1 # SPDX-License-Identifier: GPL-2.0-only
4 menu "printk and dmesg options"
7 bool "Show timing information on printks"
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.
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.
18 The behavior is also controlled by the kernel command line
19 parameter printk.time=1. See Documentation/admin-guide/kernel-parameters.rst
22 bool "Show caller information on printks"
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)
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.
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
38 config STACKTRACE_BUILD_ID
39 bool "Show build ID information in stacktraces"
42 Selecting this option adds build ID information for symbols in
43 stacktraces printed with the printk format '%p[SR]b'.
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.
49 config CONSOLE_LOGLEVEL_DEFAULT
50 int "Default console loglevel (1-15)"
54 Default loglevel to determine what will be printed on the console.
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.
60 Note: This does not affect the log level of un-prefixed printk()
61 usage in the kernel. That is controlled by the MESSAGE_LOGLEVEL_DEFAULT
64 config CONSOLE_LOGLEVEL_QUIET
65 int "quiet console loglevel (1-15)"
69 loglevel to use when "quiet" is passed on the kernel commandline.
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>"
75 config MESSAGE_LOGLEVEL_DEFAULT
76 int "Default message log level (1-7)"
80 Default log level for printk statements with no specified priority.
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
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.
90 config BOOT_PRINTK_DELAY
91 bool "Delay each boot printk message by N milliseconds"
92 depends on DEBUG_KERNEL && PRINTK && GENERIC_CALIBRATE_DELAY
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,
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.
109 bool "Enable dynamic printk() support"
112 depends on (DEBUG_FS || PROC_FS)
113 select DYNAMIC_DEBUG_CORE
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%.
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.
130 Dynamic debugging is controlled via the 'dynamic_debug/control' file,
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.
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:
138 filename:lineno [module]function flags format
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
144 flags : '=p' means the line is turned 'on' for printing
145 format : the format used for the debug statement
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"
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
161 // enable all the messages in file svcsock.c
162 nullarbor:~ # echo -n 'file svcsock.c +p' >
163 <debugfs>/dynamic_debug/control
165 // enable all the messages in the NFS server module
166 nullarbor:~ # echo -n 'module nfsd +p' >
167 <debugfs>/dynamic_debug/control
169 // enable all 12 messages in the function svc_process()
170 nullarbor:~ # echo -n 'func svc_process +p' >
171 <debugfs>/dynamic_debug/control
173 // disable all 12 messages in the function svc_process()
174 nullarbor:~ # echo -n 'func svc_process -p' >
175 <debugfs>/dynamic_debug/control
177 See Documentation/admin-guide/dynamic-debug-howto.rst for additional
180 config DYNAMIC_DEBUG_CORE
181 bool "Enable core function of dynamic debug support"
183 depends on (DEBUG_FS || PROC_FS)
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.
191 config SYMBOLIC_ERRNAME
192 bool "Support symbolic error names in printf"
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.
200 config DEBUG_BUGVERBOSE
201 bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT
202 depends on BUG && (GENERIC_BUG || HAVE_DEBUG_BUGVERBOSE)
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.
209 endmenu # "printk and dmesg options"
212 bool "Kernel debugging"
214 Say Y here if you are developing drivers or trying to debug and
215 identify kernel problems.
218 bool "Miscellaneous debug code"
220 depends on DEBUG_KERNEL
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.
225 menu "Compile-time checks and compiler options"
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.
234 # Clang is known to generate .{s,u}leb128 with symbol deltas with DWARF5, which
235 # some targets may not support: https://sourceware.org/bugzilla/show_bug.cgi?id=27215
236 config AS_HAS_NON_CONST_LEB128
237 def_bool $(as-instr,.uleb128 .Lexpr_end4 - .Lexpr_start3\n.Lexpr_start3:\n.Lexpr_end4:)
240 prompt "Debug information"
241 depends on DEBUG_KERNEL
243 Selecting something other than "None" results in a kernel image
244 that will include debugging info resulting in a larger kernel image.
245 This adds debug symbols to the kernel and modules (gcc -g), and
246 is needed if you intend to use kernel crashdump or binary object
247 tools like crash, kgdb, LKCD, gdb, etc on the kernel.
249 Choose which version of DWARF debug info to emit. If unsure,
250 select "Toolchain default".
252 config DEBUG_INFO_NONE
253 bool "Disable debug information"
255 Do not build the kernel with debugging information, which will
256 result in a faster and smaller build.
258 config DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
259 bool "Rely on the toolchain's implicit default DWARF version"
261 depends on !CC_IS_CLANG || AS_IS_LLVM || CLANG_VERSION < 140000 || (AS_IS_GNU && AS_VERSION >= 23502 && AS_HAS_NON_CONST_LEB128)
263 The implicit default version of DWARF debug info produced by a
264 toolchain changes over time.
266 This can break consumers of the debug info that haven't upgraded to
267 support newer revisions, and prevent testing newer versions, but
268 those should be less common scenarios.
270 config DEBUG_INFO_DWARF4
271 bool "Generate DWARF Version 4 debuginfo"
273 depends on !CC_IS_CLANG || AS_IS_LLVM || (AS_IS_GNU && AS_VERSION >= 23502)
275 Generate DWARF v4 debug info. This requires gcc 4.5+, binutils 2.35.2
276 if using clang without clang's integrated assembler, and gdb 7.0+.
278 If you have consumers of DWARF debug info that are not ready for
279 newer revisions of DWARF, you may wish to choose this or have your
282 config DEBUG_INFO_DWARF5
283 bool "Generate DWARF Version 5 debuginfo"
285 depends on !CC_IS_CLANG || AS_IS_LLVM || (AS_IS_GNU && AS_VERSION >= 23502 && AS_HAS_NON_CONST_LEB128)
287 Generate DWARF v5 debug info. Requires binutils 2.35.2, gcc 5.0+ (gcc
288 5.0+ accepts the -gdwarf-5 flag but only had partial support for some
289 draft features until 7.0), and gdb 8.0+.
291 Changes to the structure of debug info in Version 5 allow for around
292 15-18% savings in resulting image and debug info section sizes as
293 compared to DWARF Version 4. DWARF Version 5 standardizes previous
294 extensions such as accelerators for symbol indexing and the format
295 for fission (.dwo/.dwp) files. Users may not want to select this
296 config if they rely on tooling that has not yet been updated to
297 support DWARF Version 5.
299 endchoice # "Debug information"
303 config DEBUG_INFO_REDUCED
304 bool "Reduce debugging information"
306 If you say Y here gcc is instructed to generate less debugging
307 information for structure types. This means that tools that
308 need full debugging information (like kgdb or systemtap) won't
309 be happy. But if you merely need debugging information to
310 resolve line numbers there is no loss. Advantage is that
311 build directory object sizes shrink dramatically over a full
312 DEBUG_INFO build and compile times are reduced too.
313 Only works with newer gcc versions.
316 prompt "Compressed Debug information"
318 Compress the resulting debug info. Results in smaller debug info sections,
319 but requires that consumers are able to decompress the results.
321 If unsure, choose DEBUG_INFO_COMPRESSED_NONE.
323 config DEBUG_INFO_COMPRESSED_NONE
324 bool "Don't compress debug information"
326 Don't compress debug info sections.
328 config DEBUG_INFO_COMPRESSED_ZLIB
329 bool "Compress debugging information with zlib"
330 depends on $(cc-option,-gz=zlib)
331 depends on $(ld-option,--compress-debug-sections=zlib)
333 Compress the debug information using zlib. Requires GCC 5.0+ or Clang
334 5.0+, binutils 2.26+, and zlib.
336 Users of dpkg-deb via scripts/package/builddeb may find an increase in
337 size of their debug .deb packages with this config set, due to the
338 debug info being compressed with zlib, then the object files being
339 recompressed with a different compression scheme. But this is still
340 preferable to setting $KDEB_COMPRESS to "none" which would be even
343 config DEBUG_INFO_COMPRESSED_ZSTD
344 bool "Compress debugging information with zstd"
345 depends on $(cc-option,-gz=zstd)
346 depends on $(ld-option,--compress-debug-sections=zstd)
348 Compress the debug information using zstd. This may provide better
349 compression than zlib, for about the same time costs, but requires newer
350 toolchain support. Requires GCC 13.0+ or Clang 16.0+, binutils 2.40+, and
353 endchoice # "Compressed Debug information"
355 config DEBUG_INFO_SPLIT
356 bool "Produce split debuginfo in .dwo files"
357 depends on $(cc-option,-gsplit-dwarf)
358 # RISC-V linker relaxation + -gsplit-dwarf has issues with LLVM and GCC
360 # https://github.com/llvm/llvm-project/issues/56642
361 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99090
362 depends on !RISCV || GCC_VERSION >= 120000
364 Generate debug info into separate .dwo files. This significantly
365 reduces the build directory size for builds with DEBUG_INFO,
366 because it stores the information only once on disk in .dwo
367 files instead of multiple times in object files and executables.
368 In addition the debug information is also compressed.
370 Requires recent gcc (4.7+) and recent gdb/binutils.
371 Any tool that packages or reads debug information would need
372 to know about the .dwo files and include them.
373 Incompatible with older versions of ccache.
375 config DEBUG_INFO_BTF
376 bool "Generate BTF typeinfo"
377 depends on !DEBUG_INFO_SPLIT && !DEBUG_INFO_REDUCED
378 depends on !GCC_PLUGIN_RANDSTRUCT || COMPILE_TEST
379 depends on BPF_SYSCALL
380 depends on !DEBUG_INFO_DWARF5 || PAHOLE_VERSION >= 121
382 Generate deduplicated BTF type information from DWARF debug info.
383 Turning this on expects presence of pahole tool, which will convert
384 DWARF type info into equivalent deduplicated BTF type info.
386 config PAHOLE_HAS_SPLIT_BTF
387 def_bool PAHOLE_VERSION >= 119
389 config PAHOLE_HAS_BTF_TAG
390 def_bool PAHOLE_VERSION >= 123
391 depends on CC_IS_CLANG
393 Decide whether pahole emits btf_tag attributes (btf_type_tag and
394 btf_decl_tag) or not. Currently only clang compiler implements
395 these attributes, so make the config depend on CC_IS_CLANG.
397 config PAHOLE_HAS_LANG_EXCLUDE
398 def_bool PAHOLE_VERSION >= 124
400 Support for the --lang_exclude flag which makes pahole exclude
401 compilation units from the supplied language. Used in Kbuild to
402 omit Rust CUs which are not supported in version 1.24 of pahole,
403 otherwise it would emit malformed kernel and module binaries when
404 using DEBUG_INFO_BTF_MODULES.
406 config DEBUG_INFO_BTF_MODULES
408 depends on DEBUG_INFO_BTF && MODULES && PAHOLE_HAS_SPLIT_BTF
410 Generate compact split BTF type information for kernel modules.
412 config MODULE_ALLOW_BTF_MISMATCH
413 bool "Allow loading modules with non-matching BTF type info"
414 depends on DEBUG_INFO_BTF_MODULES
416 For modules whose split BTF does not match vmlinux, load without
417 BTF rather than refusing to load. The default behavior with
418 module BTF enabled is to reject modules with such mismatches;
419 this option will still load module BTF where possible but ignore
420 it when a mismatch is found.
423 bool "Provide GDB scripts for kernel debugging"
425 This creates the required links to GDB helper scripts in the
426 build directory. If you load vmlinux into gdb, the helper
427 scripts will be automatically imported by gdb as well, and
428 additional functions are available to analyze a Linux kernel
429 instance. See Documentation/dev-tools/gdb-kernel-debugging.rst
435 int "Warn for stack frames larger than"
438 default 2048 if GCC_PLUGIN_LATENT_ENTROPY
439 default 2048 if PARISC
440 default 1536 if (!64BIT && XTENSA)
441 default 1280 if KASAN && !64BIT
442 default 1024 if !64BIT
443 default 2048 if 64BIT
445 Tell the compiler to warn at build time for stack frames larger than this.
446 Setting this too low will cause a lot of warnings.
447 Setting it to 0 disables the warning.
449 config STRIP_ASM_SYMS
450 bool "Strip assembler-generated symbols during link"
453 Strip internal assembler-generated symbols during a link (symbols
454 that look like '.Lxxx') so they don't pollute the output of
455 get_wchan() and suchlike.
