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ec8f24b7 | 1 | # SPDX-License-Identifier: GPL-2.0-only |
06ec64b8 CH |
2 | menu "Kernel hacking" |
3 | ||
604ff0dc | 4 | menu "printk and dmesg options" |
1da177e4 LT |
5 | |
6 | config PRINTK_TIME | |
7 | bool "Show timing information on printks" | |
d3b8b6e5 | 8 | depends on PRINTK |
1da177e4 | 9 | help |
649e6ee3 KS |
10 | Selecting this option causes time stamps of the printk() |
11 | messages to be added to the output of the syslog() system | |
12 | call and at the console. | |
13 | ||
14 | The timestamp is always recorded internally, and exported | |
15 | to /dev/kmsg. This flag just specifies if the timestamp should | |
16 | be included, not that the timestamp is recorded. | |
17 | ||
18 | The behavior is also controlled by the kernel command line | |
8c27ceff | 19 | parameter printk.time=1. See Documentation/admin-guide/kernel-parameters.rst |
1da177e4 | 20 | |
15ff2069 TH |
21 | config PRINTK_CALLER |
22 | bool "Show caller information on printks" | |
23 | depends on PRINTK | |
24 | help | |
25 | Selecting this option causes printk() to add a caller "thread id" (if | |
26 | in task context) or a caller "processor id" (if not in task context) | |
27 | to every message. | |
28 | ||
29 | This option is intended for environments where multiple threads | |
30 | concurrently call printk() for many times, for it is difficult to | |
31 | interpret without knowing where these lines (or sometimes individual | |
32 | line which was divided into multiple lines due to race) came from. | |
33 | ||
34 | Since toggling after boot makes the code racy, currently there is | |
35 | no option to enable/disable at the kernel command line parameter or | |
36 | sysfs interface. | |
37 | ||
22f4e66d SB |
38 | config STACKTRACE_BUILD_ID |
39 | bool "Show build ID information in stacktraces" | |
40 | depends on PRINTK | |
41 | help | |
42 | Selecting this option adds build ID information for symbols in | |
43 | stacktraces printed with the printk format '%p[SR]b'. | |
44 | ||
45 | This option is intended for distros where debuginfo is not easily | |
46 | accessible but can be downloaded given the build ID of the vmlinux or | |
47 | kernel module where the function is located. | |
48 | ||
a8cfdc68 OJ |
49 | config CONSOLE_LOGLEVEL_DEFAULT |
50 | int "Default console loglevel (1-15)" | |
51 | range 1 15 | |
52 | default "7" | |
53 | help | |
54 | Default loglevel to determine what will be printed on the console. | |
55 | ||
56 | Setting a default here is equivalent to passing in loglevel=<x> in | |
57 | the kernel bootargs. loglevel=<x> continues to override whatever | |
58 | value is specified here as well. | |
59 | ||
50f4d9bd | 60 | Note: This does not affect the log level of un-prefixed printk() |
a8cfdc68 OJ |
61 | usage in the kernel. That is controlled by the MESSAGE_LOGLEVEL_DEFAULT |
62 | option. | |
63 | ||
22eceb8b HG |
64 | config CONSOLE_LOGLEVEL_QUIET |
65 | int "quiet console loglevel (1-15)" | |
66 | range 1 15 | |
67 | default "4" | |
68 | help | |
69 | loglevel to use when "quiet" is passed on the kernel commandline. | |
70 | ||
71 | When "quiet" is passed on the kernel commandline this loglevel | |
72 | will be used as the loglevel. IOW passing "quiet" will be the | |
73 | equivalent of passing "loglevel=<CONSOLE_LOGLEVEL_QUIET>" | |
74 | ||
42a9dc0b | 75 | config MESSAGE_LOGLEVEL_DEFAULT |
5af5bcb8 MSB |
76 | int "Default message log level (1-7)" |
77 | range 1 7 | |
78 | default "4" | |
79 | help | |
80 | Default log level for printk statements with no specified priority. | |
81 | ||
82 | This was hard-coded to KERN_WARNING since at least 2.6.10 but folks | |
83 | that are auditing their logs closely may want to set it to a lower | |
84 | priority. | |
85 | ||
a8cfdc68 OJ |
86 | Note: This does not affect what message level gets printed on the console |
87 | by default. To change that, use loglevel=<x> in the kernel bootargs, | |
88 | or pick a different CONSOLE_LOGLEVEL_DEFAULT configuration value. | |
89 | ||
604ff0dc DH |
90 | config BOOT_PRINTK_DELAY |
91 | bool "Delay each boot printk message by N milliseconds" | |
92 | depends on DEBUG_KERNEL && PRINTK && GENERIC_CALIBRATE_DELAY | |
93 | help | |
94 | This build option allows you to read kernel boot messages | |
95 | by inserting a short delay after each one. The delay is | |
96 | specified in milliseconds on the kernel command line, | |
97 | using "boot_delay=N". | |
98 | ||
99 | It is likely that you would also need to use "lpj=M" to preset | |
100 | the "loops per jiffie" value. | |
101 | See a previous boot log for the "lpj" value to use for your | |
102 | system, and then set "lpj=M" before setting "boot_delay=N". | |
103 | NOTE: Using this option may adversely affect SMP systems. | |
104 | I.e., processors other than the first one may not boot up. | |
105 | BOOT_PRINTK_DELAY also may cause LOCKUP_DETECTOR to detect | |
106 | what it believes to be lockup conditions. | |
107 | ||
108 | config DYNAMIC_DEBUG | |
109 | bool "Enable dynamic printk() support" | |
110 | default n | |
111 | depends on PRINTK | |
239a5791 | 112 | depends on (DEBUG_FS || PROC_FS) |
ceabef7d | 113 | select DYNAMIC_DEBUG_CORE |
604ff0dc DH |
114 | help |
115 | ||
116 | Compiles debug level messages into the kernel, which would not | |
117 | otherwise be available at runtime. These messages can then be | |
118 | enabled/disabled based on various levels of scope - per source file, | |
119 | function, module, format string, and line number. This mechanism | |
120 | implicitly compiles in all pr_debug() and dev_dbg() calls, which | |
121 | enlarges the kernel text size by about 2%. | |
122 | ||
123 | If a source file is compiled with DEBUG flag set, any | |
124 | pr_debug() calls in it are enabled by default, but can be | |
125 | disabled at runtime as below. Note that DEBUG flag is | |
126 | turned on by many CONFIG_*DEBUG* options. | |
127 | ||
128 | Usage: | |
129 | ||
130 | Dynamic debugging is controlled via the 'dynamic_debug/control' file, | |
239a5791 GKH |
131 | which is contained in the 'debugfs' filesystem or procfs. |
132 | Thus, the debugfs or procfs filesystem must first be mounted before | |
133 | making use of this feature. | |
604ff0dc DH |
134 | We refer the control file as: <debugfs>/dynamic_debug/control. This |
135 | file contains a list of the debug statements that can be enabled. The | |
136 | format for each line of the file is: | |
137 | ||
138 | filename:lineno [module]function flags format | |
139 | ||
140 | filename : source file of the debug statement | |
141 | lineno : line number of the debug statement | |
142 | module : module that contains the debug statement | |
143 | function : function that contains the debug statement | |
68d4b3df KK |
144 | flags : '=p' means the line is turned 'on' for printing |
145 | format : the format used for the debug statement | |
604ff0dc DH |
146 | |
147 | From a live system: | |
148 | ||
149 | nullarbor:~ # cat <debugfs>/dynamic_debug/control | |
150 | # filename:lineno [module]function flags format | |
151 | fs/aio.c:222 [aio]__put_ioctx =_ "__put_ioctx:\040freeing\040%p\012" | |
152 | fs/aio.c:248 [aio]ioctx_alloc =_ "ENOMEM:\040nr_events\040too\040high\012" | |
153 | fs/aio.c:1770 [aio]sys_io_cancel =_ "calling\040cancel\012" | |
154 | ||
155 | Example usage: | |
156 | ||
157 | // enable the message at line 1603 of file svcsock.c | |
158 | nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > | |
159 | <debugfs>/dynamic_debug/control | |
160 | ||
161 | // enable all the messages in file svcsock.c | |
162 | nullarbor:~ # echo -n 'file svcsock.c +p' > | |
163 | <debugfs>/dynamic_debug/control | |
164 | ||
165 | // enable all the messages in the NFS server module | |
166 | nullarbor:~ # echo -n 'module nfsd +p' > | |
167 | <debugfs>/dynamic_debug/control | |
168 | ||
169 | // enable all 12 messages in the function svc_process() | |
170 | nullarbor:~ # echo -n 'func svc_process +p' > | |
171 | <debugfs>/dynamic_debug/control | |
172 | ||
173 | // disable all 12 messages in the function svc_process() | |
174 | nullarbor:~ # echo -n 'func svc_process -p' > | |
175 | <debugfs>/dynamic_debug/control | |
176 | ||
f8998c22 HH |
177 | See Documentation/admin-guide/dynamic-debug-howto.rst for additional |
178 | information. | |
604ff0dc | 179 | |
ceabef7d OZ |
180 | config DYNAMIC_DEBUG_CORE |
181 | bool "Enable core function of dynamic debug support" | |
182 | depends on PRINTK | |
183 | depends on (DEBUG_FS || PROC_FS) | |
184 | help | |
185 | Enable core functional support of dynamic debug. It is useful | |
186 | when you want to tie dynamic debug to your kernel modules with | |
187 | DYNAMIC_DEBUG_MODULE defined for each of them, especially for | |
188 | the case of embedded system where the kernel image size is | |
189 | sensitive for people. | |
190 | ||
57f5677e RV |
191 | config SYMBOLIC_ERRNAME |
192 | bool "Support symbolic error names in printf" | |
193 | default y if PRINTK | |
194 | help | |
195 | If you say Y here, the kernel's printf implementation will | |
196 | be able to print symbolic error names such as ENOSPC instead | |
197 | of the number 28. It makes the kernel image slightly larger | |
198 | (about 3KB), but can make the kernel logs easier to read. | |
199 | ||
2b05bb75 CD |
200 | config DEBUG_BUGVERBOSE |
201 | bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT | |
202 | depends on BUG && (GENERIC_BUG || HAVE_DEBUG_BUGVERBOSE) | |
203 | default y | |
204 | help | |
205 | Say Y here to make BUG() panics output the file name and line number | |
206 | of the BUG call as well as the EIP and oops trace. This aids | |
207 | debugging but costs about 70-100K of memory. | |
208 | ||
604ff0dc DH |
209 | endmenu # "printk and dmesg options" |
210 | ||
f9b3cd24 KC |
211 | config DEBUG_KERNEL |
212 | bool "Kernel debugging" | |
213 | help | |
214 | Say Y here if you are developing drivers or trying to debug and | |
215 | identify kernel problems. | |
216 | ||
217 | config DEBUG_MISC | |
218 | bool "Miscellaneous debug code" | |
219 | default DEBUG_KERNEL | |
220 | depends on DEBUG_KERNEL | |
221 | help | |
222 | Say Y here if you need to enable miscellaneous debug code that should | |
223 | be under a more specific debug option but isn't. | |
224 | ||
6dfc0665 DH |
225 | menu "Compile-time checks and compiler options" |
226 | ||
227 | config DEBUG_INFO | |
f9b3cd24 | 228 | bool |
6dfc0665 | 229 | help |
f9b3cd24 KC |
230 | A kernel debug info option other than "None" has been selected |
231 | in the "Debug information" choice below, indicating that debug | |
232 | information will be generated for build targets. | |
233 | ||
234 | choice | |
235 | prompt "Debug information" | |
236 | depends on DEBUG_KERNEL | |
237 | help | |
238 | Selecting something other than "None" results in a kernel image | |
239 | that will include debugging info resulting in a larger kernel image. | |
6dfc0665 DH |
240 | This adds debug symbols to the kernel and modules (gcc -g), and |
241 | is needed if you intend to use kernel crashdump or binary object | |
242 | tools like crash, kgdb, LKCD, gdb, etc on the kernel. | |
6dfc0665 | 243 | |
f9b3cd24 KC |
244 | Choose which version of DWARF debug info to emit. If unsure, |
245 | select "Toolchain default". | |
246 | ||
247 | config DEBUG_INFO_NONE | |
248 | bool "Disable debug information" | |
249 | help | |
250 | Do not build the kernel with debugging information, which will | |
251 | result in a faster and smaller build. | |
252 | ||
253 | config DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT | |
254 | bool "Rely on the toolchain's implicit default DWARF version" | |
255 | select DEBUG_INFO | |
256 | help | |
257 | The implicit default version of DWARF debug info produced by a | |
258 | toolchain changes over time. | |
259 | ||
260 | This can break consumers of the debug info that haven't upgraded to | |
261 | support newer revisions, and prevent testing newer versions, but | |
262 | those should be less common scenarios. | |
263 | ||
264 | config DEBUG_INFO_DWARF4 | |
265 | bool "Generate DWARF Version 4 debuginfo" | |
266 | select DEBUG_INFO | |
267 | help | |
268 | Generate DWARF v4 debug info. This requires gcc 4.5+ and gdb 7.0+. | |
269 | ||
270 | If you have consumers of DWARF debug info that are not ready for | |
271 | newer revisions of DWARF, you may wish to choose this or have your | |
272 | config select this. | |
273 | ||
274 | config DEBUG_INFO_DWARF5 | |
275 | bool "Generate DWARF Version 5 debuginfo" | |
276 | select DEBUG_INFO | |
277 | depends on !CC_IS_CLANG || (CC_IS_CLANG && (AS_IS_LLVM || (AS_IS_GNU && AS_VERSION >= 23502))) | |
278 | help | |
279 | Generate DWARF v5 debug info. Requires binutils 2.35.2, gcc 5.0+ (gcc | |
280 | 5.0+ accepts the -gdwarf-5 flag but only had partial support for some | |
281 | draft features until 7.0), and gdb 8.0+. | |
282 | ||
283 | Changes to the structure of debug info in Version 5 allow for around | |
284 | 15-18% savings in resulting image and debug info section sizes as | |
285 | compared to DWARF Version 4. DWARF Version 5 standardizes previous | |
286 | extensions such as accelerators for symbol indexing and the format | |
287 | for fission (.dwo/.dwp) files. Users may not want to select this | |
288 | config if they rely on tooling that has not yet been updated to | |
289 | support DWARF Version 5. | |
290 | ||
291 | endchoice # "Debug information" | |
6dfc0665 | 292 | |
695afd3d SD |
293 | if DEBUG_INFO |
294 | ||
6dfc0665 DH |
295 | config DEBUG_INFO_REDUCED |
296 | bool "Reduce debugging information" | |
6dfc0665 DH |
297 | help |
298 | If you say Y here gcc is instructed to generate less debugging | |
299 | information for structure types. This means that tools that | |
300 | need full debugging information (like kgdb or systemtap) won't | |
301 | be happy. But if you merely need debugging information to | |
302 | resolve line numbers there is no loss. Advantage is that | |
303 | build directory object sizes shrink dramatically over a full | |
304 | DEBUG_INFO build and compile times are reduced too. | |
305 | Only works with newer gcc versions. | |
306 | ||
10e68b02 ND |
307 | config DEBUG_INFO_COMPRESSED |
308 | bool "Compressed debugging information" | |
10e68b02 | 309 | depends on $(cc-option,-gz=zlib) |
10e68b02 ND |
310 | depends on $(ld-option,--compress-debug-sections=zlib) |
311 | help | |
312 | Compress the debug information using zlib. Requires GCC 5.0+ or Clang | |
313 | 5.0+, binutils 2.26+, and zlib. | |
314 | ||
315 | Users of dpkg-deb via scripts/package/builddeb may find an increase in | |
316 | size of their debug .deb packages with this config set, due to the | |
317 | debug info being compressed with zlib, then the object files being | |
318 | recompressed with a different compression scheme. But this is still | |
319 | preferable to setting $KDEB_COMPRESS to "none" which would be even | |
320 | larger. | |
321 | ||
866ced95 AK |
322 | config DEBUG_INFO_SPLIT |
323 | bool "Produce split debuginfo in .dwo files" | |
9d937444 | 324 | depends on $(cc-option,-gsplit-dwarf) |
866ced95 AK |
325 | help |
326 | Generate debug info into separate .dwo files. This significantly | |
327 | reduces the build directory size for builds with DEBUG_INFO, | |
328 | because it stores the information only once on disk in .dwo | |
329 | files instead of multiple times in object files and executables. | |
