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TOMOYO Linux Cross Reference
Linux/arch/arm64/kvm/hyp/nvhe/pkvm.c

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  1 // SPDX-License-Identifier: GPL-2.0-only
  2 /*
  3  * Copyright (C) 2021 Google LLC
  4  * Author: Fuad Tabba <tabba@google.com>
  5  */
  6 
  7 #include <linux/kvm_host.h>
  8 #include <linux/mm.h>
  9 #include <nvhe/fixed_config.h>
 10 #include <nvhe/mem_protect.h>
 11 #include <nvhe/memory.h>
 12 #include <nvhe/pkvm.h>
 13 #include <nvhe/trap_handler.h>
 14 
 15 /* Used by icache_is_aliasing(). */
 16 unsigned long __icache_flags;
 17 
 18 /* Used by kvm_get_vttbr(). */
 19 unsigned int kvm_arm_vmid_bits;
 20 
 21 unsigned int kvm_host_sve_max_vl;
 22 
 23 /*
 24  * Set trap register values based on features in ID_AA64PFR0.
 25  */
 26 static void pvm_init_traps_aa64pfr0(struct kvm_vcpu *vcpu)
 27 {
 28         const u64 feature_ids = pvm_read_id_reg(vcpu, SYS_ID_AA64PFR0_EL1);
 29         u64 hcr_set = HCR_RW;
 30         u64 hcr_clear = 0;
 31         u64 cptr_set = 0;
 32         u64 cptr_clear = 0;
 33 
 34         /* Protected KVM does not support AArch32 guests. */
 35         BUILD_BUG_ON(FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_EL0),
 36                 PVM_ID_AA64PFR0_RESTRICT_UNSIGNED) != ID_AA64PFR0_EL1_EL0_IMP);
 37         BUILD_BUG_ON(FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_EL1),
 38                 PVM_ID_AA64PFR0_RESTRICT_UNSIGNED) != ID_AA64PFR0_EL1_EL1_IMP);
 39 
 40         /*
 41          * Linux guests assume support for floating-point and Advanced SIMD. Do
 42          * not change the trapping behavior for these from the KVM default.
 43          */
 44         BUILD_BUG_ON(!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_FP),
 45                                 PVM_ID_AA64PFR0_ALLOW));
 46         BUILD_BUG_ON(!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_AdvSIMD),
 47                                 PVM_ID_AA64PFR0_ALLOW));
 48 
 49         if (has_hvhe())
 50                 hcr_set |= HCR_E2H;
 51 
 52         /* Trap RAS unless all current versions are supported */
 53         if (FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_RAS), feature_ids) <
 54             ID_AA64PFR0_EL1_RAS_V1P1) {
 55                 hcr_set |= HCR_TERR | HCR_TEA;
 56                 hcr_clear |= HCR_FIEN;
 57         }
 58 
 59         /* Trap AMU */
 60         if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_AMU), feature_ids)) {
 61                 hcr_clear |= HCR_AMVOFFEN;
 62                 cptr_set |= CPTR_EL2_TAM;
 63         }
 64 
 65         /* Trap SVE */
 66         if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_SVE), feature_ids)) {
 67                 if (has_hvhe())
 68                         cptr_clear |= CPACR_ELx_ZEN;
 69                 else
 70                         cptr_set |= CPTR_EL2_TZ;
 71         }
 72 
 73         vcpu->arch.hcr_el2 |= hcr_set;
 74         vcpu->arch.hcr_el2 &= ~hcr_clear;
 75         vcpu->arch.cptr_el2 |= cptr_set;
 76         vcpu->arch.cptr_el2 &= ~cptr_clear;
 77 }
 78 
 79 /*
 80  * Set trap register values based on features in ID_AA64PFR1.
 81  */
 82 static void pvm_init_traps_aa64pfr1(struct kvm_vcpu *vcpu)
 83 {
 84         const u64 feature_ids = pvm_read_id_reg(vcpu, SYS_ID_AA64PFR1_EL1);
 85         u64 hcr_set = 0;
 86         u64 hcr_clear = 0;
 87 
 88         /* Memory Tagging: Trap and Treat as Untagged if not supported. */
 89         if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR1_EL1_MTE), feature_ids)) {
 90                 hcr_set |= HCR_TID5;
 91                 hcr_clear |= HCR_DCT | HCR_ATA;
 92         }
 93 
 94         vcpu->arch.hcr_el2 |= hcr_set;
 95         vcpu->arch.hcr_el2 &= ~hcr_clear;
 96 }
 97 
 98 /*
 99  * Set trap register values based on features in ID_AA64DFR0.
