32 flags;
3054         __u32 reserved[9];                       3054         __u32 reserved[9];
3055   };                                             3055   };
3056                                                  3056 
3057 Valid flags are::                                3057 Valid flags are::
3058                                                  3058 
3059   /* disable PIT in HPET legacy mode */          3059   /* disable PIT in HPET legacy mode */
3060   #define KVM_PIT_FLAGS_HPET_LEGACY     0x000    3060   #define KVM_PIT_FLAGS_HPET_LEGACY     0x00000001
3061   /* speaker port data bit enabled */            3061   /* speaker port data bit enabled */
3062   #define KVM_PIT_FLAGS_SPEAKER_DATA_ON 0x000    3062   #define KVM_PIT_FLAGS_SPEAKER_DATA_ON 0x00000002
3063                                                  3063 
3064 This IOCTL replaces the obsolete KVM_GET_PIT.    3064 This IOCTL replaces the obsolete KVM_GET_PIT.
3065                                                  3065 
3066                                                  3066 
3067 4.73 KVM_SET_PIT2                                3067 4.73 KVM_SET_PIT2
3068 -----------------                                3068 -----------------
3069                                                  3069 
3070 :Capability: KVM_CAP_PIT_STATE2                  3070 :Capability: KVM_CAP_PIT_STATE2
3071 :Architectures: x86                              3071 :Architectures: x86
3072 :Type: vm ioctl                                  3072 :Type: vm ioctl
3073 :Parameters: struct kvm_pit_state2 (in)          3073 :Parameters: struct kvm_pit_state2 (in)
3074 :Returns: 0 on success, -1 on error              3074 :Returns: 0 on success, -1 on error
3075                                                  3075 
3076 Sets the state of the in-kernel PIT model. On    3076 Sets the state of the in-kernel PIT model. Only valid after KVM_CREATE_PIT2.
3077 See KVM_GET_PIT2 for details on struct kvm_pi    3077 See KVM_GET_PIT2 for details on struct kvm_pit_state2.
3078                                                  3078 
3079 This IOCTL replaces the obsolete KVM_SET_PIT.    3079 This IOCTL replaces the obsolete KVM_SET_PIT.
3080                                                  3080 
3081                                                  3081 
3082 4.74 KVM_PPC_GET_SMMU_INFO                       3082 4.74 KVM_PPC_GET_SMMU_INFO
3083 --------------------------                       3083 --------------------------
3084                                                  3084 
3085 :Capability: KVM_CAP_PPC_GET_SMMU_INFO           3085 :Capability: KVM_CAP_PPC_GET_SMMU_INFO
3086 :Architectures: powerpc                          3086 :Architectures: powerpc
3087 :Type: vm ioctl                                  3087 :Type: vm ioctl
3088 :Parameters: None                                3088 :Parameters: None
3089 :Returns: 0 on success, -1 on error              3089 :Returns: 0 on success, -1 on error
3090                                                  3090 
3091 This populates and returns a structure descri    3091 This populates and returns a structure describing the features of
3092 the "Server" class MMU emulation supported by    3092 the "Server" class MMU emulation supported by KVM.
3093 This can in turn be used by userspace to gene    3093 This can in turn be used by userspace to generate the appropriate
3094 device-tree properties for the guest operatin    3094 device-tree properties for the guest operating system.
3095                                                  3095 
3096 The structure contains some global informatio    3096 The structure contains some global information, followed by an
3097 array of supported segment page sizes::          3097 array of supported segment page sizes::
3098                                                  3098 
3099       struct kvm_ppc_smmu_info {                 3099       struct kvm_ppc_smmu_info {
3100              __u64 flags;                        3100              __u64 flags;
3101              __u32 slb_size;                     3101              __u32 slb_size;
3102              __u32 pad;                          3102              __u32 pad;
3103              struct kvm_ppc_one_seg_page_size    3103              struct kvm_ppc_one_seg_page_size sps[KVM_PPC_PAGE_SIZES_MAX_SZ];
3104       };                                         3104       };
3105                                                  3105 
3106 The supported flags are:                         3106 The supported flags are:
3107                                                  3107 
3108     - KVM_PPC_PAGE_SIZES_REAL:                   3108     - KVM_PPC_PAGE_SIZES_REAL:
3109         When that flag is set, guest page siz    3109         When that flag is set, guest page sizes must "fit" the backing
3110         store page sizes. When not set, any p    3110         store page sizes. When not set, any page size in the list can
3111         be used regardless of how they are ba    3111         be used regardless of how they are backed by userspace.
3112                                                  3112 
3113     - KVM_PPC_1T_SEGMENTS                        3113     - KVM_PPC_1T_SEGMENTS
3114         The emulated MMU supports 1T segments    3114         The emulated MMU supports 1T segments in addition to the
3115         standard 256M ones.                      3115         standard 256M ones.
3116                                                  3116 
3117     - KVM_PPC_NO_HASH                            3117     - KVM_PPC_NO_HASH
3118         This flag indicates that HPT guests a    3118         This flag indicates that HPT guests are not supported by KVM,
3119         thus all guests must use radix MMU mo    3119         thus all guests must use radix MMU mode.
3120                                                  3120 
3121 The "slb_size" field indicates how many SLB e    3121 The "slb_size" field indicates how many SLB entries are supported
3122                                                  3122 
3123 The "sps" array contains 8 entries indicating    3123 The "sps" array contains 8 entries indicating the supported base
3124 page sizes for a segment in increasing order.    3124 page sizes for a segment in increasing order. Each entry is defined
3125 as follow::                                      3125 as follow::
3126                                                  3126 
3127    struct kvm_ppc_one_seg_page_size {            3127    struct kvm_ppc_one_seg_page_size {
3128         __u32 page_shift;       /* Base page     3128         __u32 page_shift;       /* Base page shift of segment (or 0) */
3129         __u32 slb_enc;          /* SLB encodi    3129         __u32 slb_enc;          /* SLB encoding for BookS */
3130         struct kvm_ppc_one_page_size enc[KVM_    3130         struct kvm_ppc_one_page_size enc[KVM_PPC_PAGE_SIZES_MAX_SZ];
3131    };                                            3131    };
3132                                                  3132 
3133 An entry with a "page_shift" of 0 is unused.     3133 An entry with a "page_shift" of 0 is unused. Because the array is
3134 organized in increasing order, a lookup can s    3134 organized in increasing order, a lookup can stop when encountering
3135 such an entry.                                   3135 such an entry.
3136                                                  3136 
3137 The "slb_enc" field provides the encoding to     3137 The "slb_enc" field provides the encoding to use in the SLB for the
3138 page size. The bits are in positions such as     3138 page size. The bits are in positions such as the value can directly
3139 be OR'ed into the "vsid" argument of the slbm    3139 be OR'ed into the "vsid" argument of the slbmte instruction.
3140                                                  3140 
3141 The "enc" array is a list which for each of t    3141 The "enc" array is a list which for each of those segment base page
3142 size provides the list of supported actual pa    3142 size provides the list of supported actual page sizes (which can be
3143 only larger or equal to the base page size),     3143 only larger or equal to the base page size), along with the
3144 corresponding encoding in the hash PTE. Simil    3144 corresponding encoding in the hash PTE. Similarly, the array is
3145 8 entries sorted by increasing sizes and an e    3145 8 entries sorted by increasing sizes and an entry with a "0" shift
3146 is an empty entry and a terminator::             3146 is an empty entry and a terminator::
3147                                                  3147 
3148    struct kvm_ppc_one_page_size {                3148    struct kvm_ppc_one_page_size {
3149         __u32 page_shift;       /* Page shift    3149         __u32 page_shift;       /* Page shift (or 0) */
3150         __u32 pte_enc;          /* Encoding i    3150         __u32 pte_enc;          /* Encoding in the HPTE (>>12) */
3151    };                                            3151    };
3152                                                  3152 
3153 The "pte_enc" field provides a value that can    3153 The "pte_enc" field provides a value that can OR'ed into the hash
3154 PTE's RPN field (ie, it needs to be shifted l    3154 PTE's RPN field (ie, it needs to be shifted left by 12 to OR it
3155 into the hash PTE second double word).           3155 into the hash PTE second double word).
3156                                                  3156 
3157 4.75 KVM_IRQFD                                   3157 4.75 KVM_IRQFD
3158 --------------                                   3158 --------------
3159                                                  3159 
3160 :Capability: KVM_CAP_IRQFD                       3160 :Capability: KVM_CAP_IRQFD
3161 :Architectures: x86 s390 arm64                   3161 :Architectures: x86 s390 arm64
3162 :Type: vm ioctl                                  3162 :Type: vm ioctl
3163 :Parameters: struct kvm_irqfd (in)               3163 :Parameters: struct kvm_irqfd (in)
3164 :Returns: 0 on success, -1 on error              3164 :Returns: 0 on success, -1 on error
3165                                                  3165 
3166 Allows setting an eventfd to directly trigger    3166 Allows setting an eventfd to directly trigger a guest interrupt.
3167 kvm_irqfd.fd specifies the file descriptor to    3167 kvm_irqfd.fd specifies the file descriptor to use as the eventfd and
3168 kvm_irqfd.gsi specifies the irqchip pin toggl    3168 kvm_irqfd.gsi specifies the irqchip pin toggled by this event.  When
3169 an event is triggered on the eventfd, an inte    3169 an event is triggered on the eventfd, an interrupt is injected into
3170 the guest using the specified gsi pin.  The i    3170 the guest using the specified gsi pin.  The irqfd is removed using
3171 the KVM_IRQFD_FLAG_DEASSIGN flag, specifying     3171 the KVM_IRQFD_FLAG_DEASSIGN flag, specifying both kvm_irqfd.fd
3172 and kvm_irqfd.gsi.                               3172 and kvm_irqfd.gsi.
3173                                                  3173 
3174 With KVM_CAP_IRQFD_RESAMPLE, KVM_IRQFD suppor    3174 With KVM_CAP_IRQFD_RESAMPLE, KVM_IRQFD supports a de-assert and notify
3175 mechanism allowing emulation of level-trigger    3175 mechanism allowing emulation of level-triggered, irqfd-based
3176 interrupts.  When KVM_IRQFD_FLAG_RESAMPLE is     3176 interrupts.  When KVM_IRQFD_FLAG_RESAMPLE is set the user must pass an
3177 additional eventfd in the kvm_irqfd.resamplef    3177 additional eventfd in the kvm_irqfd.resamplefd field.  When operating
3178 in resample mode, posting of an interrupt thr    3178 in resample mode, posting of an interrupt through kvm_irq.fd asserts
3179 the specified gsi in the irqchip.  When the i    3179 the specified gsi in the irqchip.  When the irqchip is resampled, such
3180 as from an EOI, the gsi is de-asserted and th    3180 as from an EOI, the gsi is de-asserted and the user is notified via
3181 kvm_irqfd.resamplefd.  It is the user's respo    3181 kvm_irqfd.resamplefd.  It is the user's responsibility to re-queue
3182 the interrupt if the device making use of it     3182 the interrupt if the device making use of it still requires service.
3183 Note that closing the resamplefd is not suffi    3183 Note that closing the resamplefd is not sufficient to disable the
3184 irqfd.  The KVM_IRQFD_FLAG_RESAMPLE is only n    3184 irqfd.  The KVM_IRQFD_FLAG_RESAMPLE is only necessary on assignment
3185 and need not be specified with KVM_IRQFD_FLAG    3185 and need not be specified with KVM_IRQFD_FLAG_DEASSIGN.
3186                                                  3186 
3187 On arm64, gsi routing being supported, the fo    3187 On arm64, gsi routing being supported, the following can happen:
3188                                                  3188 
3189 - in case no routing entry is associated to t    3189 - in case no routing entry is associated to this gsi, injection fails
3190 - in case the gsi is associated to an irqchip    3190 - in case the gsi is associated to an irqchip routing entry,
3191   irqchip.pin + 32 corresponds to the injecte    3191   irqchip.pin + 32 corresponds to the injected SPI ID.
3192 - in case the gsi is associated to an MSI rou    3192 - in case the gsi is associated to an MSI routing entry, the MSI
3193   message and device ID are translated into a    3193   message and device ID are translated into an LPI (support restricted
3194   to GICv3 ITS in-kernel emulation).             3194   to GICv3 ITS in-kernel emulation).
3195                                                  3195 
3196 4.76 KVM_PPC_ALLOCATE_HTAB                       3196 4.76 KVM_PPC_ALLOCATE_HTAB
3197 --------------------------                       3197 --------------------------
3198                                                  3198 
3199 :Capability: KVM_CAP_PPC_ALLOC_HTAB              3199 :Capability: KVM_CAP_PPC_ALLOC_HTAB
3200 :Architectures: powerpc                          3200 :Architectures: powerpc
3201 :Type: vm ioctl                                  3201 :Type: vm ioctl
3202 :Parameters: Pointer to u32 containing hash t    3202 :Parameters: Pointer to u32 containing hash table order (in/out)
3203 :Returns: 0 on success, -1 on error              3203 :Returns: 0 on success, -1 on error
3204                                                  3204 
3205 This requests the host kernel to allocate an     3205 This requests the host kernel to allocate an MMU hash table for a
3206 guest using the PAPR paravirtualization inter    3206 guest using the PAPR paravirtualization interface.  This only does
3207 anything if the kernel is configured to use t    3207 anything if the kernel is configured to use the Book 3S HV style of
3208 virtualization.  Otherwise the capability doe    3208 virtualization.  Otherwise the capability doesn't exist and the ioctl
3209 returns an ENOTTY error.  The rest of this de    3209 returns an ENOTTY error.  The rest of this description assumes Book 3S
3210 HV.                                              3210 HV.
3211                                                  3211 
3212 There must be no vcpus running when this ioct    3212 There must be no vcpus running when this ioctl is called; if there
3213 are, it will do nothing and return an EBUSY e    3213 are, it will do nothing and return an EBUSY error.
3214                                                  3214 
3215 The parameter is a pointer to a 32-bit unsign    3215 The parameter is a pointer to a 32-bit unsigned integer variable
3216 containing the order (log base 2) of the desi    3216 containing the order (log base 2) of the desired size of the hash
3217 table, which must be between 18 and 46.  On s    3217 table, which must be between 18 and 46.  On successful return from the
3218 ioctl, the value will not be changed by the k    3218 ioctl, the value will not be changed by the kernel.
3219                                                  3219 
3220 If no hash table has been allocated when any     3220 If no hash table has been allocated when any vcpu is asked to run
3221 (with the KVM_RUN ioctl), the host kernel wil    3221 (with the KVM_RUN ioctl), the host kernel will allocate a
3222 default-sized hash table (16 MB).                3222 default-sized hash table (16 MB).
3223                                                  3223 
3224 If this ioctl is called when a hash table has    3224 If this ioctl is called when a hash table has already been allocated,
3225 with a different order from the existing hash    3225 with a different order from the existing hash table, the existing hash
3226 table will be freed and a new one allocated.     3226 table will be freed and a new one allocated.  If this is ioctl is
3227 called when a hash table has already been all    3227 called when a hash table has already been allocated of the same order
3228 as specified, the kernel will clear out the e    3228 as specified, the kernel will clear out the existing hash table (zero
3229 all HPTEs).  In either case, if the guest is     3229 all HPTEs).  In either case, if the guest is using the virtualized
3230 real-mode area (VRMA) facility, the kernel wi    3230 real-mode area (VRMA) facility, the kernel will re-create the VMRA
3231 HPTEs on the next KVM_RUN of any vcpu.           3231 HPTEs on the next KVM_RUN of any vcpu.
3232                                                  3232 
3233 4.77 KVM_S390_INTERRUPT                          3233 4.77 KVM_S390_INTERRUPT
3234 -----------------------                          3234 -----------------------
3235                                                  3235 
3236 :Capability: basic                               3236 :Capability: basic
3237 :Architectures: s390                             3237 :Architectures: s390
3238 :Type: vm ioctl, vcpu ioctl                      3238 :Type: vm ioctl, vcpu ioctl
3239 :Parameters: struct kvm_s390_interrupt (in)      3239 :Parameters: struct kvm_s390_interrupt (in)
3240 :Returns: 0 on success, -1 on error              3240 :Returns: 0 on success, -1 on error
3241                                                  3241 
3242 Allows to inject an interrupt to the guest. I    3242 Allows to inject an interrupt to the guest. Interrupts can be floating
3243 (vm ioctl) or per cpu (vcpu ioctl), depending    3243 (vm ioctl) or per cpu (vcpu ioctl), depending on the interrupt type.
3244                                                  3244 
3245 Interrupt parameters are passed via kvm_s390_    3245 Interrupt parameters are passed via kvm_s390_interrupt::
3246                                                  3246 
3247   struct kvm_s390_interrupt {                    3247   struct kvm_s390_interrupt {
3248         __u32 type;                              3248         __u32 type;
3249         __u32 parm;                              3249         __u32 parm;
3250         __u64 parm64;                            3250         __u64 parm64;
3251   };                                             3251   };
3252                                                  3252 
3253 type can be one of the following:                3253 type can be one of the following:
3254                                                  3254 
3255 KVM_S390_SIGP_STOP (vcpu)                        3255 KVM_S390_SIGP_STOP (vcpu)
3256     - sigp stop; optional flags in parm          3256     - sigp stop; optional flags in parm
3257 KVM_S390_PROGRAM_INT (vcpu)                      3257 KVM_S390_PROGRAM_INT (vcpu)
3258     - program check; code in parm                3258     - program check; code in parm
3259 KVM_S390_SIGP_SET_PREFIX (vcpu)                  3259 KVM_S390_SIGP_SET_PREFIX (vcpu)
3260     - sigp set prefix; prefix address in parm    3260     - sigp set prefix; prefix address in parm
3261 KVM_S390_RESTART (vcpu)                          3261 KVM_S390_RESTART (vcpu)
3262     - restart                                    3262     - restart
3263 KVM_S390_INT_CLOCK_COMP (vcpu)                   3263 KVM_S390_INT_CLOCK_COMP (vcpu)
3264     - clock comparator interrupt                 3264     - clock comparator interrupt
3265 KVM_S390_INT_CPU_TIMER (vcpu)                    3265 KVM_S390_INT_CPU_TIMER (vcpu)
3266     - CPU timer interrupt                        3266     - CPU timer interrupt
3267 KVM_S390_INT_VIRTIO (vm)                         3267 KVM_S390_INT_VIRTIO (vm)
3268     - virtio external interrupt; external int    3268     - virtio external interrupt; external interrupt
3269       parameters in parm and parm64              3269       parameters in parm and parm64
3270 KVM_S390_INT_SERVICE (vm)                        3270 KVM_S390_INT_SERVICE (vm)
3271     - sclp external interrupt; sclp parameter    3271     - sclp external interrupt; sclp parameter in parm
3272 KVM_S390_INT_EMERGENCY (vcpu)                    3272 KVM_S390_INT_EMERGENCY (vcpu)
3273     - sigp emergency; source cpu in parm         3273     - sigp emergency; source cpu in parm
3274 KVM_S390_INT_EXTERNAL_CALL (vcpu)                3274 KVM_S390_INT_EXTERNAL_CALL (vcpu)
3275     - sigp external call; source cpu in parm     3275     - sigp external call; source cpu in parm
3276 KVM_S390_INT_IO(ai,cssid,ssid,schid) (vm)        3276 KVM_S390_INT_IO(ai,cssid,ssid,schid) (vm)
3277     - compound value to indicate an              3277     - compound value to indicate an
3278       I/O interrupt (ai - adapter interrupt;     3278       I/O interrupt (ai - adapter interrupt; cssid,ssid,schid - subchannel);
3279       I/O interruption parameters in parm (su    3279       I/O interruption parameters in parm (subchannel) and parm64 (intparm,
3280       interruption subclass)                     3280       interruption subclass)
3281 KVM_S390_MCHK (vm, vcpu)                         3281 KVM_S390_MCHK (vm, vcpu)
3282     - machine check interrupt; cr 14 bits in     3282     - machine check interrupt; cr 14 bits in parm, machine check interrupt
3283       code in parm64 (note that machine check    3283       code in parm64 (note that machine checks needing further payload are not
3284       supported by this ioctl)                   3284       supported by this ioctl)
3285                                                  3285 
3286 This is an asynchronous vcpu ioctl and can be    3286 This is an asynchronous vcpu ioctl and can be invoked from any thread.
3287                                                  3287 
3288 4.78 KVM_PPC_GET_HTAB_FD                         3288 4.78 KVM_PPC_GET_HTAB_FD
3289 ------------------------                         3289 ------------------------
3290                                                  3290 
3291 :Capability: KVM_CAP_PPC_HTAB_FD                 3291 :Capability: KVM_CAP_PPC_HTAB_FD
3292 :Architectures: powerpc                          3292 :Architectures: powerpc
3293 :Type: vm ioctl                                  3293 :Type: vm ioctl
3294 :Parameters: Pointer to struct kvm_get_htab_f    3294 :Parameters: Pointer to struct kvm_get_htab_fd (in)
3295 :Returns: file descriptor number (>= 0) on su    3295 :Returns: file descriptor number (>= 0) on success, -1 on error
3296                                                  3296 
3297 This returns a file descriptor that can be us    3297 This returns a file descriptor that can be used either to read out the
3298 entries in the guest's hashed page table (HPT    3298 entries in the guest's hashed page table (HPT), or to write entries to
3299 initialize the HPT.  The returned fd can only    3299 initialize the HPT.  The returned fd can only be written to if the
3300 KVM_GET_HTAB_WRITE bit is set in the flags fi    3300 KVM_GET_HTAB_WRITE bit is set in the flags field of the argument, and
3301 can only be read if that bit is clear.  The a    3301 can only be read if that bit is clear.  The argument struct looks like
3302 this::                                           3302 this::
3303                                                  3303 
3304   /* For KVM_PPC_GET_HTAB_FD */                  3304   /* For KVM_PPC_GET_HTAB_FD */
3305   struct kvm_get_htab_fd {                       3305   struct kvm_get_htab_fd {
3306         __u64   flags;                           3306         __u64   flags;
3307         __u64   start_index;                     3307         __u64   start_index;
3308         __u64   reserved[2];                     3308         __u64   reserved[2];
3309   };                                             3309   };
3310                                                  3310 
3311   /* Values for kvm_get_htab_fd.flags */         3311   /* Values for kvm_get_htab_fd.flags */
3312   #define KVM_GET_HTAB_BOLTED_ONLY      ((__u    3312   #define KVM_GET_HTAB_BOLTED_ONLY      ((__u64)0x1)
3313   #define KVM_GET_HTAB_WRITE            ((__u    3313   #define KVM_GET_HTAB_WRITE            ((__u64)0x2)
3314                                                  3314 
3315 The 'start_index' field gives the index in th    3315 The 'start_index' field gives the index in the HPT of the entry at
3316 which to start reading.  It is ignored when w    3316 which to start reading.  It is ignored when writing.
3317                                                  3317 
3318 Reads on the fd will initially supply informa    3318 Reads on the fd will initially supply information about all
3319 "interesting" HPT entries.  Interesting entri    3319 "interesting" HPT entries.  Interesting entries are those with the
3320 bolted bit set, if the KVM_GET_HTAB_BOLTED_ON    3320 bolted bit set, if the KVM_GET_HTAB_BOLTED_ONLY bit is set, otherwise
3321 all entries.  When the end of the HPT is reac    3321 all entries.  When the end of the HPT is reached, the read() will
3322 return.  If read() is called again on the fd,    3322 return.  If read() is called again on the fd, it will start again from
3323 the beginning of the HPT, but will only retur    3323 the beginning of the HPT, but will only return HPT entries that have
3324 changed since they were last read.               3324 changed since they were last read.
3325                                                  3325 
3326 Data read or written is structured as a heade    3326 Data read or written is structured as a header (8 bytes) followed by a
3327 series of valid HPT entries (16 bytes) each.     3327 series of valid HPT entries (16 bytes) each.  The header indicates how
3328 many valid HPT entries there are and how many    3328 many valid HPT entries there are and how many invalid entries follow
3329 the valid entries.  The invalid entries are n    3329 the valid entries.  The invalid entries are not represented explicitly
3330 in the stream.  The header format is::           3330 in the stream.  The header format is::
3331                                                  3331 
3332   struct kvm_get_htab_header {                   3332   struct kvm_get_htab_header {
3333         __u32   index;                           3333         __u32   index;
3334         __u16   n_valid;                         3334         __u16   n_valid;
3335         __u16   n_invalid;                       3335         __u16   n_invalid;
3336   };                                             3336   };
3337                                                  3337 
3338 Writes to the fd create HPT entries starting     3338 Writes to the fd create HPT entries starting at the index given in the
3339 header; first 'n_valid' valid entries with co    3339 header; first 'n_valid' valid entries with contents from the data
3340 written, then 'n_invalid' invalid entries, in    3340 written, then 'n_invalid' invalid entries, invalidating any previously
3341 valid entries found.                             3341 valid entries found.
3342                                                  3342 
3343 4.79 KVM_CREATE_DEVICE                           3343 4.79 KVM_CREATE_DEVICE
3344 ----------------------                           3344 ----------------------
3345                                                  3345 
3346 :Capability: KVM_CAP_DEVICE_CTRL                 3346 :Capability: KVM_CAP_DEVICE_CTRL
3347 :Architectures: all                              3347 :Architectures: all
3348 :Type: vm ioctl                                  3348 :Type: vm ioctl
3349 :Parameters: struct kvm_create_device (in/out    3349 :Parameters: struct kvm_create_device (in/out)
3350 :Returns: 0 on success, -1 on error              3350 :Returns: 0 on success, -1 on error
3351                                                  3351 
3352 Errors:                                          3352 Errors:
3353                                                  3353 
3354   ======  ===================================    3354   ======  =======================================================
3355   ENODEV  The device type is unknown or unsup    3355   ENODEV  The device type is unknown or unsupported
3356   EEXIST  Device already created, and this ty    3356   EEXIST  Device already created, and this type of device may not
3357           be instantiated multiple times         3357           be instantiated multiple times
3358   ======  ===================================    3358   ======  =======================================================
3359                                                  3359 
3360   Other error conditions may be defined by in    3360   Other error conditions may be defined by individual device types or
3361   have their standard meanings.                  3361   have their standard meanings.
3362                                                  3362 
3363 Creates an emulated device in the kernel.  Th    3363 Creates an emulated device in the kernel.  The file descriptor returned
3364 in fd can be used with KVM_SET/GET/HAS_DEVICE    3364 in fd can be used with KVM_SET/GET/HAS_DEVICE_ATTR.
3365                                                  3365 
3366 If the KVM_CREATE_DEVICE_TEST flag is set, on    3366 If the KVM_CREATE_DEVICE_TEST flag is set, only test whether the
3367 device type is supported (not necessarily whe    3367 device type is supported (not necessarily whether it can be created
3368 in the current vm).                              3368 in the current vm).
3369                                                  3369 
3370 Individual devices should not define flags.      3370 Individual devices should not define flags.  Attributes should be used
3371 for specifying any behavior that is not impli    3371 for specifying any behavior that is not implied by the device type
3372 number.                                          3372 number.
3373                                                  3373 
3374 ::                                               3374 ::
3375                                                  3375 
3376   struct kvm_create_device {                     3376   struct kvm_create_device {
3377         __u32   type;   /* in: KVM_DEV_TYPE_x    3377         __u32   type;   /* in: KVM_DEV_TYPE_xxx */
3378         __u32   fd;     /* out: device handle    3378         __u32   fd;     /* out: device handle */
3379         __u32   flags;  /* in: KVM_CREATE_DEV    3379         __u32   flags;  /* in: KVM_CREATE_DEVICE_xxx */
3380   };                                             3380   };
3381                                                  3381 
3382 4.80 KVM_SET_DEVICE_ATTR/KVM_GET_DEVICE_ATTR     3382 4.80 KVM_SET_DEVICE_ATTR/KVM_GET_DEVICE_ATTR
3383 --------------------------------------------     3383 --------------------------------------------
3384                                                  3384 
3385 :Capability: KVM_CAP_DEVICE_CTRL, KVM_CAP_VM_    3385 :Capability: KVM_CAP_DEVICE_CTRL, KVM_CAP_VM_ATTRIBUTES for vm device,
3386              KVM_CAP_VCPU_ATTRIBUTES for vcpu    3386              KVM_CAP_VCPU_ATTRIBUTES for vcpu device
3387              KVM_CAP_SYS_ATTRIBUTES for syste    3387              KVM_CAP_SYS_ATTRIBUTES for system (/dev/kvm) device (no set)
3388 :Architectures: x86, arm64, s390                 3388 :Architectures: x86, arm64, s390
3389 :Type: device ioctl, vm ioctl, vcpu ioctl        3389 :Type: device ioctl, vm ioctl, vcpu ioctl
3390 :Parameters: struct kvm_device_attr              3390 :Parameters: struct kvm_device_attr
3391 :Returns: 0 on success, -1 on error              3391 :Returns: 0 on success, -1 on error
3392                                                  3392 
3393 Errors:                                          3393 Errors:
3394                                                  3394 
3395   =====   ===================================    3395   =====   =============================================================
3396   ENXIO   The group or attribute is unknown/u    3396   ENXIO   The group or attribute is unknown/unsupported for this device
3397           or hardware support is missing.        3397           or hardware support is missing.
3398   EPERM   The attribute cannot (currently) be    3398   EPERM   The attribute cannot (currently) be accessed this way
3399           (e.g. read-only attribute, or attri    3399           (e.g. read-only attribute, or attribute that only makes
3400           sense when the device is in a diffe    3400           sense when the device is in a different state)
3401   =====   ===================================    3401   =====   =============================================================
3402                                                  3402 
3403   Other error conditions may be defined by in    3403   Other error conditions may be defined by individual device types.
3404                                                  3404 
3405 Gets/sets a specified piece of device configu    3405 Gets/sets a specified piece of device configuration and/or state.  The
3406 semantics are device-specific.  See individua    3406 semantics are device-specific.  See individual device documentation in
3407 the "devices" directory.  As with ONE_REG, th    3407 the "devices" directory.  As with ONE_REG, the size of the data
3408 transferred is defined by the particular attr    3408 transferred is defined by the particular attribute.
3409                                                  3409 
3410 ::                                               3410 ::
3411                                                  3411 
3412   struct kvm_device_attr {                       3412   struct kvm_device_attr {
3413         __u32   flags;          /* no flags c    3413         __u32   flags;          /* no flags currently defined */
3414         __u32   group;          /* device-def    3414         __u32   group;          /* device-defined */
3415         __u64   attr;           /* group-defi    3415         __u64   attr;           /* group-defined */
3416         __u64   addr;           /* userspace     3416         __u64   addr;           /* userspace address of attr data */
3417   };                                             3417   };
3418                                                  3418 
3419 4.81 KVM_HAS_DEVICE_ATTR                         3419 4.81 KVM_HAS_DEVICE_ATTR
3420 ------------------------                         3420 ------------------------
3421                                                  3421 
3422 :Capability: KVM_CAP_DEVICE_CTRL, KVM_CAP_VM_    3422 :Capability: KVM_CAP_DEVICE_CTRL, KVM_CAP_VM_ATTRIBUTES for vm device,
3423              KVM_CAP_VCPU_ATTRIBUTES for vcpu    3423              KVM_CAP_VCPU_ATTRIBUTES for vcpu device
3424              KVM_CAP_SYS_ATTRIBUTES for syste    3424              KVM_CAP_SYS_ATTRIBUTES for system (/dev/kvm) device
3425 :Type: device ioctl, vm ioctl, vcpu ioctl        3425 :Type: device ioctl, vm ioctl, vcpu ioctl
3426 :Parameters: struct kvm_device_attr              3426 :Parameters: struct kvm_device_attr
3427 :Returns: 0 on success, -1 on error              3427 :Returns: 0 on success, -1 on error
3428                                                  3428 
3429 Errors:                                          3429 Errors:
3430                                                  3430 
3431   =====   ===================================    3431   =====   =============================================================
3432   ENXIO   The group or attribute is unknown/u    3432   ENXIO   The group or attribute is unknown/unsupported for this device
3433           or hardware support is missing.        3433           or hardware support is missing.
3434   =====   ===================================    3434   =====   =============================================================
3435                                                  3435 
3436 Tests whether a device supports a particular     3436 Tests whether a device supports a particular attribute.  A successful
3437 return indicates the attribute is implemented    3437 return indicates the attribute is implemented.  It does not necessarily
3438 indicate that the attribute can be read or wr    3438 indicate that the attribute can be read or written in the device's
3439 current state.  "addr" is ignored.               3439 current state.  "addr" is ignored.
3440                                                  3440 
3441 .. _KVM_ARM_VCPU_INIT:                           3441 .. _KVM_ARM_VCPU_INIT:
3442                                                  3442 
3443 4.82 KVM_ARM_VCPU_INIT                           3443 4.82 KVM_ARM_VCPU_INIT
3444 ----------------------                           3444 ----------------------
3445                                                  3445 
3446 :Capability: basic                               3446 :Capability: basic
3447 :Architectures: arm64                            3447 :Architectures: arm64
3448 :Type: vcpu ioctl                                3448 :Type: vcpu ioctl
3449 :Parameters: struct kvm_vcpu_init (in)           3449 :Parameters: struct kvm_vcpu_init (in)
3450 :Returns: 0 on success; -1 on error              3450 :Returns: 0 on success; -1 on error
3451                                                  3451 
3452 Errors:                                          3452 Errors:
3453                                                  3453 
3454   ======     ================================    3454   ======     =================================================================
3455   EINVAL     the target is unknown, or the co    3455   EINVAL     the target is unknown, or the combination of features is invalid.
3456   ENOENT     a features bit specified is unkn    3456   ENOENT     a features bit specified is unknown.
3457   ======     ================================    3457   ======     =================================================================
3458                                                  3458 
3459 This tells KVM what type of CPU to present to    3459 This tells KVM what type of CPU to present to the guest, and what
3460 optional features it should have.  This will     3460 optional features it should have.  This will cause a reset of the cpu
3461 registers to their initial values.  If this i    3461 registers to their initial values.  If this is not called, KVM_RUN will
3462 return ENOEXEC for that vcpu.                    3462 return ENOEXEC for that vcpu.
3463                                                  3463 
3464 The initial values are defined as:               3464 The initial values are defined as:
3465         - Processor state:                       3465         - Processor state:
3466                 * AArch64: EL1h, D, A, I and     3466                 * AArch64: EL1h, D, A, I and F bits set. All other bits
3467                   are cleared.                   3467                   are cleared.
3468                 * AArch32: SVC, A, I and F bi    3468                 * AArch32: SVC, A, I and F bits set. All other bits are
3469                   cleared.                       3469                   cleared.
3470         - General Purpose registers, includin    3470         - General Purpose registers, including PC and SP: set to 0
3471         - FPSIMD/NEON registers: set to 0        3471         - FPSIMD/NEON registers: set to 0
3472         - SVE registers: set to 0                3472         - SVE registers: set to 0
3473         - System registers: Reset to their ar    3473         - System registers: Reset to their architecturally defined
3474           values as for a warm reset to EL1 (    3474           values as for a warm reset to EL1 (resp. SVC)
3475                                                  3475 
3476 Note that because some registers reflect mach    3476 Note that because some registers reflect machine topology, all vcpus
3477 should be created before this ioctl is invoke    3477 should be created before this ioctl is invoked.
3478                                                  3478 
3479 Userspace can call this function multiple tim    3479 Userspace can call this function multiple times for a given vcpu, including
3480 after the vcpu has been run. This will reset     3480 after the vcpu has been run. This will reset the vcpu to its initial
3481 state. All calls to this function after the i    3481 state. All calls to this function after the initial call must use the same
3482 target and same set of feature flags, otherwi    3482 target and same set of feature flags, otherwise EINVAL will be returned.
3483                                                  3483 
3484 Possible features:                               3484 Possible features:
3485                                                  3485 
3486         - KVM_ARM_VCPU_POWER_OFF: Starts the     3486         - KVM_ARM_VCPU_POWER_OFF: Starts the CPU in a power-off state.
3487           Depends on KVM_CAP_ARM_PSCI.  If no    3487           Depends on KVM_CAP_ARM_PSCI.  If not set, the CPU will be powered on
3488           and execute guest code when KVM_RUN    3488           and execute guest code when KVM_RUN is called.
3489         - KVM_ARM_VCPU_EL1_32BIT: Starts the     3489         - KVM_ARM_VCPU_EL1_32BIT: Starts the CPU in a 32bit mode.
3490           Depends on KVM_CAP_ARM_EL1_32BIT (a    3490           Depends on KVM_CAP_ARM_EL1_32BIT (arm64 only).
3491         - KVM_ARM_VCPU_PSCI_0_2: Emulate PSCI    3491         - KVM_ARM_VCPU_PSCI_0_2: Emulate PSCI v0.2 (or a future revision
3492           backward compatible with v0.2) for     3492           backward compatible with v0.2) for the CPU.
3493           Depends on KVM_CAP_ARM_PSCI_0_2.       3493           Depends on KVM_CAP_ARM_PSCI_0_2.
3494         - KVM_ARM_VCPU_PMU_V3: Emulate PMUv3     3494         - KVM_ARM_VCPU_PMU_V3: Emulate PMUv3 for the CPU.
3495           Depends on KVM_CAP_ARM_PMU_V3.         3495           Depends on KVM_CAP_ARM_PMU_V3.
3496                                                  3496 
3497         - KVM_ARM_VCPU_PTRAUTH_ADDRESS: Enabl    3497         - KVM_ARM_VCPU_PTRAUTH_ADDRESS: Enables Address Pointer authentication
3498           for arm64 only.                        3498           for arm64 only.
3499           Depends on KVM_CAP_ARM_PTRAUTH_ADDR    3499           Depends on KVM_CAP_ARM_PTRAUTH_ADDRESS.
3500           If KVM_CAP_ARM_PTRAUTH_ADDRESS and     3500           If KVM_CAP_ARM_PTRAUTH_ADDRESS and KVM_CAP_ARM_PTRAUTH_GENERIC are
3501           both present, then both KVM_ARM_VCP    3501           both present, then both KVM_ARM_VCPU_PTRAUTH_ADDRESS and
3502           KVM_ARM_VCPU_PTRAUTH_GENERIC must b    3502           KVM_ARM_VCPU_PTRAUTH_GENERIC must be requested or neither must be
3503           requested.                             3503           requested.
3504                                                  3504 
3505         - KVM_ARM_VCPU_PTRAUTH_GENERIC: Enabl    3505         - KVM_ARM_VCPU_PTRAUTH_GENERIC: Enables Generic Pointer authentication
3506           for arm64 only.                        3506           for arm64 only.
3507           Depends on KVM_CAP_ARM_PTRAUTH_GENE    3507           Depends on KVM_CAP_ARM_PTRAUTH_GENERIC.
3508           If KVM_CAP_ARM_PTRAUTH_ADDRESS and     3508           If KVM_CAP_ARM_PTRAUTH_ADDRESS and KVM_CAP_ARM_PTRAUTH_GENERIC are
3509           both present, then both KVM_ARM_VCP    3509           both present, then both KVM_ARM_VCPU_PTRAUTH_ADDRESS and
3510           KVM_ARM_VCPU_PTRAUTH_GENERIC must b    3510           KVM_ARM_VCPU_PTRAUTH_GENERIC must be requested or neither must be
3511           requested.                             3511           requested.
3512                                                  3512 
3513         - KVM_ARM_VCPU_SVE: Enables SVE for t    3513         - KVM_ARM_VCPU_SVE: Enables SVE for the CPU (arm64 only).
3514           Depends on KVM_CAP_ARM_SVE.            3514           Depends on KVM_CAP_ARM_SVE.
3515           Requires KVM_ARM_VCPU_FINALIZE(KVM_    3515           Requires KVM_ARM_VCPU_FINALIZE(KVM_ARM_VCPU_SVE):
3516                                                  3516 
3517            * After KVM_ARM_VCPU_INIT:            3517            * After KVM_ARM_VCPU_INIT:
3518                                                  3518 
3519               - KVM_REG_ARM64_SVE_VLS may be     3519               - KVM_REG_ARM64_SVE_VLS may be read using KVM_GET_ONE_REG: the
3520                 initial value of this pseudo-    3520                 initial value of this pseudo-register indicates the best set of
3521                 vector lengths possible for a    3521                 vector lengths possible for a vcpu on this host.
3522                                                  3522 
3523            * Before KVM_ARM_VCPU_FINALIZE(KVM    3523            * Before KVM_ARM_VCPU_FINALIZE(KVM_ARM_VCPU_SVE):
3524                                                  3524 
3525               - KVM_RUN and KVM_GET_REG_LIST     3525               - KVM_RUN and KVM_GET_REG_LIST are not available;
3526                                                  3526 
3527               - KVM_GET_ONE_REG and KVM_SET_O    3527               - KVM_GET_ONE_REG and KVM_SET_ONE_REG cannot be used to access
3528                 the scalable architectural SV    3528                 the scalable architectural SVE registers
3529                 KVM_REG_ARM64_SVE_ZREG(), KVM    3529                 KVM_REG_ARM64_SVE_ZREG(), KVM_REG_ARM64_SVE_PREG() or
3530                 KVM_REG_ARM64_SVE_FFR;           3530                 KVM_REG_ARM64_SVE_FFR;
3531                                                  3531 
3532               - KVM_REG_ARM64_SVE_VLS may opt    3532               - KVM_REG_ARM64_SVE_VLS may optionally be written using
3533                 KVM_SET_ONE_REG, to modify th    3533                 KVM_SET_ONE_REG, to modify the set of vector lengths available
3534                 for the vcpu.                    3534                 for the vcpu.
3535                                                  3535 
3536            * After KVM_ARM_VCPU_FINALIZE(KVM_    3536            * After KVM_ARM_VCPU_FINALIZE(KVM_ARM_VCPU_SVE):
3537                                                  3537 
3538               - the KVM_REG_ARM64_SVE_VLS pse    3538               - the KVM_REG_ARM64_SVE_VLS pseudo-register is immutable, and can
3539                 no longer be written using KV    3539                 no longer be written using KVM_SET_ONE_REG.
3540                                                  3540 
3541 4.83 KVM_ARM_PREFERRED_TARGET                    3541 4.83 KVM_ARM_PREFERRED_TARGET
3542 -----------------------------                    3542 -----------------------------
3543                                                  3543 
3544 :Capability: basic                               3544 :Capability: basic
3545 :Architectures: arm64                            3545 :Architectures: arm64
3546 :Type: vm ioctl                                  3546 :Type: vm ioctl
3547 :Parameters: struct kvm_vcpu_init (out)          3547 :Parameters: struct kvm_vcpu_init (out)
3548 :Returns: 0 on success; -1 on error              3548 :Returns: 0 on success; -1 on error
3549                                                  3549 
3550 Errors:                                          3550 Errors:
3551                                                  3551 
3552   ======     ================================    3552   ======     ==========================================
3553   ENODEV     no preferred target available fo    3553   ENODEV     no preferred target available for the host
3554   ======     ================================    3554   ======     ==========================================
3555                                                  3555 
3556 This queries KVM for preferred CPU target typ    3556 This queries KVM for preferred CPU target type which can be emulated
3557 by KVM on underlying host.                       3557 by KVM on underlying host.
3558                                                  3558 
3559 The ioctl returns struct kvm_vcpu_init instan    3559 The ioctl returns struct kvm_vcpu_init instance containing information
3560 about preferred CPU target type and recommend    3560 about preferred CPU target type and recommended features for it.  The
3561 kvm_vcpu_init->features bitmap returned will     3561 kvm_vcpu_init->features bitmap returned will have feature bits set if
3562 the preferred target recommends setting these    3562 the preferred target recommends setting these features, but this is
3563 not mandatory.                                   3563 not mandatory.
3564                                                  3564 
3565 The information returned by this ioctl can be    3565 The information returned by this ioctl can be used to prepare an instance
3566 of struct kvm_vcpu_init for KVM_ARM_VCPU_INIT    3566 of struct kvm_vcpu_init for KVM_ARM_VCPU_INIT ioctl which will result in
3567 VCPU matching underlying host.                   3567 VCPU matching underlying host.
3568                                                  3568 
3569                                                  3569 
3570 4.84 KVM_GET_REG_LIST                            3570 4.84 KVM_GET_REG_LIST
3571 ---------------------                            3571 ---------------------
3572                                                  3572 
3573 :Capability: basic                               3573 :Capability: basic
3574 :Architectures: arm64, mips, riscv               3574 :Architectures: arm64, mips, riscv
3575 :Type: vcpu ioctl                                3575 :Type: vcpu ioctl
3576 :Parameters: struct kvm_reg_list (in/out)        3576 :Parameters: struct kvm_reg_list (in/out)
3577 :Returns: 0 on success; -1 on error              3577 :Returns: 0 on success; -1 on error
3578                                                  3578 
3579 Errors:                                          3579 Errors:
3580                                                  3580 
3581   =====      ================================    3581   =====      ==============================================================
3582   E2BIG      the reg index list is too big to    3582   E2BIG      the reg index list is too big to fit in the array specified by
3583              the user (the number required wi    3583              the user (the number required will be written into n).
3584   =====      ================================    3584   =====      ==============================================================
3585                                                  3585 
3586 ::                                               3586 ::
3587                                                  3587 
3588   struct kvm_reg_list {                          3588   struct kvm_reg_list {
3589         __u64 n; /* number of registers in re    3589         __u64 n; /* number of registers in reg[] */
3590         __u64 reg[0];                            3590         __u64 reg[0];
3591   };                                             3591   };
3592                                                  3592 
3593 This ioctl returns the guest registers that a    3593 This ioctl returns the guest registers that are supported for the
3594 KVM_GET_ONE_REG/KVM_SET_ONE_REG calls.           3594 KVM_GET_ONE_REG/KVM_SET_ONE_REG calls.
3595                                                  3595 
3596                                                  3596 
3597 4.85 KVM_ARM_SET_DEVICE_ADDR (deprecated)        3597 4.85 KVM_ARM_SET_DEVICE_ADDR (deprecated)
3598 -----------------------------------------        3598 -----------------------------------------
3599                                                  3599 
3600 :Capability: KVM_CAP_ARM_SET_DEVICE_ADDR         3600 :Capability: KVM_CAP_ARM_SET_DEVICE_ADDR
3601 :Architectures: arm64                            3601 :Architectures: arm64
3602 :Type: vm ioctl                                  3602 :Type: vm ioctl
3603 :Parameters: struct kvm_arm_device_address (i    3603 :Parameters: struct kvm_arm_device_address (in)
3604 :Returns: 0 on success, -1 on error              3604 :Returns: 0 on success, -1 on error
3605                                                  3605 
3606 Errors:                                          3606 Errors:
3607                                                  3607 
3608   ======  ===================================    3608   ======  ============================================
3609   ENODEV  The device id is unknown               3609   ENODEV  The device id is unknown
3610   ENXIO   Device not supported on current sys    3610   ENXIO   Device not supported on current system
3611   EEXIST  Address already set                    3611   EEXIST  Address already set
3612   E2BIG   Address outside guest physical addr    3612   E2BIG   Address outside guest physical address space
3613   EBUSY   Address overlaps with other device     3613   EBUSY   Address overlaps with other device range
3614   ======  ===================================    3614   ======  ============================================
3615                                                  3615 
3616 ::                                               3616 ::
3617                                                  3617 
3618   struct kvm_arm_device_addr {                   3618   struct kvm_arm_device_addr {
3619         __u64 id;                                3619         __u64 id;
3620         __u64 addr;                              3620         __u64 addr;
3621   };                                             3621   };
3622                                                  3622 
3623 Specify a device address in the guest's physi    3623 Specify a device address in the guest's physical address space where guests
3624 can access emulated or directly exposed devic    3624 can access emulated or directly exposed devices, which the host kernel needs
3625 to know about. The id field is an architectur    3625 to know about. The id field is an architecture specific identifier for a
3626 specific device.                                 3626 specific device.
3627                                                  3627 
3628 arm64 divides the id field into two parts, a     3628 arm64 divides the id field into two parts, a device id and an
3629 address type id specific to the individual de    3629 address type id specific to the individual device::
3630                                                  3630 
3631   bits:  | 63        ...       32 | 31    ...    3631   bits:  | 63        ...       32 | 31    ...    16 | 15    ...    0 |
3632   field: |        0x00000000      |     devic    3632   field: |        0x00000000      |     device id   |  addr type id  |
3633                                                  3633 
3634 arm64 currently only require this when using     3634 arm64 currently only require this when using the in-kernel GIC
3635 support for the hardware VGIC features, using    3635 support for the hardware VGIC features, using KVM_ARM_DEVICE_VGIC_V2
3636 as the device id.  When setting the base addr    3636 as the device id.  When setting the base address for the guest's
3637 mapping of the VGIC virtual CPU and distribut    3637 mapping of the VGIC virtual CPU and distributor interface, the ioctl
3638 must be called after calling KVM_CREATE_IRQCH    3638 must be called after calling KVM_CREATE_IRQCHIP, but before calling
3639 KVM_RUN on any of the VCPUs.  Calling this io    3639 KVM_RUN on any of the VCPUs.  Calling this ioctl twice for any of the
3640 base addresses will return -EEXIST.              3640 base addresses will return -EEXIST.
3641                                                  3641 
3642 Note, this IOCTL is deprecated and the more f    3642 Note, this IOCTL is deprecated and the more flexible SET/GET_DEVICE_ATTR API
3643 should be used instead.                          3643 should be used instead.
3644                                                  3644 
3645                                                  3645 
3646 4.86 KVM_PPC_RTAS_DEFINE_TOKEN                   3646 4.86 KVM_PPC_RTAS_DEFINE_TOKEN
3647 ------------------------------                   3647 ------------------------------
3648                                                  3648 
3649 :Capability: KVM_CAP_PPC_RTAS                    3649 :Capability: KVM_CAP_PPC_RTAS
3650 :Architectures: ppc                              3650 :Architectures: ppc
3651 :Type: vm ioctl                                  3651 :Type: vm ioctl
3652 :Parameters: struct kvm_rtas_token_args          3652 :Parameters: struct kvm_rtas_token_args
3653 :Returns: 0 on success, -1 on error              3653 :Returns: 0 on success, -1 on error
3654                                                  3654 
3655 Defines a token value for a RTAS (Run Time Ab    3655 Defines a token value for a RTAS (Run Time Abstraction Services)
3656 service in order to allow it to be handled in    3656 service in order to allow it to be handled in the kernel.  The
3657 argument struct gives the name of the service    3657 argument struct gives the name of the service, which must be the name
3658 of a service that has a kernel-side implement    3658 of a service that has a kernel-side implementation.  If the token
3659 value is non-zero, it will be associated with    3659 value is non-zero, it will be associated with that service, and
3660 subsequent RTAS calls by the guest specifying    3660 subsequent RTAS calls by the guest specifying that token will be
3661 handled by the kernel.  If the token value is    3661 handled by the kernel.  If the token value is 0, then any token
3662 associated with the service will be forgotten    3662 associated with the service will be forgotten, and subsequent RTAS
3663 calls by the guest for that service will be p    3663 calls by the guest for that service will be passed to userspace to be
3664 handled.                                         3664 handled.
3665                                                  3665 
3666 4.87 KVM_SET_GUEST_DEBUG                         3666 4.87 KVM_SET_GUEST_DEBUG
3667 ------------------------                         3667 ------------------------
3668                                                  3668 
3669 :Capability: KVM_CAP_SET_GUEST_DEBUG             3669 :Capability: KVM_CAP_SET_GUEST_DEBUG
3670 :Architectures: x86, s390, ppc, arm64            3670 :Architectures: x86, s390, ppc, arm64
3671 :Type: vcpu ioctl                                3671 :Type: vcpu ioctl
3672 :Parameters: struct kvm_guest_debug (in)         3672 :Parameters: struct kvm_guest_debug (in)
3673 :Returns: 0 on success; -1 on error              3673 :Returns: 0 on success; -1 on error
3674                                                  3674 
3675 ::                                               3675 ::
3676                                                  3676 
3677   struct kvm_guest_debug {                       3677   struct kvm_guest_debug {
3678        __u32 control;                            3678        __u32 control;
3679        __u32 pad;                                3679        __u32 pad;
3680        struct kvm_guest_debug_arch arch;         3680        struct kvm_guest_debug_arch arch;
3681   };                                             3681   };
3682                                                  3682 
3683 Set up the processor specific debug registers    3683 Set up the processor specific debug registers and configure vcpu for
3684 handling guest debug events. There are two pa    3684 handling guest debug events. There are two parts to the structure, the
3685 first a control bitfield indicates the type o    3685 first a control bitfield indicates the type of debug events to handle
3686 when running. Common control bits are:           3686 when running. Common control bits are:
3687                                                  3687 
3688   - KVM_GUESTDBG_ENABLE:        guest debuggi    3688   - KVM_GUESTDBG_ENABLE:        guest debugging is enabled
3689   - KVM_GUESTDBG_SINGLESTEP:    the next run     3689   - KVM_GUESTDBG_SINGLESTEP:    the next run should single-step
3690                                                  3690 
3691 The top 16 bits of the control field are arch    3691 The top 16 bits of the control field are architecture specific control
3692 flags which can include the following:           3692 flags which can include the following:
3693                                                  3693 
3694   - KVM_GUESTDBG_USE_SW_BP:     using softwar    3694   - KVM_GUESTDBG_USE_SW_BP:     using software breakpoints [x86, arm64]
3695   - KVM_GUESTDBG_USE_HW_BP:     using hardwar    3695   - KVM_GUESTDBG_USE_HW_BP:     using hardware breakpoints [x86, s390]
3696   - KVM_GUESTDBG_USE_HW:        using hardwar    3696   - KVM_GUESTDBG_USE_HW:        using hardware debug events [arm64]
3697   - KVM_GUESTDBG_INJECT_DB:     inject DB typ    3697   - KVM_GUESTDBG_INJECT_DB:     inject DB type exception [x86]
3698   - KVM_GUESTDBG_INJECT_BP:     inject BP typ    3698   - KVM_GUESTDBG_INJECT_BP:     inject BP type exception [x86]
3699   - KVM_GUESTDBG_EXIT_PENDING:  trigger an im    3699   - KVM_GUESTDBG_EXIT_PENDING:  trigger an immediate guest exit [s390]
3700   - KVM_GUESTDBG_BLOCKIRQ:      avoid injecti    3700   - KVM_GUESTDBG_BLOCKIRQ:      avoid injecting interrupts/NMI/SMI [x86]
3701                                                  3701 
3702 For example KVM_GUESTDBG_USE_SW_BP indicates     3702 For example KVM_GUESTDBG_USE_SW_BP indicates that software breakpoints
3703 are enabled in memory so we need to ensure br    3703 are enabled in memory so we need to ensure breakpoint exceptions are
3704 correctly trapped and the KVM run loop exits     3704 correctly trapped and the KVM run loop exits at the breakpoint and not
3705 running off into the normal guest vector. For    3705 running off into the normal guest vector. For KVM_GUESTDBG_USE_HW_BP
3706 we need to ensure the guest vCPUs architectur    3706 we need to ensure the guest vCPUs architecture specific registers are
3707 updated to the correct (supplied) values.        3707 updated to the correct (supplied) values.
3708                                                  3708 
3709 The second part of the structure is architect    3709 The second part of the structure is architecture specific and
3710 typically contains a set of debug registers.     3710 typically contains a set of debug registers.
3711                                                  3711 
3712 For arm64 the number of debug registers is im    3712 For arm64 the number of debug registers is implementation defined and
3713 can be determined by querying the KVM_CAP_GUE    3713 can be determined by querying the KVM_CAP_GUEST_DEBUG_HW_BPS and
3714 KVM_CAP_GUEST_DEBUG_HW_WPS capabilities which    3714 KVM_CAP_GUEST_DEBUG_HW_WPS capabilities which return a positive number
3715 indicating the number of supported registers.    3715 indicating the number of supported registers.
3716                                                  3716 
3717 For ppc, the KVM_CAP_PPC_GUEST_DEBUG_SSTEP ca    3717 For ppc, the KVM_CAP_PPC_GUEST_DEBUG_SSTEP capability indicates whether
3718 the single-step debug event (KVM_GUESTDBG_SIN    3718 the single-step debug event (KVM_GUESTDBG_SINGLESTEP) is supported.
3719                                                  3719 
3720 Also when supported, KVM_CAP_SET_GUEST_DEBUG2    3720 Also when supported, KVM_CAP_SET_GUEST_DEBUG2 capability indicates the
3721 supported KVM_GUESTDBG_* bits in the control     3721 supported KVM_GUESTDBG_* bits in the control field.
3722                                                  3722 
3723 When debug events exit the main run loop with    3723 When debug events exit the main run loop with the reason
3724 KVM_EXIT_DEBUG with the kvm_debug_exit_arch p    3724 KVM_EXIT_DEBUG with the kvm_debug_exit_arch part of the kvm_run
3725 structure containing architecture specific de    3725 structure containing architecture specific debug information.
3726                                                  3726 
3727 4.88 KVM_GET_EMULATED_CPUID                      3727 4.88 KVM_GET_EMULATED_CPUID
3728 ---------------------------                      3728 ---------------------------
3729                                                  3729 
3730 :Capability: KVM_CAP_EXT_EMUL_CPUID              3730 :Capability: KVM_CAP_EXT_EMUL_CPUID
3731 :Architectures: x86                              3731 :Architectures: x86
3732 :Type: system ioctl                              3732 :Type: system ioctl
3733 :Parameters: struct kvm_cpuid2 (in/out)          3733 :Parameters: struct kvm_cpuid2 (in/out)
3734 :Returns: 0 on success, -1 on error              3734 :Returns: 0 on success, -1 on error
3735                                                  3735 
3736 ::                                               3736 ::
3737                                                  3737 
3738   struct kvm_cpuid2 {                            3738   struct kvm_cpuid2 {
3739         __u32 nent;                              3739         __u32 nent;
3740         __u32 flags;                             3740         __u32 flags;
3741         struct kvm_cpuid_entry2 entries[0];      3741         struct kvm_cpuid_entry2 entries[0];
3742   };                                             3742   };
3743                                                  3743 
3744 The member 'flags' is used for passing flags     3744 The member 'flags' is used for passing flags from userspace.
3745                                                  3745 
3746 ::                                               3746 ::
3747                                                  3747 
3748   #define KVM_CPUID_FLAG_SIGNIFCANT_INDEX        3748   #define KVM_CPUID_FLAG_SIGNIFCANT_INDEX               BIT(0)
3749   #define KVM_CPUID_FLAG_STATEFUL_FUNC           3749   #define KVM_CPUID_FLAG_STATEFUL_FUNC          BIT(1) /* deprecated */
3750   #define KVM_CPUID_FLAG_STATE_READ_NEXT         3750   #define KVM_CPUID_FLAG_STATE_READ_NEXT                BIT(2) /* deprecated */
3751                                                  3751 
3752   struct kvm_cpuid_entry2 {                      3752   struct kvm_cpuid_entry2 {
3753         __u32 function;                          3753         __u32 function;
3754         __u32 index;                             3754         __u32 index;
3755         __u32 flags;                             3755         __u32 flags;
3756         __u32 eax;                               3756         __u32 eax;
3757         __u32 ebx;                               3757         __u32 ebx;
3758         __u32 ecx;                               3758         __u32 ecx;
3759         __u32 edx;                               3759         __u32 edx;
3760         __u32 padding[3];                        3760         __u32 padding[3];
3761   };                                             3761   };
3762                                                  3762 
3763 This ioctl returns x86 cpuid features which a    3763 This ioctl returns x86 cpuid features which are emulated by
3764 kvm.Userspace can use the information returne    3764 kvm.Userspace can use the information returned by this ioctl to query
3765 which features are emulated by kvm instead of    3765 which features are emulated by kvm instead of being present natively.
3766                                                  3766 
3767 Userspace invokes KVM_GET_EMULATED_CPUID by p    3767 Userspace invokes KVM_GET_EMULATED_CPUID by passing a kvm_cpuid2
3768 structure with the 'nent' field indicating th    3768 structure with the 'nent' field indicating the number of entries in
3769 the variable-size array 'entries'. If the num    3769 the variable-size array 'entries'. If the number of entries is too low
3770 to describe the cpu capabilities, an error (E    3770 to describe the cpu capabilities, an error (E2BIG) is returned. If the
3771 number is too high, the 'nent' field is adjus    3771 number is too high, the 'nent' field is adjusted and an error (ENOMEM)
3772 is returned. If the number is just right, the    3772 is returned. If the number is just right, the 'nent' field is adjusted
3773 to the number of valid entries in the 'entrie    3773 to the number of valid entries in the 'entries' array, which is then
3774 filled.                                          3774 filled.
3775                                                  3775 
3776 The entries returned are the set CPUID bits o    3776 The entries returned are the set CPUID bits of the respective features
3777 which kvm emulates, as returned by the CPUID     3777 which kvm emulates, as returned by the CPUID instruction, with unknown
3778 or unsupported feature bits cleared.             3778 or unsupported feature bits cleared.
3779                                                  3779 
3780 Features like x2apic, for example, may not be    3780 Features like x2apic, for example, may not be present in the host cpu
3781 but are exposed by kvm in KVM_GET_SUPPORTED_C    3781 but are exposed by kvm in KVM_GET_SUPPORTED_CPUID because they can be
3782 emulated efficiently and thus not included he    3782 emulated efficiently and thus not included here.