330 | In addition the debug information is also compressed. | |
331 | ||
332 | Requires recent gcc (4.7+) and recent gdb/binutils. | |
333 | Any tool that packages or reads debug information would need | |
334 | to know about the .dwo files and include them. | |
335 | Incompatible with older versions of ccache. | |
336 | ||
e83b9f55 AN |
337 | config DEBUG_INFO_BTF |
338 | bool "Generate BTF typeinfo" | |
7d32e693 SB |
339 | depends on !DEBUG_INFO_SPLIT && !DEBUG_INFO_REDUCED |
340 | depends on !GCC_PLUGIN_RANDSTRUCT || COMPILE_TEST | |
d9847eb8 | 341 | depends on BPF_SYSCALL |
52deda95 | 342 | depends on !DEBUG_INFO_DWARF5 || PAHOLE_VERSION >= 121 |
e83b9f55 AN |
343 | help |
344 | Generate deduplicated BTF type information from DWARF debug info. | |
345 | Turning this on expects presence of pahole tool, which will convert | |
346 | DWARF type info into equivalent deduplicated BTF type info. | |
347 | ||
5f9ae91f | 348 | config PAHOLE_HAS_SPLIT_BTF |
6323c813 | 349 | def_bool PAHOLE_VERSION >= 119 |
5f9ae91f | 350 | |
7472d5a6 | 351 | config PAHOLE_HAS_BTF_TAG |
6323c813 | 352 | def_bool PAHOLE_VERSION >= 123 |
7472d5a6 YS |
353 | depends on CC_IS_CLANG |
354 | help | |
355 | Decide whether pahole emits btf_tag attributes (btf_type_tag and | |
356 | btf_decl_tag) or not. Currently only clang compiler implements | |
357 | these attributes, so make the config depend on CC_IS_CLANG. | |
5f9ae91f AN |
358 | |
359 | config DEBUG_INFO_BTF_MODULES | |
360 | def_bool y | |
361 | depends on DEBUG_INFO_BTF && MODULES && PAHOLE_HAS_SPLIT_BTF | |
362 | help | |
363 | Generate compact split BTF type information for kernel modules. | |
364 | ||
5e214f2e CB |
365 | config MODULE_ALLOW_BTF_MISMATCH |
366 | bool "Allow loading modules with non-matching BTF type info" | |
367 | depends on DEBUG_INFO_BTF_MODULES | |
368 | help | |
369 | For modules whose split BTF does not match vmlinux, load without | |
370 | BTF rather than refusing to load. The default behavior with | |
371 | module BTF enabled is to reject modules with such mismatches; | |
372 | this option will still load module BTF where possible but ignore | |
373 | it when a mismatch is found. | |
374 | ||
3ee7b3fa JK |
375 | config GDB_SCRIPTS |
376 | bool "Provide GDB scripts for kernel debugging" | |
3ee7b3fa JK |
377 | help |
378 | This creates the required links to GDB helper scripts in the | |
379 | build directory. If you load vmlinux into gdb, the helper | |
380 | scripts will be automatically imported by gdb as well, and | |
381 | additional functions are available to analyze a Linux kernel | |
700199b0 AP |
382 | instance. See Documentation/dev-tools/gdb-kernel-debugging.rst |
383 | for further details. | |
3ee7b3fa | 384 | |
695afd3d SD |
385 | endif # DEBUG_INFO |
386 | ||
35bb5b1e | 387 | config FRAME_WARN |
a83e4ca2 | 388 | int "Warn for stack frames larger than" |
35bb5b1e | 389 | range 0 8192 |
0e07f663 | 390 | default 2048 if GCC_PLUGIN_LATENT_ENTROPY |
8d192bec HD |
391 | default 2048 if PARISC |
392 | default 1536 if (!64BIT && XTENSA) | |
393 | default 1024 if !64BIT | |
35bb5b1e AK |
394 | default 2048 if 64BIT |
395 | help | |
396 | Tell gcc to warn at build time for stack frames larger than this. | |
397 | Setting this too low will cause a lot of warnings. | |
398 | Setting it to 0 disables the warning. | |
35bb5b1e | 399 | |
99657c78 RD |
400 | config STRIP_ASM_SYMS |
401 | bool "Strip assembler-generated symbols during link" | |
402 | default n | |
403 | help | |
404 | Strip internal assembler-generated symbols during a link (symbols | |
405 | that look like '.Lxxx') so they don't pollute the output of | |
406 | get_wchan() and suchlike. | |
407 | ||
1873e870 | 408 | config READABLE_ASM |
68d4b3df KK |
409 | bool "Generate readable assembler code" |
410 | depends on DEBUG_KERNEL | |
7d73c3e9 | 411 | depends on CC_IS_GCC |
bf4735a4 | 412 | help |
68d4b3df KK |
413 | Disable some compiler optimizations that tend to generate human unreadable |
414 | assembler output. This may make the kernel slightly slower, but it helps | |
415 | to keep kernel developers who have to stare a lot at assembler listings | |
416 | sane. | |
bf4735a4 | 417 | |
e949f4c2 MY |
418 | config HEADERS_INSTALL |
419 | bool "Install uapi headers to usr/include" | |
bf4735a4 DM |
420 | depends on !UML |
421 | help | |
e949f4c2 MY |
422 | This option will install uapi headers (headers exported to user-space) |
423 | into the usr/include directory for use during the kernel build. | |
424 | This is unneeded for building the kernel itself, but needed for some | |
425 | user-space program samples. It is also needed by some features such | |
426 | as uapi header sanity checks. | |
427 | ||
91341d4b SR |
428 | config DEBUG_SECTION_MISMATCH |
429 | bool "Enable full Section mismatch analysis" | |
7d73c3e9 | 430 | depends on CC_IS_GCC |
91341d4b SR |
431 | help |
432 | The section mismatch analysis checks if there are illegal | |
433 | references from one section to another section. | |
e809ab01 MW |
434 | During linktime or runtime, some sections are dropped; |
435 | any use of code/data previously in these sections would | |
91341d4b | 436 | most likely result in an oops. |
e809ab01 | 437 | In the code, functions and variables are annotated with |
0db0628d | 438 | __init,, etc. (see the full list in include/linux/init.h), |
d6fbfa4f | 439 | which results in the code/data being placed in specific sections. |
e809ab01 MW |
440 | The section mismatch analysis is always performed after a full |
441 | kernel build, and enabling this option causes the following | |
b7dca6dd | 442 | additional step to occur: |
e809ab01 MW |
443 | - Add the option -fno-inline-functions-called-once to gcc commands. |
444 | When inlining a function annotated with __init in a non-init | |
445 | function, we would lose the section information and thus | |
91341d4b | 446 | the analysis would not catch the illegal reference. |
e809ab01 MW |
447 | This option tells gcc to inline less (but it does result in |
448 | a larger kernel). | |
91341d4b | 449 | |
47490ec1 NB |
450 | config SECTION_MISMATCH_WARN_ONLY |
451 | bool "Make section mismatch errors non-fatal" | |
452 | default y | |
453 | help | |
454 | If you say N here, the build process will fail if there are any | |
455 | section mismatch, instead of just throwing warnings. | |
456 | ||
457 | If unsure, say Y. | |
458 | ||
cf536e18 | 459 | config DEBUG_FORCE_FUNCTION_ALIGN_64B |
1bf18da6 FT |
460 | bool "Force all function address 64B aligned" |
461 | depends on EXPERT && (X86_64 || ARM64 || PPC32 || PPC64 || ARC) | |
09c60546 FT |
462 | help |
463 | There are cases that a commit from one domain changes the function | |
464 | address alignment of other domains, and cause magic performance | |
465 | bump (regression or improvement). Enable this option will help to | |
466 | verify if the bump is caused by function alignment changes, while | |
467 | it will slightly increase the kernel size and affect icache usage. | |
468 | ||
469 | It is mainly for debug and performance tuning use. | |
470 | ||
6dfc0665 DH |
471 | # |
472 | # Select this config option from the architecture Kconfig, if it | |
473 | # is preferred to always offer frame pointers as a config | |
474 | # option on the architecture (regardless of KERNEL_DEBUG): | |
475 | # | |
476 | config ARCH_WANT_FRAME_POINTERS | |
477 | bool | |
f346f4b3 | 478 | |
6dfc0665 DH |
479 | config FRAME_POINTER |
480 | bool "Compile the kernel with frame pointers" | |
a687a533 | 481 | depends on DEBUG_KERNEL && (M68K || UML || SUPERH) || ARCH_WANT_FRAME_POINTERS |
6dfc0665 | 482 | default y if (DEBUG_INFO && UML) || ARCH_WANT_FRAME_POINTERS |
a304e1b8 | 483 | help |
6dfc0665 DH |
484 | If you say Y here the resulting kernel image will be slightly |
485 | larger and slower, but it gives very useful debugging information | |
486 | in case of kernel bugs. (precise oopses/stacktraces/warnings) | |
a304e1b8 | 487 | |
03f16cd0 JP |
488 | config OBJTOOL |
489 | bool | |
490 | ||
b9ab5ebb JP |
491 | config STACK_VALIDATION |
492 | bool "Compile-time stack metadata validation" | |
03f16cd0 JP |
493 | depends on HAVE_STACK_VALIDATION && UNWINDER_FRAME_POINTER |
494 | select OBJTOOL | |
b9ab5ebb JP |
495 | default n |
496 | help | |
03f16cd0 JP |
497 | Validate frame pointer rules at compile-time. This helps ensure that |
498 | runtime stack traces are more reliable. | |
ee9f8fce | 499 | |
b9ab5ebb JP |
500 | For more information, see |
501 | tools/objtool/Documentation/stack-validation.txt. | |
502 | ||
0f620cef | 503 | config NOINSTR_VALIDATION |
6804c1af | 504 | bool |
03f16cd0 JP |
505 | depends on HAVE_OBJTOOL && DEBUG_ENTRY |
506 | select OBJTOOL | |
6804c1af PZ |
507 | default y |
508 | ||
5cc12472 RV |
509 | config VMLINUX_MAP |
510 | bool "Generate vmlinux.map file when linking" | |
511 | depends on EXPERT | |
512 | help | |
513 | Selecting this option will pass "-Map=vmlinux.map" to ld | |
514 | when linking vmlinux. That file can be useful for verifying | |
515 | and debugging magic section games, and for seeing which | |
516 | pieces of code get eliminated with | |
517 | CONFIG_LD_DEAD_CODE_DATA_ELIMINATION. | |
518 | ||
6dfc0665 DH |
519 | config DEBUG_FORCE_WEAK_PER_CPU |
520 | bool "Force weak per-cpu definitions" | |
521 | depends on DEBUG_KERNEL | |
8446f1d3 | 522 | help |
6dfc0665 DH |
523 | s390 and alpha require percpu variables in modules to be |
524 | defined weak to work around addressing range issue which | |
525 | puts the following two restrictions on percpu variable | |
526 | definitions. | |
8446f1d3 | 527 | |
6dfc0665 DH |
528 | 1. percpu symbols must be unique whether static or not |
529 | 2. percpu variables can't be defined inside a function | |
8446f1d3 | 530 | |
6dfc0665 DH |
531 | To ensure that generic code follows the above rules, this |
532 | option forces all percpu variables to be defined as weak. | |
5f329089 | 533 | |
6dfc0665 | 534 | endmenu # "Compiler options" |
8446f1d3 | 535 | |
6210b640 CD |
536 | menu "Generic Kernel Debugging Instruments" |
537 | ||
6dfc0665 DH |
538 | config MAGIC_SYSRQ |
539 | bool "Magic SysRq key" | |
540 | depends on !UML | |
541 | help | |
542 | If you say Y here, you will have some control over the system even | |
543 | if the system crashes for example during kernel debugging (e.g., you | |
544 | will be able to flush the buffer cache to disk, reboot the system | |
545 | immediately or dump some status information). This is accomplished | |
546 | by pressing various keys while holding SysRq (Alt+PrintScreen). It | |
547 | also works on a serial console (on PC hardware at least), if you | |
548 | send a BREAK and then within 5 seconds a command keypress. The | |
f8998c22 HH |
549 | keys are documented in <file:Documentation/admin-guide/sysrq.rst>. |
550 | Don't say Y unless you really know what this hack does. | |
8446f1d3 | 551 | |
8eaede49 BH |
552 | config MAGIC_SYSRQ_DEFAULT_ENABLE |
553 | hex "Enable magic SysRq key functions by default" | |
554 | depends on MAGIC_SYSRQ | |
555 | default 0x1 | |
556 | help | |
557 | Specifies which SysRq key functions are enabled by default. | |
558 | This may be set to 1 or 0 to enable or disable them all, or | |
f8998c22 | 559 | to a bitmask as described in Documentation/admin-guide/sysrq.rst. |
8eaede49 | 560 | |
732dbf3a FF |
561 | config MAGIC_SYSRQ_SERIAL |
562 | bool "Enable magic SysRq key over serial" | |
563 | depends on MAGIC_SYSRQ | |
564 | default y | |
565 | help | |
566 | Many embedded boards have a disconnected TTL level serial which can | |
567 | generate some garbage that can lead to spurious false sysrq detects. | |
568 | This option allows you to decide whether you want to enable the | |
569 | magic SysRq key. | |
570 | ||
68af4317 DS |
571 | config MAGIC_SYSRQ_SERIAL_SEQUENCE |
572 | string "Char sequence that enables magic SysRq over serial" | |
573 | depends on MAGIC_SYSRQ_SERIAL | |
574 | default "" | |
575 | help | |
576 | Specifies a sequence of characters that can follow BREAK to enable | |
577 | SysRq on a serial console. | |
578 | ||
d3394b3d DS |
579 | If unsure, leave an empty string and the option will not be enabled. |
580 | ||
ec29a5c1 CD |
581 | config DEBUG_FS |
582 | bool "Debug Filesystem" | |
583 | help | |
584 | debugfs is a virtual file system that kernel developers use to put | |
585 | debugging files into. Enable this option to be able to read and | |
586 | write to these files. | |
587 | ||
588 | For detailed documentation on the debugfs API, see | |
589 | Documentation/filesystems/. | |
590 | ||
591 | If unsure, say N. | |
592 | ||
a24c6f7b PE |
593 | choice |
594 | prompt "Debugfs default access" | |
595 | depends on DEBUG_FS | |
596 | default DEBUG_FS_ALLOW_ALL | |
597 | help | |
598 | This selects the default access restrictions for debugfs. | |
599 | It can be overridden with kernel command line option | |
600 | debugfs=[on,no-mount,off]. The restrictions apply for API access | |
601 | and filesystem registration. | |
602 | ||
603 | config DEBUG_FS_ALLOW_ALL | |
604 | bool "Access normal" | |
605 | help | |
606 | No restrictions apply. Both API and filesystem registration | |
607 | is on. This is the normal default operation. | |
608 | ||
609 | config DEBUG_FS_DISALLOW_MOUNT | |
610 | bool "Do not register debugfs as filesystem" | |
611 | help | |
612 | The API is open but filesystem is not loaded. Clients can still do | |
613 | their work and read with debug tools that do not need | |
614 | debugfs filesystem. | |
615 | ||
616 | config DEBUG_FS_ALLOW_NONE | |
617 | bool "No access" | |
618 | help | |
619 | Access is off. Clients get -PERM when trying to create nodes in | |
620 | debugfs tree and debugfs is not registered as a filesystem. | |
621 | Client can then back-off or continue without debugfs access. | |
622 | ||
623 | endchoice | |
624 | ||
6210b640 | 625 | source "lib/Kconfig.kgdb" |
6210b640 | 626 | source "lib/Kconfig.ubsan" |
2645d432 | 627 | source "lib/Kconfig.kcsan" |
6210b640 CD |
628 | |
629 | endmenu | |
630 | ||
4d92b95f ED |
631 | menu "Networking Debugging" |
632 | ||
633 | source "net/Kconfig.debug" | |
634 | ||
635 | endmenu # "Networking Debugging" | |
c66d7a27 | 636 | |
0610c8a8 | 637 | menu "Memory Debugging" |
fef2c9bc | 638 | |
8636a1f9 | 639 | source "mm/Kconfig.debug" |
fef2c9bc | 640 | |
0610c8a8 DH |
641 | config DEBUG_OBJECTS |
642 | bool "Debug object operations" | |
643 | depends on DEBUG_KERNEL | |
9c44bc03 | 644 | help |
0610c8a8 DH |
645 | If you say Y here, additional code will be inserted into the |
646 | kernel to track the life time of various objects and validate | |
647 | the operations on those objects. | |
9c44bc03 | 648 | |
0610c8a8 DH |
649 | config DEBUG_OBJECTS_SELFTEST |
650 | bool "Debug objects selftest" | |
651 | depends on DEBUG_OBJECTS | |
652 | help | |
653 | This enables the selftest of the object debug code. | |
9c44bc03 | 654 | |
0610c8a8 DH |
655 | config DEBUG_OBJECTS_FREE |
656 | bool "Debug objects in freed memory" | |
657 | depends on DEBUG_OBJECTS | |
658 | help | |
659 | This enables checks whether a k/v free operation frees an area | |
660 | which contains an object which has not been deactivated | |
661 | properly. This can make kmalloc/kfree-intensive workloads | |
662 | much slower. | |
3ac7fe5a | 663 | |
c6f3a97f TG |
664 | config DEBUG_OBJECTS_TIMERS |
665 | bool "Debug timer objects" | |
666 | depends on DEBUG_OBJECTS | |
