1 # SPDX-License-Identifier: GPL-2.0
2
3 config EARLY_PRINTK_USB
4 bool
5
6 config X86_VERBOSE_BOOTUP
7 bool "Enable verbose x86 bootup info m
8 default y
9 help
10 Enables the informational output fro
11 (e.g. bzImage) of the boot. If you d
12 see errors. Disable this if you want
13
14 config EARLY_PRINTK
15 bool "Early printk" if EXPERT
16 default y
17 help
18 Write kernel log output directly int
19 port.
20
21 This is useful for kernel debugging
22 early before the console code is ini
23 it is not recommended because it loo
24 with klogd/syslogd or the X server.
25 unless you want to debug such a cras
26
27 config EARLY_PRINTK_DBGP
28 bool "Early printk via EHCI debug port
29 depends on EARLY_PRINTK && PCI
30 select EARLY_PRINTK_USB
31 help
32 Write kernel log output directly int
33
34 This is useful for kernel debugging
35 early before the console code is ini
36 it is not recommended because it loo
37 with klogd/syslogd or the X server.
38 unless you want to debug such a cras
39
40 config EARLY_PRINTK_USB_XDBC
41 bool "Early printk via the xHCI debug
42 depends on EARLY_PRINTK && PCI
43 select EARLY_PRINTK_USB
44 help
45 Write kernel log output directly int
46
47 One use for this feature is kernel d
48 machine crashes very early before th
49 initialized. Other uses include simp
50 a full-blown printk console driver +
51
52 For normal production environments t
53 because it doesn't feed events into
54 print anything on the screen.
55
56 You should normally say N here, unle
57 crashes or need a very simple printk
58
59 config EFI_PGT_DUMP
60 bool "Dump the EFI pagetable"
61 depends on EFI
62 select PTDUMP_CORE
63 help
64 Enable this if you want to dump the
65 enabling virtual mode. This can be u
66 issues with the mapping of the EFI r
67 table.
68
69 config DEBUG_TLBFLUSH
70 bool "Set upper limit of TLB entries t
71 depends on DEBUG_KERNEL
72 help
73 X86-only for now.
74
75 This option allows the user to tune
76 kernel flushes one-by-one instead of
77 certain situations, the former is ch
78 tlb_flushall_shift knob under /sys/k
79 to -1, the code flushes the whole TL
80 for positive values of it, the kerne
81 invalidating instructions according
82
83 flush_entries <= active_tlb_entries
84
85 If in doubt, say "N".
86
87 config IOMMU_DEBUG
88 bool "Enable IOMMU debugging"
89 depends on GART_IOMMU && DEBUG_KERNEL
90 depends on X86_64
91 help
92 Force the IOMMU to on even when you
93 memory and add debugging code. On ov
94 allow to enable IOMMU leak tracing.
95 time with iommu=noforce. This will a
96 list merging. Currently not recomme
97 code. When you use it make sure you
98 IOMMU/AGP aperture. Most of the opt
99 be set more finegrained using the io
100 options. See Documentation/arch/x86/
101 details.
102
103 config IOMMU_LEAK
104 bool "IOMMU leak tracing"
105 depends on IOMMU_DEBUG && DMA_API_DEBU
106 help
107 Add a simple leak tracer to the IOMM
108 are debugging a buggy device driver
109
110 config HAVE_MMIOTRACE_SUPPORT
111 def_bool y
112
113 config X86_DECODER_SELFTEST
114 bool "x86 instruction decoder selftest
115 depends on DEBUG_KERNEL && INSTRUCTION
116 depends on !COMPILE_TEST
117 help
118 Perform x86 instruction decoder self
119 This option is useful for checking t
120 decoder code.
121 If unsure, say "N".
122
123 choice
124 prompt "IO delay type"
125 default IO_DELAY_0X80
126
127 config IO_DELAY_0X80
128 bool "port 0x80 based port-IO delay [r
129 help
130 This is the traditional Linux IO del
131 It is the most tested hence safest s
132
133 config IO_DELAY_0XED
134 bool "port 0xed based port-IO delay"
135 help
136 Use port 0xed as the IO delay. This
137 often used as a hardware-debug port.