3783                                                  3783 
3784 The fields in each entry are defined as follo    3784 The fields in each entry are defined as follows:
3785                                                  3785 
3786   function:                                      3786   function:
3787          the eax value used to obtain the ent    3787          the eax value used to obtain the entry
3788   index:                                         3788   index:
3789          the ecx value used to obtain the ent    3789          the ecx value used to obtain the entry (for entries that are
3790          affected by ecx)                        3790          affected by ecx)
3791   flags:                                         3791   flags:
3792     an OR of zero or more of the following:      3792     an OR of zero or more of the following:
3793                                                  3793 
3794         KVM_CPUID_FLAG_SIGNIFCANT_INDEX:         3794         KVM_CPUID_FLAG_SIGNIFCANT_INDEX:
3795            if the index field is valid           3795            if the index field is valid
3796                                                  3796 
3797    eax, ebx, ecx, edx:                           3797    eax, ebx, ecx, edx:
3798                                                  3798 
3799          the values returned by the cpuid ins    3799          the values returned by the cpuid instruction for
3800          this function/index combination         3800          this function/index combination
3801                                                  3801 
3802 4.89 KVM_S390_MEM_OP                             3802 4.89 KVM_S390_MEM_OP
3803 --------------------                             3803 --------------------
3804                                                  3804 
3805 :Capability: KVM_CAP_S390_MEM_OP, KVM_CAP_S39    3805 :Capability: KVM_CAP_S390_MEM_OP, KVM_CAP_S390_PROTECTED, KVM_CAP_S390_MEM_OP_EXTENSION
3806 :Architectures: s390                             3806 :Architectures: s390
3807 :Type: vm ioctl, vcpu ioctl                      3807 :Type: vm ioctl, vcpu ioctl
3808 :Parameters: struct kvm_s390_mem_op (in)         3808 :Parameters: struct kvm_s390_mem_op (in)
3809 :Returns: = 0 on success,                        3809 :Returns: = 0 on success,
3810           < 0 on generic error (e.g. -EFAULT     3810           < 0 on generic error (e.g. -EFAULT or -ENOMEM),
3811           16 bit program exception code if th    3811           16 bit program exception code if the access causes such an exception
3812                                                  3812 
3813 Read or write data from/to the VM's memory.      3813 Read or write data from/to the VM's memory.
3814 The KVM_CAP_S390_MEM_OP_EXTENSION capability     3814 The KVM_CAP_S390_MEM_OP_EXTENSION capability specifies what functionality is
3815 supported.                                       3815 supported.
3816                                                  3816 
3817 Parameters are specified via the following st    3817 Parameters are specified via the following structure::
3818                                                  3818 
3819   struct kvm_s390_mem_op {                       3819   struct kvm_s390_mem_op {
3820         __u64 gaddr;            /* the guest     3820         __u64 gaddr;            /* the guest address */
3821         __u64 flags;            /* flags */      3821         __u64 flags;            /* flags */
3822         __u32 size;             /* amount of     3822         __u32 size;             /* amount of bytes */
3823         __u32 op;               /* type of op    3823         __u32 op;               /* type of operation */
3824         __u64 buf;              /* buffer in     3824         __u64 buf;              /* buffer in userspace */
3825         union {                                  3825         union {
3826                 struct {                         3826                 struct {
3827                         __u8 ar;        /* th    3827                         __u8 ar;        /* the access register number */
3828                         __u8 key;       /* ac    3828                         __u8 key;       /* access key, ignored if flag unset */
3829                         __u8 pad1[6];   /* ig    3829                         __u8 pad1[6];   /* ignored */
3830                         __u64 old_addr; /* ig    3830                         __u64 old_addr; /* ignored if flag unset */
3831                 };                               3831                 };
3832                 __u32 sida_offset; /* offset     3832                 __u32 sida_offset; /* offset into the sida */
3833                 __u8 reserved[32]; /* ignored    3833                 __u8 reserved[32]; /* ignored */
3834         };                                       3834         };
3835   };                                             3835   };
3836                                                  3836 
3837 The start address of the memory region has to    3837 The start address of the memory region has to be specified in the "gaddr"
3838 field, and the length of the region in the "s    3838 field, and the length of the region in the "size" field (which must not
3839 be 0). The maximum value for "size" can be ob    3839 be 0). The maximum value for "size" can be obtained by checking the
3840 KVM_CAP_S390_MEM_OP capability. "buf" is the     3840 KVM_CAP_S390_MEM_OP capability. "buf" is the buffer supplied by the
3841 userspace application where the read data sho    3841 userspace application where the read data should be written to for
3842 a read access, or where the data that should     3842 a read access, or where the data that should be written is stored for
3843 a write access.  The "reserved" field is mean    3843 a write access.  The "reserved" field is meant for future extensions.
3844 Reserved and unused values are ignored. Futur    3844 Reserved and unused values are ignored. Future extension that add members must
3845 introduce new flags.                             3845 introduce new flags.
3846                                                  3846 
3847 The type of operation is specified in the "op    3847 The type of operation is specified in the "op" field. Flags modifying
3848 their behavior can be set in the "flags" fiel    3848 their behavior can be set in the "flags" field. Undefined flag bits must
3849 be set to 0.                                     3849 be set to 0.
3850                                                  3850 
3851 Possible operations are:                         3851 Possible operations are:
3852   * ``KVM_S390_MEMOP_LOGICAL_READ``              3852   * ``KVM_S390_MEMOP_LOGICAL_READ``
3853   * ``KVM_S390_MEMOP_LOGICAL_WRITE``             3853   * ``KVM_S390_MEMOP_LOGICAL_WRITE``
3854   * ``KVM_S390_MEMOP_ABSOLUTE_READ``             3854   * ``KVM_S390_MEMOP_ABSOLUTE_READ``
3855   * ``KVM_S390_MEMOP_ABSOLUTE_WRITE``            3855   * ``KVM_S390_MEMOP_ABSOLUTE_WRITE``
3856   * ``KVM_S390_MEMOP_SIDA_READ``                 3856   * ``KVM_S390_MEMOP_SIDA_READ``
3857   * ``KVM_S390_MEMOP_SIDA_WRITE``                3857   * ``KVM_S390_MEMOP_SIDA_WRITE``
3858   * ``KVM_S390_MEMOP_ABSOLUTE_CMPXCHG``          3858   * ``KVM_S390_MEMOP_ABSOLUTE_CMPXCHG``
3859                                                  3859 
3860 Logical read/write:                              3860 Logical read/write:
3861 ^^^^^^^^^^^^^^^^^^^                              3861 ^^^^^^^^^^^^^^^^^^^
3862                                                  3862 
3863 Access logical memory, i.e. translate the giv    3863 Access logical memory, i.e. translate the given guest address to an absolute
3864 address given the state of the VCPU and use t    3864 address given the state of the VCPU and use the absolute address as target of
3865 the access. "ar" designates the access regist    3865 the access. "ar" designates the access register number to be used; the valid
3866 range is 0..15.                                  3866 range is 0..15.
3867 Logical accesses are permitted for the VCPU i    3867 Logical accesses are permitted for the VCPU ioctl only.
3868 Logical accesses are permitted for non-protec    3868 Logical accesses are permitted for non-protected guests only.
3869                                                  3869 
3870 Supported flags:                                 3870 Supported flags:
3871   * ``KVM_S390_MEMOP_F_CHECK_ONLY``              3871   * ``KVM_S390_MEMOP_F_CHECK_ONLY``
3872   * ``KVM_S390_MEMOP_F_INJECT_EXCEPTION``        3872   * ``KVM_S390_MEMOP_F_INJECT_EXCEPTION``
3873   * ``KVM_S390_MEMOP_F_SKEY_PROTECTION``         3873   * ``KVM_S390_MEMOP_F_SKEY_PROTECTION``
3874                                                  3874 
3875 The KVM_S390_MEMOP_F_CHECK_ONLY flag can be s    3875 The KVM_S390_MEMOP_F_CHECK_ONLY flag can be set to check whether the
3876 corresponding memory access would cause an ac    3876 corresponding memory access would cause an access exception; however,
3877 no actual access to the data in memory at the    3877 no actual access to the data in memory at the destination is performed.
3878 In this case, "buf" is unused and can be NULL    3878 In this case, "buf" is unused and can be NULL.
3879                                                  3879 
3880 In case an access exception occurred during t    3880 In case an access exception occurred during the access (or would occur
3881 in case of KVM_S390_MEMOP_F_CHECK_ONLY), the     3881 in case of KVM_S390_MEMOP_F_CHECK_ONLY), the ioctl returns a positive
3882 error number indicating the type of exception    3882 error number indicating the type of exception. This exception is also
3883 raised directly at the corresponding VCPU if     3883 raised directly at the corresponding VCPU if the flag
3884 KVM_S390_MEMOP_F_INJECT_EXCEPTION is set.        3884 KVM_S390_MEMOP_F_INJECT_EXCEPTION is set.
3885 On protection exceptions, unless specified ot    3885 On protection exceptions, unless specified otherwise, the injected
3886 translation-exception identifier (TEID) indic    3886 translation-exception identifier (TEID) indicates suppression.
3887                                                  3887 
3888 If the KVM_S390_MEMOP_F_SKEY_PROTECTION flag     3888 If the KVM_S390_MEMOP_F_SKEY_PROTECTION flag is set, storage key
3889 protection is also in effect and may cause ex    3889 protection is also in effect and may cause exceptions if accesses are
3890 prohibited given the access key designated by    3890 prohibited given the access key designated by "key"; the valid range is 0..15.
3891 KVM_S390_MEMOP_F_SKEY_PROTECTION is available    3891 KVM_S390_MEMOP_F_SKEY_PROTECTION is available if KVM_CAP_S390_MEM_OP_EXTENSION
3892 is > 0.                                          3892 is > 0.
3893 Since the accessed memory may span multiple p    3893 Since the accessed memory may span multiple pages and those pages might have
3894 different storage keys, it is possible that a    3894 different storage keys, it is possible that a protection exception occurs
3895 after memory has been modified. In this case,    3895 after memory has been modified. In this case, if the exception is injected,
3896 the TEID does not indicate suppression.          3896 the TEID does not indicate suppression.
3897                                                  3897 
3898 Absolute read/write:                             3898 Absolute read/write:
3899 ^^^^^^^^^^^^^^^^^^^^                             3899 ^^^^^^^^^^^^^^^^^^^^
3900                                                  3900 
3901 Access absolute memory. This operation is int    3901 Access absolute memory. This operation is intended to be used with the
3902 KVM_S390_MEMOP_F_SKEY_PROTECTION flag, to all    3902 KVM_S390_MEMOP_F_SKEY_PROTECTION flag, to allow accessing memory and performing
3903 the checks required for storage key protectio    3903 the checks required for storage key protection as one operation (as opposed to
3904 user space getting the storage keys, performi    3904 user space getting the storage keys, performing the checks, and accessing
3905 memory thereafter, which could lead to a dela    3905 memory thereafter, which could lead to a delay between check and access).
3906 Absolute accesses are permitted for the VM io    3906 Absolute accesses are permitted for the VM ioctl if KVM_CAP_S390_MEM_OP_EXTENSION
3907 has the KVM_S390_MEMOP_EXTENSION_CAP_BASE bit    3907 has the KVM_S390_MEMOP_EXTENSION_CAP_BASE bit set.
3908 Currently absolute accesses are not permitted    3908 Currently absolute accesses are not permitted for VCPU ioctls.
3909 Absolute accesses are permitted for non-prote    3909 Absolute accesses are permitted for non-protected guests only.
3910                                                  3910 
3911 Supported flags:                                 3911 Supported flags:
3912   * ``KVM_S390_MEMOP_F_CHECK_ONLY``              3912   * ``KVM_S390_MEMOP_F_CHECK_ONLY``
3913   * ``KVM_S390_MEMOP_F_SKEY_PROTECTION``         3913   * ``KVM_S390_MEMOP_F_SKEY_PROTECTION``
3914                                                  3914 
3915 The semantics of the flags common with logica    3915 The semantics of the flags common with logical accesses are as for logical
3916 accesses.                                        3916 accesses.
3917                                                  3917 
3918 Absolute cmpxchg:                                3918 Absolute cmpxchg:
3919 ^^^^^^^^^^^^^^^^^                                3919 ^^^^^^^^^^^^^^^^^
3920                                                  3920 
3921 Perform cmpxchg on absolute guest memory. Int    3921 Perform cmpxchg on absolute guest memory. Intended for use with the
3922 KVM_S390_MEMOP_F_SKEY_PROTECTION flag.           3922 KVM_S390_MEMOP_F_SKEY_PROTECTION flag.
3923 Instead of doing an unconditional write, the     3923 Instead of doing an unconditional write, the access occurs only if the target
3924 location contains the value pointed to by "ol    3924 location contains the value pointed to by "old_addr".
3925 This is performed as an atomic cmpxchg with t    3925 This is performed as an atomic cmpxchg with the length specified by the "size"
3926 parameter. "size" must be a power of two up t    3926 parameter. "size" must be a power of two up to and including 16.
3927 If the exchange did not take place because th    3927 If the exchange did not take place because the target value doesn't match the
3928 old value, the value "old_addr" points to is     3928 old value, the value "old_addr" points to is replaced by the target value.
3929 User space can tell if an exchange took place    3929 User space can tell if an exchange took place by checking if this replacement
3930 occurred. The cmpxchg op is permitted for the    3930 occurred. The cmpxchg op is permitted for the VM ioctl if
3931 KVM_CAP_S390_MEM_OP_EXTENSION has flag KVM_S3    3931 KVM_CAP_S390_MEM_OP_EXTENSION has flag KVM_S390_MEMOP_EXTENSION_CAP_CMPXCHG set.
3932                                                  3932 
3933 Supported flags:                                 3933 Supported flags:
3934   * ``KVM_S390_MEMOP_F_SKEY_PROTECTION``         3934   * ``KVM_S390_MEMOP_F_SKEY_PROTECTION``
3935                                                  3935 
3936 SIDA read/write:                                 3936 SIDA read/write:
3937 ^^^^^^^^^^^^^^^^                                 3937 ^^^^^^^^^^^^^^^^
3938                                                  3938 
3939 Access the secure instruction data area which    3939 Access the secure instruction data area which contains memory operands necessary
3940 for instruction emulation for protected guest    3940 for instruction emulation for protected guests.
3941 SIDA accesses are available if the KVM_CAP_S3    3941 SIDA accesses are available if the KVM_CAP_S390_PROTECTED capability is available.
3942 SIDA accesses are permitted for the VCPU ioct    3942 SIDA accesses are permitted for the VCPU ioctl only.
3943 SIDA accesses are permitted for protected gue    3943 SIDA accesses are permitted for protected guests only.
3944                                                  3944 
3945 No flags are supported.                          3945 No flags are supported.
3946                                                  3946 
3947 4.90 KVM_S390_GET_SKEYS                          3947 4.90 KVM_S390_GET_SKEYS
3948 -----------------------                          3948 -----------------------
3949                                                  3949 
3950 :Capability: KVM_CAP_S390_SKEYS                  3950 :Capability: KVM_CAP_S390_SKEYS
3951 :Architectures: s390                             3951 :Architectures: s390
3952 :Type: vm ioctl                                  3952 :Type: vm ioctl
3953 :Parameters: struct kvm_s390_skeys               3953 :Parameters: struct kvm_s390_skeys
3954 :Returns: 0 on success, KVM_S390_GET_SKEYS_NO    3954 :Returns: 0 on success, KVM_S390_GET_SKEYS_NONE if guest is not using storage
3955           keys, negative value on error          3955           keys, negative value on error
3956                                                  3956 
3957 This ioctl is used to get guest storage key v    3957 This ioctl is used to get guest storage key values on the s390
3958 architecture. The ioctl takes parameters via     3958 architecture. The ioctl takes parameters via the kvm_s390_skeys struct::
3959                                                  3959 
3960   struct kvm_s390_skeys {                        3960   struct kvm_s390_skeys {
3961         __u64 start_gfn;                         3961         __u64 start_gfn;
3962         __u64 count;                             3962         __u64 count;
3963         __u64 skeydata_addr;                     3963         __u64 skeydata_addr;
3964         __u32 flags;                             3964         __u32 flags;
3965         __u32 reserved[9];                       3965         __u32 reserved[9];
3966   };                                             3966   };
3967                                                  3967 
3968 The start_gfn field is the number of the firs    3968 The start_gfn field is the number of the first guest frame whose storage keys
3969 you want to get.                                 3969 you want to get.
3970                                                  3970 
3971 The count field is the number of consecutive     3971 The count field is the number of consecutive frames (starting from start_gfn)
3972 whose storage keys to get. The count field mu    3972 whose storage keys to get. The count field must be at least 1 and the maximum
3973 allowed value is defined as KVM_S390_SKEYS_MA    3973 allowed value is defined as KVM_S390_SKEYS_MAX. Values outside this range
3974 will cause the ioctl to return -EINVAL.          3974 will cause the ioctl to return -EINVAL.
3975                                                  3975 
3976 The skeydata_addr field is the address to a b    3976 The skeydata_addr field is the address to a buffer large enough to hold count
3977 bytes. This buffer will be filled with storag    3977 bytes. This buffer will be filled with storage key data by the ioctl.
3978                                                  3978 
3979 4.91 KVM_S390_SET_SKEYS                          3979 4.91 KVM_S390_SET_SKEYS
3980 -----------------------                          3980 -----------------------
3981                                                  3981 
3982 :Capability: KVM_CAP_S390_SKEYS                  3982 :Capability: KVM_CAP_S390_SKEYS
3983 :Architectures: s390                             3983 :Architectures: s390
3984 :Type: vm ioctl                                  3984 :Type: vm ioctl
3985 :Parameters: struct kvm_s390_skeys               3985 :Parameters: struct kvm_s390_skeys
3986 :Returns: 0 on success, negative value on err    3986 :Returns: 0 on success, negative value on error
3987                                                  3987 
3988 This ioctl is used to set guest storage key v    3988 This ioctl is used to set guest storage key values on the s390
3989 architecture. The ioctl takes parameters via     3989 architecture. The ioctl takes parameters via the kvm_s390_skeys struct.
3990 See section on KVM_S390_GET_SKEYS for struct     3990 See section on KVM_S390_GET_SKEYS for struct definition.
3991                                                  3991 
3992 The start_gfn field is the number of the firs    3992 The start_gfn field is the number of the first guest frame whose storage keys
3993 you want to set.                                 3993 you want to set.
3994                                                  3994 
3995 The count field is the number of consecutive     3995 The count field is the number of consecutive frames (starting from start_gfn)
3996 whose storage keys to get. The count field mu    3996 whose storage keys to get. The count field must be at least 1 and the maximum
3997 allowed value is defined as KVM_S390_SKEYS_MA    3997 allowed value is defined as KVM_S390_SKEYS_MAX. Values outside this range
3998 will cause the ioctl to return -EINVAL.          3998 will cause the ioctl to return -EINVAL.
3999                                                  3999 
4000 The skeydata_addr field is the address to a b    4000 The skeydata_addr field is the address to a buffer containing count bytes of
4001 storage keys. Each byte in the buffer will be    4001 storage keys. Each byte in the buffer will be set as the storage key for a
4002 single frame starting at start_gfn for count     4002 single frame starting at start_gfn for count frames.
4003                                                  4003 
4004 Note: If any architecturally invalid key valu    4004 Note: If any architecturally invalid key value is found in the given data then
4005 the ioctl will return -EINVAL.                   4005 the ioctl will return -EINVAL.
4006                                                  4006 
4007 4.92 KVM_S390_IRQ                                4007 4.92 KVM_S390_IRQ
4008 -----------------                                4008 -----------------
4009                                                  4009 
4010 :Capability: KVM_CAP_S390_INJECT_IRQ             4010 :Capability: KVM_CAP_S390_INJECT_IRQ
4011 :Architectures: s390                             4011 :Architectures: s390
4012 :Type: vcpu ioctl                                4012 :Type: vcpu ioctl
4013 :Parameters: struct kvm_s390_irq (in)            4013 :Parameters: struct kvm_s390_irq (in)
4014 :Returns: 0 on success, -1 on error              4014 :Returns: 0 on success, -1 on error
4015                                                  4015 
4016 Errors:                                          4016 Errors:
4017                                                  4017 
4018                                                  4018 
4019   ======  ===================================    4019   ======  =================================================================
4020   EINVAL  interrupt type is invalid              4020   EINVAL  interrupt type is invalid
4021           type is KVM_S390_SIGP_STOP and flag    4021           type is KVM_S390_SIGP_STOP and flag parameter is invalid value,
4022           type is KVM_S390_INT_EXTERNAL_CALL     4022           type is KVM_S390_INT_EXTERNAL_CALL and code is bigger
4023           than the maximum of VCPUs              4023           than the maximum of VCPUs
4024   EBUSY   type is KVM_S390_SIGP_SET_PREFIX an    4024   EBUSY   type is KVM_S390_SIGP_SET_PREFIX and vcpu is not stopped,
4025           type is KVM_S390_SIGP_STOP and a st    4025           type is KVM_S390_SIGP_STOP and a stop irq is already pending,
4026           type is KVM_S390_INT_EXTERNAL_CALL     4026           type is KVM_S390_INT_EXTERNAL_CALL and an external call interrupt
4027           is already pending                     4027           is already pending
4028   ======  ===================================    4028   ======  =================================================================
4029                                                  4029 
4030 Allows to inject an interrupt to the guest.      4030 Allows to inject an interrupt to the guest.
4031                                                  4031 
4032 Using struct kvm_s390_irq as a parameter allo    4032 Using struct kvm_s390_irq as a parameter allows
4033 to inject additional payload which is not        4033 to inject additional payload which is not
4034 possible via KVM_S390_INTERRUPT.                 4034 possible via KVM_S390_INTERRUPT.
4035                                                  4035 
4036 Interrupt parameters are passed via kvm_s390_    4036 Interrupt parameters are passed via kvm_s390_irq::
4037                                                  4037 
4038   struct kvm_s390_irq {                          4038   struct kvm_s390_irq {
4039         __u64 type;                              4039         __u64 type;
4040         union {                                  4040         union {
4041                 struct kvm_s390_io_info io;      4041                 struct kvm_s390_io_info io;
4042                 struct kvm_s390_ext_info ext;    4042                 struct kvm_s390_ext_info ext;
4043                 struct kvm_s390_pgm_info pgm;    4043                 struct kvm_s390_pgm_info pgm;
4044                 struct kvm_s390_emerg_info em    4044                 struct kvm_s390_emerg_info emerg;
4045                 struct kvm_s390_extcall_info     4045                 struct kvm_s390_extcall_info extcall;
4046                 struct kvm_s390_prefix_info p    4046                 struct kvm_s390_prefix_info prefix;
4047                 struct kvm_s390_stop_info sto    4047                 struct kvm_s390_stop_info stop;
4048                 struct kvm_s390_mchk_info mch    4048                 struct kvm_s390_mchk_info mchk;
4049                 char reserved[64];               4049                 char reserved[64];
4050         } u;                                     4050         } u;
4051   };                                             4051   };
4052                                                  4052 
4053 type can be one of the following:                4053 type can be one of the following:
4054                                                  4054 
4055 - KVM_S390_SIGP_STOP - sigp stop; parameter i    4055 - KVM_S390_SIGP_STOP - sigp stop; parameter in .stop
4056 - KVM_S390_PROGRAM_INT - program check; param    4056 - KVM_S390_PROGRAM_INT - program check; parameters in .pgm
4057 - KVM_S390_SIGP_SET_PREFIX - sigp set prefix;    4057 - KVM_S390_SIGP_SET_PREFIX - sigp set prefix; parameters in .prefix
4058 - KVM_S390_RESTART - restart; no parameters      4058 - KVM_S390_RESTART - restart; no parameters
4059 - KVM_S390_INT_CLOCK_COMP - clock comparator     4059 - KVM_S390_INT_CLOCK_COMP - clock comparator interrupt; no parameters
4060 - KVM_S390_INT_CPU_TIMER - CPU timer interrup    4060 - KVM_S390_INT_CPU_TIMER - CPU timer interrupt; no parameters
4061 - KVM_S390_INT_EMERGENCY - sigp emergency; pa    4061 - KVM_S390_INT_EMERGENCY - sigp emergency; parameters in .emerg
4062 - KVM_S390_INT_EXTERNAL_CALL - sigp external     4062 - KVM_S390_INT_EXTERNAL_CALL - sigp external call; parameters in .extcall
4063 - KVM_S390_MCHK - machine check interrupt; pa    4063 - KVM_S390_MCHK - machine check interrupt; parameters in .mchk
4064                                                  4064 
4065 This is an asynchronous vcpu ioctl and can be    4065 This is an asynchronous vcpu ioctl and can be invoked from any thread.
4066                                                  4066 
4067 4.94 KVM_S390_GET_IRQ_STATE                      4067 4.94 KVM_S390_GET_IRQ_STATE
4068 ---------------------------                      4068 ---------------------------
4069                                                  4069 
4070 :Capability: KVM_CAP_S390_IRQ_STATE              4070 :Capability: KVM_CAP_S390_IRQ_STATE
4071 :Architectures: s390                             4071 :Architectures: s390
4072 :Type: vcpu ioctl                                4072 :Type: vcpu ioctl
4073 :Parameters: struct kvm_s390_irq_state (out)     4073 :Parameters: struct kvm_s390_irq_state (out)
4074 :Returns: >= number of bytes copied into buff    4074 :Returns: >= number of bytes copied into buffer,
4075           -EINVAL if buffer size is 0,           4075           -EINVAL if buffer size is 0,
4076           -ENOBUFS if buffer size is too smal    4076           -ENOBUFS if buffer size is too small to fit all pending interrupts,
4077           -EFAULT if the buffer address was i    4077           -EFAULT if the buffer address was invalid
4078                                                  4078 
4079 This ioctl allows userspace to retrieve the c    4079 This ioctl allows userspace to retrieve the complete state of all currently
4080 pending interrupts in a single buffer. Use ca    4080 pending interrupts in a single buffer. Use cases include migration
4081 and introspection. The parameter structure co    4081 and introspection. The parameter structure contains the address of a
4082 userspace buffer and its length::                4082 userspace buffer and its length::
4083                                                  4083 
4084   struct kvm_s390_irq_state {                    4084   struct kvm_s390_irq_state {
4085         __u64 buf;                               4085         __u64 buf;
4086         __u32 flags;        /* will stay unus    4086         __u32 flags;        /* will stay unused for compatibility reasons */
4087         __u32 len;                               4087         __u32 len;
4088         __u32 reserved[4];  /* will stay unus    4088         __u32 reserved[4];  /* will stay unused for compatibility reasons */
4089   };                                             4089   };
4090                                                  4090 
4091 Userspace passes in the above struct and for     4091 Userspace passes in the above struct and for each pending interrupt a
4092 struct kvm_s390_irq is copied to the provided    4092 struct kvm_s390_irq is copied to the provided buffer.
4093                                                  4093 
4094 The structure contains a flags and a reserved    4094 The structure contains a flags and a reserved field for future extensions. As
4095 the kernel never checked for flags == 0 and Q    4095 the kernel never checked for flags == 0 and QEMU never pre-zeroed flags and
4096 reserved, these fields can not be used in the    4096 reserved, these fields can not be used in the future without breaking
4097 compatibility.                                   4097 compatibility.
4098                                                  4098 
4099 If -ENOBUFS is returned the buffer provided w    4099 If -ENOBUFS is returned the buffer provided was too small and userspace
4100 may retry with a bigger buffer.                  4100 may retry with a bigger buffer.
4101                                                  4101 
4102 4.95 KVM_S390_SET_IRQ_STATE                      4102 4.95 KVM_S390_SET_IRQ_STATE
4103 ---------------------------                      4103 ---------------------------
4104                                                  4104 
4105 :Capability: KVM_CAP_S390_IRQ_STATE              4105 :Capability: KVM_CAP_S390_IRQ_STATE
4106 :Architectures: s390                             4106 :Architectures: s390
4107 :Type: vcpu ioctl                                4107 :Type: vcpu ioctl
4108 :Parameters: struct kvm_s390_irq_state (in)      4108 :Parameters: struct kvm_s390_irq_state (in)
4109 :Returns: 0 on success,                          4109 :Returns: 0 on success,
4110           -EFAULT if the buffer address was i    4110           -EFAULT if the buffer address was invalid,
4111           -EINVAL for an invalid buffer lengt    4111           -EINVAL for an invalid buffer length (see below),
4112           -EBUSY if there were already interr    4112           -EBUSY if there were already interrupts pending,
4113           errors occurring when actually inje    4113           errors occurring when actually injecting the
4114           interrupt. See KVM_S390_IRQ.           4114           interrupt. See KVM_S390_IRQ.
4115                                                  4115 
4116 This ioctl allows userspace to set the comple    4116 This ioctl allows userspace to set the complete state of all cpu-local
4117 interrupts currently pending for the vcpu. It    4117 interrupts currently pending for the vcpu. It is intended for restoring
4118 interrupt state after a migration. The input     4118 interrupt state after a migration. The input parameter is a userspace buffer
4119 containing a struct kvm_s390_irq_state::         4119 containing a struct kvm_s390_irq_state::
4120                                                  4120 
4121   struct kvm_s390_irq_state {                    4121   struct kvm_s390_irq_state {
4122         __u64 buf;                               4122         __u64 buf;
4123         __u32 flags;        /* will stay unus    4123         __u32 flags;        /* will stay unused for compatibility reasons */
4124         __u32 len;                               4124         __u32 len;
4125         __u32 reserved[4];  /* will stay unus    4125         __u32 reserved[4];  /* will stay unused for compatibility reasons */
4126   };                                             4126   };
4127                                                  4127 
4128 The restrictions for flags and reserved apply    4128 The restrictions for flags and reserved apply as well.
4129 (see KVM_S390_GET_IRQ_STATE)                     4129 (see KVM_S390_GET_IRQ_STATE)
4130                                                  4130 
4131 The userspace memory referenced by buf contai    4131 The userspace memory referenced by buf contains a struct kvm_s390_irq
4132 for each interrupt to be injected into the gu    4132 for each interrupt to be injected into the guest.
4133 If one of the interrupts could not be injecte    4133 If one of the interrupts could not be injected for some reason the
4134 ioctl aborts.                                    4134 ioctl aborts.
4135                                                  4135 
4136 len must be a multiple of sizeof(struct kvm_s    4136 len must be a multiple of sizeof(struct kvm_s390_irq). It must be > 0
4137 and it must not exceed (max_vcpus + 32) * siz    4137 and it must not exceed (max_vcpus + 32) * sizeof(struct kvm_s390_irq),
4138 which is the maximum number of possibly pendi    4138 which is the maximum number of possibly pending cpu-local interrupts.
4139                                                  4139 
4140 4.96 KVM_SMI                                     4140 4.96 KVM_SMI
4141 ------------                                     4141 ------------
4142                                                  4142 
4143 :Capability: KVM_CAP_X86_SMM                     4143 :Capability: KVM_CAP_X86_SMM
4144 :Architectures: x86                              4144 :Architectures: x86
4145 :Type: vcpu ioctl                                4145 :Type: vcpu ioctl
4146 :Parameters: none                                4146 :Parameters: none
4147 :Returns: 0 on success, -1 on error              4147 :Returns: 0 on success, -1 on error
4148                                                  4148 
4149 Queues an SMI on the thread's vcpu.              4149 Queues an SMI on the thread's vcpu.
4150                                                  4150 
4151 4.97 KVM_X86_SET_MSR_FILTER                      4151 4.97 KVM_X86_SET_MSR_FILTER
4152 ----------------------------                     4152 ----------------------------
4153                                                  4153 
4154 :Capability: KVM_CAP_X86_MSR_FILTER              4154 :Capability: KVM_CAP_X86_MSR_FILTER
4155 :Architectures: x86                              4155 :Architectures: x86
4156 :Type: vm ioctl                                  4156 :Type: vm ioctl
4157 :Parameters: struct kvm_msr_filter               4157 :Parameters: struct kvm_msr_filter
4158 :Returns: 0 on success, < 0 on error             4158 :Returns: 0 on success, < 0 on error
4159                                                  4159 
4160 ::                                               4160 ::
4161                                                  4161 
4162   struct kvm_msr_filter_range {                  4162   struct kvm_msr_filter_range {
4163   #define KVM_MSR_FILTER_READ  (1 << 0)          4163   #define KVM_MSR_FILTER_READ  (1 << 0)
4164   #define KVM_MSR_FILTER_WRITE (1 << 1)          4164   #define KVM_MSR_FILTER_WRITE (1 << 1)
4165         __u32 flags;                             4165         __u32 flags;
4166         __u32 nmsrs; /* number of msrs in bit    4166         __u32 nmsrs; /* number of msrs in bitmap */
4167         __u32 base;  /* MSR index the bitmap     4167         __u32 base;  /* MSR index the bitmap starts at */
4168         __u8 *bitmap; /* a 1 bit allows the o    4168         __u8 *bitmap; /* a 1 bit allows the operations in flags, 0 denies */
4169   };                                             4169   };
4170                                                  4170 
4171   #define KVM_MSR_FILTER_MAX_RANGES 16           4171   #define KVM_MSR_FILTER_MAX_RANGES 16
4172   struct kvm_msr_filter {                        4172   struct kvm_msr_filter {
4173   #define KVM_MSR_FILTER_DEFAULT_ALLOW (0 <<     4173   #define KVM_MSR_FILTER_DEFAULT_ALLOW (0 << 0)
4174   #define KVM_MSR_FILTER_DEFAULT_DENY  (1 <<     4174   #define KVM_MSR_FILTER_DEFAULT_DENY  (1 << 0)
4175         __u32 flags;                             4175         __u32 flags;
4176         struct kvm_msr_filter_range ranges[KV    4176         struct kvm_msr_filter_range ranges[KVM_MSR_FILTER_MAX_RANGES];
4177   };                                             4177   };
4178                                                  4178 
4179 flags values for ``struct kvm_msr_filter_rang    4179 flags values for ``struct kvm_msr_filter_range``:
4180                                                  4180 
4181 ``KVM_MSR_FILTER_READ``                          4181 ``KVM_MSR_FILTER_READ``
4182                                                  4182 
4183   Filter read accesses to MSRs using the give    4183   Filter read accesses to MSRs using the given bitmap. A 0 in the bitmap
4184   indicates that read accesses should be deni    4184   indicates that read accesses should be denied, while a 1 indicates that
4185   a read for a particular MSR should be allow    4185   a read for a particular MSR should be allowed regardless of the default
4186   filter action.                                 4186   filter action.
4187                                                  4187 
4188 ``KVM_MSR_FILTER_WRITE``                         4188 ``KVM_MSR_FILTER_WRITE``
4189                                                  4189 
4190   Filter write accesses to MSRs using the giv    4190   Filter write accesses to MSRs using the given bitmap. A 0 in the bitmap
4191   indicates that write accesses should be den    4191   indicates that write accesses should be denied, while a 1 indicates that
4192   a write for a particular MSR should be allo    4192   a write for a particular MSR should be allowed regardless of the default
4193   filter action.                                 4193   filter action.
4194                                                  4194 
4195 flags values for ``struct kvm_msr_filter``:      4195 flags values for ``struct kvm_msr_filter``:
4196                                                  4196 
4197 ``KVM_MSR_FILTER_DEFAULT_ALLOW``                 4197 ``KVM_MSR_FILTER_DEFAULT_ALLOW``
4198                                                  4198 
4199   If no filter range matches an MSR index tha    4199   If no filter range matches an MSR index that is getting accessed, KVM will
4200   allow accesses to all MSRs by default.         4200   allow accesses to all MSRs by default.
4201                                                  4201 
4202 ``KVM_MSR_FILTER_DEFAULT_DENY``                  4202 ``KVM_MSR_FILTER_DEFAULT_DENY``
4203                                                  4203 
4204   If no filter range matches an MSR index tha    4204   If no filter range matches an MSR index that is getting accessed, KVM will
4205   deny accesses to all MSRs by default.          4205   deny accesses to all MSRs by default.
4206                                                  4206 
4207 This ioctl allows userspace to define up to 1    4207 This ioctl allows userspace to define up to 16 bitmaps of MSR ranges to deny
4208 guest MSR accesses that would normally be all    4208 guest MSR accesses that would normally be allowed by KVM.  If an MSR is not
4209 covered by a specific range, the "default" fi    4209 covered by a specific range, the "default" filtering behavior applies.  Each
4210 bitmap range covers MSRs from [base .. base+n    4210 bitmap range covers MSRs from [base .. base+nmsrs).
4211                                                  4211 
4212 If an MSR access is denied by userspace, the     4212 If an MSR access is denied by userspace, the resulting KVM behavior depends on
4213 whether or not KVM_CAP_X86_USER_SPACE_MSR's K    4213 whether or not KVM_CAP_X86_USER_SPACE_MSR's KVM_MSR_EXIT_REASON_FILTER is
4214 enabled.  If KVM_MSR_EXIT_REASON_FILTER is en    4214 enabled.  If KVM_MSR_EXIT_REASON_FILTER is enabled, KVM will exit to userspace
4215 on denied accesses, i.e. userspace effectivel    4215 on denied accesses, i.e. userspace effectively intercepts the MSR access.  If
4216 KVM_MSR_EXIT_REASON_FILTER is not enabled, KV    4216 KVM_MSR_EXIT_REASON_FILTER is not enabled, KVM will inject a #GP into the guest
4217 on denied accesses.  Note, if an MSR access i    4217 on denied accesses.  Note, if an MSR access is denied during emulation of MSR
4218 load/stores during VMX transitions, KVM ignor    4218 load/stores during VMX transitions, KVM ignores KVM_MSR_EXIT_REASON_FILTER.
4219 See the below warning for full details.          4219 See the below warning for full details.
4220                                                  4220 
4221 If an MSR access is allowed by userspace, KVM    4221 If an MSR access is allowed by userspace, KVM will emulate and/or virtualize
4222 the access in accordance with the vCPU model.    4222 the access in accordance with the vCPU model.  Note, KVM may still ultimately
4223 inject a #GP if an access is allowed by users    4223 inject a #GP if an access is allowed by userspace, e.g. if KVM doesn't support
4224 the MSR, or to follow architectural behavior     4224 the MSR, or to follow architectural behavior for the MSR.
4225                                                  4225 
4226 By default, KVM operates in KVM_MSR_FILTER_DE    4226 By default, KVM operates in KVM_MSR_FILTER_DEFAULT_ALLOW mode with no MSR range
4227 filters.                                         4227 filters.
4228                                                  4228 
4229 Calling this ioctl with an empty set of range    4229 Calling this ioctl with an empty set of ranges (all nmsrs == 0) disables MSR
4230 filtering. In that mode, ``KVM_MSR_FILTER_DEF    4230 filtering. In that mode, ``KVM_MSR_FILTER_DEFAULT_DENY`` is invalid and causes
4231 an error.                                        4231 an error.
4232                                                  4232 
4233 .. warning::                                     4233 .. warning::
4234    MSR accesses that are side effects of inst    4234    MSR accesses that are side effects of instruction execution (emulated or
4235    native) are not filtered as hardware does     4235    native) are not filtered as hardware does not honor MSR bitmaps outside of
4236    RDMSR and WRMSR, and KVM mimics that behav    4236    RDMSR and WRMSR, and KVM mimics that behavior when emulating instructions
4237    to avoid pointless divergence from hardwar    4237    to avoid pointless divergence from hardware.  E.g. RDPID reads MSR_TSC_AUX,
4238    SYSENTER reads the SYSENTER MSRs, etc.        4238    SYSENTER reads the SYSENTER MSRs, etc.
4239                                                  4239 
4240    MSRs that are loaded/stored via dedicated     4240    MSRs that are loaded/stored via dedicated VMCS fields are not filtered as
4241    part of VM-Enter/VM-Exit emulation.           4241    part of VM-Enter/VM-Exit emulation.
4242                                                  4242 
4243    MSRs that are loaded/store via VMX's load/    4243    MSRs that are loaded/store via VMX's load/store lists _are_ filtered as part
4244    of VM-Enter/VM-Exit emulation.  If an MSR     4244    of VM-Enter/VM-Exit emulation.  If an MSR access is denied on VM-Enter, KVM
4245    synthesizes a consistency check VM-Exit(EX    4245    synthesizes a consistency check VM-Exit(EXIT_REASON_MSR_LOAD_FAIL).  If an
4246    MSR access is denied on VM-Exit, KVM synth    4246    MSR access is denied on VM-Exit, KVM synthesizes a VM-Abort.  In short, KVM
4247    extends Intel's architectural list of MSRs    4247    extends Intel's architectural list of MSRs that cannot be loaded/saved via
4248    the VM-Enter/VM-Exit MSR list.  It is plat    4248    the VM-Enter/VM-Exit MSR list.  It is platform owner's responsibility to
4249    to communicate any such restrictions to th    4249    to communicate any such restrictions to their end users.
4250                                                  4250 
4251    x2APIC MSR accesses cannot be filtered (KV    4251    x2APIC MSR accesses cannot be filtered (KVM silently ignores filters that
4252    cover any x2APIC MSRs).                       4252    cover any x2APIC MSRs).
4253                                                  4253 
4254 Note, invoking this ioctl while a vCPU is run    4254 Note, invoking this ioctl while a vCPU is running is inherently racy.  However,
4255 KVM does guarantee that vCPUs will see either    4255 KVM does guarantee that vCPUs will see either the previous filter or the new
4256 filter, e.g. MSRs with identical settings in     4256 filter, e.g. MSRs with identical settings in both the old and new filter will
4257 have deterministic behavior.                     4257 have deterministic behavior.
4258                                                  4258 
4259 Similarly, if userspace wishes to intercept o    4259 Similarly, if userspace wishes to intercept on denied accesses,
4260 KVM_MSR_EXIT_REASON_FILTER must be enabled be    4260 KVM_MSR_EXIT_REASON_FILTER must be enabled before activating any filters, and
4261 left enabled until after all filters are deac    4261 left enabled until after all filters are deactivated.  Failure to do so may
4262 result in KVM injecting a #GP instead of exit    4262 result in KVM injecting a #GP instead of exiting to userspace.
4263                                                  4263 
4264 4.98 KVM_CREATE_SPAPR_TCE_64                     4264 4.98 KVM_CREATE_SPAPR_TCE_64
4265 ----------------------------                     4265 ----------------------------
4266                                                  4266 
4267 :Capability: KVM_CAP_SPAPR_TCE_64                4267 :Capability: KVM_CAP_SPAPR_TCE_64
4268 :Architectures: powerpc                          4268 :Architectures: powerpc
4269 :Type: vm ioctl                                  4269 :Type: vm ioctl
4270 :Parameters: struct kvm_create_spapr_tce_64 (    4270 :Parameters: struct kvm_create_spapr_tce_64 (in)
4271 :Returns: file descriptor for manipulating th    4271 :Returns: file descriptor for manipulating the created TCE table
4272                                                  4272 
4273 This is an extension for KVM_CAP_SPAPR_TCE wh    4273 This is an extension for KVM_CAP_SPAPR_TCE which only supports 32bit
4274 windows, described in 4.62 KVM_CREATE_SPAPR_T    4274 windows, described in 4.62 KVM_CREATE_SPAPR_TCE
4275                                                  4275 
4276 This capability uses extended struct in ioctl    4276 This capability uses extended struct in ioctl interface::
4277                                                  4277 
4278   /* for KVM_CAP_SPAPR_TCE_64 */                 4278   /* for KVM_CAP_SPAPR_TCE_64 */
4279   struct kvm_create_spapr_tce_64 {               4279   struct kvm_create_spapr_tce_64 {
4280         __u64 liobn;                             4280         __u64 liobn;
4281         __u32 page_shift;                        4281         __u32 page_shift;
4282         __u32 flags;                             4282         __u32 flags;
4283         __u64 offset;   /* in pages */           4283         __u64 offset;   /* in pages */
4284         __u64 size;     /* in pages */           4284         __u64 size;     /* in pages */
4285   };                                             4285   };
4286                                                  4286 
4287 The aim of extension is to support an additio    4287 The aim of extension is to support an additional bigger DMA window with
4288 a variable page size.                            4288 a variable page size.
4289 KVM_CREATE_SPAPR_TCE_64 receives a 64bit wind    4289 KVM_CREATE_SPAPR_TCE_64 receives a 64bit window size, an IOMMU page shift and
4290 a bus offset of the corresponding DMA window,    4290 a bus offset of the corresponding DMA window, @size and @offset are numbers
4291 of IOMMU pages.                                  4291 of IOMMU pages.
4292                                                  4292 
4293 @flags are not used at the moment.               4293 @flags are not used at the moment.
4294                                                  4294 
4295 The rest of functionality is identical to KVM    4295 The rest of functionality is identical to KVM_CREATE_SPAPR_TCE.
4296                                                  4296 
4297 4.99 KVM_REINJECT_CONTROL                        4297 4.99 KVM_REINJECT_CONTROL
4298 -------------------------                        4298 -------------------------
4299                                                  4299 
4300 :Capability: KVM_CAP_REINJECT_CONTROL            4300 :Capability: KVM_CAP_REINJECT_CONTROL
4301 :Architectures: x86                              4301 :Architectures: x86
4302 :Type: vm ioctl                                  4302 :Type: vm ioctl
4303 :Parameters: struct kvm_reinject_control (in)    4303 :Parameters: struct kvm_reinject_control (in)
4304 :Returns: 0 on success,                          4304 :Returns: 0 on success,
4305          -EFAULT if struct kvm_reinject_contr    4305          -EFAULT if struct kvm_reinject_control cannot be read,
4306          -ENXIO if KVM_CREATE_PIT or KVM_CREA    4306          -ENXIO if KVM_CREATE_PIT or KVM_CREATE_PIT2 didn't succeed earlier.
4307                                                  4307 
4308 i8254 (PIT) has two modes, reinject and !rein    4308 i8254 (PIT) has two modes, reinject and !reinject.  The default is reinject,
4309 where KVM queues elapsed i8254 ticks and moni    4309 where KVM queues elapsed i8254 ticks and monitors completion of interrupt from
4310 vector(s) that i8254 injects.  Reinject mode     4310 vector(s) that i8254 injects.  Reinject mode dequeues a tick and injects its
4311 interrupt whenever there isn't a pending inte    4311 interrupt whenever there isn't a pending interrupt from i8254.
4312 !reinject mode injects an interrupt as soon a    4312 !reinject mode injects an interrupt as soon as a tick arrives.
4313                                                  4313 
4314 ::                                               4314 ::
4315                                                  4315 
4316   struct kvm_reinject_control {                  4316   struct kvm_reinject_control {
4317         __u8 pit_reinject;                       4317         __u8 pit_reinject;
4318         __u8 reserved[31];                       4318         __u8 reserved[31];
4319   };                                             4319   };
4320                                                  4320 
4321 pit_reinject = 0 (!reinject mode) is recommen    4321 pit_reinject = 0 (!reinject mode) is recommended, unless running an old
4322 operating system that uses the PIT for timing    4322 operating system that uses the PIT for timing (e.g. Linux 2.4.x).
4323                                                  4323 
4324 4.100 KVM_PPC_CONFIGURE_V3_MMU                   4324 4.100 KVM_PPC_CONFIGURE_V3_MMU
4325 ------------------------------                   4325 ------------------------------
4326                                                  4326 
4327 :Capability: KVM_CAP_PPC_MMU_RADIX or KVM_CAP    4327 :Capability: KVM_CAP_PPC_MMU_RADIX or KVM_CAP_PPC_MMU_HASH_V3
4328 :Architectures: ppc                              4328 :Architectures: ppc
4329 :Type: vm ioctl                                  4329 :Type: vm ioctl
4330 :Parameters: struct kvm_ppc_mmuv3_cfg (in)       4330 :Parameters: struct kvm_ppc_mmuv3_cfg (in)
4331 :Returns: 0 on success,                          4331 :Returns: 0 on success,
4332          -EFAULT if struct kvm_ppc_mmuv3_cfg     4332          -EFAULT if struct kvm_ppc_mmuv3_cfg cannot be read,
4333          -EINVAL if the configuration is inva    4333          -EINVAL if the configuration is invalid
4334                                                  4334 
4335 This ioctl controls whether the guest will us    4335 This ioctl controls whether the guest will use radix or HPT (hashed
4336 page table) translation, and sets the pointer    4336 page table) translation, and sets the pointer to the process table for
4337 the guest.                                       4337 the guest.
4338                                                  4338 
4339 ::                                               4339 ::
4340                                                  4340 
4341   struct kvm_ppc_mmuv3_cfg {                     4341   struct kvm_ppc_mmuv3_cfg {
4342         __u64   flags;                           4342         __u64   flags;
4343         __u64   process_table;                   4343         __u64   process_table;
4344   };                                             4344   };
4345                                                  4345 
4346 There are two bits that can be set in flags;     4346 There are two bits that can be set in flags; KVM_PPC_MMUV3_RADIX and
4347 KVM_PPC_MMUV3_GTSE.  KVM_PPC_MMUV3_RADIX, if     4347 KVM_PPC_MMUV3_GTSE.  KVM_PPC_MMUV3_RADIX, if set, configures the guest
4348 to use radix tree translation, and if clear,     4348 to use radix tree translation, and if clear, to use HPT translation.
4349 KVM_PPC_MMUV3_GTSE, if set and if KVM permits    4349 KVM_PPC_MMUV3_GTSE, if set and if KVM permits it, configures the guest
4350 to be able to use the global TLB and SLB inva    4350 to be able to use the global TLB and SLB invalidation instructions;
4351 if clear, the guest may not use these instruc    4351 if clear, the guest may not use these instructions.
4352                                                  4352 
4353 The process_table field specifies the address    4353 The process_table field specifies the address and size of the guest
4354 process table, which is in the guest's space.    4354 process table, which is in the guest's space.  This field is formatted
4355 as the second doubleword of the partition tab    4355 as the second doubleword of the partition table entry, as defined in
4356 the Power ISA V3.00, Book III section 5.7.6.1    4356 the Power ISA V3.00, Book III section 5.7.6.1.
4357                                                  4357 
4358 4.101 KVM_PPC_GET_RMMU_INFO                      4358 4.101 KVM_PPC_GET_RMMU_INFO
4359 ---------------------------                      4359 ---------------------------
4360                                                  4360 
4361 :Capability: KVM_CAP_PPC_MMU_RADIX               4361 :Capability: KVM_CAP_PPC_MMU_RADIX
4362 :Architectures: ppc                              4362 :Architectures: ppc
4363 :Type: vm ioctl                                  4363 :Type: vm ioctl
4364 :Parameters: struct kvm_ppc_rmmu_info (out)      4364 :Parameters: struct kvm_ppc_rmmu_info (out)
4365 :Returns: 0 on success,                          4365 :Returns: 0 on success,
4366          -EFAULT if struct kvm_ppc_rmmu_info     4366          -EFAULT if struct kvm_ppc_rmmu_info cannot be written,
4367          -EINVAL if no useful information can    4367          -EINVAL if no useful information can be returned
4368                                                  4368 
4369 This ioctl returns a structure containing two    4369 This ioctl returns a structure containing two things: (a) a list
4370 containing supported radix tree geometries, a    4370 containing supported radix tree geometries, and (b) a list that maps
4371 page sizes to put in the "AP" (actual page si    4371 page sizes to put in the "AP" (actual page size) field for the tlbie
4372 (TLB invalidate entry) instruction.              4372 (TLB invalidate entry) instruction.
4373                                                  4373 
4374 ::                                               4374 ::
4375                                                  4375 
4376   struct kvm_ppc_rmmu_info {                     4376   struct kvm_ppc_rmmu_info {
4377         struct kvm_ppc_radix_geom {              4377         struct kvm_ppc_radix_geom {
4378                 __u8    page_shift;              4378                 __u8    page_shift;
4379                 __u8    level_bits[4];           4379                 __u8    level_bits[4];
4380                 __u8    pad[3];                  4380                 __u8    pad[3];
4381         }       geometries[8];                   4381         }       geometries[8];
4382         __u32   ap_encodings[8];                 4382         __u32   ap_encodings[8];
4383   };                                             4383   };
4384                                                  4384 
4385 The geometries[] field gives up to 8 supporte    4385 The geometries[] field gives up to 8 supported geometries for the
4386 radix page table, in terms of the log base 2     4386 radix page table, in terms of the log base 2 of the smallest page
4387 size, and the number of bits indexed at each     4387 size, and the number of bits indexed at each level of the tree, from
4388 the PTE level up to the PGD level in that ord    4388 the PTE level up to the PGD level in that order.  Any unused entries
4389 will have 0 in the page_shift field.             4389 will have 0 in the page_shift field.
4390                                                  4390 
4391 The ap_encodings gives the supported page siz    4391 The ap_encodings gives the supported page sizes and their AP field
4392 encodings, encoded with the AP value in the t    4392 encodings, encoded with the AP value in the top 3 bits and the log
4393 base 2 of the page size in the bottom 6 bits.    4393 base 2 of the page size in the bottom 6 bits.
4394                                                  4394 
4395 4.102 KVM_PPC_RESIZE_HPT_PREPARE                 4395 4.102 KVM_PPC_RESIZE_HPT_PREPARE
4396 --------------------------------                 4396 --------------------------------
4397                                                  4397 
4398 :Capability: KVM_CAP_SPAPR_RESIZE_HPT            4398 :Capability: KVM_CAP_SPAPR_RESIZE_HPT
4399 :Architectures: powerpc                          4399 :Architectures: powerpc
4400 :Type: vm ioctl                                  4400 :Type: vm ioctl
4401 :Parameters: struct kvm_ppc_resize_hpt (in)      4401 :Parameters: struct kvm_ppc_resize_hpt (in)
4402 :Returns: 0 on successful completion,            4402 :Returns: 0 on successful completion,
4403          >0 if a new HPT is being prepared, t    4403          >0 if a new HPT is being prepared, the value is an estimated
4404          number of milliseconds until prepara    4404          number of milliseconds until preparation is complete,
4405          -EFAULT if struct kvm_reinject_contr    4405          -EFAULT if struct kvm_reinject_control cannot be read,
4406          -EINVAL if the supplied shift or fla    4406          -EINVAL if the supplied shift or flags are invalid,
4407          -ENOMEM if unable to allocate the ne    4407          -ENOMEM if unable to allocate the new HPT,
4408                                                  4408 
4409 Used to implement the PAPR extension for runt    4409 Used to implement the PAPR extension for runtime resizing of a guest's
4410 Hashed Page Table (HPT).  Specifically this s    4410 Hashed Page Table (HPT).  Specifically this starts, stops or monitors
4411 the preparation of a new potential HPT for th    4411 the preparation of a new potential HPT for the guest, essentially
4412 implementing the H_RESIZE_HPT_PREPARE hyperca    4412 implementing the H_RESIZE_HPT_PREPARE hypercall.
4413                                                  4413 
4414 ::                                               4414 ::
4415                                                  4415 
4416   struct kvm_ppc_resize_hpt {                    4416   struct kvm_ppc_resize_hpt {
4417         __u64 flags;                             4417         __u64 flags;
4418         __u32 shift;                             4418         __u32 shift;
4419         __u32 pad;                               4419         __u32 pad;
4420   };                                             4420   };
4421                                                  4421 
4422 If called with shift > 0 when there is no pen    4422 If called with shift > 0 when there is no pending HPT for the guest,
4423 this begins preparation of a new pending HPT     4423 this begins preparation of a new pending HPT of size 2^(shift) bytes.
4424 It then returns a positive integer with the e    4424 It then returns a positive integer with the estimated number of
4425 milliseconds until preparation is complete.      4425 milliseconds until preparation is complete.
4426                                                  4426 
4427 If called when there is a pending HPT whose s    4427 If called when there is a pending HPT whose size does not match that
4428 requested in the parameters, discards the exi    4428 requested in the parameters, discards the existing pending HPT and
4429 creates a new one as above.                      4429 creates a new one as above.
4430                                                  4430 
4431 If called when there is a pending HPT of the     4431 If called when there is a pending HPT of the size requested, will:
4432                                                  4432 
4433   * If preparation of the pending HPT is alre    4433   * If preparation of the pending HPT is already complete, return 0
4434   * If preparation of the pending HPT has fai    4434   * If preparation of the pending HPT has failed, return an error
4435     code, then discard the pending HPT.          4435     code, then discard the pending HPT.
4436   * If preparation of the pending HPT is stil    4436   * If preparation of the pending HPT is still in progress, return an
4437     estimated number of milliseconds until pr    4437     estimated number of milliseconds until preparation is complete.
4438                                                  4438 
4439 If called with shift == 0, discards any curre    4439 If called with shift == 0, discards any currently pending HPT and
4440 returns 0 (i.e. cancels any in-progress prepa    4440 returns 0 (i.e. cancels any in-progress preparation).
4441                                                  4441 
4442 flags is reserved for future expansion, curre    4442 flags is reserved for future expansion, currently setting any bits in
4443 flags will result in an -EINVAL.                 4443 flags will result in an -EINVAL.
4444                                                  4444 
4445 Normally this will be called repeatedly with     4445 Normally this will be called repeatedly with the same parameters until
4446 it returns <= 0.  The first call will initiat    4446 it returns <= 0.  The first call will initiate preparation, subsequent
4447 ones will monitor preparation until it comple    4447 ones will monitor preparation until it completes or fails.
4448                                                  4448 
4449 4.103 KVM_PPC_RESIZE_HPT_COMMIT                  4449 4.103 KVM_PPC_RESIZE_HPT_COMMIT
4450 -------------------------------                  4450 -------------------------------
4451                                                  4451 
4452 :Capability: KVM_CAP_SPAPR_RESIZE_HPT            4452 :Capability: KVM_CAP_SPAPR_RESIZE_HPT
4453 :Architectures: powerpc                          4453 :Architectures: powerpc
4454 :Type: vm ioctl                                  4454 :Type: vm ioctl
4455 :Parameters: struct kvm_ppc_resize_hpt (in)      4455 :Parameters: struct kvm_ppc_resize_hpt (in)
4456 :Returns: 0 on successful completion,            4456 :Returns: 0 on successful completion,
4457          -EFAULT if struct kvm_reinject_contr    4457          -EFAULT if struct kvm_reinject_control cannot be read,
4458          -EINVAL if the supplied shift or fla    4458          -EINVAL if the supplied shift or flags are invalid,
4459          -ENXIO is there is no pending HPT, o    4459          -ENXIO is there is no pending HPT, or the pending HPT doesn't
4460          have the requested size,                4460          have the requested size,
4461          -EBUSY if the pending HPT is not ful    4461          -EBUSY if the pending HPT is not fully prepared,
4462          -ENOSPC if there was a hash collisio    4462          -ENOSPC if there was a hash collision when moving existing
4463          HPT entries to the new HPT,             4463          HPT entries to the new HPT,
4464          -EIO on other error conditions          4464          -EIO on other error conditions
4465                                                  4465 
4466 Used to implement the PAPR extension for runt    4466 Used to implement the PAPR extension for runtime resizing of a guest's
4467 Hashed Page Table (HPT).  Specifically this r    4467 Hashed Page Table (HPT).  Specifically this requests that the guest be
4468 transferred to working with the new HPT, esse    4468 transferred to working with the new HPT, essentially implementing the
4469 H_RESIZE_HPT_COMMIT hypercall.                   4469 H_RESIZE_HPT_COMMIT hypercall.
4470                                                  4470 
4471 ::                                               4471 ::
4472                                                  4472 
4473   struct kvm_ppc_resize_hpt {                    4473   struct kvm_ppc_resize_hpt {
4474         __u64 flags;                             4474         __u64 flags;
4475         __u32 shift;                             4475         __u32 shift;
4476         __u32 pad;                               4476         __u32 pad;
4477   };                                             4477   };
4478                                                  4478 
4479 This should only be called after KVM_PPC_RESI    4479 This should only be called after KVM_PPC_RESIZE_HPT_PREPARE has
4480 returned 0 with the same parameters.  In othe    4480 returned 0 with the same parameters.  In other cases
4481 KVM_PPC_RESIZE_HPT_COMMIT will return an erro    4481 KVM_PPC_RESIZE_HPT_COMMIT will return an error (usually -ENXIO or
4482 -EBUSY, though others may be possible if the     4482 -EBUSY, though others may be possible if the preparation was started,
4483 but failed).                                     4483 but failed).
4484                                                  4484 
4485 This will have undefined effects on the guest    4485 This will have undefined effects on the guest if it has not already
4486 placed itself in a quiescent state where no v    4486 placed itself in a quiescent state where no vcpu will make MMU enabled
4487 memory accesses.                                 4487 memory accesses.
4488                                                  4488 
4489 On successful completion, the pending HPT wil    4489 On successful completion, the pending HPT will become the guest's active
4490 HPT and the previous HPT will be discarded.      4490 HPT and the previous HPT will be discarded.
4491                                                  4491 
4492 On failure, the guest will still be operating    4492 On failure, the guest will still be operating on its previous HPT.
4493                                                  4493 
4494 4.104 KVM_X86_GET_MCE_CAP_SUPPORTED              4494 4.104 KVM_X86_GET_MCE_CAP_SUPPORTED
4495 -----------------------------------              4495 -----------------------------------
4496                                                  4496 
4497 :Capability: KVM_CAP_MCE                         4497 :Capability: KVM_CAP_MCE
4498 :Architectures: x86                              4498 :Architectures: x86
4499 :Type: system ioctl                              4499 :Type: system ioctl
4500 :Parameters: u64 mce_cap (out)                   4500 :Parameters: u64 mce_cap (out)
4501 :Returns: 0 on success, -1 on error              4501 :Returns: 0 on success, -1 on error
4502                                                  4502 
4503 Returns supported MCE capabilities. The u64 m    4503 Returns supported MCE capabilities. The u64 mce_cap parameter
4504 has the same format as the MSR_IA32_MCG_CAP r    4504 has the same format as the MSR_IA32_MCG_CAP register. Supported
4505 capabilities will have the corresponding bits    4505 capabilities will have the corresponding bits set.
4506                                                  4506 
4507 4.105 KVM_X86_SETUP_MCE                          4507 4.105 KVM_X86_SETUP_MCE
4508 -----------------------                          4508 -----------------------
4509                                                  4509 
4510 :Capability: KVM_CAP_MCE                         4510 :Capability: KVM_CAP_MCE
4511 :Architectures: x86                              4511 :Architectures: x86
4512 :Type: vcpu ioctl                                4512 :Type: vcpu ioctl
4513 :Parameters: u64 mcg_cap (in)                    4513 :Parameters: u64 mcg_cap (in)
4514 :Returns: 0 on success,                          4514 :Returns: 0 on success,
4515          -EFAULT if u64 mcg_cap cannot be rea    4515          -EFAULT if u64 mcg_cap cannot be read,
4516          -EINVAL if the requested number of b    4516          -EINVAL if the requested number of banks is invalid,
4517          -EINVAL if requested MCE capability     4517          -EINVAL if requested MCE capability is not supported.