667 | help | |
668 | If you say Y here, additional code will be inserted into the | |
669 | timer routines to track the life time of timer objects and | |
670 | validate the timer operations. | |
671 | ||
dc186ad7 TG |
672 | config DEBUG_OBJECTS_WORK |
673 | bool "Debug work objects" | |
674 | depends on DEBUG_OBJECTS | |
675 | help | |
676 | If you say Y here, additional code will be inserted into the | |
677 | work queue routines to track the life time of work objects and | |
678 | validate the work operations. | |
679 | ||
551d55a9 MD |
680 | config DEBUG_OBJECTS_RCU_HEAD |
681 | bool "Debug RCU callbacks objects" | |
fc2ecf7e | 682 | depends on DEBUG_OBJECTS |
551d55a9 MD |
683 | help |
684 | Enable this to turn on debugging of RCU list heads (call_rcu() usage). | |
685 | ||
e2852ae8 TH |
686 | config DEBUG_OBJECTS_PERCPU_COUNTER |
687 | bool "Debug percpu counter objects" | |
688 | depends on DEBUG_OBJECTS | |
689 | help | |
690 | If you say Y here, additional code will be inserted into the | |
691 | percpu counter routines to track the life time of percpu counter | |
692 | objects and validate the percpu counter operations. | |
693 | ||
3ae70205 IM |
694 | config DEBUG_OBJECTS_ENABLE_DEFAULT |
695 | int "debug_objects bootup default value (0-1)" | |
68d4b3df KK |
696 | range 0 1 |
697 | default "1" | |
698 | depends on DEBUG_OBJECTS | |
699 | help | |
700 | Debug objects boot parameter default value | |
3ae70205 | 701 | |
1da177e4 | 702 | config DEBUG_SLAB |
4a2f0acf | 703 | bool "Debug slab memory allocations" |
4675ff05 | 704 | depends on DEBUG_KERNEL && SLAB |
1da177e4 LT |
705 | help |
706 | Say Y here to have the kernel do limited verification on memory | |
707 | allocation as well as poisoning memory on free to catch use of freed | |
708 | memory. This can make kmalloc/kfree-intensive workloads much slower. | |
709 | ||
f0630fff CL |
710 | config SLUB_DEBUG_ON |
711 | bool "SLUB debugging on by default" | |
4675ff05 | 712 | depends on SLUB && SLUB_DEBUG |
f0630fff CL |
713 | default n |
714 | help | |
715 | Boot with debugging on by default. SLUB boots by default with | |
716 | the runtime debug capabilities switched off. Enabling this is | |
717 | equivalent to specifying the "slub_debug" parameter on boot. | |
718 | There is no support for more fine grained debug control like | |
719 | possible with slub_debug=xxx. SLUB debugging may be switched | |
720 | off in a kernel built with CONFIG_SLUB_DEBUG_ON by specifying | |
721 | "slub_debug=-". | |
722 | ||
8ff12cfc CL |
723 | config SLUB_STATS |
724 | default n | |
725 | bool "Enable SLUB performance statistics" | |
ab4d5ed5 | 726 | depends on SLUB && SYSFS |
8ff12cfc CL |
727 | help |
728 | SLUB statistics are useful to debug SLUBs allocation behavior in | |
729 | order find ways to optimize the allocator. This should never be | |
730 | enabled for production use since keeping statistics slows down | |
731 | the allocator by a few percentage points. The slabinfo command | |
732 | supports the determination of the most active slabs to figure | |
733 | out which slabs are relevant to a particular load. | |
734 | Try running: slabinfo -DA | |
735 | ||
b69ec42b CM |
736 | config HAVE_DEBUG_KMEMLEAK |
737 | bool | |
738 | ||
3bba00d7 CM |
739 | config DEBUG_KMEMLEAK |
740 | bool "Kernel memory leak detector" | |
525c1f92 | 741 | depends on DEBUG_KERNEL && HAVE_DEBUG_KMEMLEAK |
79e0d9bd | 742 | select DEBUG_FS |
3bba00d7 CM |
743 | select STACKTRACE if STACKTRACE_SUPPORT |
744 | select KALLSYMS | |
b60e26a2 | 745 | select CRC32 |
3bba00d7 CM |
746 | help |
747 | Say Y here if you want to enable the memory leak | |
748 | detector. The memory allocation/freeing is traced in a way | |
749 | similar to the Boehm's conservative garbage collector, the | |
750 | difference being that the orphan objects are not freed but | |
751 | only shown in /sys/kernel/debug/kmemleak. Enabling this | |
752 | feature will introduce an overhead to memory | |
700199b0 | 753 | allocations. See Documentation/dev-tools/kmemleak.rst for more |
3bba00d7 CM |
754 | details. |
755 | ||
0610c8a8 DH |
756 | Enabling DEBUG_SLAB or SLUB_DEBUG may increase the chances |
757 | of finding leaks due to the slab objects poisoning. | |
758 | ||
759 | In order to access the kmemleak file, debugfs needs to be | |
760 | mounted (usually at /sys/kernel/debug). | |
761 | ||
c5665868 CM |
762 | config DEBUG_KMEMLEAK_MEM_POOL_SIZE |
763 | int "Kmemleak memory pool size" | |
0610c8a8 | 764 | depends on DEBUG_KMEMLEAK |
c59180ae | 765 | range 200 1000000 |
b751c52b | 766 | default 16000 |
0610c8a8 DH |
767 | help |
768 | Kmemleak must track all the memory allocations to avoid | |
769 | reporting false positives. Since memory may be allocated or | |
c5665868 CM |
770 | freed before kmemleak is fully initialised, use a static pool |
771 | of metadata objects to track such callbacks. After kmemleak is | |
772 | fully initialised, this memory pool acts as an emergency one | |
773 | if slab allocations fail. | |
0610c8a8 DH |
774 | |
775 | config DEBUG_KMEMLEAK_TEST | |
776 | tristate "Simple test for the kernel memory leak detector" | |
777 | depends on DEBUG_KMEMLEAK && m | |
778 | help | |
779 | This option enables a module that explicitly leaks memory. | |
780 | ||
781 | If unsure, say N. | |
782 | ||
783 | config DEBUG_KMEMLEAK_DEFAULT_OFF | |
784 | bool "Default kmemleak to off" | |
785 | depends on DEBUG_KMEMLEAK | |
786 | help | |
787 | Say Y here to disable kmemleak by default. It can then be enabled | |
788 | on the command line via kmemleak=on. | |
789 | ||
d53ce042 SK |
790 | config DEBUG_KMEMLEAK_AUTO_SCAN |
791 | bool "Enable kmemleak auto scan thread on boot up" | |
792 | default y | |
793 | depends on DEBUG_KMEMLEAK | |
794 | help | |
795 | Depending on the cpu, kmemleak scan may be cpu intensive and can | |
796 | stall user tasks at times. This option enables/disables automatic | |
797 | kmemleak scan at boot up. | |
798 | ||
799 | Say N here to disable kmemleak auto scan thread to stop automatic | |
800 | scanning. Disabling this option disables automatic reporting of | |
801 | memory leaks. | |
802 | ||
803 | If unsure, say Y. | |
804 | ||
0610c8a8 DH |
805 | config DEBUG_STACK_USAGE |
806 | bool "Stack utilization instrumentation" | |
6c31da34 | 807 | depends on DEBUG_KERNEL && !IA64 |
0610c8a8 DH |
808 | help |
809 | Enables the display of the minimum amount of free stack which each | |
810 | task has ever had available in the sysrq-T and sysrq-P debug output. | |
811 | ||
812 | This option will slow down process creation somewhat. | |
813 | ||
dc9b9638 CD |
814 | config SCHED_STACK_END_CHECK |
815 | bool "Detect stack corruption on calls to schedule()" | |
816 | depends on DEBUG_KERNEL | |
817 | default n | |
818 | help | |
819 | This option checks for a stack overrun on calls to schedule(). | |
820 | If the stack end location is found to be over written always panic as | |
821 | the content of the corrupted region can no longer be trusted. | |
822 | This is to ensure no erroneous behaviour occurs which could result in | |
823 | data corruption or a sporadic crash at a later stage once the region | |
824 | is examined. The runtime overhead introduced is minimal. | |
825 | ||
399145f9 AK |
826 | config ARCH_HAS_DEBUG_VM_PGTABLE |
827 | bool | |
828 | help | |
829 | An architecture should select this when it can successfully | |
830 | build and run DEBUG_VM_PGTABLE. | |
831 | ||
0610c8a8 DH |
832 | config DEBUG_VM |
833 | bool "Debug VM" | |
834 | depends on DEBUG_KERNEL | |
835 | help | |
836 | Enable this to turn on extended checks in the virtual-memory system | |
68d4b3df | 837 | that may impact performance. |
0610c8a8 DH |
838 | |
839 | If unsure, say N. | |
840 | ||
4f115147 DB |
841 | config DEBUG_VM_VMACACHE |
842 | bool "Debug VMA caching" | |
843 | depends on DEBUG_VM | |
844 | help | |
845 | Enable this to turn on VMA caching debug information. Doing so | |
846 | can cause significant overhead, so only enable it in non-production | |
847 | environments. | |
848 | ||
849 | If unsure, say N. | |
850 | ||
0610c8a8 DH |
851 | config DEBUG_VM_RB |
852 | bool "Debug VM red-black trees" | |
853 | depends on DEBUG_VM | |
854 | help | |
a663dad6 | 855 | Enable VM red-black tree debugging information and extra validations. |
0610c8a8 DH |
856 | |
857 | If unsure, say N. | |
858 | ||
95ad9755 KS |
859 | config DEBUG_VM_PGFLAGS |
860 | bool "Debug page-flags operations" | |
861 | depends on DEBUG_VM | |
862 | help | |
863 | Enables extra validation on page flags operations. | |
864 | ||
865 | If unsure, say N. | |
866 | ||
399145f9 AK |
867 | config DEBUG_VM_PGTABLE |
868 | bool "Debug arch page table for semantics compliance" | |
869 | depends on MMU | |
870 | depends on ARCH_HAS_DEBUG_VM_PGTABLE | |
871 | default y if DEBUG_VM | |
872 | help | |
873 | This option provides a debug method which can be used to test | |
874 | architecture page table helper functions on various platforms in | |
875 | verifying if they comply with expected generic MM semantics. This | |
876 | will help architecture code in making sure that any changes or | |
877 | new additions of these helpers still conform to expected | |
878 | semantics of the generic MM. Platforms will have to opt in for | |
879 | this through ARCH_HAS_DEBUG_VM_PGTABLE. | |
880 | ||
881 | If unsure, say N. | |
882 | ||
fa5b6ec9 LA |
883 | config ARCH_HAS_DEBUG_VIRTUAL |
884 | bool | |
885 | ||
0610c8a8 DH |
886 | config DEBUG_VIRTUAL |
887 | bool "Debug VM translations" | |
fa5b6ec9 | 888 | depends on DEBUG_KERNEL && ARCH_HAS_DEBUG_VIRTUAL |
0610c8a8 DH |
889 | help |
890 | Enable some costly sanity checks in virtual to page code. This can | |
891 | catch mistakes with virt_to_page() and friends. | |
892 | ||
893 | If unsure, say N. | |
894 | ||
895 | config DEBUG_NOMMU_REGIONS | |
896 | bool "Debug the global anon/private NOMMU mapping region tree" | |
897 | depends on DEBUG_KERNEL && !MMU | |
898 | help | |
899 | This option causes the global tree of anonymous and private mapping | |
900 | regions to be regularly checked for invalid topology. | |
901 | ||
902 | config DEBUG_MEMORY_INIT | |
903 | bool "Debug memory initialisation" if EXPERT | |
904 | default !EXPERT | |
905 | help | |
906 | Enable this for additional checks during memory initialisation. | |
907 | The sanity checks verify aspects of the VM such as the memory model | |
908 | and other information provided by the architecture. Verbose | |
909 | information will be printed at KERN_DEBUG loglevel depending | |
910 | on the mminit_loglevel= command-line option. | |
911 | ||
912 | If unsure, say Y | |
913 | ||
914 | config MEMORY_NOTIFIER_ERROR_INJECT | |
915 | tristate "Memory hotplug notifier error injection module" | |
50f9481e | 916 | depends on MEMORY_HOTPLUG && NOTIFIER_ERROR_INJECTION |
0610c8a8 DH |
917 | help |
918 | This option provides the ability to inject artificial errors to | |
919 | memory hotplug notifier chain callbacks. It is controlled through | |
920 | debugfs interface under /sys/kernel/debug/notifier-error-inject/memory | |
921 | ||
922 | If the notifier call chain should be failed with some events | |
923 | notified, write the error code to "actions/<notifier event>/error". | |
924 | ||
925 | Example: Inject memory hotplug offline error (-12 == -ENOMEM) | |
926 | ||
927 | # cd /sys/kernel/debug/notifier-error-inject/memory | |
928 | # echo -12 > actions/MEM_GOING_OFFLINE/error | |
929 | # echo offline > /sys/devices/system/memory/memoryXXX/state | |
930 | bash: echo: write error: Cannot allocate memory | |
931 | ||
932 | To compile this code as a module, choose M here: the module will | |
933 | be called memory-notifier-error-inject. | |
934 | ||
935 | If unsure, say N. | |
936 | ||
937 | config DEBUG_PER_CPU_MAPS | |
938 | bool "Debug access to per_cpu maps" | |
939 | depends on DEBUG_KERNEL | |
940 | depends on SMP | |
941 | help | |
942 | Say Y to verify that the per_cpu map being accessed has | |
943 | been set up. This adds a fair amount of code to kernel memory | |
944 | and decreases performance. | |
945 | ||
946 | Say N if unsure. | |
947 | ||
6e799cb6 TG |
948 | config DEBUG_KMAP_LOCAL |
949 | bool "Debug kmap_local temporary mappings" | |
950 | depends on DEBUG_KERNEL && KMAP_LOCAL | |
951 | help | |
952 | This option enables additional error checking for the kmap_local | |
953 | infrastructure. Disable for production use. | |
954 | ||
0e91a0c6 TG |
955 | config ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP |
956 | bool | |
957 | ||
958 | config DEBUG_KMAP_LOCAL_FORCE_MAP | |
959 | bool "Enforce kmap_local temporary mappings" | |
960 | depends on DEBUG_KERNEL && ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP | |
961 | select KMAP_LOCAL | |
962 | select DEBUG_KMAP_LOCAL | |
963 | help | |
964 | This option enforces temporary mappings through the kmap_local | |
965 | mechanism for non-highmem pages and on non-highmem systems. | |
966 | Disable this for production systems! | |
967 | ||
0610c8a8 DH |
968 | config DEBUG_HIGHMEM |
969 | bool "Highmem debugging" | |
970 | depends on DEBUG_KERNEL && HIGHMEM | |
0e91a0c6 | 971 | select DEBUG_KMAP_LOCAL_FORCE_MAP if ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP |
6e799cb6 | 972 | select DEBUG_KMAP_LOCAL |
0610c8a8 | 973 | help |
b1357c9f GU |
974 | This option enables additional error checking for high memory |
975 | systems. Disable for production systems. | |
0610c8a8 DH |
976 | |
977 | config HAVE_DEBUG_STACKOVERFLOW | |
978 | bool | |
979 | ||
980 | config DEBUG_STACKOVERFLOW | |
981 | bool "Check for stack overflows" | |
982 | depends on DEBUG_KERNEL && HAVE_DEBUG_STACKOVERFLOW | |
a7f7f624 | 983 | help |
0610c8a8 | 984 | Say Y here if you want to check for overflows of kernel, IRQ |
edb0ec07 | 985 | and exception stacks (if your architecture uses them). This |
0610c8a8 DH |
986 | option will show detailed messages if free stack space drops |
987 | below a certain limit. | |
988 | ||
989 | These kinds of bugs usually occur when call-chains in the | |
990 | kernel get too deep, especially when interrupts are | |
991 | involved. | |
992 | ||
993 | Use this in cases where you see apparently random memory | |
994 | corruption, especially if it appears in 'struct thread_info' | |
995 | ||
996 | If in doubt, say "N". | |
997 | ||
0b24becc | 998 | source "lib/Kconfig.kasan" |
0ce20dd8 | 999 | source "lib/Kconfig.kfence" |
0b24becc | 1000 | |
0610c8a8 DH |
1001 | endmenu # "Memory Debugging" |
1002 | ||
a304e1b8 DW |
1003 | config DEBUG_SHIRQ |
1004 | bool "Debug shared IRQ handlers" | |
0244ad00 | 1005 | depends on DEBUG_KERNEL |
a304e1b8 | 1006 | help |
0a2fae2a WS |
1007 | Enable this to generate a spurious interrupt just before a shared |
1008 | interrupt handler is deregistered (generating one when registering | |
1009 | is currently disabled). Drivers need to handle this correctly. Some | |
1010 | don't and need to be caught. | |
a304e1b8 | 1011 | |
f43a289d CD |
1012 | menu "Debug Oops, Lockups and Hangs" |
1013 | ||
1014 | config PANIC_ON_OOPS | |
1015 | bool "Panic on Oops" | |
1016 | help | |
1017 | Say Y here to enable the kernel to panic when it oopses. This | |
1018 | has the same effect as setting oops=panic on the kernel command | |
1019 | line. | |
1020 | ||
1021 | This feature is useful to ensure that the kernel does not do | |
1022 | anything erroneous after an oops which could result in data | |