100  */
101 static void pvm_init_traps_aa64dfr0(struct kvm_vcpu *vcpu)
102 {
103         const u64 feature_ids = pvm_read_id_reg(vcpu, SYS_ID_AA64DFR0_EL1);
104         u64 mdcr_set = 0;
105         u64 mdcr_clear = 0;
106         u64 cptr_set = 0;
107 
108         /* Trap/constrain PMU */
109         if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer), feature_ids)) {
110                 mdcr_set |= MDCR_EL2_TPM | MDCR_EL2_TPMCR;
111                 mdcr_clear |= MDCR_EL2_HPME | MDCR_EL2_MTPME |
112                               MDCR_EL2_HPMN_MASK;
113         }
114 
115         /* Trap Debug */
116         if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_DebugVer), feature_ids))
117                 mdcr_set |= MDCR_EL2_TDRA | MDCR_EL2_TDA | MDCR_EL2_TDE;
118 
119         /* Trap OS Double Lock */
120         if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_DoubleLock), feature_ids))
121                 mdcr_set |= MDCR_EL2_TDOSA;
122 
123         /* Trap SPE */
124         if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMSVer), feature_ids)) {
125                 mdcr_set |= MDCR_EL2_TPMS;
126                 mdcr_clear |= MDCR_EL2_E2PB_MASK << MDCR_EL2_E2PB_SHIFT;
127         }
128 
129         /* Trap Trace Filter */
130         if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_TraceFilt), feature_ids))
131                 mdcr_set |= MDCR_EL2_TTRF;
132 
133         /* Trap Trace */
134         if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_TraceVer), feature_ids)) {
135                 if (has_hvhe())
136                         cptr_set |= CPACR_EL1_TTA;
137                 else
138                         cptr_set |= CPTR_EL2_TTA;
139         }
140 
141         /* Trap External Trace */
142         if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_ExtTrcBuff), feature_ids))
143                 mdcr_clear |= MDCR_EL2_E2TB_MASK << MDCR_EL2_E2TB_SHIFT;
144 
145         vcpu->arch.mdcr_el2 |= mdcr_set;
146         vcpu->arch.mdcr_el2 &= ~mdcr_clear;
147         vcpu->arch.cptr_el2 |= cptr_set;
148 }
149 
150 /*
151  * Set trap register values based on features in ID_AA64MMFR0.
152  */
153 static void pvm_init_traps_aa64mmfr0(struct kvm_vcpu *vcpu)
154 {
155         const u64 feature_ids = pvm_read_id_reg(vcpu, SYS_ID_AA64MMFR0_EL1);
156         u64 mdcr_set = 0;
157 
158         /* Trap Debug Communications Channel registers */
159         if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64MMFR0_EL1_FGT), feature_ids))
160                 mdcr_set |= MDCR_EL2_TDCC;
161 
162         vcpu->arch.mdcr_el2 |= mdcr_set;
163 }
164 
165 /*
166  * Set trap register values based on features in ID_AA64MMFR1.
167  */
168 static void pvm_init_traps_aa64mmfr1(struct kvm_vcpu *vcpu)
169 {
170         const u64 feature_ids = pvm_read_id_reg(vcpu, SYS_ID_AA64MMFR1_EL1);
171         u64 hcr_set = 0;
172 
173         /* Trap LOR */
174         if (!FIELD_GET(ARM64_FEATURE_MASK(ID_AA64MMFR1_EL1_LO), feature_ids))
175                 hcr_set |= HCR_TLOR;
176 
177         vcpu->arch.hcr_el2 |= hcr_set;
178 }
179 
180 /*
181  * Set baseline trap register values.
182  */
183 static void pvm_init_trap_regs(struct kvm_vcpu *vcpu)
184 {
185         const u64 hcr_trap_feat_regs = HCR_TID3;
186         const u64 hcr_trap_impdef = HCR_TACR | HCR_TIDCP | HCR_TID1;
187 
188         /*
189          * Always trap:
190          * - Feature id registers: to control features exposed to guests
191          * - Implementation-defined features
192          */
193         vcpu->arch.hcr_el2 |= hcr_trap_feat_regs | hcr_trap_impdef;
194 
195         /* Clear res0 and set res1 bits to trap potential new features. */
196         vcpu->arch.hcr_el2 &= ~(HCR_RES0);
197         vcpu->arch.mdcr_el2 &= ~(MDCR_EL2_RES0);
198         if (!has_hvhe()) {
199                 vcpu->arch.cptr_el2 |= CPTR_NVHE_EL2_RES1;
200                 vcpu->arch.cptr_el2 &= ~(CPTR_NVHE_EL2_RES0);
201         }
202 }
203 
204 /*
205  * Initialize trap register values in protected mode.