138
139 config IO_DELAY_UDELAY
140 bool "udelay based port-IO delay"
141 help
142 Use udelay(2) as the IO delay method
143 while not having any side-effect on
144
145 config IO_DELAY_NONE
146 bool "no port-IO delay"
147 help
148 No port-IO delay. Will break on old
149 delay for certain operations. Should
150
151 endchoice
152
153 config DEBUG_BOOT_PARAMS
154 bool "Debug boot parameters"
155 depends on DEBUG_KERNEL
156 depends on DEBUG_FS
157 help
158 This option will cause struct boot_p
159
160 config CPA_DEBUG
161 bool "CPA self-test code"
162 depends on DEBUG_KERNEL
163 help
164 Do change_page_attr() self-tests eve
165
166 config DEBUG_ENTRY
167 bool "Debug low-level entry code"
168 depends on DEBUG_KERNEL
169 help
170 This option enables sanity checks in
171 Some of these sanity checks may slow
172 exits or otherwise impact performanc
173
174 If unsure, say N.
175
176 config DEBUG_NMI_SELFTEST
177 bool "NMI Selftest"
178 depends on DEBUG_KERNEL && X86_LOCAL_A
179 help
180 Enabling this option turns on a quic
181 that the NMI behaves correctly.
182
183 This might help diagnose strange han
184 function properly.
185
186 If unsure, say N.
187
188 config DEBUG_IMR_SELFTEST
189 bool "Isolated Memory Region self test
190 depends on INTEL_IMR
191 help
192 This option enables automated sanity
193 Some simple tests are run to verify
194 and overlapping. This option is real
195 debugging an IMR memory map or are m
196 test your changes.
197
198 If unsure say N here.
199
200 config X86_DEBUG_FPU
201 bool "Debug the x86 FPU code"
202 depends on DEBUG_KERNEL
203 default y
204 help
205 If this option is enabled then there
206 checks and (boot time) debug printou
207 This debugging adds some small amoun
208 to the kernel.
209
210 If unsure, say N.
211
212 config PUNIT_ATOM_DEBUG
213 tristate "ATOM Punit debug driver"
214 depends on PCI
215 select DEBUG_FS
216 select IOSF_MBI
217 help
218 This is a debug driver, which gets t
219 of all Punit North Complex devices.
220 each device is exposed as part of th
221 The current power state can be read
222 /sys/kernel/debug/punit_atom/dev_pow
223
224 choice
225 prompt "Choose kernel unwinder"
226 default UNWINDER_ORC if X86_64
227 default UNWINDER_FRAME_POINTER if X86_
228 help
229 This determines which method will be
230 traces for panics, oopses, bugs, war
231 livepatch, lockdep, and more.
232
233 config UNWINDER_ORC
234 bool "ORC unwinder"
235 depends on X86_64
236 select OBJTOOL
237 help
238 This option enables the ORC (Oops Re
239 unwinding kernel stack traces. It u
240 a simplified version of the DWARF Ca
241
242 This unwinder is more accurate acros
243 frame pointer unwinder. It also ena
244 improvement across the entire kernel
245
246 Enabling this option will increase t
247 by roughly 2-4MB, depending on your
248
249 config UNWINDER_FRAME_POINTER
250 bool "Frame pointer unwinder"
251 select ARCH_WANT_FRAME_POINTERS
252 select FRAME_POINTER
253 help
254 This option enables the frame pointe
255 stack traces.
256
257 The unwinder itself is fast and it u
258 unwinder, but the kernel text size w
259 overall performance will degrade by
260
261 config UNWINDER_GUESS
262 bool "Guess unwinder"
263 depends on EXPERT
264 depends on !STACKDEPOT
265 help
266 This option enables the "guess" unwi
267 traces. It scans the stack and repo
268 finds. Some of the addresses it rep
269
270 While this option often produces fal
271 useful in many cases. Unlike the ot
272 overhead.
273
274 endchoice
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