Dave Hansen | 604ff0d | 2013-07-01 13:04:49 -0700 | [diff] [blame] | 1 | menu "printk and dmesg options" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | |
| 3 | config PRINTK_TIME |
| 4 | bool "Show timing information on printks" |
Randy Dunlap | d3b8b6e | 2006-12-06 20:36:38 -0800 | [diff] [blame] | 5 | depends on PRINTK |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 6 | help |
Kay Sievers | 649e6ee | 2012-05-10 04:30:45 +0200 | [diff] [blame] | 7 | Selecting this option causes time stamps of the printk() |
| 8 | messages to be added to the output of the syslog() system |
| 9 | call and at the console. |
| 10 | |
| 11 | The timestamp is always recorded internally, and exported |
| 12 | to /dev/kmsg. This flag just specifies if the timestamp should |
| 13 | be included, not that the timestamp is recorded. |
| 14 | |
| 15 | The behavior is also controlled by the kernel command line |
| 16 | parameter printk.time=1. See Documentation/kernel-parameters.txt |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 17 | |
Mandeep Singh Baines | 5af5bcb | 2011-03-22 16:34:23 -0700 | [diff] [blame] | 18 | config DEFAULT_MESSAGE_LOGLEVEL |
| 19 | int "Default message log level (1-7)" |
| 20 | range 1 7 |
| 21 | default "4" |
| 22 | help |
| 23 | Default log level for printk statements with no specified priority. |
| 24 | |
| 25 | This was hard-coded to KERN_WARNING since at least 2.6.10 but folks |
| 26 | that are auditing their logs closely may want to set it to a lower |
| 27 | priority. |
| 28 | |
Dave Hansen | 604ff0d | 2013-07-01 13:04:49 -0700 | [diff] [blame] | 29 | config BOOT_PRINTK_DELAY |
| 30 | bool "Delay each boot printk message by N milliseconds" |
| 31 | depends on DEBUG_KERNEL && PRINTK && GENERIC_CALIBRATE_DELAY |
| 32 | help |
| 33 | This build option allows you to read kernel boot messages |
| 34 | by inserting a short delay after each one. The delay is |
| 35 | specified in milliseconds on the kernel command line, |
| 36 | using "boot_delay=N". |
| 37 | |
| 38 | It is likely that you would also need to use "lpj=M" to preset |
| 39 | the "loops per jiffie" value. |
| 40 | See a previous boot log for the "lpj" value to use for your |
| 41 | system, and then set "lpj=M" before setting "boot_delay=N". |
| 42 | NOTE: Using this option may adversely affect SMP systems. |
| 43 | I.e., processors other than the first one may not boot up. |
| 44 | BOOT_PRINTK_DELAY also may cause LOCKUP_DETECTOR to detect |
| 45 | what it believes to be lockup conditions. |
| 46 | |
| 47 | config DYNAMIC_DEBUG |
| 48 | bool "Enable dynamic printk() support" |
| 49 | default n |
| 50 | depends on PRINTK |
| 51 | depends on DEBUG_FS |
| 52 | help |
| 53 | |
| 54 | Compiles debug level messages into the kernel, which would not |
| 55 | otherwise be available at runtime. These messages can then be |
| 56 | enabled/disabled based on various levels of scope - per source file, |
| 57 | function, module, format string, and line number. This mechanism |
| 58 | implicitly compiles in all pr_debug() and dev_dbg() calls, which |
| 59 | enlarges the kernel text size by about 2%. |
| 60 | |
| 61 | If a source file is compiled with DEBUG flag set, any |
| 62 | pr_debug() calls in it are enabled by default, but can be |
| 63 | disabled at runtime as below. Note that DEBUG flag is |
| 64 | turned on by many CONFIG_*DEBUG* options. |
| 65 | |
| 66 | Usage: |
| 67 | |
| 68 | Dynamic debugging is controlled via the 'dynamic_debug/control' file, |
| 69 | which is contained in the 'debugfs' filesystem. Thus, the debugfs |
| 70 | filesystem must first be mounted before making use of this feature. |
| 71 | We refer the control file as: <debugfs>/dynamic_debug/control. This |
| 72 | file contains a list of the debug statements that can be enabled. The |
| 73 | format for each line of the file is: |
| 74 | |
| 75 | filename:lineno [module]function flags format |
| 76 | |
| 77 | filename : source file of the debug statement |
| 78 | lineno : line number of the debug statement |
| 79 | module : module that contains the debug statement |
| 80 | function : function that contains the debug statement |
| 81 | flags : '=p' means the line is turned 'on' for printing |
| 82 | format : the format used for the debug statement |
| 83 | |
| 84 | From a live system: |
| 85 | |
| 86 | nullarbor:~ # cat <debugfs>/dynamic_debug/control |
| 87 | # filename:lineno [module]function flags format |
| 88 | fs/aio.c:222 [aio]__put_ioctx =_ "__put_ioctx:\040freeing\040%p\012" |
| 89 | fs/aio.c:248 [aio]ioctx_alloc =_ "ENOMEM:\040nr_events\040too\040high\012" |
| 90 | fs/aio.c:1770 [aio]sys_io_cancel =_ "calling\040cancel\012" |
| 91 | |
| 92 | Example usage: |
| 93 | |
| 94 | // enable the message at line 1603 of file svcsock.c |
| 95 | nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > |
| 96 | <debugfs>/dynamic_debug/control |
| 97 | |
| 98 | // enable all the messages in file svcsock.c |
| 99 | nullarbor:~ # echo -n 'file svcsock.c +p' > |
| 100 | <debugfs>/dynamic_debug/control |
| 101 | |
| 102 | // enable all the messages in the NFS server module |
| 103 | nullarbor:~ # echo -n 'module nfsd +p' > |
| 104 | <debugfs>/dynamic_debug/control |
| 105 | |
| 106 | // enable all 12 messages in the function svc_process() |
| 107 | nullarbor:~ # echo -n 'func svc_process +p' > |
| 108 | <debugfs>/dynamic_debug/control |
| 109 | |
| 110 | // disable all 12 messages in the function svc_process() |
| 111 | nullarbor:~ # echo -n 'func svc_process -p' > |
| 112 | <debugfs>/dynamic_debug/control |
| 113 | |
| 114 | See Documentation/dynamic-debug-howto.txt for additional information. |
| 115 | |
| 116 | endmenu # "printk and dmesg options" |
| 117 | |
Dave Hansen | 6dfc066 | 2013-07-01 13:04:46 -0700 | [diff] [blame] | 118 | menu "Compile-time checks and compiler options" |
| 119 | |
| 120 | config DEBUG_INFO |
| 121 | bool "Compile the kernel with debug info" |
Linus Torvalds | 12b1383 | 2014-02-04 12:20:01 -0800 | [diff] [blame] | 122 | depends on DEBUG_KERNEL && !COMPILE_TEST |
Dave Hansen | 6dfc066 | 2013-07-01 13:04:46 -0700 | [diff] [blame] | 123 | help |
| 124 | If you say Y here the resulting kernel image will include |
| 125 | debugging info resulting in a larger kernel image. |
| 126 | This adds debug symbols to the kernel and modules (gcc -g), and |
| 127 | is needed if you intend to use kernel crashdump or binary object |
| 128 | tools like crash, kgdb, LKCD, gdb, etc on the kernel. |
| 129 | Say Y here only if you plan to debug the kernel. |
| 130 | |
| 131 | If unsure, say N. |
| 132 | |
| 133 | config DEBUG_INFO_REDUCED |
| 134 | bool "Reduce debugging information" |
| 135 | depends on DEBUG_INFO |
| 136 | help |
| 137 | If you say Y here gcc is instructed to generate less debugging |
| 138 | information for structure types. This means that tools that |
| 139 | need full debugging information (like kgdb or systemtap) won't |
| 140 | be happy. But if you merely need debugging information to |
| 141 | resolve line numbers there is no loss. Advantage is that |
| 142 | build directory object sizes shrink dramatically over a full |
| 143 | DEBUG_INFO build and compile times are reduced too. |
| 144 | Only works with newer gcc versions. |
| 145 | |
Andi Kleen | 866ced9 | 2014-07-30 20:50:18 +0200 | [diff] [blame^] | 146 | config DEBUG_INFO_SPLIT |
| 147 | bool "Produce split debuginfo in .dwo files" |
| 148 | depends on DEBUG_INFO |
| 149 | help |
| 150 | Generate debug info into separate .dwo files. This significantly |
| 151 | reduces the build directory size for builds with DEBUG_INFO, |
| 152 | because it stores the information only once on disk in .dwo |
| 153 | files instead of multiple times in object files and executables. |
| 154 | In addition the debug information is also compressed. |
| 155 | |
| 156 | Requires recent gcc (4.7+) and recent gdb/binutils. |
| 157 | Any tool that packages or reads debug information would need |
| 158 | to know about the .dwo files and include them. |
| 159 | Incompatible with older versions of ccache. |
| 160 | |
Jeff Garzik | de48844 | 2007-10-25 04:06:13 -0400 | [diff] [blame] | 161 | config ENABLE_WARN_DEPRECATED |
| 162 | bool "Enable __deprecated logic" |
| 163 | default y |
| 164 | help |
| 165 | Enable the __deprecated logic in the kernel build. |
| 166 | Disable this to suppress the "warning: 'foo' is deprecated |
| 167 | (declared at kernel/power/somefile.c:1234)" messages. |
| 168 | |
Andrew Morton | cebc04b | 2006-08-14 22:43:18 -0700 | [diff] [blame] | 169 | config ENABLE_MUST_CHECK |
| 170 | bool "Enable __must_check logic" |
| 171 | default y |
| 172 | help |
| 173 | Enable the __must_check logic in the kernel build. Disable this to |
| 174 | suppress the "warning: ignoring return value of 'foo', declared with |
| 175 | attribute warn_unused_result" messages. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 176 | |
Andi Kleen | 35bb5b1 | 2008-02-22 15:15:03 +0100 | [diff] [blame] | 177 | config FRAME_WARN |
| 178 | int "Warn for stack frames larger than (needs gcc 4.4)" |
| 179 | range 0 8192 |
| 180 | default 1024 if !64BIT |
| 181 | default 2048 if 64BIT |
| 182 | help |
| 183 | Tell gcc to warn at build time for stack frames larger than this. |
| 184 | Setting this too low will cause a lot of warnings. |
| 185 | Setting it to 0 disables the warning. |
| 186 | Requires gcc 4.4 |
| 187 | |
Randy Dunlap | 99657c7 | 2009-09-18 12:49:22 -0700 | [diff] [blame] | 188 | config STRIP_ASM_SYMS |
| 189 | bool "Strip assembler-generated symbols during link" |
| 190 | default n |
| 191 | help |
| 192 | Strip internal assembler-generated symbols during a link (symbols |
| 193 | that look like '.Lxxx') so they don't pollute the output of |
| 194 | get_wchan() and suchlike. |
| 195 | |
Andi Kleen | 1873e87 | 2012-03-28 11:51:18 -0700 | [diff] [blame] | 196 | config READABLE_ASM |
| 197 | bool "Generate readable assembler code" |
| 198 | depends on DEBUG_KERNEL |
| 199 | help |
| 200 | Disable some compiler optimizations that tend to generate human unreadable |
| 201 | assembler output. This may make the kernel slightly slower, but it helps |
| 202 | to keep kernel developers who have to stare a lot at assembler listings |
| 203 | sane. |
| 204 | |
Arjan van de Ven | f71d20e | 2006-06-28 04:26:45 -0700 | [diff] [blame] | 205 | config UNUSED_SYMBOLS |
| 206 | bool "Enable unused/obsolete exported symbols" |
| 207 | default y if X86 |
| 208 | help |
| 209 | Unused but exported symbols make the kernel needlessly bigger. For |
| 210 | that reason most of these unused exports will soon be removed. This |
| 211 | option is provided temporarily to provide a transition period in case |
| 212 | some external kernel module needs one of these symbols anyway. If you |
| 213 | encounter such a case in your module, consider if you are actually |
| 214 | using the right API. (rationale: since nobody in the kernel is using |
| 215 | this in a module, there is a pretty good chance it's actually the |
| 216 | wrong interface to use). If you really need the symbol, please send a |
| 217 | mail to the linux kernel mailing list mentioning the symbol and why |