4518                                                  4518 
4519 Initializes MCE support for use. The u64 mcg_    4519 Initializes MCE support for use. The u64 mcg_cap parameter
4520 has the same format as the MSR_IA32_MCG_CAP r    4520 has the same format as the MSR_IA32_MCG_CAP register and
4521 specifies which capabilities should be enable    4521 specifies which capabilities should be enabled. The maximum
4522 supported number of error-reporting banks can    4522 supported number of error-reporting banks can be retrieved when
4523 checking for KVM_CAP_MCE. The supported capab    4523 checking for KVM_CAP_MCE. The supported capabilities can be
4524 retrieved with KVM_X86_GET_MCE_CAP_SUPPORTED.    4524 retrieved with KVM_X86_GET_MCE_CAP_SUPPORTED.
4525                                                  4525 
4526 4.106 KVM_X86_SET_MCE                            4526 4.106 KVM_X86_SET_MCE
4527 ---------------------                            4527 ---------------------
4528                                                  4528 
4529 :Capability: KVM_CAP_MCE                         4529 :Capability: KVM_CAP_MCE
4530 :Architectures: x86                              4530 :Architectures: x86
4531 :Type: vcpu ioctl                                4531 :Type: vcpu ioctl
4532 :Parameters: struct kvm_x86_mce (in)             4532 :Parameters: struct kvm_x86_mce (in)
4533 :Returns: 0 on success,                          4533 :Returns: 0 on success,
4534          -EFAULT if struct kvm_x86_mce cannot    4534          -EFAULT if struct kvm_x86_mce cannot be read,
4535          -EINVAL if the bank number is invali    4535          -EINVAL if the bank number is invalid,
4536          -EINVAL if VAL bit is not set in sta    4536          -EINVAL if VAL bit is not set in status field.
4537                                                  4537 
4538 Inject a machine check error (MCE) into the g    4538 Inject a machine check error (MCE) into the guest. The input
4539 parameter is::                                   4539 parameter is::
4540                                                  4540 
4541   struct kvm_x86_mce {                           4541   struct kvm_x86_mce {
4542         __u64 status;                            4542         __u64 status;
4543         __u64 addr;                              4543         __u64 addr;
4544         __u64 misc;                              4544         __u64 misc;
4545         __u64 mcg_status;                        4545         __u64 mcg_status;
4546         __u8 bank;                               4546         __u8 bank;
4547         __u8 pad1[7];                            4547         __u8 pad1[7];
4548         __u64 pad2[3];                           4548         __u64 pad2[3];
4549   };                                             4549   };
4550                                                  4550 
4551 If the MCE being reported is an uncorrected e    4551 If the MCE being reported is an uncorrected error, KVM will
4552 inject it as an MCE exception into the guest.    4552 inject it as an MCE exception into the guest. If the guest
4553 MCG_STATUS register reports that an MCE is in    4553 MCG_STATUS register reports that an MCE is in progress, KVM
4554 causes an KVM_EXIT_SHUTDOWN vmexit.              4554 causes an KVM_EXIT_SHUTDOWN vmexit.
4555                                                  4555 
4556 Otherwise, if the MCE is a corrected error, K    4556 Otherwise, if the MCE is a corrected error, KVM will just
4557 store it in the corresponding bank (provided     4557 store it in the corresponding bank (provided this bank is
4558 not holding a previously reported uncorrected    4558 not holding a previously reported uncorrected error).
4559                                                  4559 
4560 4.107 KVM_S390_GET_CMMA_BITS                     4560 4.107 KVM_S390_GET_CMMA_BITS
4561 ----------------------------                     4561 ----------------------------
4562                                                  4562 
4563 :Capability: KVM_CAP_S390_CMMA_MIGRATION         4563 :Capability: KVM_CAP_S390_CMMA_MIGRATION
4564 :Architectures: s390                             4564 :Architectures: s390
4565 :Type: vm ioctl                                  4565 :Type: vm ioctl
4566 :Parameters: struct kvm_s390_cmma_log (in, ou    4566 :Parameters: struct kvm_s390_cmma_log (in, out)
4567 :Returns: 0 on success, a negative value on e    4567 :Returns: 0 on success, a negative value on error
4568                                                  4568 
4569 Errors:                                          4569 Errors:
4570                                                  4570 
4571   ======     ================================    4571   ======     =============================================================
4572   ENOMEM     not enough memory can be allocat    4572   ENOMEM     not enough memory can be allocated to complete the task
4573   ENXIO      if CMMA is not enabled              4573   ENXIO      if CMMA is not enabled
4574   EINVAL     if KVM_S390_CMMA_PEEK is not set    4574   EINVAL     if KVM_S390_CMMA_PEEK is not set but migration mode was not enabled
4575   EINVAL     if KVM_S390_CMMA_PEEK is not set    4575   EINVAL     if KVM_S390_CMMA_PEEK is not set but dirty tracking has been
4576              disabled (and thus migration mod    4576              disabled (and thus migration mode was automatically disabled)
4577   EFAULT     if the userspace address is inva    4577   EFAULT     if the userspace address is invalid or if no page table is
4578              present for the addresses (e.g.     4578              present for the addresses (e.g. when using hugepages).
4579   ======     ================================    4579   ======     =============================================================
4580                                                  4580 
4581 This ioctl is used to get the values of the C    4581 This ioctl is used to get the values of the CMMA bits on the s390
4582 architecture. It is meant to be used in two s    4582 architecture. It is meant to be used in two scenarios:
4583                                                  4583 
4584 - During live migration to save the CMMA valu    4584 - During live migration to save the CMMA values. Live migration needs
4585   to be enabled via the KVM_REQ_START_MIGRATI    4585   to be enabled via the KVM_REQ_START_MIGRATION VM property.
4586 - To non-destructively peek at the CMMA value    4586 - To non-destructively peek at the CMMA values, with the flag
4587   KVM_S390_CMMA_PEEK set.                        4587   KVM_S390_CMMA_PEEK set.
4588                                                  4588 
4589 The ioctl takes parameters via the kvm_s390_c    4589 The ioctl takes parameters via the kvm_s390_cmma_log struct. The desired
4590 values are written to a buffer whose location    4590 values are written to a buffer whose location is indicated via the "values"
4591 member in the kvm_s390_cmma_log struct.  The     4591 member in the kvm_s390_cmma_log struct.  The values in the input struct are
4592 also updated as needed.                          4592 also updated as needed.
4593                                                  4593 
4594 Each CMMA value takes up one byte.               4594 Each CMMA value takes up one byte.
4595                                                  4595 
4596 ::                                               4596 ::
4597                                                  4597 
4598   struct kvm_s390_cmma_log {                     4598   struct kvm_s390_cmma_log {
4599         __u64 start_gfn;                         4599         __u64 start_gfn;
4600         __u32 count;                             4600         __u32 count;
4601         __u32 flags;                             4601         __u32 flags;
4602         union {                                  4602         union {
4603                 __u64 remaining;                 4603                 __u64 remaining;
4604                 __u64 mask;                      4604                 __u64 mask;
4605         };                                       4605         };
4606         __u64 values;                            4606         __u64 values;
4607   };                                             4607   };
4608                                                  4608 
4609 start_gfn is the number of the first guest fr    4609 start_gfn is the number of the first guest frame whose CMMA values are
4610 to be retrieved,                                 4610 to be retrieved,
4611                                                  4611 
4612 count is the length of the buffer in bytes,      4612 count is the length of the buffer in bytes,
4613                                                  4613 
4614 values points to the buffer where the result     4614 values points to the buffer where the result will be written to.
4615                                                  4615 
4616 If count is greater than KVM_S390_SKEYS_MAX,     4616 If count is greater than KVM_S390_SKEYS_MAX, then it is considered to be
4617 KVM_S390_SKEYS_MAX. KVM_S390_SKEYS_MAX is re-    4617 KVM_S390_SKEYS_MAX. KVM_S390_SKEYS_MAX is re-used for consistency with
4618 other ioctls.                                    4618 other ioctls.
4619                                                  4619 
4620 The result is written in the buffer pointed t    4620 The result is written in the buffer pointed to by the field values, and
4621 the values of the input parameter are updated    4621 the values of the input parameter are updated as follows.
4622                                                  4622 
4623 Depending on the flags, different actions are    4623 Depending on the flags, different actions are performed. The only
4624 supported flag so far is KVM_S390_CMMA_PEEK.     4624 supported flag so far is KVM_S390_CMMA_PEEK.
4625                                                  4625 
4626 The default behaviour if KVM_S390_CMMA_PEEK i    4626 The default behaviour if KVM_S390_CMMA_PEEK is not set is:
4627 start_gfn will indicate the first page frame     4627 start_gfn will indicate the first page frame whose CMMA bits were dirty.
4628 It is not necessarily the same as the one pas    4628 It is not necessarily the same as the one passed as input, as clean pages
4629 are skipped.                                     4629 are skipped.
4630                                                  4630 
4631 count will indicate the number of bytes actua    4631 count will indicate the number of bytes actually written in the buffer.
4632 It can (and very often will) be smaller than     4632 It can (and very often will) be smaller than the input value, since the
4633 buffer is only filled until 16 bytes of clean    4633 buffer is only filled until 16 bytes of clean values are found (which
4634 are then not copied in the buffer). Since a C    4634 are then not copied in the buffer). Since a CMMA migration block needs
4635 the base address and the length, for a total     4635 the base address and the length, for a total of 16 bytes, we will send
4636 back some clean data if there is some dirty d    4636 back some clean data if there is some dirty data afterwards, as long as
4637 the size of the clean data does not exceed th    4637 the size of the clean data does not exceed the size of the header. This
4638 allows to minimize the amount of data to be s    4638 allows to minimize the amount of data to be saved or transferred over
4639 the network at the expense of more roundtrips    4639 the network at the expense of more roundtrips to userspace. The next
4640 invocation of the ioctl will skip over all th    4640 invocation of the ioctl will skip over all the clean values, saving
4641 potentially more than just the 16 bytes we fo    4641 potentially more than just the 16 bytes we found.
4642                                                  4642 
4643 If KVM_S390_CMMA_PEEK is set:                    4643 If KVM_S390_CMMA_PEEK is set:
4644 the existing storage attributes are read even    4644 the existing storage attributes are read even when not in migration
4645 mode, and no other action is performed;          4645 mode, and no other action is performed;
4646                                                  4646 
4647 the output start_gfn will be equal to the inp    4647 the output start_gfn will be equal to the input start_gfn,
4648                                                  4648 
4649 the output count will be equal to the input c    4649 the output count will be equal to the input count, except if the end of
4650 memory has been reached.                         4650 memory has been reached.
4651                                                  4651 
4652 In both cases:                                   4652 In both cases:
4653 the field "remaining" will indicate the total    4653 the field "remaining" will indicate the total number of dirty CMMA values
4654 still remaining, or 0 if KVM_S390_CMMA_PEEK i    4654 still remaining, or 0 if KVM_S390_CMMA_PEEK is set and migration mode is
4655 not enabled.                                     4655 not enabled.
4656                                                  4656 
4657 mask is unused.                                  4657 mask is unused.
4658                                                  4658 
4659 values points to the userspace buffer where t    4659 values points to the userspace buffer where the result will be stored.
4660                                                  4660 
4661 4.108 KVM_S390_SET_CMMA_BITS                     4661 4.108 KVM_S390_SET_CMMA_BITS
4662 ----------------------------                     4662 ----------------------------
4663                                                  4663 
4664 :Capability: KVM_CAP_S390_CMMA_MIGRATION         4664 :Capability: KVM_CAP_S390_CMMA_MIGRATION
4665 :Architectures: s390                             4665 :Architectures: s390
4666 :Type: vm ioctl                                  4666 :Type: vm ioctl
4667 :Parameters: struct kvm_s390_cmma_log (in)       4667 :Parameters: struct kvm_s390_cmma_log (in)
4668 :Returns: 0 on success, a negative value on e    4668 :Returns: 0 on success, a negative value on error
4669                                                  4669 
4670 This ioctl is used to set the values of the C    4670 This ioctl is used to set the values of the CMMA bits on the s390
4671 architecture. It is meant to be used during l    4671 architecture. It is meant to be used during live migration to restore
4672 the CMMA values, but there are no restriction    4672 the CMMA values, but there are no restrictions on its use.
4673 The ioctl takes parameters via the kvm_s390_c    4673 The ioctl takes parameters via the kvm_s390_cmma_values struct.
4674 Each CMMA value takes up one byte.               4674 Each CMMA value takes up one byte.
4675                                                  4675 
4676 ::                                               4676 ::
4677                                                  4677 
4678   struct kvm_s390_cmma_log {                     4678   struct kvm_s390_cmma_log {
4679         __u64 start_gfn;                         4679         __u64 start_gfn;
4680         __u32 count;                             4680         __u32 count;
4681         __u32 flags;                             4681         __u32 flags;
4682         union {                                  4682         union {
4683                 __u64 remaining;                 4683                 __u64 remaining;
4684                 __u64 mask;                      4684                 __u64 mask;
4685         };                                       4685         };
4686         __u64 values;                            4686         __u64 values;
4687   };                                             4687   };
4688                                                  4688 
4689 start_gfn indicates the starting guest frame     4689 start_gfn indicates the starting guest frame number,
4690                                                  4690 
4691 count indicates how many values are to be con    4691 count indicates how many values are to be considered in the buffer,
4692                                                  4692 
4693 flags is not used and must be 0.                 4693 flags is not used and must be 0.
4694                                                  4694 
4695 mask indicates which PGSTE bits are to be con    4695 mask indicates which PGSTE bits are to be considered.
4696                                                  4696 
4697 remaining is not used.                           4697 remaining is not used.
4698                                                  4698 
4699 values points to the buffer in userspace wher    4699 values points to the buffer in userspace where to store the values.
4700                                                  4700 
4701 This ioctl can fail with -ENOMEM if not enoug    4701 This ioctl can fail with -ENOMEM if not enough memory can be allocated to
4702 complete the task, with -ENXIO if CMMA is not    4702 complete the task, with -ENXIO if CMMA is not enabled, with -EINVAL if
4703 the count field is too large (e.g. more than     4703 the count field is too large (e.g. more than KVM_S390_CMMA_SIZE_MAX) or
4704 if the flags field was not 0, with -EFAULT if    4704 if the flags field was not 0, with -EFAULT if the userspace address is
4705 invalid, if invalid pages are written to (e.g    4705 invalid, if invalid pages are written to (e.g. after the end of memory)
4706 or if no page table is present for the addres    4706 or if no page table is present for the addresses (e.g. when using
4707 hugepages).                                      4707 hugepages).
4708                                                  4708 
4709 4.109 KVM_PPC_GET_CPU_CHAR                       4709 4.109 KVM_PPC_GET_CPU_CHAR
4710 --------------------------                       4710 --------------------------
4711                                                  4711 
4712 :Capability: KVM_CAP_PPC_GET_CPU_CHAR            4712 :Capability: KVM_CAP_PPC_GET_CPU_CHAR
4713 :Architectures: powerpc                          4713 :Architectures: powerpc
4714 :Type: vm ioctl                                  4714 :Type: vm ioctl
4715 :Parameters: struct kvm_ppc_cpu_char (out)       4715 :Parameters: struct kvm_ppc_cpu_char (out)
4716 :Returns: 0 on successful completion,            4716 :Returns: 0 on successful completion,
4717          -EFAULT if struct kvm_ppc_cpu_char c    4717          -EFAULT if struct kvm_ppc_cpu_char cannot be written
4718                                                  4718 
4719 This ioctl gives userspace information about     4719 This ioctl gives userspace information about certain characteristics
4720 of the CPU relating to speculative execution     4720 of the CPU relating to speculative execution of instructions and
4721 possible information leakage resulting from s    4721 possible information leakage resulting from speculative execution (see
4722 CVE-2017-5715, CVE-2017-5753 and CVE-2017-575    4722 CVE-2017-5715, CVE-2017-5753 and CVE-2017-5754).  The information is
4723 returned in struct kvm_ppc_cpu_char, which lo    4723 returned in struct kvm_ppc_cpu_char, which looks like this::
4724                                                  4724 
4725   struct kvm_ppc_cpu_char {                      4725   struct kvm_ppc_cpu_char {
4726         __u64   character;              /* ch    4726         __u64   character;              /* characteristics of the CPU */
4727         __u64   behaviour;              /* re    4727         __u64   behaviour;              /* recommended software behaviour */
4728         __u64   character_mask;         /* va    4728         __u64   character_mask;         /* valid bits in character */
4729         __u64   behaviour_mask;         /* va    4729         __u64   behaviour_mask;         /* valid bits in behaviour */
4730   };                                             4730   };
4731                                                  4731 
4732 For extensibility, the character_mask and beh    4732 For extensibility, the character_mask and behaviour_mask fields
4733 indicate which bits of character and behaviou    4733 indicate which bits of character and behaviour have been filled in by
4734 the kernel.  If the set of defined bits is ex    4734 the kernel.  If the set of defined bits is extended in future then
4735 userspace will be able to tell whether it is     4735 userspace will be able to tell whether it is running on a kernel that
4736 knows about the new bits.                        4736 knows about the new bits.
4737                                                  4737 
4738 The character field describes attributes of t    4738 The character field describes attributes of the CPU which can help
4739 with preventing inadvertent information discl    4739 with preventing inadvertent information disclosure - specifically,
4740 whether there is an instruction to flash-inva    4740 whether there is an instruction to flash-invalidate the L1 data cache
4741 (ori 30,30,0 or mtspr SPRN_TRIG2,rN), whether    4741 (ori 30,30,0 or mtspr SPRN_TRIG2,rN), whether the L1 data cache is set
4742 to a mode where entries can only be used by t    4742 to a mode where entries can only be used by the thread that created
4743 them, whether the bcctr[l] instruction preven    4743 them, whether the bcctr[l] instruction prevents speculation, and
4744 whether a speculation barrier instruction (or    4744 whether a speculation barrier instruction (ori 31,31,0) is provided.
4745                                                  4745 
4746 The behaviour field describes actions that so    4746 The behaviour field describes actions that software should take to
4747 prevent inadvertent information disclosure, a    4747 prevent inadvertent information disclosure, and thus describes which
4748 vulnerabilities the hardware is subject to; s    4748 vulnerabilities the hardware is subject to; specifically whether the
4749 L1 data cache should be flushed when returnin    4749 L1 data cache should be flushed when returning to user mode from the
4750 kernel, and whether a speculation barrier sho    4750 kernel, and whether a speculation barrier should be placed between an
4751 array bounds check and the array access.         4751 array bounds check and the array access.
4752                                                  4752 
4753 These fields use the same bit definitions as     4753 These fields use the same bit definitions as the new
4754 H_GET_CPU_CHARACTERISTICS hypercall.             4754 H_GET_CPU_CHARACTERISTICS hypercall.
4755                                                  4755 
4756 4.110 KVM_MEMORY_ENCRYPT_OP                      4756 4.110 KVM_MEMORY_ENCRYPT_OP
4757 ---------------------------                      4757 ---------------------------
4758                                                  4758 
4759 :Capability: basic                               4759 :Capability: basic
4760 :Architectures: x86                              4760 :Architectures: x86
4761 :Type: vm                                        4761 :Type: vm
4762 :Parameters: an opaque platform specific stru    4762 :Parameters: an opaque platform specific structure (in/out)
4763 :Returns: 0 on success; -1 on error              4763 :Returns: 0 on success; -1 on error
4764                                                  4764 
4765 If the platform supports creating encrypted V    4765 If the platform supports creating encrypted VMs then this ioctl can be used
4766 for issuing platform-specific memory encrypti    4766 for issuing platform-specific memory encryption commands to manage those
4767 encrypted VMs.                                   4767 encrypted VMs.
4768                                                  4768 
4769 Currently, this ioctl is used for issuing Sec    4769 Currently, this ioctl is used for issuing Secure Encrypted Virtualization
4770 (SEV) commands on AMD Processors. The SEV com    4770 (SEV) commands on AMD Processors. The SEV commands are defined in
4771 Documentation/virt/kvm/x86/amd-memory-encrypt    4771 Documentation/virt/kvm/x86/amd-memory-encryption.rst.
4772                                                  4772 
4773 4.111 KVM_MEMORY_ENCRYPT_REG_REGION              4773 4.111 KVM_MEMORY_ENCRYPT_REG_REGION
4774 -----------------------------------              4774 -----------------------------------
4775                                                  4775 
4776 :Capability: basic                               4776 :Capability: basic
4777 :Architectures: x86                              4777 :Architectures: x86
4778 :Type: system                                    4778 :Type: system
4779 :Parameters: struct kvm_enc_region (in)          4779 :Parameters: struct kvm_enc_region (in)
4780 :Returns: 0 on success; -1 on error              4780 :Returns: 0 on success; -1 on error
4781                                                  4781 
4782 This ioctl can be used to register a guest me    4782 This ioctl can be used to register a guest memory region which may
4783 contain encrypted data (e.g. guest RAM, SMRAM    4783 contain encrypted data (e.g. guest RAM, SMRAM etc).
4784                                                  4784 
4785 It is used in the SEV-enabled guest. When enc    4785 It is used in the SEV-enabled guest. When encryption is enabled, a guest
4786 memory region may contain encrypted data. The    4786 memory region may contain encrypted data. The SEV memory encryption
4787 engine uses a tweak such that two identical p    4787 engine uses a tweak such that two identical plaintext pages, each at
4788 different locations will have differing ciphe    4788 different locations will have differing ciphertexts. So swapping or
4789 moving ciphertext of those pages will not res    4789 moving ciphertext of those pages will not result in plaintext being
4790 swapped. So relocating (or migrating) physica    4790 swapped. So relocating (or migrating) physical backing pages for the SEV
4791 guest will require some additional steps.        4791 guest will require some additional steps.
4792                                                  4792 
4793 Note: The current SEV key management spec doe    4793 Note: The current SEV key management spec does not provide commands to
4794 swap or migrate (move) ciphertext pages. Henc    4794 swap or migrate (move) ciphertext pages. Hence, for now we pin the guest
4795 memory region registered with the ioctl.         4795 memory region registered with the ioctl.
4796                                                  4796 
4797 4.112 KVM_MEMORY_ENCRYPT_UNREG_REGION            4797 4.112 KVM_MEMORY_ENCRYPT_UNREG_REGION
4798 -------------------------------------            4798 -------------------------------------
4799                                                  4799 
4800 :Capability: basic                               4800 :Capability: basic
4801 :Architectures: x86                              4801 :Architectures: x86
4802 :Type: system                                    4802 :Type: system
4803 :Parameters: struct kvm_enc_region (in)          4803 :Parameters: struct kvm_enc_region (in)
4804 :Returns: 0 on success; -1 on error              4804 :Returns: 0 on success; -1 on error
4805                                                  4805 
4806 This ioctl can be used to unregister the gues    4806 This ioctl can be used to unregister the guest memory region registered
4807 with KVM_MEMORY_ENCRYPT_REG_REGION ioctl abov    4807 with KVM_MEMORY_ENCRYPT_REG_REGION ioctl above.
4808                                                  4808 
4809 4.113 KVM_HYPERV_EVENTFD                         4809 4.113 KVM_HYPERV_EVENTFD
4810 ------------------------                         4810 ------------------------
4811                                                  4811 
4812 :Capability: KVM_CAP_HYPERV_EVENTFD              4812 :Capability: KVM_CAP_HYPERV_EVENTFD
4813 :Architectures: x86                              4813 :Architectures: x86
4814 :Type: vm ioctl                                  4814 :Type: vm ioctl
4815 :Parameters: struct kvm_hyperv_eventfd (in)      4815 :Parameters: struct kvm_hyperv_eventfd (in)
4816                                                  4816 
4817 This ioctl (un)registers an eventfd to receiv    4817 This ioctl (un)registers an eventfd to receive notifications from the guest on
4818 the specified Hyper-V connection id through t    4818 the specified Hyper-V connection id through the SIGNAL_EVENT hypercall, without
4819 causing a user exit.  SIGNAL_EVENT hypercall     4819 causing a user exit.  SIGNAL_EVENT hypercall with non-zero event flag number
4820 (bits 24-31) still triggers a KVM_EXIT_HYPERV    4820 (bits 24-31) still triggers a KVM_EXIT_HYPERV_HCALL user exit.
4821                                                  4821 
4822 ::                                               4822 ::
4823                                                  4823 
4824   struct kvm_hyperv_eventfd {                    4824   struct kvm_hyperv_eventfd {
4825         __u32 conn_id;                           4825         __u32 conn_id;
4826         __s32 fd;                                4826         __s32 fd;
4827         __u32 flags;                             4827         __u32 flags;
4828         __u32 padding[3];                        4828         __u32 padding[3];
4829   };                                             4829   };
4830                                                  4830 
4831 The conn_id field should fit within 24 bits::    4831 The conn_id field should fit within 24 bits::
4832                                                  4832 
4833   #define KVM_HYPERV_CONN_ID_MASK                4833   #define KVM_HYPERV_CONN_ID_MASK               0x00ffffff
4834                                                  4834 
4835 The acceptable values for the flags field are    4835 The acceptable values for the flags field are::
4836                                                  4836 
4837   #define KVM_HYPERV_EVENTFD_DEASSIGN   (1 <<    4837   #define KVM_HYPERV_EVENTFD_DEASSIGN   (1 << 0)
4838                                                  4838 
4839 :Returns: 0 on success,                          4839 :Returns: 0 on success,
4840           -EINVAL if conn_id or flags is outs    4840           -EINVAL if conn_id or flags is outside the allowed range,
4841           -ENOENT on deassign if the conn_id     4841           -ENOENT on deassign if the conn_id isn't registered,
4842           -EEXIST on assign if the conn_id is    4842           -EEXIST on assign if the conn_id is already registered
4843                                                  4843 
4844 4.114 KVM_GET_NESTED_STATE                       4844 4.114 KVM_GET_NESTED_STATE
4845 --------------------------                       4845 --------------------------
4846                                                  4846 
4847 :Capability: KVM_CAP_NESTED_STATE                4847 :Capability: KVM_CAP_NESTED_STATE
4848 :Architectures: x86                              4848 :Architectures: x86
4849 :Type: vcpu ioctl                                4849 :Type: vcpu ioctl
4850 :Parameters: struct kvm_nested_state (in/out)    4850 :Parameters: struct kvm_nested_state (in/out)
4851 :Returns: 0 on success, -1 on error              4851 :Returns: 0 on success, -1 on error
4852                                                  4852 
4853 Errors:                                          4853 Errors:
4854                                                  4854 
4855   =====      ================================    4855   =====      =============================================================
4856   E2BIG      the total state size exceeds the    4856   E2BIG      the total state size exceeds the value of 'size' specified by
4857              the user; the size required will    4857              the user; the size required will be written into size.
4858   =====      ================================    4858   =====      =============================================================
4859                                                  4859 
4860 ::                                               4860 ::
4861                                                  4861 
4862   struct kvm_nested_state {                      4862   struct kvm_nested_state {
4863         __u16 flags;                             4863         __u16 flags;
4864         __u16 format;                            4864         __u16 format;
4865         __u32 size;                              4865         __u32 size;
4866                                                  4866 
4867         union {                                  4867         union {
4868                 struct kvm_vmx_nested_state_h    4868                 struct kvm_vmx_nested_state_hdr vmx;
4869                 struct kvm_svm_nested_state_h    4869                 struct kvm_svm_nested_state_hdr svm;
4870                                                  4870 
4871                 /* Pad the header to 128 byte    4871                 /* Pad the header to 128 bytes.  */
4872                 __u8 pad[120];                   4872                 __u8 pad[120];
4873         } hdr;                                   4873         } hdr;
4874                                                  4874 
4875         union {                                  4875         union {
4876                 struct kvm_vmx_nested_state_d    4876                 struct kvm_vmx_nested_state_data vmx[0];
4877                 struct kvm_svm_nested_state_d    4877                 struct kvm_svm_nested_state_data svm[0];
4878         } data;                                  4878         } data;
4879   };                                             4879   };
4880                                                  4880 
4881   #define KVM_STATE_NESTED_GUEST_MODE            4881   #define KVM_STATE_NESTED_GUEST_MODE           0x00000001
4882   #define KVM_STATE_NESTED_RUN_PENDING           4882   #define KVM_STATE_NESTED_RUN_PENDING          0x00000002
4883   #define KVM_STATE_NESTED_EVMCS                 4883   #define KVM_STATE_NESTED_EVMCS                0x00000004
4884                                                  4884 
4885   #define KVM_STATE_NESTED_FORMAT_VMX            4885   #define KVM_STATE_NESTED_FORMAT_VMX           0
4886   #define KVM_STATE_NESTED_FORMAT_SVM            4886   #define KVM_STATE_NESTED_FORMAT_SVM           1
4887                                                  4887 
4888   #define KVM_STATE_NESTED_VMX_VMCS_SIZE         4888   #define KVM_STATE_NESTED_VMX_VMCS_SIZE        0x1000
4889                                                  4889 
4890   #define KVM_STATE_NESTED_VMX_SMM_GUEST_MODE    4890   #define KVM_STATE_NESTED_VMX_SMM_GUEST_MODE   0x00000001
4891   #define KVM_STATE_NESTED_VMX_SMM_VMXON         4891   #define KVM_STATE_NESTED_VMX_SMM_VMXON        0x00000002
4892                                                  4892 
4893   #define KVM_STATE_VMX_PREEMPTION_TIMER_DEAD    4893   #define KVM_STATE_VMX_PREEMPTION_TIMER_DEADLINE 0x00000001
4894                                                  4894 
4895   struct kvm_vmx_nested_state_hdr {              4895   struct kvm_vmx_nested_state_hdr {
4896         __u64 vmxon_pa;                          4896         __u64 vmxon_pa;
4897         __u64 vmcs12_pa;                         4897         __u64 vmcs12_pa;
4898                                                  4898 
4899         struct {                                 4899         struct {
4900                 __u16 flags;                     4900                 __u16 flags;
4901         } smm;                                   4901         } smm;
4902                                                  4902 
4903         __u32 flags;                             4903         __u32 flags;
4904         __u64 preemption_timer_deadline;         4904         __u64 preemption_timer_deadline;
4905   };                                             4905   };
4906                                                  4906 
4907   struct kvm_vmx_nested_state_data {             4907   struct kvm_vmx_nested_state_data {
4908         __u8 vmcs12[KVM_STATE_NESTED_VMX_VMCS    4908         __u8 vmcs12[KVM_STATE_NESTED_VMX_VMCS_SIZE];
4909         __u8 shadow_vmcs12[KVM_STATE_NESTED_V    4909         __u8 shadow_vmcs12[KVM_STATE_NESTED_VMX_VMCS_SIZE];
4910   };                                             4910   };
4911                                                  4911 
4912 This ioctl copies the vcpu's nested virtualiz    4912 This ioctl copies the vcpu's nested virtualization state from the kernel to
4913 userspace.                                       4913 userspace.
4914                                                  4914 
4915 The maximum size of the state can be retrieve    4915 The maximum size of the state can be retrieved by passing KVM_CAP_NESTED_STATE
4916 to the KVM_CHECK_EXTENSION ioctl().              4916 to the KVM_CHECK_EXTENSION ioctl().
4917                                                  4917 
4918 4.115 KVM_SET_NESTED_STATE                       4918 4.115 KVM_SET_NESTED_STATE
4919 --------------------------                       4919 --------------------------
4920                                                  4920 
4921 :Capability: KVM_CAP_NESTED_STATE                4921 :Capability: KVM_CAP_NESTED_STATE
4922 :Architectures: x86                              4922 :Architectures: x86
4923 :Type: vcpu ioctl                                4923 :Type: vcpu ioctl
4924 :Parameters: struct kvm_nested_state (in)        4924 :Parameters: struct kvm_nested_state (in)
4925 :Returns: 0 on success, -1 on error              4925 :Returns: 0 on success, -1 on error
4926                                                  4926 
4927 This copies the vcpu's kvm_nested_state struc    4927 This copies the vcpu's kvm_nested_state struct from userspace to the kernel.
4928 For the definition of struct kvm_nested_state    4928 For the definition of struct kvm_nested_state, see KVM_GET_NESTED_STATE.
4929                                                  4929 
4930 4.116 KVM_(UN)REGISTER_COALESCED_MMIO            4930 4.116 KVM_(UN)REGISTER_COALESCED_MMIO
4931 -------------------------------------            4931 -------------------------------------
4932                                                  4932 
4933 :Capability: KVM_CAP_COALESCED_MMIO (for coal    4933 :Capability: KVM_CAP_COALESCED_MMIO (for coalesced mmio)
4934              KVM_CAP_COALESCED_PIO (for coale    4934              KVM_CAP_COALESCED_PIO (for coalesced pio)
4935 :Architectures: all                              4935 :Architectures: all
4936 :Type: vm ioctl                                  4936 :Type: vm ioctl
4937 :Parameters: struct kvm_coalesced_mmio_zone      4937 :Parameters: struct kvm_coalesced_mmio_zone
4938 :Returns: 0 on success, < 0 on error             4938 :Returns: 0 on success, < 0 on error
4939                                                  4939 
4940 Coalesced I/O is a performance optimization t    4940 Coalesced I/O is a performance optimization that defers hardware
4941 register write emulation so that userspace ex    4941 register write emulation so that userspace exits are avoided.  It is
4942 typically used to reduce the overhead of emul    4942 typically used to reduce the overhead of emulating frequently accessed
4943 hardware registers.                              4943 hardware registers.
4944                                                  4944 
4945 When a hardware register is configured for co    4945 When a hardware register is configured for coalesced I/O, write accesses
4946 do not exit to userspace and their value is r    4946 do not exit to userspace and their value is recorded in a ring buffer
4947 that is shared between kernel and userspace.     4947 that is shared between kernel and userspace.
4948                                                  4948 
4949 Coalesced I/O is used if one or more write ac    4949 Coalesced I/O is used if one or more write accesses to a hardware
4950 register can be deferred until a read or a wr    4950 register can be deferred until a read or a write to another hardware
4951 register on the same device.  This last acces    4951 register on the same device.  This last access will cause a vmexit and
4952 userspace will process accesses from the ring    4952 userspace will process accesses from the ring buffer before emulating
4953 it. That will avoid exiting to userspace on r    4953 it. That will avoid exiting to userspace on repeated writes.
4954                                                  4954 
4955 Coalesced pio is based on coalesced mmio. The    4955 Coalesced pio is based on coalesced mmio. There is little difference
4956 between coalesced mmio and pio except that co    4956 between coalesced mmio and pio except that coalesced pio records accesses
4957 to I/O ports.                                    4957 to I/O ports.
4958                                                  4958 
4959 4.117 KVM_CLEAR_DIRTY_LOG (vm ioctl)             4959 4.117 KVM_CLEAR_DIRTY_LOG (vm ioctl)
4960 ------------------------------------             4960 ------------------------------------
4961                                                  4961 
4962 :Capability: KVM_CAP_MANUAL_DIRTY_LOG_PROTECT    4962 :Capability: KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2
4963 :Architectures: x86, arm64, mips                 4963 :Architectures: x86, arm64, mips
4964 :Type: vm ioctl                                  4964 :Type: vm ioctl
4965 :Parameters: struct kvm_clear_dirty_log (in)     4965 :Parameters: struct kvm_clear_dirty_log (in)
4966 :Returns: 0 on success, -1 on error              4966 :Returns: 0 on success, -1 on error
4967                                                  4967 
4968 ::                                               4968 ::
4969                                                  4969 
4970   /* for KVM_CLEAR_DIRTY_LOG */                  4970   /* for KVM_CLEAR_DIRTY_LOG */
4971   struct kvm_clear_dirty_log {                   4971   struct kvm_clear_dirty_log {
4972         __u32 slot;                              4972         __u32 slot;
4973         __u32 num_pages;                         4973         __u32 num_pages;
4974         __u64 first_page;                        4974         __u64 first_page;
4975         union {                                  4975         union {
4976                 void __user *dirty_bitmap; /*    4976                 void __user *dirty_bitmap; /* one bit per page */
4977                 __u64 padding;                   4977                 __u64 padding;
4978         };                                       4978         };
4979   };                                             4979   };
4980                                                  4980 
4981 The ioctl clears the dirty status of pages in    4981 The ioctl clears the dirty status of pages in a memory slot, according to
4982 the bitmap that is passed in struct kvm_clear    4982 the bitmap that is passed in struct kvm_clear_dirty_log's dirty_bitmap
4983 field.  Bit 0 of the bitmap corresponds to pa    4983 field.  Bit 0 of the bitmap corresponds to page "first_page" in the
4984 memory slot, and num_pages is the size in bit    4984 memory slot, and num_pages is the size in bits of the input bitmap.
4985 first_page must be a multiple of 64; num_page    4985 first_page must be a multiple of 64; num_pages must also be a multiple of
4986 64 unless first_page + num_pages is the size     4986 64 unless first_page + num_pages is the size of the memory slot.  For each
4987 bit that is set in the input bitmap, the corr    4987 bit that is set in the input bitmap, the corresponding page is marked "clean"
4988 in KVM's dirty bitmap, and dirty tracking is     4988 in KVM's dirty bitmap, and dirty tracking is re-enabled for that page
4989 (for example via write-protection, or by clea    4989 (for example via write-protection, or by clearing the dirty bit in
4990 a page table entry).                             4990 a page table entry).
4991                                                  4991 
4992 If KVM_CAP_MULTI_ADDRESS_SPACE is available,     4992 If KVM_CAP_MULTI_ADDRESS_SPACE is available, bits 16-31 of slot field specifies
4993 the address space for which you want to clear    4993 the address space for which you want to clear the dirty status.  See
4994 KVM_SET_USER_MEMORY_REGION for details on the    4994 KVM_SET_USER_MEMORY_REGION for details on the usage of slot field.
4995                                                  4995 
4996 This ioctl is mostly useful when KVM_CAP_MANU    4996 This ioctl is mostly useful when KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2
4997 is enabled; for more information, see the des    4997 is enabled; for more information, see the description of the capability.
4998 However, it can always be used as long as KVM    4998 However, it can always be used as long as KVM_CHECK_EXTENSION confirms
4999 that KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is pre    4999 that KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 is present.
5000                                                  5000 
5001 4.118 KVM_GET_SUPPORTED_HV_CPUID                 5001 4.118 KVM_GET_SUPPORTED_HV_CPUID
5002 --------------------------------                 5002 --------------------------------
5003                                                  5003 
5004 :Capability: KVM_CAP_HYPERV_CPUID (vcpu), KVM    5004 :Capability: KVM_CAP_HYPERV_CPUID (vcpu), KVM_CAP_SYS_HYPERV_CPUID (system)
5005 :Architectures: x86                              5005 :Architectures: x86
5006 :Type: system ioctl, vcpu ioctl                  5006 :Type: system ioctl, vcpu ioctl
5007 :Parameters: struct kvm_cpuid2 (in/out)          5007 :Parameters: struct kvm_cpuid2 (in/out)
5008 :Returns: 0 on success, -1 on error              5008 :Returns: 0 on success, -1 on error
5009                                                  5009 
5010 ::                                               5010 ::
5011                                                  5011 
5012   struct kvm_cpuid2 {                            5012   struct kvm_cpuid2 {
5013         __u32 nent;                              5013         __u32 nent;
5014         __u32 padding;                           5014         __u32 padding;
5015         struct kvm_cpuid_entry2 entries[0];      5015         struct kvm_cpuid_entry2 entries[0];
5016   };                                             5016   };
5017                                                  5017 
5018   struct kvm_cpuid_entry2 {                      5018   struct kvm_cpuid_entry2 {
5019         __u32 function;                          5019         __u32 function;
5020         __u32 index;                             5020         __u32 index;
5021         __u32 flags;                             5021         __u32 flags;
5022         __u32 eax;                               5022         __u32 eax;
5023         __u32 ebx;                               5023         __u32 ebx;
5024         __u32 ecx;                               5024         __u32 ecx;
5025         __u32 edx;                               5025         __u32 edx;
5026         __u32 padding[3];                        5026         __u32 padding[3];
5027   };                                             5027   };
5028                                                  5028 
5029 This ioctl returns x86 cpuid features leaves     5029 This ioctl returns x86 cpuid features leaves related to Hyper-V emulation in
5030 KVM.  Userspace can use the information retur    5030 KVM.  Userspace can use the information returned by this ioctl to construct
5031 cpuid information presented to guests consumi    5031 cpuid information presented to guests consuming Hyper-V enlightenments (e.g.
5032 Windows or Hyper-V guests).                      5032 Windows or Hyper-V guests).
5033                                                  5033 
5034 CPUID feature leaves returned by this ioctl a    5034 CPUID feature leaves returned by this ioctl are defined by Hyper-V Top Level
5035 Functional Specification (TLFS). These leaves    5035 Functional Specification (TLFS). These leaves can't be obtained with
5036 KVM_GET_SUPPORTED_CPUID ioctl because some of    5036 KVM_GET_SUPPORTED_CPUID ioctl because some of them intersect with KVM feature
5037 leaves (0x40000000, 0x40000001).                 5037 leaves (0x40000000, 0x40000001).
5038                                                  5038 
5039 Currently, the following list of CPUID leaves    5039 Currently, the following list of CPUID leaves are returned:
5040                                                  5040 
5041  - HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS         5041  - HYPERV_CPUID_VENDOR_AND_MAX_FUNCTIONS
5042  - HYPERV_CPUID_INTERFACE                        5042  - HYPERV_CPUID_INTERFACE
5043  - HYPERV_CPUID_VERSION                          5043  - HYPERV_CPUID_VERSION
5044  - HYPERV_CPUID_FEATURES                         5044  - HYPERV_CPUID_FEATURES
5045  - HYPERV_CPUID_ENLIGHTMENT_INFO                 5045  - HYPERV_CPUID_ENLIGHTMENT_INFO
5046  - HYPERV_CPUID_IMPLEMENT_LIMITS                 5046  - HYPERV_CPUID_IMPLEMENT_LIMITS
5047  - HYPERV_CPUID_NESTED_FEATURES                  5047  - HYPERV_CPUID_NESTED_FEATURES
5048  - HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIO    5048  - HYPERV_CPUID_SYNDBG_VENDOR_AND_MAX_FUNCTIONS
5049  - HYPERV_CPUID_SYNDBG_INTERFACE                 5049  - HYPERV_CPUID_SYNDBG_INTERFACE
5050  - HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES     5050  - HYPERV_CPUID_SYNDBG_PLATFORM_CAPABILITIES
5051                                                  5051 
5052 Userspace invokes KVM_GET_SUPPORTED_HV_CPUID     5052 Userspace invokes KVM_GET_SUPPORTED_HV_CPUID by passing a kvm_cpuid2 structure
5053 with the 'nent' field indicating the number o    5053 with the 'nent' field indicating the number of entries in the variable-size
5054 array 'entries'.  If the number of entries is    5054 array 'entries'.  If the number of entries is too low to describe all Hyper-V
5055 feature leaves, an error (E2BIG) is returned.    5055 feature leaves, an error (E2BIG) is returned. If the number is more or equal
5056 to the number of Hyper-V feature leaves, the     5056 to the number of Hyper-V feature leaves, the 'nent' field is adjusted to the
5057 number of valid entries in the 'entries' arra    5057 number of valid entries in the 'entries' array, which is then filled.
5058                                                  5058 
5059 'index' and 'flags' fields in 'struct kvm_cpu    5059 'index' and 'flags' fields in 'struct kvm_cpuid_entry2' are currently reserved,
5060 userspace should not expect to get any partic    5060 userspace should not expect to get any particular value there.
5061                                                  5061 
5062 Note, vcpu version of KVM_GET_SUPPORTED_HV_CP    5062 Note, vcpu version of KVM_GET_SUPPORTED_HV_CPUID is currently deprecated. Unlike
5063 system ioctl which exposes all supported feat    5063 system ioctl which exposes all supported feature bits unconditionally, vcpu
5064 version has the following quirks:                5064 version has the following quirks:
5065                                                  5065 
5066 - HYPERV_CPUID_NESTED_FEATURES leaf and HV_X6    5066 - HYPERV_CPUID_NESTED_FEATURES leaf and HV_X64_ENLIGHTENED_VMCS_RECOMMENDED
5067   feature bit are only exposed when Enlighten    5067   feature bit are only exposed when Enlightened VMCS was previously enabled
5068   on the corresponding vCPU (KVM_CAP_HYPERV_E    5068   on the corresponding vCPU (KVM_CAP_HYPERV_ENLIGHTENED_VMCS).
5069 - HV_STIMER_DIRECT_MODE_AVAILABLE bit is only    5069 - HV_STIMER_DIRECT_MODE_AVAILABLE bit is only exposed with in-kernel LAPIC.
5070   (presumes KVM_CREATE_IRQCHIP has already be    5070   (presumes KVM_CREATE_IRQCHIP has already been called).
5071                                                  5071 
5072 4.119 KVM_ARM_VCPU_FINALIZE                      5072 4.119 KVM_ARM_VCPU_FINALIZE
5073 ---------------------------                      5073 ---------------------------
5074                                                  5074 
5075 :Architectures: arm64                            5075 :Architectures: arm64
5076 :Type: vcpu ioctl                                5076 :Type: vcpu ioctl
5077 :Parameters: int feature (in)                    5077 :Parameters: int feature (in)
5078 :Returns: 0 on success, -1 on error              5078 :Returns: 0 on success, -1 on error
5079                                                  5079 
5080 Errors:                                          5080 Errors:
5081                                                  5081 
5082   ======     ================================    5082   ======     ==============================================================
5083   EPERM      feature not enabled, needs confi    5083   EPERM      feature not enabled, needs configuration, or already finalized
5084   EINVAL     feature unknown or not present      5084   EINVAL     feature unknown or not present
5085   ======     ================================    5085   ======     ==============================================================
5086                                                  5086 
5087 Recognised values for feature:                   5087 Recognised values for feature:
5088                                                  5088 
5089   =====      ================================    5089   =====      ===========================================
5090   arm64      KVM_ARM_VCPU_SVE (requires KVM_C    5090   arm64      KVM_ARM_VCPU_SVE (requires KVM_CAP_ARM_SVE)
5091   =====      ================================    5091   =====      ===========================================
5092                                                  5092 
5093 Finalizes the configuration of the specified     5093 Finalizes the configuration of the specified vcpu feature.
5094                                                  5094 
5095 The vcpu must already have been initialised,     5095 The vcpu must already have been initialised, enabling the affected feature, by
5096 means of a successful KVM_ARM_VCPU_INIT call     5096 means of a successful KVM_ARM_VCPU_INIT call with the appropriate flag set in
5097 features[].                                      5097 features[].
5098                                                  5098 
5099 For affected vcpu features, this is a mandato    5099 For affected vcpu features, this is a mandatory step that must be performed
5100 before the vcpu is fully usable.                 5100 before the vcpu is fully usable.
5101                                                  5101 
5102 Between KVM_ARM_VCPU_INIT and KVM_ARM_VCPU_FI    5102 Between KVM_ARM_VCPU_INIT and KVM_ARM_VCPU_FINALIZE, the feature may be
5103 configured by use of ioctls such as KVM_SET_O    5103 configured by use of ioctls such as KVM_SET_ONE_REG.  The exact configuration
5104 that should be performed and how to do it are    5104 that should be performed and how to do it are feature-dependent.
5105                                                  5105 
5106 Other calls that depend on a particular featu    5106 Other calls that depend on a particular feature being finalized, such as
5107 KVM_RUN, KVM_GET_REG_LIST, KVM_GET_ONE_REG an    5107 KVM_RUN, KVM_GET_REG_LIST, KVM_GET_ONE_REG and KVM_SET_ONE_REG, will fail with
5108 -EPERM unless the feature has already been fi    5108 -EPERM unless the feature has already been finalized by means of a
5109 KVM_ARM_VCPU_FINALIZE call.                      5109 KVM_ARM_VCPU_FINALIZE call.
5110                                                  5110 
5111 See KVM_ARM_VCPU_INIT for details of vcpu fea    5111 See KVM_ARM_VCPU_INIT for details of vcpu features that require finalization
5112 using this ioctl.                                5112 using this ioctl.
5113                                                  5113 
5114 4.120 KVM_SET_PMU_EVENT_FILTER                   5114 4.120 KVM_SET_PMU_EVENT_FILTER
5115 ------------------------------                   5115 ------------------------------
5116                                                  5116 
5117 :Capability: KVM_CAP_PMU_EVENT_FILTER            5117 :Capability: KVM_CAP_PMU_EVENT_FILTER
5118 :Architectures: x86                              5118 :Architectures: x86
5119 :Type: vm ioctl                                  5119 :Type: vm ioctl
5120 :Parameters: struct kvm_pmu_event_filter (in)    5120 :Parameters: struct kvm_pmu_event_filter (in)
5121 :Returns: 0 on success, -1 on error              5121 :Returns: 0 on success, -1 on error
5122                                                  5122 
5123 Errors:                                          5123 Errors:
5124                                                  5124 
5125   ======     ================================    5125   ======     ============================================================
5126   EFAULT     args[0] cannot be accessed          5126   EFAULT     args[0] cannot be accessed
5127   EINVAL     args[0] contains invalid data in    5127   EINVAL     args[0] contains invalid data in the filter or filter events
5128   E2BIG      nevents is too large                5128   E2BIG      nevents is too large
5129   EBUSY      not enough memory to allocate th    5129   EBUSY      not enough memory to allocate the filter
5130   ======     ================================    5130   ======     ============================================================
5131                                                  5131 
5132 ::                                               5132 ::
5133                                                  5133 
5134   struct kvm_pmu_event_filter {                  5134   struct kvm_pmu_event_filter {
5135         __u32 action;                            5135         __u32 action;
5136         __u32 nevents;                           5136         __u32 nevents;
5137         __u32 fixed_counter_bitmap;              5137         __u32 fixed_counter_bitmap;
5138         __u32 flags;                             5138         __u32 flags;
5139         __u32 pad[4];                            5139         __u32 pad[4];
5140         __u64 events[0];                         5140         __u64 events[0];
5141   };                                             5141   };
5142                                                  5142 
5143 This ioctl restricts the set of PMU events th    5143 This ioctl restricts the set of PMU events the guest can program by limiting
5144 which event select and unit mask combinations    5144 which event select and unit mask combinations are permitted.
5145                                                  5145 
5146 The argument holds a list of filter events wh    5146 The argument holds a list of filter events which will be allowed or denied.
5147                                                  5147 
5148 Filter events only control general purpose co    5148 Filter events only control general purpose counters; fixed purpose counters
5149 are controlled by the fixed_counter_bitmap.      5149 are controlled by the fixed_counter_bitmap.
5150                                                  5150 
5151 Valid values for 'flags'::                       5151 Valid values for 'flags'::
5152                                                  5152 
5153 ``0``                                            5153 ``0``
5154                                                  5154 
5155 To use this mode, clear the 'flags' field.       5155 To use this mode, clear the 'flags' field.
5156                                                  5156 
5157 In this mode each event will contain an event    5157 In this mode each event will contain an event select + unit mask.
5158                                                  5158 
5159 When the guest attempts to program the PMU th    5159 When the guest attempts to program the PMU the guest's event select +
5160 unit mask is compared against the filter even    5160 unit mask is compared against the filter events to determine whether the
5161 guest should have access.                        5161 guest should have access.
5162                                                  5162 
5163 ``KVM_PMU_EVENT_FLAG_MASKED_EVENTS``             5163 ``KVM_PMU_EVENT_FLAG_MASKED_EVENTS``
5164 :Capability: KVM_CAP_PMU_EVENT_MASKED_EVENTS     5164 :Capability: KVM_CAP_PMU_EVENT_MASKED_EVENTS
5165                                                  5165 
5166 In this mode each filter event will contain a    5166 In this mode each filter event will contain an event select, mask, match, and
5167 exclude value.  To encode a masked event use:    5167 exclude value.  To encode a masked event use::
5168                                                  5168 
5169   KVM_PMU_ENCODE_MASKED_ENTRY()                  5169   KVM_PMU_ENCODE_MASKED_ENTRY()
5170                                                  5170 
5171 An encoded event will follow this layout::       5171 An encoded event will follow this layout::
5172                                                  5172 
5173   Bits   Description                             5173   Bits   Description
5174   ----   -----------                             5174   ----   -----------
5175   7:0    event select (low bits)                 5175   7:0    event select (low bits)
5176   15:8   umask match                             5176   15:8   umask match
5177   31:16  unused                                  5177   31:16  unused
5178   35:32  event select (high bits)                5178   35:32  event select (high bits)
5179   36:54  unused                                  5179   36:54  unused
5180   55     exclude bit                             5180   55     exclude bit
5181   63:56  umask mask                              5181   63:56  umask mask
5182                                                  5182 
5183 When the guest attempts to program the PMU, t    5183 When the guest attempts to program the PMU, these steps are followed in
5184 determining if the guest should have access:     5184 determining if the guest should have access:
5185                                                  5185 
5186  1. Match the event select from the guest aga    5186  1. Match the event select from the guest against the filter events.
5187  2. If a match is found, match the guest's un    5187  2. If a match is found, match the guest's unit mask to the mask and match
5188     values of the included filter events.        5188     values of the included filter events.
5189     I.e. (unit mask & mask) == match && !excl    5189     I.e. (unit mask & mask) == match && !exclude.
5190  3. If a match is found, match the guest's un    5190  3. If a match is found, match the guest's unit mask to the mask and match
5191     values of the excluded filter events.        5191     values of the excluded filter events.
5192     I.e. (unit mask & mask) == match && exclu    5192     I.e. (unit mask & mask) == match && exclude.
5193  4.                                              5193  4.
5194    a. If an included match is found and an ex    5194    a. If an included match is found and an excluded match is not found, filter
5195       the event.                                 5195       the event.
5196    b. For everything else, do not filter the     5196    b. For everything else, do not filter the event.
5197  5.                                              5197  5.
5198    a. If the event is filtered and it's an al    5198    a. If the event is filtered and it's an allow list, allow the guest to
5199       program the event.                         5199       program the event.
5200    b. If the event is filtered and it's a den    5200    b. If the event is filtered and it's a deny list, do not allow the guest to
5201       program the event.                         5201       program the event.
5202                                                  5202 
5203 When setting a new pmu event filter, -EINVAL     5203 When setting a new pmu event filter, -EINVAL will be returned if any of the
5204 unused fields are set or if any of the high b    5204 unused fields are set or if any of the high bits (35:32) in the event
5205 select are set when called on Intel.             5205 select are set when called on Intel.
5206                                                  5206 
5207 Valid values for 'action'::                      5207 Valid values for 'action'::
5208                                                  5208 
5209   #define KVM_PMU_EVENT_ALLOW 0                  5209   #define KVM_PMU_EVENT_ALLOW 0
5210   #define KVM_PMU_EVENT_DENY 1                   5210   #define KVM_PMU_EVENT_DENY 1
5211                                                  5211 
5212 Via this API, KVM userspace can also control     5212 Via this API, KVM userspace can also control the behavior of the VM's fixed
5213 counters (if any) by configuring the "action"    5213 counters (if any) by configuring the "action" and "fixed_counter_bitmap" fields.
5214                                                  5214 
5215 Specifically, KVM follows the following pseud    5215 Specifically, KVM follows the following pseudo-code when determining whether to
5216 allow the guest FixCtr[i] to count its pre-de    5216 allow the guest FixCtr[i] to count its pre-defined fixed event::
5217                                                  5217 
5218   FixCtr[i]_is_allowed = (action == ALLOW) &&    5218   FixCtr[i]_is_allowed = (action == ALLOW) && (bitmap & BIT(i)) ||
5219     (action == DENY) && !(bitmap & BIT(i));      5219     (action == DENY) && !(bitmap & BIT(i));
5220   FixCtr[i]_is_denied = !FixCtr[i]_is_allowed    5220   FixCtr[i]_is_denied = !FixCtr[i]_is_allowed;
5221                                                  5221 
5222 KVM always consumes fixed_counter_bitmap, it'    5222 KVM always consumes fixed_counter_bitmap, it's userspace's responsibility to
5223 ensure fixed_counter_bitmap is set correctly,    5223 ensure fixed_counter_bitmap is set correctly, e.g. if userspace wants to define
5224 a filter that only affects general purpose co    5224 a filter that only affects general purpose counters.
5225                                                  5225 
5226 Note, the "events" field also applies to fixe    5226 Note, the "events" field also applies to fixed counters' hardcoded event_select
5227 and unit_mask values.  "fixed_counter_bitmap"    5227 and unit_mask values.  "fixed_counter_bitmap" has higher priority than "events"
5228 if there is a contradiction between the two.     5228 if there is a contradiction between the two.
5229                                                  5229 
5230 4.121 KVM_PPC_SVM_OFF                            5230 4.121 KVM_PPC_SVM_OFF
5231 ---------------------                            5231 ---------------------
5232                                                  5232 
5233 :Capability: basic                               5233 :Capability: basic
5234 :Architectures: powerpc                          5234 :Architectures: powerpc
5235 :Type: vm ioctl                                  5235 :Type: vm ioctl
5236 :Parameters: none                                5236 :Parameters: none
5237 :Returns: 0 on successful completion,            5237 :Returns: 0 on successful completion,
5238                                                  5238 
5239 Errors:                                          5239 Errors:
5240                                                  5240 
5241   ======     ================================    5241   ======     ================================================================
5242   EINVAL     if ultravisor failed to terminat    5242   EINVAL     if ultravisor failed to terminate the secure guest
5243   ENOMEM     if hypervisor failed to allocate    5243   ENOMEM     if hypervisor failed to allocate new radix page tables for guest
5244   ======     ================================    5244   ======     ================================================================
5245                                                  5245 
5246 This ioctl is used to turn off the secure mod    5246 This ioctl is used to turn off the secure mode of the guest or transition
5247 the guest from secure mode to normal mode. Th    5247 the guest from secure mode to normal mode. This is invoked when the guest
5248 is reset. This has no effect if called for a     5248 is reset. This has no effect if called for a normal guest.
5249                                                  5249 
5250 This ioctl issues an ultravisor call to termi    5250 This ioctl issues an ultravisor call to terminate the secure guest,
5251 unpins the VPA pages and releases all the dev    5251 unpins the VPA pages and releases all the device pages that are used to
5252 track the secure pages by hypervisor.            5252 track the secure pages by hypervisor.
5253                                                  5253 
5254 4.122 KVM_S390_NORMAL_RESET                      5254 4.122 KVM_S390_NORMAL_RESET
5255 ---------------------------                      5255 ---------------------------
5256                                                  5256 
5257 :Capability: KVM_CAP_S390_VCPU_RESETS            5257 :Capability: KVM_CAP_S390_VCPU_RESETS
5258 :Architectures: s390                             5258 :Architectures: s390
5259 :Type: vcpu ioctl                                5259 :Type: vcpu ioctl
5260 :Parameters: none                                5260 :Parameters: none
5261 :Returns: 0                                      5261 :Returns: 0
5262                                                  5262 
5263 This ioctl resets VCPU registers and control     5263 This ioctl resets VCPU registers and control structures according to
5264 the cpu reset definition in the POP (Principl    5264 the cpu reset definition in the POP (Principles Of Operation).
5265                                                  5265 
5266 4.123 KVM_S390_INITIAL_RESET                     5266 4.123 KVM_S390_INITIAL_RESET
5267 ----------------------------                     5267 ----------------------------
5268                                                  5268 
5269 :Capability: none                                5269 :Capability: none
5270 :Architectures: s390                             5270 :Architectures: s390
5271 :Type: vcpu ioctl                                5271 :Type: vcpu ioctl
5272 :Parameters: none                                5272 :Parameters: none
5273 :Returns: 0                                      5273 :Returns: 0
5274                                                  5274 
5275 This ioctl resets VCPU registers and control     5275 This ioctl resets VCPU registers and control structures according to
5276 the initial cpu reset definition in the POP.     5276 the initial cpu reset definition in the POP. However, the cpu is not
5277 put into ESA mode. This reset is a superset o    5277 put into ESA mode. This reset is a superset of the normal reset.
5278                                                  5278 
5279 4.124 KVM_S390_CLEAR_RESET                       5279 4.124 KVM_S390_CLEAR_RESET
5280 --------------------------                       5280 --------------------------
5281                                                  5281 
5282 :Capability: KVM_CAP_S390_VCPU_RESETS            5282 :Capability: KVM_CAP_S390_VCPU_RESETS
5283 :Architectures: s390                             5283 :Architectures: s390
5284 :Type: vcpu ioctl                                5284 :Type: vcpu ioctl
5285 :Parameters: none                                5285 :Parameters: none
5286 :Returns: 0                                      5286 :Returns: 0
5287                                                  5287 
5288 This ioctl resets VCPU registers and control     5288 This ioctl resets VCPU registers and control structures according to
5289 the clear cpu reset definition in the POP. Ho    5289 the clear cpu reset definition in the POP. However, the cpu is not put
5290 into ESA mode. This reset is a superset of th    5290 into ESA mode. This reset is a superset of the initial reset.
5291                                                  5291 
5292                                                  5292 
5293 4.125 KVM_S390_PV_COMMAND                        5293 4.125 KVM_S390_PV_COMMAND
5294 -------------------------                        5294 -------------------------
5295                                                  5295 
5296 :Capability: KVM_CAP_S390_PROTECTED              5296 :Capability: KVM_CAP_S390_PROTECTED
5297 :Architectures: s390                             5297 :Architectures: s390
5298 :Type: vm ioctl                                  5298 :Type: vm ioctl
5299 :Parameters: struct kvm_pv_cmd                   5299 :Parameters: struct kvm_pv_cmd
5300 :Returns: 0 on success, < 0 on error             5300 :Returns: 0 on success, < 0 on error
5301                                                  5301 
5302 ::                                               5302 ::
5303                                                  5303 
5304   struct kvm_pv_cmd {                            5304   struct kvm_pv_cmd {
5305         __u32 cmd;      /* Command to be exec    5305         __u32 cmd;      /* Command to be executed */
5306         __u16 rc;       /* Ultravisor return     5306         __u16 rc;       /* Ultravisor return code */
5307         __u16 rrc;      /* Ultravisor return     5307         __u16 rrc;      /* Ultravisor return reason code */
5308         __u64 data;     /* Data or address */    5308         __u64 data;     /* Data or address */
5309         __u32 flags;    /* flags for future e    5309         __u32 flags;    /* flags for future extensions. Must be 0 for now */
5310         __u32 reserved[3];                       5310         __u32 reserved[3];
5311   };                                             5311   };
5312                                                  5312 
5313 **Ultravisor return codes**                      5313 **Ultravisor return codes**
5314 The Ultravisor return (reason) codes are prov    5314 The Ultravisor return (reason) codes are provided by the kernel if a
5315 Ultravisor call has been executed to achieve     5315 Ultravisor call has been executed to achieve the results expected by
5316 the command. Therefore they are independent o    5316 the command. Therefore they are independent of the IOCTL return
5317 code. If KVM changes `rc`, its value will alw    5317 code. If KVM changes `rc`, its value will always be greater than 0
5318 hence setting it to 0 before issuing a PV com    5318 hence setting it to 0 before issuing a PV command is advised to be
5319 able to detect a change of `rc`.                 5319 able to detect a change of `rc`.