1023 | corruption or other issues. | |
1024 | ||
1025 | Say N if unsure. | |
1026 | ||
1027 | config PANIC_ON_OOPS_VALUE | |
1028 | int | |
1029 | range 0 1 | |
1030 | default 0 if !PANIC_ON_OOPS | |
1031 | default 1 if PANIC_ON_OOPS | |
1032 | ||
1033 | config PANIC_TIMEOUT | |
1034 | int "panic timeout" | |
1035 | default 0 | |
1036 | help | |
9d5b134f | 1037 | Set the timeout value (in seconds) until a reboot occurs when |
f43a289d CD |
1038 | the kernel panics. If n = 0, then we wait forever. A timeout |
1039 | value n > 0 will wait n seconds before rebooting, while a timeout | |
1040 | value n < 0 will reboot immediately. | |
92aef8fb | 1041 | |
58687acb | 1042 | config LOCKUP_DETECTOR |
05a4a952 NP |
1043 | bool |
1044 | ||
1045 | config SOFTLOCKUP_DETECTOR | |
1046 | bool "Detect Soft Lockups" | |
dea20a3f | 1047 | depends on DEBUG_KERNEL && !S390 |
05a4a952 | 1048 | select LOCKUP_DETECTOR |
8446f1d3 | 1049 | help |
58687acb | 1050 | Say Y here to enable the kernel to act as a watchdog to detect |
05a4a952 | 1051 | soft lockups. |
58687acb DZ |
1052 | |
1053 | Softlockups are bugs that cause the kernel to loop in kernel | |
5f329089 | 1054 | mode for more than 20 seconds, without giving other tasks a |
58687acb DZ |
1055 | chance to run. The current stack trace is displayed upon |
1056 | detection and the system will stay locked up. | |
8446f1d3 | 1057 | |
5f00ae0d RD |
1058 | config BOOTPARAM_SOFTLOCKUP_PANIC |
1059 | bool "Panic (Reboot) On Soft Lockups" | |
1060 | depends on SOFTLOCKUP_DETECTOR | |
1061 | help | |
1062 | Say Y here to enable the kernel to panic on "soft lockups", | |
1063 | which are bugs that cause the kernel to loop in kernel | |
1064 | mode for more than 20 seconds (configurable using the watchdog_thresh | |
1065 | sysctl), without giving other tasks a chance to run. | |
1066 | ||
1067 | The panic can be used in combination with panic_timeout, | |
1068 | to cause the system to reboot automatically after a | |
1069 | lockup has been detected. This feature is useful for | |
1070 | high-availability systems that have uptime guarantees and | |
1071 | where a lockup must be resolved ASAP. | |
1072 | ||
1073 | Say N if unsure. | |
1074 | ||
1075 | config BOOTPARAM_SOFTLOCKUP_PANIC_VALUE | |
1076 | int | |
1077 | depends on SOFTLOCKUP_DETECTOR | |
1078 | range 0 1 | |
1079 | default 0 if !BOOTPARAM_SOFTLOCKUP_PANIC | |
1080 | default 1 if BOOTPARAM_SOFTLOCKUP_PANIC | |
1081 | ||
05a4a952 NP |
1082 | config HARDLOCKUP_DETECTOR_PERF |
1083 | bool | |
1084 | select SOFTLOCKUP_DETECTOR | |
1085 | ||
7edaeb68 TG |
1086 | # |
1087 | # Enables a timestamp based low pass filter to compensate for perf based | |
1088 | # hard lockup detection which runs too fast due to turbo modes. | |
1089 | # | |
1090 | config HARDLOCKUP_CHECK_TIMESTAMP | |
1091 | bool | |
1092 | ||
05a4a952 NP |
1093 | # |
1094 | # arch/ can define HAVE_HARDLOCKUP_DETECTOR_ARCH to provide their own hard | |
1095 | # lockup detector rather than the perf based detector. | |
1096 | # | |
1097 | config HARDLOCKUP_DETECTOR | |
1098 | bool "Detect Hard Lockups" | |
1099 | depends on DEBUG_KERNEL && !S390 | |
1100 | depends on HAVE_HARDLOCKUP_DETECTOR_PERF || HAVE_HARDLOCKUP_DETECTOR_ARCH | |
1101 | select LOCKUP_DETECTOR | |
1102 | select HARDLOCKUP_DETECTOR_PERF if HAVE_HARDLOCKUP_DETECTOR_PERF | |
05a4a952 NP |
1103 | help |
1104 | Say Y here to enable the kernel to act as a watchdog to detect | |
1105 | hard lockups. | |
1106 | ||
58687acb | 1107 | Hardlockups are bugs that cause the CPU to loop in kernel mode |
5f329089 | 1108 | for more than 10 seconds, without letting other interrupts have a |
58687acb DZ |
1109 | chance to run. The current stack trace is displayed upon detection |
1110 | and the system will stay locked up. | |
8446f1d3 | 1111 | |
fef2c9bc DZ |
1112 | config BOOTPARAM_HARDLOCKUP_PANIC |
1113 | bool "Panic (Reboot) On Hard Lockups" | |
8f1f66ed | 1114 | depends on HARDLOCKUP_DETECTOR |
fef2c9bc DZ |
1115 | help |
1116 | Say Y here to enable the kernel to panic on "hard lockups", | |
1117 | which are bugs that cause the kernel to loop in kernel | |
5f329089 FLVC |
1118 | mode with interrupts disabled for more than 10 seconds (configurable |
1119 | using the watchdog_thresh sysctl). | |
fef2c9bc DZ |
1120 | |
1121 | Say N if unsure. | |
1122 | ||
1123 | config BOOTPARAM_HARDLOCKUP_PANIC_VALUE | |
1124 | int | |
8f1f66ed | 1125 | depends on HARDLOCKUP_DETECTOR |
fef2c9bc DZ |
1126 | range 0 1 |
1127 | default 0 if !BOOTPARAM_HARDLOCKUP_PANIC | |
1128 | default 1 if BOOTPARAM_HARDLOCKUP_PANIC | |
1129 | ||
e162b39a MSB |
1130 | config DETECT_HUNG_TASK |
1131 | bool "Detect Hung Tasks" | |
1132 | depends on DEBUG_KERNEL | |
05a4a952 | 1133 | default SOFTLOCKUP_DETECTOR |
e162b39a | 1134 | help |
0610c8a8 DH |
1135 | Say Y here to enable the kernel to detect "hung tasks", |
1136 | which are bugs that cause the task to be stuck in | |
96b03ab8 | 1137 | uninterruptible "D" state indefinitely. |
1da177e4 | 1138 | |
0610c8a8 DH |
1139 | When a hung task is detected, the kernel will print the |
1140 | current stack trace (which you should report), but the | |
1141 | task will stay in uninterruptible state. If lockdep is | |
1142 | enabled then all held locks will also be reported. This | |
1143 | feature has negligible overhead. | |
871751e2 | 1144 | |
0610c8a8 DH |
1145 | config DEFAULT_HUNG_TASK_TIMEOUT |
1146 | int "Default timeout for hung task detection (in seconds)" | |
1147 | depends on DETECT_HUNG_TASK | |
1148 | default 120 | |
f0630fff | 1149 | help |
0610c8a8 DH |
1150 | This option controls the default timeout (in seconds) used |
1151 | to determine when a task has become non-responsive and should | |
1152 | be considered hung. | |
f0630fff | 1153 | |
0610c8a8 DH |
1154 | It can be adjusted at runtime via the kernel.hung_task_timeout_secs |
1155 | sysctl or by writing a value to | |
1156 | /proc/sys/kernel/hung_task_timeout_secs. | |
8ff12cfc | 1157 | |
0610c8a8 DH |
1158 | A timeout of 0 disables the check. The default is two minutes. |
1159 | Keeping the default should be fine in most cases. | |
b69ec42b | 1160 | |
0610c8a8 DH |
1161 | config BOOTPARAM_HUNG_TASK_PANIC |
1162 | bool "Panic (Reboot) On Hung Tasks" | |
1163 | depends on DETECT_HUNG_TASK | |
3bba00d7 | 1164 | help |
0610c8a8 DH |
1165 | Say Y here to enable the kernel to panic on "hung tasks", |
1166 | which are bugs that cause the kernel to leave a task stuck | |
1167 | in uninterruptible "D" state. | |
3bba00d7 | 1168 | |
0610c8a8 DH |
1169 | The panic can be used in combination with panic_timeout, |
1170 | to cause the system to reboot automatically after a | |
1171 | hung task has been detected. This feature is useful for | |
1172 | high-availability systems that have uptime guarantees and | |
1173 | where a hung tasks must be resolved ASAP. | |
bf96d1e3 | 1174 | |
0610c8a8 | 1175 | Say N if unsure. |
bf96d1e3 | 1176 | |
0610c8a8 DH |
1177 | config BOOTPARAM_HUNG_TASK_PANIC_VALUE |
1178 | int | |
1179 | depends on DETECT_HUNG_TASK | |
1180 | range 0 1 | |
1181 | default 0 if !BOOTPARAM_HUNG_TASK_PANIC | |
1182 | default 1 if BOOTPARAM_HUNG_TASK_PANIC | |
3bba00d7 | 1183 | |
82607adc TH |
1184 | config WQ_WATCHDOG |
1185 | bool "Detect Workqueue Stalls" | |
1186 | depends on DEBUG_KERNEL | |
1187 | help | |
1188 | Say Y here to enable stall detection on workqueues. If a | |
1189 | worker pool doesn't make forward progress on a pending work | |
1190 | item for over a given amount of time, 30s by default, a | |
1191 | warning message is printed along with dump of workqueue | |
1192 | state. This can be configured through kernel parameter | |
1193 | "workqueue.watchdog_thresh" and its sysfs counterpart. | |
1194 | ||
30428ef5 KK |
1195 | config TEST_LOCKUP |
1196 | tristate "Test module to generate lockups" | |
63646bc9 | 1197 | depends on m |
30428ef5 KK |
1198 | help |
1199 | This builds the "test_lockup" module that helps to make sure | |
1200 | that watchdogs and lockup detectors are working properly. | |
1201 | ||
1202 | Depending on module parameters it could emulate soft or hard | |
1203 | lockup, "hung task", or locking arbitrary lock for a long time. | |
1204 | Also it could generate series of lockups with cooling-down periods. | |
1205 | ||
1206 | If unsure, say N. | |
1207 | ||
92aef8fb DH |
1208 | endmenu # "Debug lockups and hangs" |
1209 | ||
ebebdd09 | 1210 | menu "Scheduler Debugging" |
5800dc3c | 1211 | |
0610c8a8 DH |
1212 | config SCHED_DEBUG |
1213 | bool "Collect scheduler debugging info" | |
1214 | depends on DEBUG_KERNEL && PROC_FS | |
1215 | default y | |
0822ee4a | 1216 | help |
0610c8a8 DH |
1217 | If you say Y here, the /proc/sched_debug file will be provided |
1218 | that can help debug the scheduler. The runtime overhead of this | |
1219 | option is minimal. | |
0822ee4a | 1220 | |
f6db8347 NR |
1221 | config SCHED_INFO |
1222 | bool | |
1223 | default n | |
1224 | ||
0610c8a8 DH |
1225 | config SCHEDSTATS |
1226 | bool "Collect scheduler statistics" | |
1227 | depends on DEBUG_KERNEL && PROC_FS | |
f6db8347 | 1228 | select SCHED_INFO |
0610c8a8 DH |
1229 | help |
1230 | If you say Y here, additional code will be inserted into the | |
1231 | scheduler and related routines to collect statistics about | |
1232 | scheduler behavior and provide them in /proc/schedstat. These | |
1233 | stats may be useful for both tuning and debugging the scheduler | |
1234 | If you aren't debugging the scheduler or trying to tune a specific | |
1235 | application, you can say N to avoid the very slight overhead | |
1236 | this adds. | |
0822ee4a | 1237 | |
ebebdd09 | 1238 | endmenu |
0d9e2632 | 1239 | |
3c17ad19 JS |
1240 | config DEBUG_TIMEKEEPING |
1241 | bool "Enable extra timekeeping sanity checking" | |
1242 | help | |
1243 | This option will enable additional timekeeping sanity checks | |
1244 | which may be helpful when diagnosing issues where timekeeping | |
1245 | problems are suspected. | |
1246 | ||
1247 | This may include checks in the timekeeping hotpaths, so this | |
1248 | option may have a (very small) performance impact to some | |
1249 | workloads. | |
1250 | ||
1251 | If unsure, say N. | |
1252 | ||
1da177e4 LT |
1253 | config DEBUG_PREEMPT |
1254 | bool "Debug preemptible kernel" | |
9f472869 | 1255 | depends on DEBUG_KERNEL && PREEMPTION && TRACE_IRQFLAGS_SUPPORT |
1da177e4 LT |
1256 | default y |
1257 | help | |
1258 | If you say Y here then the kernel will use a debug variant of the | |
1259 | commonly used smp_processor_id() function and will print warnings | |
1260 | if kernel code uses it in a preemption-unsafe way. Also, the kernel | |
1261 | will detect preemption count underflows. | |
1262 | ||
9eade16b DH |
1263 | menu "Lock Debugging (spinlocks, mutexes, etc...)" |
1264 | ||
f07cbebb WL |
1265 | config LOCK_DEBUGGING_SUPPORT |
1266 | bool | |
1267 | depends on TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT | |
1268 | default y | |
1269 | ||
19193bca WL |
1270 | config PROVE_LOCKING |
1271 | bool "Lock debugging: prove locking correctness" | |
1272 | depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT | |
1273 | select LOCKDEP | |
1274 | select DEBUG_SPINLOCK | |
bb630f9f | 1275 | select DEBUG_MUTEXES if !PREEMPT_RT |
19193bca | 1276 | select DEBUG_RT_MUTEXES if RT_MUTEXES |
c71fd893 | 1277 | select DEBUG_RWSEMS |
19193bca WL |
1278 | select DEBUG_WW_MUTEX_SLOWPATH |
1279 | select DEBUG_LOCK_ALLOC | |
8fd8ad5c | 1280 | select PREEMPT_COUNT if !ARCH_NO_PREEMPT |
19193bca WL |
1281 | select TRACE_IRQFLAGS |
1282 | default n | |
1283 | help | |
1284 | This feature enables the kernel to prove that all locking | |
1285 | that occurs in the kernel runtime is mathematically | |
1286 | correct: that under no circumstance could an arbitrary (and | |
1287 | not yet triggered) combination of observed locking | |
1288 | sequences (on an arbitrary number of CPUs, running an | |
1289 | arbitrary number of tasks and interrupt contexts) cause a | |
1290 | deadlock. | |
1291 | ||
1292 | In short, this feature enables the kernel to report locking | |
1293 | related deadlocks before they actually occur. | |
1294 | ||
1295 | The proof does not depend on how hard and complex a | |
1296 | deadlock scenario would be to trigger: how many | |
1297 | participant CPUs, tasks and irq-contexts would be needed | |
1298 | for it to trigger. The proof also does not depend on | |
1299 | timing: if a race and a resulting deadlock is possible | |
1300 | theoretically (no matter how unlikely the race scenario | |
1301 | is), it will be proven so and will immediately be | |
1302 | reported by the kernel (once the event is observed that | |
1303 | makes the deadlock theoretically possible). | |
1304 | ||
1305 | If a deadlock is impossible (i.e. the locking rules, as | |
1306 | observed by the kernel, are mathematically correct), the | |
1307 | kernel reports nothing. | |
1308 | ||
1309 | NOTE: this feature can also be enabled for rwlocks, mutexes | |
1310 | and rwsems - in which case all dependencies between these | |
1311 | different locking variants are observed and mapped too, and | |
1312 | the proof of observed correctness is also maintained for an | |
1313 | arbitrary combination of these separate locking variants. | |
1314 | ||
387b1468 | 1315 | For more details, see Documentation/locking/lockdep-design.rst. |
19193bca | 1316 | |
de8f5e4f PZ |
1317 | config PROVE_RAW_LOCK_NESTING |
1318 | bool "Enable raw_spinlock - spinlock nesting checks" | |
1319 | depends on PROVE_LOCKING | |
1320 | default n | |
1321 | help | |
1322 | Enable the raw_spinlock vs. spinlock nesting checks which ensure | |
1323 | that the lock nesting rules for PREEMPT_RT enabled kernels are | |
1324 | not violated. | |
1325 | ||
1326 | NOTE: There are known nesting problems. So if you enable this | |
1327 | option expect lockdep splats until these problems have been fully | |
1328 | addressed which is work in progress. This config switch allows to | |
1329 | identify and analyze these problems. It will be removed and the | |
9dbbc3b9 | 1330 | check permanently enabled once the main issues have been fixed. |
de8f5e4f PZ |
1331 | |
1332 | If unsure, select N. | |
1333 | ||
19193bca WL |
1334 | config LOCK_STAT |
1335 | bool "Lock usage statistics" | |
1336 | depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT | |
1337 | select LOCKDEP | |
1338 | select DEBUG_SPINLOCK | |
bb630f9f | 1339 | select DEBUG_MUTEXES if !PREEMPT_RT |
19193bca WL |
1340 | select DEBUG_RT_MUTEXES if RT_MUTEXES |
1341 | select DEBUG_LOCK_ALLOC | |
1342 | default n | |
1343 | help | |
1344 | This feature enables tracking lock contention points | |
1345 | ||
387b1468 | 1346 | For more details, see Documentation/locking/lockstat.rst |
19193bca WL |
1347 | |
1348 | This also enables lock events required by "perf lock", | |
1349 | subcommand of perf. | |
1350 | If you want to use "perf lock", you also need to turn on | |
1351 | CONFIG_EVENT_TRACING. | |
1352 | ||
1353 | CONFIG_LOCK_STAT defines "contended" and "acquired" lock events. | |
1354 | (CONFIG_LOCKDEP defines "acquire" and "release" events.) | |
1355 | ||
e7eebaf6 IM |
1356 | config DEBUG_RT_MUTEXES |
1357 | bool "RT Mutex debugging, deadlock detection" | |
e7eebaf6 IM |
1358 | depends on DEBUG_KERNEL && RT_MUTEXES |
1359 | help | |
1360 | This allows rt mutex semantics violations and rt mutex related | |
1361 | deadlocks (lockups) to be detected and reported automatically. | |