| 218 | you really need it, and what the merge plan to the mainline kernel for |
| 219 | your module is. |
| 220 | |
Don Mullis | bf4735a | 2006-12-10 02:18:37 -0800 | [diff] [blame] | 221 | config DEBUG_FS |
| 222 | bool "Debug Filesystem" |
Don Mullis | bf4735a | 2006-12-10 02:18:37 -0800 | [diff] [blame] | 223 | help |
| 224 | debugfs is a virtual file system that kernel developers use to put |
| 225 | debugging files into. Enable this option to be able to read and |
| 226 | write to these files. |
| 227 | |
Robert P. J. Day | ff54333 | 2008-05-20 00:06:00 +0200 | [diff] [blame] | 228 | For detailed documentation on the debugfs API, see |
| 229 | Documentation/DocBook/filesystems. |
| 230 | |
Don Mullis | bf4735a | 2006-12-10 02:18:37 -0800 | [diff] [blame] | 231 | If unsure, say N. |
| 232 | |
| 233 | config HEADERS_CHECK |
| 234 | bool "Run 'make headers_check' when building vmlinux" |
| 235 | depends on !UML |
| 236 | help |
| 237 | This option will extract the user-visible kernel headers whenever |
| 238 | building the kernel, and will run basic sanity checks on them to |
| 239 | ensure that exported files do not attempt to include files which |
| 240 | were not exported, etc. |
| 241 | |
| 242 | If you're making modifications to header files which are |
| 243 | relevant for userspace, say 'Y', and check the headers |
| 244 | exported to $(INSTALL_HDR_PATH) (usually 'usr/include' in |
| 245 | your build tree), to make sure they're suitable. |
| 246 | |
Sam Ravnborg | 91341d4 | 2008-01-21 21:31:44 +0100 | [diff] [blame] | 247 | config DEBUG_SECTION_MISMATCH |
| 248 | bool "Enable full Section mismatch analysis" |
Sam Ravnborg | 91341d4 | 2008-01-21 21:31:44 +0100 | [diff] [blame] | 249 | help |
| 250 | The section mismatch analysis checks if there are illegal |
| 251 | references from one section to another section. |
Michael Witten | e809ab0 | 2011-04-17 04:08:48 +0000 | [diff] [blame] | 252 | During linktime or runtime, some sections are dropped; |
| 253 | any use of code/data previously in these sections would |
Sam Ravnborg | 91341d4 | 2008-01-21 21:31:44 +0100 | [diff] [blame] | 254 | most likely result in an oops. |
Michael Witten | e809ab0 | 2011-04-17 04:08:48 +0000 | [diff] [blame] | 255 | In the code, functions and variables are annotated with |
Paul Gortmaker | 0db0628 | 2013-06-19 14:53:51 -0400 | [diff] [blame] | 256 | __init,, etc. (see the full list in include/linux/init.h), |
Geert Uytterhoeven | d6fbfa4 | 2008-01-30 11:13:23 +0100 | [diff] [blame] | 257 | which results in the code/data being placed in specific sections. |
Michael Witten | e809ab0 | 2011-04-17 04:08:48 +0000 | [diff] [blame] | 258 | The section mismatch analysis is always performed after a full |
| 259 | kernel build, and enabling this option causes the following |
| 260 | additional steps to occur: |
| 261 | - Add the option -fno-inline-functions-called-once to gcc commands. |
| 262 | When inlining a function annotated with __init in a non-init |
| 263 | function, we would lose the section information and thus |
Sam Ravnborg | 91341d4 | 2008-01-21 21:31:44 +0100 | [diff] [blame] | 264 | the analysis would not catch the illegal reference. |
Michael Witten | e809ab0 | 2011-04-17 04:08:48 +0000 | [diff] [blame] | 265 | This option tells gcc to inline less (but it does result in |
| 266 | a larger kernel). |
| 267 | - Run the section mismatch analysis for each module/built-in.o file. |
| 268 | When we run the section mismatch analysis on vmlinux.o, we |
Geert Uytterhoeven | d6fbfa4 | 2008-01-30 11:13:23 +0100 | [diff] [blame] | 269 | lose valueble information about where the mismatch was |
Sam Ravnborg | 91341d4 | 2008-01-21 21:31:44 +0100 | [diff] [blame] | 270 | introduced. |
| 271 | Running the analysis for each module/built-in.o file |
Michael Witten | e809ab0 | 2011-04-17 04:08:48 +0000 | [diff] [blame] | 272 | tells where the mismatch happens much closer to the |
| 273 | source. The drawback is that the same mismatch is |
| 274 | reported at least twice. |
| 275 | - Enable verbose reporting from modpost in order to help resolve |
| 276 | the section mismatches that are reported. |
Sam Ravnborg | 91341d4 | 2008-01-21 21:31:44 +0100 | [diff] [blame] | 277 | |
Dave Hansen | 6dfc066 | 2013-07-01 13:04:46 -0700 | [diff] [blame] | 278 | # |
| 279 | # Select this config option from the architecture Kconfig, if it |
| 280 | # is preferred to always offer frame pointers as a config |
| 281 | # option on the architecture (regardless of KERNEL_DEBUG): |
| 282 | # |
| 283 | config ARCH_WANT_FRAME_POINTERS |
| 284 | bool |
| 285 | help |
| 286 | |
| 287 | config FRAME_POINTER |
| 288 | bool "Compile the kernel with frame pointers" |
| 289 | depends on DEBUG_KERNEL && \ |
| 290 | (CRIS || M68K || FRV || UML || \ |
| 291 | AVR32 || SUPERH || BLACKFIN || MN10300 || METAG) || \ |
| 292 | ARCH_WANT_FRAME_POINTERS |
| 293 | default y if (DEBUG_INFO && UML) || ARCH_WANT_FRAME_POINTERS |
| 294 | help |
| 295 | If you say Y here the resulting kernel image will be slightly |
| 296 | larger and slower, but it gives very useful debugging information |
| 297 | in case of kernel bugs. (precise oopses/stacktraces/warnings) |
| 298 | |
| 299 | config DEBUG_FORCE_WEAK_PER_CPU |
| 300 | bool "Force weak per-cpu definitions" |
| 301 | depends on DEBUG_KERNEL |
| 302 | help |
| 303 | s390 and alpha require percpu variables in modules to be |
| 304 | defined weak to work around addressing range issue which |
| 305 | puts the following two restrictions on percpu variable |
| 306 | definitions. |
| 307 | |
| 308 | 1. percpu symbols must be unique whether static or not |
| 309 | 2. percpu variables can't be defined inside a function |
| 310 | |
| 311 | To ensure that generic code follows the above rules, this |
| 312 | option forces all percpu variables to be defined as weak. |
| 313 | |
| 314 | endmenu # "Compiler options" |
| 315 | |
| 316 | config MAGIC_SYSRQ |
| 317 | bool "Magic SysRq key" |
| 318 | depends on !UML |
| 319 | help |
| 320 | If you say Y here, you will have some control over the system even |
| 321 | if the system crashes for example during kernel debugging (e.g., you |
| 322 | will be able to flush the buffer cache to disk, reboot the system |
| 323 | immediately or dump some status information). This is accomplished |
| 324 | by pressing various keys while holding SysRq (Alt+PrintScreen). It |
| 325 | also works on a serial console (on PC hardware at least), if you |
| 326 | send a BREAK and then within 5 seconds a command keypress. The |
| 327 | keys are documented in <file:Documentation/sysrq.txt>. Don't say Y |
| 328 | unless you really know what this hack does. |
| 329 | |
Ben Hutchings | 8eaede4 | 2013-10-07 01:05:46 +0100 | [diff] [blame] | 330 | config MAGIC_SYSRQ_DEFAULT_ENABLE |
| 331 | hex "Enable magic SysRq key functions by default" |
| 332 | depends on MAGIC_SYSRQ |
| 333 | default 0x1 |
| 334 | help |
| 335 | Specifies which SysRq key functions are enabled by default. |
| 336 | This may be set to 1 or 0 to enable or disable them all, or |
| 337 | to a bitmask as described in Documentation/sysrq.txt. |
| 338 | |
Adrian Bunk | f346f4b | 2006-01-09 20:54:51 -0800 | [diff] [blame] | 339 | config DEBUG_KERNEL |
| 340 | bool "Kernel debugging" |
| 341 | help |
| 342 | Say Y here if you are developing drivers or trying to debug and |
| 343 | identify kernel problems. |
| 344 | |
Dave Hansen | 0610c8a | 2013-07-01 13:04:43 -0700 | [diff] [blame] | 345 | menu "Memory Debugging" |
David Woodhouse | a304e1b | 2007-02-12 00:52:00 -0800 | [diff] [blame] | 346 | |
Dave Hansen | 0610c8a | 2013-07-01 13:04:43 -0700 | [diff] [blame] | 347 | source mm/Kconfig.debug |
Ingo Molnar | 82f67cd | 2007-02-16 01:28:13 -0800 | [diff] [blame] | 348 | |
Thomas Gleixner | 3ac7fe5 | 2008-04-30 00:55:01 -0700 | [diff] [blame] | 349 | config DEBUG_OBJECTS |
| 350 | bool "Debug object operations" |
| 351 | depends on DEBUG_KERNEL |
| 352 | help |
| 353 | If you say Y here, additional code will be inserted into the |
| 354 | kernel to track the life time of various objects and validate |
| 355 | the operations on those objects. |
| 356 | |
| 357 | config DEBUG_OBJECTS_SELFTEST |
| 358 | bool "Debug objects selftest" |
| 359 | depends on DEBUG_OBJECTS |
| 360 | help |
| 361 | This enables the selftest of the object debug code. |
| 362 | |
| 363 | config DEBUG_OBJECTS_FREE |
| 364 | bool "Debug objects in freed memory" |
| 365 | depends on DEBUG_OBJECTS |
| 366 | help |
| 367 | This enables checks whether a k/v free operation frees an area |
| 368 | which contains an object which has not been deactivated |
| 369 | properly. This can make kmalloc/kfree-intensive workloads |
| 370 | much slower. |
| 371 | |
Thomas Gleixner | c6f3a97 | 2008-04-30 00:55:03 -0700 | [diff] [blame] | 372 | config DEBUG_OBJECTS_TIMERS |
| 373 | bool "Debug timer objects" |
| 374 | depends on DEBUG_OBJECTS |
| 375 | help |
| 376 | If you say Y here, additional code will be inserted into the |
| 377 | timer routines to track the life time of timer objects and |
| 378 | validate the timer operations. |
| 379 | |
Thomas Gleixner | dc186ad | 2009-11-16 01:09:48 +0900 | [diff] [blame] | 380 | config DEBUG_OBJECTS_WORK |
| 381 | bool "Debug work objects" |
| 382 | depends on DEBUG_OBJECTS |
| 383 | help |
| 384 | If you say Y here, additional code will be inserted into the |
| 385 | work queue routines to track the life time of work objects and |
| 386 | validate the work operations. |
| 387 | |
Mathieu Desnoyers | 551d55a | 2010-04-17 08:48:42 -0400 | [diff] [blame] | 388 | config DEBUG_OBJECTS_RCU_HEAD |
| 389 | bool "Debug RCU callbacks objects" |
Mathieu Desnoyers | fc2ecf7 | 2011-02-23 09:42:14 -0800 | [diff] [blame] | 390 | depends on DEBUG_OBJECTS |
Mathieu Desnoyers | 551d55a | 2010-04-17 08:48:42 -0400 | [diff] [blame] | 391 | help |
| 392 | Enable this to turn on debugging of RCU list heads (call_rcu() usage). |
| 393 | |
Tejun Heo | e2852ae | 2010-10-26 14:23:05 -0700 | [diff] [blame] | 394 | config DEBUG_OBJECTS_PERCPU_COUNTER |
| 395 | bool "Debug percpu counter objects" |
| 396 | depends on DEBUG_OBJECTS |
| 397 | help |
| 398 | If you say Y here, additional code will be inserted into the |
| 399 | percpu counter routines to track the life time of percpu counter |
| 400 | objects and validate the percpu counter operations. |
| 401 | |
Ingo Molnar | 3ae7020 | 2008-11-26 10:02:00 +0100 | [diff] [blame] | 402 | config DEBUG_OBJECTS_ENABLE_DEFAULT |
| 403 | int "debug_objects bootup default value (0-1)" |
| 404 | range 0 1 |
| 405 | default "1" |
| 406 | depends on DEBUG_OBJECTS |
| 407 | help |
| 408 | Debug objects boot parameter default value |
| 409 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 410 | config DEBUG_SLAB |
Andrew Morton | 4a2f0ac | 2006-03-25 03:07:22 -0800 | [diff] [blame] | 411 | bool "Debug slab memory allocations" |
Vegard Nossum | 7d46d9e | 2008-04-04 00:51:41 +0200 | [diff] [blame] | 412 | depends on DEBUG_KERNEL && SLAB && !KMEMCHECK |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 413 | help |
| 414 | Say Y here to have the kernel do limited verification on memory |