206  */
207 void __pkvm_vcpu_init_traps(struct kvm_vcpu *vcpu)
208 {
209         pvm_init_trap_regs(vcpu);
210         pvm_init_traps_aa64pfr0(vcpu);
211         pvm_init_traps_aa64pfr1(vcpu);
212         pvm_init_traps_aa64dfr0(vcpu);
213         pvm_init_traps_aa64mmfr0(vcpu);
214         pvm_init_traps_aa64mmfr1(vcpu);
215 }
216 
217 /*
218  * Start the VM table handle at the offset defined instead of at 0.
219  * Mainly for sanity checking and debugging.
220  */
221 #define HANDLE_OFFSET 0x1000
222 
223 static unsigned int vm_handle_to_idx(pkvm_handle_t handle)
224 {
225         return handle - HANDLE_OFFSET;
226 }
227 
228 static pkvm_handle_t idx_to_vm_handle(unsigned int idx)
229 {
230         return idx + HANDLE_OFFSET;
231 }
232 
233 /*
234  * Spinlock for protecting state related to the VM table. Protects writes
235  * to 'vm_table' and 'nr_table_entries' as well as reads and writes to
236  * 'last_hyp_vcpu_lookup'.
237  */
238 static DEFINE_HYP_SPINLOCK(vm_table_lock);
239 
240 /*
241  * The table of VM entries for protected VMs in hyp.
242  * Allocated at hyp initialization and setup.
243  */
244 static struct pkvm_hyp_vm **vm_table;
245 
246 void pkvm_hyp_vm_table_init(void *tbl)
247 {
248         WARN_ON(vm_table);
249         vm_table = tbl;
250 }
251 
252 /*
253  * Return the hyp vm structure corresponding to the handle.
254  */
255 static struct pkvm_hyp_vm *get_vm_by_handle(pkvm_handle_t handle)
256 {
257         unsigned int idx = vm_handle_to_idx(handle);
258 
259         if (unlikely(idx >= KVM_MAX_PVMS))
260                 return NULL;
261 
262         return vm_table[idx];
263 }
264 
265 struct pkvm_hyp_vcpu *pkvm_load_hyp_vcpu(pkvm_handle_t handle,
266                                          unsigned int vcpu_idx)
267 {
268         struct pkvm_hyp_vcpu *hyp_vcpu = NULL;
269         struct pkvm_hyp_vm *hyp_vm;
270 
271         hyp_spin_lock(&vm_table_lock);
272         hyp_vm = get_vm_by_handle(handle);
273         if (!hyp_vm || hyp_vm->nr_vcpus <= vcpu_idx)
274                 goto unlock;
275 
276         hyp_vcpu = hyp_vm->vcpus[vcpu_idx];
277         hyp_page_ref_inc(hyp_virt_to_page(hyp_vm));
278 unlock:
279         hyp_spin_unlock(&vm_table_lock);
280         return hyp_vcpu;
281 }
282 
283 void pkvm_put_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu)
284 {
285         struct pkvm_hyp_vm *hyp_vm = pkvm_hyp_vcpu_to_hyp_vm(hyp_vcpu);
286 
287         hyp_spin_lock(&vm_table_lock);
288         hyp_page_ref_dec(hyp_virt_to_page(hyp_vm));
289         hyp_spin_unlock(&vm_table_lock);
290 }
291 
292 static void unpin_host_vcpu(struct kvm_vcpu *host_vcpu)
293 {
294         if (host_vcpu)
295                 hyp_unpin_shared_mem(host_vcpu, host_vcpu + 1);
296 }
297 
298 static void unpin_host_vcpus(struct pkvm_hyp_vcpu *hyp_vcpus[],
299                              unsigned int nr_vcpus)
300 {
301         int i;
302 
303         for (i = 0; i < nr_vcpus; i++)