458 bool "Generate readable assembler code"
459 depends on DEBUG_KERNEL
462 Disable some compiler optimizations that tend to generate human unreadable
463 assembler output. This may make the kernel slightly slower, but it helps
464 to keep kernel developers who have to stare a lot at assembler listings
467 config HEADERS_INSTALL
468 bool "Install uapi headers to usr/include"
471 This option will install uapi headers (headers exported to user-space)
472 into the usr/include directory for use during the kernel build.
473 This is unneeded for building the kernel itself, but needed for some
474 user-space program samples. It is also needed by some features such
475 as uapi header sanity checks.
477 config DEBUG_SECTION_MISMATCH
478 bool "Enable full Section mismatch analysis"
481 The section mismatch analysis checks if there are illegal
482 references from one section to another section.
483 During linktime or runtime, some sections are dropped;
484 any use of code/data previously in these sections would
485 most likely result in an oops.
486 In the code, functions and variables are annotated with
487 __init,, etc. (see the full list in include/linux/init.h),
488 which results in the code/data being placed in specific sections.
489 The section mismatch analysis is always performed after a full
490 kernel build, and enabling this option causes the following
491 additional step to occur:
492 - Add the option -fno-inline-functions-called-once to gcc commands.
493 When inlining a function annotated with __init in a non-init
494 function, we would lose the section information and thus
495 the analysis would not catch the illegal reference.
496 This option tells gcc to inline less (but it does result in
499 config SECTION_MISMATCH_WARN_ONLY
500 bool "Make section mismatch errors non-fatal"
503 If you say N here, the build process will fail if there are any
504 section mismatch, instead of just throwing warnings.
508 config DEBUG_FORCE_FUNCTION_ALIGN_64B
509 bool "Force all function address 64B aligned"
510 depends on EXPERT && (X86_64 || ARM64 || PPC32 || PPC64 || ARC || RISCV || S390)
511 select FUNCTION_ALIGNMENT_64B
513 There are cases that a commit from one domain changes the function
514 address alignment of other domains, and cause magic performance
515 bump (regression or improvement). Enable this option will help to
516 verify if the bump is caused by function alignment changes, while
517 it will slightly increase the kernel size and affect icache usage.
519 It is mainly for debug and performance tuning use.
522 # Select this config option from the architecture Kconfig, if it
523 # is preferred to always offer frame pointers as a config
524 # option on the architecture (regardless of KERNEL_DEBUG):
526 config ARCH_WANT_FRAME_POINTERS
530 bool "Compile the kernel with frame pointers"
531 depends on DEBUG_KERNEL && (M68K || UML || SUPERH) || ARCH_WANT_FRAME_POINTERS
532 default y if (DEBUG_INFO && UML) || ARCH_WANT_FRAME_POINTERS
534 If you say Y here the resulting kernel image will be slightly
535 larger and slower, but it gives very useful debugging information
536 in case of kernel bugs. (precise oopses/stacktraces/warnings)
541 config STACK_VALIDATION
542 bool "Compile-time stack metadata validation"
543 depends on HAVE_STACK_VALIDATION && UNWINDER_FRAME_POINTER
547 Validate frame pointer rules at compile-time. This helps ensure that
548 runtime stack traces are more reliable.
550 For more information, see
551 tools/objtool/Documentation/objtool.txt.
553 config NOINSTR_VALIDATION
555 depends on HAVE_NOINSTR_VALIDATION && DEBUG_ENTRY
560 bool "Generate vmlinux.map file when linking"
563 Selecting this option will pass "-Map=vmlinux.map" to ld
564 when linking vmlinux. That file can be useful for verifying
565 and debugging magic section games, and for seeing which
566 pieces of code get eliminated with
567 CONFIG_LD_DEAD_CODE_DATA_ELIMINATION.
569 config DEBUG_FORCE_WEAK_PER_CPU
570 bool "Force weak per-cpu definitions"
571 depends on DEBUG_KERNEL
573 s390 and alpha require percpu variables in modules to be
574 defined weak to work around addressing range issue which
575 puts the following two restrictions on percpu variable
578 1. percpu symbols must be unique whether static or not
579 2. percpu variables can't be defined inside a function
581 To ensure that generic code follows the above rules, this
582 option forces all percpu variables to be defined as weak.
584 endmenu # "Compiler options"
586 menu "Generic Kernel Debugging Instruments"
589 bool "Magic SysRq key"
592 If you say Y here, you will have some control over the system even
593 if the system crashes for example during kernel debugging (e.g., you
594 will be able to flush the buffer cache to disk, reboot the system
595 immediately or dump some status information). This is accomplished
596 by pressing various keys while holding SysRq (Alt+PrintScreen). It
597 also works on a serial console (on PC hardware at least), if you
598 send a BREAK and then within 5 seconds a command keypress. The
599 keys are documented in <file:Documentation/admin-guide/sysrq.rst>.
600 Don't say Y unless you really know what this hack does.
602 config MAGIC_SYSRQ_DEFAULT_ENABLE
603 hex "Enable magic SysRq key functions by default"
604 depends on MAGIC_SYSRQ
607 Specifies which SysRq key functions are enabled by default.
608 This may be set to 1 or 0 to enable or disable them all, or
609 to a bitmask as described in Documentation/admin-guide/sysrq.rst.
611 config MAGIC_SYSRQ_SERIAL
612 bool "Enable magic SysRq key over serial"
613 depends on MAGIC_SYSRQ
616 Many embedded boards have a disconnected TTL level serial which can
617 generate some garbage that can lead to spurious false sysrq detects.
618 This option allows you to decide whether you want to enable the
621 config MAGIC_SYSRQ_SERIAL_SEQUENCE
622 string "Char sequence that enables magic SysRq over serial"
623 depends on MAGIC_SYSRQ_SERIAL
626 Specifies a sequence of characters that can follow BREAK to enable
627 SysRq on a serial console.
629 If unsure, leave an empty string and the option will not be enabled.
632 bool "Debug Filesystem"
634 debugfs is a virtual file system that kernel developers use to put
635 debugging files into. Enable this option to be able to read and
636 write to these files.
638 For detailed documentation on the debugfs API, see
639 Documentation/filesystems/.
644 prompt "Debugfs default access"
646 default DEBUG_FS_ALLOW_ALL
648 This selects the default access restrictions for debugfs.
649 It can be overridden with kernel command line option
650 debugfs=[on,no-mount,off]. The restrictions apply for API access
651 and filesystem registration.
653 config DEBUG_FS_ALLOW_ALL
656 No restrictions apply. Both API and filesystem registration
657 is on. This is the normal default operation.
659 config DEBUG_FS_DISALLOW_MOUNT
660 bool "Do not register debugfs as filesystem"
662 The API is open but filesystem is not loaded. Clients can still do
663 their work and read with debug tools that do not need
666 config DEBUG_FS_ALLOW_NONE
669 Access is off. Clients get -PERM when trying to create nodes in
670 debugfs tree and debugfs is not registered as a filesystem.
671 Client can then back-off or continue without debugfs access.
675 source "lib/Kconfig.kgdb"
676 source "lib/Kconfig.ubsan"
677 source "lib/Kconfig.kcsan"
681 menu "Networking Debugging"
683 source "net/Kconfig.debug"
685 endmenu # "Networking Debugging"
687 menu "Memory Debugging"
689 source "mm/Kconfig.debug"
692 bool "Debug object operations"
693 depends on DEBUG_KERNEL
695 If you say Y here, additional code will be inserted into the
696 kernel to track the life time of various objects and validate
697 the operations on those objects.
699 config DEBUG_OBJECTS_SELFTEST
700 bool "Debug objects selftest"
701 depends on DEBUG_OBJECTS
703 This enables the selftest of the object debug code.
705 config DEBUG_OBJECTS_FREE
706 bool "Debug objects in freed memory"
707 depends on DEBUG_OBJECTS
709 This enables checks whether a k/v free operation frees an area
710 which contains an object which has not been deactivated
711 properly. This can make kmalloc/kfree-intensive workloads
714 config DEBUG_OBJECTS_TIMERS
715 bool "Debug timer objects"
716 depends on DEBUG_OBJECTS
718 If you say Y here, additional code will be inserted into the
719 timer routines to track the life time of timer objects and
720 validate the timer operations.
722 config DEBUG_OBJECTS_WORK
723 bool "Debug work objects"
724 depends on DEBUG_OBJECTS
726 If you say Y here, additional code will be inserted into the
727 work queue routines to track the life time of work objects and
728 validate the work operations.
730 config DEBUG_OBJECTS_RCU_HEAD
731 bool "Debug RCU callbacks objects"
732 depends on DEBUG_OBJECTS
734 Enable this to turn on debugging of RCU list heads (call_rcu() usage).
736 config DEBUG_OBJECTS_PERCPU_COUNTER
737 bool "Debug percpu counter objects"
738 depends on DEBUG_OBJECTS
740 If you say Y here, additional code will be inserted into the
741 percpu counter routines to track the life time of percpu counter
742 objects and validate the percpu counter operations.
744 config DEBUG_OBJECTS_ENABLE_DEFAULT
745 int "debug_objects bootup default value (0-1)"
748 depends on DEBUG_OBJECTS
750 Debug objects boot parameter default value
752 config SHRINKER_DEBUG
753 bool "Enable shrinker debugging support"
756 Say Y to enable the shrinker debugfs interface which provides
757 visibility into the kernel memory shrinkers subsystem.
758 Disable it to avoid an extra memory footprint.
760 config DEBUG_STACK_USAGE
761 bool "Stack utilization instrumentation"
762 depends on DEBUG_KERNEL
764 Enables the display of the minimum amount of free stack which each
765 task has ever had available in the sysrq-T and sysrq-P debug output.
766 Also emits a message to dmesg when a process exits if that process
767 used more stack space than previously exiting processes.
769 This option will slow down process creation somewhat.
771 config SCHED_STACK_END_CHECK
772 bool "Detect stack corruption on calls to schedule()"
773 depends on DEBUG_KERNEL
776 This option checks for a stack overrun on calls to schedule().
777 If the stack end location is found to be over written always panic as
778 the content of the corrupted region can no longer be trusted.
779 This is to ensure no erroneous behaviour occurs which could result in
780 data corruption or a sporadic crash at a later stage once the region
781 is examined. The runtime overhead introduced is minimal.
783 config ARCH_HAS_DEBUG_VM_PGTABLE
786 An architecture should select this when it can successfully
787 build and run DEBUG_VM_PGTABLE.
789 config DEBUG_VM_IRQSOFF
790 def_bool DEBUG_VM && !PREEMPT_RT
794 depends on DEBUG_KERNEL
796 Enable this to turn on extended checks in the virtual-memory system
797 that may impact performance.
801 config DEBUG_VM_SHOOT_LAZIES
802 bool "Debug MMU_LAZY_TLB_SHOOTDOWN implementation"
804 depends on MMU_LAZY_TLB_SHOOTDOWN
806 Enable additional IPIs that ensure lazy tlb mm references are removed
807 before the mm is freed.
811 config DEBUG_VM_MAPLE_TREE
812 bool "Debug VM maple trees"
814 select DEBUG_MAPLE_TREE
816 Enable VM maple tree debugging information and extra validations.
821 bool "Debug VM red-black trees"
824 Enable VM red-black tree debugging information and extra validations.
828 config DEBUG_VM_PGFLAGS
829 bool "Debug page-flags operations"
832 Enables extra validation on page flags operations.
836 config DEBUG_VM_PGTABLE
837 bool "Debug arch page table for semantics compliance"
839 depends on ARCH_HAS_DEBUG_VM_PGTABLE
840 default y if DEBUG_VM
842 This option provides a debug method which can be used to test
843 architecture page table helper functions on various platforms in
844 verifying if they comply with expected generic MM semantics. This
845 will help architecture code in making sure that any changes or
846 new additions of these helpers still conform to expected
847 semantics of the generic MM. Platforms will have to opt in for
848 this through ARCH_HAS_DEBUG_VM_PGTABLE.