| 415 | allocation as well as poisoning memory on free to catch use of freed |
| 416 | memory. This can make kmalloc/kfree-intensive workloads much slower. |
| 417 | |
Al Viro | 871751e | 2006-03-25 03:06:39 -0800 | [diff] [blame] | 418 | config DEBUG_SLAB_LEAK |
| 419 | bool "Memory leak debugging" |
| 420 | depends on DEBUG_SLAB |
| 421 | |
Christoph Lameter | f0630ff | 2007-07-15 23:38:14 -0700 | [diff] [blame] | 422 | config SLUB_DEBUG_ON |
| 423 | bool "SLUB debugging on by default" |
Vegard Nossum | 7d46d9e | 2008-04-04 00:51:41 +0200 | [diff] [blame] | 424 | depends on SLUB && SLUB_DEBUG && !KMEMCHECK |
Christoph Lameter | f0630ff | 2007-07-15 23:38:14 -0700 | [diff] [blame] | 425 | default n |
| 426 | help |
| 427 | Boot with debugging on by default. SLUB boots by default with |
| 428 | the runtime debug capabilities switched off. Enabling this is |
| 429 | equivalent to specifying the "slub_debug" parameter on boot. |
| 430 | There is no support for more fine grained debug control like |
| 431 | possible with slub_debug=xxx. SLUB debugging may be switched |
| 432 | off in a kernel built with CONFIG_SLUB_DEBUG_ON by specifying |
| 433 | "slub_debug=-". |
| 434 | |
Christoph Lameter | 8ff12cf | 2008-02-07 17:47:41 -0800 | [diff] [blame] | 435 | config SLUB_STATS |
| 436 | default n |
| 437 | bool "Enable SLUB performance statistics" |
Christoph Lameter | ab4d5ed | 2010-10-05 13:57:26 -0500 | [diff] [blame] | 438 | depends on SLUB && SYSFS |
Christoph Lameter | 8ff12cf | 2008-02-07 17:47:41 -0800 | [diff] [blame] | 439 | help |
| 440 | SLUB statistics are useful to debug SLUBs allocation behavior in |
| 441 | order find ways to optimize the allocator. This should never be |
| 442 | enabled for production use since keeping statistics slows down |
| 443 | the allocator by a few percentage points. The slabinfo command |
| 444 | supports the determination of the most active slabs to figure |
| 445 | out which slabs are relevant to a particular load. |
| 446 | Try running: slabinfo -DA |
| 447 | |
Catalin Marinas | b69ec42 | 2012-10-08 16:28:11 -0700 | [diff] [blame] | 448 | config HAVE_DEBUG_KMEMLEAK |
| 449 | bool |
| 450 | |
Catalin Marinas | 3bba00d | 2009-06-11 13:24:13 +0100 | [diff] [blame] | 451 | config DEBUG_KMEMLEAK |
| 452 | bool "Kernel memory leak detector" |
Kees Cook | 525c1f9 | 2013-01-16 18:54:16 -0800 | [diff] [blame] | 453 | depends on DEBUG_KERNEL && HAVE_DEBUG_KMEMLEAK |
Catalin Marinas | 79e0d9b | 2011-04-27 17:06:19 +0100 | [diff] [blame] | 454 | select DEBUG_FS |
Catalin Marinas | 3bba00d | 2009-06-11 13:24:13 +0100 | [diff] [blame] | 455 | select STACKTRACE if STACKTRACE_SUPPORT |
| 456 | select KALLSYMS |
Randy Dunlap | b60e26a | 2009-11-06 15:33:45 -0800 | [diff] [blame] | 457 | select CRC32 |
Catalin Marinas | 3bba00d | 2009-06-11 13:24:13 +0100 | [diff] [blame] | 458 | help |
| 459 | Say Y here if you want to enable the memory leak |
| 460 | detector. The memory allocation/freeing is traced in a way |
| 461 | similar to the Boehm's conservative garbage collector, the |
| 462 | difference being that the orphan objects are not freed but |
| 463 | only shown in /sys/kernel/debug/kmemleak. Enabling this |
| 464 | feature will introduce an overhead to memory |
| 465 | allocations. See Documentation/kmemleak.txt for more |
| 466 | details. |
| 467 | |
Catalin Marinas | bf96d1e | 2009-06-23 14:40:27 +0100 | [diff] [blame] | 468 | Enabling DEBUG_SLAB or SLUB_DEBUG may increase the chances |
| 469 | of finding leaks due to the slab objects poisoning. |
| 470 | |
Catalin Marinas | 3bba00d | 2009-06-11 13:24:13 +0100 | [diff] [blame] | 471 | In order to access the kmemleak file, debugfs needs to be |
| 472 | mounted (usually at /sys/kernel/debug). |
| 473 | |
Catalin Marinas | a9d9058 | 2009-06-25 10:16:11 +0100 | [diff] [blame] | 474 | config DEBUG_KMEMLEAK_EARLY_LOG_SIZE |
| 475 | int "Maximum kmemleak early log entries" |
| 476 | depends on DEBUG_KMEMLEAK |
Heiko Carstens | dfcc3e6 | 2009-10-06 10:33:57 +0200 | [diff] [blame] | 477 | range 200 40000 |
Catalin Marinas | a9d9058 | 2009-06-25 10:16:11 +0100 | [diff] [blame] | 478 | default 400 |
| 479 | help |
| 480 | Kmemleak must track all the memory allocations to avoid |
| 481 | reporting false positives. Since memory may be allocated or |
| 482 | freed before kmemleak is initialised, an early log buffer is |
| 483 | used to store these actions. If kmemleak reports "early log |
| 484 | buffer exceeded", please increase this value. |
| 485 | |
Catalin Marinas | 0822ee4 | 2009-06-11 13:24:14 +0100 | [diff] [blame] | 486 | config DEBUG_KMEMLEAK_TEST |
| 487 | tristate "Simple test for the kernel memory leak detector" |
Daniel Baluta | 9718269 | 2011-04-04 15:06:44 -0700 | [diff] [blame] | 488 | depends on DEBUG_KMEMLEAK && m |
Catalin Marinas | 0822ee4 | 2009-06-11 13:24:14 +0100 | [diff] [blame] | 489 | help |
Daniel Baluta | 9718269 | 2011-04-04 15:06:44 -0700 | [diff] [blame] | 490 | This option enables a module that explicitly leaks memory. |
Catalin Marinas | 0822ee4 | 2009-06-11 13:24:14 +0100 | [diff] [blame] | 491 | |
| 492 | If unsure, say N. |
| 493 | |
Jason Baron | ab0155a | 2010-07-19 11:54:17 +0100 | [diff] [blame] | 494 | config DEBUG_KMEMLEAK_DEFAULT_OFF |
| 495 | bool "Default kmemleak to off" |
| 496 | depends on DEBUG_KMEMLEAK |
| 497 | help |
| 498 | Say Y here to disable kmemleak by default. It can then be enabled |
| 499 | on the command line via kmemleak=on. |
| 500 | |
Dave Hansen | 0610c8a | 2013-07-01 13:04:43 -0700 | [diff] [blame] | 501 | config DEBUG_STACK_USAGE |
| 502 | bool "Stack utilization instrumentation" |
| 503 | depends on DEBUG_KERNEL && !IA64 && !PARISC && !METAG |
| 504 | help |
| 505 | Enables the display of the minimum amount of free stack which each |
| 506 | task has ever had available in the sysrq-T and sysrq-P debug output. |
| 507 | |
| 508 | This option will slow down process creation somewhat. |
| 509 | |
| 510 | config DEBUG_VM |
| 511 | bool "Debug VM" |
| 512 | depends on DEBUG_KERNEL |
| 513 | help |
| 514 | Enable this to turn on extended checks in the virtual-memory system |
| 515 | that may impact performance. |
| 516 | |
| 517 | If unsure, say N. |
| 518 | |
Davidlohr Bueso | 4f11514 | 2014-06-04 16:06:46 -0700 | [diff] [blame] | 519 | config DEBUG_VM_VMACACHE |
| 520 | bool "Debug VMA caching" |
| 521 | depends on DEBUG_VM |
| 522 | help |
| 523 | Enable this to turn on VMA caching debug information. Doing so |
| 524 | can cause significant overhead, so only enable it in non-production |
| 525 | environments. |
| 526 | |
| 527 | If unsure, say N. |
| 528 | |
Dave Hansen | 0610c8a | 2013-07-01 13:04:43 -0700 | [diff] [blame] | 529 | config DEBUG_VM_RB |
| 530 | bool "Debug VM red-black trees" |
| 531 | depends on DEBUG_VM |
| 532 | help |
Davidlohr Bueso | a663dad | 2014-04-18 15:07:22 -0700 | [diff] [blame] | 533 | Enable VM red-black tree debugging information and extra validations. |
Dave Hansen | 0610c8a | 2013-07-01 13:04:43 -0700 | [diff] [blame] | 534 | |
| 535 | If unsure, say N. |
| 536 | |
| 537 | config DEBUG_VIRTUAL |
| 538 | bool "Debug VM translations" |
| 539 | depends on DEBUG_KERNEL && X86 |
| 540 | help |
| 541 | Enable some costly sanity checks in virtual to page code. This can |
| 542 | catch mistakes with virt_to_page() and friends. |
| 543 | |
| 544 | If unsure, say N. |
| 545 | |
| 546 | config DEBUG_NOMMU_REGIONS |
| 547 | bool "Debug the global anon/private NOMMU mapping region tree" |
| 548 | depends on DEBUG_KERNEL && !MMU |
| 549 | help |
| 550 | This option causes the global tree of anonymous and private mapping |
| 551 | regions to be regularly checked for invalid topology. |
| 552 | |
| 553 | config DEBUG_MEMORY_INIT |
| 554 | bool "Debug memory initialisation" if EXPERT |
| 555 | default !EXPERT |
| 556 | help |
| 557 | Enable this for additional checks during memory initialisation. |
| 558 | The sanity checks verify aspects of the VM such as the memory model |
| 559 | and other information provided by the architecture. Verbose |
| 560 | information will be printed at KERN_DEBUG loglevel depending |
| 561 | on the mminit_loglevel= command-line option. |
| 562 | |
| 563 | If unsure, say Y |
| 564 | |
| 565 | config MEMORY_NOTIFIER_ERROR_INJECT |
| 566 | tristate "Memory hotplug notifier error injection module" |
| 567 | depends on MEMORY_HOTPLUG_SPARSE && NOTIFIER_ERROR_INJECTION |
| 568 | help |
| 569 | This option provides the ability to inject artificial errors to |
| 570 | memory hotplug notifier chain callbacks. It is controlled through |
| 571 | debugfs interface under /sys/kernel/debug/notifier-error-inject/memory |
| 572 | |
| 573 | If the notifier call chain should be failed with some events |
| 574 | notified, write the error code to "actions/<notifier event>/error". |
| 575 | |
| 576 | Example: Inject memory hotplug offline error (-12 == -ENOMEM) |
| 577 | |
| 578 | # cd /sys/kernel/debug/notifier-error-inject/memory |
| 579 | # echo -12 > actions/MEM_GOING_OFFLINE/error |
| 580 | # echo offline > /sys/devices/system/memory/memoryXXX/state |
| 581 | bash: echo: write error: Cannot allocate memory |
| 582 | |
| 583 | To compile this code as a module, choose M here: the module will |
| 584 | be called memory-notifier-error-inject. |
| 585 | |
| 586 | If unsure, say N. |
| 587 | |
| 588 | config DEBUG_PER_CPU_MAPS |
| 589 | bool "Debug access to per_cpu maps" |
| 590 | depends on DEBUG_KERNEL |
| 591 | depends on SMP |
| 592 | help |
| 593 | Say Y to verify that the per_cpu map being accessed has |
| 594 | been set up. This adds a fair amount of code to kernel memory |
| 595 | and decreases performance. |
| 596 | |
| 597 | Say N if unsure. |
| 598 | |
| 599 | config DEBUG_HIGHMEM |
| 600 | bool "Highmem debugging" |
| 601 | depends on DEBUG_KERNEL && HIGHMEM |
| 602 | help |
Geert Uytterhoeven | b1357c9 | 2014-04-14 18:55:50 +0200 | [diff] [blame] | 603 | This option enables additional error checking for high memory |
| 604 | systems. Disable for production systems. |
Dave Hansen | 0610c8a | 2013-07-01 13:04:43 -0700 | [diff] [blame] | 605 | |
| 606 | config HAVE_DEBUG_STACKOVERFLOW |
| 607 | bool |
| 608 | |
| 609 | config DEBUG_STACKOVERFLOW |
| 610 | bool "Check for stack overflows" |
| 611 | depends on DEBUG_KERNEL && HAVE_DEBUG_STACKOVERFLOW |
| 612 | ---help--- |
| 613 | Say Y here if you want to check for overflows of kernel, IRQ |
| 614 | and exception stacks (if your archicture uses them). This |
| 615 | option will show detailed messages if free stack space drops |
| 616 | below a certain limit. |
| 617 | |
| 618 | These kinds of bugs usually occur when call-chains in the |
| 619 | kernel get too deep, especially when interrupts are |
| 620 | involved. |
| 621 | |
| 622 | Use this in cases where you see apparently random memory |
| 623 | corruption, especially if it appears in 'struct thread_info' |
| 624 | |
| 625 | If in doubt, say "N". |
| 626 | |
| 627 | source "lib/Kconfig.kmemcheck" |
| 628 | |
| 629 | endmenu # "Memory Debugging" |
| 630 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 631 | config DEBUG_SHIRQ |
| 632 | bool "Debug shared IRQ handlers" |