304                 unpin_host_vcpu(hyp_vcpus[i]->host_vcpu);
305 }
306 
307 static void init_pkvm_hyp_vm(struct kvm *host_kvm, struct pkvm_hyp_vm *hyp_vm,
308                              unsigned int nr_vcpus)
309 {
310         hyp_vm->host_kvm = host_kvm;
311         hyp_vm->kvm.created_vcpus = nr_vcpus;
312         hyp_vm->kvm.arch.mmu.vtcr = host_mmu.arch.mmu.vtcr;
313 }
314 
315 static int init_pkvm_hyp_vcpu(struct pkvm_hyp_vcpu *hyp_vcpu,
316                               struct pkvm_hyp_vm *hyp_vm,
317                               struct kvm_vcpu *host_vcpu,
318                               unsigned int vcpu_idx)
319 {
320         int ret = 0;
321 
322         if (hyp_pin_shared_mem(host_vcpu, host_vcpu + 1))
323                 return -EBUSY;
324 
325         if (host_vcpu->vcpu_idx != vcpu_idx) {
326                 ret = -EINVAL;
327                 goto done;
328         }
329 
330         hyp_vcpu->host_vcpu = host_vcpu;
331 
332         hyp_vcpu->vcpu.kvm = &hyp_vm->kvm;
333         hyp_vcpu->vcpu.vcpu_id = READ_ONCE(host_vcpu->vcpu_id);
334         hyp_vcpu->vcpu.vcpu_idx = vcpu_idx;
335 
336         hyp_vcpu->vcpu.arch.hw_mmu = &hyp_vm->kvm.arch.mmu;
337         hyp_vcpu->vcpu.arch.cflags = READ_ONCE(host_vcpu->arch.cflags);
338 done:
339         if (ret)
340                 unpin_host_vcpu(host_vcpu);
341         return ret;
342 }
343 
344 static int find_free_vm_table_entry(struct kvm *host_kvm)
345 {
346         int i;
347 
348         for (i = 0; i < KVM_MAX_PVMS; ++i) {
349                 if (!vm_table[i])
350                         return i;
351         }
352 
353         return -ENOMEM;
354 }
355 
356 /*
357  * Allocate a VM table entry and insert a pointer to the new vm.
358  *
359  * Return a unique handle to the protected VM on success,
360  * negative error code on failure.
361  */
362 static pkvm_handle_t insert_vm_table_entry(struct kvm *host_kvm,
363                                            struct pkvm_hyp_vm *hyp_vm)
364 {
365         struct kvm_s2_mmu *mmu = &hyp_vm->kvm.arch.mmu;
366         int idx;
367 
368         hyp_assert_lock_held(&vm_table_lock);
369 
370         /*
371          * Initializing protected state might have failed, yet a malicious
372          * host could trigger this function. Thus, ensure that 'vm_table'
373          * exists.
374          */
375         if (unlikely(!vm_table))
376                 return -EINVAL;
377 
378         idx = find_free_vm_table_entry(host_kvm);
379         if (idx < 0)
380                 return idx;
381 
382         hyp_vm->kvm.arch.pkvm.handle = idx_to_vm_handle(idx);
383 
384         /* VMID 0 is reserved for the host */
385         atomic64_set(&mmu->vmid.id, idx + 1);
386 
387         mmu->arch = &hyp_vm->kvm.arch;
388         mmu->pgt = &hyp_vm->pgt;
389 
390         vm_table[idx] = hyp_vm;
391         return hyp_vm->kvm.arch.pkvm.handle;
392 }
393 
394 /*
395  * Deallocate and remove the VM table entry corresponding to the handle.