852 config ARCH_HAS_DEBUG_VIRTUAL
856 bool "Debug VM translations"
857 depends on DEBUG_KERNEL && ARCH_HAS_DEBUG_VIRTUAL
859 Enable some costly sanity checks in virtual to page code. This can
860 catch mistakes with virt_to_page() and friends.
864 config DEBUG_NOMMU_REGIONS
865 bool "Debug the global anon/private NOMMU mapping region tree"
866 depends on DEBUG_KERNEL && !MMU
868 This option causes the global tree of anonymous and private mapping
869 regions to be regularly checked for invalid topology.
871 config DEBUG_MEMORY_INIT
872 bool "Debug memory initialisation" if EXPERT
875 Enable this for additional checks during memory initialisation.
876 The sanity checks verify aspects of the VM such as the memory model
877 and other information provided by the architecture. Verbose
878 information will be printed at KERN_DEBUG loglevel depending
879 on the mminit_loglevel= command-line option.
883 config MEMORY_NOTIFIER_ERROR_INJECT
884 tristate "Memory hotplug notifier error injection module"
885 depends on MEMORY_HOTPLUG && NOTIFIER_ERROR_INJECTION
887 This option provides the ability to inject artificial errors to
888 memory hotplug notifier chain callbacks. It is controlled through
889 debugfs interface under /sys/kernel/debug/notifier-error-inject/memory
891 If the notifier call chain should be failed with some events
892 notified, write the error code to "actions/<notifier event>/error".
894 Example: Inject memory hotplug offline error (-12 == -ENOMEM)
896 # cd /sys/kernel/debug/notifier-error-inject/memory
897 # echo -12 > actions/MEM_GOING_OFFLINE/error
898 # echo offline > /sys/devices/system/memory/memoryXXX/state
899 bash: echo: write error: Cannot allocate memory
901 To compile this code as a module, choose M here: the module will
902 be called memory-notifier-error-inject.
906 config DEBUG_PER_CPU_MAPS
907 bool "Debug access to per_cpu maps"
908 depends on DEBUG_KERNEL
911 Say Y to verify that the per_cpu map being accessed has
912 been set up. This adds a fair amount of code to kernel memory
913 and decreases performance.
917 config DEBUG_KMAP_LOCAL
918 bool "Debug kmap_local temporary mappings"
919 depends on DEBUG_KERNEL && KMAP_LOCAL
921 This option enables additional error checking for the kmap_local
922 infrastructure. Disable for production use.
924 config ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP
927 config DEBUG_KMAP_LOCAL_FORCE_MAP
928 bool "Enforce kmap_local temporary mappings"
929 depends on DEBUG_KERNEL && ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP
931 select DEBUG_KMAP_LOCAL
933 This option enforces temporary mappings through the kmap_local
934 mechanism for non-highmem pages and on non-highmem systems.
935 Disable this for production systems!
938 bool "Highmem debugging"
939 depends on DEBUG_KERNEL && HIGHMEM
940 select DEBUG_KMAP_LOCAL_FORCE_MAP if ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP
941 select DEBUG_KMAP_LOCAL
943 This option enables additional error checking for high memory
944 systems. Disable for production systems.
946 config HAVE_DEBUG_STACKOVERFLOW
949 config DEBUG_STACKOVERFLOW
950 bool "Check for stack overflows"
951 depends on DEBUG_KERNEL && HAVE_DEBUG_STACKOVERFLOW
953 Say Y here if you want to check for overflows of kernel, IRQ
954 and exception stacks (if your architecture uses them). This
955 option will show detailed messages if free stack space drops
956 below a certain limit.
958 These kinds of bugs usually occur when call-chains in the
959 kernel get too deep, especially when interrupts are
962 Use this in cases where you see apparently random memory
963 corruption, especially if it appears in 'struct thread_info'
965 If in doubt, say "N".
967 source "lib/Kconfig.kasan"
968 source "lib/Kconfig.kfence"
969 source "lib/Kconfig.kmsan"
971 endmenu # "Memory Debugging"
974 bool "Debug shared IRQ handlers"
975 depends on DEBUG_KERNEL
977 Enable this to generate a spurious interrupt just before a shared
978 interrupt handler is deregistered (generating one when registering
979 is currently disabled). Drivers need to handle this correctly. Some
980 don't and need to be caught.
982 menu "Debug Oops, Lockups and Hangs"
987 Say Y here to enable the kernel to panic when it oopses. This
988 has the same effect as setting oops=panic on the kernel command
991 This feature is useful to ensure that the kernel does not do
992 anything erroneous after an oops which could result in data
993 corruption or other issues.
997 config PANIC_ON_OOPS_VALUE
1000 default 0 if !PANIC_ON_OOPS
1001 default 1 if PANIC_ON_OOPS
1003 config PANIC_TIMEOUT
1007 Set the timeout value (in seconds) until a reboot occurs when
1008 the kernel panics. If n = 0, then we wait forever. A timeout
1009 value n > 0 will wait n seconds before rebooting, while a timeout
1010 value n < 0 will reboot immediately.
1012 config LOCKUP_DETECTOR
1015 config SOFTLOCKUP_DETECTOR
1016 bool "Detect Soft Lockups"
1017 depends on DEBUG_KERNEL && !S390
1018 select LOCKUP_DETECTOR
1020 Say Y here to enable the kernel to act as a watchdog to detect
1023 Softlockups are bugs that cause the kernel to loop in kernel
1024 mode for more than 20 seconds, without giving other tasks a
1025 chance to run. The current stack trace is displayed upon
1026 detection and the system will stay locked up.
1028 config BOOTPARAM_SOFTLOCKUP_PANIC
1029 bool "Panic (Reboot) On Soft Lockups"
1030 depends on SOFTLOCKUP_DETECTOR
1032 Say Y here to enable the kernel to panic on "soft lockups",
1033 which are bugs that cause the kernel to loop in kernel
1034 mode for more than 20 seconds (configurable using the watchdog_thresh
1035 sysctl), without giving other tasks a chance to run.
1037 The panic can be used in combination with panic_timeout,
1038 to cause the system to reboot automatically after a
1039 lockup has been detected. This feature is useful for
1040 high-availability systems that have uptime guarantees and
1041 where a lockup must be resolved ASAP.
1045 config HAVE_HARDLOCKUP_DETECTOR_BUDDY
1051 # Global switch whether to build a hardlockup detector at all. It is available
1052 # only when the architecture supports at least one implementation. There are
1053 # two exceptions. The hardlockup detector is never enabled on:
1055 # s390: it reported many false positives there
1057 # sparc64: has a custom implementation which is not using the common
1058 # hardlockup command line options and sysctl interface.
1060 config HARDLOCKUP_DETECTOR
1061 bool "Detect Hard Lockups"
1062 depends on DEBUG_KERNEL && !S390 && !HARDLOCKUP_DETECTOR_SPARC64
1063 depends on HAVE_HARDLOCKUP_DETECTOR_PERF || HAVE_HARDLOCKUP_DETECTOR_BUDDY || HAVE_HARDLOCKUP_DETECTOR_ARCH
1064 imply HARDLOCKUP_DETECTOR_PERF
1065 imply HARDLOCKUP_DETECTOR_BUDDY
1066 imply HARDLOCKUP_DETECTOR_ARCH
1067 select LOCKUP_DETECTOR
1070 Say Y here to enable the kernel to act as a watchdog to detect
1073 Hardlockups are bugs that cause the CPU to loop in kernel mode
1074 for more than 10 seconds, without letting other interrupts have a
1075 chance to run. The current stack trace is displayed upon detection
1076 and the system will stay locked up.
1079 # Note that arch-specific variants are always preferred.
1081 config HARDLOCKUP_DETECTOR_PREFER_BUDDY
1082 bool "Prefer the buddy CPU hardlockup detector"
1083 depends on HARDLOCKUP_DETECTOR
1084 depends on HAVE_HARDLOCKUP_DETECTOR_PERF && HAVE_HARDLOCKUP_DETECTOR_BUDDY
1085 depends on !HAVE_HARDLOCKUP_DETECTOR_ARCH
1087 Say Y here to prefer the buddy hardlockup detector over the perf one.
1089 With the buddy detector, each CPU uses its softlockup hrtimer
1090 to check that the next CPU is processing hrtimer interrupts by
1091 verifying that a counter is increasing.
1093 This hardlockup detector is useful on systems that don't have
1094 an arch-specific hardlockup detector or if resources needed
1095 for the hardlockup detector are better used for other things.
1097 config HARDLOCKUP_DETECTOR_PERF
1099 depends on HARDLOCKUP_DETECTOR
1100 depends on HAVE_HARDLOCKUP_DETECTOR_PERF && !HARDLOCKUP_DETECTOR_PREFER_BUDDY
1101 depends on !HAVE_HARDLOCKUP_DETECTOR_ARCH
1102 select HARDLOCKUP_DETECTOR_COUNTS_HRTIMER
1104 config HARDLOCKUP_DETECTOR_BUDDY
1106 depends on HARDLOCKUP_DETECTOR
1107 depends on HAVE_HARDLOCKUP_DETECTOR_BUDDY
1108 depends on !HAVE_HARDLOCKUP_DETECTOR_PERF || HARDLOCKUP_DETECTOR_PREFER_BUDDY
1109 depends on !HAVE_HARDLOCKUP_DETECTOR_ARCH
1110 select HARDLOCKUP_DETECTOR_COUNTS_HRTIMER
1112 config HARDLOCKUP_DETECTOR_ARCH
1114 depends on HARDLOCKUP_DETECTOR
1115 depends on HAVE_HARDLOCKUP_DETECTOR_ARCH
1117 The arch-specific implementation of the hardlockup detector will
1121 # Both the "perf" and "buddy" hardlockup detectors count hrtimer
1122 # interrupts. This config enables functions managing this common code.
1124 config HARDLOCKUP_DETECTOR_COUNTS_HRTIMER
1126 select SOFTLOCKUP_DETECTOR
1129 # Enables a timestamp based low pass filter to compensate for perf based
1130 # hard lockup detection which runs too fast due to turbo modes.
1132 config HARDLOCKUP_CHECK_TIMESTAMP
1135 config BOOTPARAM_HARDLOCKUP_PANIC
1136 bool "Panic (Reboot) On Hard Lockups"
1137 depends on HARDLOCKUP_DETECTOR
1139 Say Y here to enable the kernel to panic on "hard lockups",
1140 which are bugs that cause the kernel to loop in kernel
1141 mode with interrupts disabled for more than 10 seconds (configurable
1142 using the watchdog_thresh sysctl).
1146 config DETECT_HUNG_TASK
1147 bool "Detect Hung Tasks"
1148 depends on DEBUG_KERNEL
1149 default SOFTLOCKUP_DETECTOR
1151 Say Y here to enable the kernel to detect "hung tasks",
1152 which are bugs that cause the task to be stuck in
1153 uninterruptible "D" state indefinitely.
1155 When a hung task is detected, the kernel will print the
1156 current stack trace (which you should report), but the
1157 task will stay in uninterruptible state. If lockdep is
1158 enabled then all held locks will also be reported. This
1159 feature has negligible overhead.
1161 config DEFAULT_HUNG_TASK_TIMEOUT
1162 int "Default timeout for hung task detection (in seconds)"
1163 depends on DETECT_HUNG_TASK
1166 This option controls the default timeout (in seconds) used
1167 to determine when a task has become non-responsive and should
1170 It can be adjusted at runtime via the kernel.hung_task_timeout_secs
1171 sysctl or by writing a value to
1172 /proc/sys/kernel/hung_task_timeout_secs.