Martin Schwidefsky | 0244ad0 | 2013-08-30 09:39:53 +0200 | [diff] [blame] | 633 | depends on DEBUG_KERNEL |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 634 | help |
| 635 | Enable this to generate a spurious interrupt as soon as a shared |
| 636 | interrupt handler is registered, and just before one is deregistered. |
| 637 | Drivers ought to be able to handle interrupts coming in at those |
| 638 | points; some don't and need to be caught. |
| 639 | |
Dave Hansen | 92aef8fb | 2013-07-01 13:04:50 -0700 | [diff] [blame] | 640 | menu "Debug Lockups and Hangs" |
| 641 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 642 | config LOCKUP_DETECTOR |
| 643 | bool "Detect Hard and Soft Lockups" |
| 644 | depends on DEBUG_KERNEL && !S390 |
| 645 | help |
| 646 | Say Y here to enable the kernel to act as a watchdog to detect |
| 647 | hard and soft lockups. |
| 648 | |
| 649 | Softlockups are bugs that cause the kernel to loop in kernel |
| 650 | mode for more than 20 seconds, without giving other tasks a |
| 651 | chance to run. The current stack trace is displayed upon |
| 652 | detection and the system will stay locked up. |
| 653 | |
| 654 | Hardlockups are bugs that cause the CPU to loop in kernel mode |
| 655 | for more than 10 seconds, without letting other interrupts have a |
| 656 | chance to run. The current stack trace is displayed upon detection |
| 657 | and the system will stay locked up. |
| 658 | |
| 659 | The overhead should be minimal. A periodic hrtimer runs to |
| 660 | generate interrupts and kick the watchdog task every 4 seconds. |
| 661 | An NMI is generated every 10 seconds or so to check for hardlockups. |
| 662 | |
| 663 | The frequency of hrtimer and NMI events and the soft and hard lockup |
| 664 | thresholds can be controlled through the sysctl watchdog_thresh. |
| 665 | |
| 666 | config HARDLOCKUP_DETECTOR |
| 667 | def_bool y |
| 668 | depends on LOCKUP_DETECTOR && !HAVE_NMI_WATCHDOG |
| 669 | depends on PERF_EVENTS && HAVE_PERF_EVENTS_NMI |
| 670 | |
| 671 | config BOOTPARAM_HARDLOCKUP_PANIC |
| 672 | bool "Panic (Reboot) On Hard Lockups" |
| 673 | depends on HARDLOCKUP_DETECTOR |
| 674 | help |
| 675 | Say Y here to enable the kernel to panic on "hard lockups", |
| 676 | which are bugs that cause the kernel to loop in kernel |
| 677 | mode with interrupts disabled for more than 10 seconds (configurable |
| 678 | using the watchdog_thresh sysctl). |
| 679 | |
| 680 | Say N if unsure. |
| 681 | |
| 682 | config BOOTPARAM_HARDLOCKUP_PANIC_VALUE |
| 683 | int |
| 684 | depends on HARDLOCKUP_DETECTOR |
| 685 | range 0 1 |
| 686 | default 0 if !BOOTPARAM_HARDLOCKUP_PANIC |
| 687 | default 1 if BOOTPARAM_HARDLOCKUP_PANIC |
| 688 | |
| 689 | config BOOTPARAM_SOFTLOCKUP_PANIC |
| 690 | bool "Panic (Reboot) On Soft Lockups" |
| 691 | depends on LOCKUP_DETECTOR |
| 692 | help |
| 693 | Say Y here to enable the kernel to panic on "soft lockups", |
| 694 | which are bugs that cause the kernel to loop in kernel |
| 695 | mode for more than 20 seconds (configurable using the watchdog_thresh |
| 696 | sysctl), without giving other tasks a chance to run. |
| 697 | |
| 698 | The panic can be used in combination with panic_timeout, |
| 699 | to cause the system to reboot automatically after a |
| 700 | lockup has been detected. This feature is useful for |
| 701 | high-availability systems that have uptime guarantees and |
| 702 | where a lockup must be resolved ASAP. |
| 703 | |
Ingo Molnar | 8637c09 | 2006-07-03 00:24:38 -0700 | [diff] [blame] | 704 | Say N if unsure. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 705 | |
| 706 | config BOOTPARAM_SOFTLOCKUP_PANIC_VALUE |
| 707 | int |
| 708 | depends on LOCKUP_DETECTOR |
| 709 | range 0 1 |
| 710 | default 0 if !BOOTPARAM_SOFTLOCKUP_PANIC |
| 711 | default 1 if BOOTPARAM_SOFTLOCKUP_PANIC |
Ingo Molnar | e7eebaf | 2006-06-27 02:54:55 -0700 | [diff] [blame] | 712 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 713 | config DETECT_HUNG_TASK |
| 714 | bool "Detect Hung Tasks" |
| 715 | depends on DEBUG_KERNEL |
| 716 | default LOCKUP_DETECTOR |
| 717 | help |
| 718 | Say Y here to enable the kernel to detect "hung tasks", |
| 719 | which are bugs that cause the task to be stuck in |
| 720 | uninterruptible "D" state indefinitiley. |
| 721 | |
| 722 | When a hung task is detected, the kernel will print the |
| 723 | current stack trace (which you should report), but the |
| 724 | task will stay in uninterruptible state. If lockdep is |
| 725 | enabled then all held locks will also be reported. This |
| 726 | feature has negligible overhead. |
| 727 | |
| 728 | config DEFAULT_HUNG_TASK_TIMEOUT |
| 729 | int "Default timeout for hung task detection (in seconds)" |
| 730 | depends on DETECT_HUNG_TASK |
| 731 | default 120 |
| 732 | help |
| 733 | This option controls the default timeout (in seconds) used |
| 734 | to determine when a task has become non-responsive and should |
| 735 | be considered hung. |
| 736 | |
| 737 | It can be adjusted at runtime via the kernel.hung_task_timeout_secs |
| 738 | sysctl or by writing a value to |
| 739 | /proc/sys/kernel/hung_task_timeout_secs. |
| 740 | |
Ingo Molnar | 408894e | 2006-01-09 15:59:20 -0800 | [diff] [blame] | 741 | A timeout of 0 disables the check. The default is two minutes. |
| 742 | Keeping the default should be fine in most cases. |
| 743 | |
| 744 | config BOOTPARAM_HUNG_TASK_PANIC |
| 745 | bool "Panic (Reboot) On Hung Tasks" |
| 746 | depends on DETECT_HUNG_TASK |
Tim Chen | cca57c5 | 2006-04-18 22:21:47 -0700 | [diff] [blame] | 747 | help |
Ingo Molnar | 408894e | 2006-01-09 15:59:20 -0800 | [diff] [blame] | 748 | Say Y here to enable the kernel to panic on "hung tasks", |
| 749 | which are bugs that cause the kernel to leave a task stuck |
| 750 | in uninterruptible "D" state. |
| 751 | |
| 752 | The panic can be used in combination with panic_timeout, |
Ingo Molnar | e7eebaf | 2006-06-27 02:54:55 -0700 | [diff] [blame] | 753 | to cause the system to reboot automatically after a |
| 754 | hung task has been detected. This feature is useful for |
Ingo Molnar | e7eebaf | 2006-06-27 02:54:55 -0700 | [diff] [blame] | 755 | high-availability systems that have uptime guarantees and |
| 756 | where a hung tasks must be resolved ASAP. |
| 757 | |
| 758 | Say N if unsure. |
| 759 | |
| 760 | config BOOTPARAM_HUNG_TASK_PANIC_VALUE |
| 761 | int |
| 762 | depends on DETECT_HUNG_TASK |
| 763 | range 0 1 |
Hugh Dickins | 048c8bc | 2006-11-01 05:44:54 +1100 | [diff] [blame] | 764 | default 0 if !BOOTPARAM_HUNG_TASK_PANIC |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 765 | default 1 if BOOTPARAM_HUNG_TASK_PANIC |
| 766 | |
Dave Hansen | 92aef8fb | 2013-07-01 13:04:50 -0700 | [diff] [blame] | 767 | endmenu # "Debug lockups and hangs" |
| 768 | |
| 769 | config PANIC_ON_OOPS |
| 770 | bool "Panic on Oops" |
| 771 | help |
| 772 | Say Y here to enable the kernel to panic when it oopses. This |
| 773 | has the same effect as setting oops=panic on the kernel command |
| 774 | line. |
| 775 | |
| 776 | This feature is useful to ensure that the kernel does not do |
| 777 | anything erroneous after an oops which could result in data |
| 778 | corruption or other issues. |
| 779 | |
| 780 | Say N if unsure. |
| 781 | |
| 782 | config PANIC_ON_OOPS_VALUE |
| 783 | int |
| 784 | range 0 1 |
| 785 | default 0 if !PANIC_ON_OOPS |
| 786 | default 1 if PANIC_ON_OOPS |
| 787 | |
Jason Baron | 5800dc3 | 2013-11-25 23:23:04 +0000 | [diff] [blame] | 788 | config PANIC_TIMEOUT |
| 789 | int "panic timeout" |
| 790 | default 0 |
| 791 | help |
| 792 | Set the timeout value (in seconds) until a reboot occurs when the |
| 793 | the kernel panics. If n = 0, then we wait forever. A timeout |
| 794 | value n > 0 will wait n seconds before rebooting, while a timeout |
| 795 | value n < 0 will reboot immediately. |
| 796 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 797 | config SCHED_DEBUG |
| 798 | bool "Collect scheduler debugging info" |
| 799 | depends on DEBUG_KERNEL && PROC_FS |
| 800 | default y |
| 801 | help |
| 802 | If you say Y here, the /proc/sched_debug file will be provided |
| 803 | that can help debug the scheduler. The runtime overhead of this |
| 804 | option is minimal. |
| 805 | |
| 806 | config SCHEDSTATS |
| 807 | bool "Collect scheduler statistics" |
| 808 | depends on DEBUG_KERNEL && PROC_FS |
| 809 | help |
| 810 | If you say Y here, additional code will be inserted into the |
| 811 | scheduler and related routines to collect statistics about |
| 812 | scheduler behavior and provide them in /proc/schedstat. These |
| 813 | stats may be useful for both tuning and debugging the scheduler |
| 814 | If you aren't debugging the scheduler or trying to tune a specific |
| 815 | application, you can say N to avoid the very slight overhead |
| 816 | this adds. |
| 817 | |
Ingo Molnar | e7eebaf | 2006-06-27 02:54:55 -0700 | [diff] [blame] | 818 | config TIMER_STATS |
| 819 | bool "Collect kernel timers statistics" |
| 820 | depends on DEBUG_KERNEL && PROC_FS |
| 821 | help |
| 822 | If you say Y here, additional code will be inserted into the |
| 823 | timer routines to collect statistics about kernel timers being |
| 824 | reprogrammed. The statistics can be read from /proc/timer_stats. |
| 825 | The statistics collection is started by writing 1 to /proc/timer_stats, |
| 826 | writing 0 stops it. This feature is useful to collect information |
| 827 | about timer usage patterns in kernel and userspace. This feature |
| 828 | is lightweight if enabled in the kernel config but not activated |
| 829 | (it defaults to deactivated on bootup and will only be activated |
Ingo Molnar | 4d9f34a | 2006-07-03 00:24:55 -0700 | [diff] [blame] | 830 | if some application like powertop activates it explicitly). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 831 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 832 | config DEBUG_PREEMPT |
| 833 | bool "Debug preemptible kernel" |
Kumar Gala | 01deab9 | 2009-10-16 07:21:39 +0000 | [diff] [blame] | 834 | depends on DEBUG_KERNEL && PREEMPT && TRACE_IRQFLAGS_SUPPORT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 835 | default y |
| 836 | help |
| 837 | If you say Y here then the kernel will use a debug variant of the |
| 838 | commonly used smp_processor_id() function and will print warnings |
| 839 | if kernel code uses it in a preemption-unsafe way. Also, the kernel |
| 840 | will detect preemption count underflows. |
| 841 | |
Dave Hansen | 9eade16 | 2013-07-01 13:04:47 -0700 | [diff] [blame] | 842 | menu "Lock Debugging (spinlocks, mutexes, etc...)" |
| 843 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 844 | config DEBUG_RT_MUTEXES |
| 845 | bool "RT Mutex debugging, deadlock detection" |
| 846 | depends on DEBUG_KERNEL && RT_MUTEXES |
| 847 | help |
| 848 | This allows rt mutex semantics violations and rt mutex related |
| 849 | deadlocks (lockups) to be detected and reported automatically. |
| 850 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 851 | config RT_MUTEX_TESTER |
| 852 | bool "Built-in scriptable tester for rt-mutexes" |