396  */
397 static void remove_vm_table_entry(pkvm_handle_t handle)
398 {
399         hyp_assert_lock_held(&vm_table_lock);
400         vm_table[vm_handle_to_idx(handle)] = NULL;
401 }
402 
403 static size_t pkvm_get_hyp_vm_size(unsigned int nr_vcpus)
404 {
405         return size_add(sizeof(struct pkvm_hyp_vm),
406                 size_mul(sizeof(struct pkvm_hyp_vcpu *), nr_vcpus));
407 }
408 
409 static void *map_donated_memory_noclear(unsigned long host_va, size_t size)
410 {
411         void *va = (void *)kern_hyp_va(host_va);
412 
413         if (!PAGE_ALIGNED(va))
414                 return NULL;
415 
416         if (__pkvm_host_donate_hyp(hyp_virt_to_pfn(va),
417                                    PAGE_ALIGN(size) >> PAGE_SHIFT))
418                 return NULL;
419 
420         return va;
421 }
422 
423 static void *map_donated_memory(unsigned long host_va, size_t size)
424 {
425         void *va = map_donated_memory_noclear(host_va, size);
426 
427         if (va)
428                 memset(va, 0, size);
429 
430         return va;
431 }
432 
433 static void __unmap_donated_memory(void *va, size_t size)
434 {
435         kvm_flush_dcache_to_poc(va, size);
436         WARN_ON(__pkvm_hyp_donate_host(hyp_virt_to_pfn(va),
437                                        PAGE_ALIGN(size) >> PAGE_SHIFT));
438 }
439 
440 static void unmap_donated_memory(void *va, size_t size)
441 {
442         if (!va)
443                 return;
444 
445         memset(va, 0, size);
446         __unmap_donated_memory(va, size);
447 }
448 
449 static void unmap_donated_memory_noclear(void *va, size_t size)
450 {
451         if (!va)
452                 return;
453 
454         __unmap_donated_memory(va, size);
455 }
456 
457 /*
458  * Initialize the hypervisor copy of the protected VM state using the
459  * memory donated by the host.
460  *
461  * Unmaps the donated memory from the host at stage 2.
462  *
463  * host_kvm: A pointer to the host's struct kvm.
464  * vm_hva: The host va of the area being donated for the VM state.
465  *         Must be page aligned.
466  * pgd_hva: The host va of the area being donated for the stage-2 PGD for
467  *          the VM. Must be page aligned. Its size is implied by the VM's
468  *          VTCR.
469  *
470  * Return a unique handle to the protected VM on success,
471  * negative error code on failure.
472  */
473 int __pkvm_init_vm(struct kvm *host_kvm, unsigned long vm_hva,
474                    unsigned long pgd_hva)
475 {
476         struct pkvm_hyp_vm *hyp_vm = NULL;
477         size_t vm_size, pgd_size;
478         unsigned int nr_vcpus;
479         void *pgd = NULL;
480         int ret;
481 
482         ret = hyp_pin_shared_mem(host_kvm, host_kvm + 1);
483         if (ret)
484                 return ret;
485 
486         nr_vcpus = READ_ONCE(host_kvm->created_vcpus);
487         if (nr_vcpus < 1) {
488                 ret = -EINVAL;
489                 goto err_unpin_kvm;
490         }
491 
492         vm_size = pkvm_get_hyp_vm_size(nr_vcpus);
493         pgd_size = kvm_pgtable_stage2_pgd_size(host_mmu.arch.mmu.vtcr);
494 
495         ret = -ENOMEM;
496 
497         hyp_vm = map_donated_memory(vm_hva, vm_size);
498         if (!hyp_vm)
499                 goto err_remove_mappings;
500 
501         pgd = map_donated_memory_noclear(pgd_hva, pgd_size);
502         if (!pgd)
503                 goto err_remove_mappings;
504 
505         init_pkvm_hyp_vm(host_kvm, hyp_vm, nr_vcpus);
506 
507         hyp_spin_lock(&vm_table_lock);
508         ret = insert_vm_table_entry(host_kvm, hyp_vm);
509         if (ret < 0)
510                 goto err_unlock;
511 
512         ret = kvm_guest_prepare_stage2(hyp_vm, pgd);
513         if (ret)
514                 goto err_remove_vm_table_entry;
515         hyp_spin_unlock(&vm_table_lock);
516 
517         return hyp_vm->kvm.arch.pkvm.handle;
518 
519 err_remove_vm_table_entry:
520         remove_vm_table_entry(hyp_vm->kvm.arch.pkvm.handle);
521 err_unlock:
522         hyp_spin_unlock(&vm_table_lock);
523 err_remove_mappings:
524         unmap_donated_memory(hyp_vm, vm_size);
525         unmap_donated_memory(pgd, pgd_size);
526 err_unpin_kvm:
527         hyp_unpin_shared_mem(host_kvm, host_kvm + 1);
528         return ret;
529 }
530 
531 /*
532  * Initialize the hypervisor copy of the protected vCPU state using the
533  * memory donated by the host.
534  *
535  * handle: The handle for the protected vm.
536  * host_vcpu: A pointer to the corresponding host vcpu.
537  * vcpu_hva: The host va of the area being donated for the vcpu state.