1174 A timeout of 0 disables the check. The default is two minutes.
1175 Keeping the default should be fine in most cases.
1177 config BOOTPARAM_HUNG_TASK_PANIC
1178 bool "Panic (Reboot) On Hung Tasks"
1179 depends on DETECT_HUNG_TASK
1181 Say Y here to enable the kernel to panic on "hung tasks",
1182 which are bugs that cause the kernel to leave a task stuck
1183 in uninterruptible "D" state.
1185 The panic can be used in combination with panic_timeout,
1186 to cause the system to reboot automatically after a
1187 hung task has been detected. This feature is useful for
1188 high-availability systems that have uptime guarantees and
1189 where a hung tasks must be resolved ASAP.
1194 bool "Detect Workqueue Stalls"
1195 depends on DEBUG_KERNEL
1197 Say Y here to enable stall detection on workqueues. If a
1198 worker pool doesn't make forward progress on a pending work
1199 item for over a given amount of time, 30s by default, a
1200 warning message is printed along with dump of workqueue
1201 state. This can be configured through kernel parameter
1202 "workqueue.watchdog_thresh" and its sysfs counterpart.
1204 config WQ_CPU_INTENSIVE_REPORT
1205 bool "Report per-cpu work items which hog CPU for too long"
1206 depends on DEBUG_KERNEL
1208 Say Y here to enable reporting of concurrency-managed per-cpu work
1209 items that hog CPUs for longer than
1210 workqueue.cpu_intensive_thresh_us. Workqueue automatically
1211 detects and excludes them from concurrency management to prevent
1212 them from stalling other per-cpu work items. Occassional
1213 triggering may not necessarily indicate a problem. Repeated
1214 triggering likely indicates that the work item should be switched
1215 to use an unbound workqueue.
1218 tristate "Test module to generate lockups"
1221 This builds the "test_lockup" module that helps to make sure
1222 that watchdogs and lockup detectors are working properly.
1224 Depending on module parameters it could emulate soft or hard
1225 lockup, "hung task", or locking arbitrary lock for a long time.
1226 Also it could generate series of lockups with cooling-down periods.
1230 endmenu # "Debug lockups and hangs"
1232 menu "Scheduler Debugging"
1235 bool "Collect scheduler debugging info"
1236 depends on DEBUG_KERNEL && DEBUG_FS
1239 If you say Y here, the /sys/kernel/debug/sched file will be provided
1240 that can help debug the scheduler. The runtime overhead of this
1248 bool "Collect scheduler statistics"
1249 depends on DEBUG_KERNEL && PROC_FS
1252 If you say Y here, additional code will be inserted into the
1253 scheduler and related routines to collect statistics about
1254 scheduler behavior and provide them in /proc/schedstat. These
1255 stats may be useful for both tuning and debugging the scheduler
1256 If you aren't debugging the scheduler or trying to tune a specific
1257 application, you can say N to avoid the very slight overhead
1262 config DEBUG_TIMEKEEPING
1263 bool "Enable extra timekeeping sanity checking"
1265 This option will enable additional timekeeping sanity checks
1266 which may be helpful when diagnosing issues where timekeeping
1267 problems are suspected.
1269 This may include checks in the timekeeping hotpaths, so this
1270 option may have a (very small) performance impact to some
1275 config DEBUG_PREEMPT
1276 bool "Debug preemptible kernel"
1277 depends on DEBUG_KERNEL && PREEMPTION && TRACE_IRQFLAGS_SUPPORT
1279 If you say Y here then the kernel will use a debug variant of the
1280 commonly used smp_processor_id() function and will print warnings
1281 if kernel code uses it in a preemption-unsafe way. Also, the kernel
1282 will detect preemption count underflows.
1284 This option has potential to introduce high runtime overhead,
1285 depending on workload as it triggers debugging routines for each
1286 this_cpu operation. It should only be used for debugging purposes.
1288 menu "Lock Debugging (spinlocks, mutexes, etc...)"
1290 config LOCK_DEBUGGING_SUPPORT
1292 depends on TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT
1295 config PROVE_LOCKING
1296 bool "Lock debugging: prove locking correctness"
1297 depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT
1299 select DEBUG_SPINLOCK
1300 select DEBUG_MUTEXES if !PREEMPT_RT
1301 select DEBUG_RT_MUTEXES if RT_MUTEXES
1303 select DEBUG_WW_MUTEX_SLOWPATH
1304 select DEBUG_LOCK_ALLOC
1305 select PREEMPT_COUNT if !ARCH_NO_PREEMPT
1306 select TRACE_IRQFLAGS
1309 This feature enables the kernel to prove that all locking
1310 that occurs in the kernel runtime is mathematically
1311 correct: that under no circumstance could an arbitrary (and
1312 not yet triggered) combination of observed locking
1313 sequences (on an arbitrary number of CPUs, running an
1314 arbitrary number of tasks and interrupt contexts) cause a
1317 In short, this feature enables the kernel to report locking
1318 related deadlocks before they actually occur.
1320 The proof does not depend on how hard and complex a
1321 deadlock scenario would be to trigger: how many
1322 participant CPUs, tasks and irq-contexts would be needed
1323 for it to trigger. The proof also does not depend on
1324 timing: if a race and a resulting deadlock is possible
1325 theoretically (no matter how unlikely the race scenario
1326 is), it will be proven so and will immediately be
1327 reported by the kernel (once the event is observed that
1328 makes the deadlock theoretically possible).
1330 If a deadlock is impossible (i.e. the locking rules, as
1331 observed by the kernel, are mathematically correct), the
1332 kernel reports nothing.
1334 NOTE: this feature can also be enabled for rwlocks, mutexes
1335 and rwsems - in which case all dependencies between these
1336 different locking variants are observed and mapped too, and
1337 the proof of observed correctness is also maintained for an
1338 arbitrary combination of these separate locking variants.
1340 For more details, see Documentation/locking/lockdep-design.rst.
1342 config PROVE_RAW_LOCK_NESTING
1343 bool "Enable raw_spinlock - spinlock nesting checks"
1344 depends on PROVE_LOCKING
1347 Enable the raw_spinlock vs. spinlock nesting checks which ensure
1348 that the lock nesting rules for PREEMPT_RT enabled kernels are
1351 NOTE: There are known nesting problems. So if you enable this
1352 option expect lockdep splats until these problems have been fully
1353 addressed which is work in progress. This config switch allows to
1354 identify and analyze these problems. It will be removed and the
1355 check permanently enabled once the main issues have been fixed.
1357 If unsure, select N.
1360 bool "Lock usage statistics"
1361 depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT
1363 select DEBUG_SPINLOCK
1364 select DEBUG_MUTEXES if !PREEMPT_RT
1365 select DEBUG_RT_MUTEXES if RT_MUTEXES
1366 select DEBUG_LOCK_ALLOC
1369 This feature enables tracking lock contention points
1371 For more details, see Documentation/locking/lockstat.rst
1373 This also enables lock events required by "perf lock",
1375 If you want to use "perf lock", you also need to turn on
1376 CONFIG_EVENT_TRACING.
1378 CONFIG_LOCK_STAT defines "contended" and "acquired" lock events.
1379 (CONFIG_LOCKDEP defines "acquire" and "release" events.)
1381 config DEBUG_RT_MUTEXES
1382 bool "RT Mutex debugging, deadlock detection"
1383 depends on DEBUG_KERNEL && RT_MUTEXES
1385 This allows rt mutex semantics violations and rt mutex related
1386 deadlocks (lockups) to be detected and reported automatically.
1388 config DEBUG_SPINLOCK
1389 bool "Spinlock and rw-lock debugging: basic checks"
1390 depends on DEBUG_KERNEL
1391 select UNINLINE_SPIN_UNLOCK
1393 Say Y here and build SMP to catch missing spinlock initialization
1394 and certain other kinds of spinlock errors commonly made. This is
1395 best used in conjunction with the NMI watchdog so that spinlock
1396 deadlocks are also debuggable.
1398 config DEBUG_MUTEXES
1399 bool "Mutex debugging: basic checks"
1400 depends on DEBUG_KERNEL && !PREEMPT_RT
1402 This feature allows mutex semantics violations to be detected and
1405 config DEBUG_WW_MUTEX_SLOWPATH
1406 bool "Wait/wound mutex debugging: Slowpath testing"
1407 depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT
1408 select DEBUG_LOCK_ALLOC
1409 select DEBUG_SPINLOCK
1410 select DEBUG_MUTEXES if !PREEMPT_RT
1411 select DEBUG_RT_MUTEXES if PREEMPT_RT
1413 This feature enables slowpath testing for w/w mutex users by
1414 injecting additional -EDEADLK wound/backoff cases. Together with
1415 the full mutex checks enabled with (CONFIG_PROVE_LOCKING) this
1416 will test all possible w/w mutex interface abuse with the
1417 exception of simply not acquiring all the required locks.
1418 Note that this feature can introduce significant overhead, so
1419 it really should not be enabled in a production or distro kernel,
1420 even a debug kernel. If you are a driver writer, enable it. If
1421 you are a distro, do not.
1424 bool "RW Semaphore debugging: basic checks"
1425 depends on DEBUG_KERNEL
1427 This debugging feature allows mismatched rw semaphore locks
1428 and unlocks to be detected and reported.
1430 config DEBUG_LOCK_ALLOC
1431 bool "Lock debugging: detect incorrect freeing of live locks"
1432 depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT
1433 select DEBUG_SPINLOCK
1434 select DEBUG_MUTEXES if !PREEMPT_RT
1435 select DEBUG_RT_MUTEXES if RT_MUTEXES
1438 This feature will check whether any held lock (spinlock, rwlock,
1439 mutex or rwsem) is incorrectly freed by the kernel, via any of the
1440 memory-freeing routines (kfree(), kmem_cache_free(), free_pages(),
1441 vfree(), etc.), whether a live lock is incorrectly reinitialized via
1442 spin_lock_init()/mutex_init()/etc., or whether there is any lock
1443 held during task exit.
1447 depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT
1452 config LOCKDEP_SMALL
1456 int "Bitsize for MAX_LOCKDEP_ENTRIES"
1457 depends on LOCKDEP && !LOCKDEP_SMALL
1461 Try increasing this value if you hit "BUG: MAX_LOCKDEP_ENTRIES too low!" message.
1463 config LOCKDEP_CHAINS_BITS
1464 int "Bitsize for MAX_LOCKDEP_CHAINS"
1465 depends on LOCKDEP && !LOCKDEP_SMALL
1469 Try increasing this value if you hit "BUG: MAX_LOCKDEP_CHAINS too low!" message.
1471 config LOCKDEP_STACK_TRACE_BITS
1472 int "Bitsize for MAX_STACK_TRACE_ENTRIES"
1473 depends on LOCKDEP && !LOCKDEP_SMALL
1477 Try increasing this value if you hit "BUG: MAX_STACK_TRACE_ENTRIES too low!" message.
1479 config LOCKDEP_STACK_TRACE_HASH_BITS
1480 int "Bitsize for STACK_TRACE_HASH_SIZE"
1481 depends on LOCKDEP && !LOCKDEP_SMALL
1485 Try increasing this value if you need large STACK_TRACE_HASH_SIZE.
1487 config LOCKDEP_CIRCULAR_QUEUE_BITS
1488 int "Bitsize for elements in circular_queue struct"
1493 Try increasing this value if you hit "lockdep bfs error:-1" warning due to __cq_enqueue() failure.
1495 config DEBUG_LOCKDEP
1496 bool "Lock dependency engine debugging"
1497 depends on DEBUG_KERNEL && LOCKDEP
1498 select DEBUG_IRQFLAGS
1500 If you say Y here, the lock dependency engine will do
1501 additional runtime checks to debug itself, at the price
1502 of more runtime overhead.
1504 config DEBUG_ATOMIC_SLEEP
1505 bool "Sleep inside atomic section checking"
1506 select PREEMPT_COUNT
1507 depends on DEBUG_KERNEL
1508 depends on !ARCH_NO_PREEMPT
1510 If you say Y here, various routines which may sleep will become very
1511 noisy if they are called inside atomic sections: when a spinlock is
1512 held, inside an rcu read side critical section, inside preempt disabled
1513 sections, inside an interrupt, etc...