5320                                                  5320 
5321 **cmd values:**                                  5321 **cmd values:**
5322                                                  5322 
5323 KVM_PV_ENABLE                                    5323 KVM_PV_ENABLE
5324   Allocate memory and register the VM with th    5324   Allocate memory and register the VM with the Ultravisor, thereby
5325   donating memory to the Ultravisor that will    5325   donating memory to the Ultravisor that will become inaccessible to
5326   KVM. All existing CPUs are converted to pro    5326   KVM. All existing CPUs are converted to protected ones. After this
5327   command has succeeded, any CPU added via ho    5327   command has succeeded, any CPU added via hotplug will become
5328   protected during its creation as well.         5328   protected during its creation as well.
5329                                                  5329 
5330   Errors:                                        5330   Errors:
5331                                                  5331 
5332   =====      =============================       5332   =====      =============================
5333   EINTR      an unmasked signal is pending       5333   EINTR      an unmasked signal is pending
5334   =====      =============================       5334   =====      =============================
5335                                                  5335 
5336 KVM_PV_DISABLE                                   5336 KVM_PV_DISABLE
5337   Deregister the VM from the Ultravisor and r    5337   Deregister the VM from the Ultravisor and reclaim the memory that had
5338   been donated to the Ultravisor, making it u    5338   been donated to the Ultravisor, making it usable by the kernel again.
5339   All registered VCPUs are converted back to     5339   All registered VCPUs are converted back to non-protected ones. If a
5340   previous protected VM had been prepared for    5340   previous protected VM had been prepared for asynchronous teardown with
5341   KVM_PV_ASYNC_CLEANUP_PREPARE and not subseq    5341   KVM_PV_ASYNC_CLEANUP_PREPARE and not subsequently torn down with
5342   KVM_PV_ASYNC_CLEANUP_PERFORM, it will be to    5342   KVM_PV_ASYNC_CLEANUP_PERFORM, it will be torn down in this call
5343   together with the current protected VM.        5343   together with the current protected VM.
5344                                                  5344 
5345 KVM_PV_VM_SET_SEC_PARMS                          5345 KVM_PV_VM_SET_SEC_PARMS
5346   Pass the image header from VM memory to the    5346   Pass the image header from VM memory to the Ultravisor in
5347   preparation of image unpacking and verifica    5347   preparation of image unpacking and verification.
5348                                                  5348 
5349 KVM_PV_VM_UNPACK                                 5349 KVM_PV_VM_UNPACK
5350   Unpack (protect and decrypt) a page of the     5350   Unpack (protect and decrypt) a page of the encrypted boot image.
5351                                                  5351 
5352 KVM_PV_VM_VERIFY                                 5352 KVM_PV_VM_VERIFY
5353   Verify the integrity of the unpacked image.    5353   Verify the integrity of the unpacked image. Only if this succeeds,
5354   KVM is allowed to start protected VCPUs.       5354   KVM is allowed to start protected VCPUs.
5355                                                  5355 
5356 KVM_PV_INFO                                      5356 KVM_PV_INFO
5357   :Capability: KVM_CAP_S390_PROTECTED_DUMP       5357   :Capability: KVM_CAP_S390_PROTECTED_DUMP
5358                                                  5358 
5359   Presents an API that provides Ultravisor re    5359   Presents an API that provides Ultravisor related data to userspace
5360   via subcommands. len_max is the size of the    5360   via subcommands. len_max is the size of the user space buffer,
5361   len_written is KVM's indication of how much    5361   len_written is KVM's indication of how much bytes of that buffer
5362   were actually written to. len_written can b    5362   were actually written to. len_written can be used to determine the
5363   valid fields if more response fields are ad    5363   valid fields if more response fields are added in the future.
5364                                                  5364 
5365   ::                                             5365   ::
5366                                                  5366 
5367      enum pv_cmd_info_id {                       5367      enum pv_cmd_info_id {
5368         KVM_PV_INFO_VM,                          5368         KVM_PV_INFO_VM,
5369         KVM_PV_INFO_DUMP,                        5369         KVM_PV_INFO_DUMP,
5370      };                                          5370      };
5371                                                  5371 
5372      struct kvm_s390_pv_info_header {            5372      struct kvm_s390_pv_info_header {
5373         __u32 id;                                5373         __u32 id;
5374         __u32 len_max;                           5374         __u32 len_max;
5375         __u32 len_written;                       5375         __u32 len_written;
5376         __u32 reserved;                          5376         __u32 reserved;
5377      };                                          5377      };
5378                                                  5378 
5379      struct kvm_s390_pv_info {                   5379      struct kvm_s390_pv_info {
5380         struct kvm_s390_pv_info_header header    5380         struct kvm_s390_pv_info_header header;
5381         struct kvm_s390_pv_info_dump dump;       5381         struct kvm_s390_pv_info_dump dump;
5382         struct kvm_s390_pv_info_vm vm;           5382         struct kvm_s390_pv_info_vm vm;
5383      };                                          5383      };
5384                                                  5384 
5385 **subcommands:**                                 5385 **subcommands:**
5386                                                  5386 
5387   KVM_PV_INFO_VM                                 5387   KVM_PV_INFO_VM
5388     This subcommand provides basic Ultravisor    5388     This subcommand provides basic Ultravisor information for PV
5389     hosts. These values are likely also expor    5389     hosts. These values are likely also exported as files in the sysfs
5390     firmware UV query interface but they are     5390     firmware UV query interface but they are more easily available to
5391     programs in this API.                        5391     programs in this API.
5392                                                  5392 
5393     The installed calls and feature_indicatio    5393     The installed calls and feature_indication members provide the
5394     installed UV calls and the UV's other fea    5394     installed UV calls and the UV's other feature indications.
5395                                                  5395 
5396     The max_* members provide information abo    5396     The max_* members provide information about the maximum number of PV
5397     vcpus, PV guests and PV guest memory size    5397     vcpus, PV guests and PV guest memory size.
5398                                                  5398 
5399     ::                                           5399     ::
5400                                                  5400 
5401       struct kvm_s390_pv_info_vm {               5401       struct kvm_s390_pv_info_vm {
5402         __u64 inst_calls_list[4];                5402         __u64 inst_calls_list[4];
5403         __u64 max_cpus;                          5403         __u64 max_cpus;
5404         __u64 max_guests;                        5404         __u64 max_guests;
5405         __u64 max_guest_addr;                    5405         __u64 max_guest_addr;
5406         __u64 feature_indication;                5406         __u64 feature_indication;
5407       };                                         5407       };
5408                                                  5408 
5409                                                  5409 
5410   KVM_PV_INFO_DUMP                               5410   KVM_PV_INFO_DUMP
5411     This subcommand provides information rela    5411     This subcommand provides information related to dumping PV guests.
5412                                                  5412 
5413     ::                                           5413     ::
5414                                                  5414 
5415       struct kvm_s390_pv_info_dump {             5415       struct kvm_s390_pv_info_dump {
5416         __u64 dump_cpu_buffer_len;               5416         __u64 dump_cpu_buffer_len;
5417         __u64 dump_config_mem_buffer_per_1m;     5417         __u64 dump_config_mem_buffer_per_1m;
5418         __u64 dump_config_finalize_len;          5418         __u64 dump_config_finalize_len;
5419       };                                         5419       };
5420                                                  5420 
5421 KVM_PV_DUMP                                      5421 KVM_PV_DUMP
5422   :Capability: KVM_CAP_S390_PROTECTED_DUMP       5422   :Capability: KVM_CAP_S390_PROTECTED_DUMP
5423                                                  5423 
5424   Presents an API that provides calls which f    5424   Presents an API that provides calls which facilitate dumping a
5425   protected VM.                                  5425   protected VM.
5426                                                  5426 
5427   ::                                             5427   ::
5428                                                  5428 
5429     struct kvm_s390_pv_dmp {                     5429     struct kvm_s390_pv_dmp {
5430       __u64 subcmd;                              5430       __u64 subcmd;
5431       __u64 buff_addr;                           5431       __u64 buff_addr;
5432       __u64 buff_len;                            5432       __u64 buff_len;
5433       __u64 gaddr;              /* For dump s    5433       __u64 gaddr;              /* For dump storage state */
5434     };                                           5434     };
5435                                                  5435 
5436   **subcommands:**                               5436   **subcommands:**
5437                                                  5437 
5438   KVM_PV_DUMP_INIT                               5438   KVM_PV_DUMP_INIT
5439     Initializes the dump process of a protect    5439     Initializes the dump process of a protected VM. If this call does
5440     not succeed all other subcommands will fa    5440     not succeed all other subcommands will fail with -EINVAL. This
5441     subcommand will return -EINVAL if a dump     5441     subcommand will return -EINVAL if a dump process has not yet been
5442     completed.                                   5442     completed.
5443                                                  5443 
5444     Not all PV vms can be dumped, the owner n    5444     Not all PV vms can be dumped, the owner needs to set `dump
5445     allowed` PCF bit 34 in the SE header to a    5445     allowed` PCF bit 34 in the SE header to allow dumping.
5446                                                  5446 
5447   KVM_PV_DUMP_CONFIG_STOR_STATE                  5447   KVM_PV_DUMP_CONFIG_STOR_STATE
5448      Stores `buff_len` bytes of tweak compone    5448      Stores `buff_len` bytes of tweak component values starting with
5449      the 1MB block specified by the absolute     5449      the 1MB block specified by the absolute guest address
5450      (`gaddr`). `buff_len` needs to be `conf_    5450      (`gaddr`). `buff_len` needs to be `conf_dump_storage_state_len`
5451      aligned and at least >= the `conf_dump_s    5451      aligned and at least >= the `conf_dump_storage_state_len` value
5452      provided by the dump uv_info data. buff_    5452      provided by the dump uv_info data. buff_user might be written to
5453      even if an error rc is returned. For ins    5453      even if an error rc is returned. For instance if we encounter a
5454      fault after writing the first page of da    5454      fault after writing the first page of data.
5455                                                  5455 
5456   KVM_PV_DUMP_COMPLETE                           5456   KVM_PV_DUMP_COMPLETE
5457     If the subcommand succeeds it completes t    5457     If the subcommand succeeds it completes the dump process and lets
5458     KVM_PV_DUMP_INIT be called again.            5458     KVM_PV_DUMP_INIT be called again.
5459                                                  5459 
5460     On success `conf_dump_finalize_len` bytes    5460     On success `conf_dump_finalize_len` bytes of completion data will be
5461     stored to the `buff_addr`. The completion    5461     stored to the `buff_addr`. The completion data contains a key
5462     derivation seed, IV, tweak nonce and encr    5462     derivation seed, IV, tweak nonce and encryption keys as well as an
5463     authentication tag all of which are neede    5463     authentication tag all of which are needed to decrypt the dump at a
5464     later time.                                  5464     later time.
5465                                                  5465 
5466 KVM_PV_ASYNC_CLEANUP_PREPARE                     5466 KVM_PV_ASYNC_CLEANUP_PREPARE
5467   :Capability: KVM_CAP_S390_PROTECTED_ASYNC_D    5467   :Capability: KVM_CAP_S390_PROTECTED_ASYNC_DISABLE
5468                                                  5468 
5469   Prepare the current protected VM for asynch    5469   Prepare the current protected VM for asynchronous teardown. Most
5470   resources used by the current protected VM     5470   resources used by the current protected VM will be set aside for a
5471   subsequent asynchronous teardown. The curre    5471   subsequent asynchronous teardown. The current protected VM will then
5472   resume execution immediately as non-protect    5472   resume execution immediately as non-protected. There can be at most
5473   one protected VM prepared for asynchronous     5473   one protected VM prepared for asynchronous teardown at any time. If
5474   a protected VM had already been prepared fo    5474   a protected VM had already been prepared for teardown without
5475   subsequently calling KVM_PV_ASYNC_CLEANUP_P    5475   subsequently calling KVM_PV_ASYNC_CLEANUP_PERFORM, this call will
5476   fail. In that case, the userspace process s    5476   fail. In that case, the userspace process should issue a normal
5477   KVM_PV_DISABLE. The resources set aside wit    5477   KVM_PV_DISABLE. The resources set aside with this call will need to
5478   be cleaned up with a subsequent call to KVM    5478   be cleaned up with a subsequent call to KVM_PV_ASYNC_CLEANUP_PERFORM
5479   or KVM_PV_DISABLE, otherwise they will be c    5479   or KVM_PV_DISABLE, otherwise they will be cleaned up when KVM
5480   terminates. KVM_PV_ASYNC_CLEANUP_PREPARE ca    5480   terminates. KVM_PV_ASYNC_CLEANUP_PREPARE can be called again as soon
5481   as cleanup starts, i.e. before KVM_PV_ASYNC    5481   as cleanup starts, i.e. before KVM_PV_ASYNC_CLEANUP_PERFORM finishes.
5482                                                  5482 
5483 KVM_PV_ASYNC_CLEANUP_PERFORM                     5483 KVM_PV_ASYNC_CLEANUP_PERFORM
5484   :Capability: KVM_CAP_S390_PROTECTED_ASYNC_D    5484   :Capability: KVM_CAP_S390_PROTECTED_ASYNC_DISABLE
5485                                                  5485 
5486   Tear down the protected VM previously prepa    5486   Tear down the protected VM previously prepared for teardown with
5487   KVM_PV_ASYNC_CLEANUP_PREPARE. The resources    5487   KVM_PV_ASYNC_CLEANUP_PREPARE. The resources that had been set aside
5488   will be freed during the execution of this     5488   will be freed during the execution of this command. This PV command
5489   should ideally be issued by userspace from     5489   should ideally be issued by userspace from a separate thread. If a
5490   fatal signal is received (or the process te    5490   fatal signal is received (or the process terminates naturally), the
5491   command will terminate immediately without     5491   command will terminate immediately without completing, and the normal
5492   KVM shutdown procedure will take care of cl    5492   KVM shutdown procedure will take care of cleaning up all remaining
5493   protected VMs, including the ones whose tea    5493   protected VMs, including the ones whose teardown was interrupted by
5494   process termination.                           5494   process termination.
5495                                                  5495 
5496 4.126 KVM_XEN_HVM_SET_ATTR                       5496 4.126 KVM_XEN_HVM_SET_ATTR
5497 --------------------------                       5497 --------------------------
5498                                                  5498 
5499 :Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CO    5499 :Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CONFIG_SHARED_INFO
5500 :Architectures: x86                              5500 :Architectures: x86
5501 :Type: vm ioctl                                  5501 :Type: vm ioctl
5502 :Parameters: struct kvm_xen_hvm_attr             5502 :Parameters: struct kvm_xen_hvm_attr
5503 :Returns: 0 on success, < 0 on error             5503 :Returns: 0 on success, < 0 on error
5504                                                  5504 
5505 ::                                               5505 ::
5506                                                  5506 
5507   struct kvm_xen_hvm_attr {                      5507   struct kvm_xen_hvm_attr {
5508         __u16 type;                              5508         __u16 type;
5509         __u16 pad[3];                            5509         __u16 pad[3];
5510         union {                                  5510         union {
5511                 __u8 long_mode;                  5511                 __u8 long_mode;
5512                 __u8 vector;                     5512                 __u8 vector;
5513                 __u8 runstate_update_flag;       5513                 __u8 runstate_update_flag;
5514                 union {                          5514                 union {
5515                         __u64 gfn;               5515                         __u64 gfn;
5516                         __u64 hva;               5516                         __u64 hva;
5517                 } shared_info;                   5517                 } shared_info;
5518                 struct {                         5518                 struct {
5519                         __u32 send_port;         5519                         __u32 send_port;
5520                         __u32 type; /* EVTCHN    5520                         __u32 type; /* EVTCHNSTAT_ipi / EVTCHNSTAT_interdomain */
5521                         __u32 flags;             5521                         __u32 flags;
5522                         union {                  5522                         union {
5523                                 struct {         5523                                 struct {
5524                                         __u32    5524                                         __u32 port;
5525                                         __u32    5525                                         __u32 vcpu;
5526                                         __u32    5526                                         __u32 priority;
5527                                 } port;          5527                                 } port;
5528                                 struct {         5528                                 struct {
5529                                         __u32    5529                                         __u32 port; /* Zero for eventfd */
5530                                         __s32    5530                                         __s32 fd;
5531                                 } eventfd;       5531                                 } eventfd;
5532                                 __u32 padding    5532                                 __u32 padding[4];
5533                         } deliver;               5533                         } deliver;
5534                 } evtchn;                        5534                 } evtchn;
5535                 __u32 xen_version;               5535                 __u32 xen_version;
5536                 __u64 pad[8];                    5536                 __u64 pad[8];
5537         } u;                                     5537         } u;
5538   };                                             5538   };
5539                                                  5539 
5540 type values:                                     5540 type values:
5541                                                  5541 
5542 KVM_XEN_ATTR_TYPE_LONG_MODE                      5542 KVM_XEN_ATTR_TYPE_LONG_MODE
5543   Sets the ABI mode of the VM to 32-bit or 64    5543   Sets the ABI mode of the VM to 32-bit or 64-bit (long mode). This
5544   determines the layout of the shared_info pa    5544   determines the layout of the shared_info page exposed to the VM.
5545                                                  5545 
5546 KVM_XEN_ATTR_TYPE_SHARED_INFO                    5546 KVM_XEN_ATTR_TYPE_SHARED_INFO
5547   Sets the guest physical frame number at whi    5547   Sets the guest physical frame number at which the Xen shared_info
5548   page resides. Note that although Xen places    5548   page resides. Note that although Xen places vcpu_info for the first
5549   32 vCPUs in the shared_info page, KVM does     5549   32 vCPUs in the shared_info page, KVM does not automatically do so
5550   and instead requires that KVM_XEN_VCPU_ATTR    5550   and instead requires that KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO or
5551   KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO_HVA be use    5551   KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO_HVA be used explicitly even when
5552   the vcpu_info for a given vCPU resides at t    5552   the vcpu_info for a given vCPU resides at the "default" location
5553   in the shared_info page. This is because KV    5553   in the shared_info page. This is because KVM may not be aware of
5554   the Xen CPU id which is used as the index i    5554   the Xen CPU id which is used as the index into the vcpu_info[]
5555   array, so may know the correct default loca    5555   array, so may know the correct default location.
5556                                                  5556 
5557   Note that the shared_info page may be const    5557   Note that the shared_info page may be constantly written to by KVM;
5558   it contains the event channel bitmap used t    5558   it contains the event channel bitmap used to deliver interrupts to
5559   a Xen guest, amongst other things. It is ex    5559   a Xen guest, amongst other things. It is exempt from dirty tracking
5560   mechanisms — KVM will not explicitly mark    5560   mechanisms — KVM will not explicitly mark the page as dirty each
5561   time an event channel interrupt is delivere    5561   time an event channel interrupt is delivered to the guest! Thus,
5562   userspace should always assume that the des    5562   userspace should always assume that the designated GFN is dirty if
5563   any vCPU has been running or any event chan    5563   any vCPU has been running or any event channel interrupts can be
5564   routed to the guest.                           5564   routed to the guest.
5565                                                  5565 
5566   Setting the gfn to KVM_XEN_INVALID_GFN will    5566   Setting the gfn to KVM_XEN_INVALID_GFN will disable the shared_info
5567   page.                                          5567   page.
5568                                                  5568 
5569 KVM_XEN_ATTR_TYPE_SHARED_INFO_HVA                5569 KVM_XEN_ATTR_TYPE_SHARED_INFO_HVA
5570   If the KVM_XEN_HVM_CONFIG_SHARED_INFO_HVA f    5570   If the KVM_XEN_HVM_CONFIG_SHARED_INFO_HVA flag is also set in the
5571   Xen capabilities, then this attribute may b    5571   Xen capabilities, then this attribute may be used to set the
5572   userspace address at which the shared_info     5572   userspace address at which the shared_info page resides, which
5573   will always be fixed in the VMM regardless     5573   will always be fixed in the VMM regardless of where it is mapped
5574   in guest physical address space. This attri    5574   in guest physical address space. This attribute should be used in
5575   preference to KVM_XEN_ATTR_TYPE_SHARED_INFO    5575   preference to KVM_XEN_ATTR_TYPE_SHARED_INFO as it avoids
5576   unnecessary invalidation of an internal cac    5576   unnecessary invalidation of an internal cache when the page is
5577   re-mapped in guest physcial address space.     5577   re-mapped in guest physcial address space.
5578                                                  5578 
5579   Setting the hva to zero will disable the sh    5579   Setting the hva to zero will disable the shared_info page.
5580                                                  5580 
5581 KVM_XEN_ATTR_TYPE_UPCALL_VECTOR                  5581 KVM_XEN_ATTR_TYPE_UPCALL_VECTOR
5582   Sets the exception vector used to deliver X    5582   Sets the exception vector used to deliver Xen event channel upcalls.
5583   This is the HVM-wide vector injected direct    5583   This is the HVM-wide vector injected directly by the hypervisor
5584   (not through the local APIC), typically con    5584   (not through the local APIC), typically configured by a guest via
5585   HVM_PARAM_CALLBACK_IRQ. This can be disable    5585   HVM_PARAM_CALLBACK_IRQ. This can be disabled again (e.g. for guest
5586   SHUTDOWN_soft_reset) by setting it to zero.    5586   SHUTDOWN_soft_reset) by setting it to zero.
5587                                                  5587 
5588 KVM_XEN_ATTR_TYPE_EVTCHN                         5588 KVM_XEN_ATTR_TYPE_EVTCHN
5589   This attribute is available when the KVM_CA    5589   This attribute is available when the KVM_CAP_XEN_HVM ioctl indicates
5590   support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND     5590   support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND features. It configures
5591   an outbound port number for interception of    5591   an outbound port number for interception of EVTCHNOP_send requests
5592   from the guest. A given sending port number    5592   from the guest. A given sending port number may be directed back to
5593   a specified vCPU (by APIC ID) / port / prio    5593   a specified vCPU (by APIC ID) / port / priority on the guest, or to
5594   trigger events on an eventfd. The vCPU and     5594   trigger events on an eventfd. The vCPU and priority can be changed
5595   by setting KVM_XEN_EVTCHN_UPDATE in a subse    5595   by setting KVM_XEN_EVTCHN_UPDATE in a subsequent call, but other
5596   fields cannot change for a given sending po    5596   fields cannot change for a given sending port. A port mapping is
5597   removed by using KVM_XEN_EVTCHN_DEASSIGN in    5597   removed by using KVM_XEN_EVTCHN_DEASSIGN in the flags field. Passing
5598   KVM_XEN_EVTCHN_RESET in the flags field rem    5598   KVM_XEN_EVTCHN_RESET in the flags field removes all interception of
5599   outbound event channels. The values of the     5599   outbound event channels. The values of the flags field are mutually
5600   exclusive and cannot be combined as a bitma    5600   exclusive and cannot be combined as a bitmask.
5601                                                  5601 
5602 KVM_XEN_ATTR_TYPE_XEN_VERSION                    5602 KVM_XEN_ATTR_TYPE_XEN_VERSION
5603   This attribute is available when the KVM_CA    5603   This attribute is available when the KVM_CAP_XEN_HVM ioctl indicates
5604   support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND     5604   support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND features. It configures
5605   the 32-bit version code returned to the gue    5605   the 32-bit version code returned to the guest when it invokes the
5606   XENVER_version call; typically (XEN_MAJOR <    5606   XENVER_version call; typically (XEN_MAJOR << 16 | XEN_MINOR). PV
5607   Xen guests will often use this to as a dumm    5607   Xen guests will often use this to as a dummy hypercall to trigger
5608   event channel delivery, so responding withi    5608   event channel delivery, so responding within the kernel without
5609   exiting to userspace is beneficial.            5609   exiting to userspace is beneficial.
5610                                                  5610 
5611 KVM_XEN_ATTR_TYPE_RUNSTATE_UPDATE_FLAG           5611 KVM_XEN_ATTR_TYPE_RUNSTATE_UPDATE_FLAG
5612   This attribute is available when the KVM_CA    5612   This attribute is available when the KVM_CAP_XEN_HVM ioctl indicates
5613   support for KVM_XEN_HVM_CONFIG_RUNSTATE_UPD    5613   support for KVM_XEN_HVM_CONFIG_RUNSTATE_UPDATE_FLAG. It enables the
5614   XEN_RUNSTATE_UPDATE flag which allows guest    5614   XEN_RUNSTATE_UPDATE flag which allows guest vCPUs to safely read
5615   other vCPUs' vcpu_runstate_info. Xen guests    5615   other vCPUs' vcpu_runstate_info. Xen guests enable this feature via
5616   the VMASST_TYPE_runstate_update_flag of the    5616   the VMASST_TYPE_runstate_update_flag of the HYPERVISOR_vm_assist
5617   hypercall.                                     5617   hypercall.
5618                                                  5618 
5619 4.127 KVM_XEN_HVM_GET_ATTR                       5619 4.127 KVM_XEN_HVM_GET_ATTR
5620 --------------------------                       5620 --------------------------
5621                                                  5621 
5622 :Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CO    5622 :Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CONFIG_SHARED_INFO
5623 :Architectures: x86                              5623 :Architectures: x86
5624 :Type: vm ioctl                                  5624 :Type: vm ioctl
5625 :Parameters: struct kvm_xen_hvm_attr             5625 :Parameters: struct kvm_xen_hvm_attr
5626 :Returns: 0 on success, < 0 on error             5626 :Returns: 0 on success, < 0 on error
5627                                                  5627 
5628 Allows Xen VM attributes to be read. For the     5628 Allows Xen VM attributes to be read. For the structure and types,
5629 see KVM_XEN_HVM_SET_ATTR above. The KVM_XEN_A    5629 see KVM_XEN_HVM_SET_ATTR above. The KVM_XEN_ATTR_TYPE_EVTCHN
5630 attribute cannot be read.                        5630 attribute cannot be read.
5631                                                  5631 
5632 4.128 KVM_XEN_VCPU_SET_ATTR                      5632 4.128 KVM_XEN_VCPU_SET_ATTR
5633 ---------------------------                      5633 ---------------------------
5634                                                  5634 
5635 :Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CO    5635 :Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CONFIG_SHARED_INFO
5636 :Architectures: x86                              5636 :Architectures: x86
5637 :Type: vcpu ioctl                                5637 :Type: vcpu ioctl
5638 :Parameters: struct kvm_xen_vcpu_attr            5638 :Parameters: struct kvm_xen_vcpu_attr
5639 :Returns: 0 on success, < 0 on error             5639 :Returns: 0 on success, < 0 on error
5640                                                  5640 
5641 ::                                               5641 ::
5642                                                  5642 
5643   struct kvm_xen_vcpu_attr {                     5643   struct kvm_xen_vcpu_attr {
5644         __u16 type;                              5644         __u16 type;
5645         __u16 pad[3];                            5645         __u16 pad[3];
5646         union {                                  5646         union {
5647                 __u64 gpa;                       5647                 __u64 gpa;
5648                 __u64 pad[4];                    5648                 __u64 pad[4];
5649                 struct {                         5649                 struct {
5650                         __u64 state;             5650                         __u64 state;
5651                         __u64 state_entry_tim    5651                         __u64 state_entry_time;
5652                         __u64 time_running;      5652                         __u64 time_running;
5653                         __u64 time_runnable;     5653                         __u64 time_runnable;
5654                         __u64 time_blocked;      5654                         __u64 time_blocked;
5655                         __u64 time_offline;      5655                         __u64 time_offline;
5656                 } runstate;                      5656                 } runstate;
5657                 __u32 vcpu_id;                   5657                 __u32 vcpu_id;
5658                 struct {                         5658                 struct {
5659                         __u32 port;              5659                         __u32 port;
5660                         __u32 priority;          5660                         __u32 priority;
5661                         __u64 expires_ns;        5661                         __u64 expires_ns;
5662                 } timer;                         5662                 } timer;
5663                 __u8 vector;                     5663                 __u8 vector;
5664         } u;                                     5664         } u;
5665   };                                             5665   };
5666                                                  5666 
5667 type values:                                     5667 type values:
5668                                                  5668 
5669 KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO                 5669 KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO
5670   Sets the guest physical address of the vcpu    5670   Sets the guest physical address of the vcpu_info for a given vCPU.
5671   As with the shared_info page for the VM, th    5671   As with the shared_info page for the VM, the corresponding page may be
5672   dirtied at any time if event channel interr    5672   dirtied at any time if event channel interrupt delivery is enabled, so
5673   userspace should always assume that the pag    5673   userspace should always assume that the page is dirty without relying
5674   on dirty logging. Setting the gpa to KVM_XE    5674   on dirty logging. Setting the gpa to KVM_XEN_INVALID_GPA will disable
5675   the vcpu_info.                                 5675   the vcpu_info.
5676                                                  5676 
5677 KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO_HVA             5677 KVM_XEN_VCPU_ATTR_TYPE_VCPU_INFO_HVA
5678   If the KVM_XEN_HVM_CONFIG_SHARED_INFO_HVA f    5678   If the KVM_XEN_HVM_CONFIG_SHARED_INFO_HVA flag is also set in the
5679   Xen capabilities, then this attribute may b    5679   Xen capabilities, then this attribute may be used to set the
5680   userspace address of the vcpu_info for a gi    5680   userspace address of the vcpu_info for a given vCPU. It should
5681   only be used when the vcpu_info resides at     5681   only be used when the vcpu_info resides at the "default" location
5682   in the shared_info page. In this case it is    5682   in the shared_info page. In this case it is safe to assume the
5683   userspace address will not change, because     5683   userspace address will not change, because the shared_info page is
5684   an overlay on guest memory and remains at a    5684   an overlay on guest memory and remains at a fixed host address
5685   regardless of where it is mapped in guest p    5685   regardless of where it is mapped in guest physical address space
5686   and hence unnecessary invalidation of an in    5686   and hence unnecessary invalidation of an internal cache may be
5687   avoided if the guest memory layout is modif    5687   avoided if the guest memory layout is modified.
5688   If the vcpu_info does not reside at the "de    5688   If the vcpu_info does not reside at the "default" location then
5689   it is not guaranteed to remain at the same     5689   it is not guaranteed to remain at the same host address and
5690   hence the aforementioned cache invalidation    5690   hence the aforementioned cache invalidation is required.
5691                                                  5691 
5692 KVM_XEN_VCPU_ATTR_TYPE_VCPU_TIME_INFO            5692 KVM_XEN_VCPU_ATTR_TYPE_VCPU_TIME_INFO
5693   Sets the guest physical address of an addit    5693   Sets the guest physical address of an additional pvclock structure
5694   for a given vCPU. This is typically used fo    5694   for a given vCPU. This is typically used for guest vsyscall support.
5695   Setting the gpa to KVM_XEN_INVALID_GPA will    5695   Setting the gpa to KVM_XEN_INVALID_GPA will disable the structure.
5696                                                  5696 
5697 KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADDR             5697 KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADDR
5698   Sets the guest physical address of the vcpu    5698   Sets the guest physical address of the vcpu_runstate_info for a given
5699   vCPU. This is how a Xen guest tracks CPU st    5699   vCPU. This is how a Xen guest tracks CPU state such as steal time.
5700   Setting the gpa to KVM_XEN_INVALID_GPA will    5700   Setting the gpa to KVM_XEN_INVALID_GPA will disable the runstate area.
5701                                                  5701 
5702 KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_CURRENT          5702 KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_CURRENT
5703   Sets the runstate (RUNSTATE_running/_runnab    5703   Sets the runstate (RUNSTATE_running/_runnable/_blocked/_offline) of
5704   the given vCPU from the .u.runstate.state m    5704   the given vCPU from the .u.runstate.state member of the structure.
5705   KVM automatically accounts running and runn    5705   KVM automatically accounts running and runnable time but blocked
5706   and offline states are only entered explici    5706   and offline states are only entered explicitly.
5707                                                  5707 
5708 KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_DATA             5708 KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_DATA
5709   Sets all fields of the vCPU runstate data f    5709   Sets all fields of the vCPU runstate data from the .u.runstate member
5710   of the structure, including the current run    5710   of the structure, including the current runstate. The state_entry_time
5711   must equal the sum of the other four times.    5711   must equal the sum of the other four times.
5712                                                  5712 
5713 KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADJUST           5713 KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADJUST
5714   This *adds* the contents of the .u.runstate    5714   This *adds* the contents of the .u.runstate members of the structure
5715   to the corresponding members of the given v    5715   to the corresponding members of the given vCPU's runstate data, thus
5716   permitting atomic adjustments to the runsta    5716   permitting atomic adjustments to the runstate times. The adjustment
5717   to the state_entry_time must equal the sum     5717   to the state_entry_time must equal the sum of the adjustments to the
5718   other four times. The state field must be s    5718   other four times. The state field must be set to -1, or to a valid
5719   runstate value (RUNSTATE_running, RUNSTATE_    5719   runstate value (RUNSTATE_running, RUNSTATE_runnable, RUNSTATE_blocked
5720   or RUNSTATE_offline) to set the current acc    5720   or RUNSTATE_offline) to set the current accounted state as of the
5721   adjusted state_entry_time.                     5721   adjusted state_entry_time.
5722                                                  5722 
5723 KVM_XEN_VCPU_ATTR_TYPE_VCPU_ID                   5723 KVM_XEN_VCPU_ATTR_TYPE_VCPU_ID
5724   This attribute is available when the KVM_CA    5724   This attribute is available when the KVM_CAP_XEN_HVM ioctl indicates
5725   support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND     5725   support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND features. It sets the Xen
5726   vCPU ID of the given vCPU, to allow timer-r    5726   vCPU ID of the given vCPU, to allow timer-related VCPU operations to
5727   be intercepted by KVM.                         5727   be intercepted by KVM.
5728                                                  5728 
5729 KVM_XEN_VCPU_ATTR_TYPE_TIMER                     5729 KVM_XEN_VCPU_ATTR_TYPE_TIMER
5730   This attribute is available when the KVM_CA    5730   This attribute is available when the KVM_CAP_XEN_HVM ioctl indicates
5731   support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND     5731   support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND features. It sets the
5732   event channel port/priority for the VIRQ_TI    5732   event channel port/priority for the VIRQ_TIMER of the vCPU, as well
5733   as allowing a pending timer to be saved/res    5733   as allowing a pending timer to be saved/restored. Setting the timer
5734   port to zero disables kernel handling of th    5734   port to zero disables kernel handling of the singleshot timer.
5735                                                  5735 
5736 KVM_XEN_VCPU_ATTR_TYPE_UPCALL_VECTOR             5736 KVM_XEN_VCPU_ATTR_TYPE_UPCALL_VECTOR
5737   This attribute is available when the KVM_CA    5737   This attribute is available when the KVM_CAP_XEN_HVM ioctl indicates
5738   support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND     5738   support for KVM_XEN_HVM_CONFIG_EVTCHN_SEND features. It sets the
5739   per-vCPU local APIC upcall vector, configur    5739   per-vCPU local APIC upcall vector, configured by a Xen guest with
5740   the HVMOP_set_evtchn_upcall_vector hypercal    5740   the HVMOP_set_evtchn_upcall_vector hypercall. This is typically
5741   used by Windows guests, and is distinct fro    5741   used by Windows guests, and is distinct from the HVM-wide upcall
5742   vector configured with HVM_PARAM_CALLBACK_I    5742   vector configured with HVM_PARAM_CALLBACK_IRQ. It is disabled by
5743   setting the vector to zero.                    5743   setting the vector to zero.
5744                                                  5744 
5745                                                  5745 
5746 4.129 KVM_XEN_VCPU_GET_ATTR                      5746 4.129 KVM_XEN_VCPU_GET_ATTR
5747 ---------------------------                      5747 ---------------------------
5748                                                  5748 
5749 :Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CO    5749 :Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CONFIG_SHARED_INFO
5750 :Architectures: x86                              5750 :Architectures: x86
5751 :Type: vcpu ioctl                                5751 :Type: vcpu ioctl
5752 :Parameters: struct kvm_xen_vcpu_attr            5752 :Parameters: struct kvm_xen_vcpu_attr
5753 :Returns: 0 on success, < 0 on error             5753 :Returns: 0 on success, < 0 on error
5754                                                  5754 
5755 Allows Xen vCPU attributes to be read. For th    5755 Allows Xen vCPU attributes to be read. For the structure and types,
5756 see KVM_XEN_VCPU_SET_ATTR above.                 5756 see KVM_XEN_VCPU_SET_ATTR above.
5757                                                  5757 
5758 The KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADJUST ty    5758 The KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADJUST type may not be used
5759 with the KVM_XEN_VCPU_GET_ATTR ioctl.            5759 with the KVM_XEN_VCPU_GET_ATTR ioctl.
5760                                                  5760 
5761 4.130 KVM_ARM_MTE_COPY_TAGS                      5761 4.130 KVM_ARM_MTE_COPY_TAGS
5762 ---------------------------                      5762 ---------------------------
5763                                                  5763 
5764 :Capability: KVM_CAP_ARM_MTE                     5764 :Capability: KVM_CAP_ARM_MTE
5765 :Architectures: arm64                            5765 :Architectures: arm64
5766 :Type: vm ioctl                                  5766 :Type: vm ioctl
5767 :Parameters: struct kvm_arm_copy_mte_tags        5767 :Parameters: struct kvm_arm_copy_mte_tags
5768 :Returns: number of bytes copied, < 0 on erro    5768 :Returns: number of bytes copied, < 0 on error (-EINVAL for incorrect
5769           arguments, -EFAULT if memory cannot    5769           arguments, -EFAULT if memory cannot be accessed).
5770                                                  5770 
5771 ::                                               5771 ::
5772                                                  5772 
5773   struct kvm_arm_copy_mte_tags {                 5773   struct kvm_arm_copy_mte_tags {
5774         __u64 guest_ipa;                         5774         __u64 guest_ipa;
5775         __u64 length;                            5775         __u64 length;
5776         void __user *addr;                       5776         void __user *addr;
5777         __u64 flags;                             5777         __u64 flags;
5778         __u64 reserved[2];                       5778         __u64 reserved[2];
5779   };                                             5779   };
5780                                                  5780 
5781 Copies Memory Tagging Extension (MTE) tags to    5781 Copies Memory Tagging Extension (MTE) tags to/from guest tag memory. The
5782 ``guest_ipa`` and ``length`` fields must be `    5782 ``guest_ipa`` and ``length`` fields must be ``PAGE_SIZE`` aligned.
5783 ``length`` must not be bigger than 2^31 - PAG    5783 ``length`` must not be bigger than 2^31 - PAGE_SIZE bytes. The ``addr``
5784 field must point to a buffer which the tags w    5784 field must point to a buffer which the tags will be copied to or from.
5785                                                  5785 
5786 ``flags`` specifies the direction of copy, ei    5786 ``flags`` specifies the direction of copy, either ``KVM_ARM_TAGS_TO_GUEST`` or
5787 ``KVM_ARM_TAGS_FROM_GUEST``.                     5787 ``KVM_ARM_TAGS_FROM_GUEST``.
5788                                                  5788 
5789 The size of the buffer to store the tags is `    5789 The size of the buffer to store the tags is ``(length / 16)`` bytes
5790 (granules in MTE are 16 bytes long). Each byt    5790 (granules in MTE are 16 bytes long). Each byte contains a single tag
5791 value. This matches the format of ``PTRACE_PE    5791 value. This matches the format of ``PTRACE_PEEKMTETAGS`` and
5792 ``PTRACE_POKEMTETAGS``.                          5792 ``PTRACE_POKEMTETAGS``.
5793                                                  5793 
5794 If an error occurs before any data is copied     5794 If an error occurs before any data is copied then a negative error code is
5795 returned. If some tags have been copied befor    5795 returned. If some tags have been copied before an error occurs then the number
5796 of bytes successfully copied is returned. If     5796 of bytes successfully copied is returned. If the call completes successfully
5797 then ``length`` is returned.                     5797 then ``length`` is returned.
5798                                                  5798 
5799 4.131 KVM_GET_SREGS2                             5799 4.131 KVM_GET_SREGS2
5800 --------------------                             5800 --------------------
5801                                                  5801 
5802 :Capability: KVM_CAP_SREGS2                      5802 :Capability: KVM_CAP_SREGS2
5803 :Architectures: x86                              5803 :Architectures: x86
5804 :Type: vcpu ioctl                                5804 :Type: vcpu ioctl
5805 :Parameters: struct kvm_sregs2 (out)             5805 :Parameters: struct kvm_sregs2 (out)
5806 :Returns: 0 on success, -1 on error              5806 :Returns: 0 on success, -1 on error
5807                                                  5807 
5808 Reads special registers from the vcpu.           5808 Reads special registers from the vcpu.
5809 This ioctl (when supported) replaces the KVM_    5809 This ioctl (when supported) replaces the KVM_GET_SREGS.
5810                                                  5810 
5811 ::                                               5811 ::
5812                                                  5812 
5813         struct kvm_sregs2 {                      5813         struct kvm_sregs2 {
5814                 /* out (KVM_GET_SREGS2) / in     5814                 /* out (KVM_GET_SREGS2) / in (KVM_SET_SREGS2) */
5815                 struct kvm_segment cs, ds, es    5815                 struct kvm_segment cs, ds, es, fs, gs, ss;
5816                 struct kvm_segment tr, ldt;      5816                 struct kvm_segment tr, ldt;
5817                 struct kvm_dtable gdt, idt;      5817                 struct kvm_dtable gdt, idt;
5818                 __u64 cr0, cr2, cr3, cr4, cr8    5818                 __u64 cr0, cr2, cr3, cr4, cr8;
5819                 __u64 efer;                      5819                 __u64 efer;
5820                 __u64 apic_base;                 5820                 __u64 apic_base;
5821                 __u64 flags;                     5821                 __u64 flags;
5822                 __u64 pdptrs[4];                 5822                 __u64 pdptrs[4];
5823         };                                       5823         };
5824                                                  5824 
5825 flags values for ``kvm_sregs2``:                 5825 flags values for ``kvm_sregs2``:
5826                                                  5826 
5827 ``KVM_SREGS2_FLAGS_PDPTRS_VALID``                5827 ``KVM_SREGS2_FLAGS_PDPTRS_VALID``
5828                                                  5828 
5829   Indicates that the struct contains valid PD    5829   Indicates that the struct contains valid PDPTR values.
5830                                                  5830 
5831                                                  5831 
5832 4.132 KVM_SET_SREGS2                             5832 4.132 KVM_SET_SREGS2
5833 --------------------                             5833 --------------------
5834                                                  5834 
5835 :Capability: KVM_CAP_SREGS2                      5835 :Capability: KVM_CAP_SREGS2
5836 :Architectures: x86                              5836 :Architectures: x86
5837 :Type: vcpu ioctl                                5837 :Type: vcpu ioctl
5838 :Parameters: struct kvm_sregs2 (in)              5838 :Parameters: struct kvm_sregs2 (in)
5839 :Returns: 0 on success, -1 on error              5839 :Returns: 0 on success, -1 on error
5840                                                  5840 
5841 Writes special registers into the vcpu.          5841 Writes special registers into the vcpu.
5842 See KVM_GET_SREGS2 for the data structures.      5842 See KVM_GET_SREGS2 for the data structures.
5843 This ioctl (when supported) replaces the KVM_    5843 This ioctl (when supported) replaces the KVM_SET_SREGS.
5844                                                  5844 
5845 4.133 KVM_GET_STATS_FD                           5845 4.133 KVM_GET_STATS_FD
5846 ----------------------                           5846 ----------------------
5847                                                  5847 
5848 :Capability: KVM_CAP_STATS_BINARY_FD             5848 :Capability: KVM_CAP_STATS_BINARY_FD
5849 :Architectures: all                              5849 :Architectures: all
5850 :Type: vm ioctl, vcpu ioctl                      5850 :Type: vm ioctl, vcpu ioctl
5851 :Parameters: none                                5851 :Parameters: none
5852 :Returns: statistics file descriptor on succe    5852 :Returns: statistics file descriptor on success, < 0 on error
5853                                                  5853 
5854 Errors:                                          5854 Errors:
5855                                                  5855 
5856   ======     ================================    5856   ======     ======================================================
5857   ENOMEM     if the fd could not be created d    5857   ENOMEM     if the fd could not be created due to lack of memory
5858   EMFILE     if the number of opened files ex    5858   EMFILE     if the number of opened files exceeds the limit
5859   ======     ================================    5859   ======     ======================================================
5860                                                  5860 
5861 The returned file descriptor can be used to r    5861 The returned file descriptor can be used to read VM/vCPU statistics data in
5862 binary format. The data in the file descripto    5862 binary format. The data in the file descriptor consists of four blocks
5863 organized as follows:                            5863 organized as follows:
5864                                                  5864 
5865 +-------------+                                  5865 +-------------+
5866 |   Header    |                                  5866 |   Header    |
5867 +-------------+                                  5867 +-------------+
5868 |  id string  |                                  5868 |  id string  |
5869 +-------------+                                  5869 +-------------+
5870 | Descriptors |                                  5870 | Descriptors |
5871 +-------------+                                  5871 +-------------+
5872 | Stats Data  |                                  5872 | Stats Data  |
5873 +-------------+                                  5873 +-------------+
5874                                                  5874 
5875 Apart from the header starting at offset 0, p    5875 Apart from the header starting at offset 0, please be aware that it is
5876 not guaranteed that the four blocks are adjac    5876 not guaranteed that the four blocks are adjacent or in the above order;
5877 the offsets of the id, descriptors and data b    5877 the offsets of the id, descriptors and data blocks are found in the
5878 header.  However, all four blocks are aligned    5878 header.  However, all four blocks are aligned to 64 bit offsets in the
5879 file and they do not overlap.                    5879 file and they do not overlap.
5880                                                  5880 
5881 All blocks except the data block are immutabl    5881 All blocks except the data block are immutable.  Userspace can read them
5882 only one time after retrieving the file descr    5882 only one time after retrieving the file descriptor, and then use ``pread`` or
5883 ``lseek`` to read the statistics repeatedly.     5883 ``lseek`` to read the statistics repeatedly.
5884                                                  5884 
5885 All data is in system endianness.                5885 All data is in system endianness.
5886                                                  5886 
5887 The format of the header is as follows::         5887 The format of the header is as follows::
5888                                                  5888 
5889         struct kvm_stats_header {                5889         struct kvm_stats_header {
5890                 __u32 flags;                     5890                 __u32 flags;
5891                 __u32 name_size;                 5891                 __u32 name_size;
5892                 __u32 num_desc;                  5892                 __u32 num_desc;
5893                 __u32 id_offset;                 5893                 __u32 id_offset;
5894                 __u32 desc_offset;               5894                 __u32 desc_offset;
5895                 __u32 data_offset;               5895                 __u32 data_offset;
5896         };                                       5896         };
5897                                                  5897 
5898 The ``flags`` field is not used at the moment    5898 The ``flags`` field is not used at the moment. It is always read as 0.
5899                                                  5899 
5900 The ``name_size`` field is the size (in byte)    5900 The ``name_size`` field is the size (in byte) of the statistics name string
5901 (including trailing '\0') which is contained     5901 (including trailing '\0') which is contained in the "id string" block and
5902 appended at the end of every descriptor.         5902 appended at the end of every descriptor.
5903                                                  5903 
5904 The ``num_desc`` field is the number of descr    5904 The ``num_desc`` field is the number of descriptors that are included in the
5905 descriptor block.  (The actual number of valu    5905 descriptor block.  (The actual number of values in the data block may be
5906 larger, since each descriptor may comprise mo    5906 larger, since each descriptor may comprise more than one value).
5907                                                  5907 
5908 The ``id_offset`` field is the offset of the     5908 The ``id_offset`` field is the offset of the id string from the start of the
5909 file indicated by the file descriptor. It is     5909 file indicated by the file descriptor. It is a multiple of 8.
5910                                                  5910 
5911 The ``desc_offset`` field is the offset of th    5911 The ``desc_offset`` field is the offset of the Descriptors block from the start
5912 of the file indicated by the file descriptor.    5912 of the file indicated by the file descriptor. It is a multiple of 8.
5913                                                  5913 
5914 The ``data_offset`` field is the offset of th    5914 The ``data_offset`` field is the offset of the Stats Data block from the start
5915 of the file indicated by the file descriptor.    5915 of the file indicated by the file descriptor. It is a multiple of 8.
5916                                                  5916 
5917 The id string block contains a string which i    5917 The id string block contains a string which identifies the file descriptor on
5918 which KVM_GET_STATS_FD was invoked.  The size    5918 which KVM_GET_STATS_FD was invoked.  The size of the block, including the
5919 trailing ``'\0'``, is indicated by the ``name    5919 trailing ``'\0'``, is indicated by the ``name_size`` field in the header.
5920                                                  5920 
5921 The descriptors block is only needed to be re    5921 The descriptors block is only needed to be read once for the lifetime of the
5922 file descriptor contains a sequence of ``stru    5922 file descriptor contains a sequence of ``struct kvm_stats_desc``, each followed
5923 by a string of size ``name_size``.               5923 by a string of size ``name_size``.
5924 ::                                               5924 ::
5925                                                  5925 
5926         #define KVM_STATS_TYPE_SHIFT             5926         #define KVM_STATS_TYPE_SHIFT            0
5927         #define KVM_STATS_TYPE_MASK              5927         #define KVM_STATS_TYPE_MASK             (0xF << KVM_STATS_TYPE_SHIFT)
5928         #define KVM_STATS_TYPE_CUMULATIVE        5928         #define KVM_STATS_TYPE_CUMULATIVE       (0x0 << KVM_STATS_TYPE_SHIFT)
5929         #define KVM_STATS_TYPE_INSTANT           5929         #define KVM_STATS_TYPE_INSTANT          (0x1 << KVM_STATS_TYPE_SHIFT)
5930         #define KVM_STATS_TYPE_PEAK              5930         #define KVM_STATS_TYPE_PEAK             (0x2 << KVM_STATS_TYPE_SHIFT)
5931         #define KVM_STATS_TYPE_LINEAR_HIST       5931         #define KVM_STATS_TYPE_LINEAR_HIST      (0x3 << KVM_STATS_TYPE_SHIFT)
5932         #define KVM_STATS_TYPE_LOG_HIST          5932         #define KVM_STATS_TYPE_LOG_HIST         (0x4 << KVM_STATS_TYPE_SHIFT)
5933         #define KVM_STATS_TYPE_MAX               5933         #define KVM_STATS_TYPE_MAX              KVM_STATS_TYPE_LOG_HIST
5934                                                  5934 
5935         #define KVM_STATS_UNIT_SHIFT             5935         #define KVM_STATS_UNIT_SHIFT            4
5936         #define KVM_STATS_UNIT_MASK              5936         #define KVM_STATS_UNIT_MASK             (0xF << KVM_STATS_UNIT_SHIFT)
5937         #define KVM_STATS_UNIT_NONE              5937         #define KVM_STATS_UNIT_NONE             (0x0 << KVM_STATS_UNIT_SHIFT)
5938         #define KVM_STATS_UNIT_BYTES             5938         #define KVM_STATS_UNIT_BYTES            (0x1 << KVM_STATS_UNIT_SHIFT)
5939         #define KVM_STATS_UNIT_SECONDS           5939         #define KVM_STATS_UNIT_SECONDS          (0x2 << KVM_STATS_UNIT_SHIFT)
5940         #define KVM_STATS_UNIT_CYCLES            5940         #define KVM_STATS_UNIT_CYCLES           (0x3 << KVM_STATS_UNIT_SHIFT)
5941         #define KVM_STATS_UNIT_BOOLEAN           5941         #define KVM_STATS_UNIT_BOOLEAN          (0x4 << KVM_STATS_UNIT_SHIFT)
5942         #define KVM_STATS_UNIT_MAX               5942         #define KVM_STATS_UNIT_MAX              KVM_STATS_UNIT_BOOLEAN
5943                                                  5943 
5944         #define KVM_STATS_BASE_SHIFT             5944         #define KVM_STATS_BASE_SHIFT            8
5945         #define KVM_STATS_BASE_MASK              5945         #define KVM_STATS_BASE_MASK             (0xF << KVM_STATS_BASE_SHIFT)
5946         #define KVM_STATS_BASE_POW10             5946         #define KVM_STATS_BASE_POW10            (0x0 << KVM_STATS_BASE_SHIFT)
5947         #define KVM_STATS_BASE_POW2              5947         #define KVM_STATS_BASE_POW2             (0x1 << KVM_STATS_BASE_SHIFT)
5948         #define KVM_STATS_BASE_MAX               5948         #define KVM_STATS_BASE_MAX              KVM_STATS_BASE_POW2
5949                                                  5949 
5950         struct kvm_stats_desc {                  5950         struct kvm_stats_desc {
5951                 __u32 flags;                     5951                 __u32 flags;
5952                 __s16 exponent;                  5952                 __s16 exponent;
5953                 __u16 size;                      5953                 __u16 size;
5954                 __u32 offset;                    5954                 __u32 offset;
5955                 __u32 bucket_size;               5955                 __u32 bucket_size;
5956                 char name[];                     5956                 char name[];
5957         };                                       5957         };
5958                                                  5958 
5959 The ``flags`` field contains the type and uni    5959 The ``flags`` field contains the type and unit of the statistics data described
5960 by this descriptor. Its endianness is CPU nat    5960 by this descriptor. Its endianness is CPU native.
5961 The following flags are supported:               5961 The following flags are supported:
5962                                                  5962 
5963 Bits 0-3 of ``flags`` encode the type:           5963 Bits 0-3 of ``flags`` encode the type:
5964                                                  5964 
5965   * ``KVM_STATS_TYPE_CUMULATIVE``                5965   * ``KVM_STATS_TYPE_CUMULATIVE``
5966     The statistics reports a cumulative count    5966     The statistics reports a cumulative count. The value of data can only be increased.
5967     Most of the counters used in KVM are of t    5967     Most of the counters used in KVM are of this type.
5968     The corresponding ``size`` field for this    5968     The corresponding ``size`` field for this type is always 1.
5969     All cumulative statistics data are read/w    5969     All cumulative statistics data are read/write.
5970   * ``KVM_STATS_TYPE_INSTANT``                   5970   * ``KVM_STATS_TYPE_INSTANT``
5971     The statistics reports an instantaneous v    5971     The statistics reports an instantaneous value. Its value can be increased or
5972     decreased. This type is usually used as a    5972     decreased. This type is usually used as a measurement of some resources,
5973     like the number of dirty pages, the numbe    5973     like the number of dirty pages, the number of large pages, etc.
5974     All instant statistics are read only.        5974     All instant statistics are read only.
5975     The corresponding ``size`` field for this    5975     The corresponding ``size`` field for this type is always 1.
5976   * ``KVM_STATS_TYPE_PEAK``                      5976   * ``KVM_STATS_TYPE_PEAK``
5977     The statistics data reports a peak value,    5977     The statistics data reports a peak value, for example the maximum number
5978     of items in a hash table bucket, the long    5978     of items in a hash table bucket, the longest time waited and so on.
5979     The value of data can only be increased.     5979     The value of data can only be increased.
5980     The corresponding ``size`` field for this    5980     The corresponding ``size`` field for this type is always 1.
5981   * ``KVM_STATS_TYPE_LINEAR_HIST``               5981   * ``KVM_STATS_TYPE_LINEAR_HIST``
5982     The statistic is reported as a linear his    5982     The statistic is reported as a linear histogram. The number of
5983     buckets is specified by the ``size`` fiel    5983     buckets is specified by the ``size`` field. The size of buckets is specified
5984     by the ``hist_param`` field. The range of    5984     by the ``hist_param`` field. The range of the Nth bucket (1 <= N < ``size``)
5985     is [``hist_param``*(N-1), ``hist_param``*    5985     is [``hist_param``*(N-1), ``hist_param``*N), while the range of the last
5986     bucket is [``hist_param``*(``size``-1), +    5986     bucket is [``hist_param``*(``size``-1), +INF). (+INF means positive infinity
5987     value.)                                      5987     value.)
5988   * ``KVM_STATS_TYPE_LOG_HIST``                  5988   * ``KVM_STATS_TYPE_LOG_HIST``
5989     The statistic is reported as a logarithmi    5989     The statistic is reported as a logarithmic histogram. The number of
5990     buckets is specified by the ``size`` fiel    5990     buckets is specified by the ``size`` field. The range of the first bucket is
5991     [0, 1), while the range of the last bucke    5991     [0, 1), while the range of the last bucket is [pow(2, ``size``-2), +INF).
5992     Otherwise, The Nth bucket (1 < N < ``size    5992     Otherwise, The Nth bucket (1 < N < ``size``) covers
5993     [pow(2, N-2), pow(2, N-1)).                  5993     [pow(2, N-2), pow(2, N-1)).
5994                                                  5994 
5995 Bits 4-7 of ``flags`` encode the unit:           5995 Bits 4-7 of ``flags`` encode the unit:
5996                                                  5996 
5997   * ``KVM_STATS_UNIT_NONE``                      5997   * ``KVM_STATS_UNIT_NONE``
5998     There is no unit for the value of statist    5998     There is no unit for the value of statistics data. This usually means that
5999     the value is a simple counter of an event    5999     the value is a simple counter of an event.
6000   * ``KVM_STATS_UNIT_BYTES``                     6000   * ``KVM_STATS_UNIT_BYTES``
6001     It indicates that the statistics data is     6001     It indicates that the statistics data is used to measure memory size, in the
6002     unit of Byte, KiByte, MiByte, GiByte, etc    6002     unit of Byte, KiByte, MiByte, GiByte, etc. The unit of the data is
6003     determined by the ``exponent`` field in t    6003     determined by the ``exponent`` field in the descriptor.
6004   * ``KVM_STATS_UNIT_SECONDS``                   6004   * ``KVM_STATS_UNIT_SECONDS``
6005     It indicates that the statistics data is     6005     It indicates that the statistics data is used to measure time or latency.
6006   * ``KVM_STATS_UNIT_CYCLES``                    6006   * ``KVM_STATS_UNIT_CYCLES``
6007     It indicates that the statistics data is     6007     It indicates that the statistics data is used to measure CPU clock cycles.
6008   * ``KVM_STATS_UNIT_BOOLEAN``                   6008   * ``KVM_STATS_UNIT_BOOLEAN``
6009     It indicates that the statistic will alwa    6009     It indicates that the statistic will always be either 0 or 1.  Boolean
6010     statistics of "peak" type will never go b    6010     statistics of "peak" type will never go back from 1 to 0.  Boolean
6011     statistics can be linear histograms (with    6011     statistics can be linear histograms (with two buckets) but not logarithmic
6012     histograms.                                  6012     histograms.
6013                                                  6013 
6014 Note that, in the case of histograms, the uni    6014 Note that, in the case of histograms, the unit applies to the bucket
6015 ranges, while the bucket value indicates how     6015 ranges, while the bucket value indicates how many samples fell in the
6016 bucket's range.                                  6016 bucket's range.
6017                                                  6017 
6018 Bits 8-11 of ``flags``, together with ``expon    6018 Bits 8-11 of ``flags``, together with ``exponent``, encode the scale of the
6019 unit:                                            6019 unit:
6020                                                  6020 
6021   * ``KVM_STATS_BASE_POW10``                     6021   * ``KVM_STATS_BASE_POW10``
6022     The scale is based on power of 10. It is     6022     The scale is based on power of 10. It is used for measurement of time and
6023     CPU clock cycles.  For example, an expone    6023     CPU clock cycles.  For example, an exponent of -9 can be used with
6024     ``KVM_STATS_UNIT_SECONDS`` to express tha    6024     ``KVM_STATS_UNIT_SECONDS`` to express that the unit is nanoseconds.
6025   * ``KVM_STATS_BASE_POW2``                      6025   * ``KVM_STATS_BASE_POW2``
6026     The scale is based on power of 2. It is u    6026     The scale is based on power of 2. It is used for measurement of memory size.
6027     For example, an exponent of 20 can be use    6027     For example, an exponent of 20 can be used with ``KVM_STATS_UNIT_BYTES`` to
6028     express that the unit is MiB.                6028     express that the unit is MiB.
6029                                                  6029 
6030 The ``size`` field is the number of values of    6030 The ``size`` field is the number of values of this statistics data. Its
6031 value is usually 1 for most of simple statist    6031 value is usually 1 for most of simple statistics. 1 means it contains an
6032 unsigned 64bit data.                             6032 unsigned 64bit data.
6033                                                  6033 
6034 The ``offset`` field is the offset from the s    6034 The ``offset`` field is the offset from the start of Data Block to the start of
6035 the corresponding statistics data.               6035 the corresponding statistics data.
6036                                                  6036 
6037 The ``bucket_size`` field is used as a parame    6037 The ``bucket_size`` field is used as a parameter for histogram statistics data.
6038 It is only used by linear histogram statistic    6038 It is only used by linear histogram statistics data, specifying the size of a
6039 bucket in the unit expressed by bits 4-11 of     6039 bucket in the unit expressed by bits 4-11 of ``flags`` together with ``exponent``.
6040                                                  6040 
6041 The ``name`` field is the name string of the     6041 The ``name`` field is the name string of the statistics data. The name string
6042 starts at the end of ``struct kvm_stats_desc`    6042 starts at the end of ``struct kvm_stats_desc``.  The maximum length including
6043 the trailing ``'\0'``, is indicated by ``name    6043 the trailing ``'\0'``, is indicated by ``name_size`` in the header.
6044                                                  6044 
6045 The Stats Data block contains an array of 64-    6045 The Stats Data block contains an array of 64-bit values in the same order
6046 as the descriptors in Descriptors block.         6046 as the descriptors in Descriptors block.