| 853 | depends on DEBUG_KERNEL && RT_MUTEXES |
| 854 | help |
| 855 | This option enables a rt-mutex tester. |
| 856 | |
| 857 | config DEBUG_SPINLOCK |
| 858 | bool "Spinlock and rw-lock debugging: basic checks" |
| 859 | depends on DEBUG_KERNEL |
Raghavendra K T | e335e3e | 2012-03-22 15:25:08 +0530 | [diff] [blame] | 860 | select UNINLINE_SPIN_UNLOCK |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 861 | help |
| 862 | Say Y here and build SMP to catch missing spinlock initialization |
| 863 | and certain other kinds of spinlock errors commonly made. This is |
| 864 | best used in conjunction with the NMI watchdog so that spinlock |
| 865 | deadlocks are also debuggable. |
| 866 | |
Ingo Molnar | 4d9f34a | 2006-07-03 00:24:55 -0700 | [diff] [blame] | 867 | config DEBUG_MUTEXES |
| 868 | bool "Mutex debugging: basic checks" |
| 869 | depends on DEBUG_KERNEL |
| 870 | help |
| 871 | This feature allows mutex semantics violations to be detected and |
| 872 | reported. |
| 873 | |
Daniel Vetter | 2301002 | 2013-06-20 13:31:17 +0200 | [diff] [blame] | 874 | config DEBUG_WW_MUTEX_SLOWPATH |
| 875 | bool "Wait/wound mutex debugging: Slowpath testing" |
| 876 | depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT |
| 877 | select DEBUG_LOCK_ALLOC |
| 878 | select DEBUG_SPINLOCK |
| 879 | select DEBUG_MUTEXES |
| 880 | help |
| 881 | This feature enables slowpath testing for w/w mutex users by |
| 882 | injecting additional -EDEADLK wound/backoff cases. Together with |
| 883 | the full mutex checks enabled with (CONFIG_PROVE_LOCKING) this |
| 884 | will test all possible w/w mutex interface abuse with the |
| 885 | exception of simply not acquiring all the required locks. |
| 886 | |
Ingo Molnar | 4d9f34a | 2006-07-03 00:24:55 -0700 | [diff] [blame] | 887 | config DEBUG_LOCK_ALLOC |
| 888 | bool "Lock debugging: detect incorrect freeing of live locks" |
Adrian Bunk | 517e7aa | 2006-07-14 00:24:32 -0700 | [diff] [blame] | 889 | depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT |
Ingo Molnar | 4d9f34a | 2006-07-03 00:24:55 -0700 | [diff] [blame] | 890 | select DEBUG_SPINLOCK |
| 891 | select DEBUG_MUTEXES |
Ingo Molnar | 4d9f34a | 2006-07-03 00:24:55 -0700 | [diff] [blame] | 892 | select LOCKDEP |
| 893 | help |
| 894 | This feature will check whether any held lock (spinlock, rwlock, |
| 895 | mutex or rwsem) is incorrectly freed by the kernel, via any of the |
| 896 | memory-freeing routines (kfree(), kmem_cache_free(), free_pages(), |
| 897 | vfree(), etc.), whether a live lock is incorrectly reinitialized via |
| 898 | spin_lock_init()/mutex_init()/etc., or whether there is any lock |
| 899 | held during task exit. |
| 900 | |
| 901 | config PROVE_LOCKING |
| 902 | bool "Lock debugging: prove locking correctness" |
Adrian Bunk | 517e7aa | 2006-07-14 00:24:32 -0700 | [diff] [blame] | 903 | depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT |
Ingo Molnar | 4d9f34a | 2006-07-03 00:24:55 -0700 | [diff] [blame] | 904 | select LOCKDEP |
| 905 | select DEBUG_SPINLOCK |
| 906 | select DEBUG_MUTEXES |
Ingo Molnar | 4d9f34a | 2006-07-03 00:24:55 -0700 | [diff] [blame] | 907 | select DEBUG_LOCK_ALLOC |
Steven Rostedt | 46b93b7 | 2010-08-31 16:35:20 -0400 | [diff] [blame] | 908 | select TRACE_IRQFLAGS |
Ingo Molnar | 4d9f34a | 2006-07-03 00:24:55 -0700 | [diff] [blame] | 909 | default n |
| 910 | help |
| 911 | This feature enables the kernel to prove that all locking |
| 912 | that occurs in the kernel runtime is mathematically |
| 913 | correct: that under no circumstance could an arbitrary (and |
| 914 | not yet triggered) combination of observed locking |
| 915 | sequences (on an arbitrary number of CPUs, running an |
| 916 | arbitrary number of tasks and interrupt contexts) cause a |
| 917 | deadlock. |
| 918 | |
| 919 | In short, this feature enables the kernel to report locking |
| 920 | related deadlocks before they actually occur. |
| 921 | |
| 922 | The proof does not depend on how hard and complex a |
| 923 | deadlock scenario would be to trigger: how many |
| 924 | participant CPUs, tasks and irq-contexts would be needed |
| 925 | for it to trigger. The proof also does not depend on |
| 926 | timing: if a race and a resulting deadlock is possible |
| 927 | theoretically (no matter how unlikely the race scenario |
| 928 | is), it will be proven so and will immediately be |
| 929 | reported by the kernel (once the event is observed that |
| 930 | makes the deadlock theoretically possible). |
| 931 | |
| 932 | If a deadlock is impossible (i.e. the locking rules, as |
| 933 | observed by the kernel, are mathematically correct), the |
| 934 | kernel reports nothing. |
| 935 | |
| 936 | NOTE: this feature can also be enabled for rwlocks, mutexes |
| 937 | and rwsems - in which case all dependencies between these |
| 938 | different locking variants are observed and mapped too, and |
| 939 | the proof of observed correctness is also maintained for an |
| 940 | arbitrary combination of these separate locking variants. |
| 941 | |
| 942 | For more details, see Documentation/lockdep-design.txt. |
| 943 | |
| 944 | config LOCKDEP |
| 945 | bool |
Adrian Bunk | 517e7aa | 2006-07-14 00:24:32 -0700 | [diff] [blame] | 946 | depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT |
Ingo Molnar | 4d9f34a | 2006-07-03 00:24:55 -0700 | [diff] [blame] | 947 | select STACKTRACE |
Vineet Gupta | cc80ae3 | 2013-08-27 13:52:51 +0530 | [diff] [blame] | 948 | select FRAME_POINTER if !MIPS && !PPC && !ARM_UNWIND && !S390 && !MICROBLAZE && !ARC |
Ingo Molnar | 4d9f34a | 2006-07-03 00:24:55 -0700 | [diff] [blame] | 949 | select KALLSYMS |
| 950 | select KALLSYMS_ALL |
| 951 | |
Peter Zijlstra | f20786f | 2007-07-19 01:48:56 -0700 | [diff] [blame] | 952 | config LOCK_STAT |
Danny ter Haar | fdfb870 | 2007-09-24 21:24:43 -0700 | [diff] [blame] | 953 | bool "Lock usage statistics" |
Peter Zijlstra | f20786f | 2007-07-19 01:48:56 -0700 | [diff] [blame] | 954 | depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT |
| 955 | select LOCKDEP |
| 956 | select DEBUG_SPINLOCK |
| 957 | select DEBUG_MUTEXES |
| 958 | select DEBUG_LOCK_ALLOC |
| 959 | default n |
| 960 | help |
| 961 | This feature enables tracking lock contention points |
| 962 | |
Peter Zijlstra | a560aa4 | 2007-10-07 00:24:33 -0700 | [diff] [blame] | 963 | For more details, see Documentation/lockstat.txt |
| 964 | |
Frederic Weisbecker | dd8b1cf | 2010-02-27 17:10:39 +0100 | [diff] [blame] | 965 | This also enables lock events required by "perf lock", |
| 966 | subcommand of perf. |
| 967 | If you want to use "perf lock", you also need to turn on |
| 968 | CONFIG_EVENT_TRACING. |
Hitoshi Mitake | 84c6f88 | 2010-02-04 16:08:15 +0900 | [diff] [blame] | 969 | |
| 970 | CONFIG_LOCK_STAT defines "contended" and "acquired" lock events. |
Frederic Weisbecker | dd8b1cf | 2010-02-27 17:10:39 +0100 | [diff] [blame] | 971 | (CONFIG_LOCKDEP defines "acquire" and "release" events.) |
Hitoshi Mitake | 84c6f88 | 2010-02-04 16:08:15 +0900 | [diff] [blame] | 972 | |
Ingo Molnar | 4d9f34a | 2006-07-03 00:24:55 -0700 | [diff] [blame] | 973 | config DEBUG_LOCKDEP |
| 974 | bool "Lock dependency engine debugging" |
Adrian Bunk | 517e7aa | 2006-07-14 00:24:32 -0700 | [diff] [blame] | 975 | depends on DEBUG_KERNEL && LOCKDEP |
Ingo Molnar | 4d9f34a | 2006-07-03 00:24:55 -0700 | [diff] [blame] | 976 | help |
| 977 | If you say Y here, the lock dependency engine will do |
| 978 | additional runtime checks to debug itself, at the price |
| 979 | of more runtime overhead. |
| 980 | |
Frederic Weisbecker | d902db1 | 2011-06-08 19:31:56 +0200 | [diff] [blame] | 981 | config DEBUG_ATOMIC_SLEEP |
| 982 | bool "Sleep inside atomic section checking" |
Frederic Weisbecker | e8f7c70 | 2011-06-08 01:51:02 +0200 | [diff] [blame] | 983 | select PREEMPT_COUNT |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 984 | depends on DEBUG_KERNEL |
| 985 | help |
| 986 | If you say Y here, various routines which may sleep will become very |
Frederic Weisbecker | d902db1 | 2011-06-08 19:31:56 +0200 | [diff] [blame] | 987 | noisy if they are called inside atomic sections: when a spinlock is |
| 988 | held, inside an rcu read side critical section, inside preempt disabled |
| 989 | sections, inside an interrupt, etc... |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 990 | |
Ingo Molnar | cae2ed9 | 2006-07-03 00:24:48 -0700 | [diff] [blame] | 991 | config DEBUG_LOCKING_API_SELFTESTS |
| 992 | bool "Locking API boot-time self-tests" |
| 993 | depends on DEBUG_KERNEL |
| 994 | help |
| 995 | Say Y here if you want the kernel to run a short self-test during |
| 996 | bootup. The self-test checks whether common types of locking bugs |
| 997 | are detected by debugging mechanisms or not. (if you disable |
| 998 | lock debugging then those bugs wont be detected of course.) |
| 999 | The following locking APIs are covered: spinlocks, rwlocks, |
| 1000 | mutexes and rwsems. |
| 1001 | |
Paul E. McKenney | 0af3fe1 | 2014-02-04 15:51:41 -0800 | [diff] [blame] | 1002 | config LOCK_TORTURE_TEST |
| 1003 | tristate "torture tests for locking" |
| 1004 | depends on DEBUG_KERNEL |
| 1005 | select TORTURE_TEST |
| 1006 | default n |
| 1007 | help |
| 1008 | This option provides a kernel module that runs torture tests |
| 1009 | on kernel locking primitives. The kernel module may be built |
| 1010 | after the fact on the running kernel to be tested, if desired. |
| 1011 | |
| 1012 | Say Y here if you want kernel locking-primitive torture tests |
| 1013 | to be built into the kernel. |
| 1014 | Say M if you want these torture tests to build as a module. |
| 1015 | Say N if you are unsure. |
| 1016 | |
Dave Hansen | 9eade16 | 2013-07-01 13:04:47 -0700 | [diff] [blame] | 1017 | endmenu # lock debugging |
| 1018 | |
| 1019 | config TRACE_IRQFLAGS |
| 1020 | bool |
| 1021 | help |
| 1022 | Enables hooks to interrupt enabling and disabling for |
| 1023 | either tracing or lock debugging. |
| 1024 | |
Ingo Molnar | 8637c09 | 2006-07-03 00:24:38 -0700 | [diff] [blame] | 1025 | config STACKTRACE |
| 1026 | bool |
| 1027 | depends on STACKTRACE_SUPPORT |
| 1028 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1029 | config DEBUG_KOBJECT |
| 1030 | bool "kobject debugging" |
| 1031 | depends on DEBUG_KERNEL |
| 1032 | help |
| 1033 | If you say Y here, some extra kobject debugging messages will be sent |
| 1034 | to the syslog. |
| 1035 | |
Russell King | c817a67 | 2013-06-27 15:06:14 +0100 | [diff] [blame] | 1036 | config DEBUG_KOBJECT_RELEASE |
| 1037 | bool "kobject release debugging" |
Linus Torvalds | 2a999aa | 2013-10-29 08:33:36 -0700 | [diff] [blame] | 1038 | depends on DEBUG_OBJECTS_TIMERS |
Russell King | c817a67 | 2013-06-27 15:06:14 +0100 | [diff] [blame] | 1039 | help |
| 1040 | kobjects are reference counted objects. This means that their |
| 1041 | last reference count put is not predictable, and the kobject can |
| 1042 | live on past the point at which a driver decides to drop it's |
| 1043 | initial reference to the kobject gained on allocation. An |
| 1044 | example of this would be a struct device which has just been |
| 1045 | unregistered. |
| 1046 | |