1515 config DEBUG_LOCKING_API_SELFTESTS
1516 bool "Locking API boot-time self-tests"
1517 depends on DEBUG_KERNEL
1519 Say Y here if you want the kernel to run a short self-test during
1520 bootup. The self-test checks whether common types of locking bugs
1521 are detected by debugging mechanisms or not. (if you disable
1522 lock debugging then those bugs won't be detected of course.)
1523 The following locking APIs are covered: spinlocks, rwlocks,
1526 config LOCK_TORTURE_TEST
1527 tristate "torture tests for locking"
1528 depends on DEBUG_KERNEL
1531 This option provides a kernel module that runs torture tests
1532 on kernel locking primitives. The kernel module may be built
1533 after the fact on the running kernel to be tested, if desired.
1535 Say Y here if you want kernel locking-primitive torture tests
1536 to be built into the kernel.
1537 Say M if you want these torture tests to build as a module.
1538 Say N if you are unsure.
1540 config WW_MUTEX_SELFTEST
1541 tristate "Wait/wound mutex selftests"
1543 This option provides a kernel module that runs tests on the
1544 on the struct ww_mutex locking API.
1546 It is recommended to enable DEBUG_WW_MUTEX_SLOWPATH in conjunction
1547 with this test harness.
1549 Say M if you want these self tests to build as a module.
1550 Say N if you are unsure.
1552 config SCF_TORTURE_TEST
1553 tristate "torture tests for smp_call_function*()"
1554 depends on DEBUG_KERNEL
1557 This option provides a kernel module that runs torture tests
1558 on the smp_call_function() family of primitives. The kernel
1559 module may be built after the fact on the running kernel to
1560 be tested, if desired.
1562 config CSD_LOCK_WAIT_DEBUG
1563 bool "Debugging for csd_lock_wait(), called from smp_call_function*()"
1564 depends on DEBUG_KERNEL
1568 This option enables debug prints when CPUs are slow to respond
1569 to the smp_call_function*() IPI wrappers. These debug prints
1570 include the IPI handler function currently executing (if any)
1571 and relevant stack traces.
1573 config CSD_LOCK_WAIT_DEBUG_DEFAULT
1574 bool "Default csd_lock_wait() debugging on at boot time"
1575 depends on CSD_LOCK_WAIT_DEBUG
1579 This option causes the csdlock_debug= kernel boot parameter to
1580 default to 1 (basic debugging) instead of 0 (no debugging).
1582 endmenu # lock debugging
1584 config TRACE_IRQFLAGS
1585 depends on TRACE_IRQFLAGS_SUPPORT
1588 Enables hooks to interrupt enabling and disabling for
1589 either tracing or lock debugging.
1591 config TRACE_IRQFLAGS_NMI
1593 depends on TRACE_IRQFLAGS
1594 depends on TRACE_IRQFLAGS_NMI_SUPPORT
1596 config NMI_CHECK_CPU
1597 bool "Debugging for CPUs failing to respond to backtrace requests"
1598 depends on DEBUG_KERNEL
1602 Enables debug prints when a CPU fails to respond to a given
1603 backtrace NMI. These prints provide some reasons why a CPU
1604 might legitimately be failing to respond, for example, if it
1605 is offline of if ignore_nmis is set.
1607 config DEBUG_IRQFLAGS
1608 bool "Debug IRQ flag manipulation"
1610 Enables checks for potentially unsafe enabling or disabling of
1611 interrupts, such as calling raw_local_irq_restore() when interrupts
1615 bool "Stack backtrace support"
1616 depends on STACKTRACE_SUPPORT
1618 This option causes the kernel to create a /proc/pid/stack for
1619 every process, showing its current stack trace.
1620 It is also used by various kernel debugging features that require
1621 stack trace generation.
1623 config WARN_ALL_UNSEEDED_RANDOM
1624 bool "Warn for all uses of unseeded randomness"
1627 Some parts of the kernel contain bugs relating to their use of
1628 cryptographically secure random numbers before it's actually possible
1629 to generate those numbers securely. This setting ensures that these
1630 flaws don't go unnoticed, by enabling a message, should this ever
1631 occur. This will allow people with obscure setups to know when things
1632 are going wrong, so that they might contact developers about fixing
1635 Unfortunately, on some models of some architectures getting
1636 a fully seeded CRNG is extremely difficult, and so this can
1637 result in dmesg getting spammed for a surprisingly long
1638 time. This is really bad from a security perspective, and
1639 so architecture maintainers really need to do what they can
1640 to get the CRNG seeded sooner after the system is booted.
1641 However, since users cannot do anything actionable to
1642 address this, by default this option is disabled.
1644 Say Y here if you want to receive warnings for all uses of
1645 unseeded randomness. This will be of use primarily for
1646 those developers interested in improving the security of
1647 Linux kernels running on their architecture (or
1650 config DEBUG_KOBJECT
1651 bool "kobject debugging"
1652 depends on DEBUG_KERNEL
1654 If you say Y here, some extra kobject debugging messages will be sent
1657 config DEBUG_KOBJECT_RELEASE
1658 bool "kobject release debugging"
1659 depends on DEBUG_OBJECTS_TIMERS
1661 kobjects are reference counted objects. This means that their
1662 last reference count put is not predictable, and the kobject can
1663 live on past the point at which a driver decides to drop its
1664 initial reference to the kobject gained on allocation. An
1665 example of this would be a struct device which has just been
1668 However, some buggy drivers assume that after such an operation,
1669 the memory backing the kobject can be immediately freed. This
1670 goes completely against the principles of a refcounted object.
1672 If you say Y here, the kernel will delay the release of kobjects
1673 on the last reference count to improve the visibility of this
1674 kind of kobject release bug.
1676 config HAVE_DEBUG_BUGVERBOSE
1679 menu "Debug kernel data structures"
1682 bool "Debug linked list manipulation"
1683 depends on DEBUG_KERNEL
1684 select LIST_HARDENED
1686 Enable this to turn on extended checks in the linked-list walking
1689 This option trades better quality error reports for performance, and
1690 is more suitable for kernel debugging. If you care about performance,
1691 you should only enable CONFIG_LIST_HARDENED instead.
1696 bool "Debug priority linked list manipulation"
1697 depends on DEBUG_KERNEL
1699 Enable this to turn on extended checks in the priority-ordered
1700 linked-list (plist) walking routines. This checks the entire
1701 list multiple times during each manipulation.
1706 bool "Debug SG table operations"
1707 depends on DEBUG_KERNEL
1709 Enable this to turn on checks on scatter-gather tables. This can
1710 help find problems with drivers that do not properly initialize
1715 config DEBUG_NOTIFIERS
1716 bool "Debug notifier call chains"
1717 depends on DEBUG_KERNEL
1719 Enable this to turn on sanity checking for notifier call chains.
1720 This is most useful for kernel developers to make sure that
1721 modules properly unregister themselves from notifier chains.
1722 This is a relatively cheap check but if you care about maximum
1725 config DEBUG_CLOSURES
1726 bool "Debug closures (bcache async widgits)"
1730 Keeps all active closures in a linked list and provides a debugfs
1731 interface to list them, which makes it possible to see asynchronous
1732 operations that get stuck.
1734 config DEBUG_MAPLE_TREE
1735 bool "Debug maple trees"
1736 depends on DEBUG_KERNEL
1738 Enable maple tree debugging information and extra validations.
1744 source "kernel/rcu/Kconfig.debug"
1746 config DEBUG_WQ_FORCE_RR_CPU
1747 bool "Force round-robin CPU selection for unbound work items"
1748 depends on DEBUG_KERNEL
1751 Workqueue used to implicitly guarantee that work items queued
1752 without explicit CPU specified are put on the local CPU. This
1753 guarantee is no longer true and while local CPU is still
1754 preferred work items may be put on foreign CPUs. Kernel
1755 parameter "workqueue.debug_force_rr_cpu" is added to force
1756 round-robin CPU selection to flush out usages which depend on the
1757 now broken guarantee. This config option enables the debug
1758 feature by default. When enabled, memory and cache locality will
1761 config CPU_HOTPLUG_STATE_CONTROL
1762 bool "Enable CPU hotplug state control"
1763 depends on DEBUG_KERNEL
1764 depends on HOTPLUG_CPU
1767 Allows to write steps between "offline" and "online" to the CPUs
1768 sysfs target file so states can be stepped granular. This is a debug
1769 option for now as the hotplug machinery cannot be stopped and
1770 restarted at arbitrary points yet.
1772 Say N if your are unsure.
1775 bool "Latency measuring infrastructure"
1776 depends on DEBUG_KERNEL
1777 depends on STACKTRACE_SUPPORT
1779 depends on FRAME_POINTER || MIPS || PPC || S390 || MICROBLAZE || ARM || ARC || X86
1785 Enable this option if you want to use the LatencyTOP tool
1786 to find out which userspace is blocking on what kernel operations.
1788 config DEBUG_CGROUP_REF
1789 bool "Disable inlining of cgroup css reference count functions"
1790 depends on DEBUG_KERNEL
1795 Force cgroup css reference count functions to not be inlined so
1796 that they can be kprobed for debugging.
1798 source "kernel/trace/Kconfig"
1800 config PROVIDE_OHCI1394_DMA_INIT
1801 bool "Remote debugging over FireWire early on boot"
1802 depends on PCI && X86
1804 If you want to debug problems which hang or crash the kernel early
1805 on boot and the crashing machine has a FireWire port, you can use
1806 this feature to remotely access the memory of the crashed machine
1807 over FireWire. This employs remote DMA as part of the OHCI1394
1808 specification which is now the standard for FireWire controllers.
1810 With remote DMA, you can monitor the printk buffer remotely using
1811 firescope and access all memory below 4GB using fireproxy from gdb.
1812 Even controlling a kernel debugger is possible using remote DMA.
1816 If ohci1394_dma=early is used as boot parameter, it will initialize
1817 all OHCI1394 controllers which are found in the PCI config space.
1819 As all changes to the FireWire bus such as enabling and disabling
1820 devices cause a bus reset and thereby disable remote DMA for all
1821 devices, be sure to have the cable plugged and FireWire enabled on
1822 the debugging host before booting the debug target for debugging.
1824 This code (~1k) is freed after boot. By then, the firewire stack
1825 in charge of the OHCI-1394 controllers should be used instead.
1827 See Documentation/core-api/debugging-via-ohci1394.rst for more information.
1829 source "samples/Kconfig"
1831 config ARCH_HAS_DEVMEM_IS_ALLOWED
1834 config STRICT_DEVMEM
1835 bool "Filter access to /dev/mem"
1836 depends on MMU && DEVMEM
1837 depends on ARCH_HAS_DEVMEM_IS_ALLOWED || GENERIC_LIB_DEVMEM_IS_ALLOWED
1838 default y if PPC || X86 || ARM64
1840 If this option is disabled, you allow userspace (root) access to all
1841 of memory, including kernel and userspace memory. Accidental
1842 access to this is obviously disastrous, but specific access can
1843 be used by people debugging the kernel. Note that with PAT support
1844 enabled, even in this case there are restrictions on /dev/mem
1845 use due to the cache aliasing requirements.
1847 If this option is switched on, and IO_STRICT_DEVMEM=n, the /dev/mem
1848 file only allows userspace access to PCI space and the BIOS code and
1849 data regions. This is sufficient for dosemu and X and all common
1854 config IO_STRICT_DEVMEM
1855 bool "Filter I/O access to /dev/mem"
1856 depends on STRICT_DEVMEM
1858 If this option is disabled, you allow userspace (root) access to all
1859 io-memory regardless of whether a driver is actively using that
1860 range. Accidental access to this is obviously disastrous, but
1861 specific access can be used by people debugging kernel drivers.
1863 If this option is switched on, the /dev/mem file only allows
1864 userspace access to *idle* io-memory ranges (see /proc/iomem) This
1865 may break traditional users of /dev/mem (dosemu, legacy X, etc...)