6047                                                  6047 
6048 4.134 KVM_GET_XSAVE2                             6048 4.134 KVM_GET_XSAVE2
6049 --------------------                             6049 --------------------
6050                                                  6050 
6051 :Capability: KVM_CAP_XSAVE2                      6051 :Capability: KVM_CAP_XSAVE2
6052 :Architectures: x86                              6052 :Architectures: x86
6053 :Type: vcpu ioctl                                6053 :Type: vcpu ioctl
6054 :Parameters: struct kvm_xsave (out)              6054 :Parameters: struct kvm_xsave (out)
6055 :Returns: 0 on success, -1 on error              6055 :Returns: 0 on success, -1 on error
6056                                                  6056 
6057                                                  6057 
6058 ::                                               6058 ::
6059                                                  6059 
6060   struct kvm_xsave {                             6060   struct kvm_xsave {
6061         __u32 region[1024];                      6061         __u32 region[1024];
6062         __u32 extra[0];                          6062         __u32 extra[0];
6063   };                                             6063   };
6064                                                  6064 
6065 This ioctl would copy current vcpu's xsave st    6065 This ioctl would copy current vcpu's xsave struct to the userspace. It
6066 copies as many bytes as are returned by KVM_C    6066 copies as many bytes as are returned by KVM_CHECK_EXTENSION(KVM_CAP_XSAVE2)
6067 when invoked on the vm file descriptor. The s    6067 when invoked on the vm file descriptor. The size value returned by
6068 KVM_CHECK_EXTENSION(KVM_CAP_XSAVE2) will alwa    6068 KVM_CHECK_EXTENSION(KVM_CAP_XSAVE2) will always be at least 4096.
6069 Currently, it is only greater than 4096 if a     6069 Currently, it is only greater than 4096 if a dynamic feature has been
6070 enabled with ``arch_prctl()``, but this may c    6070 enabled with ``arch_prctl()``, but this may change in the future.
6071                                                  6071 
6072 The offsets of the state save areas in struct    6072 The offsets of the state save areas in struct kvm_xsave follow the contents
6073 of CPUID leaf 0xD on the host.                   6073 of CPUID leaf 0xD on the host.
6074                                                  6074 
6075 4.135 KVM_XEN_HVM_EVTCHN_SEND                    6075 4.135 KVM_XEN_HVM_EVTCHN_SEND
6076 -----------------------------                    6076 -----------------------------
6077                                                  6077 
6078 :Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CO    6078 :Capability: KVM_CAP_XEN_HVM / KVM_XEN_HVM_CONFIG_EVTCHN_SEND
6079 :Architectures: x86                              6079 :Architectures: x86
6080 :Type: vm ioctl                                  6080 :Type: vm ioctl
6081 :Parameters: struct kvm_irq_routing_xen_evtch    6081 :Parameters: struct kvm_irq_routing_xen_evtchn
6082 :Returns: 0 on success, < 0 on error             6082 :Returns: 0 on success, < 0 on error
6083                                                  6083 
6084                                                  6084 
6085 ::                                               6085 ::
6086                                                  6086 
6087    struct kvm_irq_routing_xen_evtchn {           6087    struct kvm_irq_routing_xen_evtchn {
6088         __u32 port;                              6088         __u32 port;
6089         __u32 vcpu;                              6089         __u32 vcpu;
6090         __u32 priority;                          6090         __u32 priority;
6091    };                                            6091    };
6092                                                  6092 
6093 This ioctl injects an event channel interrupt    6093 This ioctl injects an event channel interrupt directly to the guest vCPU.
6094                                                  6094 
6095 4.136 KVM_S390_PV_CPU_COMMAND                    6095 4.136 KVM_S390_PV_CPU_COMMAND
6096 -----------------------------                    6096 -----------------------------
6097                                                  6097 
6098 :Capability: KVM_CAP_S390_PROTECTED_DUMP         6098 :Capability: KVM_CAP_S390_PROTECTED_DUMP
6099 :Architectures: s390                             6099 :Architectures: s390
6100 :Type: vcpu ioctl                                6100 :Type: vcpu ioctl
6101 :Parameters: none                                6101 :Parameters: none
6102 :Returns: 0 on success, < 0 on error             6102 :Returns: 0 on success, < 0 on error
6103                                                  6103 
6104 This ioctl closely mirrors `KVM_S390_PV_COMMA    6104 This ioctl closely mirrors `KVM_S390_PV_COMMAND` but handles requests
6105 for vcpus. It re-uses the kvm_s390_pv_dmp str    6105 for vcpus. It re-uses the kvm_s390_pv_dmp struct and hence also shares
6106 the command ids.                                 6106 the command ids.
6107                                                  6107 
6108 **command:**                                     6108 **command:**
6109                                                  6109 
6110 KVM_PV_DUMP                                      6110 KVM_PV_DUMP
6111   Presents an API that provides calls which f    6111   Presents an API that provides calls which facilitate dumping a vcpu
6112   of a protected VM.                             6112   of a protected VM.
6113                                                  6113 
6114 **subcommand:**                                  6114 **subcommand:**
6115                                                  6115 
6116 KVM_PV_DUMP_CPU                                  6116 KVM_PV_DUMP_CPU
6117   Provides encrypted dump data like register     6117   Provides encrypted dump data like register values.
6118   The length of the returned data is provided    6118   The length of the returned data is provided by uv_info.guest_cpu_stor_len.
6119                                                  6119 
6120 4.137 KVM_S390_ZPCI_OP                           6120 4.137 KVM_S390_ZPCI_OP
6121 ----------------------                           6121 ----------------------
6122                                                  6122 
6123 :Capability: KVM_CAP_S390_ZPCI_OP                6123 :Capability: KVM_CAP_S390_ZPCI_OP
6124 :Architectures: s390                             6124 :Architectures: s390
6125 :Type: vm ioctl                                  6125 :Type: vm ioctl
6126 :Parameters: struct kvm_s390_zpci_op (in)        6126 :Parameters: struct kvm_s390_zpci_op (in)
6127 :Returns: 0 on success, <0 on error              6127 :Returns: 0 on success, <0 on error
6128                                                  6128 
6129 Used to manage hardware-assisted virtualizati    6129 Used to manage hardware-assisted virtualization features for zPCI devices.
6130                                                  6130 
6131 Parameters are specified via the following st    6131 Parameters are specified via the following structure::
6132                                                  6132 
6133   struct kvm_s390_zpci_op {                      6133   struct kvm_s390_zpci_op {
6134         /* in */                                 6134         /* in */
6135         __u32 fh;               /* target dev    6135         __u32 fh;               /* target device */
6136         __u8  op;               /* operation     6136         __u8  op;               /* operation to perform */
6137         __u8  pad[3];                            6137         __u8  pad[3];
6138         union {                                  6138         union {
6139                 /* for KVM_S390_ZPCIOP_REG_AE    6139                 /* for KVM_S390_ZPCIOP_REG_AEN */
6140                 struct {                         6140                 struct {
6141                         __u64 ibv;      /* Gu    6141                         __u64 ibv;      /* Guest addr of interrupt bit vector */
6142                         __u64 sb;       /* Gu    6142                         __u64 sb;       /* Guest addr of summary bit */
6143                         __u32 flags;             6143                         __u32 flags;
6144                         __u32 noi;      /* Nu    6144                         __u32 noi;      /* Number of interrupts */
6145                         __u8 isc;       /* Gu    6145                         __u8 isc;       /* Guest interrupt subclass */
6146                         __u8 sbo;       /* Of    6146                         __u8 sbo;       /* Offset of guest summary bit vector */
6147                         __u16 pad;               6147                         __u16 pad;
6148                 } reg_aen;                       6148                 } reg_aen;
6149                 __u64 reserved[8];               6149                 __u64 reserved[8];
6150         } u;                                     6150         } u;
6151   };                                             6151   };
6152                                                  6152 
6153 The type of operation is specified in the "op    6153 The type of operation is specified in the "op" field.
6154 KVM_S390_ZPCIOP_REG_AEN is used to register t    6154 KVM_S390_ZPCIOP_REG_AEN is used to register the VM for adapter event
6155 notification interpretation, which will allow    6155 notification interpretation, which will allow firmware delivery of adapter
6156 events directly to the vm, with KVM providing    6156 events directly to the vm, with KVM providing a backup delivery mechanism;
6157 KVM_S390_ZPCIOP_DEREG_AEN is used to subseque    6157 KVM_S390_ZPCIOP_DEREG_AEN is used to subsequently disable interpretation of
6158 adapter event notifications.                     6158 adapter event notifications.
6159                                                  6159 
6160 The target zPCI function must also be specifi    6160 The target zPCI function must also be specified via the "fh" field.  For the
6161 KVM_S390_ZPCIOP_REG_AEN operation, additional    6161 KVM_S390_ZPCIOP_REG_AEN operation, additional information to establish firmware
6162 delivery must be provided via the "reg_aen" s    6162 delivery must be provided via the "reg_aen" struct.
6163                                                  6163 
6164 The "pad" and "reserved" fields may be used f    6164 The "pad" and "reserved" fields may be used for future extensions and should be
6165 set to 0s by userspace.                          6165 set to 0s by userspace.
6166                                                  6166 
6167 4.138 KVM_ARM_SET_COUNTER_OFFSET                 6167 4.138 KVM_ARM_SET_COUNTER_OFFSET
6168 --------------------------------                 6168 --------------------------------
6169                                                  6169 
6170 :Capability: KVM_CAP_COUNTER_OFFSET              6170 :Capability: KVM_CAP_COUNTER_OFFSET
6171 :Architectures: arm64                            6171 :Architectures: arm64
6172 :Type: vm ioctl                                  6172 :Type: vm ioctl
6173 :Parameters: struct kvm_arm_counter_offset (i    6173 :Parameters: struct kvm_arm_counter_offset (in)
6174 :Returns: 0 on success, < 0 on error             6174 :Returns: 0 on success, < 0 on error
6175                                                  6175 
6176 This capability indicates that userspace is a    6176 This capability indicates that userspace is able to apply a single VM-wide
6177 offset to both the virtual and physical count    6177 offset to both the virtual and physical counters as viewed by the guest
6178 using the KVM_ARM_SET_CNT_OFFSET ioctl and th    6178 using the KVM_ARM_SET_CNT_OFFSET ioctl and the following data structure:
6179                                                  6179 
6180 ::                                               6180 ::
6181                                                  6181 
6182         struct kvm_arm_counter_offset {          6182         struct kvm_arm_counter_offset {
6183                 __u64 counter_offset;            6183                 __u64 counter_offset;
6184                 __u64 reserved;                  6184                 __u64 reserved;
6185         };                                       6185         };
6186                                                  6186 
6187 The offset describes a number of counter cycl    6187 The offset describes a number of counter cycles that are subtracted from
6188 both virtual and physical counter views (simi    6188 both virtual and physical counter views (similar to the effects of the
6189 CNTVOFF_EL2 and CNTPOFF_EL2 system registers,    6189 CNTVOFF_EL2 and CNTPOFF_EL2 system registers, but only global). The offset
6190 always applies to all vcpus (already created     6190 always applies to all vcpus (already created or created after this ioctl)
6191 for this VM.                                     6191 for this VM.
6192                                                  6192 
6193 It is userspace's responsibility to compute t    6193 It is userspace's responsibility to compute the offset based, for example,
6194 on previous values of the guest counters.        6194 on previous values of the guest counters.
6195                                                  6195 
6196 Any value other than 0 for the "reserved" fie    6196 Any value other than 0 for the "reserved" field may result in an error
6197 (-EINVAL) being returned. This ioctl can also    6197 (-EINVAL) being returned. This ioctl can also return -EBUSY if any vcpu
6198 ioctl is issued concurrently.                    6198 ioctl is issued concurrently.
6199                                                  6199 
6200 Note that using this ioctl results in KVM ign    6200 Note that using this ioctl results in KVM ignoring subsequent userspace
6201 writes to the CNTVCT_EL0 and CNTPCT_EL0 regis    6201 writes to the CNTVCT_EL0 and CNTPCT_EL0 registers using the SET_ONE_REG
6202 interface. No error will be returned, but the    6202 interface. No error will be returned, but the resulting offset will not be
6203 applied.                                         6203 applied.
6204                                                  6204 
6205 .. _KVM_ARM_GET_REG_WRITABLE_MASKS:              6205 .. _KVM_ARM_GET_REG_WRITABLE_MASKS:
6206                                                  6206 
6207 4.139 KVM_ARM_GET_REG_WRITABLE_MASKS             6207 4.139 KVM_ARM_GET_REG_WRITABLE_MASKS
6208 -------------------------------------------      6208 -------------------------------------------
6209                                                  6209 
6210 :Capability: KVM_CAP_ARM_SUPPORTED_REG_MASK_R    6210 :Capability: KVM_CAP_ARM_SUPPORTED_REG_MASK_RANGES
6211 :Architectures: arm64                            6211 :Architectures: arm64
6212 :Type: vm ioctl                                  6212 :Type: vm ioctl
6213 :Parameters: struct reg_mask_range (in/out)      6213 :Parameters: struct reg_mask_range (in/out)
6214 :Returns: 0 on success, < 0 on error             6214 :Returns: 0 on success, < 0 on error
6215                                                  6215 
6216                                                  6216 
6217 ::                                               6217 ::
6218                                                  6218 
6219         #define KVM_ARM_FEATURE_ID_RANGE         6219         #define KVM_ARM_FEATURE_ID_RANGE        0
6220         #define KVM_ARM_FEATURE_ID_RANGE_SIZE    6220         #define KVM_ARM_FEATURE_ID_RANGE_SIZE   (3 * 8 * 8)
6221                                                  6221 
6222         struct reg_mask_range {                  6222         struct reg_mask_range {
6223                 __u64 addr;             /* Po    6223                 __u64 addr;             /* Pointer to mask array */
6224                 __u32 range;            /* Re    6224                 __u32 range;            /* Requested range */
6225                 __u32 reserved[13];              6225                 __u32 reserved[13];
6226         };                                       6226         };
6227                                                  6227 
6228 This ioctl copies the writable masks for a se    6228 This ioctl copies the writable masks for a selected range of registers to
6229 userspace.                                       6229 userspace.
6230                                                  6230 
6231 The ``addr`` field is a pointer to the destin    6231 The ``addr`` field is a pointer to the destination array where KVM copies
6232 the writable masks.                              6232 the writable masks.
6233                                                  6233 
6234 The ``range`` field indicates the requested r    6234 The ``range`` field indicates the requested range of registers.
6235 ``KVM_CHECK_EXTENSION`` for the ``KVM_CAP_ARM    6235 ``KVM_CHECK_EXTENSION`` for the ``KVM_CAP_ARM_SUPPORTED_REG_MASK_RANGES``
6236 capability returns the supported ranges, expr    6236 capability returns the supported ranges, expressed as a set of flags. Each
6237 flag's bit index represents a possible value     6237 flag's bit index represents a possible value for the ``range`` field.
6238 All other values are reserved for future use     6238 All other values are reserved for future use and KVM may return an error.
6239                                                  6239 
6240 The ``reserved[13]`` array is reserved for fu    6240 The ``reserved[13]`` array is reserved for future use and should be 0, or
6241 KVM may return an error.                         6241 KVM may return an error.
6242                                                  6242 
6243 KVM_ARM_FEATURE_ID_RANGE (0)                     6243 KVM_ARM_FEATURE_ID_RANGE (0)
6244 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^                     6244 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
6245                                                  6245 
6246 The Feature ID range is defined as the AArch6    6246 The Feature ID range is defined as the AArch64 System register space with
6247 op0==3, op1=={0, 1, 3}, CRn==0, CRm=={0-7}, o    6247 op0==3, op1=={0, 1, 3}, CRn==0, CRm=={0-7}, op2=={0-7}.
6248                                                  6248 
6249 The mask returned array pointed to by ``addr`    6249 The mask returned array pointed to by ``addr`` is indexed by the macro
6250 ``ARM64_FEATURE_ID_RANGE_IDX(op0, op1, crn, c    6250 ``ARM64_FEATURE_ID_RANGE_IDX(op0, op1, crn, crm, op2)``, allowing userspace
6251 to know what fields can be changed for the sy    6251 to know what fields can be changed for the system register described by
6252 ``op0, op1, crn, crm, op2``. KVM rejects ID r    6252 ``op0, op1, crn, crm, op2``. KVM rejects ID register values that describe a
6253 superset of the features supported by the sys    6253 superset of the features supported by the system.
6254                                                  6254 
6255 4.140 KVM_SET_USER_MEMORY_REGION2                6255 4.140 KVM_SET_USER_MEMORY_REGION2
6256 ---------------------------------                6256 ---------------------------------
6257                                                  6257 
6258 :Capability: KVM_CAP_USER_MEMORY2                6258 :Capability: KVM_CAP_USER_MEMORY2
6259 :Architectures: all                              6259 :Architectures: all
6260 :Type: vm ioctl                                  6260 :Type: vm ioctl
6261 :Parameters: struct kvm_userspace_memory_regi    6261 :Parameters: struct kvm_userspace_memory_region2 (in)
6262 :Returns: 0 on success, -1 on error              6262 :Returns: 0 on success, -1 on error
6263                                                  6263 
6264 KVM_SET_USER_MEMORY_REGION2 is an extension t    6264 KVM_SET_USER_MEMORY_REGION2 is an extension to KVM_SET_USER_MEMORY_REGION that
6265 allows mapping guest_memfd memory into a gues    6265 allows mapping guest_memfd memory into a guest.  All fields shared with
6266 KVM_SET_USER_MEMORY_REGION identically.  User    6266 KVM_SET_USER_MEMORY_REGION identically.  Userspace can set KVM_MEM_GUEST_MEMFD
6267 in flags to have KVM bind the memory region t    6267 in flags to have KVM bind the memory region to a given guest_memfd range of
6268 [guest_memfd_offset, guest_memfd_offset + mem    6268 [guest_memfd_offset, guest_memfd_offset + memory_size].  The target guest_memfd
6269 must point at a file created via KVM_CREATE_G    6269 must point at a file created via KVM_CREATE_GUEST_MEMFD on the current VM, and
6270 the target range must not be bound to any oth    6270 the target range must not be bound to any other memory region.  All standard
6271 bounds checks apply (use common sense).          6271 bounds checks apply (use common sense).
6272                                                  6272 
6273 ::                                               6273 ::
6274                                                  6274 
6275   struct kvm_userspace_memory_region2 {          6275   struct kvm_userspace_memory_region2 {
6276         __u32 slot;                              6276         __u32 slot;
6277         __u32 flags;                             6277         __u32 flags;
6278         __u64 guest_phys_addr;                   6278         __u64 guest_phys_addr;
6279         __u64 memory_size; /* bytes */           6279         __u64 memory_size; /* bytes */
6280         __u64 userspace_addr; /* start of the    6280         __u64 userspace_addr; /* start of the userspace allocated memory */
6281         __u64 guest_memfd_offset;                6281         __u64 guest_memfd_offset;
6282         __u32 guest_memfd;                       6282         __u32 guest_memfd;
6283         __u32 pad1;                              6283         __u32 pad1;
6284         __u64 pad2[14];                          6284         __u64 pad2[14];
6285   };                                             6285   };
6286                                                  6286 
6287 A KVM_MEM_GUEST_MEMFD region _must_ have a va    6287 A KVM_MEM_GUEST_MEMFD region _must_ have a valid guest_memfd (private memory) and
6288 userspace_addr (shared memory).  However, "va    6288 userspace_addr (shared memory).  However, "valid" for userspace_addr simply
6289 means that the address itself must be a legal    6289 means that the address itself must be a legal userspace address.  The backing
6290 mapping for userspace_addr is not required to    6290 mapping for userspace_addr is not required to be valid/populated at the time of
6291 KVM_SET_USER_MEMORY_REGION2, e.g. shared memo    6291 KVM_SET_USER_MEMORY_REGION2, e.g. shared memory can be lazily mapped/allocated
6292 on-demand.                                       6292 on-demand.
6293                                                  6293 
6294 When mapping a gfn into the guest, KVM select    6294 When mapping a gfn into the guest, KVM selects shared vs. private, i.e consumes
6295 userspace_addr vs. guest_memfd, based on the     6295 userspace_addr vs. guest_memfd, based on the gfn's KVM_MEMORY_ATTRIBUTE_PRIVATE
6296 state.  At VM creation time, all memory is sh    6296 state.  At VM creation time, all memory is shared, i.e. the PRIVATE attribute
6297 is '0' for all gfns.  Userspace can control w    6297 is '0' for all gfns.  Userspace can control whether memory is shared/private by
6298 toggling KVM_MEMORY_ATTRIBUTE_PRIVATE via KVM    6298 toggling KVM_MEMORY_ATTRIBUTE_PRIVATE via KVM_SET_MEMORY_ATTRIBUTES as needed.
6299                                                  6299 
6300 S390:                                            6300 S390:
6301 ^^^^^                                            6301 ^^^^^
6302                                                  6302 
6303 Returns -EINVAL if the VM has the KVM_VM_S390    6303 Returns -EINVAL if the VM has the KVM_VM_S390_UCONTROL flag set.
6304 Returns -EINVAL if called on a protected VM.     6304 Returns -EINVAL if called on a protected VM.
6305                                                  6305 
6306 4.141 KVM_SET_MEMORY_ATTRIBUTES                  6306 4.141 KVM_SET_MEMORY_ATTRIBUTES
6307 -------------------------------                  6307 -------------------------------
6308                                                  6308 
6309 :Capability: KVM_CAP_MEMORY_ATTRIBUTES           6309 :Capability: KVM_CAP_MEMORY_ATTRIBUTES
6310 :Architectures: x86                              6310 :Architectures: x86
6311 :Type: vm ioctl                                  6311 :Type: vm ioctl
6312 :Parameters: struct kvm_memory_attributes (in    6312 :Parameters: struct kvm_memory_attributes (in)
6313 :Returns: 0 on success, <0 on error              6313 :Returns: 0 on success, <0 on error
6314                                                  6314 
6315 KVM_SET_MEMORY_ATTRIBUTES allows userspace to    6315 KVM_SET_MEMORY_ATTRIBUTES allows userspace to set memory attributes for a range
6316 of guest physical memory.                        6316 of guest physical memory.
6317                                                  6317 
6318 ::                                               6318 ::
6319                                                  6319 
6320   struct kvm_memory_attributes {                 6320   struct kvm_memory_attributes {
6321         __u64 address;                           6321         __u64 address;
6322         __u64 size;                              6322         __u64 size;
6323         __u64 attributes;                        6323         __u64 attributes;
6324         __u64 flags;                             6324         __u64 flags;
6325   };                                             6325   };
6326                                                  6326 
6327   #define KVM_MEMORY_ATTRIBUTE_PRIVATE           6327   #define KVM_MEMORY_ATTRIBUTE_PRIVATE           (1ULL << 3)
6328                                                  6328 
6329 The address and size must be page aligned.  T    6329 The address and size must be page aligned.  The supported attributes can be
6330 retrieved via ioctl(KVM_CHECK_EXTENSION) on K    6330 retrieved via ioctl(KVM_CHECK_EXTENSION) on KVM_CAP_MEMORY_ATTRIBUTES.  If
6331 executed on a VM, KVM_CAP_MEMORY_ATTRIBUTES p    6331 executed on a VM, KVM_CAP_MEMORY_ATTRIBUTES precisely returns the attributes
6332 supported by that VM.  If executed at system     6332 supported by that VM.  If executed at system scope, KVM_CAP_MEMORY_ATTRIBUTES
6333 returns all attributes supported by KVM.  The    6333 returns all attributes supported by KVM.  The only attribute defined at this
6334 time is KVM_MEMORY_ATTRIBUTE_PRIVATE, which m    6334 time is KVM_MEMORY_ATTRIBUTE_PRIVATE, which marks the associated gfn as being
6335 guest private memory.                            6335 guest private memory.
6336                                                  6336 
6337 Note, there is no "get" API.  Userspace is re    6337 Note, there is no "get" API.  Userspace is responsible for explicitly tracking
6338 the state of a gfn/page as needed.               6338 the state of a gfn/page as needed.
6339                                                  6339 
6340 The "flags" field is reserved for future exte    6340 The "flags" field is reserved for future extensions and must be '0'.
6341                                                  6341 
6342 4.142 KVM_CREATE_GUEST_MEMFD                     6342 4.142 KVM_CREATE_GUEST_MEMFD
6343 ----------------------------                     6343 ----------------------------
6344                                                  6344 
6345 :Capability: KVM_CAP_GUEST_MEMFD                 6345 :Capability: KVM_CAP_GUEST_MEMFD
6346 :Architectures: none                             6346 :Architectures: none
6347 :Type: vm ioctl                                  6347 :Type: vm ioctl
6348 :Parameters: struct kvm_create_guest_memfd(in    6348 :Parameters: struct kvm_create_guest_memfd(in)
6349 :Returns: A file descriptor on success, <0 on    6349 :Returns: A file descriptor on success, <0 on error
6350                                                  6350 
6351 KVM_CREATE_GUEST_MEMFD creates an anonymous f    6351 KVM_CREATE_GUEST_MEMFD creates an anonymous file and returns a file descriptor
6352 that refers to it.  guest_memfd files are rou    6352 that refers to it.  guest_memfd files are roughly analogous to files created
6353 via memfd_create(), e.g. guest_memfd files li    6353 via memfd_create(), e.g. guest_memfd files live in RAM, have volatile storage,
6354 and are automatically released when the last     6354 and are automatically released when the last reference is dropped.  Unlike
6355 "regular" memfd_create() files, guest_memfd f    6355 "regular" memfd_create() files, guest_memfd files are bound to their owning
6356 virtual machine (see below), cannot be mapped    6356 virtual machine (see below), cannot be mapped, read, or written by userspace,
6357 and cannot be resized  (guest_memfd files do     6357 and cannot be resized  (guest_memfd files do however support PUNCH_HOLE).
6358                                                  6358 
6359 ::                                               6359 ::
6360                                                  6360 
6361   struct kvm_create_guest_memfd {                6361   struct kvm_create_guest_memfd {
6362         __u64 size;                              6362         __u64 size;
6363         __u64 flags;                             6363         __u64 flags;
6364         __u64 reserved[6];                       6364         __u64 reserved[6];
6365   };                                             6365   };
6366                                                  6366 
6367 Conceptually, the inode backing a guest_memfd    6367 Conceptually, the inode backing a guest_memfd file represents physical memory,
6368 i.e. is coupled to the virtual machine as a t    6368 i.e. is coupled to the virtual machine as a thing, not to a "struct kvm".  The
6369 file itself, which is bound to a "struct kvm"    6369 file itself, which is bound to a "struct kvm", is that instance's view of the
6370 underlying memory, e.g. effectively provides     6370 underlying memory, e.g. effectively provides the translation of guest addresses
6371 to host memory.  This allows for use cases wh    6371 to host memory.  This allows for use cases where multiple KVM structures are
6372 used to manage a single virtual machine, e.g.    6372 used to manage a single virtual machine, e.g. when performing intrahost
6373 migration of a virtual machine.                  6373 migration of a virtual machine.
6374                                                  6374 
6375 KVM currently only supports mapping guest_mem    6375 KVM currently only supports mapping guest_memfd via KVM_SET_USER_MEMORY_REGION2,
6376 and more specifically via the guest_memfd and    6376 and more specifically via the guest_memfd and guest_memfd_offset fields in
6377 "struct kvm_userspace_memory_region2", where     6377 "struct kvm_userspace_memory_region2", where guest_memfd_offset is the offset
6378 into the guest_memfd instance.  For a given g    6378 into the guest_memfd instance.  For a given guest_memfd file, there can be at
6379 most one mapping per page, i.e. binding multi    6379 most one mapping per page, i.e. binding multiple memory regions to a single
6380 guest_memfd range is not allowed (any number     6380 guest_memfd range is not allowed (any number of memory regions can be bound to
6381 a single guest_memfd file, but the bound rang    6381 a single guest_memfd file, but the bound ranges must not overlap).
6382                                                  6382 
6383 See KVM_SET_USER_MEMORY_REGION2 for additiona    6383 See KVM_SET_USER_MEMORY_REGION2 for additional details.
6384                                                  6384 
6385 4.143 KVM_PRE_FAULT_MEMORY                       6385 4.143 KVM_PRE_FAULT_MEMORY
6386 ---------------------------                      6386 ---------------------------
6387                                                  6387 
6388 :Capability: KVM_CAP_PRE_FAULT_MEMORY            6388 :Capability: KVM_CAP_PRE_FAULT_MEMORY
6389 :Architectures: none                             6389 :Architectures: none
6390 :Type: vcpu ioctl                                6390 :Type: vcpu ioctl
6391 :Parameters: struct kvm_pre_fault_memory (in/    6391 :Parameters: struct kvm_pre_fault_memory (in/out)
6392 :Returns: 0 if at least one page is processed    6392 :Returns: 0 if at least one page is processed, < 0 on error
6393                                                  6393 
6394 Errors:                                          6394 Errors:
6395                                                  6395 
6396   ========== ================================    6396   ========== ===============================================================
6397   EINVAL     The specified `gpa` and `size` w    6397   EINVAL     The specified `gpa` and `size` were invalid (e.g. not
6398              page aligned, causes an overflow    6398              page aligned, causes an overflow, or size is zero).
6399   ENOENT     The specified `gpa` is outside d    6399   ENOENT     The specified `gpa` is outside defined memslots.
6400   EINTR      An unmasked signal is pending an    6400   EINTR      An unmasked signal is pending and no page was processed.
6401   EFAULT     The parameter address was invali    6401   EFAULT     The parameter address was invalid.
6402   EOPNOTSUPP Mapping memory for a GPA is unsu    6402   EOPNOTSUPP Mapping memory for a GPA is unsupported by the
6403              hypervisor, and/or for the curre    6403              hypervisor, and/or for the current vCPU state/mode.
6404   EIO        unexpected error conditions (als    6404   EIO        unexpected error conditions (also causes a WARN)
6405   ========== ================================    6405   ========== ===============================================================
6406                                                  6406 
6407 ::                                               6407 ::
6408                                                  6408 
6409   struct kvm_pre_fault_memory {                  6409   struct kvm_pre_fault_memory {
6410         /* in/out */                             6410         /* in/out */
6411         __u64 gpa;                               6411         __u64 gpa;
6412         __u64 size;                              6412         __u64 size;
6413         /* in */                                 6413         /* in */
6414         __u64 flags;                             6414         __u64 flags;
6415         __u64 padding[5];                        6415         __u64 padding[5];
6416   };                                             6416   };
6417                                                  6417 
6418 KVM_PRE_FAULT_MEMORY populates KVM's stage-2     6418 KVM_PRE_FAULT_MEMORY populates KVM's stage-2 page tables used to map memory
6419 for the current vCPU state.  KVM maps memory     6419 for the current vCPU state.  KVM maps memory as if the vCPU generated a
6420 stage-2 read page fault, e.g. faults in memor    6420 stage-2 read page fault, e.g. faults in memory as needed, but doesn't break
6421 CoW.  However, KVM does not mark any newly cr    6421 CoW.  However, KVM does not mark any newly created stage-2 PTE as Accessed.
6422                                                  6422 
6423 In the case of confidential VM types where th    6423 In the case of confidential VM types where there is an initial set up of
6424 private guest memory before the guest is 'fin    6424 private guest memory before the guest is 'finalized'/measured, this ioctl
6425 should only be issued after completing all th    6425 should only be issued after completing all the necessary setup to put the
6426 guest into a 'finalized' state so that the ab    6426 guest into a 'finalized' state so that the above semantics can be reliably
6427 ensured.                                         6427 ensured.
6428                                                  6428 
6429 In some cases, multiple vCPUs might share the    6429 In some cases, multiple vCPUs might share the page tables.  In this
6430 case, the ioctl can be called in parallel.       6430 case, the ioctl can be called in parallel.
6431                                                  6431 
6432 When the ioctl returns, the input values are     6432 When the ioctl returns, the input values are updated to point to the
6433 remaining range.  If `size` > 0 on return, th    6433 remaining range.  If `size` > 0 on return, the caller can just issue
6434 the ioctl again with the same `struct kvm_map    6434 the ioctl again with the same `struct kvm_map_memory` argument.
6435                                                  6435 
6436 Shadow page tables cannot support this ioctl     6436 Shadow page tables cannot support this ioctl because they
6437 are indexed by virtual address or nested gues    6437 are indexed by virtual address or nested guest physical address.
6438 Calling this ioctl when the guest is using sh    6438 Calling this ioctl when the guest is using shadow page tables (for
6439 example because it is running a nested guest     6439 example because it is running a nested guest with nested page tables)
6440 will fail with `EOPNOTSUPP` even if `KVM_CHEC    6440 will fail with `EOPNOTSUPP` even if `KVM_CHECK_EXTENSION` reports
6441 the capability to be present.                    6441 the capability to be present.
6442                                                  6442 
6443 `flags` must currently be zero.                  6443 `flags` must currently be zero.
6444                                                  6444 
6445                                                  6445 
6446 5. The kvm_run structure                         6446 5. The kvm_run structure
6447 ========================                         6447 ========================
6448                                                  6448 
6449 Application code obtains a pointer to the kvm    6449 Application code obtains a pointer to the kvm_run structure by
6450 mmap()ing a vcpu fd.  From that point, applic    6450 mmap()ing a vcpu fd.  From that point, application code can control
6451 execution by changing fields in kvm_run prior    6451 execution by changing fields in kvm_run prior to calling the KVM_RUN
6452 ioctl, and obtain information about the reaso    6452 ioctl, and obtain information about the reason KVM_RUN returned by
6453 looking up structure members.                    6453 looking up structure members.
6454                                                  6454 
6455 ::                                               6455 ::
6456                                                  6456 
6457   struct kvm_run {                               6457   struct kvm_run {
6458         /* in */                                 6458         /* in */
6459         __u8 request_interrupt_window;           6459         __u8 request_interrupt_window;
6460                                                  6460 
6461 Request that KVM_RUN return when it becomes p    6461 Request that KVM_RUN return when it becomes possible to inject external
6462 interrupts into the guest.  Useful in conjunc    6462 interrupts into the guest.  Useful in conjunction with KVM_INTERRUPT.
6463                                                  6463 
6464 ::                                               6464 ::
6465                                                  6465 
6466         __u8 immediate_exit;                     6466         __u8 immediate_exit;
6467                                                  6467 
6468 This field is polled once when KVM_RUN starts    6468 This field is polled once when KVM_RUN starts; if non-zero, KVM_RUN
6469 exits immediately, returning -EINTR.  In the     6469 exits immediately, returning -EINTR.  In the common scenario where a
6470 signal is used to "kick" a VCPU out of KVM_RU    6470 signal is used to "kick" a VCPU out of KVM_RUN, this field can be used
6471 to avoid usage of KVM_SET_SIGNAL_MASK, which     6471 to avoid usage of KVM_SET_SIGNAL_MASK, which has worse scalability.
6472 Rather than blocking the signal outside KVM_R    6472 Rather than blocking the signal outside KVM_RUN, userspace can set up
6473 a signal handler that sets run->immediate_exi    6473 a signal handler that sets run->immediate_exit to a non-zero value.
6474                                                  6474 
6475 This field is ignored if KVM_CAP_IMMEDIATE_EX    6475 This field is ignored if KVM_CAP_IMMEDIATE_EXIT is not available.
6476                                                  6476 
6477 ::                                               6477 ::
6478                                                  6478 
6479         __u8 padding1[6];                        6479         __u8 padding1[6];
6480                                                  6480 
6481         /* out */                                6481         /* out */
6482         __u32 exit_reason;                       6482         __u32 exit_reason;
6483                                                  6483 
6484 When KVM_RUN has returned successfully (retur    6484 When KVM_RUN has returned successfully (return value 0), this informs
6485 application code why KVM_RUN has returned.  A    6485 application code why KVM_RUN has returned.  Allowable values for this
6486 field are detailed below.                        6486 field are detailed below.
6487                                                  6487 
6488 ::                                               6488 ::
6489                                                  6489 
6490         __u8 ready_for_interrupt_injection;      6490         __u8 ready_for_interrupt_injection;
6491                                                  6491 
6492 If request_interrupt_window has been specifie    6492 If request_interrupt_window has been specified, this field indicates
6493 an interrupt can be injected now with KVM_INT    6493 an interrupt can be injected now with KVM_INTERRUPT.
6494                                                  6494 
6495 ::                                               6495 ::
6496                                                  6496 
6497         __u8 if_flag;                            6497         __u8 if_flag;
6498                                                  6498 
6499 The value of the current interrupt flag.  Onl    6499 The value of the current interrupt flag.  Only valid if in-kernel
6500 local APIC is not used.                          6500 local APIC is not used.
6501                                                  6501 
6502 ::                                               6502 ::
6503                                                  6503 
6504         __u16 flags;                             6504         __u16 flags;
6505                                                  6505 
6506 More architecture-specific flags detailing st    6506 More architecture-specific flags detailing state of the VCPU that may
6507 affect the device's behavior. Current defined    6507 affect the device's behavior. Current defined flags::
6508                                                  6508 
6509   /* x86, set if the VCPU is in system manage    6509   /* x86, set if the VCPU is in system management mode */
6510   #define KVM_RUN_X86_SMM          (1 << 0)      6510   #define KVM_RUN_X86_SMM          (1 << 0)
6511   /* x86, set if bus lock detected in VM */      6511   /* x86, set if bus lock detected in VM */
6512   #define KVM_RUN_X86_BUS_LOCK     (1 << 1)      6512   #define KVM_RUN_X86_BUS_LOCK     (1 << 1)
6513   /* x86, set if the VCPU is executing a nest    6513   /* x86, set if the VCPU is executing a nested (L2) guest */
6514   #define KVM_RUN_X86_GUEST_MODE   (1 << 2)      6514   #define KVM_RUN_X86_GUEST_MODE   (1 << 2)
6515                                                  6515 
6516   /* arm64, set for KVM_EXIT_DEBUG */            6516   /* arm64, set for KVM_EXIT_DEBUG */
6517   #define KVM_DEBUG_ARCH_HSR_HIGH_VALID  (1 <    6517   #define KVM_DEBUG_ARCH_HSR_HIGH_VALID  (1 << 0)
6518                                                  6518 
6519 ::                                               6519 ::
6520                                                  6520 
6521         /* in (pre_kvm_run), out (post_kvm_ru    6521         /* in (pre_kvm_run), out (post_kvm_run) */
6522         __u64 cr8;                               6522         __u64 cr8;
6523                                                  6523 
6524 The value of the cr8 register.  Only valid if    6524 The value of the cr8 register.  Only valid if in-kernel local APIC is
6525 not used.  Both input and output.                6525 not used.  Both input and output.
6526                                                  6526 
6527 ::                                               6527 ::
6528                                                  6528 
6529         __u64 apic_base;                         6529         __u64 apic_base;
6530                                                  6530 
6531 The value of the APIC BASE msr.  Only valid i    6531 The value of the APIC BASE msr.  Only valid if in-kernel local
6532 APIC is not used.  Both input and output.        6532 APIC is not used.  Both input and output.
6533                                                  6533 
6534 ::                                               6534 ::
6535                                                  6535 
6536         union {                                  6536         union {
6537                 /* KVM_EXIT_UNKNOWN */           6537                 /* KVM_EXIT_UNKNOWN */
6538                 struct {                         6538                 struct {
6539                         __u64 hardware_exit_r    6539                         __u64 hardware_exit_reason;
6540                 } hw;                            6540                 } hw;
6541                                                  6541 
6542 If exit_reason is KVM_EXIT_UNKNOWN, the vcpu     6542 If exit_reason is KVM_EXIT_UNKNOWN, the vcpu has exited due to unknown
6543 reasons.  Further architecture-specific infor    6543 reasons.  Further architecture-specific information is available in
6544 hardware_exit_reason.                            6544 hardware_exit_reason.
6545                                                  6545 
6546 ::                                               6546 ::
6547                                                  6547 
6548                 /* KVM_EXIT_FAIL_ENTRY */        6548                 /* KVM_EXIT_FAIL_ENTRY */
6549                 struct {                         6549                 struct {
6550                         __u64 hardware_entry_    6550                         __u64 hardware_entry_failure_reason;
6551                         __u32 cpu; /* if KVM_    6551                         __u32 cpu; /* if KVM_LAST_CPU */
6552                 } fail_entry;                    6552                 } fail_entry;
6553                                                  6553 
6554 If exit_reason is KVM_EXIT_FAIL_ENTRY, the vc    6554 If exit_reason is KVM_EXIT_FAIL_ENTRY, the vcpu could not be run due
6555 to unknown reasons.  Further architecture-spe    6555 to unknown reasons.  Further architecture-specific information is
6556 available in hardware_entry_failure_reason.      6556 available in hardware_entry_failure_reason.
6557                                                  6557 
6558 ::                                               6558 ::
6559                                                  6559 
6560                 /* KVM_EXIT_EXCEPTION */         6560                 /* KVM_EXIT_EXCEPTION */
6561                 struct {                         6561                 struct {
6562                         __u32 exception;         6562                         __u32 exception;
6563                         __u32 error_code;        6563                         __u32 error_code;
6564                 } ex;                            6564                 } ex;
6565                                                  6565 
6566 Unused.                                          6566 Unused.
6567                                                  6567 
6568 ::                                               6568 ::
6569                                                  6569 
6570                 /* KVM_EXIT_IO */                6570                 /* KVM_EXIT_IO */
6571                 struct {                         6571                 struct {
6572   #define KVM_EXIT_IO_IN  0                      6572   #define KVM_EXIT_IO_IN  0
6573   #define KVM_EXIT_IO_OUT 1                      6573   #define KVM_EXIT_IO_OUT 1
6574                         __u8 direction;          6574                         __u8 direction;
6575                         __u8 size; /* bytes *    6575                         __u8 size; /* bytes */
6576                         __u16 port;              6576                         __u16 port;
6577                         __u32 count;             6577                         __u32 count;
6578                         __u64 data_offset; /*    6578                         __u64 data_offset; /* relative to kvm_run start */
6579                 } io;                            6579                 } io;
6580                                                  6580 
6581 If exit_reason is KVM_EXIT_IO, then the vcpu     6581 If exit_reason is KVM_EXIT_IO, then the vcpu has
6582 executed a port I/O instruction which could n    6582 executed a port I/O instruction which could not be satisfied by kvm.
6583 data_offset describes where the data is locat    6583 data_offset describes where the data is located (KVM_EXIT_IO_OUT) or
6584 where kvm expects application code to place t    6584 where kvm expects application code to place the data for the next
6585 KVM_RUN invocation (KVM_EXIT_IO_IN).  Data fo    6585 KVM_RUN invocation (KVM_EXIT_IO_IN).  Data format is a packed array.
6586                                                  6586 
6587 ::                                               6587 ::
6588                                                  6588 
6589                 /* KVM_EXIT_DEBUG */             6589                 /* KVM_EXIT_DEBUG */
6590                 struct {                         6590                 struct {
6591                         struct kvm_debug_exit    6591                         struct kvm_debug_exit_arch arch;
6592                 } debug;                         6592                 } debug;
6593                                                  6593 
6594 If the exit_reason is KVM_EXIT_DEBUG, then a     6594 If the exit_reason is KVM_EXIT_DEBUG, then a vcpu is processing a debug event
6595 for which architecture specific information i    6595 for which architecture specific information is returned.
6596                                                  6596 
6597 ::                                               6597 ::
6598                                                  6598 
6599                 /* KVM_EXIT_MMIO */              6599                 /* KVM_EXIT_MMIO */
6600                 struct {                         6600                 struct {
6601                         __u64 phys_addr;         6601                         __u64 phys_addr;
6602                         __u8  data[8];           6602                         __u8  data[8];
6603                         __u32 len;               6603                         __u32 len;
6604                         __u8  is_write;          6604                         __u8  is_write;
6605                 } mmio;                          6605                 } mmio;
6606                                                  6606 
6607 If exit_reason is KVM_EXIT_MMIO, then the vcp    6607 If exit_reason is KVM_EXIT_MMIO, then the vcpu has
6608 executed a memory-mapped I/O instruction whic    6608 executed a memory-mapped I/O instruction which could not be satisfied
6609 by kvm.  The 'data' member contains the writt    6609 by kvm.  The 'data' member contains the written data if 'is_write' is
6610 true, and should be filled by application cod    6610 true, and should be filled by application code otherwise.
6611                                                  6611 
6612 The 'data' member contains, in its first 'len    6612 The 'data' member contains, in its first 'len' bytes, the value as it would
6613 appear if the VCPU performed a load or store     6613 appear if the VCPU performed a load or store of the appropriate width directly
6614 to the byte array.                               6614 to the byte array.
6615                                                  6615 
6616 .. note::                                        6616 .. note::
6617                                                  6617 
6618       For KVM_EXIT_IO, KVM_EXIT_MMIO, KVM_EXI    6618       For KVM_EXIT_IO, KVM_EXIT_MMIO, KVM_EXIT_OSI, KVM_EXIT_PAPR, KVM_EXIT_XEN,
6619       KVM_EXIT_EPR, KVM_EXIT_X86_RDMSR and KV    6619       KVM_EXIT_EPR, KVM_EXIT_X86_RDMSR and KVM_EXIT_X86_WRMSR the corresponding
6620       operations are complete (and guest stat    6620       operations are complete (and guest state is consistent) only after userspace
6621       has re-entered the kernel with KVM_RUN.    6621       has re-entered the kernel with KVM_RUN.  The kernel side will first finish
6622       incomplete operations and then check fo    6622       incomplete operations and then check for pending signals.
6623                                                  6623 
6624       The pending state of the operation is n    6624       The pending state of the operation is not preserved in state which is
6625       visible to userspace, thus userspace sh    6625       visible to userspace, thus userspace should ensure that the operation is
6626       completed before performing a live migr    6626       completed before performing a live migration.  Userspace can re-enter the
6627       guest with an unmasked signal pending o    6627       guest with an unmasked signal pending or with the immediate_exit field set
6628       to complete pending operations without     6628       to complete pending operations without allowing any further instructions
6629       to be executed.                            6629       to be executed.
6630                                                  6630 
6631 ::                                               6631 ::
6632                                                  6632 
6633                 /* KVM_EXIT_HYPERCALL */         6633                 /* KVM_EXIT_HYPERCALL */
6634                 struct {                         6634                 struct {
6635                         __u64 nr;                6635                         __u64 nr;
6636                         __u64 args[6];           6636                         __u64 args[6];
6637                         __u64 ret;               6637                         __u64 ret;
6638                         __u64 flags;             6638                         __u64 flags;
6639                 } hypercall;                     6639                 } hypercall;
6640                                                  6640 
6641                                                  6641 
6642 It is strongly recommended that userspace use    6642 It is strongly recommended that userspace use ``KVM_EXIT_IO`` (x86) or
6643 ``KVM_EXIT_MMIO`` (all except s390) to implem    6643 ``KVM_EXIT_MMIO`` (all except s390) to implement functionality that
6644 requires a guest to interact with host usersp    6644 requires a guest to interact with host userspace.
6645                                                  6645 
6646 .. note:: KVM_EXIT_IO is significantly faster    6646 .. note:: KVM_EXIT_IO is significantly faster than KVM_EXIT_MMIO.
6647                                                  6647 
6648 For arm64:                                       6648 For arm64:
6649 ----------                                       6649 ----------
6650                                                  6650 
6651 SMCCC exits can be enabled depending on the c    6651 SMCCC exits can be enabled depending on the configuration of the SMCCC
6652 filter. See the Documentation/virt/kvm/device    6652 filter. See the Documentation/virt/kvm/devices/vm.rst
6653 ``KVM_ARM_SMCCC_FILTER`` for more details.       6653 ``KVM_ARM_SMCCC_FILTER`` for more details.
6654                                                  6654 
6655 ``nr`` contains the function ID of the guest'    6655 ``nr`` contains the function ID of the guest's SMCCC call. Userspace is
6656 expected to use the ``KVM_GET_ONE_REG`` ioctl    6656 expected to use the ``KVM_GET_ONE_REG`` ioctl to retrieve the call
6657 parameters from the vCPU's GPRs.                 6657 parameters from the vCPU's GPRs.
6658                                                  6658 
6659 Definition of ``flags``:                         6659 Definition of ``flags``:
6660  - ``KVM_HYPERCALL_EXIT_SMC``: Indicates that    6660  - ``KVM_HYPERCALL_EXIT_SMC``: Indicates that the guest used the SMC
6661    conduit to initiate the SMCCC call. If thi    6661    conduit to initiate the SMCCC call. If this bit is 0 then the guest
6662    used the HVC conduit for the SMCCC call.      6662    used the HVC conduit for the SMCCC call.
6663                                                  6663 
6664  - ``KVM_HYPERCALL_EXIT_16BIT``: Indicates th    6664  - ``KVM_HYPERCALL_EXIT_16BIT``: Indicates that the guest used a 16bit
6665    instruction to initiate the SMCCC call. If    6665    instruction to initiate the SMCCC call. If this bit is 0 then the
6666    guest used a 32bit instruction. An AArch64    6666    guest used a 32bit instruction. An AArch64 guest always has this
6667    bit set to 0.                                 6667    bit set to 0.
6668                                                  6668 
6669 At the point of exit, PC points to the instru    6669 At the point of exit, PC points to the instruction immediately following
6670 the trapping instruction.                        6670 the trapping instruction.
6671                                                  6671 
6672 ::                                               6672 ::
6673                                                  6673 
6674                 /* KVM_EXIT_TPR_ACCESS */        6674                 /* KVM_EXIT_TPR_ACCESS */
6675                 struct {                         6675                 struct {
6676                         __u64 rip;               6676                         __u64 rip;
6677                         __u32 is_write;          6677                         __u32 is_write;
6678                         __u32 pad;               6678                         __u32 pad;
6679                 } tpr_access;                    6679                 } tpr_access;
6680                                                  6680 
6681 To be documented (KVM_TPR_ACCESS_REPORTING).     6681 To be documented (KVM_TPR_ACCESS_REPORTING).
6682                                                  6682 
6683 ::                                               6683 ::
6684                                                  6684 
6685                 /* KVM_EXIT_S390_SIEIC */        6685                 /* KVM_EXIT_S390_SIEIC */
6686                 struct {                         6686                 struct {
6687                         __u8 icptcode;           6687                         __u8 icptcode;
6688                         __u64 mask; /* psw up    6688                         __u64 mask; /* psw upper half */
6689                         __u64 addr; /* psw lo    6689                         __u64 addr; /* psw lower half */
6690                         __u16 ipa;               6690                         __u16 ipa;
6691                         __u32 ipb;               6691                         __u32 ipb;
6692                 } s390_sieic;                    6692                 } s390_sieic;
6693                                                  6693 
6694 s390 specific.                                   6694 s390 specific.
6695                                                  6695 
6696 ::                                               6696 ::
6697                                                  6697 
6698                 /* KVM_EXIT_S390_RESET */        6698                 /* KVM_EXIT_S390_RESET */
6699   #define KVM_S390_RESET_POR       1             6699   #define KVM_S390_RESET_POR       1
6700   #define KVM_S390_RESET_CLEAR     2             6700   #define KVM_S390_RESET_CLEAR     2
6701   #define KVM_S390_RESET_SUBSYSTEM 4             6701   #define KVM_S390_RESET_SUBSYSTEM 4
6702   #define KVM_S390_RESET_CPU_INIT  8             6702   #define KVM_S390_RESET_CPU_INIT  8
6703   #define KVM_S390_RESET_IPL       16            6703   #define KVM_S390_RESET_IPL       16
6704                 __u64 s390_reset_flags;          6704                 __u64 s390_reset_flags;
6705                                                  6705 
6706 s390 specific.                                   6706 s390 specific.
6707                                                  6707 
6708 ::                                               6708 ::
6709                                                  6709 
6710                 /* KVM_EXIT_S390_UCONTROL */     6710                 /* KVM_EXIT_S390_UCONTROL */
6711                 struct {                         6711                 struct {
6712                         __u64 trans_exc_code;    6712                         __u64 trans_exc_code;
6713                         __u32 pgm_code;          6713                         __u32 pgm_code;
6714                 } s390_ucontrol;                 6714                 } s390_ucontrol;
6715                                                  6715 
6716 s390 specific. A page fault has occurred for     6716 s390 specific. A page fault has occurred for a user controlled virtual
6717 machine (KVM_VM_S390_UNCONTROL) on its host p    6717 machine (KVM_VM_S390_UNCONTROL) on its host page table that cannot be
6718 resolved by the kernel.                          6718 resolved by the kernel.
6719 The program code and the translation exceptio    6719 The program code and the translation exception code that were placed
6720 in the cpu's lowcore are presented here as de    6720 in the cpu's lowcore are presented here as defined by the z Architecture
6721 Principles of Operation Book in the Chapter f    6721 Principles of Operation Book in the Chapter for Dynamic Address Translation
6722 (DAT)                                            6722 (DAT)
6723                                                  6723 
6724 ::                                               6724 ::
6725                                                  6725 
6726                 /* KVM_EXIT_DCR */               6726                 /* KVM_EXIT_DCR */
6727                 struct {                         6727                 struct {
6728                         __u32 dcrn;              6728                         __u32 dcrn;
6729                         __u32 data;              6729                         __u32 data;
6730                         __u8  is_write;          6730                         __u8  is_write;
6731                 } dcr;                           6731                 } dcr;
6732                                                  6732 
6733 Deprecated - was used for 440 KVM.               6733 Deprecated - was used for 440 KVM.
6734                                                  6734 
6735 ::                                               6735 ::
6736                                                  6736 
6737                 /* KVM_EXIT_OSI */               6737                 /* KVM_EXIT_OSI */
6738                 struct {                         6738                 struct {
6739                         __u64 gprs[32];          6739                         __u64 gprs[32];
6740                 } osi;                           6740                 } osi;
6741                                                  6741 
6742 MOL uses a special hypercall interface it cal    6742 MOL uses a special hypercall interface it calls 'OSI'. To enable it, we catch
6743 hypercalls and exit with this exit struct tha    6743 hypercalls and exit with this exit struct that contains all the guest gprs.
6744                                                  6744 
6745 If exit_reason is KVM_EXIT_OSI, then the vcpu    6745 If exit_reason is KVM_EXIT_OSI, then the vcpu has triggered such a hypercall.
6746 Userspace can now handle the hypercall and wh    6746 Userspace can now handle the hypercall and when it's done modify the gprs as
6747 necessary. Upon guest entry all guest GPRs wi    6747 necessary. Upon guest entry all guest GPRs will then be replaced by the values
6748 in this struct.                                  6748 in this struct.
6749                                                  6749 
6750 ::                                               6750 ::
6751                                                  6751 
6752                 /* KVM_EXIT_PAPR_HCALL */        6752                 /* KVM_EXIT_PAPR_HCALL */
6753                 struct {                         6753                 struct {
6754                         __u64 nr;                6754                         __u64 nr;
6755                         __u64 ret;               6755                         __u64 ret;
6756                         __u64 args[9];           6756                         __u64 args[9];
6757                 } papr_hcall;                    6757                 } papr_hcall;
6758                                                  6758 
6759 This is used on 64-bit PowerPC when emulating    6759 This is used on 64-bit PowerPC when emulating a pSeries partition,
6760 e.g. with the 'pseries' machine type in qemu.    6760 e.g. with the 'pseries' machine type in qemu.  It occurs when the
6761 guest does a hypercall using the 'sc 1' instr    6761 guest does a hypercall using the 'sc 1' instruction.  The 'nr' field
6762 contains the hypercall number (from the guest    6762 contains the hypercall number (from the guest R3), and 'args' contains
6763 the arguments (from the guest R4 - R12).  Use    6763 the arguments (from the guest R4 - R12).  Userspace should put the
6764 return code in 'ret' and any extra returned v    6764 return code in 'ret' and any extra returned values in args[].
6765 The possible hypercalls are defined in the Po    6765 The possible hypercalls are defined in the Power Architecture Platform
6766 Requirements (PAPR) document available from w    6766 Requirements (PAPR) document available from www.power.org (free
6767 developer registration required to access it)    6767 developer registration required to access it).
6768                                                  6768 
6769 ::                                               6769 ::
6770                                                  6770 
6771                 /* KVM_EXIT_S390_TSCH */         6771                 /* KVM_EXIT_S390_TSCH */
6772                 struct {                         6772                 struct {
6773                         __u16 subchannel_id;     6773                         __u16 subchannel_id;
6774                         __u16 subchannel_nr;     6774                         __u16 subchannel_nr;
6775                         __u32 io_int_parm;       6775                         __u32 io_int_parm;
6776                         __u32 io_int_word;       6776                         __u32 io_int_word;
6777                         __u32 ipb;               6777                         __u32 ipb;
6778                         __u8 dequeued;           6778                         __u8 dequeued;
6779                 } s390_tsch;                     6779                 } s390_tsch;
6780                                                  6780 
6781 s390 specific. This exit occurs when KVM_CAP_    6781 s390 specific. This exit occurs when KVM_CAP_S390_CSS_SUPPORT has been enabled
6782 and TEST SUBCHANNEL was intercepted. If deque    6782 and TEST SUBCHANNEL was intercepted. If dequeued is set, a pending I/O
6783 interrupt for the target subchannel has been     6783 interrupt for the target subchannel has been dequeued and subchannel_id,
6784 subchannel_nr, io_int_parm and io_int_word co    6784 subchannel_nr, io_int_parm and io_int_word contain the parameters for that
6785 interrupt. ipb is needed for instruction para    6785 interrupt. ipb is needed for instruction parameter decoding.
6786                                                  6786 
6787 ::                                               6787 ::
6788                                                  6788 
6789                 /* KVM_EXIT_EPR */               6789                 /* KVM_EXIT_EPR */
6790                 struct {                         6790                 struct {
6791                         __u32 epr;               6791                         __u32 epr;
6792                 } epr;                           6792                 } epr;
6793                                                  6793 
6794 On FSL BookE PowerPC chips, the interrupt con    6794 On FSL BookE PowerPC chips, the interrupt controller has a fast patch
6795 interrupt acknowledge path to the core. When     6795 interrupt acknowledge path to the core. When the core successfully
6796 delivers an interrupt, it automatically popul    6796 delivers an interrupt, it automatically populates the EPR register with
6797 the interrupt vector number and acknowledges     6797 the interrupt vector number and acknowledges the interrupt inside
6798 the interrupt controller.                        6798 the interrupt controller.
6799                                                  6799 
6800 In case the interrupt controller lives in use    6800 In case the interrupt controller lives in user space, we need to do
6801 the interrupt acknowledge cycle through it to    6801 the interrupt acknowledge cycle through it to fetch the next to be
6802 delivered interrupt vector using this exit.      6802 delivered interrupt vector using this exit.
6803                                                  6803 
6804 It gets triggered whenever both KVM_CAP_PPC_E    6804 It gets triggered whenever both KVM_CAP_PPC_EPR are enabled and an
6805 external interrupt has just been delivered in    6805 external interrupt has just been delivered into the guest. User space
6806 should put the acknowledged interrupt vector     6806 should put the acknowledged interrupt vector into the 'epr' field.
6807                                                  6807 
6808 ::                                               6808 ::
6809                                                  6809 
6810                 /* KVM_EXIT_SYSTEM_EVENT */      6810                 /* KVM_EXIT_SYSTEM_EVENT */
6811                 struct {                         6811                 struct {
6812   #define KVM_SYSTEM_EVENT_SHUTDOWN       1      6812   #define KVM_SYSTEM_EVENT_SHUTDOWN       1
6813   #define KVM_SYSTEM_EVENT_RESET          2      6813   #define KVM_SYSTEM_EVENT_RESET          2
6814   #define KVM_SYSTEM_EVENT_CRASH          3      6814   #define KVM_SYSTEM_EVENT_CRASH          3
6815   #define KVM_SYSTEM_EVENT_WAKEUP         4      6815   #define KVM_SYSTEM_EVENT_WAKEUP         4
6816   #define KVM_SYSTEM_EVENT_SUSPEND        5      6816   #define KVM_SYSTEM_EVENT_SUSPEND        5
6817   #define KVM_SYSTEM_EVENT_SEV_TERM       6      6817   #define KVM_SYSTEM_EVENT_SEV_TERM       6
6818                         __u32 type;              6818                         __u32 type;
6819                         __u32 ndata;             6819                         __u32 ndata;
6820                         __u64 data[16];          6820                         __u64 data[16];
6821                 } system_event;                  6821                 } system_event;
6822                                                  6822 
6823 If exit_reason is KVM_EXIT_SYSTEM_EVENT then     6823 If exit_reason is KVM_EXIT_SYSTEM_EVENT then the vcpu has triggered
6824 a system-level event using some architecture     6824 a system-level event using some architecture specific mechanism (hypercall
6825 or some special instruction). In case of ARM6    6825 or some special instruction). In case of ARM64, this is triggered using
6826 HVC instruction based PSCI call from the vcpu    6826 HVC instruction based PSCI call from the vcpu.
6827                                                  6827 
6828 The 'type' field describes the system-level e    6828 The 'type' field describes the system-level event type.
6829 Valid values for 'type' are:                     6829 Valid values for 'type' are:
6830                                                  6830 
6831  - KVM_SYSTEM_EVENT_SHUTDOWN -- the guest has    6831  - KVM_SYSTEM_EVENT_SHUTDOWN -- the guest has requested a shutdown of the
6832    VM. Userspace is not obliged to honour thi    6832    VM. Userspace is not obliged to honour this, and if it does honour
6833    this does not need to destroy the VM synch    6833    this does not need to destroy the VM synchronously (ie it may call
6834    KVM_RUN again before shutdown finally occu    6834    KVM_RUN again before shutdown finally occurs).
6835  - KVM_SYSTEM_EVENT_RESET -- the guest has re    6835  - KVM_SYSTEM_EVENT_RESET -- the guest has requested a reset of the VM.
6836    As with SHUTDOWN, userspace can choose to     6836    As with SHUTDOWN, userspace can choose to ignore the request, or
6837    to schedule the reset to occur in the futu    6837    to schedule the reset to occur in the future and may call KVM_RUN again.