1362 | ||
1da177e4 | 1363 | config DEBUG_SPINLOCK |
4d9f34ad | 1364 | bool "Spinlock and rw-lock debugging: basic checks" |
1da177e4 | 1365 | depends on DEBUG_KERNEL |
e335e3eb | 1366 | select UNINLINE_SPIN_UNLOCK |
1da177e4 LT |
1367 | help |
1368 | Say Y here and build SMP to catch missing spinlock initialization | |
1369 | and certain other kinds of spinlock errors commonly made. This is | |
1370 | best used in conjunction with the NMI watchdog so that spinlock | |
1371 | deadlocks are also debuggable. | |
1372 | ||
4d9f34ad IM |
1373 | config DEBUG_MUTEXES |
1374 | bool "Mutex debugging: basic checks" | |
bb630f9f | 1375 | depends on DEBUG_KERNEL && !PREEMPT_RT |
4d9f34ad IM |
1376 | help |
1377 | This feature allows mutex semantics violations to be detected and | |
1378 | reported. | |
1379 | ||
23010027 DV |
1380 | config DEBUG_WW_MUTEX_SLOWPATH |
1381 | bool "Wait/wound mutex debugging: Slowpath testing" | |
f07cbebb | 1382 | depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT |
23010027 DV |
1383 | select DEBUG_LOCK_ALLOC |
1384 | select DEBUG_SPINLOCK | |
bb630f9f TG |
1385 | select DEBUG_MUTEXES if !PREEMPT_RT |
1386 | select DEBUG_RT_MUTEXES if PREEMPT_RT | |
23010027 DV |
1387 | help |
1388 | This feature enables slowpath testing for w/w mutex users by | |
1389 | injecting additional -EDEADLK wound/backoff cases. Together with | |
1390 | the full mutex checks enabled with (CONFIG_PROVE_LOCKING) this | |
1391 | will test all possible w/w mutex interface abuse with the | |
1392 | exception of simply not acquiring all the required locks. | |
4d692373 RC |
1393 | Note that this feature can introduce significant overhead, so |
1394 | it really should not be enabled in a production or distro kernel, | |
1395 | even a debug kernel. If you are a driver writer, enable it. If | |
1396 | you are a distro, do not. | |
23010027 | 1397 | |
5149cbac WL |
1398 | config DEBUG_RWSEMS |
1399 | bool "RW Semaphore debugging: basic checks" | |
c71fd893 | 1400 | depends on DEBUG_KERNEL |
5149cbac | 1401 | help |
c71fd893 WL |
1402 | This debugging feature allows mismatched rw semaphore locks |
1403 | and unlocks to be detected and reported. | |
5149cbac | 1404 | |
4d9f34ad IM |
1405 | config DEBUG_LOCK_ALLOC |
1406 | bool "Lock debugging: detect incorrect freeing of live locks" | |
f07cbebb | 1407 | depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT |
4d9f34ad | 1408 | select DEBUG_SPINLOCK |
bb630f9f | 1409 | select DEBUG_MUTEXES if !PREEMPT_RT |
f5694788 | 1410 | select DEBUG_RT_MUTEXES if RT_MUTEXES |
4d9f34ad IM |
1411 | select LOCKDEP |
1412 | help | |
1413 | This feature will check whether any held lock (spinlock, rwlock, | |
1414 | mutex or rwsem) is incorrectly freed by the kernel, via any of the | |
1415 | memory-freeing routines (kfree(), kmem_cache_free(), free_pages(), | |
1416 | vfree(), etc.), whether a live lock is incorrectly reinitialized via | |
1417 | spin_lock_init()/mutex_init()/etc., or whether there is any lock | |
1418 | held during task exit. | |
1419 | ||
4d9f34ad IM |
1420 | config LOCKDEP |
1421 | bool | |
f07cbebb | 1422 | depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT |
4d9f34ad | 1423 | select STACKTRACE |
4d9f34ad IM |
1424 | select KALLSYMS |
1425 | select KALLSYMS_ALL | |
1426 | ||
395102db DJ |
1427 | config LOCKDEP_SMALL |
1428 | bool | |
1429 | ||
5dc33592 TH |
1430 | config LOCKDEP_BITS |
1431 | int "Bitsize for MAX_LOCKDEP_ENTRIES" | |
1432 | depends on LOCKDEP && !LOCKDEP_SMALL | |
1433 | range 10 30 | |
1434 | default 15 | |
1435 | help | |
1436 | Try increasing this value if you hit "BUG: MAX_LOCKDEP_ENTRIES too low!" message. | |
1437 | ||
1438 | config LOCKDEP_CHAINS_BITS | |
1439 | int "Bitsize for MAX_LOCKDEP_CHAINS" | |
1440 | depends on LOCKDEP && !LOCKDEP_SMALL | |
1441 | range 10 30 | |
1442 | default 16 | |
1443 | help | |
1444 | Try increasing this value if you hit "BUG: MAX_LOCKDEP_CHAINS too low!" message. | |
1445 | ||
1446 | config LOCKDEP_STACK_TRACE_BITS | |
1447 | int "Bitsize for MAX_STACK_TRACE_ENTRIES" | |
1448 | depends on LOCKDEP && !LOCKDEP_SMALL | |
1449 | range 10 30 | |
1450 | default 19 | |
1451 | help | |
1452 | Try increasing this value if you hit "BUG: MAX_STACK_TRACE_ENTRIES too low!" message. | |
1453 | ||
1454 | config LOCKDEP_STACK_TRACE_HASH_BITS | |
1455 | int "Bitsize for STACK_TRACE_HASH_SIZE" | |
1456 | depends on LOCKDEP && !LOCKDEP_SMALL | |
1457 | range 10 30 | |
1458 | default 14 | |
1459 | help | |
1460 | Try increasing this value if you need large MAX_STACK_TRACE_ENTRIES. | |
1461 | ||
1462 | config LOCKDEP_CIRCULAR_QUEUE_BITS | |
1463 | int "Bitsize for elements in circular_queue struct" | |
1464 | depends on LOCKDEP | |
1465 | range 10 30 | |
1466 | default 12 | |
1467 | help | |
1468 | Try increasing this value if you hit "lockdep bfs error:-1" warning due to __cq_enqueue() failure. | |
1469 | ||
4d9f34ad IM |
1470 | config DEBUG_LOCKDEP |
1471 | bool "Lock dependency engine debugging" | |
517e7aa5 | 1472 | depends on DEBUG_KERNEL && LOCKDEP |
997acaf6 | 1473 | select DEBUG_IRQFLAGS |
4d9f34ad IM |
1474 | help |
1475 | If you say Y here, the lock dependency engine will do | |
1476 | additional runtime checks to debug itself, at the price | |
1477 | of more runtime overhead. | |
1478 | ||
d902db1e FW |
1479 | config DEBUG_ATOMIC_SLEEP |
1480 | bool "Sleep inside atomic section checking" | |
e8f7c70f | 1481 | select PREEMPT_COUNT |
1da177e4 | 1482 | depends on DEBUG_KERNEL |
87a4c375 | 1483 | depends on !ARCH_NO_PREEMPT |
1da177e4 LT |
1484 | help |
1485 | If you say Y here, various routines which may sleep will become very | |
d902db1e FW |
1486 | noisy if they are called inside atomic sections: when a spinlock is |
1487 | held, inside an rcu read side critical section, inside preempt disabled | |
1488 | sections, inside an interrupt, etc... | |
1da177e4 | 1489 | |
cae2ed9a IM |
1490 | config DEBUG_LOCKING_API_SELFTESTS |
1491 | bool "Locking API boot-time self-tests" | |
1492 | depends on DEBUG_KERNEL | |
1493 | help | |
1494 | Say Y here if you want the kernel to run a short self-test during | |
1495 | bootup. The self-test checks whether common types of locking bugs | |
1496 | are detected by debugging mechanisms or not. (if you disable | |
9dbbc3b9 | 1497 | lock debugging then those bugs won't be detected of course.) |
cae2ed9a IM |
1498 | The following locking APIs are covered: spinlocks, rwlocks, |
1499 | mutexes and rwsems. | |
1500 | ||
0af3fe1e PM |
1501 | config LOCK_TORTURE_TEST |
1502 | tristate "torture tests for locking" | |
1503 | depends on DEBUG_KERNEL | |
1504 | select TORTURE_TEST | |
0af3fe1e PM |
1505 | help |
1506 | This option provides a kernel module that runs torture tests | |
1507 | on kernel locking primitives. The kernel module may be built | |
1508 | after the fact on the running kernel to be tested, if desired. | |
1509 | ||
1510 | Say Y here if you want kernel locking-primitive torture tests | |
1511 | to be built into the kernel. | |
1512 | Say M if you want these torture tests to build as a module. | |
1513 | Say N if you are unsure. | |
1514 | ||
f2a5fec1 CW |
1515 | config WW_MUTEX_SELFTEST |
1516 | tristate "Wait/wound mutex selftests" | |
1517 | help | |
1518 | This option provides a kernel module that runs tests on the | |
1519 | on the struct ww_mutex locking API. | |
1520 | ||
1521 | It is recommended to enable DEBUG_WW_MUTEX_SLOWPATH in conjunction | |
1522 | with this test harness. | |
1523 | ||
1524 | Say M if you want these self tests to build as a module. | |
1525 | Say N if you are unsure. | |
1526 | ||
e9d338a0 PM |
1527 | config SCF_TORTURE_TEST |
1528 | tristate "torture tests for smp_call_function*()" | |
1529 | depends on DEBUG_KERNEL | |
1530 | select TORTURE_TEST | |
1531 | help | |
1532 | This option provides a kernel module that runs torture tests | |
1533 | on the smp_call_function() family of primitives. The kernel | |
1534 | module may be built after the fact on the running kernel to | |
1535 | be tested, if desired. | |
1536 | ||
35feb604 PM |
1537 | config CSD_LOCK_WAIT_DEBUG |
1538 | bool "Debugging for csd_lock_wait(), called from smp_call_function*()" | |
1539 | depends on DEBUG_KERNEL | |
1540 | depends on 64BIT | |
1541 | default n | |
1542 | help | |
1543 | This option enables debug prints when CPUs are slow to respond | |
1544 | to the smp_call_function*() IPI wrappers. These debug prints | |
1545 | include the IPI handler function currently executing (if any) | |
1546 | and relevant stack traces. | |
1547 | ||
3c5b9039 DW |
1548 | choice |
1549 | prompt "Lock debugging: prove subsystem device_lock() correctness" | |
1550 | depends on PROVE_LOCKING | |
1551 | help | |
1552 | For subsystems that have instrumented their usage of the device_lock() | |
1553 | with nested annotations, enable lock dependency checking. The locking | |
1554 | hierarchy 'subclass' identifiers are not compatible across | |
1555 | sub-systems, so only one can be enabled at a time. | |
1556 | ||
1557 | config PROVE_NVDIMM_LOCKING | |
1558 | bool "NVDIMM" | |
1559 | depends on LIBNVDIMM | |
1560 | help | |
1561 | Enable lockdep to validate nd_device_lock() usage. | |
1562 | ||
1563 | config PROVE_CXL_LOCKING | |
1564 | bool "CXL" | |
1565 | depends on CXL_BUS | |
1566 | help | |
1567 | Enable lockdep to validate cxl_device_lock() usage. | |
1568 | ||
1569 | endchoice | |
1570 | ||
9eade16b | 1571 | endmenu # lock debugging |
8637c099 | 1572 | |
9eade16b | 1573 | config TRACE_IRQFLAGS |
ed004953 | 1574 | depends on TRACE_IRQFLAGS_SUPPORT |
9eade16b | 1575 | bool |
5ca43f6c | 1576 | help |
9eade16b DH |
1577 | Enables hooks to interrupt enabling and disabling for |
1578 | either tracing or lock debugging. | |
5ca43f6c | 1579 | |
ed004953 | 1580 | config TRACE_IRQFLAGS_NMI |
1581 | def_bool y | |
1582 | depends on TRACE_IRQFLAGS | |
1583 | depends on TRACE_IRQFLAGS_NMI_SUPPORT | |
1584 | ||
997acaf6 MR |
1585 | config DEBUG_IRQFLAGS |
1586 | bool "Debug IRQ flag manipulation" | |
1587 | help | |
1588 | Enables checks for potentially unsafe enabling or disabling of | |
1589 | interrupts, such as calling raw_local_irq_restore() when interrupts | |
1590 | are enabled. | |
1591 | ||
8637c099 | 1592 | config STACKTRACE |
0c38e1fe | 1593 | bool "Stack backtrace support" |
8637c099 | 1594 | depends on STACKTRACE_SUPPORT |
0c38e1fe DJ |
1595 | help |
1596 | This option causes the kernel to create a /proc/pid/stack for | |
1597 | every process, showing its current stack trace. | |
1598 | It is also used by various kernel debugging features that require | |
1599 | stack trace generation. | |
5ca43f6c | 1600 | |
eecabf56 TT |
1601 | config WARN_ALL_UNSEEDED_RANDOM |
1602 | bool "Warn for all uses of unseeded randomness" | |
1603 | default n | |
d06bfd19 JD |
1604 | help |
1605 | Some parts of the kernel contain bugs relating to their use of | |
1606 | cryptographically secure random numbers before it's actually possible | |
1607 | to generate those numbers securely. This setting ensures that these | |
1608 | flaws don't go unnoticed, by enabling a message, should this ever | |
1609 | occur. This will allow people with obscure setups to know when things | |
1610 | are going wrong, so that they might contact developers about fixing | |
1611 | it. | |
1612 | ||
eecabf56 TT |
1613 | Unfortunately, on some models of some architectures getting |
1614 | a fully seeded CRNG is extremely difficult, and so this can | |
1615 | result in dmesg getting spammed for a surprisingly long | |
1616 | time. This is really bad from a security perspective, and | |
1617 | so architecture maintainers really need to do what they can | |
1618 | to get the CRNG seeded sooner after the system is booted. | |
4c5d114e | 1619 | However, since users cannot do anything actionable to |
eecabf56 TT |
1620 | address this, by default the kernel will issue only a single |
1621 | warning for the first use of unseeded randomness. | |
1622 | ||
1623 | Say Y here if you want to receive warnings for all uses of | |
1624 | unseeded randomness. This will be of use primarily for | |
4c5d114e | 1625 | those developers interested in improving the security of |
eecabf56 TT |
1626 | Linux kernels running on their architecture (or |
1627 | subarchitecture). | |
d06bfd19 | 1628 | |
1da177e4 LT |
1629 | config DEBUG_KOBJECT |
1630 | bool "kobject debugging" | |
1631 | depends on DEBUG_KERNEL | |
1632 | help | |
1633 | If you say Y here, some extra kobject debugging messages will be sent | |
aca52c39 | 1634 | to the syslog. |
1da177e4 | 1635 | |
c817a67e RK |
1636 | config DEBUG_KOBJECT_RELEASE |
1637 | bool "kobject release debugging" | |
2a999aa0 | 1638 | depends on DEBUG_OBJECTS_TIMERS |
c817a67e RK |
1639 | help |
1640 | kobjects are reference counted objects. This means that their | |
1641 | last reference count put is not predictable, and the kobject can | |
1642 | live on past the point at which a driver decides to drop it's | |
1643 | initial reference to the kobject gained on allocation. An | |
1644 | example of this would be a struct device which has just been | |
1645 | unregistered. | |
1646 | ||
1647 | However, some buggy drivers assume that after such an operation, | |
1648 | the memory backing the kobject can be immediately freed. This | |
1649 | goes completely against the principles of a refcounted object. | |
1650 | ||
1651 | If you say Y here, the kernel will delay the release of kobjects | |
1652 | on the last reference count to improve the visibility of this | |
1653 | kind of kobject release bug. | |
1654 | ||
9b2a60c4 CM |
1655 | config HAVE_DEBUG_BUGVERBOSE |
1656 | bool | |
1657 | ||
3be5cbcd | 1658 | menu "Debug kernel data structures" |
1da177e4 | 1659 | |
199a9afc DJ |
1660 | config DEBUG_LIST |
1661 | bool "Debug linked list manipulation" | |
4520bcb2 | 1662 | depends on DEBUG_KERNEL || BUG_ON_DATA_CORRUPTION |
199a9afc DJ |
1663 | help |
1664 | Enable this to turn on extended checks in the linked-list | |
1665 | walking routines. | |
1666 | ||
1667 | If unsure, say N. | |
1668 | ||
8e18faea | 1669 | config DEBUG_PLIST |
b8cfff68 DS |
1670 | bool "Debug priority linked list manipulation" |
1671 | depends on DEBUG_KERNEL | |
1672 | help | |
1673 | Enable this to turn on extended checks in the priority-ordered | |
1674 | linked-list (plist) walking routines. This checks the entire | |
1675 | list multiple times during each manipulation. | |
1676 | ||
1677 | If unsure, say N. | |
1678 | ||
d6ec0842 JA |
1679 | config DEBUG_SG |
1680 | bool "Debug SG table operations" | |
1681 | depends on DEBUG_KERNEL | |
1682 | help | |
1683 | Enable this to turn on checks on scatter-gather tables. This can | |
1684 | help find problems with drivers that do not properly initialize | |
1685 | their sg tables. | |
1686 | ||
1687 | If unsure, say N. | |
1688 | ||
1b2439db AV |
1689 | config DEBUG_NOTIFIERS |
1690 | bool "Debug notifier call chains" | |
1691 | depends on DEBUG_KERNEL | |
1692 | help | |
1693 | Enable this to turn on sanity checking for notifier call chains. | |
1694 | This is most useful for kernel developers to make sure that | |
1695 | modules properly unregister themselves from notifier chains. | |
1696 | This is a relatively cheap check but if you care about maximum | |
1697 | performance, say N. | |
1698 | ||
3be5cbcd CD |
1699 | config BUG_ON_DATA_CORRUPTION |
1700 | bool "Trigger a BUG when data corruption is detected" | |