1866 if the driver using a given range cannot be disabled.
1870 menu "$(SRCARCH) Debugging"
1872 source "arch/$(SRCARCH)/Kconfig.debug"
1876 menu "Kernel Testing and Coverage"
1878 source "lib/kunit/Kconfig"
1880 config NOTIFIER_ERROR_INJECTION
1881 tristate "Notifier error injection"
1882 depends on DEBUG_KERNEL
1885 This option provides the ability to inject artificial errors to
1886 specified notifier chain callbacks. It is useful to test the error
1887 handling of notifier call chain failures.
1891 config PM_NOTIFIER_ERROR_INJECT
1892 tristate "PM notifier error injection module"
1893 depends on PM && NOTIFIER_ERROR_INJECTION
1894 default m if PM_DEBUG
1896 This option provides the ability to inject artificial errors to
1897 PM notifier chain callbacks. It is controlled through debugfs
1898 interface /sys/kernel/debug/notifier-error-inject/pm
1900 If the notifier call chain should be failed with some events
1901 notified, write the error code to "actions/<notifier event>/error".
1903 Example: Inject PM suspend error (-12 = -ENOMEM)
1905 # cd /sys/kernel/debug/notifier-error-inject/pm/
1906 # echo -12 > actions/PM_SUSPEND_PREPARE/error
1907 # echo mem > /sys/power/state
1908 bash: echo: write error: Cannot allocate memory
1910 To compile this code as a module, choose M here: the module will
1911 be called pm-notifier-error-inject.
1915 config OF_RECONFIG_NOTIFIER_ERROR_INJECT
1916 tristate "OF reconfig notifier error injection module"
1917 depends on OF_DYNAMIC && NOTIFIER_ERROR_INJECTION
1919 This option provides the ability to inject artificial errors to
1920 OF reconfig notifier chain callbacks. It is controlled
1921 through debugfs interface under
1922 /sys/kernel/debug/notifier-error-inject/OF-reconfig/
1924 If the notifier call chain should be failed with some events
1925 notified, write the error code to "actions/<notifier event>/error".
1927 To compile this code as a module, choose M here: the module will
1928 be called of-reconfig-notifier-error-inject.
1932 config NETDEV_NOTIFIER_ERROR_INJECT
1933 tristate "Netdev notifier error injection module"
1934 depends on NET && NOTIFIER_ERROR_INJECTION
1936 This option provides the ability to inject artificial errors to
1937 netdevice notifier chain callbacks. It is controlled through debugfs
1938 interface /sys/kernel/debug/notifier-error-inject/netdev
1940 If the notifier call chain should be failed with some events
1941 notified, write the error code to "actions/<notifier event>/error".
1943 Example: Inject netdevice mtu change error (-22 = -EINVAL)
1945 # cd /sys/kernel/debug/notifier-error-inject/netdev
1946 # echo -22 > actions/NETDEV_CHANGEMTU/error
1947 # ip link set eth0 mtu 1024
1948 RTNETLINK answers: Invalid argument
1950 To compile this code as a module, choose M here: the module will
1951 be called netdev-notifier-error-inject.
1955 config FUNCTION_ERROR_INJECTION
1956 bool "Fault-injections of functions"
1957 depends on HAVE_FUNCTION_ERROR_INJECTION && KPROBES
1959 Add fault injections into various functions that are annotated with
1960 ALLOW_ERROR_INJECTION() in the kernel. BPF may also modify the return
1961 value of these functions. This is useful to test error paths of code.
1965 config FAULT_INJECTION
1966 bool "Fault-injection framework"
1967 depends on DEBUG_KERNEL
1969 Provide fault-injection framework.
1970 For more details, see Documentation/fault-injection/.
1973 bool "Fault-injection capability for kmalloc"
1974 depends on FAULT_INJECTION
1976 Provide fault-injection capability for kmalloc.
1978 config FAIL_PAGE_ALLOC
1979 bool "Fault-injection capability for alloc_pages()"
1980 depends on FAULT_INJECTION
1982 Provide fault-injection capability for alloc_pages().
1984 config FAULT_INJECTION_USERCOPY
1985 bool "Fault injection capability for usercopy functions"
1986 depends on FAULT_INJECTION
1988 Provides fault-injection capability to inject failures
1989 in usercopy functions (copy_from_user(), get_user(), ...).
1991 config FAIL_MAKE_REQUEST
1992 bool "Fault-injection capability for disk IO"
1993 depends on FAULT_INJECTION && BLOCK
1995 Provide fault-injection capability for disk IO.
1997 config FAIL_IO_TIMEOUT
1998 bool "Fault-injection capability for faking disk interrupts"
1999 depends on FAULT_INJECTION && BLOCK
2001 Provide fault-injection capability on end IO handling. This
2002 will make the block layer "forget" an interrupt as configured,
2003 thus exercising the error handling.
2005 Only works with drivers that use the generic timeout handling,
2006 for others it won't do anything.
2009 bool "Fault-injection capability for futexes"
2011 depends on FAULT_INJECTION && FUTEX
2013 Provide fault-injection capability for futexes.
2015 config FAULT_INJECTION_DEBUG_FS
2016 bool "Debugfs entries for fault-injection capabilities"
2017 depends on FAULT_INJECTION && SYSFS && DEBUG_FS
2019 Enable configuration of fault-injection capabilities via debugfs.
2021 config FAIL_FUNCTION
2022 bool "Fault-injection capability for functions"
2023 depends on FAULT_INJECTION_DEBUG_FS && FUNCTION_ERROR_INJECTION
2025 Provide function-based fault-injection capability.
2026 This will allow you to override a specific function with a return
2027 with given return value. As a result, function caller will see
2028 an error value and have to handle it. This is useful to test the
2029 error handling in various subsystems.
2031 config FAIL_MMC_REQUEST
2032 bool "Fault-injection capability for MMC IO"
2033 depends on FAULT_INJECTION_DEBUG_FS && MMC
2035 Provide fault-injection capability for MMC IO.
2036 This will make the mmc core return data errors. This is
2037 useful to test the error handling in the mmc block device
2038 and to test how the mmc host driver handles retries from
2042 bool "Fault-injection capability for SunRPC"
2043 depends on FAULT_INJECTION_DEBUG_FS && SUNRPC_DEBUG
2045 Provide fault-injection capability for SunRPC and
2048 config FAULT_INJECTION_CONFIGFS
2049 bool "Configfs interface for fault-injection capabilities"
2050 depends on FAULT_INJECTION
2053 This option allows configfs-based drivers to dynamically configure
2054 fault-injection via configfs. Each parameter for driver-specific
2055 fault-injection can be made visible as a configfs attribute in a
2059 config FAULT_INJECTION_STACKTRACE_FILTER
2060 bool "stacktrace filter for fault-injection capabilities"
2061 depends on FAULT_INJECTION
2062 depends on (FAULT_INJECTION_DEBUG_FS || FAULT_INJECTION_CONFIGFS) && STACKTRACE_SUPPORT
2064 depends on FRAME_POINTER || MIPS || PPC || S390 || MICROBLAZE || ARM || ARC || X86
2066 Provide stacktrace filter for fault-injection capabilities
2068 config ARCH_HAS_KCOV
2071 An architecture should select this when it can successfully
2072 build and run with CONFIG_KCOV. This typically requires
2073 disabling instrumentation for some early boot code.
2075 config CC_HAS_SANCOV_TRACE_PC
2076 def_bool $(cc-option,-fsanitize-coverage=trace-pc)
2080 bool "Code coverage for fuzzing"
2081 depends on ARCH_HAS_KCOV
2082 depends on CC_HAS_SANCOV_TRACE_PC || GCC_PLUGINS
2083 depends on !ARCH_WANTS_NO_INSTR || HAVE_NOINSTR_HACK || \
2084 GCC_VERSION >= 120000 || CLANG_VERSION >= 130000
2086 select GCC_PLUGIN_SANCOV if !CC_HAS_SANCOV_TRACE_PC
2087 select OBJTOOL if HAVE_NOINSTR_HACK
2089 KCOV exposes kernel code coverage information in a form suitable
2090 for coverage-guided fuzzing (randomized testing).
2092 For more details, see Documentation/dev-tools/kcov.rst.
2094 config KCOV_ENABLE_COMPARISONS
2095 bool "Enable comparison operands collection by KCOV"
2097 depends on $(cc-option,-fsanitize-coverage=trace-cmp)
2099 KCOV also exposes operands of every comparison in the instrumented
2100 code along with operand sizes and PCs of the comparison instructions.
2101 These operands can be used by fuzzing engines to improve the quality
2102 of fuzzing coverage.
2104 config KCOV_INSTRUMENT_ALL
2105 bool "Instrument all code by default"
2109 If you are doing generic system call fuzzing (like e.g. syzkaller),
2110 then you will want to instrument the whole kernel and you should
2111 say y here. If you are doing more targeted fuzzing (like e.g.
2112 filesystem fuzzing with AFL) then you will want to enable coverage
2113 for more specific subsets of files, and should say n here.
2115 config KCOV_IRQ_AREA_SIZE
2116 hex "Size of interrupt coverage collection area in words"
2120 KCOV uses preallocated per-cpu areas to collect coverage from
2121 soft interrupts. This specifies the size of those areas in the
2122 number of unsigned long words.
2124 menuconfig RUNTIME_TESTING_MENU
2125 bool "Runtime Testing"
2128 if RUNTIME_TESTING_MENU
2131 tristate "Dhrystone benchmark test"
2133 Enable this to include the Dhrystone 2.1 benchmark. This test
2134 calculates the number of Dhrystones per second, and the number of
2135 DMIPS (Dhrystone MIPS) obtained when the Dhrystone score is divided
2136 by 1757 (the number of Dhrystones per second obtained on the VAX
2137 11/780, nominally a 1 MIPS machine).
2139 To run the benchmark, it needs to be enabled explicitly, either from
2140 the kernel command line (when built-in), or from userspace (when
2141 built-in or modular.
2143 Run once during kernel boot:
2147 Set number of iterations from kernel command line:
2149 test_dhry.iterations=<n>
2151 Set number of iterations from userspace:
2153 echo <n> > /sys/module/test_dhry/parameters/iterations
2155 Trigger manual run from userspace:
2157 echo y > /sys/module/test_dhry/parameters/run
2159 If the number of iterations is <= 0, the test will devise a suitable
2160 number of iterations (test runs for at least 2s) automatically.
2161 This process takes ca. 4s.
2166 tristate "Linux Kernel Dump Test Tool Module"
2169 This module enables testing of the different dumping mechanisms by
2170 inducing system failures at predefined crash points.
2171 If you don't need it: say N
2172 Choose M here to compile this code as a module. The module will be
2175 Documentation on how to use the module can be found in
2176 Documentation/fault-injection/provoke-crashes.rst
2178 config CPUMASK_KUNIT_TEST
2179 tristate "KUnit test for cpumask" if !KUNIT_ALL_TESTS
2181 default KUNIT_ALL_TESTS
2183 Enable to turn on cpumask tests, running at boot or module load time.
2185 For more information on KUnit and unit tests in general, please refer
2186 to the KUnit documentation in Documentation/dev-tools/kunit/.
2190 config TEST_LIST_SORT
2191 tristate "Linked list sorting test" if !KUNIT_ALL_TESTS
2193 default KUNIT_ALL_TESTS
2195 Enable this to turn on 'list_sort()' function test. This test is
2196 executed only once during system boot (so affects only boot time),
2197 or at module load time.
2201 config TEST_MIN_HEAP
2202 tristate "Min heap test"
2203 depends on DEBUG_KERNEL || m
2205 Enable this to turn on min heap function tests. This test is
2206 executed only once during system boot (so affects only boot time),
2207 or at module load time.
2212 tristate "Array-based sort test" if !KUNIT_ALL_TESTS
2214 default KUNIT_ALL_TESTS
2216 This option enables the self-test function of 'sort()' at boot,
2217 or at module load time.