6838  - KVM_SYSTEM_EVENT_CRASH -- the guest crash     6838  - KVM_SYSTEM_EVENT_CRASH -- the guest crash occurred and the guest
6839    has requested a crash condition maintenanc    6839    has requested a crash condition maintenance. Userspace can choose
6840    to ignore the request, or to gather VM mem    6840    to ignore the request, or to gather VM memory core dump and/or
6841    reset/shutdown of the VM.                     6841    reset/shutdown of the VM.
6842  - KVM_SYSTEM_EVENT_SEV_TERM -- an AMD SEV gu    6842  - KVM_SYSTEM_EVENT_SEV_TERM -- an AMD SEV guest requested termination.
6843    The guest physical address of the guest's     6843    The guest physical address of the guest's GHCB is stored in `data[0]`.
6844  - KVM_SYSTEM_EVENT_WAKEUP -- the exiting vCP    6844  - KVM_SYSTEM_EVENT_WAKEUP -- the exiting vCPU is in a suspended state and
6845    KVM has recognized a wakeup event. Userspa    6845    KVM has recognized a wakeup event. Userspace may honor this event by
6846    marking the exiting vCPU as runnable, or d    6846    marking the exiting vCPU as runnable, or deny it and call KVM_RUN again.
6847  - KVM_SYSTEM_EVENT_SUSPEND -- the guest has     6847  - KVM_SYSTEM_EVENT_SUSPEND -- the guest has requested a suspension of
6848    the VM.                                       6848    the VM.
6849                                                  6849 
6850 If KVM_CAP_SYSTEM_EVENT_DATA is present, the     6850 If KVM_CAP_SYSTEM_EVENT_DATA is present, the 'data' field can contain
6851 architecture specific information for the sys    6851 architecture specific information for the system-level event.  Only
6852 the first `ndata` items (possibly zero) of th    6852 the first `ndata` items (possibly zero) of the data array are valid.
6853                                                  6853 
6854  - for arm64, data[0] is set to KVM_SYSTEM_EV    6854  - for arm64, data[0] is set to KVM_SYSTEM_EVENT_RESET_FLAG_PSCI_RESET2 if
6855    the guest issued a SYSTEM_RESET2 call acco    6855    the guest issued a SYSTEM_RESET2 call according to v1.1 of the PSCI
6856    specification.                                6856    specification.
6857                                                  6857 
6858  - for RISC-V, data[0] is set to the value of    6858  - for RISC-V, data[0] is set to the value of the second argument of the
6859    ``sbi_system_reset`` call.                    6859    ``sbi_system_reset`` call.
6860                                                  6860 
6861 Previous versions of Linux defined a `flags`     6861 Previous versions of Linux defined a `flags` member in this struct.  The
6862 field is now aliased to `data[0]`.  Userspace    6862 field is now aliased to `data[0]`.  Userspace can assume that it is only
6863 written if ndata is greater than 0.              6863 written if ndata is greater than 0.
6864                                                  6864 
6865 For arm/arm64:                                   6865 For arm/arm64:
6866 --------------                                   6866 --------------
6867                                                  6867 
6868 KVM_SYSTEM_EVENT_SUSPEND exits are enabled wi    6868 KVM_SYSTEM_EVENT_SUSPEND exits are enabled with the
6869 KVM_CAP_ARM_SYSTEM_SUSPEND VM capability. If     6869 KVM_CAP_ARM_SYSTEM_SUSPEND VM capability. If a guest invokes the PSCI
6870 SYSTEM_SUSPEND function, KVM will exit to use    6870 SYSTEM_SUSPEND function, KVM will exit to userspace with this event
6871 type.                                            6871 type.
6872                                                  6872 
6873 It is the sole responsibility of userspace to    6873 It is the sole responsibility of userspace to implement the PSCI
6874 SYSTEM_SUSPEND call according to ARM DEN0022D    6874 SYSTEM_SUSPEND call according to ARM DEN0022D.b 5.19 "SYSTEM_SUSPEND".
6875 KVM does not change the vCPU's state before e    6875 KVM does not change the vCPU's state before exiting to userspace, so
6876 the call parameters are left in-place in the     6876 the call parameters are left in-place in the vCPU registers.
6877                                                  6877 
6878 Userspace is _required_ to take action for su    6878 Userspace is _required_ to take action for such an exit. It must
6879 either:                                          6879 either:
6880                                                  6880 
6881  - Honor the guest request to suspend the VM.    6881  - Honor the guest request to suspend the VM. Userspace can request
6882    in-kernel emulation of suspension by setti    6882    in-kernel emulation of suspension by setting the calling vCPU's
6883    state to KVM_MP_STATE_SUSPENDED. Userspace    6883    state to KVM_MP_STATE_SUSPENDED. Userspace must configure the vCPU's
6884    state according to the parameters passed t    6884    state according to the parameters passed to the PSCI function when
6885    the calling vCPU is resumed. See ARM DEN00    6885    the calling vCPU is resumed. See ARM DEN0022D.b 5.19.1 "Intended use"
6886    for details on the function parameters.       6886    for details on the function parameters.
6887                                                  6887 
6888  - Deny the guest request to suspend the VM.     6888  - Deny the guest request to suspend the VM. See ARM DEN0022D.b 5.19.2
6889    "Caller responsibilities" for possible ret    6889    "Caller responsibilities" for possible return values.
6890                                                  6890 
6891 ::                                               6891 ::
6892                                                  6892 
6893                 /* KVM_EXIT_IOAPIC_EOI */        6893                 /* KVM_EXIT_IOAPIC_EOI */
6894                 struct {                         6894                 struct {
6895                         __u8 vector;             6895                         __u8 vector;
6896                 } eoi;                           6896                 } eoi;
6897                                                  6897 
6898 Indicates that the VCPU's in-kernel local API    6898 Indicates that the VCPU's in-kernel local APIC received an EOI for a
6899 level-triggered IOAPIC interrupt.  This exit     6899 level-triggered IOAPIC interrupt.  This exit only triggers when the
6900 IOAPIC is implemented in userspace (i.e. KVM_    6900 IOAPIC is implemented in userspace (i.e. KVM_CAP_SPLIT_IRQCHIP is enabled);
6901 the userspace IOAPIC should process the EOI a    6901 the userspace IOAPIC should process the EOI and retrigger the interrupt if
6902 it is still asserted.  Vector is the LAPIC in    6902 it is still asserted.  Vector is the LAPIC interrupt vector for which the
6903 EOI was received.                                6903 EOI was received.
6904                                                  6904 
6905 ::                                               6905 ::
6906                                                  6906 
6907                 struct kvm_hyperv_exit {         6907                 struct kvm_hyperv_exit {
6908   #define KVM_EXIT_HYPERV_SYNIC          1       6908   #define KVM_EXIT_HYPERV_SYNIC          1
6909   #define KVM_EXIT_HYPERV_HCALL          2       6909   #define KVM_EXIT_HYPERV_HCALL          2
6910   #define KVM_EXIT_HYPERV_SYNDBG         3       6910   #define KVM_EXIT_HYPERV_SYNDBG         3
6911                         __u32 type;              6911                         __u32 type;
6912                         __u32 pad1;              6912                         __u32 pad1;
6913                         union {                  6913                         union {
6914                                 struct {         6914                                 struct {
6915                                         __u32    6915                                         __u32 msr;
6916                                         __u32    6916                                         __u32 pad2;
6917                                         __u64    6917                                         __u64 control;
6918                                         __u64    6918                                         __u64 evt_page;
6919                                         __u64    6919                                         __u64 msg_page;
6920                                 } synic;         6920                                 } synic;
6921                                 struct {         6921                                 struct {
6922                                         __u64    6922                                         __u64 input;
6923                                         __u64    6923                                         __u64 result;
6924                                         __u64    6924                                         __u64 params[2];
6925                                 } hcall;         6925                                 } hcall;
6926                                 struct {         6926                                 struct {
6927                                         __u32    6927                                         __u32 msr;
6928                                         __u32    6928                                         __u32 pad2;
6929                                         __u64    6929                                         __u64 control;
6930                                         __u64    6930                                         __u64 status;
6931                                         __u64    6931                                         __u64 send_page;
6932                                         __u64    6932                                         __u64 recv_page;
6933                                         __u64    6933                                         __u64 pending_page;
6934                                 } syndbg;        6934                                 } syndbg;
6935                         } u;                     6935                         } u;
6936                 };                               6936                 };
6937                 /* KVM_EXIT_HYPERV */            6937                 /* KVM_EXIT_HYPERV */
6938                 struct kvm_hyperv_exit hyperv    6938                 struct kvm_hyperv_exit hyperv;
6939                                                  6939 
6940 Indicates that the VCPU exits into userspace     6940 Indicates that the VCPU exits into userspace to process some tasks
6941 related to Hyper-V emulation.                    6941 related to Hyper-V emulation.
6942                                                  6942 
6943 Valid values for 'type' are:                     6943 Valid values for 'type' are:
6944                                                  6944 
6945         - KVM_EXIT_HYPERV_SYNIC -- synchronou    6945         - KVM_EXIT_HYPERV_SYNIC -- synchronously notify user-space about
6946                                                  6946 
6947 Hyper-V SynIC state change. Notification is u    6947 Hyper-V SynIC state change. Notification is used to remap SynIC
6948 event/message pages and to enable/disable Syn    6948 event/message pages and to enable/disable SynIC messages/events processing
6949 in userspace.                                    6949 in userspace.
6950                                                  6950 
6951         - KVM_EXIT_HYPERV_SYNDBG -- synchrono    6951         - KVM_EXIT_HYPERV_SYNDBG -- synchronously notify user-space about
6952                                                  6952 
6953 Hyper-V Synthetic debugger state change. Noti    6953 Hyper-V Synthetic debugger state change. Notification is used to either update
6954 the pending_page location or to send a contro    6954 the pending_page location or to send a control command (send the buffer located
6955 in send_page or recv a buffer to recv_page).     6955 in send_page or recv a buffer to recv_page).
6956                                                  6956 
6957 ::                                               6957 ::
6958                                                  6958 
6959                 /* KVM_EXIT_ARM_NISV */          6959                 /* KVM_EXIT_ARM_NISV */
6960                 struct {                         6960                 struct {
6961                         __u64 esr_iss;           6961                         __u64 esr_iss;
6962                         __u64 fault_ipa;         6962                         __u64 fault_ipa;
6963                 } arm_nisv;                      6963                 } arm_nisv;
6964                                                  6964 
6965 Used on arm64 systems. If a guest accesses me    6965 Used on arm64 systems. If a guest accesses memory not in a memslot,
6966 KVM will typically return to userspace and as    6966 KVM will typically return to userspace and ask it to do MMIO emulation on its
6967 behalf. However, for certain classes of instr    6967 behalf. However, for certain classes of instructions, no instruction decode
6968 (direction, length of memory access) is provi    6968 (direction, length of memory access) is provided, and fetching and decoding
6969 the instruction from the VM is overly complic    6969 the instruction from the VM is overly complicated to live in the kernel.
6970                                                  6970 
6971 Historically, when this situation occurred, K    6971 Historically, when this situation occurred, KVM would print a warning and kill
6972 the VM. KVM assumed that if the guest accesse    6972 the VM. KVM assumed that if the guest accessed non-memslot memory, it was
6973 trying to do I/O, which just couldn't be emul    6973 trying to do I/O, which just couldn't be emulated, and the warning message was
6974 phrased accordingly. However, what happened m    6974 phrased accordingly. However, what happened more often was that a guest bug
6975 caused access outside the guest memory areas     6975 caused access outside the guest memory areas which should lead to a more
6976 meaningful warning message and an external ab    6976 meaningful warning message and an external abort in the guest, if the access
6977 did not fall within an I/O window.               6977 did not fall within an I/O window.
6978                                                  6978 
6979 Userspace implementations can query for KVM_C    6979 Userspace implementations can query for KVM_CAP_ARM_NISV_TO_USER, and enable
6980 this capability at VM creation. Once this is     6980 this capability at VM creation. Once this is done, these types of errors will
6981 instead return to userspace with KVM_EXIT_ARM    6981 instead return to userspace with KVM_EXIT_ARM_NISV, with the valid bits from
6982 the ESR_EL2 in the esr_iss field, and the fau    6982 the ESR_EL2 in the esr_iss field, and the faulting IPA in the fault_ipa field.
6983 Userspace can either fix up the access if it'    6983 Userspace can either fix up the access if it's actually an I/O access by
6984 decoding the instruction from guest memory (i    6984 decoding the instruction from guest memory (if it's very brave) and continue
6985 executing the guest, or it can decide to susp    6985 executing the guest, or it can decide to suspend, dump, or restart the guest.
6986                                                  6986 
6987 Note that KVM does not skip the faulting inst    6987 Note that KVM does not skip the faulting instruction as it does for
6988 KVM_EXIT_MMIO, but userspace has to emulate a    6988 KVM_EXIT_MMIO, but userspace has to emulate any change to the processing state
6989 if it decides to decode and emulate the instr    6989 if it decides to decode and emulate the instruction.
6990                                                  6990 
6991 This feature isn't available to protected VMs    6991 This feature isn't available to protected VMs, as userspace does not
6992 have access to the state that is required to     6992 have access to the state that is required to perform the emulation.
6993 Instead, a data abort exception is directly i    6993 Instead, a data abort exception is directly injected in the guest.
6994 Note that although KVM_CAP_ARM_NISV_TO_USER w    6994 Note that although KVM_CAP_ARM_NISV_TO_USER will be reported if
6995 queried outside of a protected VM context, th    6995 queried outside of a protected VM context, the feature will not be
6996 exposed if queried on a protected VM file des    6996 exposed if queried on a protected VM file descriptor.
6997                                                  6997 
6998 ::                                               6998 ::
6999                                                  6999 
7000                 /* KVM_EXIT_X86_RDMSR / KVM_E    7000                 /* KVM_EXIT_X86_RDMSR / KVM_EXIT_X86_WRMSR */
7001                 struct {                         7001                 struct {
7002                         __u8 error; /* user -    7002                         __u8 error; /* user -> kernel */
7003                         __u8 pad[7];             7003                         __u8 pad[7];
7004                         __u32 reason; /* kern    7004                         __u32 reason; /* kernel -> user */
7005                         __u32 index; /* kerne    7005                         __u32 index; /* kernel -> user */
7006                         __u64 data; /* kernel    7006                         __u64 data; /* kernel <-> user */
7007                 } msr;                           7007                 } msr;
7008                                                  7008 
7009 Used on x86 systems. When the VM capability K    7009 Used on x86 systems. When the VM capability KVM_CAP_X86_USER_SPACE_MSR is
7010 enabled, MSR accesses to registers that would    7010 enabled, MSR accesses to registers that would invoke a #GP by KVM kernel code
7011 may instead trigger a KVM_EXIT_X86_RDMSR exit    7011 may instead trigger a KVM_EXIT_X86_RDMSR exit for reads and KVM_EXIT_X86_WRMSR
7012 exit for writes.                                 7012 exit for writes.
7013                                                  7013 
7014 The "reason" field specifies why the MSR inte    7014 The "reason" field specifies why the MSR interception occurred. Userspace will
7015 only receive MSR exits when a particular reas    7015 only receive MSR exits when a particular reason was requested during through
7016 ENABLE_CAP. Currently valid exit reasons are:    7016 ENABLE_CAP. Currently valid exit reasons are:
7017                                                  7017 
7018 ============================ ================    7018 ============================ ========================================
7019  KVM_MSR_EXIT_REASON_UNKNOWN access to MSR th    7019  KVM_MSR_EXIT_REASON_UNKNOWN access to MSR that is unknown to KVM
7020  KVM_MSR_EXIT_REASON_INVAL   access to invali    7020  KVM_MSR_EXIT_REASON_INVAL   access to invalid MSRs or reserved bits
7021  KVM_MSR_EXIT_REASON_FILTER  access blocked b    7021  KVM_MSR_EXIT_REASON_FILTER  access blocked by KVM_X86_SET_MSR_FILTER
7022 ============================ ================    7022 ============================ ========================================
7023                                                  7023 
7024 For KVM_EXIT_X86_RDMSR, the "index" field tel    7024 For KVM_EXIT_X86_RDMSR, the "index" field tells userspace which MSR the guest
7025 wants to read. To respond to this request wit    7025 wants to read. To respond to this request with a successful read, userspace
7026 writes the respective data into the "data" fi    7026 writes the respective data into the "data" field and must continue guest
7027 execution to ensure the read data is transfer    7027 execution to ensure the read data is transferred into guest register state.
7028                                                  7028 
7029 If the RDMSR request was unsuccessful, usersp    7029 If the RDMSR request was unsuccessful, userspace indicates that with a "1" in
7030 the "error" field. This will inject a #GP int    7030 the "error" field. This will inject a #GP into the guest when the VCPU is
7031 executed again.                                  7031 executed again.
7032                                                  7032 
7033 For KVM_EXIT_X86_WRMSR, the "index" field tel    7033 For KVM_EXIT_X86_WRMSR, the "index" field tells userspace which MSR the guest
7034 wants to write. Once finished processing the     7034 wants to write. Once finished processing the event, userspace must continue
7035 vCPU execution. If the MSR write was unsucces    7035 vCPU execution. If the MSR write was unsuccessful, userspace also sets the
7036 "error" field to "1".                            7036 "error" field to "1".
7037                                                  7037 
7038 See KVM_X86_SET_MSR_FILTER for details on the    7038 See KVM_X86_SET_MSR_FILTER for details on the interaction with MSR filtering.
7039                                                  7039 
7040 ::                                               7040 ::
7041                                                  7041 
7042                                                  7042 
7043                 struct kvm_xen_exit {            7043                 struct kvm_xen_exit {
7044   #define KVM_EXIT_XEN_HCALL          1          7044   #define KVM_EXIT_XEN_HCALL          1
7045                         __u32 type;              7045                         __u32 type;
7046                         union {                  7046                         union {
7047                                 struct {         7047                                 struct {
7048                                         __u32    7048                                         __u32 longmode;
7049                                         __u32    7049                                         __u32 cpl;
7050                                         __u64    7050                                         __u64 input;
7051                                         __u64    7051                                         __u64 result;
7052                                         __u64    7052                                         __u64 params[6];
7053                                 } hcall;         7053                                 } hcall;
7054                         } u;                     7054                         } u;
7055                 };                               7055                 };
7056                 /* KVM_EXIT_XEN */               7056                 /* KVM_EXIT_XEN */
7057                 struct kvm_hyperv_exit xen;      7057                 struct kvm_hyperv_exit xen;
7058                                                  7058 
7059 Indicates that the VCPU exits into userspace     7059 Indicates that the VCPU exits into userspace to process some tasks
7060 related to Xen emulation.                        7060 related to Xen emulation.
7061                                                  7061 
7062 Valid values for 'type' are:                     7062 Valid values for 'type' are:
7063                                                  7063 
7064   - KVM_EXIT_XEN_HCALL -- synchronously notif    7064   - KVM_EXIT_XEN_HCALL -- synchronously notify user-space about Xen hypercall.
7065     Userspace is expected to place the hyperc    7065     Userspace is expected to place the hypercall result into the appropriate
7066     field before invoking KVM_RUN again.         7066     field before invoking KVM_RUN again.
7067                                                  7067 
7068 ::                                               7068 ::
7069                                                  7069 
7070                 /* KVM_EXIT_RISCV_SBI */         7070                 /* KVM_EXIT_RISCV_SBI */
7071                 struct {                         7071                 struct {
7072                         unsigned long extensi    7072                         unsigned long extension_id;
7073                         unsigned long functio    7073                         unsigned long function_id;
7074                         unsigned long args[6]    7074                         unsigned long args[6];
7075                         unsigned long ret[2];    7075                         unsigned long ret[2];
7076                 } riscv_sbi;                     7076                 } riscv_sbi;
7077                                                  7077 
7078 If exit reason is KVM_EXIT_RISCV_SBI then it     7078 If exit reason is KVM_EXIT_RISCV_SBI then it indicates that the VCPU has
7079 done a SBI call which is not handled by KVM R    7079 done a SBI call which is not handled by KVM RISC-V kernel module. The details
7080 of the SBI call are available in 'riscv_sbi'     7080 of the SBI call are available in 'riscv_sbi' member of kvm_run structure. The
7081 'extension_id' field of 'riscv_sbi' represent    7081 'extension_id' field of 'riscv_sbi' represents SBI extension ID whereas the
7082 'function_id' field represents function ID of    7082 'function_id' field represents function ID of given SBI extension. The 'args'
7083 array field of 'riscv_sbi' represents paramet    7083 array field of 'riscv_sbi' represents parameters for the SBI call and 'ret'
7084 array field represents return values. The use    7084 array field represents return values. The userspace should update the return
7085 values of SBI call before resuming the VCPU.     7085 values of SBI call before resuming the VCPU. For more details on RISC-V SBI
7086 spec refer, https://github.com/riscv/riscv-sb    7086 spec refer, https://github.com/riscv/riscv-sbi-doc.
7087                                                  7087 
7088 ::                                               7088 ::
7089                                                  7089 
7090                 /* KVM_EXIT_MEMORY_FAULT */      7090                 /* KVM_EXIT_MEMORY_FAULT */
7091                 struct {                         7091                 struct {
7092   #define KVM_MEMORY_EXIT_FLAG_PRIVATE  (1ULL    7092   #define KVM_MEMORY_EXIT_FLAG_PRIVATE  (1ULL << 3)
7093                         __u64 flags;             7093                         __u64 flags;
7094                         __u64 gpa;               7094                         __u64 gpa;
7095                         __u64 size;              7095                         __u64 size;
7096                 } memory_fault;                  7096                 } memory_fault;
7097                                                  7097 
7098 KVM_EXIT_MEMORY_FAULT indicates the vCPU has     7098 KVM_EXIT_MEMORY_FAULT indicates the vCPU has encountered a memory fault that
7099 could not be resolved by KVM.  The 'gpa' and     7099 could not be resolved by KVM.  The 'gpa' and 'size' (in bytes) describe the
7100 guest physical address range [gpa, gpa + size    7100 guest physical address range [gpa, gpa + size) of the fault.  The 'flags' field
7101 describes properties of the faulting access t    7101 describes properties of the faulting access that are likely pertinent:
7102                                                  7102 
7103  - KVM_MEMORY_EXIT_FLAG_PRIVATE - When set, i    7103  - KVM_MEMORY_EXIT_FLAG_PRIVATE - When set, indicates the memory fault occurred
7104    on a private memory access.  When clear, i    7104    on a private memory access.  When clear, indicates the fault occurred on a
7105    shared access.                                7105    shared access.
7106                                                  7106 
7107 Note!  KVM_EXIT_MEMORY_FAULT is unique among     7107 Note!  KVM_EXIT_MEMORY_FAULT is unique among all KVM exit reasons in that it
7108 accompanies a return code of '-1', not '0'!      7108 accompanies a return code of '-1', not '0'!  errno will always be set to EFAULT
7109 or EHWPOISON when KVM exits with KVM_EXIT_MEM    7109 or EHWPOISON when KVM exits with KVM_EXIT_MEMORY_FAULT, userspace should assume
7110 kvm_run.exit_reason is stale/undefined for al    7110 kvm_run.exit_reason is stale/undefined for all other error numbers.
7111                                                  7111 
7112 ::                                               7112 ::
7113                                                  7113 
7114     /* KVM_EXIT_NOTIFY */                        7114     /* KVM_EXIT_NOTIFY */
7115     struct {                                     7115     struct {
7116   #define KVM_NOTIFY_CONTEXT_INVALID    (1 <<    7116   #define KVM_NOTIFY_CONTEXT_INVALID    (1 << 0)
7117       __u32 flags;                               7117       __u32 flags;
7118     } notify;                                    7118     } notify;
7119                                                  7119 
7120 Used on x86 systems. When the VM capability K    7120 Used on x86 systems. When the VM capability KVM_CAP_X86_NOTIFY_VMEXIT is
7121 enabled, a VM exit generated if no event wind    7121 enabled, a VM exit generated if no event window occurs in VM non-root mode
7122 for a specified amount of time. Once KVM_X86_    7122 for a specified amount of time. Once KVM_X86_NOTIFY_VMEXIT_USER is set when
7123 enabling the cap, it would exit to userspace     7123 enabling the cap, it would exit to userspace with the exit reason
7124 KVM_EXIT_NOTIFY for further handling. The "fl    7124 KVM_EXIT_NOTIFY for further handling. The "flags" field contains more
7125 detailed info.                                   7125 detailed info.
7126                                                  7126 
7127 The valid value for 'flags' is:                  7127 The valid value for 'flags' is:
7128                                                  7128 
7129   - KVM_NOTIFY_CONTEXT_INVALID -- the VM cont    7129   - KVM_NOTIFY_CONTEXT_INVALID -- the VM context is corrupted and not valid
7130     in VMCS. It would run into unknown result    7130     in VMCS. It would run into unknown result if resume the target VM.
7131                                                  7131 
7132 ::                                               7132 ::
7133                                                  7133 
7134                 /* Fix the size of the union.    7134                 /* Fix the size of the union. */
7135                 char padding[256];               7135                 char padding[256];
7136         };                                       7136         };
7137                                                  7137 
7138         /*                                       7138         /*
7139          * shared registers between kvm and u    7139          * shared registers between kvm and userspace.
7140          * kvm_valid_regs specifies the regis    7140          * kvm_valid_regs specifies the register classes set by the host
7141          * kvm_dirty_regs specified the regis    7141          * kvm_dirty_regs specified the register classes dirtied by userspace
7142          * struct kvm_sync_regs is architectu    7142          * struct kvm_sync_regs is architecture specific, as well as the
7143          * bits for kvm_valid_regs and kvm_di    7143          * bits for kvm_valid_regs and kvm_dirty_regs
7144          */                                      7144          */
7145         __u64 kvm_valid_regs;                    7145         __u64 kvm_valid_regs;
7146         __u64 kvm_dirty_regs;                    7146         __u64 kvm_dirty_regs;
7147         union {                                  7147         union {
7148                 struct kvm_sync_regs regs;       7148                 struct kvm_sync_regs regs;
7149                 char padding[SYNC_REGS_SIZE_B    7149                 char padding[SYNC_REGS_SIZE_BYTES];
7150         } s;                                     7150         } s;
7151                                                  7151 
7152 If KVM_CAP_SYNC_REGS is defined, these fields    7152 If KVM_CAP_SYNC_REGS is defined, these fields allow userspace to access
7153 certain guest registers without having to cal    7153 certain guest registers without having to call SET/GET_*REGS. Thus we can
7154 avoid some system call overhead if userspace     7154 avoid some system call overhead if userspace has to handle the exit.
7155 Userspace can query the validity of the struc    7155 Userspace can query the validity of the structure by checking
7156 kvm_valid_regs for specific bits. These bits     7156 kvm_valid_regs for specific bits. These bits are architecture specific
7157 and usually define the validity of a groups o    7157 and usually define the validity of a groups of registers. (e.g. one bit
7158 for general purpose registers)                   7158 for general purpose registers)
7159                                                  7159 
7160 Please note that the kernel is allowed to use    7160 Please note that the kernel is allowed to use the kvm_run structure as the
7161 primary storage for certain register types. T    7161 primary storage for certain register types. Therefore, the kernel may use the
7162 values in kvm_run even if the corresponding b    7162 values in kvm_run even if the corresponding bit in kvm_dirty_regs is not set.
7163                                                  7163 
7164                                                  7164 
7165 6. Capabilities that can be enabled on vCPUs     7165 6. Capabilities that can be enabled on vCPUs
7166 ============================================     7166 ============================================
7167                                                  7167 
7168 There are certain capabilities that change th    7168 There are certain capabilities that change the behavior of the virtual CPU or
7169 the virtual machine when enabled. To enable t    7169 the virtual machine when enabled. To enable them, please see section 4.37.
7170 Below you can find a list of capabilities and    7170 Below you can find a list of capabilities and what their effect on the vCPU or
7171 the virtual machine is when enabling them.       7171 the virtual machine is when enabling them.
7172                                                  7172 
7173 The following information is provided along w    7173 The following information is provided along with the description:
7174                                                  7174 
7175   Architectures:                                 7175   Architectures:
7176       which instruction set architectures pro    7176       which instruction set architectures provide this ioctl.
7177       x86 includes both i386 and x86_64.         7177       x86 includes both i386 and x86_64.
7178                                                  7178 
7179   Target:                                        7179   Target:
7180       whether this is a per-vcpu or per-vm ca    7180       whether this is a per-vcpu or per-vm capability.
7181                                                  7181 
7182   Parameters:                                    7182   Parameters:
7183       what parameters are accepted by the cap    7183       what parameters are accepted by the capability.
7184                                                  7184 
7185   Returns:                                       7185   Returns:
7186       the return value.  General error number    7186       the return value.  General error numbers (EBADF, ENOMEM, EINVAL)
7187       are not detailed, but errors with speci    7187       are not detailed, but errors with specific meanings are.
7188                                                  7188 
7189                                                  7189 
7190 6.1 KVM_CAP_PPC_OSI                              7190 6.1 KVM_CAP_PPC_OSI
7191 -------------------                              7191 -------------------
7192                                                  7192 
7193 :Architectures: ppc                              7193 :Architectures: ppc
7194 :Target: vcpu                                    7194 :Target: vcpu
7195 :Parameters: none                                7195 :Parameters: none
7196 :Returns: 0 on success; -1 on error              7196 :Returns: 0 on success; -1 on error
7197                                                  7197 
7198 This capability enables interception of OSI h    7198 This capability enables interception of OSI hypercalls that otherwise would
7199 be treated as normal system calls to be injec    7199 be treated as normal system calls to be injected into the guest. OSI hypercalls
7200 were invented by Mac-on-Linux to have a stand    7200 were invented by Mac-on-Linux to have a standardized communication mechanism
7201 between the guest and the host.                  7201 between the guest and the host.
7202                                                  7202 
7203 When this capability is enabled, KVM_EXIT_OSI    7203 When this capability is enabled, KVM_EXIT_OSI can occur.
7204                                                  7204 
7205                                                  7205 
7206 6.2 KVM_CAP_PPC_PAPR                             7206 6.2 KVM_CAP_PPC_PAPR
7207 --------------------                             7207 --------------------
7208                                                  7208 
7209 :Architectures: ppc                              7209 :Architectures: ppc
7210 :Target: vcpu                                    7210 :Target: vcpu
7211 :Parameters: none                                7211 :Parameters: none
7212 :Returns: 0 on success; -1 on error              7212 :Returns: 0 on success; -1 on error
7213                                                  7213 
7214 This capability enables interception of PAPR     7214 This capability enables interception of PAPR hypercalls. PAPR hypercalls are
7215 done using the hypercall instruction "sc 1".     7215 done using the hypercall instruction "sc 1".
7216                                                  7216 
7217 It also sets the guest privilege level to "su    7217 It also sets the guest privilege level to "supervisor" mode. Usually the guest
7218 runs in "hypervisor" privilege mode with a fe    7218 runs in "hypervisor" privilege mode with a few missing features.
7219                                                  7219 
7220 In addition to the above, it changes the sema    7220 In addition to the above, it changes the semantics of SDR1. In this mode, the
7221 HTAB address part of SDR1 contains an HVA ins    7221 HTAB address part of SDR1 contains an HVA instead of a GPA, as PAPR keeps the
7222 HTAB invisible to the guest.                     7222 HTAB invisible to the guest.
7223                                                  7223 
7224 When this capability is enabled, KVM_EXIT_PAP    7224 When this capability is enabled, KVM_EXIT_PAPR_HCALL can occur.
7225                                                  7225 
7226                                                  7226 
7227 6.3 KVM_CAP_SW_TLB                               7227 6.3 KVM_CAP_SW_TLB
7228 ------------------                               7228 ------------------
7229                                                  7229 
7230 :Architectures: ppc                              7230 :Architectures: ppc
7231 :Target: vcpu                                    7231 :Target: vcpu
7232 :Parameters: args[0] is the address of a stru    7232 :Parameters: args[0] is the address of a struct kvm_config_tlb
7233 :Returns: 0 on success; -1 on error              7233 :Returns: 0 on success; -1 on error
7234                                                  7234 
7235 ::                                               7235 ::
7236                                                  7236 
7237   struct kvm_config_tlb {                        7237   struct kvm_config_tlb {
7238         __u64 params;                            7238         __u64 params;
7239         __u64 array;                             7239         __u64 array;
7240         __u32 mmu_type;                          7240         __u32 mmu_type;
7241         __u32 array_len;                         7241         __u32 array_len;
7242   };                                             7242   };
7243                                                  7243 
7244 Configures the virtual CPU's TLB array, estab    7244 Configures the virtual CPU's TLB array, establishing a shared memory area
7245 between userspace and KVM.  The "params" and     7245 between userspace and KVM.  The "params" and "array" fields are userspace
7246 addresses of mmu-type-specific data structure    7246 addresses of mmu-type-specific data structures.  The "array_len" field is an
7247 safety mechanism, and should be set to the si    7247 safety mechanism, and should be set to the size in bytes of the memory that
7248 userspace has reserved for the array.  It mus    7248 userspace has reserved for the array.  It must be at least the size dictated
7249 by "mmu_type" and "params".                      7249 by "mmu_type" and "params".
7250                                                  7250 
7251 While KVM_RUN is active, the shared region is    7251 While KVM_RUN is active, the shared region is under control of KVM.  Its
7252 contents are undefined, and any modification     7252 contents are undefined, and any modification by userspace results in
7253 boundedly undefined behavior.                    7253 boundedly undefined behavior.
7254                                                  7254 
7255 On return from KVM_RUN, the shared region wil    7255 On return from KVM_RUN, the shared region will reflect the current state of
7256 the guest's TLB.  If userspace makes any chan    7256 the guest's TLB.  If userspace makes any changes, it must call KVM_DIRTY_TLB
7257 to tell KVM which entries have been changed,     7257 to tell KVM which entries have been changed, prior to calling KVM_RUN again
7258 on this vcpu.                                    7258 on this vcpu.
7259                                                  7259 
7260 For mmu types KVM_MMU_FSL_BOOKE_NOHV and KVM_    7260 For mmu types KVM_MMU_FSL_BOOKE_NOHV and KVM_MMU_FSL_BOOKE_HV:
7261                                                  7261 
7262  - The "params" field is of type "struct kvm_    7262  - The "params" field is of type "struct kvm_book3e_206_tlb_params".
7263  - The "array" field points to an array of ty    7263  - The "array" field points to an array of type "struct
7264    kvm_book3e_206_tlb_entry".                    7264    kvm_book3e_206_tlb_entry".
7265  - The array consists of all entries in the f    7265  - The array consists of all entries in the first TLB, followed by all
7266    entries in the second TLB.                    7266    entries in the second TLB.
7267  - Within a TLB, entries are ordered first by    7267  - Within a TLB, entries are ordered first by increasing set number.  Within a
7268    set, entries are ordered by way (increasin    7268    set, entries are ordered by way (increasing ESEL).
7269  - The hash for determining set number in TLB    7269  - The hash for determining set number in TLB0 is: (MAS2 >> 12) & (num_sets - 1)
7270    where "num_sets" is the tlb_sizes[] value     7270    where "num_sets" is the tlb_sizes[] value divided by the tlb_ways[] value.
7271  - The tsize field of mas1 shall be set to 4K    7271  - The tsize field of mas1 shall be set to 4K on TLB0, even though the
7272    hardware ignores this value for TLB0.         7272    hardware ignores this value for TLB0.
7273                                                  7273 
7274 6.4 KVM_CAP_S390_CSS_SUPPORT                     7274 6.4 KVM_CAP_S390_CSS_SUPPORT
7275 ----------------------------                     7275 ----------------------------
7276                                                  7276 
7277 :Architectures: s390                             7277 :Architectures: s390
7278 :Target: vcpu                                    7278 :Target: vcpu
7279 :Parameters: none                                7279 :Parameters: none
7280 :Returns: 0 on success; -1 on error              7280 :Returns: 0 on success; -1 on error
7281                                                  7281 
7282 This capability enables support for handling     7282 This capability enables support for handling of channel I/O instructions.
7283                                                  7283 
7284 TEST PENDING INTERRUPTION and the interrupt p    7284 TEST PENDING INTERRUPTION and the interrupt portion of TEST SUBCHANNEL are
7285 handled in-kernel, while the other I/O instru    7285 handled in-kernel, while the other I/O instructions are passed to userspace.
7286                                                  7286 
7287 When this capability is enabled, KVM_EXIT_S39    7287 When this capability is enabled, KVM_EXIT_S390_TSCH will occur on TEST
7288 SUBCHANNEL intercepts.                           7288 SUBCHANNEL intercepts.
7289                                                  7289 
7290 Note that even though this capability is enab    7290 Note that even though this capability is enabled per-vcpu, the complete
7291 virtual machine is affected.                     7291 virtual machine is affected.
7292                                                  7292 
7293 6.5 KVM_CAP_PPC_EPR                              7293 6.5 KVM_CAP_PPC_EPR
7294 -------------------                              7294 -------------------
7295                                                  7295 
7296 :Architectures: ppc                              7296 :Architectures: ppc
7297 :Target: vcpu                                    7297 :Target: vcpu
7298 :Parameters: args[0] defines whether the prox    7298 :Parameters: args[0] defines whether the proxy facility is active
7299 :Returns: 0 on success; -1 on error              7299 :Returns: 0 on success; -1 on error
7300                                                  7300 
7301 This capability enables or disables the deliv    7301 This capability enables or disables the delivery of interrupts through the
7302 external proxy facility.                         7302 external proxy facility.
7303                                                  7303 
7304 When enabled (args[0] != 0), every time the g    7304 When enabled (args[0] != 0), every time the guest gets an external interrupt
7305 delivered, it automatically exits into user s    7305 delivered, it automatically exits into user space with a KVM_EXIT_EPR exit
7306 to receive the topmost interrupt vector.         7306 to receive the topmost interrupt vector.
7307                                                  7307 
7308 When disabled (args[0] == 0), behavior is as     7308 When disabled (args[0] == 0), behavior is as if this facility is unsupported.
7309                                                  7309 
7310 When this capability is enabled, KVM_EXIT_EPR    7310 When this capability is enabled, KVM_EXIT_EPR can occur.
7311                                                  7311 
7312 6.6 KVM_CAP_IRQ_MPIC                             7312 6.6 KVM_CAP_IRQ_MPIC
7313 --------------------                             7313 --------------------
7314                                                  7314 
7315 :Architectures: ppc                              7315 :Architectures: ppc
7316 :Parameters: args[0] is the MPIC device fd;      7316 :Parameters: args[0] is the MPIC device fd;
7317              args[1] is the MPIC CPU number f    7317              args[1] is the MPIC CPU number for this vcpu
7318                                                  7318 
7319 This capability connects the vcpu to an in-ke    7319 This capability connects the vcpu to an in-kernel MPIC device.
7320                                                  7320 
7321 6.7 KVM_CAP_IRQ_XICS                             7321 6.7 KVM_CAP_IRQ_XICS
7322 --------------------                             7322 --------------------
7323                                                  7323 
7324 :Architectures: ppc                              7324 :Architectures: ppc
7325 :Target: vcpu                                    7325 :Target: vcpu
7326 :Parameters: args[0] is the XICS device fd;      7326 :Parameters: args[0] is the XICS device fd;
7327              args[1] is the XICS CPU number (    7327              args[1] is the XICS CPU number (server ID) for this vcpu
7328                                                  7328 
7329 This capability connects the vcpu to an in-ke    7329 This capability connects the vcpu to an in-kernel XICS device.
7330                                                  7330 
7331 6.8 KVM_CAP_S390_IRQCHIP                         7331 6.8 KVM_CAP_S390_IRQCHIP
7332 ------------------------                         7332 ------------------------
7333                                                  7333 
7334 :Architectures: s390                             7334 :Architectures: s390
7335 :Target: vm                                      7335 :Target: vm
7336 :Parameters: none                                7336 :Parameters: none
7337                                                  7337 
7338 This capability enables the in-kernel irqchip    7338 This capability enables the in-kernel irqchip for s390. Please refer to
7339 "4.24 KVM_CREATE_IRQCHIP" for details.           7339 "4.24 KVM_CREATE_IRQCHIP" for details.
7340                                                  7340 
7341 6.9 KVM_CAP_MIPS_FPU                             7341 6.9 KVM_CAP_MIPS_FPU
7342 --------------------                             7342 --------------------
7343                                                  7343 
7344 :Architectures: mips                             7344 :Architectures: mips
7345 :Target: vcpu                                    7345 :Target: vcpu
7346 :Parameters: args[0] is reserved for future u    7346 :Parameters: args[0] is reserved for future use (should be 0).
7347                                                  7347 
7348 This capability allows the use of the host Fl    7348 This capability allows the use of the host Floating Point Unit by the guest. It
7349 allows the Config1.FP bit to be set to enable    7349 allows the Config1.FP bit to be set to enable the FPU in the guest. Once this is
7350 done the ``KVM_REG_MIPS_FPR_*`` and ``KVM_REG    7350 done the ``KVM_REG_MIPS_FPR_*`` and ``KVM_REG_MIPS_FCR_*`` registers can be
7351 accessed (depending on the current guest FPU     7351 accessed (depending on the current guest FPU register mode), and the Status.FR,
7352 Config5.FRE bits are accessible via the KVM A    7352 Config5.FRE bits are accessible via the KVM API and also from the guest,
7353 depending on them being supported by the FPU.    7353 depending on them being supported by the FPU.
7354                                                  7354 
7355 6.10 KVM_CAP_MIPS_MSA                            7355 6.10 KVM_CAP_MIPS_MSA
7356 ---------------------                            7356 ---------------------
7357                                                  7357 
7358 :Architectures: mips                             7358 :Architectures: mips
7359 :Target: vcpu                                    7359 :Target: vcpu
7360 :Parameters: args[0] is reserved for future u    7360 :Parameters: args[0] is reserved for future use (should be 0).
7361                                                  7361 
7362 This capability allows the use of the MIPS SI    7362 This capability allows the use of the MIPS SIMD Architecture (MSA) by the guest.
7363 It allows the Config3.MSAP bit to be set to e    7363 It allows the Config3.MSAP bit to be set to enable the use of MSA by the guest.
7364 Once this is done the ``KVM_REG_MIPS_VEC_*``     7364 Once this is done the ``KVM_REG_MIPS_VEC_*`` and ``KVM_REG_MIPS_MSA_*``
7365 registers can be accessed, and the Config5.MS    7365 registers can be accessed, and the Config5.MSAEn bit is accessible via the
7366 KVM API and also from the guest.                 7366 KVM API and also from the guest.
7367                                                  7367 
7368 6.74 KVM_CAP_SYNC_REGS                           7368 6.74 KVM_CAP_SYNC_REGS
7369 ----------------------                           7369 ----------------------
7370                                                  7370 
7371 :Architectures: s390, x86                        7371 :Architectures: s390, x86
7372 :Target: s390: always enabled, x86: vcpu         7372 :Target: s390: always enabled, x86: vcpu
7373 :Parameters: none                                7373 :Parameters: none
7374 :Returns: x86: KVM_CHECK_EXTENSION returns a     7374 :Returns: x86: KVM_CHECK_EXTENSION returns a bit-array indicating which register
7375           sets are supported                     7375           sets are supported
7376           (bitfields defined in arch/x86/incl    7376           (bitfields defined in arch/x86/include/uapi/asm/kvm.h).
7377                                                  7377 
7378 As described above in the kvm_sync_regs struc    7378 As described above in the kvm_sync_regs struct info in section 5 (kvm_run):
7379 KVM_CAP_SYNC_REGS "allow[s] userspace to acce    7379 KVM_CAP_SYNC_REGS "allow[s] userspace to access certain guest registers
7380 without having to call SET/GET_*REGS". This r    7380 without having to call SET/GET_*REGS". This reduces overhead by eliminating
7381 repeated ioctl calls for setting and/or getti    7381 repeated ioctl calls for setting and/or getting register values. This is
7382 particularly important when userspace is maki    7382 particularly important when userspace is making synchronous guest state
7383 modifications, e.g. when emulating and/or int    7383 modifications, e.g. when emulating and/or intercepting instructions in
7384 userspace.                                       7384 userspace.
7385                                                  7385 
7386 For s390 specifics, please refer to the sourc    7386 For s390 specifics, please refer to the source code.
7387                                                  7387 
7388 For x86:                                         7388 For x86:
7389                                                  7389 
7390 - the register sets to be copied out to kvm_r    7390 - the register sets to be copied out to kvm_run are selectable
7391   by userspace (rather that all sets being co    7391   by userspace (rather that all sets being copied out for every exit).
7392 - vcpu_events are available in addition to re    7392 - vcpu_events are available in addition to regs and sregs.
7393                                                  7393 
7394 For x86, the 'kvm_valid_regs' field of struct    7394 For x86, the 'kvm_valid_regs' field of struct kvm_run is overloaded to
7395 function as an input bit-array field set by u    7395 function as an input bit-array field set by userspace to indicate the
7396 specific register sets to be copied out on th    7396 specific register sets to be copied out on the next exit.
7397                                                  7397 
7398 To indicate when userspace has modified value    7398 To indicate when userspace has modified values that should be copied into
7399 the vCPU, the all architecture bitarray field    7399 the vCPU, the all architecture bitarray field, 'kvm_dirty_regs' must be set.
7400 This is done using the same bitflags as for t    7400 This is done using the same bitflags as for the 'kvm_valid_regs' field.
7401 If the dirty bit is not set, then the registe    7401 If the dirty bit is not set, then the register set values will not be copied
7402 into the vCPU even if they've been modified.     7402 into the vCPU even if they've been modified.
7403                                                  7403 
7404 Unused bitfields in the bitarrays must be set    7404 Unused bitfields in the bitarrays must be set to zero.
7405                                                  7405 
7406 ::                                               7406 ::
7407                                                  7407 
7408   struct kvm_sync_regs {                         7408   struct kvm_sync_regs {
7409         struct kvm_regs regs;                    7409         struct kvm_regs regs;
7410         struct kvm_sregs sregs;                  7410         struct kvm_sregs sregs;
7411         struct kvm_vcpu_events events;           7411         struct kvm_vcpu_events events;
7412   };                                             7412   };
7413                                                  7413 
7414 6.75 KVM_CAP_PPC_IRQ_XIVE                        7414 6.75 KVM_CAP_PPC_IRQ_XIVE
7415 -------------------------                        7415 -------------------------
7416                                                  7416 
7417 :Architectures: ppc                              7417 :Architectures: ppc
7418 :Target: vcpu                                    7418 :Target: vcpu
7419 :Parameters: args[0] is the XIVE device fd;      7419 :Parameters: args[0] is the XIVE device fd;
7420              args[1] is the XIVE CPU number (    7420              args[1] is the XIVE CPU number (server ID) for this vcpu
7421                                                  7421 
7422 This capability connects the vcpu to an in-ke    7422 This capability connects the vcpu to an in-kernel XIVE device.
7423                                                  7423 
7424 7. Capabilities that can be enabled on VMs       7424 7. Capabilities that can be enabled on VMs
7425 ==========================================       7425 ==========================================
7426                                                  7426 
7427 There are certain capabilities that change th    7427 There are certain capabilities that change the behavior of the virtual
7428 machine when enabled. To enable them, please     7428 machine when enabled. To enable them, please see section 4.37. Below
7429 you can find a list of capabilities and what     7429 you can find a list of capabilities and what their effect on the VM
7430 is when enabling them.                           7430 is when enabling them.
7431                                                  7431 
7432 The following information is provided along w    7432 The following information is provided along with the description:
7433                                                  7433 
7434   Architectures:                                 7434   Architectures:
7435       which instruction set architectures pro    7435       which instruction set architectures provide this ioctl.
7436       x86 includes both i386 and x86_64.         7436       x86 includes both i386 and x86_64.
7437                                                  7437 
7438   Parameters:                                    7438   Parameters:
7439       what parameters are accepted by the cap    7439       what parameters are accepted by the capability.
7440                                                  7440 
7441   Returns:                                       7441   Returns:
7442       the return value.  General error number    7442       the return value.  General error numbers (EBADF, ENOMEM, EINVAL)
7443       are not detailed, but errors with speci    7443       are not detailed, but errors with specific meanings are.
7444                                                  7444 
7445                                                  7445 
7446 7.1 KVM_CAP_PPC_ENABLE_HCALL                     7446 7.1 KVM_CAP_PPC_ENABLE_HCALL
7447 ----------------------------                     7447 ----------------------------
7448                                                  7448 
7449 :Architectures: ppc                              7449 :Architectures: ppc
7450 :Parameters: args[0] is the sPAPR hcall numbe    7450 :Parameters: args[0] is the sPAPR hcall number;
7451              args[1] is 0 to disable, 1 to en    7451              args[1] is 0 to disable, 1 to enable in-kernel handling
7452                                                  7452 
7453 This capability controls whether individual s    7453 This capability controls whether individual sPAPR hypercalls (hcalls)
7454 get handled by the kernel or not.  Enabling o    7454 get handled by the kernel or not.  Enabling or disabling in-kernel
7455 handling of an hcall is effective across the     7455 handling of an hcall is effective across the VM.  On creation, an
7456 initial set of hcalls are enabled for in-kern    7456 initial set of hcalls are enabled for in-kernel handling, which
7457 consists of those hcalls for which in-kernel     7457 consists of those hcalls for which in-kernel handlers were implemented
7458 before this capability was implemented.  If d    7458 before this capability was implemented.  If disabled, the kernel will
7459 not to attempt to handle the hcall, but will     7459 not to attempt to handle the hcall, but will always exit to userspace
7460 to handle it.  Note that it may not make sens    7460 to handle it.  Note that it may not make sense to enable some and
7461 disable others of a group of related hcalls,     7461 disable others of a group of related hcalls, but KVM does not prevent
7462 userspace from doing that.                       7462 userspace from doing that.
7463                                                  7463 
7464 If the hcall number specified is not one that    7464 If the hcall number specified is not one that has an in-kernel
7465 implementation, the KVM_ENABLE_CAP ioctl will    7465 implementation, the KVM_ENABLE_CAP ioctl will fail with an EINVAL
7466 error.                                           7466 error.
7467                                                  7467 
7468 7.2 KVM_CAP_S390_USER_SIGP                       7468 7.2 KVM_CAP_S390_USER_SIGP
7469 --------------------------                       7469 --------------------------
7470                                                  7470 
7471 :Architectures: s390                             7471 :Architectures: s390
7472 :Parameters: none                                7472 :Parameters: none
7473                                                  7473 
7474 This capability controls which SIGP orders wi    7474 This capability controls which SIGP orders will be handled completely in user
7475 space. With this capability enabled, all fast    7475 space. With this capability enabled, all fast orders will be handled completely
7476 in the kernel:                                   7476 in the kernel:
7477                                                  7477 
7478 - SENSE                                          7478 - SENSE
7479 - SENSE RUNNING                                  7479 - SENSE RUNNING
7480 - EXTERNAL CALL                                  7480 - EXTERNAL CALL
7481 - EMERGENCY SIGNAL                               7481 - EMERGENCY SIGNAL
7482 - CONDITIONAL EMERGENCY SIGNAL                   7482 - CONDITIONAL EMERGENCY SIGNAL
7483                                                  7483 
7484 All other orders will be handled completely i    7484 All other orders will be handled completely in user space.
7485                                                  7485 
7486 Only privileged operation exceptions will be     7486 Only privileged operation exceptions will be checked for in the kernel (or even
7487 in the hardware prior to interception). If th    7487 in the hardware prior to interception). If this capability is not enabled, the
7488 old way of handling SIGP orders is used (part    7488 old way of handling SIGP orders is used (partially in kernel and user space).
7489                                                  7489 
7490 7.3 KVM_CAP_S390_VECTOR_REGISTERS                7490 7.3 KVM_CAP_S390_VECTOR_REGISTERS
7491 ---------------------------------                7491 ---------------------------------
7492                                                  7492 
7493 :Architectures: s390                             7493 :Architectures: s390
7494 :Parameters: none                                7494 :Parameters: none
7495 :Returns: 0 on success, negative value on err    7495 :Returns: 0 on success, negative value on error
7496                                                  7496 
7497 Allows use of the vector registers introduced    7497 Allows use of the vector registers introduced with z13 processor, and
7498 provides for the synchronization between host    7498 provides for the synchronization between host and user space.  Will
7499 return -EINVAL if the machine does not suppor    7499 return -EINVAL if the machine does not support vectors.
7500                                                  7500 
7501 7.4 KVM_CAP_S390_USER_STSI                       7501 7.4 KVM_CAP_S390_USER_STSI
7502 --------------------------                       7502 --------------------------
7503                                                  7503 
7504 :Architectures: s390                             7504 :Architectures: s390
7505 :Parameters: none                                7505 :Parameters: none
7506                                                  7506 
7507 This capability allows post-handlers for the     7507 This capability allows post-handlers for the STSI instruction. After
7508 initial handling in the kernel, KVM exits to     7508 initial handling in the kernel, KVM exits to user space with
7509 KVM_EXIT_S390_STSI to allow user space to ins    7509 KVM_EXIT_S390_STSI to allow user space to insert further data.
7510                                                  7510 
7511 Before exiting to userspace, kvm handlers sho    7511 Before exiting to userspace, kvm handlers should fill in s390_stsi field of
7512 vcpu->run::                                      7512 vcpu->run::
7513                                                  7513 
7514   struct {                                       7514   struct {
7515         __u64 addr;                              7515         __u64 addr;
7516         __u8 ar;                                 7516         __u8 ar;
7517         __u8 reserved;                           7517         __u8 reserved;
7518         __u8 fc;                                 7518         __u8 fc;
7519         __u8 sel1;                               7519         __u8 sel1;
7520         __u16 sel2;                              7520         __u16 sel2;
7521   } s390_stsi;                                   7521   } s390_stsi;
7522                                                  7522 
7523   @addr - guest address of STSI SYSIB            7523   @addr - guest address of STSI SYSIB
7524   @fc   - function code                          7524   @fc   - function code
7525   @sel1 - selector 1                             7525   @sel1 - selector 1
7526   @sel2 - selector 2                             7526   @sel2 - selector 2
7527   @ar   - access register number                 7527   @ar   - access register number
7528                                                  7528 
7529 KVM handlers should exit to userspace with rc    7529 KVM handlers should exit to userspace with rc = -EREMOTE.
7530                                                  7530 
7531 7.5 KVM_CAP_SPLIT_IRQCHIP                        7531 7.5 KVM_CAP_SPLIT_IRQCHIP
7532 -------------------------                        7532 -------------------------
7533                                                  7533 
7534 :Architectures: x86                              7534 :Architectures: x86
7535 :Parameters: args[0] - number of routes reser    7535 :Parameters: args[0] - number of routes reserved for userspace IOAPICs
7536 :Returns: 0 on success, -1 on error              7536 :Returns: 0 on success, -1 on error
7537                                                  7537 
7538 Create a local apic for each processor in the    7538 Create a local apic for each processor in the kernel. This can be used
7539 instead of KVM_CREATE_IRQCHIP if the userspac    7539 instead of KVM_CREATE_IRQCHIP if the userspace VMM wishes to emulate the
7540 IOAPIC and PIC (and also the PIT, even though    7540 IOAPIC and PIC (and also the PIT, even though this has to be enabled
7541 separately).                                     7541 separately).
7542                                                  7542 
7543 This capability also enables in kernel routin    7543 This capability also enables in kernel routing of interrupt requests;
7544 when KVM_CAP_SPLIT_IRQCHIP only routes of KVM    7544 when KVM_CAP_SPLIT_IRQCHIP only routes of KVM_IRQ_ROUTING_MSI type are
7545 used in the IRQ routing table.  The first arg    7545 used in the IRQ routing table.  The first args[0] MSI routes are reserved
7546 for the IOAPIC pins.  Whenever the LAPIC rece    7546 for the IOAPIC pins.  Whenever the LAPIC receives an EOI for these routes,
7547 a KVM_EXIT_IOAPIC_EOI vmexit will be reported    7547 a KVM_EXIT_IOAPIC_EOI vmexit will be reported to userspace.
7548                                                  7548 
7549 Fails if VCPU has already been created, or if    7549 Fails if VCPU has already been created, or if the irqchip is already in the
7550 kernel (i.e. KVM_CREATE_IRQCHIP has already b    7550 kernel (i.e. KVM_CREATE_IRQCHIP has already been called).
7551                                                  7551 
7552 7.6 KVM_CAP_S390_RI                              7552 7.6 KVM_CAP_S390_RI
7553 -------------------                              7553 -------------------
7554                                                  7554 
7555 :Architectures: s390                             7555 :Architectures: s390
7556 :Parameters: none                                7556 :Parameters: none
7557                                                  7557 
7558 Allows use of runtime-instrumentation introdu    7558 Allows use of runtime-instrumentation introduced with zEC12 processor.
7559 Will return -EINVAL if the machine does not s    7559 Will return -EINVAL if the machine does not support runtime-instrumentation.
7560 Will return -EBUSY if a VCPU has already been    7560 Will return -EBUSY if a VCPU has already been created.
7561                                                  7561 
7562 7.7 KVM_CAP_X2APIC_API                           7562 7.7 KVM_CAP_X2APIC_API
7563 ----------------------                           7563 ----------------------
7564                                                  7564 
7565 :Architectures: x86                              7565 :Architectures: x86
7566 :Parameters: args[0] - features that should b    7566 :Parameters: args[0] - features that should be enabled
7567 :Returns: 0 on success, -EINVAL when args[0]     7567 :Returns: 0 on success, -EINVAL when args[0] contains invalid features
7568                                                  7568 
7569 Valid feature flags in args[0] are::             7569 Valid feature flags in args[0] are::
7570                                                  7570 
7571   #define KVM_X2APIC_API_USE_32BIT_IDS           7571   #define KVM_X2APIC_API_USE_32BIT_IDS            (1ULL << 0)
7572   #define KVM_X2APIC_API_DISABLE_BROADCAST_QU    7572   #define KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK  (1ULL << 1)
7573                                                  7573 
7574 Enabling KVM_X2APIC_API_USE_32BIT_IDS changes    7574 Enabling KVM_X2APIC_API_USE_32BIT_IDS changes the behavior of
7575 KVM_SET_GSI_ROUTING, KVM_SIGNAL_MSI, KVM_SET_    7575 KVM_SET_GSI_ROUTING, KVM_SIGNAL_MSI, KVM_SET_LAPIC, and KVM_GET_LAPIC,
7576 allowing the use of 32-bit APIC IDs.  See KVM    7576 allowing the use of 32-bit APIC IDs.  See KVM_CAP_X2APIC_API in their
7577 respective sections.                             7577 respective sections.
7578                                                  7578 
7579 KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK must b    7579 KVM_X2APIC_API_DISABLE_BROADCAST_QUIRK must be enabled for x2APIC to work
7580 in logical mode or with more than 255 VCPUs.     7580 in logical mode or with more than 255 VCPUs.  Otherwise, KVM treats 0xff
7581 as a broadcast even in x2APIC mode in order t    7581 as a broadcast even in x2APIC mode in order to support physical x2APIC
7582 without interrupt remapping.  This is undesir    7582 without interrupt remapping.  This is undesirable in logical mode,
7583 where 0xff represents CPUs 0-7 in cluster 0.     7583 where 0xff represents CPUs 0-7 in cluster 0.
7584                                                  7584 
7585 7.8 KVM_CAP_S390_USER_INSTR0                     7585 7.8 KVM_CAP_S390_USER_INSTR0
7586 ----------------------------                     7586 ----------------------------
7587                                                  7587 
7588 :Architectures: s390                             7588 :Architectures: s390
7589 :Parameters: none                                7589 :Parameters: none
7590                                                  7590 
7591 With this capability enabled, all illegal ins    7591 With this capability enabled, all illegal instructions 0x0000 (2 bytes) will
7592 be intercepted and forwarded to user space. U    7592 be intercepted and forwarded to user space. User space can use this
7593 mechanism e.g. to realize 2-byte software bre    7593 mechanism e.g. to realize 2-byte software breakpoints. The kernel will
7594 not inject an operating exception for these i    7594 not inject an operating exception for these instructions, user space has
7595 to take care of that.                            7595 to take care of that.
7596                                                  7596 
7597 This capability can be enabled dynamically ev    7597 This capability can be enabled dynamically even if VCPUs were already
7598 created and are running.                         7598 created and are running.
7599                                                  7599 
7600 7.9 KVM_CAP_S390_GS                              7600 7.9 KVM_CAP_S390_GS
7601 -------------------                              7601 -------------------
7602                                                  7602 
7603 :Architectures: s390                             7603 :Architectures: s390
7604 :Parameters: none                                7604 :Parameters: none
7605 :Returns: 0 on success; -EINVAL if the machin    7605 :Returns: 0 on success; -EINVAL if the machine does not support
7606           guarded storage; -EBUSY if a VCPU h    7606           guarded storage; -EBUSY if a VCPU has already been created.
7607                                                  7607 
7608 Allows use of guarded storage for the KVM gue    7608 Allows use of guarded storage for the KVM guest.
7609                                                  7609 
7610 7.10 KVM_CAP_S390_AIS                            7610 7.10 KVM_CAP_S390_AIS
7611 ---------------------                            7611 ---------------------
7612                                                  7612 
7613 :Architectures: s390                             7613 :Architectures: s390
7614 :Parameters: none                                7614 :Parameters: none
7615                                                  7615 
7616 Allow use of adapter-interruption suppression    7616 Allow use of adapter-interruption suppression.
7617 :Returns: 0 on success; -EBUSY if a VCPU has     7617 :Returns: 0 on success; -EBUSY if a VCPU has already been created.