1701 | select DEBUG_LIST | |
1702 | help | |
1703 | Select this option if the kernel should BUG when it encounters | |
1704 | data corruption in kernel memory structures when they get checked | |
1705 | for validity. | |
1706 | ||
1707 | If unsure, say N. | |
1708 | ||
1709 | endmenu | |
1710 | ||
e0e81739 DH |
1711 | config DEBUG_CREDENTIALS |
1712 | bool "Debug credential management" | |
1713 | depends on DEBUG_KERNEL | |
1714 | help | |
1715 | Enable this to turn on some debug checking for credential | |
1716 | management. The additional code keeps track of the number of | |
1717 | pointers from task_structs to any given cred struct, and checks to | |
1718 | see that this number never exceeds the usage count of the cred | |
1719 | struct. | |
1720 | ||
1721 | Furthermore, if SELinux is enabled, this also checks that the | |
1722 | security pointer in the cred struct is never seen to be invalid. | |
1723 | ||
1724 | If unsure, say N. | |
1725 | ||
43a0a2a7 | 1726 | source "kernel/rcu/Kconfig.debug" |
2f03e3ca | 1727 | |
f303fccb TH |
1728 | config DEBUG_WQ_FORCE_RR_CPU |
1729 | bool "Force round-robin CPU selection for unbound work items" | |
1730 | depends on DEBUG_KERNEL | |
1731 | default n | |
1732 | help | |
1733 | Workqueue used to implicitly guarantee that work items queued | |
1734 | without explicit CPU specified are put on the local CPU. This | |
1735 | guarantee is no longer true and while local CPU is still | |
1736 | preferred work items may be put on foreign CPUs. Kernel | |
1737 | parameter "workqueue.debug_force_rr_cpu" is added to force | |
1738 | round-robin CPU selection to flush out usages which depend on the | |
1739 | now broken guarantee. This config option enables the debug | |
1740 | feature by default. When enabled, memory and cache locality will | |
1741 | be impacted. | |
1742 | ||
757c989b TG |
1743 | config CPU_HOTPLUG_STATE_CONTROL |
1744 | bool "Enable CPU hotplug state control" | |
1745 | depends on DEBUG_KERNEL | |
1746 | depends on HOTPLUG_CPU | |
1747 | default n | |
1748 | help | |
1749 | Allows to write steps between "offline" and "online" to the CPUs | |
1750 | sysfs target file so states can be stepped granular. This is a debug | |
1751 | option for now as the hotplug machinery cannot be stopped and | |
1752 | restarted at arbitrary points yet. | |
1753 | ||
1754 | Say N if your are unsure. | |
1755 | ||
09a74952 CD |
1756 | config LATENCYTOP |
1757 | bool "Latency measuring infrastructure" | |
1758 | depends on DEBUG_KERNEL | |
1759 | depends on STACKTRACE_SUPPORT | |
1760 | depends on PROC_FS | |
7d37cb2c | 1761 | depends on FRAME_POINTER || MIPS || PPC || S390 || MICROBLAZE || ARM || ARC || X86 |
09a74952 CD |
1762 | select KALLSYMS |
1763 | select KALLSYMS_ALL | |
1764 | select STACKTRACE | |
1765 | select SCHEDSTATS | |
09a74952 CD |
1766 | help |
1767 | Enable this option if you want to use the LatencyTOP tool | |
1768 | to find out which userspace is blocking on what kernel operations. | |
1769 | ||
1770 | source "kernel/trace/Kconfig" | |
1771 | ||
1772 | config PROVIDE_OHCI1394_DMA_INIT | |
1773 | bool "Remote debugging over FireWire early on boot" | |
1774 | depends on PCI && X86 | |
1775 | help | |
1776 | If you want to debug problems which hang or crash the kernel early | |
1777 | on boot and the crashing machine has a FireWire port, you can use | |
1778 | this feature to remotely access the memory of the crashed machine | |
1779 | over FireWire. This employs remote DMA as part of the OHCI1394 | |
1780 | specification which is now the standard for FireWire controllers. | |
1781 | ||
1782 | With remote DMA, you can monitor the printk buffer remotely using | |
1783 | firescope and access all memory below 4GB using fireproxy from gdb. | |
1784 | Even controlling a kernel debugger is possible using remote DMA. | |
1785 | ||
1786 | Usage: | |
1787 | ||
1788 | If ohci1394_dma=early is used as boot parameter, it will initialize | |
1789 | all OHCI1394 controllers which are found in the PCI config space. | |
1790 | ||
1791 | As all changes to the FireWire bus such as enabling and disabling | |
1792 | devices cause a bus reset and thereby disable remote DMA for all | |
1793 | devices, be sure to have the cable plugged and FireWire enabled on | |
1794 | the debugging host before booting the debug target for debugging. | |
1795 | ||
1796 | This code (~1k) is freed after boot. By then, the firewire stack | |
1797 | in charge of the OHCI-1394 controllers should be used instead. | |
1798 | ||
a74e2a22 | 1799 | See Documentation/core-api/debugging-via-ohci1394.rst for more information. |
09a74952 | 1800 | |
045f6d79 CD |
1801 | source "samples/Kconfig" |
1802 | ||
1803 | config ARCH_HAS_DEVMEM_IS_ALLOWED | |
1804 | bool | |
1805 | ||
1806 | config STRICT_DEVMEM | |
1807 | bool "Filter access to /dev/mem" | |
1808 | depends on MMU && DEVMEM | |
527701ed | 1809 | depends on ARCH_HAS_DEVMEM_IS_ALLOWED || GENERIC_LIB_DEVMEM_IS_ALLOWED |
045f6d79 CD |
1810 | default y if PPC || X86 || ARM64 |
1811 | help | |
1812 | If this option is disabled, you allow userspace (root) access to all | |
1813 | of memory, including kernel and userspace memory. Accidental | |
1814 | access to this is obviously disastrous, but specific access can | |
1815 | be used by people debugging the kernel. Note that with PAT support | |
1816 | enabled, even in this case there are restrictions on /dev/mem | |
1817 | use due to the cache aliasing requirements. | |
1818 | ||
1819 | If this option is switched on, and IO_STRICT_DEVMEM=n, the /dev/mem | |
1820 | file only allows userspace access to PCI space and the BIOS code and | |
1821 | data regions. This is sufficient for dosemu and X and all common | |
1822 | users of /dev/mem. | |
1823 | ||
1824 | If in doubt, say Y. | |
1825 | ||
1826 | config IO_STRICT_DEVMEM | |
1827 | bool "Filter I/O access to /dev/mem" | |
1828 | depends on STRICT_DEVMEM | |
1829 | help | |
1830 | If this option is disabled, you allow userspace (root) access to all | |
1831 | io-memory regardless of whether a driver is actively using that | |
1832 | range. Accidental access to this is obviously disastrous, but | |
1833 | specific access can be used by people debugging kernel drivers. | |
1834 | ||
1835 | If this option is switched on, the /dev/mem file only allows | |
1836 | userspace access to *idle* io-memory ranges (see /proc/iomem) This | |
1837 | may break traditional users of /dev/mem (dosemu, legacy X, etc...) | |
1838 | if the driver using a given range cannot be disabled. | |
1839 | ||
1840 | If in doubt, say Y. | |
1841 | ||
1842 | menu "$(SRCARCH) Debugging" | |
1843 | ||
1844 | source "arch/$(SRCARCH)/Kconfig.debug" | |
1845 | ||
1846 | endmenu | |
1847 | ||
1848 | menu "Kernel Testing and Coverage" | |
1849 | ||
09a74952 CD |
1850 | source "lib/kunit/Kconfig" |
1851 | ||
8d438288 AM |
1852 | config NOTIFIER_ERROR_INJECTION |
1853 | tristate "Notifier error injection" | |
1854 | depends on DEBUG_KERNEL | |
1855 | select DEBUG_FS | |
1856 | help | |
e41e85cc | 1857 | This option provides the ability to inject artificial errors to |
8d438288 AM |
1858 | specified notifier chain callbacks. It is useful to test the error |
1859 | handling of notifier call chain failures. | |
1860 | ||
1861 | Say N if unsure. | |
1862 | ||
048b9c35 AM |
1863 | config PM_NOTIFIER_ERROR_INJECT |
1864 | tristate "PM notifier error injection module" | |
1865 | depends on PM && NOTIFIER_ERROR_INJECTION | |
1866 | default m if PM_DEBUG | |
1867 | help | |
e41e85cc | 1868 | This option provides the ability to inject artificial errors to |
048b9c35 AM |
1869 | PM notifier chain callbacks. It is controlled through debugfs |
1870 | interface /sys/kernel/debug/notifier-error-inject/pm | |
1871 | ||
1872 | If the notifier call chain should be failed with some events | |
1873 | notified, write the error code to "actions/<notifier event>/error". | |
1874 | ||
1875 | Example: Inject PM suspend error (-12 = -ENOMEM) | |
1876 | ||
1877 | # cd /sys/kernel/debug/notifier-error-inject/pm/ | |
1878 | # echo -12 > actions/PM_SUSPEND_PREPARE/error | |
1879 | # echo mem > /sys/power/state | |
1880 | bash: echo: write error: Cannot allocate memory | |
1881 | ||
1882 | To compile this code as a module, choose M here: the module will | |
1883 | be called pm-notifier-error-inject. | |
1884 | ||
1885 | If unsure, say N. | |
1886 | ||
d526e85f BH |
1887 | config OF_RECONFIG_NOTIFIER_ERROR_INJECT |
1888 | tristate "OF reconfig notifier error injection module" | |
1889 | depends on OF_DYNAMIC && NOTIFIER_ERROR_INJECTION | |
08dfb4dd | 1890 | help |
e41e85cc | 1891 | This option provides the ability to inject artificial errors to |
d526e85f | 1892 | OF reconfig notifier chain callbacks. It is controlled |
08dfb4dd | 1893 | through debugfs interface under |
d526e85f | 1894 | /sys/kernel/debug/notifier-error-inject/OF-reconfig/ |
08dfb4dd AM |
1895 | |
1896 | If the notifier call chain should be failed with some events | |
1897 | notified, write the error code to "actions/<notifier event>/error". | |
1898 | ||
1899 | To compile this code as a module, choose M here: the module will | |
e12a95f4 | 1900 | be called of-reconfig-notifier-error-inject. |
08dfb4dd AM |
1901 | |
1902 | If unsure, say N. | |
1903 | ||
02fff96a NA |
1904 | config NETDEV_NOTIFIER_ERROR_INJECT |
1905 | tristate "Netdev notifier error injection module" | |
1906 | depends on NET && NOTIFIER_ERROR_INJECTION | |
1907 | help | |
1908 | This option provides the ability to inject artificial errors to | |
1909 | netdevice notifier chain callbacks. It is controlled through debugfs | |
1910 | interface /sys/kernel/debug/notifier-error-inject/netdev | |
1911 | ||
1912 | If the notifier call chain should be failed with some events | |
1913 | notified, write the error code to "actions/<notifier event>/error". | |
1914 | ||
1915 | Example: Inject netdevice mtu change error (-22 = -EINVAL) | |
1916 | ||
1917 | # cd /sys/kernel/debug/notifier-error-inject/netdev | |
1918 | # echo -22 > actions/NETDEV_CHANGEMTU/error | |
1919 | # ip link set eth0 mtu 1024 | |
1920 | RTNETLINK answers: Invalid argument | |
1921 | ||
1922 | To compile this code as a module, choose M here: the module will | |
1923 | be called netdev-notifier-error-inject. | |
1924 | ||
1925 | If unsure, say N. | |
1926 | ||
f1b4bd06 MP |
1927 | config FUNCTION_ERROR_INJECTION |
1928 | def_bool y | |
1929 | depends on HAVE_FUNCTION_ERROR_INJECTION && KPROBES | |
1930 | ||
6ff1cb35 | 1931 | config FAULT_INJECTION |
1ab8509a AM |
1932 | bool "Fault-injection framework" |
1933 | depends on DEBUG_KERNEL | |
329409ae AM |
1934 | help |
1935 | Provide fault-injection framework. | |
1936 | For more details, see Documentation/fault-injection/. | |
6ff1cb35 | 1937 | |
8a8b6502 | 1938 | config FAILSLAB |
1ab8509a AM |
1939 | bool "Fault-injection capability for kmalloc" |
1940 | depends on FAULT_INJECTION | |
773ff60e | 1941 | depends on SLAB || SLUB |
8a8b6502 | 1942 | help |
1ab8509a | 1943 | Provide fault-injection capability for kmalloc. |
8a8b6502 | 1944 | |
933e312e | 1945 | config FAIL_PAGE_ALLOC |
29b46fa3 | 1946 | bool "Fault-injection capability for alloc_pages()" |
1ab8509a | 1947 | depends on FAULT_INJECTION |
933e312e | 1948 | help |
1ab8509a | 1949 | Provide fault-injection capability for alloc_pages(). |
933e312e | 1950 | |
2c739ced AL |
1951 | config FAULT_INJECTION_USERCOPY |
1952 | bool "Fault injection capability for usercopy functions" | |
1953 | depends on FAULT_INJECTION | |
1954 | help | |
1955 | Provides fault-injection capability to inject failures | |
1956 | in usercopy functions (copy_from_user(), get_user(), ...). | |
1957 | ||
c17bb495 | 1958 | config FAIL_MAKE_REQUEST |
86327d19 | 1959 | bool "Fault-injection capability for disk IO" |
581d4e28 | 1960 | depends on FAULT_INJECTION && BLOCK |
c17bb495 | 1961 | help |
1ab8509a | 1962 | Provide fault-injection capability for disk IO. |
c17bb495 | 1963 | |
581d4e28 | 1964 | config FAIL_IO_TIMEOUT |
f4d01439 | 1965 | bool "Fault-injection capability for faking disk interrupts" |
581d4e28 JA |
1966 | depends on FAULT_INJECTION && BLOCK |
1967 | help | |
1968 | Provide fault-injection capability on end IO handling. This | |
1969 | will make the block layer "forget" an interrupt as configured, | |
1970 | thus exercising the error handling. | |
1971 | ||
1972 | Only works with drivers that use the generic timeout handling, | |
9dbbc3b9 | 1973 | for others it won't do anything. |
581d4e28 | 1974 | |
ab51fbab DB |
1975 | config FAIL_FUTEX |
1976 | bool "Fault-injection capability for futexes" | |
1977 | select DEBUG_FS | |
1978 | depends on FAULT_INJECTION && FUTEX | |
1979 | help | |
1980 | Provide fault-injection capability for futexes. | |
1981 | ||
f1b4bd06 MP |
1982 | config FAULT_INJECTION_DEBUG_FS |
1983 | bool "Debugfs entries for fault-injection capabilities" | |
1984 | depends on FAULT_INJECTION && SYSFS && DEBUG_FS | |
1985 | help | |
1986 | Enable configuration of fault-injection capabilities via debugfs. | |
1987 | ||
4b1a29a7 MH |
1988 | config FAIL_FUNCTION |
1989 | bool "Fault-injection capability for functions" | |
1990 | depends on FAULT_INJECTION_DEBUG_FS && FUNCTION_ERROR_INJECTION | |
1991 | help | |
1992 | Provide function-based fault-injection capability. | |
1993 | This will allow you to override a specific function with a return | |
1994 | with given return value. As a result, function caller will see | |
1995 | an error value and have to handle it. This is useful to test the | |
1996 | error handling in various subsystems. | |
1997 | ||
f1b4bd06 MP |
1998 | config FAIL_MMC_REQUEST |
1999 | bool "Fault-injection capability for MMC IO" | |
2000 | depends on FAULT_INJECTION_DEBUG_FS && MMC | |
6ff1cb35 | 2001 | help |
f1b4bd06 MP |
2002 | Provide fault-injection capability for MMC IO. |
2003 | This will make the mmc core return data errors. This is | |
2004 | useful to test the error handling in the mmc block device | |
2005 | and to test how the mmc host driver handles retries from | |
2006 | the block device. | |
1df49008 | 2007 | |
c782af25 CL |
2008 | config FAIL_SUNRPC |
2009 | bool "Fault-injection capability for SunRPC" | |
2010 | depends on FAULT_INJECTION_DEBUG_FS && SUNRPC_DEBUG | |
2011 | help | |
2012 | Provide fault-injection capability for SunRPC and | |
2013 | its consumers. | |
2014 | ||
1df49008 AM |
2015 | config FAULT_INJECTION_STACKTRACE_FILTER |
2016 | bool "stacktrace filter for fault-injection capabilities" | |
2017 | depends on FAULT_INJECTION_DEBUG_FS && STACKTRACE_SUPPORT | |
6d690dca | 2018 | depends on !X86_64 |
1df49008 | 2019 | select STACKTRACE |
7d37cb2c | 2020 | depends on FRAME_POINTER || MIPS || PPC || S390 || MICROBLAZE || ARM || ARC || X86 |
1df49008 AM |
2021 | help |
2022 | Provide stacktrace filter for fault-injection capabilities | |
267c4025 | 2023 | |
09a74952 CD |
2024 | config ARCH_HAS_KCOV |
2025 | bool | |
cc3fa840 | 2026 | help |
09a74952 CD |
2027 | An architecture should select this when it can successfully |
2028 | build and run with CONFIG_KCOV. This typically requires | |
2029 | disabling instrumentation for some early boot code. | |
cc3fa840 | 2030 | |
09a74952 CD |
2031 | config CC_HAS_SANCOV_TRACE_PC |
2032 | def_bool $(cc-option,-fsanitize-coverage=trace-pc) | |
cc3fa840 | 2033 | |
cc3fa840 | 2034 | |
09a74952 CD |
2035 | config KCOV |
2036 | bool "Code coverage for fuzzing" | |