2222 tristate "64bit/32bit division and modulo test"
2223 depends on DEBUG_KERNEL || m
2225 Enable this to turn on 'do_div()' function test. This test is
2226 executed only once during system boot (so affects only boot time),
2227 or at module load time.
2231 config TEST_IOV_ITER
2232 tristate "Test iov_iter operation" if !KUNIT_ALL_TESTS
2234 default KUNIT_ALL_TESTS
2236 Enable this to turn on testing of the operation of the I/O iterator
2237 (iov_iter). This test is executed only once during system boot (so
2238 affects only boot time), or at module load time.
2242 config KPROBES_SANITY_TEST
2243 tristate "Kprobes sanity tests" if !KUNIT_ALL_TESTS
2244 depends on DEBUG_KERNEL
2247 select STACKTRACE if ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
2248 default KUNIT_ALL_TESTS
2250 This option provides for testing basic kprobes functionality on
2251 boot. Samples of kprobe and kretprobe are inserted and
2252 verified for functionality.
2254 Say N if you are unsure.
2256 config FPROBE_SANITY_TEST
2257 bool "Self test for fprobe"
2258 depends on DEBUG_KERNEL
2262 This option will enable testing the fprobe when the system boot.
2263 A series of tests are made to verify that the fprobe is functioning
2266 Say N if you are unsure.
2268 config BACKTRACE_SELF_TEST
2269 tristate "Self test for the backtrace code"
2270 depends on DEBUG_KERNEL
2272 This option provides a kernel module that can be used to test
2273 the kernel stack backtrace code. This option is not useful
2274 for distributions or general kernels, but only for kernel
2275 developers working on architecture code.
2277 Note that if you want to also test saved backtraces, you will
2278 have to enable STACKTRACE as well.
2280 Say N if you are unsure.
2282 config TEST_REF_TRACKER
2283 tristate "Self test for reference tracker"
2284 depends on DEBUG_KERNEL && STACKTRACE_SUPPORT
2287 This option provides a kernel module performing tests
2288 using reference tracker infrastructure.
2290 Say N if you are unsure.
2293 tristate "Red-Black tree test"
2294 depends on DEBUG_KERNEL
2296 A benchmark measuring the performance of the rbtree library.
2297 Also includes rbtree invariant checks.
2299 config REED_SOLOMON_TEST
2300 tristate "Reed-Solomon library test"
2301 depends on DEBUG_KERNEL || m
2303 select REED_SOLOMON_ENC16
2304 select REED_SOLOMON_DEC16
2306 This option enables the self-test function of rslib at boot,
2307 or at module load time.
2311 config INTERVAL_TREE_TEST
2312 tristate "Interval tree test"
2313 depends on DEBUG_KERNEL
2314 select INTERVAL_TREE
2316 A benchmark measuring the performance of the interval tree library
2319 tristate "Per cpu operations test"
2320 depends on m && DEBUG_KERNEL
2322 Enable this option to build test module which validates per-cpu
2327 config ATOMIC64_SELFTEST
2328 tristate "Perform an atomic64_t self-test"
2330 Enable this option to test the atomic64_t functions at boot or
2331 at module load time.
2335 config ASYNC_RAID6_TEST
2336 tristate "Self test for hardware accelerated raid6 recovery"
2337 depends on ASYNC_RAID6_RECOV
2340 This is a one-shot self test that permutes through the
2341 recovery of all the possible two disk failure scenarios for a
2342 N-disk array. Recovery is performed with the asynchronous
2343 raid6 recovery routines, and will optionally use an offload
2344 engine if one is available.
2349 tristate "Test functions located in the hexdump module at runtime"
2351 config STRING_SELFTEST
2352 tristate "Test string functions at runtime"
2354 config TEST_STRING_HELPERS
2355 tristate "Test functions located in the string_helpers module at runtime"
2358 tristate "Test kstrto*() family of functions at runtime"
2361 tristate "Test printf() family of functions at runtime"
2364 tristate "Test scanf() family of functions at runtime"
2367 tristate "Test bitmap_*() family of functions at runtime"
2369 Enable this option to test the bitmap functions at boot.
2374 tristate "Test functions located in the uuid module at runtime"
2377 tristate "Test the XArray code at runtime"
2379 config TEST_MAPLE_TREE
2380 tristate "Test the Maple Tree code at runtime or module load"
2382 Enable this option to test the maple tree code functions at boot, or
2383 when the module is loaded. Enable "Debug Maple Trees" will enable
2384 more verbose output on failures.
2388 config TEST_RHASHTABLE
2389 tristate "Perform selftest on resizable hash table"
2391 Enable this option to test the rhashtable functions at boot.
2396 tristate "Perform selftest on IDA functions"
2399 tristate "Perform selftest on priority array manager"
2402 Enable this option to test priority array manager on boot
2407 config TEST_IRQ_TIMINGS
2408 bool "IRQ timings selftest"
2409 depends on IRQ_TIMINGS
2411 Enable this option to test the irq timings code on boot.
2416 tristate "Test module loading with 'hello world' module"
2419 This builds the "test_module" module that emits "Hello, world"
2420 on printk when loaded. It is designed to be used for basic
2421 evaluation of the module loading subsystem (for example when
2422 validating module verification). It lacks any extra dependencies,
2423 and will not normally be loaded by the system unless explicitly
2429 tristate "Test module for compilation of bitops operations"
2432 This builds the "test_bitops" module that is much like the
2433 TEST_LKM module except that it does a basic exercise of the
2434 set/clear_bit macros and get_count_order/long to make sure there are
2435 no compiler warnings from C=1 sparse checker or -Wextra
2436 compilations. It has no dependencies and doesn't run or load unless
2437 explicitly requested by name. for example: modprobe test_bitops.
2442 tristate "Test module for stress/performance analysis of vmalloc allocator"
2447 This builds the "test_vmalloc" module that should be used for
2448 stress and performance analysis. So, any new change for vmalloc
2449 subsystem can be evaluated from performance and stability point
2454 config TEST_USER_COPY
2455 tristate "Test user/kernel boundary protections"
2458 This builds the "test_user_copy" module that runs sanity checks
2459 on the copy_to/from_user infrastructure, making sure basic
2460 user/kernel boundary testing is working. If it fails to load,
2461 a regression has been detected in the user/kernel memory boundary
2467 tristate "Test BPF filter functionality"
2470 This builds the "test_bpf" module that runs various test vectors
2471 against the BPF interpreter or BPF JIT compiler depending on the
2472 current setting. This is in particular useful for BPF JIT compiler
2473 development, but also to run regression tests against changes in
2474 the interpreter code. It also enables test stubs for eBPF maps and
2475 verifier used by user space verifier testsuite.
2479 config TEST_BLACKHOLE_DEV
2480 tristate "Test blackhole netdev functionality"
2483 This builds the "test_blackhole_dev" module that validates the
2484 data path through this blackhole netdev.
2488 config FIND_BIT_BENCHMARK
2489 tristate "Test find_bit functions"
2491 This builds the "test_find_bit" module that measure find_*_bit()
2492 functions performance.
2496 config TEST_FIRMWARE
2497 tristate "Test firmware loading via userspace interface"
2498 depends on FW_LOADER
2500 This builds the "test_firmware" module that creates a userspace
2501 interface for testing firmware loading. This can be used to
2502 control the triggering of firmware loading without needing an
2503 actual firmware-using device. The contents can be rechecked by
2509 tristate "sysctl test driver"
2510 depends on PROC_SYSCTL
2512 This builds the "test_sysctl" module. This driver enables to test the
2513 proc sysctl interfaces available to drivers safely without affecting
2514 production knobs which might alter system functionality.
2518 config BITFIELD_KUNIT
2519 tristate "KUnit test bitfield functions at runtime" if !KUNIT_ALL_TESTS
2521 default KUNIT_ALL_TESTS
2523 Enable this option to test the bitfield functions at boot.
2525 KUnit tests run during boot and output the results to the debug log
2526 in TAP format (http://testanything.org/). Only useful for kernel devs
2527 running the KUnit test harness, and not intended for inclusion into a
2530 For more information on KUnit and unit tests in general please refer
2531 to the KUnit documentation in Documentation/dev-tools/kunit/.
2535 config CHECKSUM_KUNIT
2536 tristate "KUnit test checksum functions at runtime" if !KUNIT_ALL_TESTS
2538 default KUNIT_ALL_TESTS
2540 Enable this option to test the checksum functions at boot.
2542 KUnit tests run during boot and output the results to the debug log
2543 in TAP format (http://testanything.org/). Only useful for kernel devs
2544 running the KUnit test harness, and not intended for inclusion into a
2547 For more information on KUnit and unit tests in general please refer
2548 to the KUnit documentation in Documentation/dev-tools/kunit/.
2552 config HASH_KUNIT_TEST
2553 tristate "KUnit Test for integer hash functions" if !KUNIT_ALL_TESTS
2555 default KUNIT_ALL_TESTS
2557 Enable this option to test the kernel's string (<linux/stringhash.h>), and
2558 integer (<linux/hash.h>) hash functions on boot.
2560 KUnit tests run during boot and output the results to the debug log
2561 in TAP format (https://testanything.org/). Only useful for kernel devs
2562 running the KUnit test harness, and not intended for inclusion into a
2565 For more information on KUnit and unit tests in general please refer
2566 to the KUnit documentation in Documentation/dev-tools/kunit/.
2568 This is intended to help people writing architecture-specific
2569 optimized versions. If unsure, say N.
2571 config RESOURCE_KUNIT_TEST
2572 tristate "KUnit test for resource API" if !KUNIT_ALL_TESTS
2574 default KUNIT_ALL_TESTS
2576 This builds the resource API unit test.
2577 Tests the logic of API provided by resource.c and ioport.h.
2578 For more information on KUnit and unit tests in general please refer
2579 to the KUnit documentation in Documentation/dev-tools/kunit/.
2583 config SYSCTL_KUNIT_TEST
2584 tristate "KUnit test for sysctl" if !KUNIT_ALL_TESTS
2586 default KUNIT_ALL_TESTS
2588 This builds the proc sysctl unit test, which runs on boot.
2589 Tests the API contract and implementation correctness of sysctl.
2590 For more information on KUnit and unit tests in general please refer
2591 to the KUnit documentation in Documentation/dev-tools/kunit/.
2595 config LIST_KUNIT_TEST
2596 tristate "KUnit Test for Kernel Linked-list structures" if !KUNIT_ALL_TESTS
2598 default KUNIT_ALL_TESTS
2600 This builds the linked list KUnit test suite.
2601 It tests that the API and basic functionality of the list_head type
2602 and associated macros.
2604 KUnit tests run during boot and output the results to the debug log
2605 in TAP format (https://testanything.org/). Only useful for kernel devs
2606 running the KUnit test harness, and not intended for inclusion into a
2609 For more information on KUnit and unit tests in general please refer
2610 to the KUnit documentation in Documentation/dev-tools/kunit/.
2614 config HASHTABLE_KUNIT_TEST
2615 tristate "KUnit Test for Kernel Hashtable structures" if !KUNIT_ALL_TESTS
2617 default KUNIT_ALL_TESTS
2619 This builds the hashtable KUnit test suite.
2620 It tests the basic functionality of the API defined in
2621 include/linux/hashtable.h. For more information on KUnit and
2622 unit tests in general please refer to the KUnit documentation
2623 in Documentation/dev-tools/kunit/.
2627 config LINEAR_RANGES_TEST
2628 tristate "KUnit test for linear_ranges"
2630 select LINEAR_RANGES
2632 This builds the linear_ranges unit test, which runs on boot.
2633 Tests the linear_ranges logic correctness.
2634 For more information on KUnit and unit tests in general please refer
2635 to the KUnit documentation in Documentation/dev-tools/kunit/.
2639 config CMDLINE_KUNIT_TEST
2640 tristate "KUnit test for cmdline API" if !KUNIT_ALL_TESTS
2642 default KUNIT_ALL_TESTS
2644 This builds the cmdline API unit test.
2645 Tests the logic of API provided by cmdline.c.
2646 For more information on KUnit and unit tests in general please refer
2647 to the KUnit documentation in Documentation/dev-tools/kunit/.