538  *           Must be page aligned. The size of the area must be equal to
539  *           the page-aligned size of 'struct pkvm_hyp_vcpu'.
540  * Return 0 on success, negative error code on failure.
541  */
542 int __pkvm_init_vcpu(pkvm_handle_t handle, struct kvm_vcpu *host_vcpu,
543                      unsigned long vcpu_hva)
544 {
545         struct pkvm_hyp_vcpu *hyp_vcpu;
546         struct pkvm_hyp_vm *hyp_vm;
547         unsigned int idx;
548         int ret;
549 
550         hyp_vcpu = map_donated_memory(vcpu_hva, sizeof(*hyp_vcpu));
551         if (!hyp_vcpu)
552                 return -ENOMEM;
553 
554         hyp_spin_lock(&vm_table_lock);
555 
556         hyp_vm = get_vm_by_handle(handle);
557         if (!hyp_vm) {
558                 ret = -ENOENT;
559                 goto unlock;
560         }
561 
562         idx = hyp_vm->nr_vcpus;
563         if (idx >= hyp_vm->kvm.created_vcpus) {
564                 ret = -EINVAL;
565                 goto unlock;
566         }
567 
568         ret = init_pkvm_hyp_vcpu(hyp_vcpu, hyp_vm, host_vcpu, idx);
569         if (ret)
570                 goto unlock;
571 
572         hyp_vm->vcpus[idx] = hyp_vcpu;
573         hyp_vm->nr_vcpus++;
574 unlock:
575         hyp_spin_unlock(&vm_table_lock);
576 
577         if (ret)
578                 unmap_donated_memory(hyp_vcpu, sizeof(*hyp_vcpu));
579 
580         hyp_vcpu->vcpu.arch.cptr_el2 = kvm_get_reset_cptr_el2(&hyp_vcpu->vcpu);
581 
582         return ret;
583 }
584 
585 static void
586 teardown_donated_memory(struct kvm_hyp_memcache *mc, void *addr, size_t size)
587 {
588         size = PAGE_ALIGN(size);
589         memset(addr, 0, size);
590 
591         for (void *start = addr; start < addr + size; start += PAGE_SIZE)
592                 push_hyp_memcache(mc, start, hyp_virt_to_phys);
593 
594         unmap_donated_memory_noclear(addr, size);
595 }
596 
597 int __pkvm_teardown_vm(pkvm_handle_t handle)
598 {
599         struct kvm_hyp_memcache *mc;
600         struct pkvm_hyp_vm *hyp_vm;
601         struct kvm *host_kvm;
602         unsigned int idx;
603         size_t vm_size;
604         int err;
605 
606         hyp_spin_lock(&vm_table_lock);
607         hyp_vm = get_vm_by_handle(handle);
608         if (!hyp_vm) {
609                 err = -ENOENT;
610                 goto err_unlock;
611         }
612 
613         if (WARN_ON(hyp_page_count(hyp_vm))) {
614                 err = -EBUSY;
615                 goto err_unlock;
616         }
617 
618         host_kvm = hyp_vm->host_kvm;
619 
620         /* Ensure the VMID is clean before it can be reallocated */
621         __kvm_tlb_flush_vmid(&hyp_vm->kvm.arch.mmu);
622         remove_vm_table_entry(handle);
623         hyp_spin_unlock(&vm_table_lock);
624 
625         /* Reclaim guest pages (including page-table pages) */
626         mc = &host_kvm->arch.pkvm.teardown_mc;
627         reclaim_guest_pages(hyp_vm, mc);
628         unpin_host_vcpus(hyp_vm->vcpus, hyp_vm->nr_vcpus);
629 
630         /* Push the metadata pages to the teardown memcache */
631         for (idx = 0; idx < hyp_vm->nr_vcpus; ++idx) {
632                 struct pkvm_hyp_vcpu *hyp_vcpu = hyp_vm->vcpus[idx];
633 
634                 teardown_donated_memory(mc, hyp_vcpu, sizeof(*hyp_vcpu));
635         }
636 
637         vm_size = pkvm_get_hyp_vm_size(hyp_vm->kvm.created_vcpus);
638         teardown_donated_memory(mc, hyp_vm, vm_size);
639         hyp_unpin_shared_mem(host_kvm, host_kvm + 1);
640         return 0;
641 
642 err_unlock:
643         hyp_spin_unlock(&vm_table_lock);
644         return err;
645 }
646 

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