7618                                                  7618 
7619 7.11 KVM_CAP_PPC_SMT                             7619 7.11 KVM_CAP_PPC_SMT
7620 --------------------                             7620 --------------------
7621                                                  7621 
7622 :Architectures: ppc                              7622 :Architectures: ppc
7623 :Parameters: vsmt_mode, flags                    7623 :Parameters: vsmt_mode, flags
7624                                                  7624 
7625 Enabling this capability on a VM provides use    7625 Enabling this capability on a VM provides userspace with a way to set
7626 the desired virtual SMT mode (i.e. the number    7626 the desired virtual SMT mode (i.e. the number of virtual CPUs per
7627 virtual core).  The virtual SMT mode, vsmt_mo    7627 virtual core).  The virtual SMT mode, vsmt_mode, must be a power of 2
7628 between 1 and 8.  On POWER8, vsmt_mode must a    7628 between 1 and 8.  On POWER8, vsmt_mode must also be no greater than
7629 the number of threads per subcore for the hos    7629 the number of threads per subcore for the host.  Currently flags must
7630 be 0.  A successful call to enable this capab    7630 be 0.  A successful call to enable this capability will result in
7631 vsmt_mode being returned when the KVM_CAP_PPC    7631 vsmt_mode being returned when the KVM_CAP_PPC_SMT capability is
7632 subsequently queried for the VM.  This capabi    7632 subsequently queried for the VM.  This capability is only supported by
7633 HV KVM, and can only be set before any VCPUs     7633 HV KVM, and can only be set before any VCPUs have been created.
7634 The KVM_CAP_PPC_SMT_POSSIBLE capability indic    7634 The KVM_CAP_PPC_SMT_POSSIBLE capability indicates which virtual SMT
7635 modes are available.                             7635 modes are available.
7636                                                  7636 
7637 7.12 KVM_CAP_PPC_FWNMI                           7637 7.12 KVM_CAP_PPC_FWNMI
7638 ----------------------                           7638 ----------------------
7639                                                  7639 
7640 :Architectures: ppc                              7640 :Architectures: ppc
7641 :Parameters: none                                7641 :Parameters: none
7642                                                  7642 
7643 With this capability a machine check exceptio    7643 With this capability a machine check exception in the guest address
7644 space will cause KVM to exit the guest with N    7644 space will cause KVM to exit the guest with NMI exit reason. This
7645 enables QEMU to build error log and branch to    7645 enables QEMU to build error log and branch to guest kernel registered
7646 machine check handling routine. Without this     7646 machine check handling routine. Without this capability KVM will
7647 branch to guests' 0x200 interrupt vector.        7647 branch to guests' 0x200 interrupt vector.
7648                                                  7648 
7649 7.13 KVM_CAP_X86_DISABLE_EXITS                   7649 7.13 KVM_CAP_X86_DISABLE_EXITS
7650 ------------------------------                   7650 ------------------------------
7651                                                  7651 
7652 :Architectures: x86                              7652 :Architectures: x86
7653 :Parameters: args[0] defines which exits are     7653 :Parameters: args[0] defines which exits are disabled
7654 :Returns: 0 on success, -EINVAL when args[0]     7654 :Returns: 0 on success, -EINVAL when args[0] contains invalid exits
7655                                                  7655 
7656 Valid bits in args[0] are::                      7656 Valid bits in args[0] are::
7657                                                  7657 
7658   #define KVM_X86_DISABLE_EXITS_MWAIT            7658   #define KVM_X86_DISABLE_EXITS_MWAIT            (1 << 0)
7659   #define KVM_X86_DISABLE_EXITS_HLT              7659   #define KVM_X86_DISABLE_EXITS_HLT              (1 << 1)
7660   #define KVM_X86_DISABLE_EXITS_PAUSE            7660   #define KVM_X86_DISABLE_EXITS_PAUSE            (1 << 2)
7661   #define KVM_X86_DISABLE_EXITS_CSTATE           7661   #define KVM_X86_DISABLE_EXITS_CSTATE           (1 << 3)
7662                                                  7662 
7663 Enabling this capability on a VM provides use    7663 Enabling this capability on a VM provides userspace with a way to no
7664 longer intercept some instructions for improv    7664 longer intercept some instructions for improved latency in some
7665 workloads, and is suggested when vCPUs are as    7665 workloads, and is suggested when vCPUs are associated to dedicated
7666 physical CPUs.  More bits can be added in the    7666 physical CPUs.  More bits can be added in the future; userspace can
7667 just pass the KVM_CHECK_EXTENSION result to K    7667 just pass the KVM_CHECK_EXTENSION result to KVM_ENABLE_CAP to disable
7668 all such vmexits.                                7668 all such vmexits.
7669                                                  7669 
7670 Do not enable KVM_FEATURE_PV_UNHALT if you di    7670 Do not enable KVM_FEATURE_PV_UNHALT if you disable HLT exits.
7671                                                  7671 
7672 7.14 KVM_CAP_S390_HPAGE_1M                       7672 7.14 KVM_CAP_S390_HPAGE_1M
7673 --------------------------                       7673 --------------------------
7674                                                  7674 
7675 :Architectures: s390                             7675 :Architectures: s390
7676 :Parameters: none                                7676 :Parameters: none
7677 :Returns: 0 on success, -EINVAL if hpage modu    7677 :Returns: 0 on success, -EINVAL if hpage module parameter was not set
7678           or cmma is enabled, or the VM has t    7678           or cmma is enabled, or the VM has the KVM_VM_S390_UCONTROL
7679           flag set                               7679           flag set
7680                                                  7680 
7681 With this capability the KVM support for memo    7681 With this capability the KVM support for memory backing with 1m pages
7682 through hugetlbfs can be enabled for a VM. Af    7682 through hugetlbfs can be enabled for a VM. After the capability is
7683 enabled, cmma can't be enabled anymore and pf    7683 enabled, cmma can't be enabled anymore and pfmfi and the storage key
7684 interpretation are disabled. If cmma has alre    7684 interpretation are disabled. If cmma has already been enabled or the
7685 hpage module parameter is not set to 1, -EINV    7685 hpage module parameter is not set to 1, -EINVAL is returned.
7686                                                  7686 
7687 While it is generally possible to create a hu    7687 While it is generally possible to create a huge page backed VM without
7688 this capability, the VM will not be able to r    7688 this capability, the VM will not be able to run.
7689                                                  7689 
7690 7.15 KVM_CAP_MSR_PLATFORM_INFO                   7690 7.15 KVM_CAP_MSR_PLATFORM_INFO
7691 ------------------------------                   7691 ------------------------------
7692                                                  7692 
7693 :Architectures: x86                              7693 :Architectures: x86
7694 :Parameters: args[0] whether feature should b    7694 :Parameters: args[0] whether feature should be enabled or not
7695                                                  7695 
7696 With this capability, a guest may read the MS    7696 With this capability, a guest may read the MSR_PLATFORM_INFO MSR. Otherwise,
7697 a #GP would be raised when the guest tries to    7697 a #GP would be raised when the guest tries to access. Currently, this
7698 capability does not enable write permissions     7698 capability does not enable write permissions of this MSR for the guest.
7699                                                  7699 
7700 7.16 KVM_CAP_PPC_NESTED_HV                       7700 7.16 KVM_CAP_PPC_NESTED_HV
7701 --------------------------                       7701 --------------------------
7702                                                  7702 
7703 :Architectures: ppc                              7703 :Architectures: ppc
7704 :Parameters: none                                7704 :Parameters: none
7705 :Returns: 0 on success, -EINVAL when the impl    7705 :Returns: 0 on success, -EINVAL when the implementation doesn't support
7706           nested-HV virtualization.              7706           nested-HV virtualization.
7707                                                  7707 
7708 HV-KVM on POWER9 and later systems allows for    7708 HV-KVM on POWER9 and later systems allows for "nested-HV"
7709 virtualization, which provides a way for a gu    7709 virtualization, which provides a way for a guest VM to run guests that
7710 can run using the CPU's supervisor mode (priv    7710 can run using the CPU's supervisor mode (privileged non-hypervisor
7711 state).  Enabling this capability on a VM dep    7711 state).  Enabling this capability on a VM depends on the CPU having
7712 the necessary functionality and on the facili    7712 the necessary functionality and on the facility being enabled with a
7713 kvm-hv module parameter.                         7713 kvm-hv module parameter.
7714                                                  7714 
7715 7.17 KVM_CAP_EXCEPTION_PAYLOAD                   7715 7.17 KVM_CAP_EXCEPTION_PAYLOAD
7716 ------------------------------                   7716 ------------------------------
7717                                                  7717 
7718 :Architectures: x86                              7718 :Architectures: x86
7719 :Parameters: args[0] whether feature should b    7719 :Parameters: args[0] whether feature should be enabled or not
7720                                                  7720 
7721 With this capability enabled, CR2 will not be    7721 With this capability enabled, CR2 will not be modified prior to the
7722 emulated VM-exit when L1 intercepts a #PF exc    7722 emulated VM-exit when L1 intercepts a #PF exception that occurs in
7723 L2. Similarly, for kvm-intel only, DR6 will n    7723 L2. Similarly, for kvm-intel only, DR6 will not be modified prior to
7724 the emulated VM-exit when L1 intercepts a #DB    7724 the emulated VM-exit when L1 intercepts a #DB exception that occurs in
7725 L2. As a result, when KVM_GET_VCPU_EVENTS rep    7725 L2. As a result, when KVM_GET_VCPU_EVENTS reports a pending #PF (or
7726 #DB) exception for L2, exception.has_payload     7726 #DB) exception for L2, exception.has_payload will be set and the
7727 faulting address (or the new DR6 bits*) will     7727 faulting address (or the new DR6 bits*) will be reported in the
7728 exception_payload field. Similarly, when user    7728 exception_payload field. Similarly, when userspace injects a #PF (or
7729 #DB) into L2 using KVM_SET_VCPU_EVENTS, it is    7729 #DB) into L2 using KVM_SET_VCPU_EVENTS, it is expected to set
7730 exception.has_payload and to put the faulting    7730 exception.has_payload and to put the faulting address - or the new DR6
7731 bits\ [#]_ - in the exception_payload field.     7731 bits\ [#]_ - in the exception_payload field.
7732                                                  7732 
7733 This capability also enables exception.pendin    7733 This capability also enables exception.pending in struct
7734 kvm_vcpu_events, which allows userspace to di    7734 kvm_vcpu_events, which allows userspace to distinguish between pending
7735 and injected exceptions.                         7735 and injected exceptions.
7736                                                  7736 
7737                                                  7737 
7738 .. [#] For the new DR6 bits, note that bit 16    7738 .. [#] For the new DR6 bits, note that bit 16 is set iff the #DB exception
7739        will clear DR6.RTM.                       7739        will clear DR6.RTM.
7740                                                  7740 
7741 7.18 KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2           7741 7.18 KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2
7742 --------------------------------------           7742 --------------------------------------
7743                                                  7743 
7744 :Architectures: x86, arm64, mips                 7744 :Architectures: x86, arm64, mips
7745 :Parameters: args[0] whether feature should b    7745 :Parameters: args[0] whether feature should be enabled or not
7746                                                  7746 
7747 Valid flags are::                                7747 Valid flags are::
7748                                                  7748 
7749   #define KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE    7749   #define KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE   (1 << 0)
7750   #define KVM_DIRTY_LOG_INITIALLY_SET            7750   #define KVM_DIRTY_LOG_INITIALLY_SET           (1 << 1)
7751                                                  7751 
7752 With KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE is s    7752 With KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE is set, KVM_GET_DIRTY_LOG will not
7753 automatically clear and write-protect all pag    7753 automatically clear and write-protect all pages that are returned as dirty.
7754 Rather, userspace will have to do this operat    7754 Rather, userspace will have to do this operation separately using
7755 KVM_CLEAR_DIRTY_LOG.                             7755 KVM_CLEAR_DIRTY_LOG.
7756                                                  7756 
7757 At the cost of a slightly more complicated op    7757 At the cost of a slightly more complicated operation, this provides better
7758 scalability and responsiveness for two reason    7758 scalability and responsiveness for two reasons.  First,
7759 KVM_CLEAR_DIRTY_LOG ioctl can operate on a 64    7759 KVM_CLEAR_DIRTY_LOG ioctl can operate on a 64-page granularity rather
7760 than requiring to sync a full memslot; this e    7760 than requiring to sync a full memslot; this ensures that KVM does not
7761 take spinlocks for an extended period of time    7761 take spinlocks for an extended period of time.  Second, in some cases a
7762 large amount of time can pass between a call     7762 large amount of time can pass between a call to KVM_GET_DIRTY_LOG and
7763 userspace actually using the data in the page    7763 userspace actually using the data in the page.  Pages can be modified
7764 during this time, which is inefficient for bo    7764 during this time, which is inefficient for both the guest and userspace:
7765 the guest will incur a higher penalty due to     7765 the guest will incur a higher penalty due to write protection faults,
7766 while userspace can see false reports of dirt    7766 while userspace can see false reports of dirty pages.  Manual reprotection
7767 helps reducing this time, improving guest per    7767 helps reducing this time, improving guest performance and reducing the
7768 number of dirty log false positives.             7768 number of dirty log false positives.
7769                                                  7769 
7770 With KVM_DIRTY_LOG_INITIALLY_SET set, all the    7770 With KVM_DIRTY_LOG_INITIALLY_SET set, all the bits of the dirty bitmap
7771 will be initialized to 1 when created.  This     7771 will be initialized to 1 when created.  This also improves performance because
7772 dirty logging can be enabled gradually in sma    7772 dirty logging can be enabled gradually in small chunks on the first call
7773 to KVM_CLEAR_DIRTY_LOG.  KVM_DIRTY_LOG_INITIA    7773 to KVM_CLEAR_DIRTY_LOG.  KVM_DIRTY_LOG_INITIALLY_SET depends on
7774 KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE (it is al    7774 KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE (it is also only available on
7775 x86 and arm64 for now).                          7775 x86 and arm64 for now).
7776                                                  7776 
7777 KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 was previou    7777 KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 was previously available under the name
7778 KVM_CAP_MANUAL_DIRTY_LOG_PROTECT, but the imp    7778 KVM_CAP_MANUAL_DIRTY_LOG_PROTECT, but the implementation had bugs that make
7779 it hard or impossible to use it correctly.  T    7779 it hard or impossible to use it correctly.  The availability of
7780 KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 signals tha    7780 KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2 signals that those bugs are fixed.
7781 Userspace should not try to use KVM_CAP_MANUA    7781 Userspace should not try to use KVM_CAP_MANUAL_DIRTY_LOG_PROTECT.
7782                                                  7782 
7783 7.19 KVM_CAP_PPC_SECURE_GUEST                    7783 7.19 KVM_CAP_PPC_SECURE_GUEST
7784 ------------------------------                   7784 ------------------------------
7785                                                  7785 
7786 :Architectures: ppc                              7786 :Architectures: ppc
7787                                                  7787 
7788 This capability indicates that KVM is running    7788 This capability indicates that KVM is running on a host that has
7789 ultravisor firmware and thus can support a se    7789 ultravisor firmware and thus can support a secure guest.  On such a
7790 system, a guest can ask the ultravisor to mak    7790 system, a guest can ask the ultravisor to make it a secure guest,
7791 one whose memory is inaccessible to the host     7791 one whose memory is inaccessible to the host except for pages which
7792 are explicitly requested to be shared with th    7792 are explicitly requested to be shared with the host.  The ultravisor
7793 notifies KVM when a guest requests to become     7793 notifies KVM when a guest requests to become a secure guest, and KVM
7794 has the opportunity to veto the transition.      7794 has the opportunity to veto the transition.
7795                                                  7795 
7796 If present, this capability can be enabled fo    7796 If present, this capability can be enabled for a VM, meaning that KVM
7797 will allow the transition to secure guest mod    7797 will allow the transition to secure guest mode.  Otherwise KVM will
7798 veto the transition.                             7798 veto the transition.
7799                                                  7799 
7800 7.20 KVM_CAP_HALT_POLL                           7800 7.20 KVM_CAP_HALT_POLL
7801 ----------------------                           7801 ----------------------
7802                                                  7802 
7803 :Architectures: all                              7803 :Architectures: all
7804 :Target: VM                                      7804 :Target: VM
7805 :Parameters: args[0] is the maximum poll time    7805 :Parameters: args[0] is the maximum poll time in nanoseconds
7806 :Returns: 0 on success; -1 on error              7806 :Returns: 0 on success; -1 on error
7807                                                  7807 
7808 KVM_CAP_HALT_POLL overrides the kvm.halt_poll    7808 KVM_CAP_HALT_POLL overrides the kvm.halt_poll_ns module parameter to set the
7809 maximum halt-polling time for all vCPUs in th    7809 maximum halt-polling time for all vCPUs in the target VM. This capability can
7810 be invoked at any time and any number of time    7810 be invoked at any time and any number of times to dynamically change the
7811 maximum halt-polling time.                       7811 maximum halt-polling time.
7812                                                  7812 
7813 See Documentation/virt/kvm/halt-polling.rst f    7813 See Documentation/virt/kvm/halt-polling.rst for more information on halt
7814 polling.                                         7814 polling.
7815                                                  7815 
7816 7.21 KVM_CAP_X86_USER_SPACE_MSR                  7816 7.21 KVM_CAP_X86_USER_SPACE_MSR
7817 -------------------------------                  7817 -------------------------------
7818                                                  7818 
7819 :Architectures: x86                              7819 :Architectures: x86
7820 :Target: VM                                      7820 :Target: VM
7821 :Parameters: args[0] contains the mask of KVM    7821 :Parameters: args[0] contains the mask of KVM_MSR_EXIT_REASON_* events to report
7822 :Returns: 0 on success; -1 on error              7822 :Returns: 0 on success; -1 on error
7823                                                  7823 
7824 This capability allows userspace to intercept    7824 This capability allows userspace to intercept RDMSR and WRMSR instructions if
7825 access to an MSR is denied.  By default, KVM     7825 access to an MSR is denied.  By default, KVM injects #GP on denied accesses.
7826                                                  7826 
7827 When a guest requests to read or write an MSR    7827 When a guest requests to read or write an MSR, KVM may not implement all MSRs
7828 that are relevant to a respective system. It     7828 that are relevant to a respective system. It also does not differentiate by
7829 CPU type.                                        7829 CPU type.
7830                                                  7830 
7831 To allow more fine grained control over MSR h    7831 To allow more fine grained control over MSR handling, userspace may enable
7832 this capability. With it enabled, MSR accesse    7832 this capability. With it enabled, MSR accesses that match the mask specified in
7833 args[0] and would trigger a #GP inside the gu    7833 args[0] and would trigger a #GP inside the guest will instead trigger
7834 KVM_EXIT_X86_RDMSR and KVM_EXIT_X86_WRMSR exi    7834 KVM_EXIT_X86_RDMSR and KVM_EXIT_X86_WRMSR exit notifications.  Userspace
7835 can then implement model specific MSR handlin    7835 can then implement model specific MSR handling and/or user notifications
7836 to inform a user that an MSR was not emulated    7836 to inform a user that an MSR was not emulated/virtualized by KVM.
7837                                                  7837 
7838 The valid mask flags are:                        7838 The valid mask flags are:
7839                                                  7839 
7840 ============================ ================    7840 ============================ ===============================================
7841  KVM_MSR_EXIT_REASON_UNKNOWN intercept access    7841  KVM_MSR_EXIT_REASON_UNKNOWN intercept accesses to unknown (to KVM) MSRs
7842  KVM_MSR_EXIT_REASON_INVAL   intercept access    7842  KVM_MSR_EXIT_REASON_INVAL   intercept accesses that are architecturally
7843                              invalid accordin    7843                              invalid according to the vCPU model and/or mode
7844  KVM_MSR_EXIT_REASON_FILTER  intercept access    7844  KVM_MSR_EXIT_REASON_FILTER  intercept accesses that are denied by userspace
7845                              via KVM_X86_SET_    7845                              via KVM_X86_SET_MSR_FILTER
7846 ============================ ================    7846 ============================ ===============================================
7847                                                  7847 
7848 7.22 KVM_CAP_X86_BUS_LOCK_EXIT                   7848 7.22 KVM_CAP_X86_BUS_LOCK_EXIT
7849 -------------------------------                  7849 -------------------------------
7850                                                  7850 
7851 :Architectures: x86                              7851 :Architectures: x86
7852 :Target: VM                                      7852 :Target: VM
7853 :Parameters: args[0] defines the policy used     7853 :Parameters: args[0] defines the policy used when bus locks detected in guest
7854 :Returns: 0 on success, -EINVAL when args[0]     7854 :Returns: 0 on success, -EINVAL when args[0] contains invalid bits
7855                                                  7855 
7856 Valid bits in args[0] are::                      7856 Valid bits in args[0] are::
7857                                                  7857 
7858   #define KVM_BUS_LOCK_DETECTION_OFF      (1     7858   #define KVM_BUS_LOCK_DETECTION_OFF      (1 << 0)
7859   #define KVM_BUS_LOCK_DETECTION_EXIT     (1     7859   #define KVM_BUS_LOCK_DETECTION_EXIT     (1 << 1)
7860                                                  7860 
7861 Enabling this capability on a VM provides use    7861 Enabling this capability on a VM provides userspace with a way to select a
7862 policy to handle the bus locks detected in gu    7862 policy to handle the bus locks detected in guest. Userspace can obtain the
7863 supported modes from the result of KVM_CHECK_    7863 supported modes from the result of KVM_CHECK_EXTENSION and define it through
7864 the KVM_ENABLE_CAP. The supported modes are m    7864 the KVM_ENABLE_CAP. The supported modes are mutually-exclusive.
7865                                                  7865 
7866 This capability allows userspace to force VM     7866 This capability allows userspace to force VM exits on bus locks detected in the
7867 guest, irrespective whether or not the host h    7867 guest, irrespective whether or not the host has enabled split-lock detection
7868 (which triggers an #AC exception that KVM int    7868 (which triggers an #AC exception that KVM intercepts). This capability is
7869 intended to mitigate attacks where a maliciou    7869 intended to mitigate attacks where a malicious/buggy guest can exploit bus
7870 locks to degrade the performance of the whole    7870 locks to degrade the performance of the whole system.
7871                                                  7871 
7872 If KVM_BUS_LOCK_DETECTION_OFF is set, KVM doe    7872 If KVM_BUS_LOCK_DETECTION_OFF is set, KVM doesn't force guest bus locks to VM
7873 exit, although the host kernel's split-lock #    7873 exit, although the host kernel's split-lock #AC detection still applies, if
7874 enabled.                                         7874 enabled.
7875                                                  7875 
7876 If KVM_BUS_LOCK_DETECTION_EXIT is set, KVM en    7876 If KVM_BUS_LOCK_DETECTION_EXIT is set, KVM enables a CPU feature that ensures
7877 bus locks in the guest trigger a VM exit, and    7877 bus locks in the guest trigger a VM exit, and KVM exits to userspace for all
7878 such VM exits, e.g. to allow userspace to thr    7878 such VM exits, e.g. to allow userspace to throttle the offending guest and/or
7879 apply some other policy-based mitigation. Whe    7879 apply some other policy-based mitigation. When exiting to userspace, KVM sets
7880 KVM_RUN_X86_BUS_LOCK in vcpu-run->flags, and     7880 KVM_RUN_X86_BUS_LOCK in vcpu-run->flags, and conditionally sets the exit_reason
7881 to KVM_EXIT_X86_BUS_LOCK.                        7881 to KVM_EXIT_X86_BUS_LOCK.
7882                                                  7882 
7883 Note! Detected bus locks may be coincident wi    7883 Note! Detected bus locks may be coincident with other exits to userspace, i.e.
7884 KVM_RUN_X86_BUS_LOCK should be checked regard    7884 KVM_RUN_X86_BUS_LOCK should be checked regardless of the primary exit reason if
7885 userspace wants to take action on all detecte    7885 userspace wants to take action on all detected bus locks.
7886                                                  7886 
7887 7.23 KVM_CAP_PPC_DAWR1                           7887 7.23 KVM_CAP_PPC_DAWR1
7888 ----------------------                           7888 ----------------------
7889                                                  7889 
7890 :Architectures: ppc                              7890 :Architectures: ppc
7891 :Parameters: none                                7891 :Parameters: none
7892 :Returns: 0 on success, -EINVAL when CPU does    7892 :Returns: 0 on success, -EINVAL when CPU doesn't support 2nd DAWR
7893                                                  7893 
7894 This capability can be used to check / enable    7894 This capability can be used to check / enable 2nd DAWR feature provided
7895 by POWER10 processor.                            7895 by POWER10 processor.
7896                                                  7896 
7897                                                  7897 
7898 7.24 KVM_CAP_VM_COPY_ENC_CONTEXT_FROM            7898 7.24 KVM_CAP_VM_COPY_ENC_CONTEXT_FROM
7899 -------------------------------------            7899 -------------------------------------
7900                                                  7900 
7901 Architectures: x86 SEV enabled                   7901 Architectures: x86 SEV enabled
7902 Type: vm                                         7902 Type: vm
7903 Parameters: args[0] is the fd of the source v    7903 Parameters: args[0] is the fd of the source vm
7904 Returns: 0 on success; ENOTTY on error           7904 Returns: 0 on success; ENOTTY on error
7905                                                  7905 
7906 This capability enables userspace to copy enc    7906 This capability enables userspace to copy encryption context from the vm
7907 indicated by the fd to the vm this is called     7907 indicated by the fd to the vm this is called on.
7908                                                  7908 
7909 This is intended to support in-guest workload    7909 This is intended to support in-guest workloads scheduled by the host. This
7910 allows the in-guest workload to maintain its     7910 allows the in-guest workload to maintain its own NPTs and keeps the two vms
7911 from accidentally clobbering each other with     7911 from accidentally clobbering each other with interrupts and the like (separate
7912 APIC/MSRs/etc).                                  7912 APIC/MSRs/etc).
7913                                                  7913 
7914 7.25 KVM_CAP_SGX_ATTRIBUTE                       7914 7.25 KVM_CAP_SGX_ATTRIBUTE
7915 --------------------------                       7915 --------------------------
7916                                                  7916 
7917 :Architectures: x86                              7917 :Architectures: x86
7918 :Target: VM                                      7918 :Target: VM
7919 :Parameters: args[0] is a file handle of a SG    7919 :Parameters: args[0] is a file handle of a SGX attribute file in securityfs
7920 :Returns: 0 on success, -EINVAL if the file h    7920 :Returns: 0 on success, -EINVAL if the file handle is invalid or if a requested
7921           attribute is not supported by KVM.     7921           attribute is not supported by KVM.
7922                                                  7922 
7923 KVM_CAP_SGX_ATTRIBUTE enables a userspace VMM    7923 KVM_CAP_SGX_ATTRIBUTE enables a userspace VMM to grant a VM access to one or
7924 more privileged enclave attributes.  args[0]     7924 more privileged enclave attributes.  args[0] must hold a file handle to a valid
7925 SGX attribute file corresponding to an attrib    7925 SGX attribute file corresponding to an attribute that is supported/restricted
7926 by KVM (currently only PROVISIONKEY).            7926 by KVM (currently only PROVISIONKEY).
7927                                                  7927 
7928 The SGX subsystem restricts access to a subse    7928 The SGX subsystem restricts access to a subset of enclave attributes to provide
7929 additional security for an uncompromised kern    7929 additional security for an uncompromised kernel, e.g. use of the PROVISIONKEY
7930 is restricted to deter malware from using the    7930 is restricted to deter malware from using the PROVISIONKEY to obtain a stable
7931 system fingerprint.  To prevent userspace fro    7931 system fingerprint.  To prevent userspace from circumventing such restrictions
7932 by running an enclave in a VM, KVM prevents a    7932 by running an enclave in a VM, KVM prevents access to privileged attributes by
7933 default.                                         7933 default.
7934                                                  7934 
7935 See Documentation/arch/x86/sgx.rst for more d    7935 See Documentation/arch/x86/sgx.rst for more details.
7936                                                  7936 
7937 7.26 KVM_CAP_PPC_RPT_INVALIDATE                  7937 7.26 KVM_CAP_PPC_RPT_INVALIDATE
7938 -------------------------------                  7938 -------------------------------
7939                                                  7939 
7940 :Capability: KVM_CAP_PPC_RPT_INVALIDATE          7940 :Capability: KVM_CAP_PPC_RPT_INVALIDATE
7941 :Architectures: ppc                              7941 :Architectures: ppc
7942 :Type: vm                                        7942 :Type: vm
7943                                                  7943 
7944 This capability indicates that the kernel is     7944 This capability indicates that the kernel is capable of handling
7945 H_RPT_INVALIDATE hcall.                          7945 H_RPT_INVALIDATE hcall.
7946                                                  7946 
7947 In order to enable the use of H_RPT_INVALIDAT    7947 In order to enable the use of H_RPT_INVALIDATE in the guest,
7948 user space might have to advertise it for the    7948 user space might have to advertise it for the guest. For example,
7949 IBM pSeries (sPAPR) guest starts using it if     7949 IBM pSeries (sPAPR) guest starts using it if "hcall-rpt-invalidate" is
7950 present in the "ibm,hypertas-functions" devic    7950 present in the "ibm,hypertas-functions" device-tree property.
7951                                                  7951 
7952 This capability is enabled for hypervisors on    7952 This capability is enabled for hypervisors on platforms like POWER9
7953 that support radix MMU.                          7953 that support radix MMU.
7954                                                  7954 
7955 7.27 KVM_CAP_EXIT_ON_EMULATION_FAILURE           7955 7.27 KVM_CAP_EXIT_ON_EMULATION_FAILURE
7956 --------------------------------------           7956 --------------------------------------
7957                                                  7957 
7958 :Architectures: x86                              7958 :Architectures: x86
7959 :Parameters: args[0] whether the feature shou    7959 :Parameters: args[0] whether the feature should be enabled or not
7960                                                  7960 
7961 When this capability is enabled, an emulation    7961 When this capability is enabled, an emulation failure will result in an exit
7962 to userspace with KVM_INTERNAL_ERROR (except     7962 to userspace with KVM_INTERNAL_ERROR (except when the emulator was invoked
7963 to handle a VMware backdoor instruction). Fur    7963 to handle a VMware backdoor instruction). Furthermore, KVM will now provide up
7964 to 15 instruction bytes for any exit to users    7964 to 15 instruction bytes for any exit to userspace resulting from an emulation
7965 failure.  When these exits to userspace occur    7965 failure.  When these exits to userspace occur use the emulation_failure struct
7966 instead of the internal struct.  They both ha    7966 instead of the internal struct.  They both have the same layout, but the
7967 emulation_failure struct matches the content     7967 emulation_failure struct matches the content better.  It also explicitly
7968 defines the 'flags' field which is used to de    7968 defines the 'flags' field which is used to describe the fields in the struct
7969 that are valid (ie: if KVM_INTERNAL_ERROR_EMU    7969 that are valid (ie: if KVM_INTERNAL_ERROR_EMULATION_FLAG_INSTRUCTION_BYTES is
7970 set in the 'flags' field then both 'insn_size    7970 set in the 'flags' field then both 'insn_size' and 'insn_bytes' have valid data
7971 in them.)                                        7971 in them.)
7972                                                  7972 
7973 7.28 KVM_CAP_ARM_MTE                             7973 7.28 KVM_CAP_ARM_MTE
7974 --------------------                             7974 --------------------
7975                                                  7975 
7976 :Architectures: arm64                            7976 :Architectures: arm64
7977 :Parameters: none                                7977 :Parameters: none
7978                                                  7978 
7979 This capability indicates that KVM (and the h    7979 This capability indicates that KVM (and the hardware) supports exposing the
7980 Memory Tagging Extensions (MTE) to the guest.    7980 Memory Tagging Extensions (MTE) to the guest. It must also be enabled by the
7981 VMM before creating any VCPUs to allow the gu    7981 VMM before creating any VCPUs to allow the guest access. Note that MTE is only
7982 available to a guest running in AArch64 mode     7982 available to a guest running in AArch64 mode and enabling this capability will
7983 cause attempts to create AArch32 VCPUs to fai    7983 cause attempts to create AArch32 VCPUs to fail.
7984                                                  7984 
7985 When enabled the guest is able to access tags    7985 When enabled the guest is able to access tags associated with any memory given
7986 to the guest. KVM will ensure that the tags a    7986 to the guest. KVM will ensure that the tags are maintained during swap or
7987 hibernation of the host; however the VMM need    7987 hibernation of the host; however the VMM needs to manually save/restore the
7988 tags as appropriate if the VM is migrated.       7988 tags as appropriate if the VM is migrated.
7989                                                  7989 
7990 When this capability is enabled all memory in    7990 When this capability is enabled all memory in memslots must be mapped as
7991 ``MAP_ANONYMOUS`` or with a RAM-based file ma    7991 ``MAP_ANONYMOUS`` or with a RAM-based file mapping (``tmpfs``, ``memfd``),
7992 attempts to create a memslot with an invalid     7992 attempts to create a memslot with an invalid mmap will result in an
7993 -EINVAL return.                                  7993 -EINVAL return.
7994                                                  7994 
7995 When enabled the VMM may make use of the ``KV    7995 When enabled the VMM may make use of the ``KVM_ARM_MTE_COPY_TAGS`` ioctl to
7996 perform a bulk copy of tags to/from the guest    7996 perform a bulk copy of tags to/from the guest.
7997                                                  7997 
7998 7.29 KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM            7998 7.29 KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM
7999 -------------------------------------            7999 -------------------------------------
8000                                                  8000 
8001 :Architectures: x86 SEV enabled                  8001 :Architectures: x86 SEV enabled
8002 :Type: vm                                        8002 :Type: vm
8003 :Parameters: args[0] is the fd of the source     8003 :Parameters: args[0] is the fd of the source vm
8004 :Returns: 0 on success                           8004 :Returns: 0 on success
8005                                                  8005 
8006 This capability enables userspace to migrate     8006 This capability enables userspace to migrate the encryption context from the VM
8007 indicated by the fd to the VM this is called     8007 indicated by the fd to the VM this is called on.
8008                                                  8008 
8009 This is intended to support intra-host migrat    8009 This is intended to support intra-host migration of VMs between userspace VMMs,
8010 upgrading the VMM process without interruptin    8010 upgrading the VMM process without interrupting the guest.
8011                                                  8011 
8012 7.30 KVM_CAP_PPC_AIL_MODE_3                      8012 7.30 KVM_CAP_PPC_AIL_MODE_3
8013 -------------------------------                  8013 -------------------------------
8014                                                  8014 
8015 :Capability: KVM_CAP_PPC_AIL_MODE_3              8015 :Capability: KVM_CAP_PPC_AIL_MODE_3
8016 :Architectures: ppc                              8016 :Architectures: ppc
8017 :Type: vm                                        8017 :Type: vm
8018                                                  8018 
8019 This capability indicates that the kernel sup    8019 This capability indicates that the kernel supports the mode 3 setting for the
8020 "Address Translation Mode on Interrupt" aka "    8020 "Address Translation Mode on Interrupt" aka "Alternate Interrupt Location"
8021 resource that is controlled with the H_SET_MO    8021 resource that is controlled with the H_SET_MODE hypercall.
8022                                                  8022 
8023 This capability allows a guest kernel to use     8023 This capability allows a guest kernel to use a better-performance mode for
8024 handling interrupts and system calls.            8024 handling interrupts and system calls.
8025                                                  8025 
8026 7.31 KVM_CAP_DISABLE_QUIRKS2                     8026 7.31 KVM_CAP_DISABLE_QUIRKS2
8027 ----------------------------                     8027 ----------------------------
8028                                                  8028 
8029 :Capability: KVM_CAP_DISABLE_QUIRKS2             8029 :Capability: KVM_CAP_DISABLE_QUIRKS2
8030 :Parameters: args[0] - set of KVM quirks to d    8030 :Parameters: args[0] - set of KVM quirks to disable
8031 :Architectures: x86                              8031 :Architectures: x86
8032 :Type: vm                                        8032 :Type: vm
8033                                                  8033 
8034 This capability, if enabled, will cause KVM t    8034 This capability, if enabled, will cause KVM to disable some behavior
8035 quirks.                                          8035 quirks.
8036                                                  8036 
8037 Calling KVM_CHECK_EXTENSION for this capabili    8037 Calling KVM_CHECK_EXTENSION for this capability returns a bitmask of
8038 quirks that can be disabled in KVM.              8038 quirks that can be disabled in KVM.
8039                                                  8039 
8040 The argument to KVM_ENABLE_CAP for this capab    8040 The argument to KVM_ENABLE_CAP for this capability is a bitmask of
8041 quirks to disable, and must be a subset of th    8041 quirks to disable, and must be a subset of the bitmask returned by
8042 KVM_CHECK_EXTENSION.                             8042 KVM_CHECK_EXTENSION.
8043                                                  8043 
8044 The valid bits in cap.args[0] are:               8044 The valid bits in cap.args[0] are:
8045                                                  8045 
8046 =================================== =========    8046 =================================== ============================================
8047  KVM_X86_QUIRK_LINT0_REENABLED      By defaul    8047  KVM_X86_QUIRK_LINT0_REENABLED      By default, the reset value for the LVT
8048                                     LINT0 reg    8048                                     LINT0 register is 0x700 (APIC_MODE_EXTINT).
8049                                     When this    8049                                     When this quirk is disabled, the reset value
8050                                     is 0x1000    8050                                     is 0x10000 (APIC_LVT_MASKED).
8051                                                  8051 
8052  KVM_X86_QUIRK_CD_NW_CLEARED        By defaul    8052  KVM_X86_QUIRK_CD_NW_CLEARED        By default, KVM clears CR0.CD and CR0.NW on
8053                                     AMD CPUs     8053                                     AMD CPUs to workaround buggy guest firmware
8054                                     that runs    8054                                     that runs in perpetuity with CR0.CD, i.e.
8055                                     with cach    8055                                     with caches in "no fill" mode.
8056                                                  8056 
8057                                     When this    8057                                     When this quirk is disabled, KVM does not
8058                                     change th    8058                                     change the value of CR0.CD and CR0.NW.
8059                                                  8059 
8060  KVM_X86_QUIRK_LAPIC_MMIO_HOLE      By defaul    8060  KVM_X86_QUIRK_LAPIC_MMIO_HOLE      By default, the MMIO LAPIC interface is
8061                                     available    8061                                     available even when configured for x2APIC
8062                                     mode. Whe    8062                                     mode. When this quirk is disabled, KVM
8063                                     disables     8063                                     disables the MMIO LAPIC interface if the
8064                                     LAPIC is     8064                                     LAPIC is in x2APIC mode.
8065                                                  8065 
8066  KVM_X86_QUIRK_OUT_7E_INC_RIP       By defaul    8066  KVM_X86_QUIRK_OUT_7E_INC_RIP       By default, KVM pre-increments %rip before
8067                                     exiting t    8067                                     exiting to userspace for an OUT instruction
8068                                     to port 0    8068                                     to port 0x7e. When this quirk is disabled,
8069                                     KVM does     8069                                     KVM does not pre-increment %rip before
8070                                     exiting t    8070                                     exiting to userspace.
8071                                                  8071 
8072  KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT When this    8072  KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT When this quirk is disabled, KVM sets
8073                                     CPUID.01H    8073                                     CPUID.01H:ECX[bit 3] (MONITOR/MWAIT) if
8074                                     IA32_MISC    8074                                     IA32_MISC_ENABLE[bit 18] (MWAIT) is set.
8075                                     Additiona    8075                                     Additionally, when this quirk is disabled,
8076                                     KVM clear    8076                                     KVM clears CPUID.01H:ECX[bit 3] if
8077                                     IA32_MISC    8077                                     IA32_MISC_ENABLE[bit 18] is cleared.
8078                                                  8078 
8079  KVM_X86_QUIRK_FIX_HYPERCALL_INSN   By defaul    8079  KVM_X86_QUIRK_FIX_HYPERCALL_INSN   By default, KVM rewrites guest
8080                                     VMMCALL/V    8080                                     VMMCALL/VMCALL instructions to match the
8081                                     vendor's     8081                                     vendor's hypercall instruction for the
8082                                     system. W    8082                                     system. When this quirk is disabled, KVM
8083                                     will no l    8083                                     will no longer rewrite invalid guest
8084                                     hypercall    8084                                     hypercall instructions. Executing the
8085                                     incorrect    8085                                     incorrect hypercall instruction will
8086                                     generate     8086                                     generate a #UD within the guest.
8087                                                  8087 
8088 KVM_X86_QUIRK_MWAIT_NEVER_UD_FAULTS By defaul    8088 KVM_X86_QUIRK_MWAIT_NEVER_UD_FAULTS By default, KVM emulates MONITOR/MWAIT (if
8089                                     they are     8089                                     they are intercepted) as NOPs regardless of
8090                                     whether o    8090                                     whether or not MONITOR/MWAIT are supported
8091                                     according    8091                                     according to guest CPUID.  When this quirk
8092                                     is disabl    8092                                     is disabled and KVM_X86_DISABLE_EXITS_MWAIT
8093                                     is not se    8093                                     is not set (MONITOR/MWAIT are intercepted),
8094                                     KVM will     8094                                     KVM will inject a #UD on MONITOR/MWAIT if
8095                                     they're u    8095                                     they're unsupported per guest CPUID.  Note,
8096                                     KVM will     8096                                     KVM will modify MONITOR/MWAIT support in
8097                                     guest CPU    8097                                     guest CPUID on writes to MISC_ENABLE if
8098                                     KVM_X86_Q    8098                                     KVM_X86_QUIRK_MISC_ENABLE_NO_MWAIT is
8099                                     disabled.    8099                                     disabled.
8100                                                  8100 
8101 KVM_X86_QUIRK_SLOT_ZAP_ALL          By defaul    8101 KVM_X86_QUIRK_SLOT_ZAP_ALL          By default, for KVM_X86_DEFAULT_VM VMs, KVM
8102                                     invalidat    8102                                     invalidates all SPTEs in all memslots and
8103                                     address s    8103                                     address spaces when a memslot is deleted or
8104                                     moved.  W    8104                                     moved.  When this quirk is disabled (or the
8105                                     VM type i    8105                                     VM type isn't KVM_X86_DEFAULT_VM), KVM only
8106                                     ensures t    8106                                     ensures the backing memory of the deleted
8107                                     or moved     8107                                     or moved memslot isn't reachable, i.e KVM
8108                                     _may_ inv    8108                                     _may_ invalidate only SPTEs related to the
8109                                     memslot.     8109                                     memslot.
8110 =================================== =========    8110 =================================== ============================================
8111                                                  8111 
8112 7.32 KVM_CAP_MAX_VCPU_ID                         8112 7.32 KVM_CAP_MAX_VCPU_ID
8113 ------------------------                         8113 ------------------------
8114                                                  8114 
8115 :Architectures: x86                              8115 :Architectures: x86
8116 :Target: VM                                      8116 :Target: VM
8117 :Parameters: args[0] - maximum APIC ID value     8117 :Parameters: args[0] - maximum APIC ID value set for current VM
8118 :Returns: 0 on success, -EINVAL if args[0] is    8118 :Returns: 0 on success, -EINVAL if args[0] is beyond KVM_MAX_VCPU_IDS
8119           supported in KVM or if it has been     8119           supported in KVM or if it has been set.
8120                                                  8120 
8121 This capability allows userspace to specify m    8121 This capability allows userspace to specify maximum possible APIC ID
8122 assigned for current VM session prior to the     8122 assigned for current VM session prior to the creation of vCPUs, saving
8123 memory for data structures indexed by the API    8123 memory for data structures indexed by the APIC ID.  Userspace is able
8124 to calculate the limit to APIC ID values from    8124 to calculate the limit to APIC ID values from designated
8125 CPU topology.                                    8125 CPU topology.
8126                                                  8126 
8127 The value can be changed only until KVM_ENABL    8127 The value can be changed only until KVM_ENABLE_CAP is set to a nonzero
8128 value or until a vCPU is created.  Upon creat    8128 value or until a vCPU is created.  Upon creation of the first vCPU,
8129 if the value was set to zero or KVM_ENABLE_CA    8129 if the value was set to zero or KVM_ENABLE_CAP was not invoked, KVM
8130 uses the return value of KVM_CHECK_EXTENSION(    8130 uses the return value of KVM_CHECK_EXTENSION(KVM_CAP_MAX_VCPU_ID) as
8131 the maximum APIC ID.                             8131 the maximum APIC ID.
8132                                                  8132 
8133 7.33 KVM_CAP_X86_NOTIFY_VMEXIT                   8133 7.33 KVM_CAP_X86_NOTIFY_VMEXIT
8134 ------------------------------                   8134 ------------------------------
8135                                                  8135 
8136 :Architectures: x86                              8136 :Architectures: x86
8137 :Target: VM                                      8137 :Target: VM
8138 :Parameters: args[0] is the value of notify w    8138 :Parameters: args[0] is the value of notify window as well as some flags
8139 :Returns: 0 on success, -EINVAL if args[0] co    8139 :Returns: 0 on success, -EINVAL if args[0] contains invalid flags or notify
8140           VM exit is unsupported.                8140           VM exit is unsupported.
8141                                                  8141 
8142 Bits 63:32 of args[0] are used for notify win    8142 Bits 63:32 of args[0] are used for notify window.
8143 Bits 31:0 of args[0] are for some flags. Vali    8143 Bits 31:0 of args[0] are for some flags. Valid bits are::
8144                                                  8144 
8145   #define KVM_X86_NOTIFY_VMEXIT_ENABLED    (1    8145   #define KVM_X86_NOTIFY_VMEXIT_ENABLED    (1 << 0)
8146   #define KVM_X86_NOTIFY_VMEXIT_USER       (1    8146   #define KVM_X86_NOTIFY_VMEXIT_USER       (1 << 1)
8147                                                  8147 
8148 This capability allows userspace to configure    8148 This capability allows userspace to configure the notify VM exit on/off
8149 in per-VM scope during VM creation. Notify VM    8149 in per-VM scope during VM creation. Notify VM exit is disabled by default.
8150 When userspace sets KVM_X86_NOTIFY_VMEXIT_ENA    8150 When userspace sets KVM_X86_NOTIFY_VMEXIT_ENABLED bit in args[0], VMM will
8151 enable this feature with the notify window pr    8151 enable this feature with the notify window provided, which will generate
8152 a VM exit if no event window occurs in VM non    8152 a VM exit if no event window occurs in VM non-root mode for a specified of
8153 time (notify window).                            8153 time (notify window).
8154                                                  8154 
8155 If KVM_X86_NOTIFY_VMEXIT_USER is set in args[    8155 If KVM_X86_NOTIFY_VMEXIT_USER is set in args[0], upon notify VM exits happen,
8156 KVM would exit to userspace for handling.        8156 KVM would exit to userspace for handling.
8157                                                  8157 
8158 This capability is aimed to mitigate the thre    8158 This capability is aimed to mitigate the threat that malicious VMs can
8159 cause CPU stuck (due to event windows don't o    8159 cause CPU stuck (due to event windows don't open up) and make the CPU
8160 unavailable to host or other VMs.                8160 unavailable to host or other VMs.
8161                                                  8161 
8162 7.34 KVM_CAP_MEMORY_FAULT_INFO                   8162 7.34 KVM_CAP_MEMORY_FAULT_INFO
8163 ------------------------------                   8163 ------------------------------
8164                                                  8164 
8165 :Architectures: x86                              8165 :Architectures: x86
8166 :Returns: Informational only, -EINVAL on dire    8166 :Returns: Informational only, -EINVAL on direct KVM_ENABLE_CAP.
8167                                                  8167 
8168 The presence of this capability indicates tha    8168 The presence of this capability indicates that KVM_RUN will fill
8169 kvm_run.memory_fault if KVM cannot resolve a     8169 kvm_run.memory_fault if KVM cannot resolve a guest page fault VM-Exit, e.g. if
8170 there is a valid memslot but no backing VMA f    8170 there is a valid memslot but no backing VMA for the corresponding host virtual
8171 address.                                         8171 address.
8172                                                  8172 
8173 The information in kvm_run.memory_fault is va    8173 The information in kvm_run.memory_fault is valid if and only if KVM_RUN returns
8174 an error with errno=EFAULT or errno=EHWPOISON    8174 an error with errno=EFAULT or errno=EHWPOISON *and* kvm_run.exit_reason is set
8175 to KVM_EXIT_MEMORY_FAULT.                        8175 to KVM_EXIT_MEMORY_FAULT.
8176                                                  8176 
8177 Note: Userspaces which attempt to resolve mem    8177 Note: Userspaces which attempt to resolve memory faults so that they can retry
8178 KVM_RUN are encouraged to guard against repea    8178 KVM_RUN are encouraged to guard against repeatedly receiving the same
8179 error/annotated fault.                           8179 error/annotated fault.
8180                                                  8180 
8181 See KVM_EXIT_MEMORY_FAULT for more informatio    8181 See KVM_EXIT_MEMORY_FAULT for more information.
8182                                                  8182 
8183 7.35 KVM_CAP_X86_APIC_BUS_CYCLES_NS              8183 7.35 KVM_CAP_X86_APIC_BUS_CYCLES_NS
8184 -----------------------------------              8184 -----------------------------------
8185                                                  8185 
8186 :Architectures: x86                              8186 :Architectures: x86
8187 :Target: VM                                      8187 :Target: VM
8188 :Parameters: args[0] is the desired APIC bus     8188 :Parameters: args[0] is the desired APIC bus clock rate, in nanoseconds
8189 :Returns: 0 on success, -EINVAL if args[0] co    8189 :Returns: 0 on success, -EINVAL if args[0] contains an invalid value for the
8190           frequency or if any vCPUs have been    8190           frequency or if any vCPUs have been created, -ENXIO if a virtual
8191           local APIC has not been created usi    8191           local APIC has not been created using KVM_CREATE_IRQCHIP.
8192                                                  8192 
8193 This capability sets the VM's APIC bus clock     8193 This capability sets the VM's APIC bus clock frequency, used by KVM's in-kernel
8194 virtual APIC when emulating APIC timers.  KVM    8194 virtual APIC when emulating APIC timers.  KVM's default value can be retrieved
8195 by KVM_CHECK_EXTENSION.                          8195 by KVM_CHECK_EXTENSION.
8196                                                  8196 
8197 Note: Userspace is responsible for correctly     8197 Note: Userspace is responsible for correctly configuring CPUID 0x15, a.k.a. the
8198 core crystal clock frequency, if a non-zero C    8198 core crystal clock frequency, if a non-zero CPUID 0x15 is exposed to the guest.
8199                                                  8199 
8200 7.36 KVM_CAP_X86_GUEST_MODE                      8200 7.36 KVM_CAP_X86_GUEST_MODE
8201 ------------------------------                   8201 ------------------------------
8202                                                  8202 
8203 :Architectures: x86                              8203 :Architectures: x86
8204 :Returns: Informational only, -EINVAL on dire    8204 :Returns: Informational only, -EINVAL on direct KVM_ENABLE_CAP.
8205                                                  8205 
8206 The presence of this capability indicates tha    8206 The presence of this capability indicates that KVM_RUN will update the
8207 KVM_RUN_X86_GUEST_MODE bit in kvm_run.flags t    8207 KVM_RUN_X86_GUEST_MODE bit in kvm_run.flags to indicate whether the
8208 vCPU was executing nested guest code when it     8208 vCPU was executing nested guest code when it exited.
8209                                                  8209 
8210 KVM exits with the register state of either t    8210 KVM exits with the register state of either the L1 or L2 guest
8211 depending on which executed at the time of an    8211 depending on which executed at the time of an exit. Userspace must
8212 take care to differentiate between these case    8212 take care to differentiate between these cases.
8213                                                  8213 
8214 8. Other capabilities.                           8214 8. Other capabilities.
8215 ======================                           8215 ======================
8216                                                  8216 
8217 This section lists capabilities that give inf    8217 This section lists capabilities that give information about other
8218 features of the KVM implementation.              8218 features of the KVM implementation.
8219                                                  8219 
8220 8.1 KVM_CAP_PPC_HWRNG                            8220 8.1 KVM_CAP_PPC_HWRNG
8221 ---------------------                            8221 ---------------------
8222                                                  8222 
8223 :Architectures: ppc                              8223 :Architectures: ppc
8224                                                  8224 
8225 This capability, if KVM_CHECK_EXTENSION indic    8225 This capability, if KVM_CHECK_EXTENSION indicates that it is
8226 available, means that the kernel has an imple    8226 available, means that the kernel has an implementation of the
8227 H_RANDOM hypercall backed by a hardware rando    8227 H_RANDOM hypercall backed by a hardware random-number generator.
8228 If present, the kernel H_RANDOM handler can b    8228 If present, the kernel H_RANDOM handler can be enabled for guest use
8229 with the KVM_CAP_PPC_ENABLE_HCALL capability.    8229 with the KVM_CAP_PPC_ENABLE_HCALL capability.
8230                                                  8230 
8231 8.2 KVM_CAP_HYPERV_SYNIC                         8231 8.2 KVM_CAP_HYPERV_SYNIC
8232 ------------------------                         8232 ------------------------
8233                                                  8233 
8234 :Architectures: x86                              8234 :Architectures: x86
8235                                                  8235 
8236 This capability, if KVM_CHECK_EXTENSION indic    8236 This capability, if KVM_CHECK_EXTENSION indicates that it is
8237 available, means that the kernel has an imple    8237 available, means that the kernel has an implementation of the
8238 Hyper-V Synthetic interrupt controller(SynIC)    8238 Hyper-V Synthetic interrupt controller(SynIC). Hyper-V SynIC is
8239 used to support Windows Hyper-V based guest p    8239 used to support Windows Hyper-V based guest paravirt drivers(VMBus).
8240                                                  8240 
8241 In order to use SynIC, it has to be activated    8241 In order to use SynIC, it has to be activated by setting this
8242 capability via KVM_ENABLE_CAP ioctl on the vc    8242 capability via KVM_ENABLE_CAP ioctl on the vcpu fd. Note that this
8243 will disable the use of APIC hardware virtual    8243 will disable the use of APIC hardware virtualization even if supported
8244 by the CPU, as it's incompatible with SynIC a    8244 by the CPU, as it's incompatible with SynIC auto-EOI behavior.
8245                                                  8245 
8246 8.3 KVM_CAP_PPC_MMU_RADIX                        8246 8.3 KVM_CAP_PPC_MMU_RADIX
8247 -------------------------                        8247 -------------------------
8248                                                  8248 
8249 :Architectures: ppc                              8249 :Architectures: ppc
8250                                                  8250 
8251 This capability, if KVM_CHECK_EXTENSION indic    8251 This capability, if KVM_CHECK_EXTENSION indicates that it is
8252 available, means that the kernel can support     8252 available, means that the kernel can support guests using the
8253 radix MMU defined in Power ISA V3.00 (as impl    8253 radix MMU defined in Power ISA V3.00 (as implemented in the POWER9
8254 processor).                                      8254 processor).
8255                                                  8255 
8256 8.4 KVM_CAP_PPC_MMU_HASH_V3                      8256 8.4 KVM_CAP_PPC_MMU_HASH_V3
8257 ---------------------------                      8257 ---------------------------
8258                                                  8258 
8259 :Architectures: ppc                              8259 :Architectures: ppc
8260                                                  8260 
8261 This capability, if KVM_CHECK_EXTENSION indic    8261 This capability, if KVM_CHECK_EXTENSION indicates that it is
8262 available, means that the kernel can support     8262 available, means that the kernel can support guests using the
8263 hashed page table MMU defined in Power ISA V3    8263 hashed page table MMU defined in Power ISA V3.00 (as implemented in
8264 the POWER9 processor), including in-memory se    8264 the POWER9 processor), including in-memory segment tables.
8265                                                  8265 
8266 8.5 KVM_CAP_MIPS_VZ                              8266 8.5 KVM_CAP_MIPS_VZ
8267 -------------------                              8267 -------------------
8268                                                  8268 
8269 :Architectures: mips                             8269 :Architectures: mips
8270                                                  8270 
8271 This capability, if KVM_CHECK_EXTENSION on th    8271 This capability, if KVM_CHECK_EXTENSION on the main kvm handle indicates that
8272 it is available, means that full hardware ass    8272 it is available, means that full hardware assisted virtualization capabilities
8273 of the hardware are available for use through    8273 of the hardware are available for use through KVM. An appropriate
8274 KVM_VM_MIPS_* type must be passed to KVM_CREA    8274 KVM_VM_MIPS_* type must be passed to KVM_CREATE_VM to create a VM which
8275 utilises it.                                     8275 utilises it.
8276                                                  8276 
8277 If KVM_CHECK_EXTENSION on a kvm VM handle ind    8277 If KVM_CHECK_EXTENSION on a kvm VM handle indicates that this capability is
8278 available, it means that the VM is using full    8278 available, it means that the VM is using full hardware assisted virtualization
8279 capabilities of the hardware. This is useful     8279 capabilities of the hardware. This is useful to check after creating a VM with
8280 KVM_VM_MIPS_DEFAULT.                             8280 KVM_VM_MIPS_DEFAULT.
8281                                                  8281 
8282 The value returned by KVM_CHECK_EXTENSION sho    8282 The value returned by KVM_CHECK_EXTENSION should be compared against known
8283 values (see below). All other values are rese    8283 values (see below). All other values are reserved. This is to allow for the
8284 possibility of other hardware assisted virtua    8284 possibility of other hardware assisted virtualization implementations which
8285 may be incompatible with the MIPS VZ ASE.        8285 may be incompatible with the MIPS VZ ASE.
8286                                                  8286 
8287 ==  =========================================    8287 ==  ==========================================================================
8288  0  The trap & emulate implementation is in u    8288  0  The trap & emulate implementation is in use to run guest code in user
8289     mode. Guest virtual memory segments are r    8289     mode. Guest virtual memory segments are rearranged to fit the guest in the
8290     user mode address space.                     8290     user mode address space.
8291                                                  8291 
8292  1  The MIPS VZ ASE is in use, providing full    8292  1  The MIPS VZ ASE is in use, providing full hardware assisted
8293     virtualization, including standard guest     8293     virtualization, including standard guest virtual memory segments.
8294 ==  =========================================    8294 ==  ==========================================================================
8295                                                  8295 
8296 8.6 KVM_CAP_MIPS_TE                              8296 8.6 KVM_CAP_MIPS_TE
8297 -------------------                              8297 -------------------
8298                                                  8298 
8299 :Architectures: mips                             8299 :Architectures: mips
8300                                                  8300 
8301 This capability, if KVM_CHECK_EXTENSION on th    8301 This capability, if KVM_CHECK_EXTENSION on the main kvm handle indicates that
8302 it is available, means that the trap & emulat    8302 it is available, means that the trap & emulate implementation is available to
8303 run guest code in user mode, even if KVM_CAP_    8303 run guest code in user mode, even if KVM_CAP_MIPS_VZ indicates that hardware
8304 assisted virtualisation is also available. KV    8304 assisted virtualisation is also available. KVM_VM_MIPS_TE (0) must be passed
8305 to KVM_CREATE_VM to create a VM which utilise    8305 to KVM_CREATE_VM to create a VM which utilises it.
8306                                                  8306 
8307 If KVM_CHECK_EXTENSION on a kvm VM handle ind    8307 If KVM_CHECK_EXTENSION on a kvm VM handle indicates that this capability is
8308 available, it means that the VM is using trap    8308 available, it means that the VM is using trap & emulate.
8309                                                  8309 
8310 8.7 KVM_CAP_MIPS_64BIT                           8310 8.7 KVM_CAP_MIPS_64BIT
8311 ----------------------                           8311 ----------------------
8312                                                  8312 
8313 :Architectures: mips                             8313 :Architectures: mips
8314                                                  8314 
8315 This capability indicates the supported archi    8315 This capability indicates the supported architecture type of the guest, i.e. the
8316 supported register and address width.            8316 supported register and address width.
8317                                                  8317 
8318 The values returned when this capability is c    8318 The values returned when this capability is checked by KVM_CHECK_EXTENSION on a
8319 kvm VM handle correspond roughly to the CP0_C    8319 kvm VM handle correspond roughly to the CP0_Config.AT register field, and should
8320 be checked specifically against known values     8320 be checked specifically against known values (see below). All other values are
8321 reserved.                                        8321 reserved.
8322                                                  8322 
8323 ==  =========================================    8323 ==  ========================================================================
8324  0  MIPS32 or microMIPS32.                       8324  0  MIPS32 or microMIPS32.
8325     Both registers and addresses are 32-bits     8325     Both registers and addresses are 32-bits wide.
8326     It will only be possible to run 32-bit gu    8326     It will only be possible to run 32-bit guest code.
8327                                                  8327 
8328  1  MIPS64 or microMIPS64 with access only to    8328  1  MIPS64 or microMIPS64 with access only to 32-bit compatibility segments.
8329     Registers are 64-bits wide, but addresses    8329     Registers are 64-bits wide, but addresses are 32-bits wide.
8330     64-bit guest code may run but cannot acce    8330     64-bit guest code may run but cannot access MIPS64 memory segments.
8331     It will also be possible to run 32-bit gu    8331     It will also be possible to run 32-bit guest code.
8332                                                  8332 
8333  2  MIPS64 or microMIPS64 with access to all     8333  2  MIPS64 or microMIPS64 with access to all address segments.
8334     Both registers and addresses are 64-bits     8334     Both registers and addresses are 64-bits wide.
8335     It will be possible to run 64-bit or 32-b    8335     It will be possible to run 64-bit or 32-bit guest code.
8336 ==  =========================================    8336 ==  ========================================================================
8337                                                  8337 
8338 8.9 KVM_CAP_ARM_USER_IRQ                         8338 8.9 KVM_CAP_ARM_USER_IRQ
8339 ------------------------                         8339 ------------------------
8340                                                  8340 
8341 :Architectures: arm64                            8341 :Architectures: arm64
8342                                                  8342 
8343 This capability, if KVM_CHECK_EXTENSION indic    8343 This capability, if KVM_CHECK_EXTENSION indicates that it is available, means
8344 that if userspace creates a VM without an in-    8344 that if userspace creates a VM without an in-kernel interrupt controller, it
8345 will be notified of changes to the output lev    8345 will be notified of changes to the output level of in-kernel emulated devices,
8346 which can generate virtual interrupts, presen    8346 which can generate virtual interrupts, presented to the VM.
8347 For such VMs, on every return to userspace, t    8347 For such VMs, on every return to userspace, the kernel
8348 updates the vcpu's run->s.regs.device_irq_lev    8348 updates the vcpu's run->s.regs.device_irq_level field to represent the actual
8349 output level of the device.                      8349 output level of the device.