2652 tristate "KUnit test for bits.h" if !KUNIT_ALL_TESTS
2654 default KUNIT_ALL_TESTS
2656 This builds the bits unit test.
2657 Tests the logic of macros defined in bits.h.
2658 For more information on KUnit and unit tests in general please refer
2659 to the KUnit documentation in Documentation/dev-tools/kunit/.
2663 config SLUB_KUNIT_TEST
2664 tristate "KUnit test for SLUB cache error detection" if !KUNIT_ALL_TESTS
2665 depends on SLUB_DEBUG && KUNIT
2666 default KUNIT_ALL_TESTS
2668 This builds SLUB allocator unit test.
2669 Tests SLUB cache debugging functionality.
2670 For more information on KUnit and unit tests in general please refer
2671 to the KUnit documentation in Documentation/dev-tools/kunit/.
2675 config RATIONAL_KUNIT_TEST
2676 tristate "KUnit test for rational.c" if !KUNIT_ALL_TESTS
2677 depends on KUNIT && RATIONAL
2678 default KUNIT_ALL_TESTS
2680 This builds the rational math unit test.
2681 For more information on KUnit and unit tests in general please refer
2682 to the KUnit documentation in Documentation/dev-tools/kunit/.
2686 config MEMCPY_KUNIT_TEST
2687 tristate "Test memcpy(), memmove(), and memset() functions at runtime" if !KUNIT_ALL_TESTS
2689 default KUNIT_ALL_TESTS
2691 Builds unit tests for memcpy(), memmove(), and memset() functions.
2692 For more information on KUnit and unit tests in general please refer
2693 to the KUnit documentation in Documentation/dev-tools/kunit/.
2697 config MEMCPY_SLOW_KUNIT_TEST
2698 bool "Include exhaustive memcpy tests"
2699 depends on MEMCPY_KUNIT_TEST
2702 Some memcpy tests are quite exhaustive in checking for overlaps
2703 and bit ranges. These can be very slow, so they are split out
2704 as a separate config, in case they need to be disabled.
2706 Note this config option will be replaced by the use of KUnit test
2709 config IS_SIGNED_TYPE_KUNIT_TEST
2710 tristate "Test is_signed_type() macro" if !KUNIT_ALL_TESTS
2712 default KUNIT_ALL_TESTS
2714 Builds unit tests for the is_signed_type() macro.
2716 For more information on KUnit and unit tests in general please refer
2717 to the KUnit documentation in Documentation/dev-tools/kunit/.
2721 config OVERFLOW_KUNIT_TEST
2722 tristate "Test check_*_overflow() functions at runtime" if !KUNIT_ALL_TESTS
2724 default KUNIT_ALL_TESTS
2726 Builds unit tests for the check_*_overflow(), size_*(), allocation, and
2729 For more information on KUnit and unit tests in general please refer
2730 to the KUnit documentation in Documentation/dev-tools/kunit/.
2734 config STACKINIT_KUNIT_TEST
2735 tristate "Test level of stack variable initialization" if !KUNIT_ALL_TESTS
2737 default KUNIT_ALL_TESTS
2739 Test if the kernel is zero-initializing stack variables and
2740 padding. Coverage is controlled by compiler flags,
2741 CONFIG_INIT_STACK_ALL_PATTERN, CONFIG_INIT_STACK_ALL_ZERO,
2742 CONFIG_GCC_PLUGIN_STRUCTLEAK, CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF,
2743 or CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL.
2745 config FORTIFY_KUNIT_TEST
2746 tristate "Test fortified str*() and mem*() function internals at runtime" if !KUNIT_ALL_TESTS
2747 depends on KUNIT && FORTIFY_SOURCE
2748 default KUNIT_ALL_TESTS
2750 Builds unit tests for checking internals of FORTIFY_SOURCE as used
2751 by the str*() and mem*() family of functions. For testing runtime
2752 traps of FORTIFY_SOURCE, see LKDTM's "FORTIFY_*" tests.
2754 config HW_BREAKPOINT_KUNIT_TEST
2755 bool "Test hw_breakpoint constraints accounting" if !KUNIT_ALL_TESTS
2756 depends on HAVE_HW_BREAKPOINT
2758 default KUNIT_ALL_TESTS
2760 Tests for hw_breakpoint constraints accounting.
2764 config STRCAT_KUNIT_TEST
2765 tristate "Test strcat() family of functions at runtime" if !KUNIT_ALL_TESTS
2767 default KUNIT_ALL_TESTS
2769 config STRSCPY_KUNIT_TEST
2770 tristate "Test strscpy*() family of functions at runtime" if !KUNIT_ALL_TESTS
2772 default KUNIT_ALL_TESTS
2774 config SIPHASH_KUNIT_TEST
2775 tristate "Perform selftest on siphash functions" if !KUNIT_ALL_TESTS
2777 default KUNIT_ALL_TESTS
2779 Enable this option to test the kernel's siphash (<linux/siphash.h>) hash
2780 functions on boot (or module load).
2782 This is intended to help people writing architecture-specific
2783 optimized versions. If unsure, say N.
2786 tristate "udelay test driver"
2788 This builds the "udelay_test" module that helps to make sure
2789 that udelay() is working properly.
2793 config TEST_STATIC_KEYS
2794 tristate "Test static keys"
2797 Test the static key interfaces.
2801 config TEST_DYNAMIC_DEBUG
2802 tristate "Test DYNAMIC_DEBUG"
2803 depends on DYNAMIC_DEBUG
2805 This module registers a tracer callback to count enabled
2806 pr_debugs in a 'do_debugging' function, then alters their
2807 enablements, calls the function, and compares counts.
2812 tristate "kmod stress tester"
2814 depends on NETDEVICES && NET_CORE && INET # for TUN
2816 depends on PAGE_SIZE_LESS_THAN_256KB # for BTRFS
2822 Test the kernel's module loading mechanism: kmod. kmod implements
2823 support to load modules using the Linux kernel's usermode helper.
2824 This test provides a series of tests against kmod.
2826 Although technically you can either build test_kmod as a module or
2827 into the kernel we disallow building it into the kernel since
2828 it stress tests request_module() and this will very likely cause
2829 some issues by taking over precious threads available from other
2830 module load requests, ultimately this could be fatal.
2834 tools/testing/selftests/kmod/kmod.sh --help
2838 config TEST_DEBUG_VIRTUAL
2839 tristate "Test CONFIG_DEBUG_VIRTUAL feature"
2840 depends on DEBUG_VIRTUAL
2842 Test the kernel's ability to detect incorrect calls to
2843 virt_to_phys() done against the non-linear part of the
2844 kernel's virtual address map.
2848 config TEST_MEMCAT_P
2849 tristate "Test memcat_p() helper function"
2851 Test the memcat_p() helper for correctly merging two
2852 pointer arrays together.
2856 config TEST_LIVEPATCH
2857 tristate "Test livepatching"
2859 depends on DYNAMIC_DEBUG
2860 depends on LIVEPATCH
2863 Test kernel livepatching features for correctness. The tests will
2864 load test modules that will be livepatched in various scenarios.
2866 To run all the livepatching tests:
2868 make -C tools/testing/selftests TARGETS=livepatch run_tests
2870 Alternatively, individual tests may be invoked:
2872 tools/testing/selftests/livepatch/test-callbacks.sh
2873 tools/testing/selftests/livepatch/test-livepatch.sh
2874 tools/testing/selftests/livepatch/test-shadow-vars.sh
2879 tristate "Perform selftest on object aggreration manager"
2883 Enable this option to test object aggregation manager on boot
2887 tristate "Test heap/page initialization"
2889 Test if the kernel is zero-initializing heap and page allocations.
2890 This can be useful to test init_on_alloc and init_on_free features.
2895 tristate "Test HMM (Heterogeneous Memory Management)"
2896 depends on TRANSPARENT_HUGEPAGE
2897 depends on DEVICE_PRIVATE
2901 This is a pseudo device driver solely for testing HMM.
2902 Say M here if you want to build the HMM test module.
2903 Doing so will allow you to run tools/testing/selftest/vm/hmm-tests.
2907 config TEST_FREE_PAGES
2908 tristate "Test freeing pages"
2910 Test that a memory leak does not occur due to a race between
2911 freeing a block of pages and a speculative page reference.
2912 Loading this module is safe if your kernel has the bug fixed.
2913 If the bug is not fixed, it will leak gigabytes of memory and
2914 probably OOM your system.
2917 tristate "Test floating point operations in kernel space"
2918 depends on X86 && !KCOV_INSTRUMENT_ALL
2920 Enable this option to add /sys/kernel/debug/selftest_helpers/test_fpu
2921 which will trigger a sequence of floating point operations. This is used
2922 for self-testing floating point control register setting in
2927 config TEST_CLOCKSOURCE_WATCHDOG
2928 tristate "Test clocksource watchdog in kernel space"
2929 depends on CLOCKSOURCE_WATCHDOG
2931 Enable this option to create a kernel module that will trigger
2932 a test of the clocksource watchdog. This module may be loaded
2933 via modprobe or insmod in which case it will run upon being
2934 loaded, or it may be built in, in which case it will run
2940 tristate "Test module for correctness and stress of objpool"
2942 depends on m && DEBUG_KERNEL
2944 This builds the "test_objpool" module that should be used for
2945 correctness verification and concurrent testings of objects
2946 allocation and reclamation.
2950 endif # RUNTIME_TESTING_MENU
2952 config ARCH_USE_MEMTEST
2955 An architecture should select this when it uses early_memtest()
2956 during boot process.
2960 depends on ARCH_USE_MEMTEST
2962 This option adds a kernel parameter 'memtest', which allows memtest
2963 to be set and executed.
2964 memtest=0, mean disabled; -- default
2965 memtest=1, mean do 1 test pattern;
2967 memtest=17, mean do 17 test patterns.
2968 If you are unsure how to answer this question, answer N.
2972 config HYPERV_TESTING
2973 bool "Microsoft Hyper-V driver testing"
2975 depends on HYPERV && DEBUG_FS
2977 Select this option to enable Hyper-V vmbus testing.
2979 endmenu # "Kernel Testing and Coverage"
2983 config RUST_DEBUG_ASSERTIONS
2984 bool "Debug assertions"
2987 Enables rustc's `-Cdebug-assertions` codegen option.
2989 This flag lets you turn `cfg(debug_assertions)` conditional
2990 compilation on or off. This can be used to enable extra debugging
2991 code in development but not in production. For example, it controls
2992 the behavior of the standard library's `debug_assert!` macro.
2994 Note that this will apply to all Rust code, including `core`.
2998 config RUST_OVERFLOW_CHECKS
2999 bool "Overflow checks"
3003 Enables rustc's `-Coverflow-checks` codegen option.
3005 This flag allows you to control the behavior of runtime integer
3006 overflow. When overflow-checks are enabled, a Rust panic will occur
3009 Note that this will apply to all Rust code, including `core`.
3013 config RUST_BUILD_ASSERT_ALLOW
3014 bool "Allow unoptimized build-time assertions"
3017 Controls how are `build_error!` and `build_assert!` handled during build.
3019 If calls to them exist in the binary, it may indicate a violated invariant
3020 or that the optimizer failed to verify the invariant during compilation.
3022 This should not happen, thus by default the build is aborted. However,
3023 as an escape hatch, you can choose Y here to ignore them during build
3024 and let the check be carried at runtime (with `panic!` being called if
3029 config RUST_KERNEL_DOCTESTS
3030 bool "Doctests for the `kernel` crate" if !KUNIT_ALL_TESTS
3031 depends on RUST && KUNIT=y
3032 default KUNIT_ALL_TESTS
3034 This builds the documentation tests of the `kernel` crate
3037 For more information on KUnit and unit tests in general,
3038 please refer to the KUnit documentation in Documentation/dev-tools/kunit/.
3044 endmenu # Kernel hacking
projects / linux-2.6-microblaze.git / blob