| 1047 | However, some buggy drivers assume that after such an operation, |
| 1048 | the memory backing the kobject can be immediately freed. This |
| 1049 | goes completely against the principles of a refcounted object. |
| 1050 | |
| 1051 | If you say Y here, the kernel will delay the release of kobjects |
| 1052 | on the last reference count to improve the visibility of this |
| 1053 | kind of kobject release bug. |
| 1054 | |
Catalin Marinas | 9b2a60c | 2012-10-08 16:28:13 -0700 | [diff] [blame] | 1055 | config HAVE_DEBUG_BUGVERBOSE |
| 1056 | bool |
| 1057 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1058 | config DEBUG_BUGVERBOSE |
David Rientjes | 6a108a1 | 2011-01-20 14:44:16 -0800 | [diff] [blame] | 1059 | bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT |
Catalin Marinas | 9b2a60c | 2012-10-08 16:28:13 -0700 | [diff] [blame] | 1060 | depends on BUG && (GENERIC_BUG || HAVE_DEBUG_BUGVERBOSE) |
Alexey Dobriyan | 8420e7e | 2009-12-14 18:00:25 -0800 | [diff] [blame] | 1061 | default y |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1062 | help |
| 1063 | Say Y here to make BUG() panics output the file name and line number |
| 1064 | of the BUG call as well as the EIP and oops trace. This aids |
| 1065 | debugging but costs about 70-100K of memory. |
| 1066 | |
Dave Jones | 199a9af | 2006-09-29 01:59:00 -0700 | [diff] [blame] | 1067 | config DEBUG_LIST |
| 1068 | bool "Debug linked list manipulation" |
| 1069 | depends on DEBUG_KERNEL |
| 1070 | help |
| 1071 | Enable this to turn on extended checks in the linked-list |
| 1072 | walking routines. |
| 1073 | |
| 1074 | If unsure, say N. |
| 1075 | |
Dan Streetman | b8cfff6 | 2014-06-04 16:11:54 -0700 | [diff] [blame] | 1076 | config DEBUG_PI_LIST |
| 1077 | bool "Debug priority linked list manipulation" |
| 1078 | depends on DEBUG_KERNEL |
| 1079 | help |
| 1080 | Enable this to turn on extended checks in the priority-ordered |
| 1081 | linked-list (plist) walking routines. This checks the entire |
| 1082 | list multiple times during each manipulation. |
| 1083 | |
| 1084 | If unsure, say N. |
| 1085 | |
Jens Axboe | d6ec084 | 2007-10-22 20:01:06 +0200 | [diff] [blame] | 1086 | config DEBUG_SG |
| 1087 | bool "Debug SG table operations" |
| 1088 | depends on DEBUG_KERNEL |
| 1089 | help |
| 1090 | Enable this to turn on checks on scatter-gather tables. This can |
| 1091 | help find problems with drivers that do not properly initialize |
| 1092 | their sg tables. |
| 1093 | |
| 1094 | If unsure, say N. |
| 1095 | |
Arjan van de Ven | 1b2439d | 2008-08-15 15:29:38 -0700 | [diff] [blame] | 1096 | config DEBUG_NOTIFIERS |
| 1097 | bool "Debug notifier call chains" |
| 1098 | depends on DEBUG_KERNEL |
| 1099 | help |
| 1100 | Enable this to turn on sanity checking for notifier call chains. |
| 1101 | This is most useful for kernel developers to make sure that |
| 1102 | modules properly unregister themselves from notifier chains. |
| 1103 | This is a relatively cheap check but if you care about maximum |
| 1104 | performance, say N. |
| 1105 | |
David Howells | e0e8173 | 2009-09-02 09:13:40 +0100 | [diff] [blame] | 1106 | config DEBUG_CREDENTIALS |
| 1107 | bool "Debug credential management" |
| 1108 | depends on DEBUG_KERNEL |
| 1109 | help |
| 1110 | Enable this to turn on some debug checking for credential |
| 1111 | management. The additional code keeps track of the number of |
| 1112 | pointers from task_structs to any given cred struct, and checks to |
| 1113 | see that this number never exceeds the usage count of the cred |
| 1114 | struct. |
| 1115 | |
| 1116 | Furthermore, if SELinux is enabled, this also checks that the |
| 1117 | security pointer in the cred struct is never seen to be invalid. |
| 1118 | |
| 1119 | If unsure, say N. |
| 1120 | |
Dave Hansen | 2f03e3c | 2013-01-07 08:19:23 -0800 | [diff] [blame] | 1121 | menu "RCU Debugging" |
| 1122 | |
| 1123 | config PROVE_RCU |
| 1124 | bool "RCU debugging: prove RCU correctness" |
| 1125 | depends on PROVE_LOCKING |
| 1126 | default n |
| 1127 | help |
| 1128 | This feature enables lockdep extensions that check for correct |
| 1129 | use of RCU APIs. This is currently under development. Say Y |
| 1130 | if you want to debug RCU usage or help work on the PROVE_RCU |
| 1131 | feature. |
| 1132 | |
| 1133 | Say N if you are unsure. |
| 1134 | |
| 1135 | config PROVE_RCU_REPEATEDLY |
| 1136 | bool "RCU debugging: don't disable PROVE_RCU on first splat" |
| 1137 | depends on PROVE_RCU |
| 1138 | default n |
| 1139 | help |
| 1140 | By itself, PROVE_RCU will disable checking upon issuing the |
| 1141 | first warning (or "splat"). This feature prevents such |
| 1142 | disabling, allowing multiple RCU-lockdep warnings to be printed |
| 1143 | on a single reboot. |
| 1144 | |
| 1145 | Say Y to allow multiple RCU-lockdep warnings per boot. |
| 1146 | |
| 1147 | Say N if you are unsure. |
| 1148 | |
| 1149 | config PROVE_RCU_DELAY |
| 1150 | bool "RCU debugging: preemptible RCU race provocation" |
| 1151 | depends on DEBUG_KERNEL && PREEMPT_RCU |
| 1152 | default n |
| 1153 | help |
| 1154 | There is a class of races that involve an unlikely preemption |
| 1155 | of __rcu_read_unlock() just after ->rcu_read_lock_nesting has |
| 1156 | been set to INT_MIN. This feature inserts a delay at that |
| 1157 | point to increase the probability of these races. |
| 1158 | |
| 1159 | Say Y to increase probability of preemption of __rcu_read_unlock(). |
| 1160 | |
| 1161 | Say N if you are unsure. |
| 1162 | |
| 1163 | config SPARSE_RCU_POINTER |
| 1164 | bool "RCU debugging: sparse-based checks for pointer usage" |
| 1165 | default n |
| 1166 | help |
| 1167 | This feature enables the __rcu sparse annotation for |
| 1168 | RCU-protected pointers. This annotation will cause sparse |
| 1169 | to flag any non-RCU used of annotated pointers. This can be |
| 1170 | helpful when debugging RCU usage. Please note that this feature |
| 1171 | is not intended to enforce code cleanliness; it is instead merely |
| 1172 | a debugging aid. |
| 1173 | |
| 1174 | Say Y to make sparse flag questionable use of RCU-protected pointers |
| 1175 | |
| 1176 | Say N if you are unsure. |
| 1177 | |
Paul E. McKenney | 51b1130 | 2014-01-27 11:49:39 -0800 | [diff] [blame] | 1178 | config TORTURE_TEST |
| 1179 | tristate |
| 1180 | default n |
| 1181 | |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 1182 | config RCU_TORTURE_TEST |
| 1183 | tristate "torture tests for RCU" |
| 1184 | depends on DEBUG_KERNEL |
Paul E. McKenney | 51b1130 | 2014-01-27 11:49:39 -0800 | [diff] [blame] | 1185 | select TORTURE_TEST |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 1186 | default n |
| 1187 | help |
| 1188 | This option provides a kernel module that runs torture tests |
| 1189 | on the RCU infrastructure. The kernel module may be built |
| 1190 | after the fact on the running kernel to be tested, if desired. |
| 1191 | |
Paul E. McKenney | 31a72bc | 2008-06-18 09:26:49 -0700 | [diff] [blame] | 1192 | Say Y here if you want RCU torture tests to be built into |
| 1193 | the kernel. |
Paul E. McKenney | a241ec6 | 2005-10-30 15:03:12 -0800 | [diff] [blame] | 1194 | Say M if you want the RCU torture tests to build as a module. |
| 1195 | Say N if you are unsure. |
Ankita Garg | 8bb31b9 | 2006-10-02 02:17:36 -0700 | [diff] [blame] | 1196 | |
Paul E. McKenney | 31a72bc | 2008-06-18 09:26:49 -0700 | [diff] [blame] | 1197 | config RCU_TORTURE_TEST_RUNNABLE |
| 1198 | bool "torture tests for RCU runnable by default" |
| 1199 | depends on RCU_TORTURE_TEST = y |
| 1200 | default n |
| 1201 | help |
| 1202 | This option provides a way to build the RCU torture tests |
| 1203 | directly into the kernel without them starting up at boot |
| 1204 | time. You can use /proc/sys/kernel/rcutorture_runnable |
| 1205 | to manually override this setting. This /proc file is |
| 1206 | available only when the RCU torture tests have been built |
| 1207 | into the kernel. |
| 1208 | |
| 1209 | Say Y here if you want the RCU torture tests to start during |
| 1210 | boot (you probably don't). |
| 1211 | Say N here if you want the RCU torture tests to start only |
| 1212 | after being manually enabled via /proc. |
| 1213 | |
Paul E. McKenney | b163760 | 2010-06-02 16:21:38 -0700 | [diff] [blame] | 1214 | config RCU_CPU_STALL_TIMEOUT |
| 1215 | int "RCU CPU stall timeout in seconds" |
Paul E. McKenney | 6bfc09e | 2012-10-19 12:49:17 -0700 | [diff] [blame] | 1216 | depends on RCU_STALL_COMMON |
Paul E. McKenney | b163760 | 2010-06-02 16:21:38 -0700 | [diff] [blame] | 1217 | range 3 300 |
Paul E. McKenney | c896054 | 2012-10-25 17:59:23 -0700 | [diff] [blame] | 1218 | default 21 |
Paul E. McKenney | b163760 | 2010-06-02 16:21:38 -0700 | [diff] [blame] | 1219 | help |
| 1220 | If a given RCU grace period extends more than the specified |
| 1221 | number of seconds, a CPU stall warning is printed. If the |
| 1222 | RCU grace period persists, additional CPU stall warnings are |
| 1223 | printed at more widely spaced intervals. |
| 1224 | |
Paul E. McKenney | 1ed509a | 2010-02-22 17:05:05 -0800 | [diff] [blame] | 1225 | config RCU_CPU_STALL_VERBOSE |
| 1226 | bool "Print additional per-task information for RCU_CPU_STALL_DETECTOR" |
Paul E. McKenney | a00e0d71 | 2011-02-08 17:14:39 -0800 | [diff] [blame] | 1227 | depends on TREE_PREEMPT_RCU |
Paul E. McKenney | 55ec936 | 2010-04-13 12:22:33 -0700 | [diff] [blame] | 1228 | default y |
Paul E. McKenney | 1ed509a | 2010-02-22 17:05:05 -0800 | [diff] [blame] | 1229 | help |
| 1230 | This option causes RCU to printk detailed per-task information |
| 1231 | for any tasks that are stalling the current RCU grace period. |
Paul E. McKenney | 64db4cf | 2008-12-18 21:55:32 +0100 | [diff] [blame] | 1232 | |
| 1233 | Say N if you are unsure. |
| 1234 | |
Paul E. McKenney | 1ed509a | 2010-02-22 17:05:05 -0800 | [diff] [blame] | 1235 | Say Y if you want to enable such checks. |
| 1236 | |
Paul E. McKenney | a858af2 | 2012-01-16 13:29:10 -0800 | [diff] [blame] | 1237 | config RCU_CPU_STALL_INFO |
| 1238 | bool "Print additional diagnostics on RCU CPU stall" |
| 1239 | depends on (TREE_RCU || TREE_PREEMPT_RCU) && DEBUG_KERNEL |
| 1240 | default n |
| 1241 | help |
| 1242 | For each stalled CPU that is aware of the current RCU grace |
| 1243 | period, print out additional per-CPU diagnostic information |
| 1244 | regarding scheduling-clock ticks, idle state, and, |
| 1245 | for RCU_FAST_NO_HZ kernels, idle-entry state. |
| 1246 | |
| 1247 | Say N if you are unsure. |
| 1248 | |
| 1249 | Say Y if you want to enable such diagnostics. |
| 1250 | |
Paul E. McKenney | 5c8806a | 2012-01-06 15:10:44 -0800 | [diff] [blame] | 1251 | config RCU_TRACE |
| 1252 | bool "Enable tracing for RCU" |
| 1253 | depends on DEBUG_KERNEL |
Paul E. McKenney | 5249453 | 2012-11-14 16:26:40 -0800 | [diff] [blame] | 1254 | select TRACE_CLOCK |
Paul E. McKenney | 5c8806a | 2012-01-06 15:10:44 -0800 | [diff] [blame] | 1255 | help |
| 1256 | This option provides tracing in RCU which presents stats |
| 1257 | in debugfs for debugging RCU implementation. |
| 1258 | |