2037 | depends on ARCH_HAS_KCOV | |
2038 | depends on CC_HAS_SANCOV_TRACE_PC || GCC_PLUGINS | |
22102f45 | 2039 | depends on !ARCH_WANTS_NO_INSTR || HAVE_NOINSTR_HACK || \ |
bece04b5 | 2040 | GCC_VERSION >= 120000 || CLANG_VERSION >= 130000 |
09a74952 CD |
2041 | select DEBUG_FS |
2042 | select GCC_PLUGIN_SANCOV if !CC_HAS_SANCOV_TRACE_PC | |
22102f45 | 2043 | select OBJTOOL if HAVE_NOINSTR_HACK |
09a74952 CD |
2044 | help |
2045 | KCOV exposes kernel code coverage information in a form suitable | |
2046 | for coverage-guided fuzzing (randomized testing). | |
cc3fa840 | 2047 | |
09a74952 CD |
2048 | If RANDOMIZE_BASE is enabled, PC values will not be stable across |
2049 | different machines and across reboots. If you need stable PC values, | |
2050 | disable RANDOMIZE_BASE. | |
cc3fa840 | 2051 | |
09a74952 | 2052 | For more details, see Documentation/dev-tools/kcov.rst. |
cc3fa840 | 2053 | |
09a74952 CD |
2054 | config KCOV_ENABLE_COMPARISONS |
2055 | bool "Enable comparison operands collection by KCOV" | |
2056 | depends on KCOV | |
2057 | depends on $(cc-option,-fsanitize-coverage=trace-cmp) | |
2058 | help | |
2059 | KCOV also exposes operands of every comparison in the instrumented | |
2060 | code along with operand sizes and PCs of the comparison instructions. | |
2061 | These operands can be used by fuzzing engines to improve the quality | |
2062 | of fuzzing coverage. | |
cc3fa840 | 2063 | |
09a74952 CD |
2064 | config KCOV_INSTRUMENT_ALL |
2065 | bool "Instrument all code by default" | |
2066 | depends on KCOV | |
2067 | default y | |
2068 | help | |
2069 | If you are doing generic system call fuzzing (like e.g. syzkaller), | |
2070 | then you will want to instrument the whole kernel and you should | |
2071 | say y here. If you are doing more targeted fuzzing (like e.g. | |
2072 | filesystem fuzzing with AFL) then you will want to enable coverage | |
2073 | for more specific subsets of files, and should say n here. | |
84bc809e | 2074 | |
5ff3b30a AK |
2075 | config KCOV_IRQ_AREA_SIZE |
2076 | hex "Size of interrupt coverage collection area in words" | |
2077 | depends on KCOV | |
2078 | default 0x40000 | |
2079 | help | |
2080 | KCOV uses preallocated per-cpu areas to collect coverage from | |
2081 | soft interrupts. This specifies the size of those areas in the | |
2082 | number of unsigned long words. | |
2083 | ||
d3deafaa VL |
2084 | menuconfig RUNTIME_TESTING_MENU |
2085 | bool "Runtime Testing" | |
908009e8 | 2086 | def_bool y |
d3deafaa VL |
2087 | |
2088 | if RUNTIME_TESTING_MENU | |
881c5149 DH |
2089 | |
2090 | config LKDTM | |
2091 | tristate "Linux Kernel Dump Test Tool Module" | |
2092 | depends on DEBUG_FS | |
881c5149 DH |
2093 | help |
2094 | This module enables testing of the different dumping mechanisms by | |
2095 | inducing system failures at predefined crash points. | |
2096 | If you don't need it: say N | |
2097 | Choose M here to compile this code as a module. The module will be | |
2098 | called lkdtm. | |
2099 | ||
2100 | Documentation on how to use the module can be found in | |
10ffebbe | 2101 | Documentation/fault-injection/provoke-crashes.rst |
881c5149 DH |
2102 | |
2103 | config TEST_LIST_SORT | |
ebd09577 DL |
2104 | tristate "Linked list sorting test" if !KUNIT_ALL_TESTS |
2105 | depends on KUNIT | |
2106 | default KUNIT_ALL_TESTS | |
881c5149 DH |
2107 | help |
2108 | Enable this to turn on 'list_sort()' function test. This test is | |
e327fd7c GU |
2109 | executed only once during system boot (so affects only boot time), |
2110 | or at module load time. | |
881c5149 DH |
2111 | |
2112 | If unsure, say N. | |
2113 | ||
6e24628d IR |
2114 | config TEST_MIN_HEAP |
2115 | tristate "Min heap test" | |
2116 | depends on DEBUG_KERNEL || m | |
2117 | help | |
2118 | Enable this to turn on min heap function tests. This test is | |
2119 | executed only once during system boot (so affects only boot time), | |
2120 | or at module load time. | |
2121 | ||
2122 | If unsure, say N. | |
2123 | ||
c5adae95 | 2124 | config TEST_SORT |
36f33b56 DL |
2125 | tristate "Array-based sort test" if !KUNIT_ALL_TESTS |
2126 | depends on KUNIT | |
2127 | default KUNIT_ALL_TESTS | |
c5adae95 | 2128 | help |
5c4e6798 GU |
2129 | This option enables the self-test function of 'sort()' at boot, |
2130 | or at module load time. | |
c5adae95 KF |
2131 | |
2132 | If unsure, say N. | |
2133 | ||
5086ea4b MR |
2134 | config TEST_DIV64 |
2135 | tristate "64bit/32bit division and modulo test" | |
2136 | depends on DEBUG_KERNEL || m | |
2137 | help | |
2138 | Enable this to turn on 'do_div()' function test. This test is | |
2139 | executed only once during system boot (so affects only boot time), | |
2140 | or at module load time. | |
2141 | ||
2142 | If unsure, say N. | |
2143 | ||
881c5149 | 2144 | config KPROBES_SANITY_TEST |
e44e81c5 | 2145 | tristate "Kprobes sanity tests" |
881c5149 DH |
2146 | depends on DEBUG_KERNEL |
2147 | depends on KPROBES | |
e44e81c5 | 2148 | depends on KUNIT |
881c5149 DH |
2149 | help |
2150 | This option provides for testing basic kprobes functionality on | |
5a6cf77f | 2151 | boot. Samples of kprobe and kretprobe are inserted and |
881c5149 DH |
2152 | verified for functionality. |
2153 | ||
2154 | Say N if you are unsure. | |
2155 | ||
f4616fab MH |
2156 | config FPROBE_SANITY_TEST |
2157 | bool "Self test for fprobe" | |
2158 | depends on DEBUG_KERNEL | |
2159 | depends on FPROBE | |
2160 | depends on KUNIT=y | |
2161 | help | |
2162 | This option will enable testing the fprobe when the system boot. | |
2163 | A series of tests are made to verify that the fprobe is functioning | |
2164 | properly. | |
2165 | ||
2166 | Say N if you are unsure. | |
2167 | ||
881c5149 DH |
2168 | config BACKTRACE_SELF_TEST |
2169 | tristate "Self test for the backtrace code" | |
2170 | depends on DEBUG_KERNEL | |
881c5149 DH |
2171 | help |
2172 | This option provides a kernel module that can be used to test | |
2173 | the kernel stack backtrace code. This option is not useful | |
2174 | for distributions or general kernels, but only for kernel | |
2175 | developers working on architecture code. | |
2176 | ||
2177 | Note that if you want to also test saved backtraces, you will | |
2178 | have to enable STACKTRACE as well. | |
2179 | ||
2180 | Say N if you are unsure. | |
2181 | ||
914a7b50 ED |
2182 | config TEST_REF_TRACKER |
2183 | tristate "Self test for reference tracker" | |
2184 | depends on DEBUG_KERNEL && STACKTRACE_SUPPORT | |
2185 | select REF_TRACKER | |
2186 | help | |
2187 | This option provides a kernel module performing tests | |
2188 | using reference tracker infrastructure. | |
2189 | ||
2190 | Say N if you are unsure. | |
2191 | ||
910a742d ML |
2192 | config RBTREE_TEST |
2193 | tristate "Red-Black tree test" | |
7c993e11 | 2194 | depends on DEBUG_KERNEL |
910a742d ML |
2195 | help |
2196 | A benchmark measuring the performance of the rbtree library. | |
2197 | Also includes rbtree invariant checks. | |
2198 | ||
4b4f3acc FB |
2199 | config REED_SOLOMON_TEST |
2200 | tristate "Reed-Solomon library test" | |
2201 | depends on DEBUG_KERNEL || m | |
2202 | select REED_SOLOMON | |
2203 | select REED_SOLOMON_ENC16 | |
2204 | select REED_SOLOMON_DEC16 | |
2205 | help | |
2206 | This option enables the self-test function of rslib at boot, | |
2207 | or at module load time. | |
2208 | ||
2209 | If unsure, say N. | |
2210 | ||
fff3fd8a ML |
2211 | config INTERVAL_TREE_TEST |
2212 | tristate "Interval tree test" | |
0f789b67 | 2213 | depends on DEBUG_KERNEL |
a88cc108 | 2214 | select INTERVAL_TREE |
fff3fd8a ML |
2215 | help |
2216 | A benchmark measuring the performance of the interval tree library | |
2217 | ||
623fd807 GT |
2218 | config PERCPU_TEST |
2219 | tristate "Per cpu operations test" | |
2220 | depends on m && DEBUG_KERNEL | |
2221 | help | |
2222 | Enable this option to build test module which validates per-cpu | |
2223 | operations. | |
2224 | ||
2225 | If unsure, say N. | |
2226 | ||
881c5149 | 2227 | config ATOMIC64_SELFTEST |
55ded955 | 2228 | tristate "Perform an atomic64_t self-test" |
881c5149 | 2229 | help |
55ded955 GU |
2230 | Enable this option to test the atomic64_t functions at boot or |
2231 | at module load time. | |
881c5149 DH |
2232 | |
2233 | If unsure, say N. | |
2234 | ||
2235 | config ASYNC_RAID6_TEST | |
2236 | tristate "Self test for hardware accelerated raid6 recovery" | |
2237 | depends on ASYNC_RAID6_RECOV | |
2238 | select ASYNC_MEMCPY | |
a7f7f624 | 2239 | help |
881c5149 DH |
2240 | This is a one-shot self test that permutes through the |
2241 | recovery of all the possible two disk failure scenarios for a | |
2242 | N-disk array. Recovery is performed with the asynchronous | |
2243 | raid6 recovery routines, and will optionally use an offload | |
2244 | engine if one is available. | |
2245 | ||
2246 | If unsure, say N. | |
2247 | ||
64d1d77a AS |
2248 | config TEST_HEXDUMP |
2249 | tristate "Test functions located in the hexdump module at runtime" | |
2250 | ||
b2ff70a0 MC |
2251 | config STRING_SELFTEST |
2252 | tristate "Test string functions at runtime" | |
2253 | ||
881c5149 DH |
2254 | config TEST_STRING_HELPERS |
2255 | tristate "Test functions located in the string_helpers module at runtime" | |
2256 | ||
0b0600c8 TH |
2257 | config TEST_STRSCPY |
2258 | tristate "Test strscpy*() family of functions at runtime" | |
2259 | ||
881c5149 DH |
2260 | config TEST_KSTRTOX |
2261 | tristate "Test kstrto*() family of functions at runtime" | |
2262 | ||
707cc728 RV |
2263 | config TEST_PRINTF |
2264 | tristate "Test printf() family of functions at runtime" | |
2265 | ||
50f530e1 RF |
2266 | config TEST_SCANF |
2267 | tristate "Test scanf() family of functions at runtime" | |
2268 | ||
5fd003f5 DD |
2269 | config TEST_BITMAP |
2270 | tristate "Test bitmap_*() family of functions at runtime" | |
5fd003f5 DD |
2271 | help |
2272 | Enable this option to test the bitmap functions at boot. | |
2273 | ||
2274 | If unsure, say N. | |
2275 | ||
cfaff0e5 AS |
2276 | config TEST_UUID |
2277 | tristate "Test functions located in the uuid module at runtime" | |
2278 | ||
ad3d6c72 MW |
2279 | config TEST_XARRAY |
2280 | tristate "Test the XArray code at runtime" | |
2281 | ||
7e1e7763 | 2282 | config TEST_RHASHTABLE |
9d6dbe1b | 2283 | tristate "Perform selftest on resizable hash table" |
7e1e7763 TG |
2284 | help |
2285 | Enable this option to test the rhashtable functions at boot. | |
2286 | ||
2287 | If unsure, say N. | |
2288 | ||
88168bf3 IB |
2289 | config TEST_SIPHASH |
2290 | tristate "Perform selftest on siphash functions" | |
468a9428 | 2291 | help |
88168bf3 IB |
2292 | Enable this option to test the kernel's siphash (<linux/siphash.h>) hash |
2293 | functions on boot (or module load). | |
468a9428 GS |
2294 | |
2295 | This is intended to help people writing architecture-specific | |
2296 | optimized versions. If unsure, say N. | |
2297 | ||
8ab8ba38 MW |
2298 | config TEST_IDA |
2299 | tristate "Perform selftest on IDA functions" | |
2300 | ||
44091d29 JP |
2301 | config TEST_PARMAN |
2302 | tristate "Perform selftest on priority array manager" | |
44091d29 JP |
2303 | depends on PARMAN |
2304 | help | |
2305 | Enable this option to test priority array manager on boot | |
2306 | (or module load). | |
2307 | ||
2308 | If unsure, say N. | |
2309 | ||
6aed82de DL |
2310 | config TEST_IRQ_TIMINGS |
2311 | bool "IRQ timings selftest" | |
2312 | depends on IRQ_TIMINGS | |
2313 | help | |
2314 | Enable this option to test the irq timings code on boot. | |
2315 | ||
2316 | If unsure, say N. | |
2317 | ||
8a6f0b47 | 2318 | config TEST_LKM |
93e9ef83 | 2319 | tristate "Test module loading with 'hello world' module" |
93e9ef83 KC |
2320 | depends on m |
2321 | help | |
2322 | This builds the "test_module" module that emits "Hello, world" | |
2323 | on printk when loaded. It is designed to be used for basic | |
2324 | evaluation of the module loading subsystem (for example when | |
2325 | validating module verification). It lacks any extra dependencies, | |
2326 | and will not normally be loaded by the system unless explicitly | |
2327 | requested by name. | |
2328 | ||
2329 | If unsure, say N. | |
2330 | ||
c348c163 | 2331 | config TEST_BITOPS |
6af132f3 | 2332 | tristate "Test module for compilation of bitops operations" |
c348c163 JB |
2333 | depends on m |
2334 | help | |
2335 | This builds the "test_bitops" module that is much like the | |
2336 | TEST_LKM module except that it does a basic exercise of the | |
6af132f3 WY |
2337 | set/clear_bit macros and get_count_order/long to make sure there are |
2338 | no compiler warnings from C=1 sparse checker or -Wextra | |
2339 | compilations. It has no dependencies and doesn't run or load unless | |
2340 | explicitly requested by name. for example: modprobe test_bitops. | |
c348c163 JB |
2341 | |
2342 | If unsure, say N. | |
2343 | ||
3f21a6b7 URS |
2344 | config TEST_VMALLOC |
2345 | tristate "Test module for stress/performance analysis of vmalloc allocator" | |
2346 | default n | |
2347 | depends on MMU | |
2348 | depends on m | |
2349 | help | |
2350 | This builds the "test_vmalloc" module that should be used for | |
2351 | stress and performance analysis. So, any new change for vmalloc | |
2352 | subsystem can be evaluated from performance and stability point | |
2353 | of view. | |
2354 | ||
2355 | If unsure, say N. | |
2356 | ||
3e2a4c18 KC |
2357 | config TEST_USER_COPY |
2358 | tristate "Test user/kernel boundary protections" | |
3e2a4c18 KC |
2359 | depends on m |
2360 | help | |
2361 | This builds the "test_user_copy" module that runs sanity checks | |
2362 | on the copy_to/from_user infrastructure, making sure basic | |
2363 | user/kernel boundary testing is working. If it fails to load, | |
2364 | a regression has been detected in the user/kernel memory boundary | |
2365 | protections. | |
2366 | ||
2367 | If unsure, say N. | |
2368 | ||
64a8946b AS |
2369 | config TEST_BPF |
2370 | tristate "Test BPF filter functionality" | |
98920ba6 | 2371 | depends on m && NET |
64a8946b AS |
2372 | help |
2373 | This builds the "test_bpf" module that runs various test vectors | |
2374 | against the BPF interpreter or BPF JIT compiler depending on the | |
2375 | current setting. This is in particular useful for BPF JIT compiler | |
2376 | development, but also to run regression tests against changes in | |
3c731eba AS |
2377 | the interpreter code. It also enables test stubs for eBPF maps and |
2378 | verifier used by user space verifier testsuite. | |
64a8946b AS |
2379 | |
2380 | If unsure, say N. | |
2381 | ||
509e56b3 MB |
2382 | config TEST_BLACKHOLE_DEV |
2383 | tristate "Test blackhole netdev functionality" | |
2384 | depends on m && NET | |
2385 | help | |
2386 | This builds the "test_blackhole_dev" module that validates the | |
2387 | data path through this blackhole netdev. | |
2388 | ||
2389 | If unsure, say N. | |
2390 | ||
dceeb3e7 | 2391 | config FIND_BIT_BENCHMARK |
4441fca0 | 2392 | tristate "Test find_bit functions" |
4441fca0 YN |
2393 | help |
2394 | This builds the "test_find_bit" module that measure find_*_bit() | |
2395 | functions performance. | |
2396 | ||
2397 | If unsure, say N. | |
2398 | ||
0a8adf58 KC |
2399 | config TEST_FIRMWARE |
2400 | tristate "Test firmware loading via userspace interface" | |
0a8adf58 KC |
2401 | depends on FW_LOADER |
2402 | help | |
2403 | This builds the "test_firmware" module that creates a userspace | |