8350                                                  8350 
8351 Whenever kvm detects a change in the device o    8351 Whenever kvm detects a change in the device output level, kvm guarantees at
8352 least one return to userspace before running     8352 least one return to userspace before running the VM.  This exit could either
8353 be a KVM_EXIT_INTR or any other exit event, l    8353 be a KVM_EXIT_INTR or any other exit event, like KVM_EXIT_MMIO. This way,
8354 userspace can always sample the device output    8354 userspace can always sample the device output level and re-compute the state of
8355 the userspace interrupt controller.  Userspac    8355 the userspace interrupt controller.  Userspace should always check the state
8356 of run->s.regs.device_irq_level on every kvm     8356 of run->s.regs.device_irq_level on every kvm exit.
8357 The value in run->s.regs.device_irq_level can    8357 The value in run->s.regs.device_irq_level can represent both level and edge
8358 triggered interrupt signals, depending on the    8358 triggered interrupt signals, depending on the device.  Edge triggered interrupt
8359 signals will exit to userspace with the bit i    8359 signals will exit to userspace with the bit in run->s.regs.device_irq_level
8360 set exactly once per edge signal.                8360 set exactly once per edge signal.
8361                                                  8361 
8362 The field run->s.regs.device_irq_level is ava    8362 The field run->s.regs.device_irq_level is available independent of
8363 run->kvm_valid_regs or run->kvm_dirty_regs bi    8363 run->kvm_valid_regs or run->kvm_dirty_regs bits.
8364                                                  8364 
8365 If KVM_CAP_ARM_USER_IRQ is supported, the KVM    8365 If KVM_CAP_ARM_USER_IRQ is supported, the KVM_CHECK_EXTENSION ioctl returns a
8366 number larger than 0 indicating the version o    8366 number larger than 0 indicating the version of this capability is implemented
8367 and thereby which bits in run->s.regs.device_    8367 and thereby which bits in run->s.regs.device_irq_level can signal values.
8368                                                  8368 
8369 Currently the following bits are defined for     8369 Currently the following bits are defined for the device_irq_level bitmap::
8370                                                  8370 
8371   KVM_CAP_ARM_USER_IRQ >= 1:                     8371   KVM_CAP_ARM_USER_IRQ >= 1:
8372                                                  8372 
8373     KVM_ARM_DEV_EL1_VTIMER -  EL1 virtual tim    8373     KVM_ARM_DEV_EL1_VTIMER -  EL1 virtual timer
8374     KVM_ARM_DEV_EL1_PTIMER -  EL1 physical ti    8374     KVM_ARM_DEV_EL1_PTIMER -  EL1 physical timer
8375     KVM_ARM_DEV_PMU        -  ARM PMU overflo    8375     KVM_ARM_DEV_PMU        -  ARM PMU overflow interrupt signal
8376                                                  8376 
8377 Future versions of kvm may implement addition    8377 Future versions of kvm may implement additional events. These will get
8378 indicated by returning a higher number from K    8378 indicated by returning a higher number from KVM_CHECK_EXTENSION and will be
8379 listed above.                                    8379 listed above.
8380                                                  8380 
8381 8.10 KVM_CAP_PPC_SMT_POSSIBLE                    8381 8.10 KVM_CAP_PPC_SMT_POSSIBLE
8382 -----------------------------                    8382 -----------------------------
8383                                                  8383 
8384 :Architectures: ppc                              8384 :Architectures: ppc
8385                                                  8385 
8386 Querying this capability returns a bitmap ind    8386 Querying this capability returns a bitmap indicating the possible
8387 virtual SMT modes that can be set using KVM_C    8387 virtual SMT modes that can be set using KVM_CAP_PPC_SMT.  If bit N
8388 (counting from the right) is set, then a virt    8388 (counting from the right) is set, then a virtual SMT mode of 2^N is
8389 available.                                       8389 available.
8390                                                  8390 
8391 8.11 KVM_CAP_HYPERV_SYNIC2                       8391 8.11 KVM_CAP_HYPERV_SYNIC2
8392 --------------------------                       8392 --------------------------
8393                                                  8393 
8394 :Architectures: x86                              8394 :Architectures: x86
8395                                                  8395 
8396 This capability enables a newer version of Hy    8396 This capability enables a newer version of Hyper-V Synthetic interrupt
8397 controller (SynIC).  The only difference with    8397 controller (SynIC).  The only difference with KVM_CAP_HYPERV_SYNIC is that KVM
8398 doesn't clear SynIC message and event flags p    8398 doesn't clear SynIC message and event flags pages when they are enabled by
8399 writing to the respective MSRs.                  8399 writing to the respective MSRs.
8400                                                  8400 
8401 8.12 KVM_CAP_HYPERV_VP_INDEX                     8401 8.12 KVM_CAP_HYPERV_VP_INDEX
8402 ----------------------------                     8402 ----------------------------
8403                                                  8403 
8404 :Architectures: x86                              8404 :Architectures: x86
8405                                                  8405 
8406 This capability indicates that userspace can     8406 This capability indicates that userspace can load HV_X64_MSR_VP_INDEX msr.  Its
8407 value is used to denote the target vcpu for a    8407 value is used to denote the target vcpu for a SynIC interrupt.  For
8408 compatibility, KVM initializes this msr to KV    8408 compatibility, KVM initializes this msr to KVM's internal vcpu index.  When this
8409 capability is absent, userspace can still que    8409 capability is absent, userspace can still query this msr's value.
8410                                                  8410 
8411 8.13 KVM_CAP_S390_AIS_MIGRATION                  8411 8.13 KVM_CAP_S390_AIS_MIGRATION
8412 -------------------------------                  8412 -------------------------------
8413                                                  8413 
8414 :Architectures: s390                             8414 :Architectures: s390
8415 :Parameters: none                                8415 :Parameters: none
8416                                                  8416 
8417 This capability indicates if the flic device     8417 This capability indicates if the flic device will be able to get/set the
8418 AIS states for migration via the KVM_DEV_FLIC    8418 AIS states for migration via the KVM_DEV_FLIC_AISM_ALL attribute and allows
8419 to discover this without having to create a f    8419 to discover this without having to create a flic device.
8420                                                  8420 
8421 8.14 KVM_CAP_S390_PSW                            8421 8.14 KVM_CAP_S390_PSW
8422 ---------------------                            8422 ---------------------
8423                                                  8423 
8424 :Architectures: s390                             8424 :Architectures: s390
8425                                                  8425 
8426 This capability indicates that the PSW is exp    8426 This capability indicates that the PSW is exposed via the kvm_run structure.
8427                                                  8427 
8428 8.15 KVM_CAP_S390_GMAP                           8428 8.15 KVM_CAP_S390_GMAP
8429 ----------------------                           8429 ----------------------
8430                                                  8430 
8431 :Architectures: s390                             8431 :Architectures: s390
8432                                                  8432 
8433 This capability indicates that the user space    8433 This capability indicates that the user space memory used as guest mapping can
8434 be anywhere in the user memory address space,    8434 be anywhere in the user memory address space, as long as the memory slots are
8435 aligned and sized to a segment (1MB) boundary    8435 aligned and sized to a segment (1MB) boundary.
8436                                                  8436 
8437 8.16 KVM_CAP_S390_COW                            8437 8.16 KVM_CAP_S390_COW
8438 ---------------------                            8438 ---------------------
8439                                                  8439 
8440 :Architectures: s390                             8440 :Architectures: s390
8441                                                  8441 
8442 This capability indicates that the user space    8442 This capability indicates that the user space memory used as guest mapping can
8443 use copy-on-write semantics as well as dirty     8443 use copy-on-write semantics as well as dirty pages tracking via read-only page
8444 tables.                                          8444 tables.
8445                                                  8445 
8446 8.17 KVM_CAP_S390_BPB                            8446 8.17 KVM_CAP_S390_BPB
8447 ---------------------                            8447 ---------------------
8448                                                  8448 
8449 :Architectures: s390                             8449 :Architectures: s390
8450                                                  8450 
8451 This capability indicates that kvm will imple    8451 This capability indicates that kvm will implement the interfaces to handle
8452 reset, migration and nested KVM for branch pr    8452 reset, migration and nested KVM for branch prediction blocking. The stfle
8453 facility 82 should not be provided to the gue    8453 facility 82 should not be provided to the guest without this capability.
8454                                                  8454 
8455 8.18 KVM_CAP_HYPERV_TLBFLUSH                     8455 8.18 KVM_CAP_HYPERV_TLBFLUSH
8456 ----------------------------                     8456 ----------------------------
8457                                                  8457 
8458 :Architectures: x86                              8458 :Architectures: x86
8459                                                  8459 
8460 This capability indicates that KVM supports p    8460 This capability indicates that KVM supports paravirtualized Hyper-V TLB Flush
8461 hypercalls:                                      8461 hypercalls:
8462 HvFlushVirtualAddressSpace, HvFlushVirtualAdd    8462 HvFlushVirtualAddressSpace, HvFlushVirtualAddressSpaceEx,
8463 HvFlushVirtualAddressList, HvFlushVirtualAddr    8463 HvFlushVirtualAddressList, HvFlushVirtualAddressListEx.
8464                                                  8464 
8465 8.19 KVM_CAP_ARM_INJECT_SERROR_ESR               8465 8.19 KVM_CAP_ARM_INJECT_SERROR_ESR
8466 ----------------------------------               8466 ----------------------------------
8467                                                  8467 
8468 :Architectures: arm64                            8468 :Architectures: arm64
8469                                                  8469 
8470 This capability indicates that userspace can     8470 This capability indicates that userspace can specify (via the
8471 KVM_SET_VCPU_EVENTS ioctl) the syndrome value    8471 KVM_SET_VCPU_EVENTS ioctl) the syndrome value reported to the guest when it
8472 takes a virtual SError interrupt exception.      8472 takes a virtual SError interrupt exception.
8473 If KVM advertises this capability, userspace     8473 If KVM advertises this capability, userspace can only specify the ISS field for
8474 the ESR syndrome. Other parts of the ESR, suc    8474 the ESR syndrome. Other parts of the ESR, such as the EC are generated by the
8475 CPU when the exception is taken. If this virt    8475 CPU when the exception is taken. If this virtual SError is taken to EL1 using
8476 AArch64, this value will be reported in the I    8476 AArch64, this value will be reported in the ISS field of ESR_ELx.
8477                                                  8477 
8478 See KVM_CAP_VCPU_EVENTS for more details.        8478 See KVM_CAP_VCPU_EVENTS for more details.
8479                                                  8479 
8480 8.20 KVM_CAP_HYPERV_SEND_IPI                     8480 8.20 KVM_CAP_HYPERV_SEND_IPI
8481 ----------------------------                     8481 ----------------------------
8482                                                  8482 
8483 :Architectures: x86                              8483 :Architectures: x86
8484                                                  8484 
8485 This capability indicates that KVM supports p    8485 This capability indicates that KVM supports paravirtualized Hyper-V IPI send
8486 hypercalls:                                      8486 hypercalls:
8487 HvCallSendSyntheticClusterIpi, HvCallSendSynt    8487 HvCallSendSyntheticClusterIpi, HvCallSendSyntheticClusterIpiEx.
8488                                                  8488 
8489 8.21 KVM_CAP_HYPERV_DIRECT_TLBFLUSH              8489 8.21 KVM_CAP_HYPERV_DIRECT_TLBFLUSH
8490 -----------------------------------              8490 -----------------------------------
8491                                                  8491 
8492 :Architectures: x86                              8492 :Architectures: x86
8493                                                  8493 
8494 This capability indicates that KVM running on    8494 This capability indicates that KVM running on top of Hyper-V hypervisor
8495 enables Direct TLB flush for its guests meani    8495 enables Direct TLB flush for its guests meaning that TLB flush
8496 hypercalls are handled by Level 0 hypervisor     8496 hypercalls are handled by Level 0 hypervisor (Hyper-V) bypassing KVM.
8497 Due to the different ABI for hypercall parame    8497 Due to the different ABI for hypercall parameters between Hyper-V and
8498 KVM, enabling this capability effectively dis    8498 KVM, enabling this capability effectively disables all hypercall
8499 handling by KVM (as some KVM hypercall may be    8499 handling by KVM (as some KVM hypercall may be mistakenly treated as TLB
8500 flush hypercalls by Hyper-V) so userspace sho    8500 flush hypercalls by Hyper-V) so userspace should disable KVM identification
8501 in CPUID and only exposes Hyper-V identificat    8501 in CPUID and only exposes Hyper-V identification. In this case, guest
8502 thinks it's running on Hyper-V and only use H    8502 thinks it's running on Hyper-V and only use Hyper-V hypercalls.
8503                                                  8503 
8504 8.22 KVM_CAP_S390_VCPU_RESETS                    8504 8.22 KVM_CAP_S390_VCPU_RESETS
8505 -----------------------------                    8505 -----------------------------
8506                                                  8506 
8507 :Architectures: s390                             8507 :Architectures: s390
8508                                                  8508 
8509 This capability indicates that the KVM_S390_N    8509 This capability indicates that the KVM_S390_NORMAL_RESET and
8510 KVM_S390_CLEAR_RESET ioctls are available.       8510 KVM_S390_CLEAR_RESET ioctls are available.
8511                                                  8511 
8512 8.23 KVM_CAP_S390_PROTECTED                      8512 8.23 KVM_CAP_S390_PROTECTED
8513 ---------------------------                      8513 ---------------------------
8514                                                  8514 
8515 :Architectures: s390                             8515 :Architectures: s390
8516                                                  8516 
8517 This capability indicates that the Ultravisor    8517 This capability indicates that the Ultravisor has been initialized and
8518 KVM can therefore start protected VMs.           8518 KVM can therefore start protected VMs.
8519 This capability governs the KVM_S390_PV_COMMA    8519 This capability governs the KVM_S390_PV_COMMAND ioctl and the
8520 KVM_MP_STATE_LOAD MP_STATE. KVM_SET_MP_STATE     8520 KVM_MP_STATE_LOAD MP_STATE. KVM_SET_MP_STATE can fail for protected
8521 guests when the state change is invalid.         8521 guests when the state change is invalid.
8522                                                  8522 
8523 8.24 KVM_CAP_STEAL_TIME                          8523 8.24 KVM_CAP_STEAL_TIME
8524 -----------------------                          8524 -----------------------
8525                                                  8525 
8526 :Architectures: arm64, x86                       8526 :Architectures: arm64, x86
8527                                                  8527 
8528 This capability indicates that KVM supports s    8528 This capability indicates that KVM supports steal time accounting.
8529 When steal time accounting is supported it ma    8529 When steal time accounting is supported it may be enabled with
8530 architecture-specific interfaces.  This capab    8530 architecture-specific interfaces.  This capability and the architecture-
8531 specific interfaces must be consistent, i.e.     8531 specific interfaces must be consistent, i.e. if one says the feature
8532 is supported, than the other should as well a    8532 is supported, than the other should as well and vice versa.  For arm64
8533 see Documentation/virt/kvm/devices/vcpu.rst "    8533 see Documentation/virt/kvm/devices/vcpu.rst "KVM_ARM_VCPU_PVTIME_CTRL".
8534 For x86 see Documentation/virt/kvm/x86/msr.rs    8534 For x86 see Documentation/virt/kvm/x86/msr.rst "MSR_KVM_STEAL_TIME".
8535                                                  8535 
8536 8.25 KVM_CAP_S390_DIAG318                        8536 8.25 KVM_CAP_S390_DIAG318
8537 -------------------------                        8537 -------------------------
8538                                                  8538 
8539 :Architectures: s390                             8539 :Architectures: s390
8540                                                  8540 
8541 This capability enables a guest to set inform    8541 This capability enables a guest to set information about its control program
8542 (i.e. guest kernel type and version). The inf    8542 (i.e. guest kernel type and version). The information is helpful during
8543 system/firmware service events, providing add    8543 system/firmware service events, providing additional data about the guest
8544 environments running on the machine.             8544 environments running on the machine.
8545                                                  8545 
8546 The information is associated with the DIAGNO    8546 The information is associated with the DIAGNOSE 0x318 instruction, which sets
8547 an 8-byte value consisting of a one-byte Cont    8547 an 8-byte value consisting of a one-byte Control Program Name Code (CPNC) and
8548 a 7-byte Control Program Version Code (CPVC).    8548 a 7-byte Control Program Version Code (CPVC). The CPNC determines what
8549 environment the control program is running in    8549 environment the control program is running in (e.g. Linux, z/VM...), and the
8550 CPVC is used for information specific to OS (    8550 CPVC is used for information specific to OS (e.g. Linux version, Linux
8551 distribution...)                                 8551 distribution...)
8552                                                  8552 
8553 If this capability is available, then the CPN    8553 If this capability is available, then the CPNC and CPVC can be synchronized
8554 between KVM and userspace via the sync regs m    8554 between KVM and userspace via the sync regs mechanism (KVM_SYNC_DIAG318).
8555                                                  8555 
8556 8.26 KVM_CAP_X86_USER_SPACE_MSR                  8556 8.26 KVM_CAP_X86_USER_SPACE_MSR
8557 -------------------------------                  8557 -------------------------------
8558                                                  8558 
8559 :Architectures: x86                              8559 :Architectures: x86
8560                                                  8560 
8561 This capability indicates that KVM supports d    8561 This capability indicates that KVM supports deflection of MSR reads and
8562 writes to user space. It can be enabled on a     8562 writes to user space. It can be enabled on a VM level. If enabled, MSR
8563 accesses that would usually trigger a #GP by     8563 accesses that would usually trigger a #GP by KVM into the guest will
8564 instead get bounced to user space through the    8564 instead get bounced to user space through the KVM_EXIT_X86_RDMSR and
8565 KVM_EXIT_X86_WRMSR exit notifications.           8565 KVM_EXIT_X86_WRMSR exit notifications.
8566                                                  8566 
8567 8.27 KVM_CAP_X86_MSR_FILTER                      8567 8.27 KVM_CAP_X86_MSR_FILTER
8568 ---------------------------                      8568 ---------------------------
8569                                                  8569 
8570 :Architectures: x86                              8570 :Architectures: x86
8571                                                  8571 
8572 This capability indicates that KVM supports t    8572 This capability indicates that KVM supports that accesses to user defined MSRs
8573 may be rejected. With this capability exposed    8573 may be rejected. With this capability exposed, KVM exports new VM ioctl
8574 KVM_X86_SET_MSR_FILTER which user space can c    8574 KVM_X86_SET_MSR_FILTER which user space can call to specify bitmaps of MSR
8575 ranges that KVM should deny access to.           8575 ranges that KVM should deny access to.
8576                                                  8576 
8577 In combination with KVM_CAP_X86_USER_SPACE_MS    8577 In combination with KVM_CAP_X86_USER_SPACE_MSR, this allows user space to
8578 trap and emulate MSRs that are outside of the    8578 trap and emulate MSRs that are outside of the scope of KVM as well as
8579 limit the attack surface on KVM's MSR emulati    8579 limit the attack surface on KVM's MSR emulation code.
8580                                                  8580 
8581 8.28 KVM_CAP_ENFORCE_PV_FEATURE_CPUID            8581 8.28 KVM_CAP_ENFORCE_PV_FEATURE_CPUID
8582 -------------------------------------            8582 -------------------------------------
8583                                                  8583 
8584 Architectures: x86                               8584 Architectures: x86
8585                                                  8585 
8586 When enabled, KVM will disable paravirtual fe    8586 When enabled, KVM will disable paravirtual features provided to the
8587 guest according to the bits in the KVM_CPUID_    8587 guest according to the bits in the KVM_CPUID_FEATURES CPUID leaf
8588 (0x40000001). Otherwise, a guest may use the     8588 (0x40000001). Otherwise, a guest may use the paravirtual features
8589 regardless of what has actually been exposed     8589 regardless of what has actually been exposed through the CPUID leaf.
8590                                                  8590 
8591 8.29 KVM_CAP_DIRTY_LOG_RING/KVM_CAP_DIRTY_LOG    8591 8.29 KVM_CAP_DIRTY_LOG_RING/KVM_CAP_DIRTY_LOG_RING_ACQ_REL
8592 ---------------------------------------------    8592 ----------------------------------------------------------
8593                                                  8593 
8594 :Architectures: x86, arm64                       8594 :Architectures: x86, arm64
8595 :Parameters: args[0] - size of the dirty log     8595 :Parameters: args[0] - size of the dirty log ring
8596                                                  8596 
8597 KVM is capable of tracking dirty memory using    8597 KVM is capable of tracking dirty memory using ring buffers that are
8598 mmapped into userspace; there is one dirty ri    8598 mmapped into userspace; there is one dirty ring per vcpu.
8599                                                  8599 
8600 The dirty ring is available to userspace as a    8600 The dirty ring is available to userspace as an array of
8601 ``struct kvm_dirty_gfn``.  Each dirty entry i    8601 ``struct kvm_dirty_gfn``.  Each dirty entry is defined as::
8602                                                  8602 
8603   struct kvm_dirty_gfn {                         8603   struct kvm_dirty_gfn {
8604           __u32 flags;                           8604           __u32 flags;
8605           __u32 slot; /* as_id | slot_id */      8605           __u32 slot; /* as_id | slot_id */
8606           __u64 offset;                          8606           __u64 offset;
8607   };                                             8607   };
8608                                                  8608 
8609 The following values are defined for the flag    8609 The following values are defined for the flags field to define the
8610 current state of the entry::                     8610 current state of the entry::
8611                                                  8611 
8612   #define KVM_DIRTY_GFN_F_DIRTY           BIT    8612   #define KVM_DIRTY_GFN_F_DIRTY           BIT(0)
8613   #define KVM_DIRTY_GFN_F_RESET           BIT    8613   #define KVM_DIRTY_GFN_F_RESET           BIT(1)
8614   #define KVM_DIRTY_GFN_F_MASK            0x3    8614   #define KVM_DIRTY_GFN_F_MASK            0x3
8615                                                  8615 
8616 Userspace should call KVM_ENABLE_CAP ioctl ri    8616 Userspace should call KVM_ENABLE_CAP ioctl right after KVM_CREATE_VM
8617 ioctl to enable this capability for the new g    8617 ioctl to enable this capability for the new guest and set the size of
8618 the rings.  Enabling the capability is only a    8618 the rings.  Enabling the capability is only allowed before creating any
8619 vCPU, and the size of the ring must be a powe    8619 vCPU, and the size of the ring must be a power of two.  The larger the
8620 ring buffer, the less likely the ring is full    8620 ring buffer, the less likely the ring is full and the VM is forced to
8621 exit to userspace. The optimal size depends o    8621 exit to userspace. The optimal size depends on the workload, but it is
8622 recommended that it be at least 64 KiB (4096     8622 recommended that it be at least 64 KiB (4096 entries).
8623                                                  8623 
8624 Just like for dirty page bitmaps, the buffer     8624 Just like for dirty page bitmaps, the buffer tracks writes to
8625 all user memory regions for which the KVM_MEM    8625 all user memory regions for which the KVM_MEM_LOG_DIRTY_PAGES flag was
8626 set in KVM_SET_USER_MEMORY_REGION.  Once a me    8626 set in KVM_SET_USER_MEMORY_REGION.  Once a memory region is registered
8627 with the flag set, userspace can start harves    8627 with the flag set, userspace can start harvesting dirty pages from the
8628 ring buffer.                                     8628 ring buffer.
8629                                                  8629 
8630 An entry in the ring buffer can be unused (fl    8630 An entry in the ring buffer can be unused (flag bits ``00``),
8631 dirty (flag bits ``01``) or harvested (flag b    8631 dirty (flag bits ``01``) or harvested (flag bits ``1X``).  The
8632 state machine for the entry is as follows::      8632 state machine for the entry is as follows::
8633                                                  8633 
8634           dirtied         harvested        re    8634           dirtied         harvested        reset
8635      00 -----------> 01 -------------> 1X ---    8635      00 -----------> 01 -------------> 1X -------+
8636       ^                                          8636       ^                                          |
8637       |                                          8637       |                                          |
8638       +--------------------------------------    8638       +------------------------------------------+
8639                                                  8639 
8640 To harvest the dirty pages, userspace accesse    8640 To harvest the dirty pages, userspace accesses the mmapped ring buffer
8641 to read the dirty GFNs.  If the flags has the    8641 to read the dirty GFNs.  If the flags has the DIRTY bit set (at this stage
8642 the RESET bit must be cleared), then it means    8642 the RESET bit must be cleared), then it means this GFN is a dirty GFN.
8643 The userspace should harvest this GFN and mar    8643 The userspace should harvest this GFN and mark the flags from state
8644 ``01b`` to ``1Xb`` (bit 0 will be ignored by     8644 ``01b`` to ``1Xb`` (bit 0 will be ignored by KVM, but bit 1 must be set
8645 to show that this GFN is harvested and waitin    8645 to show that this GFN is harvested and waiting for a reset), and move
8646 on to the next GFN.  The userspace should con    8646 on to the next GFN.  The userspace should continue to do this until the
8647 flags of a GFN have the DIRTY bit cleared, me    8647 flags of a GFN have the DIRTY bit cleared, meaning that it has harvested
8648 all the dirty GFNs that were available.          8648 all the dirty GFNs that were available.
8649                                                  8649 
8650 Note that on weakly ordered architectures, us    8650 Note that on weakly ordered architectures, userspace accesses to the
8651 ring buffer (and more specifically the 'flags    8651 ring buffer (and more specifically the 'flags' field) must be ordered,
8652 using load-acquire/store-release accessors wh    8652 using load-acquire/store-release accessors when available, or any
8653 other memory barrier that will ensure this or    8653 other memory barrier that will ensure this ordering.
8654                                                  8654 
8655 It's not necessary for userspace to harvest t    8655 It's not necessary for userspace to harvest the all dirty GFNs at once.
8656 However it must collect the dirty GFNs in seq    8656 However it must collect the dirty GFNs in sequence, i.e., the userspace
8657 program cannot skip one dirty GFN to collect     8657 program cannot skip one dirty GFN to collect the one next to it.
8658                                                  8658 
8659 After processing one or more entries in the r    8659 After processing one or more entries in the ring buffer, userspace
8660 calls the VM ioctl KVM_RESET_DIRTY_RINGS to n    8660 calls the VM ioctl KVM_RESET_DIRTY_RINGS to notify the kernel about
8661 it, so that the kernel will reprotect those c    8661 it, so that the kernel will reprotect those collected GFNs.
8662 Therefore, the ioctl must be called *before*     8662 Therefore, the ioctl must be called *before* reading the content of
8663 the dirty pages.                                 8663 the dirty pages.
8664                                                  8664 
8665 The dirty ring can get full.  When it happens    8665 The dirty ring can get full.  When it happens, the KVM_RUN of the
8666 vcpu will return with exit reason KVM_EXIT_DI    8666 vcpu will return with exit reason KVM_EXIT_DIRTY_LOG_FULL.
8667                                                  8667 
8668 The dirty ring interface has a major differen    8668 The dirty ring interface has a major difference comparing to the
8669 KVM_GET_DIRTY_LOG interface in that, when rea    8669 KVM_GET_DIRTY_LOG interface in that, when reading the dirty ring from
8670 userspace, it's still possible that the kerne    8670 userspace, it's still possible that the kernel has not yet flushed the
8671 processor's dirty page buffers into the kerne    8671 processor's dirty page buffers into the kernel buffer (with dirty bitmaps, the
8672 flushing is done by the KVM_GET_DIRTY_LOG ioc    8672 flushing is done by the KVM_GET_DIRTY_LOG ioctl).  To achieve that, one
8673 needs to kick the vcpu out of KVM_RUN using a    8673 needs to kick the vcpu out of KVM_RUN using a signal.  The resulting
8674 vmexit ensures that all dirty GFNs are flushe    8674 vmexit ensures that all dirty GFNs are flushed to the dirty rings.
8675                                                  8675 
8676 NOTE: KVM_CAP_DIRTY_LOG_RING_ACQ_REL is the o    8676 NOTE: KVM_CAP_DIRTY_LOG_RING_ACQ_REL is the only capability that
8677 should be exposed by weakly ordered architect    8677 should be exposed by weakly ordered architecture, in order to indicate
8678 the additional memory ordering requirements i    8678 the additional memory ordering requirements imposed on userspace when
8679 reading the state of an entry and mutating it    8679 reading the state of an entry and mutating it from DIRTY to HARVESTED.
8680 Architecture with TSO-like ordering (such as     8680 Architecture with TSO-like ordering (such as x86) are allowed to
8681 expose both KVM_CAP_DIRTY_LOG_RING and KVM_CA    8681 expose both KVM_CAP_DIRTY_LOG_RING and KVM_CAP_DIRTY_LOG_RING_ACQ_REL
8682 to userspace.                                    8682 to userspace.
8683                                                  8683 
8684 After enabling the dirty rings, the userspace    8684 After enabling the dirty rings, the userspace needs to detect the
8685 capability of KVM_CAP_DIRTY_LOG_RING_WITH_BIT    8685 capability of KVM_CAP_DIRTY_LOG_RING_WITH_BITMAP to see whether the
8686 ring structures can be backed by per-slot bit    8686 ring structures can be backed by per-slot bitmaps. With this capability
8687 advertised, it means the architecture can dir    8687 advertised, it means the architecture can dirty guest pages without
8688 vcpu/ring context, so that some of the dirty     8688 vcpu/ring context, so that some of the dirty information will still be
8689 maintained in the bitmap structure. KVM_CAP_D    8689 maintained in the bitmap structure. KVM_CAP_DIRTY_LOG_RING_WITH_BITMAP
8690 can't be enabled if the capability of KVM_CAP    8690 can't be enabled if the capability of KVM_CAP_DIRTY_LOG_RING_ACQ_REL
8691 hasn't been enabled, or any memslot has been     8691 hasn't been enabled, or any memslot has been existing.
8692                                                  8692 
8693 Note that the bitmap here is only a backup of    8693 Note that the bitmap here is only a backup of the ring structure. The
8694 use of the ring and bitmap combination is onl    8694 use of the ring and bitmap combination is only beneficial if there is
8695 only a very small amount of memory that is di    8695 only a very small amount of memory that is dirtied out of vcpu/ring
8696 context. Otherwise, the stand-alone per-slot     8696 context. Otherwise, the stand-alone per-slot bitmap mechanism needs to
8697 be considered.                                   8697 be considered.
8698                                                  8698 
8699 To collect dirty bits in the backup bitmap, u    8699 To collect dirty bits in the backup bitmap, userspace can use the same
8700 KVM_GET_DIRTY_LOG ioctl. KVM_CLEAR_DIRTY_LOG     8700 KVM_GET_DIRTY_LOG ioctl. KVM_CLEAR_DIRTY_LOG isn't needed as long as all
8701 the generation of the dirty bits is done in a    8701 the generation of the dirty bits is done in a single pass. Collecting
8702 the dirty bitmap should be the very last thin    8702 the dirty bitmap should be the very last thing that the VMM does before
8703 considering the state as complete. VMM needs     8703 considering the state as complete. VMM needs to ensure that the dirty
8704 state is final and avoid missing dirty pages     8704 state is final and avoid missing dirty pages from another ioctl ordered
8705 after the bitmap collection.                     8705 after the bitmap collection.
8706                                                  8706 
8707 NOTE: Multiple examples of using the backup b    8707 NOTE: Multiple examples of using the backup bitmap: (1) save vgic/its
8708 tables through command KVM_DEV_ARM_{VGIC_GRP_    8708 tables through command KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_SAVE_TABLES} on
8709 KVM device "kvm-arm-vgic-its". (2) restore vg    8709 KVM device "kvm-arm-vgic-its". (2) restore vgic/its tables through
8710 command KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_RESTO    8710 command KVM_DEV_ARM_{VGIC_GRP_CTRL, ITS_RESTORE_TABLES} on KVM device
8711 "kvm-arm-vgic-its". VGICv3 LPI pending status    8711 "kvm-arm-vgic-its". VGICv3 LPI pending status is restored. (3) save
8712 vgic3 pending table through KVM_DEV_ARM_VGIC_    8712 vgic3 pending table through KVM_DEV_ARM_VGIC_{GRP_CTRL, SAVE_PENDING_TABLES}
8713 command on KVM device "kvm-arm-vgic-v3".         8713 command on KVM device "kvm-arm-vgic-v3".
8714                                                  8714 
8715 8.30 KVM_CAP_XEN_HVM                             8715 8.30 KVM_CAP_XEN_HVM
8716 --------------------                             8716 --------------------
8717                                                  8717 
8718 :Architectures: x86                              8718 :Architectures: x86
8719                                                  8719 
8720 This capability indicates the features that X    8720 This capability indicates the features that Xen supports for hosting Xen
8721 PVHVM guests. Valid flags are::                  8721 PVHVM guests. Valid flags are::
8722                                                  8722 
8723   #define KVM_XEN_HVM_CONFIG_HYPERCALL_MSR       8723   #define KVM_XEN_HVM_CONFIG_HYPERCALL_MSR              (1 << 0)
8724   #define KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL     8724   #define KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL            (1 << 1)
8725   #define KVM_XEN_HVM_CONFIG_SHARED_INFO         8725   #define KVM_XEN_HVM_CONFIG_SHARED_INFO                (1 << 2)
8726   #define KVM_XEN_HVM_CONFIG_RUNSTATE            8726   #define KVM_XEN_HVM_CONFIG_RUNSTATE                   (1 << 3)
8727   #define KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL       8727   #define KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL              (1 << 4)
8728   #define KVM_XEN_HVM_CONFIG_EVTCHN_SEND         8728   #define KVM_XEN_HVM_CONFIG_EVTCHN_SEND                (1 << 5)
8729   #define KVM_XEN_HVM_CONFIG_RUNSTATE_UPDATE_    8729   #define KVM_XEN_HVM_CONFIG_RUNSTATE_UPDATE_FLAG       (1 << 6)
8730   #define KVM_XEN_HVM_CONFIG_PVCLOCK_TSC_UNST    8730   #define KVM_XEN_HVM_CONFIG_PVCLOCK_TSC_UNSTABLE       (1 << 7)
8731                                                  8731 
8732 The KVM_XEN_HVM_CONFIG_HYPERCALL_MSR flag ind    8732 The KVM_XEN_HVM_CONFIG_HYPERCALL_MSR flag indicates that the KVM_XEN_HVM_CONFIG
8733 ioctl is available, for the guest to set its     8733 ioctl is available, for the guest to set its hypercall page.
8734                                                  8734 
8735 If KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL is also    8735 If KVM_XEN_HVM_CONFIG_INTERCEPT_HCALL is also set, the same flag may also be
8736 provided in the flags to KVM_XEN_HVM_CONFIG,     8736 provided in the flags to KVM_XEN_HVM_CONFIG, without providing hypercall page
8737 contents, to request that KVM generate hyperc    8737 contents, to request that KVM generate hypercall page content automatically
8738 and also enable interception of guest hyperca    8738 and also enable interception of guest hypercalls with KVM_EXIT_XEN.
8739                                                  8739 
8740 The KVM_XEN_HVM_CONFIG_SHARED_INFO flag indic    8740 The KVM_XEN_HVM_CONFIG_SHARED_INFO flag indicates the availability of the
8741 KVM_XEN_HVM_SET_ATTR, KVM_XEN_HVM_GET_ATTR, K    8741 KVM_XEN_HVM_SET_ATTR, KVM_XEN_HVM_GET_ATTR, KVM_XEN_VCPU_SET_ATTR and
8742 KVM_XEN_VCPU_GET_ATTR ioctls, as well as the     8742 KVM_XEN_VCPU_GET_ATTR ioctls, as well as the delivery of exception vectors
8743 for event channel upcalls when the evtchn_upc    8743 for event channel upcalls when the evtchn_upcall_pending field of a vcpu's
8744 vcpu_info is set.                                8744 vcpu_info is set.
8745                                                  8745 
8746 The KVM_XEN_HVM_CONFIG_RUNSTATE flag indicate    8746 The KVM_XEN_HVM_CONFIG_RUNSTATE flag indicates that the runstate-related
8747 features KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADDR    8747 features KVM_XEN_VCPU_ATTR_TYPE_RUNSTATE_ADDR/_CURRENT/_DATA/_ADJUST are
8748 supported by the KVM_XEN_VCPU_SET_ATTR/KVM_XE    8748 supported by the KVM_XEN_VCPU_SET_ATTR/KVM_XEN_VCPU_GET_ATTR ioctls.
8749                                                  8749 
8750 The KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL flag ind    8750 The KVM_XEN_HVM_CONFIG_EVTCHN_2LEVEL flag indicates that IRQ routing entries
8751 of the type KVM_IRQ_ROUTING_XEN_EVTCHN are su    8751 of the type KVM_IRQ_ROUTING_XEN_EVTCHN are supported, with the priority
8752 field set to indicate 2 level event channel d    8752 field set to indicate 2 level event channel delivery.
8753                                                  8753 
8754 The KVM_XEN_HVM_CONFIG_EVTCHN_SEND flag indic    8754 The KVM_XEN_HVM_CONFIG_EVTCHN_SEND flag indicates that KVM supports
8755 injecting event channel events directly into     8755 injecting event channel events directly into the guest with the
8756 KVM_XEN_HVM_EVTCHN_SEND ioctl. It also indica    8756 KVM_XEN_HVM_EVTCHN_SEND ioctl. It also indicates support for the
8757 KVM_XEN_ATTR_TYPE_EVTCHN/XEN_VERSION HVM attr    8757 KVM_XEN_ATTR_TYPE_EVTCHN/XEN_VERSION HVM attributes and the
8758 KVM_XEN_VCPU_ATTR_TYPE_VCPU_ID/TIMER/UPCALL_V    8758 KVM_XEN_VCPU_ATTR_TYPE_VCPU_ID/TIMER/UPCALL_VECTOR vCPU attributes.
8759 related to event channel delivery, timers, an    8759 related to event channel delivery, timers, and the XENVER_version
8760 interception.                                    8760 interception.
8761                                                  8761 
8762 The KVM_XEN_HVM_CONFIG_RUNSTATE_UPDATE_FLAG f    8762 The KVM_XEN_HVM_CONFIG_RUNSTATE_UPDATE_FLAG flag indicates that KVM supports
8763 the KVM_XEN_ATTR_TYPE_RUNSTATE_UPDATE_FLAG at    8763 the KVM_XEN_ATTR_TYPE_RUNSTATE_UPDATE_FLAG attribute in the KVM_XEN_SET_ATTR
8764 and KVM_XEN_GET_ATTR ioctls. This controls wh    8764 and KVM_XEN_GET_ATTR ioctls. This controls whether KVM will set the
8765 XEN_RUNSTATE_UPDATE flag in guest memory mapp    8765 XEN_RUNSTATE_UPDATE flag in guest memory mapped vcpu_runstate_info during
8766 updates of the runstate information. Note tha    8766 updates of the runstate information. Note that versions of KVM which support
8767 the RUNSTATE feature above, but not the RUNST    8767 the RUNSTATE feature above, but not the RUNSTATE_UPDATE_FLAG feature, will
8768 always set the XEN_RUNSTATE_UPDATE flag when     8768 always set the XEN_RUNSTATE_UPDATE flag when updating the guest structure,
8769 which is perhaps counterintuitive. When this     8769 which is perhaps counterintuitive. When this flag is advertised, KVM will
8770 behave more correctly, not using the XEN_RUNS    8770 behave more correctly, not using the XEN_RUNSTATE_UPDATE flag until/unless
8771 specifically enabled (by the guest making the    8771 specifically enabled (by the guest making the hypercall, causing the VMM
8772 to enable the KVM_XEN_ATTR_TYPE_RUNSTATE_UPDA    8772 to enable the KVM_XEN_ATTR_TYPE_RUNSTATE_UPDATE_FLAG attribute).
8773                                                  8773 
8774 The KVM_XEN_HVM_CONFIG_PVCLOCK_TSC_UNSTABLE f    8774 The KVM_XEN_HVM_CONFIG_PVCLOCK_TSC_UNSTABLE flag indicates that KVM supports
8775 clearing the PVCLOCK_TSC_STABLE_BIT flag in X    8775 clearing the PVCLOCK_TSC_STABLE_BIT flag in Xen pvclock sources. This will be
8776 done when the KVM_CAP_XEN_HVM ioctl sets the     8776 done when the KVM_CAP_XEN_HVM ioctl sets the
8777 KVM_XEN_HVM_CONFIG_PVCLOCK_TSC_UNSTABLE flag.    8777 KVM_XEN_HVM_CONFIG_PVCLOCK_TSC_UNSTABLE flag.
8778                                                  8778 
8779 8.31 KVM_CAP_PPC_MULTITCE                        8779 8.31 KVM_CAP_PPC_MULTITCE
8780 -------------------------                        8780 -------------------------
8781                                                  8781 
8782 :Capability: KVM_CAP_PPC_MULTITCE                8782 :Capability: KVM_CAP_PPC_MULTITCE
8783 :Architectures: ppc                              8783 :Architectures: ppc
8784 :Type: vm                                        8784 :Type: vm
8785                                                  8785 
8786 This capability means the kernel is capable o    8786 This capability means the kernel is capable of handling hypercalls
8787 H_PUT_TCE_INDIRECT and H_STUFF_TCE without pa    8787 H_PUT_TCE_INDIRECT and H_STUFF_TCE without passing those into the user
8788 space. This significantly accelerates DMA ope    8788 space. This significantly accelerates DMA operations for PPC KVM guests.
8789 User space should expect that its handlers fo    8789 User space should expect that its handlers for these hypercalls
8790 are not going to be called if user space prev    8790 are not going to be called if user space previously registered LIOBN
8791 in KVM (via KVM_CREATE_SPAPR_TCE or similar c    8791 in KVM (via KVM_CREATE_SPAPR_TCE or similar calls).
8792                                                  8792 
8793 In order to enable H_PUT_TCE_INDIRECT and H_S    8793 In order to enable H_PUT_TCE_INDIRECT and H_STUFF_TCE use in the guest,
8794 user space might have to advertise it for the    8794 user space might have to advertise it for the guest. For example,
8795 IBM pSeries (sPAPR) guest starts using them i    8795 IBM pSeries (sPAPR) guest starts using them if "hcall-multi-tce" is
8796 present in the "ibm,hypertas-functions" devic    8796 present in the "ibm,hypertas-functions" device-tree property.
8797                                                  8797 
8798 The hypercalls mentioned above may or may not    8798 The hypercalls mentioned above may or may not be processed successfully
8799 in the kernel based fast path. If they can no    8799 in the kernel based fast path. If they can not be handled by the kernel,
8800 they will get passed on to user space. So use    8800 they will get passed on to user space. So user space still has to have
8801 an implementation for these despite the in ke    8801 an implementation for these despite the in kernel acceleration.
8802                                                  8802 
8803 This capability is always enabled.               8803 This capability is always enabled.
8804                                                  8804 
8805 8.32 KVM_CAP_PTP_KVM                             8805 8.32 KVM_CAP_PTP_KVM
8806 --------------------                             8806 --------------------
8807                                                  8807 
8808 :Architectures: arm64                            8808 :Architectures: arm64
8809                                                  8809 
8810 This capability indicates that the KVM virtua    8810 This capability indicates that the KVM virtual PTP service is
8811 supported in the host. A VMM can check whethe    8811 supported in the host. A VMM can check whether the service is
8812 available to the guest on migration.             8812 available to the guest on migration.
8813                                                  8813 
8814 8.33 KVM_CAP_HYPERV_ENFORCE_CPUID                8814 8.33 KVM_CAP_HYPERV_ENFORCE_CPUID
8815 ---------------------------------                8815 ---------------------------------
8816                                                  8816 
8817 Architectures: x86                               8817 Architectures: x86
8818                                                  8818 
8819 When enabled, KVM will disable emulated Hyper    8819 When enabled, KVM will disable emulated Hyper-V features provided to the
8820 guest according to the bits Hyper-V CPUID fea    8820 guest according to the bits Hyper-V CPUID feature leaves. Otherwise, all
8821 currently implemented Hyper-V features are pr    8821 currently implemented Hyper-V features are provided unconditionally when
8822 Hyper-V identification is set in the HYPERV_C    8822 Hyper-V identification is set in the HYPERV_CPUID_INTERFACE (0x40000001)
8823 leaf.                                            8823 leaf.
8824                                                  8824 
8825 8.34 KVM_CAP_EXIT_HYPERCALL                      8825 8.34 KVM_CAP_EXIT_HYPERCALL
8826 ---------------------------                      8826 ---------------------------
8827                                                  8827 
8828 :Capability: KVM_CAP_EXIT_HYPERCALL              8828 :Capability: KVM_CAP_EXIT_HYPERCALL
8829 :Architectures: x86                              8829 :Architectures: x86
8830 :Type: vm                                        8830 :Type: vm
8831                                                  8831 
8832 This capability, if enabled, will cause KVM t    8832 This capability, if enabled, will cause KVM to exit to userspace
8833 with KVM_EXIT_HYPERCALL exit reason to proces    8833 with KVM_EXIT_HYPERCALL exit reason to process some hypercalls.
8834                                                  8834 
8835 Calling KVM_CHECK_EXTENSION for this capabili    8835 Calling KVM_CHECK_EXTENSION for this capability will return a bitmask
8836 of hypercalls that can be configured to exit     8836 of hypercalls that can be configured to exit to userspace.
8837 Right now, the only such hypercall is KVM_HC_    8837 Right now, the only such hypercall is KVM_HC_MAP_GPA_RANGE.
8838                                                  8838 
8839 The argument to KVM_ENABLE_CAP is also a bitm    8839 The argument to KVM_ENABLE_CAP is also a bitmask, and must be a subset
8840 of the result of KVM_CHECK_EXTENSION.  KVM wi    8840 of the result of KVM_CHECK_EXTENSION.  KVM will forward to userspace
8841 the hypercalls whose corresponding bit is in     8841 the hypercalls whose corresponding bit is in the argument, and return
8842 ENOSYS for the others.                           8842 ENOSYS for the others.
8843                                                  8843 
8844 8.35 KVM_CAP_PMU_CAPABILITY                      8844 8.35 KVM_CAP_PMU_CAPABILITY
8845 ---------------------------                      8845 ---------------------------
8846                                                  8846 
8847 :Capability: KVM_CAP_PMU_CAPABILITY              8847 :Capability: KVM_CAP_PMU_CAPABILITY
8848 :Architectures: x86                              8848 :Architectures: x86
8849 :Type: vm                                        8849 :Type: vm
8850 :Parameters: arg[0] is bitmask of PMU virtual    8850 :Parameters: arg[0] is bitmask of PMU virtualization capabilities.
8851 :Returns: 0 on success, -EINVAL when arg[0] c    8851 :Returns: 0 on success, -EINVAL when arg[0] contains invalid bits
8852                                                  8852 
8853 This capability alters PMU virtualization in     8853 This capability alters PMU virtualization in KVM.
8854                                                  8854 
8855 Calling KVM_CHECK_EXTENSION for this capabili    8855 Calling KVM_CHECK_EXTENSION for this capability returns a bitmask of
8856 PMU virtualization capabilities that can be a    8856 PMU virtualization capabilities that can be adjusted on a VM.
8857                                                  8857 
8858 The argument to KVM_ENABLE_CAP is also a bitm    8858 The argument to KVM_ENABLE_CAP is also a bitmask and selects specific
8859 PMU virtualization capabilities to be applied    8859 PMU virtualization capabilities to be applied to the VM.  This can
8860 only be invoked on a VM prior to the creation    8860 only be invoked on a VM prior to the creation of VCPUs.
8861                                                  8861 
8862 At this time, KVM_PMU_CAP_DISABLE is the only    8862 At this time, KVM_PMU_CAP_DISABLE is the only capability.  Setting
8863 this capability will disable PMU virtualizati    8863 this capability will disable PMU virtualization for that VM.  Usermode
8864 should adjust CPUID leaf 0xA to reflect that     8864 should adjust CPUID leaf 0xA to reflect that the PMU is disabled.
8865                                                  8865 
8866 8.36 KVM_CAP_ARM_SYSTEM_SUSPEND                  8866 8.36 KVM_CAP_ARM_SYSTEM_SUSPEND
8867 -------------------------------                  8867 -------------------------------
8868                                                  8868 
8869 :Capability: KVM_CAP_ARM_SYSTEM_SUSPEND          8869 :Capability: KVM_CAP_ARM_SYSTEM_SUSPEND
8870 :Architectures: arm64                            8870 :Architectures: arm64
8871 :Type: vm                                        8871 :Type: vm
8872                                                  8872 
8873 When enabled, KVM will exit to userspace with    8873 When enabled, KVM will exit to userspace with KVM_EXIT_SYSTEM_EVENT of
8874 type KVM_SYSTEM_EVENT_SUSPEND to process the     8874 type KVM_SYSTEM_EVENT_SUSPEND to process the guest suspend request.
8875                                                  8875 
8876 8.37 KVM_CAP_S390_PROTECTED_DUMP                 8876 8.37 KVM_CAP_S390_PROTECTED_DUMP
8877 --------------------------------                 8877 --------------------------------
8878                                                  8878 
8879 :Capability: KVM_CAP_S390_PROTECTED_DUMP         8879 :Capability: KVM_CAP_S390_PROTECTED_DUMP
8880 :Architectures: s390                             8880 :Architectures: s390
8881 :Type: vm                                        8881 :Type: vm
8882                                                  8882 
8883 This capability indicates that KVM and the Ul    8883 This capability indicates that KVM and the Ultravisor support dumping
8884 PV guests. The `KVM_PV_DUMP` command is avail    8884 PV guests. The `KVM_PV_DUMP` command is available for the
8885 `KVM_S390_PV_COMMAND` ioctl and the `KVM_PV_I    8885 `KVM_S390_PV_COMMAND` ioctl and the `KVM_PV_INFO` command provides
8886 dump related UV data. Also the vcpu ioctl `KV    8886 dump related UV data. Also the vcpu ioctl `KVM_S390_PV_CPU_COMMAND` is
8887 available and supports the `KVM_PV_DUMP_CPU`     8887 available and supports the `KVM_PV_DUMP_CPU` subcommand.
8888                                                  8888 
8889 8.38 KVM_CAP_VM_DISABLE_NX_HUGE_PAGES            8889 8.38 KVM_CAP_VM_DISABLE_NX_HUGE_PAGES
8890 -------------------------------------            8890 -------------------------------------
8891                                                  8891 
8892 :Capability: KVM_CAP_VM_DISABLE_NX_HUGE_PAGES    8892 :Capability: KVM_CAP_VM_DISABLE_NX_HUGE_PAGES
8893 :Architectures: x86                              8893 :Architectures: x86
8894 :Type: vm                                        8894 :Type: vm
8895 :Parameters: arg[0] must be 0.                   8895 :Parameters: arg[0] must be 0.
8896 :Returns: 0 on success, -EPERM if the userspa    8896 :Returns: 0 on success, -EPERM if the userspace process does not
8897           have CAP_SYS_BOOT, -EINVAL if args[    8897           have CAP_SYS_BOOT, -EINVAL if args[0] is not 0 or any vCPUs have been
8898           created.                               8898           created.
8899                                                  8899 
8900 This capability disables the NX huge pages mi    8900 This capability disables the NX huge pages mitigation for iTLB MULTIHIT.
8901                                                  8901 
8902 The capability has no effect if the nx_huge_p    8902 The capability has no effect if the nx_huge_pages module parameter is not set.
8903                                                  8903 
8904 This capability may only be set before any vC    8904 This capability may only be set before any vCPUs are created.
8905                                                  8905 
8906 8.39 KVM_CAP_S390_CPU_TOPOLOGY                   8906 8.39 KVM_CAP_S390_CPU_TOPOLOGY
8907 ------------------------------                   8907 ------------------------------
8908                                                  8908 
8909 :Capability: KVM_CAP_S390_CPU_TOPOLOGY           8909 :Capability: KVM_CAP_S390_CPU_TOPOLOGY
8910 :Architectures: s390                             8910 :Architectures: s390
8911 :Type: vm                                        8911 :Type: vm
8912                                                  8912 
8913 This capability indicates that KVM will provi    8913 This capability indicates that KVM will provide the S390 CPU Topology
8914 facility which consist of the interpretation     8914 facility which consist of the interpretation of the PTF instruction for
8915 the function code 2 along with interception a    8915 the function code 2 along with interception and forwarding of both the
8916 PTF instruction with function codes 0 or 1 an    8916 PTF instruction with function codes 0 or 1 and the STSI(15,1,x)
8917 instruction to the userland hypervisor.          8917 instruction to the userland hypervisor.
8918                                                  8918 
8919 The stfle facility 11, CPU Topology facility,    8919 The stfle facility 11, CPU Topology facility, should not be indicated
8920 to the guest without this capability.            8920 to the guest without this capability.
8921                                                  8921 
8922 When this capability is present, KVM provides    8922 When this capability is present, KVM provides a new attribute group
8923 on vm fd, KVM_S390_VM_CPU_TOPOLOGY.              8923 on vm fd, KVM_S390_VM_CPU_TOPOLOGY.
8924 This new attribute allows to get, set or clea    8924 This new attribute allows to get, set or clear the Modified Change
8925 Topology Report (MTCR) bit of the SCA through    8925 Topology Report (MTCR) bit of the SCA through the kvm_device_attr
8926 structure.                                       8926 structure.
8927                                                  8927 
8928 When getting the Modified Change Topology Rep    8928 When getting the Modified Change Topology Report value, the attr->addr
8929 must point to a byte where the value will be     8929 must point to a byte where the value will be stored or retrieved from.
8930                                                  8930 
8931 8.40 KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE          8931 8.40 KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE
8932 ---------------------------------------          8932 ---------------------------------------
8933                                                  8933 
8934 :Capability: KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SI    8934 :Capability: KVM_CAP_ARM_EAGER_SPLIT_CHUNK_SIZE
8935 :Architectures: arm64                            8935 :Architectures: arm64
8936 :Type: vm                                        8936 :Type: vm
8937 :Parameters: arg[0] is the new split chunk si    8937 :Parameters: arg[0] is the new split chunk size.
8938 :Returns: 0 on success, -EINVAL if any memslo    8938 :Returns: 0 on success, -EINVAL if any memslot was already created.
8939                                                  8939 
8940 This capability sets the chunk size used in E    8940 This capability sets the chunk size used in Eager Page Splitting.
8941                                                  8941 
8942 Eager Page Splitting improves the performance    8942 Eager Page Splitting improves the performance of dirty-logging (used
8943 in live migrations) when guest memory is back    8943 in live migrations) when guest memory is backed by huge-pages.  It
8944 avoids splitting huge-pages (into PAGE_SIZE p    8944 avoids splitting huge-pages (into PAGE_SIZE pages) on fault, by doing
8945 it eagerly when enabling dirty logging (with     8945 it eagerly when enabling dirty logging (with the
8946 KVM_MEM_LOG_DIRTY_PAGES flag for a memory reg    8946 KVM_MEM_LOG_DIRTY_PAGES flag for a memory region), or when using
8947 KVM_CLEAR_DIRTY_LOG.                             8947 KVM_CLEAR_DIRTY_LOG.
8948                                                  8948 
8949 The chunk size specifies how many pages to br    8949 The chunk size specifies how many pages to break at a time, using a
8950 single allocation for each chunk. Bigger the     8950 single allocation for each chunk. Bigger the chunk size, more pages
8951 need to be allocated ahead of time.              8951 need to be allocated ahead of time.
8952                                                  8952 
8953 The chunk size needs to be a valid block size    8953 The chunk size needs to be a valid block size. The list of acceptable
8954 block sizes is exposed in KVM_CAP_ARM_SUPPORT    8954 block sizes is exposed in KVM_CAP_ARM_SUPPORTED_BLOCK_SIZES as a
8955 64-bit bitmap (each bit describing a block si    8955 64-bit bitmap (each bit describing a block size). The default value is
8956 0, to disable the eager page splitting.          8956 0, to disable the eager page splitting.
8957                                                  8957 
8958 8.41 KVM_CAP_VM_TYPES                            8958 8.41 KVM_CAP_VM_TYPES
8959 ---------------------                            8959 ---------------------
8960                                                  8960 
8961 :Capability: KVM_CAP_MEMORY_ATTRIBUTES           8961 :Capability: KVM_CAP_MEMORY_ATTRIBUTES
8962 :Architectures: x86                              8962 :Architectures: x86
8963 :Type: system ioctl                              8963 :Type: system ioctl
8964                                                  8964 
8965 This capability returns a bitmap of support V    8965 This capability returns a bitmap of support VM types.  The 1-setting of bit @n
8966 means the VM type with value @n is supported.    8966 means the VM type with value @n is supported.  Possible values of @n are::
8967                                                  8967 
8968   #define KVM_X86_DEFAULT_VM    0                8968   #define KVM_X86_DEFAULT_VM    0
8969   #define KVM_X86_SW_PROTECTED_VM       1        8969   #define KVM_X86_SW_PROTECTED_VM       1
8970   #define KVM_X86_SEV_VM        2                8970   #define KVM_X86_SEV_VM        2
8971   #define KVM_X86_SEV_ES_VM     3                8971   #define KVM_X86_SEV_ES_VM     3
8972                                                  8972 
8973 Note, KVM_X86_SW_PROTECTED_VM is currently on    8973 Note, KVM_X86_SW_PROTECTED_VM is currently only for development and testing.
8974 Do not use KVM_X86_SW_PROTECTED_VM for "real"    8974 Do not use KVM_X86_SW_PROTECTED_VM for "real" VMs, and especially not in
8975 production.  The behavior and effective ABI f    8975 production.  The behavior and effective ABI for software-protected VMs is
8976 unstable.                                        8976 unstable.
8977                                                  8977 
8978 9. Known KVM API problems                        8978 9. Known KVM API problems
8979 =========================                        8979 =========================
8980                                                  8980 
8981 In some cases, KVM's API has some inconsisten    8981 In some cases, KVM's API has some inconsistencies or common pitfalls
8982 that userspace need to be aware of.  This sec    8982 that userspace need to be aware of.  This section details some of
8983 these issues.                                    8983 these issues.
8984                                                  8984 
8985 Most of them are architecture specific, so th    8985 Most of them are architecture specific, so the section is split by
8986 architecture.                                    8986 architecture.
8987                                                  8987 
8988 9.1. x86                                         8988 9.1. x86
8989 --------                                         8989 --------
8990                                                  8990 
8991 ``KVM_GET_SUPPORTED_CPUID`` issues               8991 ``KVM_GET_SUPPORTED_CPUID`` issues
8992 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^               8992 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
8993                                                  8993 
8994 In general, ``KVM_GET_SUPPORTED_CPUID`` is de    8994 In general, ``KVM_GET_SUPPORTED_CPUID`` is designed so that it is possible
8995 to take its result and pass it directly to ``    8995 to take its result and pass it directly to ``KVM_SET_CPUID2``.  This section
8996 documents some cases in which that requires s    8996 documents some cases in which that requires some care.
8997                                                  8997 
8998 Local APIC features                              8998 Local APIC features
8999 ~~~~~~~~~~~~~~~~~~~                              8999 ~~~~~~~~~~~~~~~~~~~
9000                                                  9000 
9001 CPU[EAX=1]:ECX[21] (X2APIC) is reported by ``    9001 CPU[EAX=1]:ECX[21] (X2APIC) is reported by ``KVM_GET_SUPPORTED_CPUID``,
9002 but it can only be enabled if ``KVM_CREATE_IR    9002 but it can only be enabled if ``KVM_CREATE_IRQCHIP`` or
9003 ``KVM_ENABLE_CAP(KVM_CAP_IRQCHIP_SPLIT)`` are    9003 ``KVM_ENABLE_CAP(KVM_CAP_IRQCHIP_SPLIT)`` are used to enable in-kernel emulation of
9004 the local APIC.                                  9004 the local APIC.
9005                                                  9005 
9006 The same is true for the ``KVM_FEATURE_PV_UNH    9006 The same is true for the ``KVM_FEATURE_PV_UNHALT`` paravirtualized feature.
9007                                                  9007 
9008 CPU[EAX=1]:ECX[24] (TSC_DEADLINE) is not repo    9008 CPU[EAX=1]:ECX[24] (TSC_DEADLINE) is not reported by ``KVM_GET_SUPPORTED_CPUID``.
9009 It can be enabled if ``KVM_CAP_TSC_DEADLINE_T    9009 It can be enabled if ``KVM_CAP_TSC_DEADLINE_TIMER`` is present and the kernel
9010 has enabled in-kernel emulation of the local     9010 has enabled in-kernel emulation of the local APIC.
9011                                                  9011 
9012 CPU topology                                     9012 CPU topology
9013 ~~~~~~~~~~~~                                     9013 ~~~~~~~~~~~~
9014                                                  9014 
9015 Several CPUID values include topology informa    9015 Several CPUID values include topology information for the host CPU:
9016 0x0b and 0x1f for Intel systems, 0x8000001e f    9016 0x0b and 0x1f for Intel systems, 0x8000001e for AMD systems.  Different
9017 versions of KVM return different values for t    9017 versions of KVM return different values for this information and userspace
9018 should not rely on it.  Currently they return    9018 should not rely on it.  Currently they return all zeroes.
9019                                                  9019 
9020 If userspace wishes to set up a guest topolog    9020 If userspace wishes to set up a guest topology, it should be careful that
9021 the values of these three leaves differ for e    9021 the values of these three leaves differ for each CPU.  In particular,
9022 the APIC ID is found in EDX for all subleaves    9022 the APIC ID is found in EDX for all subleaves of 0x0b and 0x1f, and in EAX
9023 for 0x8000001e; the latter also encodes the c    9023 for 0x8000001e; the latter also encodes the core id and node id in bits
9024 7:0 of EBX and ECX respectively.                 9024 7:0 of EBX and ECX respectively.
9025                                                  9025 
9026 Obsolete ioctls and capabilities                 9026 Obsolete ioctls and capabilities
9027 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^                 9027 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
9028                                                  9028 
9029 KVM_CAP_DISABLE_QUIRKS does not let userspace    9029 KVM_CAP_DISABLE_QUIRKS does not let userspace know which quirks are actually
9030 available.  Use ``KVM_CHECK_EXTENSION(KVM_CAP    9030 available.  Use ``KVM_CHECK_EXTENSION(KVM_CAP_DISABLE_QUIRKS2)`` instead if
9031 available.                                       9031 available.
9032                                                  9032 
9033 Ordering of KVM_GET_*/KVM_SET_* ioctls           9033 Ordering of KVM_GET_*/KVM_SET_* ioctls
9034 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^           9034 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
9035                                                  9035 
9036 TBD                                              9036 TBD
                                                      

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