| 1259 | Say Y here if you want to enable RCU tracing |
| 1260 | Say N if you are unsure. |
| 1261 | |
Dave Hansen | 2f03e3c | 2013-01-07 08:19:23 -0800 | [diff] [blame] | 1262 | endmenu # "RCU Debugging" |
| 1263 | |
Tejun Heo | 870d665 | 2008-08-25 19:47:25 +0900 | [diff] [blame] | 1264 | config DEBUG_BLOCK_EXT_DEVT |
| 1265 | bool "Force extended block device numbers and spread them" |
| 1266 | depends on DEBUG_KERNEL |
| 1267 | depends on BLOCK |
Jens Axboe | 759f8ca | 2008-08-29 09:06:29 +0200 | [diff] [blame] | 1268 | default n |
Tejun Heo | 870d665 | 2008-08-25 19:47:25 +0900 | [diff] [blame] | 1269 | help |
Tejun Heo | 0e11e34 | 2008-10-13 10:46:01 +0200 | [diff] [blame] | 1270 | BIG FAT WARNING: ENABLING THIS OPTION MIGHT BREAK BOOTING ON |
| 1271 | SOME DISTRIBUTIONS. DO NOT ENABLE THIS UNLESS YOU KNOW WHAT |
| 1272 | YOU ARE DOING. Distros, please enable this and fix whatever |
| 1273 | is broken. |
| 1274 | |
Tejun Heo | 870d665 | 2008-08-25 19:47:25 +0900 | [diff] [blame] | 1275 | Conventionally, block device numbers are allocated from |
| 1276 | predetermined contiguous area. However, extended block area |
| 1277 | may introduce non-contiguous block device numbers. This |
| 1278 | option forces most block device numbers to be allocated from |
| 1279 | the extended space and spreads them to discover kernel or |
| 1280 | userland code paths which assume predetermined contiguous |
| 1281 | device number allocation. |
| 1282 | |
Tejun Heo | 55dc7db | 2008-09-01 13:44:35 +0200 | [diff] [blame] | 1283 | Note that turning on this debug option shuffles all the |
| 1284 | device numbers for all IDE and SCSI devices including libata |
| 1285 | ones, so root partition specified using device number |
| 1286 | directly (via rdev or root=MAJ:MIN) won't work anymore. |
| 1287 | Textual device names (root=/dev/sdXn) will continue to work. |
| 1288 | |
Tejun Heo | 870d665 | 2008-08-25 19:47:25 +0900 | [diff] [blame] | 1289 | Say N if you are unsure. |
| 1290 | |
Akinobu Mita | 8d43828 | 2012-07-30 14:43:02 -0700 | [diff] [blame] | 1291 | config NOTIFIER_ERROR_INJECTION |
| 1292 | tristate "Notifier error injection" |
| 1293 | depends on DEBUG_KERNEL |
| 1294 | select DEBUG_FS |
| 1295 | help |
Masanari Iida | e41e85c | 2012-11-30 16:44:39 +0900 | [diff] [blame] | 1296 | This option provides the ability to inject artificial errors to |
Akinobu Mita | 8d43828 | 2012-07-30 14:43:02 -0700 | [diff] [blame] | 1297 | specified notifier chain callbacks. It is useful to test the error |
| 1298 | handling of notifier call chain failures. |
| 1299 | |
| 1300 | Say N if unsure. |
| 1301 | |
Akinobu Mita | c9d221f | 2010-05-26 14:43:36 -0700 | [diff] [blame] | 1302 | config CPU_NOTIFIER_ERROR_INJECT |
| 1303 | tristate "CPU notifier error injection module" |
Akinobu Mita | f5a9f52 | 2012-07-30 14:43:03 -0700 | [diff] [blame] | 1304 | depends on HOTPLUG_CPU && NOTIFIER_ERROR_INJECTION |
Akinobu Mita | c9d221f | 2010-05-26 14:43:36 -0700 | [diff] [blame] | 1305 | help |
| 1306 | This option provides a kernel module that can be used to test |
Masanari Iida | e41e85c | 2012-11-30 16:44:39 +0900 | [diff] [blame] | 1307 | the error handling of the cpu notifiers by injecting artificial |
Akinobu Mita | f5a9f52 | 2012-07-30 14:43:03 -0700 | [diff] [blame] | 1308 | errors to CPU notifier chain callbacks. It is controlled through |
| 1309 | debugfs interface under /sys/kernel/debug/notifier-error-inject/cpu |
| 1310 | |
| 1311 | If the notifier call chain should be failed with some events |
| 1312 | notified, write the error code to "actions/<notifier event>/error". |
| 1313 | |
| 1314 | Example: Inject CPU offline error (-1 == -EPERM) |
| 1315 | |
| 1316 | # cd /sys/kernel/debug/notifier-error-inject/cpu |
| 1317 | # echo -1 > actions/CPU_DOWN_PREPARE/error |
| 1318 | # echo 0 > /sys/devices/system/cpu/cpu1/online |
| 1319 | bash: echo: write error: Operation not permitted |
Akinobu Mita | c9d221f | 2010-05-26 14:43:36 -0700 | [diff] [blame] | 1320 | |
| 1321 | To compile this code as a module, choose M here: the module will |
| 1322 | be called cpu-notifier-error-inject. |
| 1323 | |
| 1324 | If unsure, say N. |
| 1325 | |
Akinobu Mita | 048b9c35 | 2012-07-30 14:43:07 -0700 | [diff] [blame] | 1326 | config PM_NOTIFIER_ERROR_INJECT |
| 1327 | tristate "PM notifier error injection module" |
| 1328 | depends on PM && NOTIFIER_ERROR_INJECTION |
| 1329 | default m if PM_DEBUG |
| 1330 | help |
Masanari Iida | e41e85c | 2012-11-30 16:44:39 +0900 | [diff] [blame] | 1331 | This option provides the ability to inject artificial errors to |
Akinobu Mita | 048b9c35 | 2012-07-30 14:43:07 -0700 | [diff] [blame] | 1332 | PM notifier chain callbacks. It is controlled through debugfs |
| 1333 | interface /sys/kernel/debug/notifier-error-inject/pm |
| 1334 | |
| 1335 | If the notifier call chain should be failed with some events |
| 1336 | notified, write the error code to "actions/<notifier event>/error". |
| 1337 | |
| 1338 | Example: Inject PM suspend error (-12 = -ENOMEM) |
| 1339 | |
| 1340 | # cd /sys/kernel/debug/notifier-error-inject/pm/ |
| 1341 | # echo -12 > actions/PM_SUSPEND_PREPARE/error |
| 1342 | # echo mem > /sys/power/state |
| 1343 | bash: echo: write error: Cannot allocate memory |
| 1344 | |
| 1345 | To compile this code as a module, choose M here: the module will |
| 1346 | be called pm-notifier-error-inject. |
| 1347 | |
| 1348 | If unsure, say N. |
| 1349 | |
Benjamin Herrenschmidt | d526e85 | 2012-12-14 10:32:52 +1100 | [diff] [blame] | 1350 | config OF_RECONFIG_NOTIFIER_ERROR_INJECT |
| 1351 | tristate "OF reconfig notifier error injection module" |
| 1352 | depends on OF_DYNAMIC && NOTIFIER_ERROR_INJECTION |
Akinobu Mita | 08dfb4d | 2012-07-30 14:43:13 -0700 | [diff] [blame] | 1353 | help |
Masanari Iida | e41e85c | 2012-11-30 16:44:39 +0900 | [diff] [blame] | 1354 | This option provides the ability to inject artificial errors to |
Benjamin Herrenschmidt | d526e85 | 2012-12-14 10:32:52 +1100 | [diff] [blame] | 1355 | OF reconfig notifier chain callbacks. It is controlled |
Akinobu Mita | 08dfb4d | 2012-07-30 14:43:13 -0700 | [diff] [blame] | 1356 | through debugfs interface under |
Benjamin Herrenschmidt | d526e85 | 2012-12-14 10:32:52 +1100 | [diff] [blame] | 1357 | /sys/kernel/debug/notifier-error-inject/OF-reconfig/ |
Akinobu Mita | 08dfb4d | 2012-07-30 14:43:13 -0700 | [diff] [blame] | 1358 | |
| 1359 | If the notifier call chain should be failed with some events |
| 1360 | notified, write the error code to "actions/<notifier event>/error". |
| 1361 | |
| 1362 | To compile this code as a module, choose M here: the module will |
Akinobu Mita | e12a95f | 2013-04-30 15:28:49 -0700 | [diff] [blame] | 1363 | be called of-reconfig-notifier-error-inject. |
Akinobu Mita | 08dfb4d | 2012-07-30 14:43:13 -0700 | [diff] [blame] | 1364 | |
| 1365 | If unsure, say N. |
| 1366 | |
Akinobu Mita | 6ff1cb3 | 2006-12-08 02:39:43 -0800 | [diff] [blame] | 1367 | config FAULT_INJECTION |
Andrew Morton | 1ab8509a | 2006-12-08 02:39:49 -0800 | [diff] [blame] | 1368 | bool "Fault-injection framework" |
| 1369 | depends on DEBUG_KERNEL |
Akinobu Mita | 329409a | 2006-12-08 02:39:48 -0800 | [diff] [blame] | 1370 | help |
| 1371 | Provide fault-injection framework. |
| 1372 | For more details, see Documentation/fault-injection/. |
Akinobu Mita | 6ff1cb3 | 2006-12-08 02:39:43 -0800 | [diff] [blame] | 1373 | |
Akinobu Mita | 8a8b650 | 2006-12-08 02:39:44 -0800 | [diff] [blame] | 1374 | config FAILSLAB |
Andrew Morton | 1ab8509a | 2006-12-08 02:39:49 -0800 | [diff] [blame] | 1375 | bool "Fault-injection capability for kmalloc" |
| 1376 | depends on FAULT_INJECTION |
Akinobu Mita | 773ff60 | 2008-12-23 19:37:01 +0900 | [diff] [blame] | 1377 | depends on SLAB || SLUB |
Akinobu Mita | 8a8b650 | 2006-12-08 02:39:44 -0800 | [diff] [blame] | 1378 | help |
Andrew Morton | 1ab8509a | 2006-12-08 02:39:49 -0800 | [diff] [blame] | 1379 | Provide fault-injection capability for kmalloc. |
Akinobu Mita | 8a8b650 | 2006-12-08 02:39:44 -0800 | [diff] [blame] | 1380 | |
Akinobu Mita | 933e312 | 2006-12-08 02:39:45 -0800 | [diff] [blame] | 1381 | config FAIL_PAGE_ALLOC |
| 1382 | bool "Fault-injection capabilitiy for alloc_pages()" |
Andrew Morton | 1ab8509a | 2006-12-08 02:39:49 -0800 | [diff] [blame] | 1383 | depends on FAULT_INJECTION |
Akinobu Mita | 933e312 | 2006-12-08 02:39:45 -0800 | [diff] [blame] | 1384 | help |
Andrew Morton | 1ab8509a | 2006-12-08 02:39:49 -0800 | [diff] [blame] | 1385 | Provide fault-injection capability for alloc_pages(). |
Akinobu Mita | 933e312 | 2006-12-08 02:39:45 -0800 | [diff] [blame] | 1386 | |
Akinobu Mita | c17bb49 | 2006-12-08 02:39:46 -0800 | [diff] [blame] | 1387 | config FAIL_MAKE_REQUEST |
Dave Jones | 86327d1 | 2006-12-12 20:16:36 +0100 | [diff] [blame] | 1388 | bool "Fault-injection capability for disk IO" |
Jens Axboe | 581d4e2 | 2008-09-14 05:56:33 -0700 | [diff] [blame] | 1389 | depends on FAULT_INJECTION && BLOCK |
Akinobu Mita | c17bb49 | 2006-12-08 02:39:46 -0800 | [diff] [blame] | 1390 | help |
Andrew Morton | 1ab8509a | 2006-12-08 02:39:49 -0800 | [diff] [blame] | 1391 | Provide fault-injection capability for disk IO. |
Akinobu Mita | c17bb49 | 2006-12-08 02:39:46 -0800 | [diff] [blame] | 1392 | |
Jens Axboe | 581d4e2 | 2008-09-14 05:56:33 -0700 | [diff] [blame] | 1393 | config FAIL_IO_TIMEOUT |
Takuya Yoshikawa | f4d0143 | 2010-07-21 16:05:53 +0900 | [diff] [blame] | 1394 | bool "Fault-injection capability for faking disk interrupts" |
Jens Axboe | 581d4e2 | 2008-09-14 05:56:33 -0700 | [diff] [blame] | 1395 | depends on FAULT_INJECTION && BLOCK |
| 1396 | help |
| 1397 | Provide fault-injection capability on end IO handling. This |
| 1398 | will make the block layer "forget" an interrupt as configured, |
| 1399 | thus exercising the error handling. |
| 1400 | |
| 1401 | Only works with drivers that use the generic timeout handling, |
| 1402 | for others it wont do anything. |
| 1403 | |
Per Forlin | 1b676f7 | 2011-08-19 14:52:37 +0200 | [diff] [blame] | 1404 | config FAIL_MMC_REQUEST |
| 1405 | bool "Fault-injection capability for MMC IO" |
| 1406 | select DEBUG_FS |
| 1407 | depends on FAULT_INJECTION && MMC |
| 1408 | help |
| 1409 | Provide fault-injection capability for MMC IO. |
| 1410 | This will make the mmc core return data errors. This is |
| 1411 | useful to test the error handling in the mmc block device |
| 1412 | and to test how the mmc host driver handles retries from |
| 1413 | the block device. |
| 1414 | |
Akinobu Mita | 6ff1cb3 | 2006-12-08 02:39:43 -0800 | [diff] [blame] | 1415 | config FAULT_INJECTION_DEBUG_FS |
| 1416 | bool "Debugfs entries for fault-injection capabilities" |
Andrew Morton | 1ab8509a | 2006-12-08 02:39:49 -0800 | [diff] [blame] | 1417 | depends on FAULT_INJECTION && SYSFS && DEBUG_FS |
Akinobu Mita | 6ff1cb3 | 2006-12-08 02:39:43 -0800 | [diff] [blame] | 1418 | help |
Andrew Morton | 1ab8509a | 2006-12-08 02:39:49 -0800 | [diff] [blame] | 1419 | Enable configuration of fault-injection capabilities via debugfs. |
Akinobu Mita | 1df4900 | 2007-02-20 13:57:56 -0800 | [diff] [blame] | 1420 | |
| 1421 | config FAULT_INJECTION_STACKTRACE_FILTER |