2404 | interface for testing firmware loading. This can be used to | |
2405 | control the triggering of firmware loading without needing an | |
2406 | actual firmware-using device. The contents can be rechecked by | |
2407 | userspace. | |
2408 | ||
2409 | If unsure, say N. | |
2410 | ||
9308f2f9 LR |
2411 | config TEST_SYSCTL |
2412 | tristate "sysctl test driver" | |
9308f2f9 LR |
2413 | depends on PROC_SYSCTL |
2414 | help | |
2415 | This builds the "test_sysctl" module. This driver enables to test the | |
2416 | proc sysctl interfaces available to drivers safely without affecting | |
2417 | production knobs which might alter system functionality. | |
2418 | ||
2419 | If unsure, say N. | |
2420 | ||
d2585f51 VMI |
2421 | config BITFIELD_KUNIT |
2422 | tristate "KUnit test bitfield functions at runtime" | |
2423 | depends on KUNIT | |
2424 | help | |
2425 | Enable this option to test the bitfield functions at boot. | |
2426 | ||
2427 | KUnit tests run during boot and output the results to the debug log | |
2428 | in TAP format (http://testanything.org/). Only useful for kernel devs | |
2429 | running the KUnit test harness, and not intended for inclusion into a | |
2430 | production build. | |
2431 | ||
2432 | For more information on KUnit and unit tests in general please refer | |
2433 | to the KUnit documentation in Documentation/dev-tools/kunit/. | |
2434 | ||
2435 | If unsure, say N. | |
2436 | ||
0acc968f IB |
2437 | config HASH_KUNIT_TEST |
2438 | tristate "KUnit Test for integer hash functions" if !KUNIT_ALL_TESTS | |
2439 | depends on KUNIT | |
2440 | default KUNIT_ALL_TESTS | |
2441 | help | |
2442 | Enable this option to test the kernel's string (<linux/stringhash.h>), and | |
2443 | integer (<linux/hash.h>) hash functions on boot. | |
2444 | ||
2445 | KUnit tests run during boot and output the results to the debug log | |
2446 | in TAP format (https://testanything.org/). Only useful for kernel devs | |
2447 | running the KUnit test harness, and not intended for inclusion into a | |
2448 | production build. | |
2449 | ||
2450 | For more information on KUnit and unit tests in general please refer | |
2451 | to the KUnit documentation in Documentation/dev-tools/kunit/. | |
2452 | ||
2453 | This is intended to help people writing architecture-specific | |
2454 | optimized versions. If unsure, say N. | |
2455 | ||
5df38ca6 AS |
2456 | config RESOURCE_KUNIT_TEST |
2457 | tristate "KUnit test for resource API" | |
2458 | depends on KUNIT | |
2459 | help | |
2460 | This builds the resource API unit test. | |
2461 | Tests the logic of API provided by resource.c and ioport.h. | |
2462 | For more information on KUnit and unit tests in general please refer | |
2463 | to the KUnit documentation in Documentation/dev-tools/kunit/. | |
2464 | ||
2465 | If unsure, say N. | |
2466 | ||
2cb80dbb | 2467 | config SYSCTL_KUNIT_TEST |
5f215aab | 2468 | tristate "KUnit test for sysctl" if !KUNIT_ALL_TESTS |
2cb80dbb | 2469 | depends on KUNIT |
5f215aab | 2470 | default KUNIT_ALL_TESTS |
2cb80dbb IZ |
2471 | help |
2472 | This builds the proc sysctl unit test, which runs on boot. | |
2473 | Tests the API contract and implementation correctness of sysctl. | |
2474 | For more information on KUnit and unit tests in general please refer | |
2475 | to the KUnit documentation in Documentation/dev-tools/kunit/. | |
2476 | ||
2477 | If unsure, say N. | |
2478 | ||
ea2dd7c0 | 2479 | config LIST_KUNIT_TEST |
5f215aab | 2480 | tristate "KUnit Test for Kernel Linked-list structures" if !KUNIT_ALL_TESTS |
ea2dd7c0 | 2481 | depends on KUNIT |
5f215aab | 2482 | default KUNIT_ALL_TESTS |
ea2dd7c0 DG |
2483 | help |
2484 | This builds the linked list KUnit test suite. | |
2485 | It tests that the API and basic functionality of the list_head type | |
2486 | and associated macros. | |
2487 | ||
2488 | KUnit tests run during boot and output the results to the debug log | |
d89775fc | 2489 | in TAP format (https://testanything.org/). Only useful for kernel devs |
ea2dd7c0 DG |
2490 | running the KUnit test harness, and not intended for inclusion into a |
2491 | production build. | |
2492 | ||
2493 | For more information on KUnit and unit tests in general please refer | |
2494 | to the KUnit documentation in Documentation/dev-tools/kunit/. | |
2495 | ||
2496 | If unsure, say N. | |
2497 | ||
33d599f0 MV |
2498 | config LINEAR_RANGES_TEST |
2499 | tristate "KUnit test for linear_ranges" | |
2500 | depends on KUNIT | |
2501 | select LINEAR_RANGES | |
2502 | help | |
2503 | This builds the linear_ranges unit test, which runs on boot. | |
2504 | Tests the linear_ranges logic correctness. | |
2505 | For more information on KUnit and unit tests in general please refer | |
7546861a AS |
2506 | to the KUnit documentation in Documentation/dev-tools/kunit/. |
2507 | ||
2508 | If unsure, say N. | |
2509 | ||
2510 | config CMDLINE_KUNIT_TEST | |
2511 | tristate "KUnit test for cmdline API" | |
2512 | depends on KUNIT | |
2513 | help | |
2514 | This builds the cmdline API unit test. | |
2515 | Tests the logic of API provided by cmdline.c. | |
2516 | For more information on KUnit and unit tests in general please refer | |
33d599f0 MV |
2517 | to the KUnit documentation in Documentation/dev-tools/kunit/. |
2518 | ||
2519 | If unsure, say N. | |
2520 | ||
6d511020 RF |
2521 | config BITS_TEST |
2522 | tristate "KUnit test for bits.h" | |
2523 | depends on KUNIT | |
2524 | help | |
2525 | This builds the bits unit test. | |
2526 | Tests the logic of macros defined in bits.h. | |
2527 | For more information on KUnit and unit tests in general please refer | |
2528 | to the KUnit documentation in Documentation/dev-tools/kunit/. | |
2529 | ||
2530 | If unsure, say N. | |
2531 | ||
1f9f78b1 OG |
2532 | config SLUB_KUNIT_TEST |
2533 | tristate "KUnit test for SLUB cache error detection" if !KUNIT_ALL_TESTS | |
2534 | depends on SLUB_DEBUG && KUNIT | |
2535 | default KUNIT_ALL_TESTS | |
2536 | help | |
2537 | This builds SLUB allocator unit test. | |
2538 | Tests SLUB cache debugging functionality. | |
2539 | For more information on KUnit and unit tests in general please refer | |
2540 | to the KUnit documentation in Documentation/dev-tools/kunit/. | |
2541 | ||
2542 | If unsure, say N. | |
2543 | ||
b6c75c4a TP |
2544 | config RATIONAL_KUNIT_TEST |
2545 | tristate "KUnit test for rational.c" if !KUNIT_ALL_TESTS | |
8ba739ed | 2546 | depends on KUNIT && RATIONAL |
b6c75c4a TP |
2547 | default KUNIT_ALL_TESTS |
2548 | help | |
2549 | This builds the rational math unit test. | |
2550 | For more information on KUnit and unit tests in general please refer | |
2551 | to the KUnit documentation in Documentation/dev-tools/kunit/. | |
2552 | ||
2553 | If unsure, say N. | |
2554 | ||
bb95ebbe KC |
2555 | config MEMCPY_KUNIT_TEST |
2556 | tristate "Test memcpy(), memmove(), and memset() functions at runtime" if !KUNIT_ALL_TESTS | |
2557 | depends on KUNIT | |
2558 | default KUNIT_ALL_TESTS | |
2559 | help | |
2560 | Builds unit tests for memcpy(), memmove(), and memset() functions. | |
2561 | For more information on KUnit and unit tests in general please refer | |
2562 | to the KUnit documentation in Documentation/dev-tools/kunit/. | |
2563 | ||
2564 | If unsure, say N. | |
2565 | ||
617f55e2 KC |
2566 | config OVERFLOW_KUNIT_TEST |
2567 | tristate "Test check_*_overflow() functions at runtime" if !KUNIT_ALL_TESTS | |
2568 | depends on KUNIT | |
2569 | default KUNIT_ALL_TESTS | |
2570 | help | |
2571 | Builds unit tests for the check_*_overflow(), size_*(), allocation, and | |
2572 | related functions. | |
2573 | ||
2574 | For more information on KUnit and unit tests in general please refer | |
2575 | to the KUnit documentation in Documentation/dev-tools/kunit/. | |
2576 | ||
2577 | If unsure, say N. | |
2578 | ||
02788ebc KC |
2579 | config STACKINIT_KUNIT_TEST |
2580 | tristate "Test level of stack variable initialization" if !KUNIT_ALL_TESTS | |
2581 | depends on KUNIT | |
2582 | default KUNIT_ALL_TESTS | |
2583 | help | |
2584 | Test if the kernel is zero-initializing stack variables and | |
2585 | padding. Coverage is controlled by compiler flags, | |
2586 | CONFIG_INIT_STACK_ALL_PATTERN, CONFIG_INIT_STACK_ALL_ZERO, | |
2587 | CONFIG_GCC_PLUGIN_STRUCTLEAK, CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF, | |
2588 | or CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL. | |
2589 | ||
e704f93a DR |
2590 | config TEST_UDELAY |
2591 | tristate "udelay test driver" | |
e704f93a DR |
2592 | help |
2593 | This builds the "udelay_test" module that helps to make sure | |
2594 | that udelay() is working properly. | |
2595 | ||
2596 | If unsure, say N. | |
2597 | ||
2bf9e0ab IM |
2598 | config TEST_STATIC_KEYS |
2599 | tristate "Test static keys" | |
579e1acb JB |
2600 | depends on m |
2601 | help | |
2bf9e0ab | 2602 | Test the static key interfaces. |
579e1acb JB |
2603 | |
2604 | If unsure, say N. | |
2605 | ||
d9c6a72d LR |
2606 | config TEST_KMOD |
2607 | tristate "kmod stress tester" | |
d9c6a72d | 2608 | depends on m |
d9c6a72d | 2609 | depends on NETDEVICES && NET_CORE && INET # for TUN |
ae3d6a32 | 2610 | depends on BLOCK |
bbd2e05f | 2611 | depends on PAGE_SIZE_LESS_THAN_256KB # for BTRFS |
d9c6a72d LR |
2612 | select TEST_LKM |
2613 | select XFS_FS | |
2614 | select TUN | |
2615 | select BTRFS_FS | |
2616 | help | |
2617 | Test the kernel's module loading mechanism: kmod. kmod implements | |
2618 | support to load modules using the Linux kernel's usermode helper. | |
2619 | This test provides a series of tests against kmod. | |
2620 | ||
2621 | Although technically you can either build test_kmod as a module or | |
2622 | into the kernel we disallow building it into the kernel since | |
2623 | it stress tests request_module() and this will very likely cause | |
2624 | some issues by taking over precious threads available from other | |
2625 | module load requests, ultimately this could be fatal. | |
2626 | ||
2627 | To run tests run: | |
2628 | ||
2629 | tools/testing/selftests/kmod/kmod.sh --help | |
2630 | ||
2631 | If unsure, say N. | |
2632 | ||
e4dace36 FF |
2633 | config TEST_DEBUG_VIRTUAL |
2634 | tristate "Test CONFIG_DEBUG_VIRTUAL feature" | |
2635 | depends on DEBUG_VIRTUAL | |
2636 | help | |
2637 | Test the kernel's ability to detect incorrect calls to | |
2638 | virt_to_phys() done against the non-linear part of the | |
2639 | kernel's virtual address map. | |
2640 | ||
2641 | If unsure, say N. | |
2642 | ||
ce76d938 AS |
2643 | config TEST_MEMCAT_P |
2644 | tristate "Test memcat_p() helper function" | |
2645 | help | |
2646 | Test the memcat_p() helper for correctly merging two | |
2647 | pointer arrays together. | |
2648 | ||
2649 | If unsure, say N. | |
2650 | ||
a2818ee4 JL |
2651 | config TEST_LIVEPATCH |
2652 | tristate "Test livepatching" | |
2653 | default n | |
bae05437 | 2654 | depends on DYNAMIC_DEBUG |
a2818ee4 JL |
2655 | depends on LIVEPATCH |
2656 | depends on m | |
2657 | help | |
2658 | Test kernel livepatching features for correctness. The tests will | |
2659 | load test modules that will be livepatched in various scenarios. | |
2660 | ||
2661 | To run all the livepatching tests: | |
2662 | ||
2663 | make -C tools/testing/selftests TARGETS=livepatch run_tests | |
2664 | ||
2665 | Alternatively, individual tests may be invoked: | |
2666 | ||
2667 | tools/testing/selftests/livepatch/test-callbacks.sh | |
2668 | tools/testing/selftests/livepatch/test-livepatch.sh | |
2669 | tools/testing/selftests/livepatch/test-shadow-vars.sh | |
2670 | ||
2671 | If unsure, say N. | |
2672 | ||
0a020d41 JP |
2673 | config TEST_OBJAGG |
2674 | tristate "Perform selftest on object aggreration manager" | |
2675 | default n | |
2676 | depends on OBJAGG | |
2677 | help | |
2678 | Enable this option to test object aggregation manager on boot | |
2679 | (or module load). | |
2680 | ||
5015a300 AP |
2681 | config TEST_MEMINIT |
2682 | tristate "Test heap/page initialization" | |
2683 | help | |
2684 | Test if the kernel is zero-initializing heap and page allocations. | |
2685 | This can be useful to test init_on_alloc and init_on_free features. | |
2686 | ||
2687 | If unsure, say N. | |
2688 | ||
b2ef9f5a RC |
2689 | config TEST_HMM |
2690 | tristate "Test HMM (Heterogeneous Memory Management)" | |
2691 | depends on TRANSPARENT_HUGEPAGE | |
2692 | depends on DEVICE_PRIVATE | |
2693 | select HMM_MIRROR | |
2694 | select MMU_NOTIFIER | |
2695 | help | |
2696 | This is a pseudo device driver solely for testing HMM. | |
2697 | Say M here if you want to build the HMM test module. | |
2698 | Doing so will allow you to run tools/testing/selftest/vm/hmm-tests. | |
2699 | ||
2700 | If unsure, say N. | |
2701 | ||
e320d301 MWO |
2702 | config TEST_FREE_PAGES |
2703 | tristate "Test freeing pages" | |
2704 | help | |
2705 | Test that a memory leak does not occur due to a race between | |
2706 | freeing a block of pages and a speculative page reference. | |
2707 | Loading this module is safe if your kernel has the bug fixed. | |
2708 | If the bug is not fixed, it will leak gigabytes of memory and | |
2709 | probably OOM your system. | |
2710 | ||
4185b3b9 PA |
2711 | config TEST_FPU |
2712 | tristate "Test floating point operations in kernel space" | |
2713 | depends on X86 && !KCOV_INSTRUMENT_ALL | |
2714 | help | |
2715 | Enable this option to add /sys/kernel/debug/selftest_helpers/test_fpu | |
2716 | which will trigger a sequence of floating point operations. This is used | |
2717 | for self-testing floating point control register setting in | |
2718 | kernel_fpu_begin(). | |
2719 | ||
2720 | If unsure, say N. | |
2721 | ||
1253b9b8 PM |
2722 | config TEST_CLOCKSOURCE_WATCHDOG |
2723 | tristate "Test clocksource watchdog in kernel space" | |
2724 | depends on CLOCKSOURCE_WATCHDOG | |
2725 | help | |
2726 | Enable this option to create a kernel module that will trigger | |
2727 | a test of the clocksource watchdog. This module may be loaded | |
2728 | via modprobe or insmod in which case it will run upon being | |
2729 | loaded, or it may be built in, in which case it will run | |
2730 | shortly after boot. | |
2731 | ||
2732 | If unsure, say N. | |
2733 | ||
d3deafaa | 2734 | endif # RUNTIME_TESTING_MENU |
cc3fa840 | 2735 | |
dce44566 AK |
2736 | config ARCH_USE_MEMTEST |
2737 | bool | |
2738 | help | |
2739 | An architecture should select this when it uses early_memtest() | |
2740 | during boot process. | |
2741 | ||
cc3fa840 RD |
2742 | config MEMTEST |
2743 | bool "Memtest" | |
dce44566 | 2744 | depends on ARCH_USE_MEMTEST |
a7f7f624 | 2745 | help |
cc3fa840 | 2746 | This option adds a kernel parameter 'memtest', which allows memtest |
dce44566 | 2747 | to be set and executed. |
cc3fa840 RD |
2748 | memtest=0, mean disabled; -- default |
2749 | memtest=1, mean do 1 test pattern; | |
2750 | ... | |
2751 | memtest=17, mean do 17 test patterns. | |
2752 | If you are unsure how to answer this question, answer N. | |
2753 | ||
21266be9 | 2754 | |
06ec64b8 | 2755 | |
af9ca6f9 BB |
2756 | config HYPERV_TESTING |
2757 | bool "Microsoft Hyper-V driver testing" | |
2758 | default n | |
2759 | depends on HYPERV && DEBUG_FS | |
2760 | help | |
2761 | Select this option to enable Hyper-V vmbus testing. | |
2762 | ||
045f6d79 CD |
2763 | endmenu # "Kernel Testing and Coverage" |
2764 | ||
75442fb0 MCC |
2765 | source "Documentation/Kconfig" |
2766 | ||
06ec64b8 | 2767 | endmenu # Kernel hacking |