| 1422 | bool "stacktrace filter for fault-injection capabilities" |
| 1423 | depends on FAULT_INJECTION_DEBUG_FS && STACKTRACE_SUPPORT |
Akinobu Mita | 6d690dc | 2007-05-12 10:36:53 -0700 | [diff] [blame] | 1424 | depends on !X86_64 |
Akinobu Mita | 1df4900 | 2007-02-20 13:57:56 -0800 | [diff] [blame] | 1425 | select STACKTRACE |
Vineet Gupta | cc80ae3 | 2013-08-27 13:52:51 +0530 | [diff] [blame] | 1426 | select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND && !ARC |
Akinobu Mita | 1df4900 | 2007-02-20 13:57:56 -0800 | [diff] [blame] | 1427 | help |
| 1428 | Provide stacktrace filter for fault-injection capabilities |
Mathieu Desnoyers | 267c402 | 2007-10-18 23:41:07 -0700 | [diff] [blame] | 1429 | |
Arjan van de Ven | 9745512 | 2008-01-25 21:08:34 +0100 | [diff] [blame] | 1430 | config LATENCYTOP |
| 1431 | bool "Latency measuring infrastructure" |
Randy Dunlap | 625fdca | 2010-08-12 12:31:21 -0700 | [diff] [blame] | 1432 | depends on HAVE_LATENCYTOP_SUPPORT |
| 1433 | depends on DEBUG_KERNEL |
| 1434 | depends on STACKTRACE_SUPPORT |
| 1435 | depends on PROC_FS |
Vineet Gupta | cc80ae3 | 2013-08-27 13:52:51 +0530 | [diff] [blame] | 1436 | select FRAME_POINTER if !MIPS && !PPC && !S390 && !MICROBLAZE && !ARM_UNWIND && !ARC |
Arjan van de Ven | 9745512 | 2008-01-25 21:08:34 +0100 | [diff] [blame] | 1437 | select KALLSYMS |
| 1438 | select KALLSYMS_ALL |
| 1439 | select STACKTRACE |
| 1440 | select SCHEDSTATS |
| 1441 | select SCHED_DEBUG |
Arjan van de Ven | 9745512 | 2008-01-25 21:08:34 +0100 | [diff] [blame] | 1442 | help |
| 1443 | Enable this option if you want to use the LatencyTOP tool |
| 1444 | to find out which userspace is blocking on what kernel operations. |
| 1445 | |
Stephen Boyd | 446f24d | 2013-04-30 15:28:42 -0700 | [diff] [blame] | 1446 | config ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS |
| 1447 | bool |
| 1448 | |
| 1449 | config DEBUG_STRICT_USER_COPY_CHECKS |
| 1450 | bool "Strict user copy size checks" |
| 1451 | depends on ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS |
| 1452 | depends on DEBUG_KERNEL && !TRACE_BRANCH_PROFILING |
| 1453 | help |
| 1454 | Enabling this option turns a certain set of sanity checks for user |
| 1455 | copy operations into compile time failures. |
| 1456 | |
| 1457 | The copy_from_user() etc checks are there to help test if there |
| 1458 | are sufficient security checks on the length argument of |
| 1459 | the copy operation, by having gcc prove that the argument is |
| 1460 | within bounds. |
| 1461 | |
| 1462 | If unsure, say N. |
| 1463 | |
Arnaldo Carvalho de Melo | 16444a8 | 2008-05-12 21:20:42 +0200 | [diff] [blame] | 1464 | source kernel/trace/Kconfig |
| 1465 | |
Dave Hansen | 881c514 | 2013-07-01 13:04:44 -0700 | [diff] [blame] | 1466 | menu "Runtime Testing" |
| 1467 | |
| 1468 | config LKDTM |
| 1469 | tristate "Linux Kernel Dump Test Tool Module" |
| 1470 | depends on DEBUG_FS |
| 1471 | depends on BLOCK |
| 1472 | default n |
| 1473 | help |
| 1474 | This module enables testing of the different dumping mechanisms by |
| 1475 | inducing system failures at predefined crash points. |
| 1476 | If you don't need it: say N |
| 1477 | Choose M here to compile this code as a module. The module will be |
| 1478 | called lkdtm. |
| 1479 | |
| 1480 | Documentation on how to use the module can be found in |
| 1481 | Documentation/fault-injection/provoke-crashes.txt |
| 1482 | |
| 1483 | config TEST_LIST_SORT |
| 1484 | bool "Linked list sorting test" |
| 1485 | depends on DEBUG_KERNEL |
| 1486 | help |
| 1487 | Enable this to turn on 'list_sort()' function test. This test is |
| 1488 | executed only once during system boot, so affects only boot time. |
| 1489 | |
| 1490 | If unsure, say N. |
| 1491 | |
| 1492 | config KPROBES_SANITY_TEST |
| 1493 | bool "Kprobes sanity tests" |
| 1494 | depends on DEBUG_KERNEL |
| 1495 | depends on KPROBES |
| 1496 | default n |
| 1497 | help |
| 1498 | This option provides for testing basic kprobes functionality on |
| 1499 | boot. A sample kprobe, jprobe and kretprobe are inserted and |
| 1500 | verified for functionality. |
| 1501 | |
| 1502 | Say N if you are unsure. |
| 1503 | |
| 1504 | config BACKTRACE_SELF_TEST |
| 1505 | tristate "Self test for the backtrace code" |
| 1506 | depends on DEBUG_KERNEL |
| 1507 | default n |
| 1508 | help |
| 1509 | This option provides a kernel module that can be used to test |
| 1510 | the kernel stack backtrace code. This option is not useful |
| 1511 | for distributions or general kernels, but only for kernel |
| 1512 | developers working on architecture code. |
| 1513 | |
| 1514 | Note that if you want to also test saved backtraces, you will |
| 1515 | have to enable STACKTRACE as well. |
| 1516 | |
| 1517 | Say N if you are unsure. |
| 1518 | |
Michel Lespinasse | 910a742 | 2012-10-08 16:30:39 -0700 | [diff] [blame] | 1519 | config RBTREE_TEST |
| 1520 | tristate "Red-Black tree test" |
Cody P Schafer | 7c993e1 | 2013-09-11 14:25:19 -0700 | [diff] [blame] | 1521 | depends on DEBUG_KERNEL |
Michel Lespinasse | 910a742 | 2012-10-08 16:30:39 -0700 | [diff] [blame] | 1522 | help |
| 1523 | A benchmark measuring the performance of the rbtree library. |
| 1524 | Also includes rbtree invariant checks. |
| 1525 | |
Michel Lespinasse | fff3fd8 | 2012-10-08 16:31:23 -0700 | [diff] [blame] | 1526 | config INTERVAL_TREE_TEST |
| 1527 | tristate "Interval tree test" |
| 1528 | depends on m && DEBUG_KERNEL |
Chris Wilson | a88cc10 | 2014-03-17 12:21:54 +0000 | [diff] [blame] | 1529 | select INTERVAL_TREE |
Michel Lespinasse | fff3fd8 | 2012-10-08 16:31:23 -0700 | [diff] [blame] | 1530 | help |
| 1531 | A benchmark measuring the performance of the interval tree library |
| 1532 | |
Greg Thelen | 623fd80 | 2013-11-12 15:08:34 -0800 | [diff] [blame] | 1533 | config PERCPU_TEST |
| 1534 | tristate "Per cpu operations test" |
| 1535 | depends on m && DEBUG_KERNEL |
| 1536 | help |
| 1537 | Enable this option to build test module which validates per-cpu |
| 1538 | operations. |
| 1539 | |
| 1540 | If unsure, say N. |
| 1541 | |
Dave Hansen | 881c514 | 2013-07-01 13:04:44 -0700 | [diff] [blame] | 1542 | config ATOMIC64_SELFTEST |
| 1543 | bool "Perform an atomic64_t self-test at boot" |
| 1544 | help |
| 1545 | Enable this option to test the atomic64_t functions at boot. |
| 1546 | |
| 1547 | If unsure, say N. |
| 1548 | |
| 1549 | config ASYNC_RAID6_TEST |
| 1550 | tristate "Self test for hardware accelerated raid6 recovery" |
| 1551 | depends on ASYNC_RAID6_RECOV |
| 1552 | select ASYNC_MEMCPY |
| 1553 | ---help--- |
| 1554 | This is a one-shot self test that permutes through the |
| 1555 | recovery of all the possible two disk failure scenarios for a |
| 1556 | N-disk array. Recovery is performed with the asynchronous |
| 1557 | raid6 recovery routines, and will optionally use an offload |
| 1558 | engine if one is available. |
| 1559 | |
| 1560 | If unsure, say N. |
| 1561 | |
| 1562 | config TEST_STRING_HELPERS |
| 1563 | tristate "Test functions located in the string_helpers module at runtime" |
| 1564 | |
| 1565 | config TEST_KSTRTOX |
| 1566 | tristate "Test kstrto*() family of functions at runtime" |
| 1567 | |
| 1568 | endmenu # runtime tests |
| 1569 | |
Bernhard Kaindl | f212ec4 | 2008-01-30 13:34:11 +0100 | [diff] [blame] | 1570 | config PROVIDE_OHCI1394_DMA_INIT |
Stefan Richter | 080de8c | 2008-02-28 20:54:43 +0100 | [diff] [blame] | 1571 | bool "Remote debugging over FireWire early on boot" |
Bernhard Kaindl | f212ec4 | 2008-01-30 13:34:11 +0100 | [diff] [blame] | 1572 | depends on PCI && X86 |
| 1573 | help |
| 1574 | If you want to debug problems which hang or crash the kernel early |
| 1575 | on boot and the crashing machine has a FireWire port, you can use |
| 1576 | this feature to remotely access the memory of the crashed machine |
| 1577 | over FireWire. This employs remote DMA as part of the OHCI1394 |
| 1578 | specification which is now the standard for FireWire controllers. |
| 1579 | |
| 1580 | With remote DMA, you can monitor the printk buffer remotely using |
| 1581 | firescope and access all memory below 4GB using fireproxy from gdb. |
| 1582 | Even controlling a kernel debugger is possible using remote DMA. |
| 1583 | |
| 1584 | Usage: |
| 1585 | |
| 1586 | If ohci1394_dma=early is used as boot parameter, it will initialize |
| 1587 | all OHCI1394 controllers which are found in the PCI config space. |
| 1588 | |
| 1589 | As all changes to the FireWire bus such as enabling and disabling |
| 1590 | devices cause a bus reset and thereby disable remote DMA for all |
| 1591 | devices, be sure to have the cable plugged and FireWire enabled on |
| 1592 | the debugging host before booting the debug target for debugging. |
| 1593 | |
| 1594 | This code (~1k) is freed after boot. By then, the firewire stack |
| 1595 | in charge of the OHCI-1394 controllers should be used instead. |
| 1596 | |
| 1597 | See Documentation/debugging-via-ohci1394.txt for more information. |
Arjan van de Ven | 9745512 | 2008-01-25 21:08:34 +0100 | [diff] [blame] | 1598 | |
Randy Dunlap | 152de30 | 2009-02-20 15:38:47 -0800 | [diff] [blame] | 1599 | config BUILD_DOCSRC |
Randy Dunlap | 3794f3e | 2008-08-12 15:09:06 -0700 | [diff] [blame] | 1600 | bool "Build targets in Documentation/ tree" |
| 1601 | depends on HEADERS_CHECK |
| 1602 | help |
| 1603 | This option attempts to build objects from the source files in the |
| 1604 | kernel Documentation/ tree. |
| 1605 | |
| 1606 | Say N if you are unsure. |
| 1607 | |
Joerg Roedel | 5ee00bd | 2009-01-09 12:14:24 +0100 | [diff] [blame] | 1608 | config DMA_API_DEBUG |
| 1609 | bool "Enable debugging of DMA-API usage" |
| 1610 | depends on HAVE_DMA_API_DEBUG |
| 1611 | help |
| 1612 | Enable this option to debug the use of the DMA API by device drivers. |
| 1613 | With this option you will be able to detect common bugs in device |
| 1614 | drivers like double-freeing of DMA mappings or freeing mappings that |
| 1615 | were never allocated. |
Dan Williams | 0abdd7a | 2014-01-21 15:48:12 -0800 | [diff] [blame] | 1616 | |
| 1617 | This also attempts to catch cases where a page owned by DMA is |
| 1618 | accessed by the cpu in a way that could cause data corruption. For |
| 1619 | example, this enables cow_user_page() to check that the source page is |
| 1620 | not undergoing DMA. |
| 1621 | |
| 1622 | This option causes a performance degradation. Use only if you want to |
| 1623 | debug device drivers and dma interactions. |
| 1624 | |
| 1625 | If unsure, say N. |
Jason Baron | 346e15b | 2008-08-12 16:46:19 -0400 | [diff] [blame] | 1626 | |
Kees Cook | 93e9ef8 | 2014-01-23 15:54:37 -0800 | [diff] [blame] | 1627 | config TEST_MODULE |
| 1628 | tristate "Test module loading with 'hello world' module" |
| 1629 | default n |
| 1630 | depends on m |
| 1631 | help |
| 1632 | This builds the "test_module" module that emits "Hello, world" |
| 1633 | on printk when loaded. It is designed to be used for basic |
| 1634 | evaluation of the module loading subsystem (for example when |
| 1635 | validating module verification). It lacks any extra dependencies, |
| 1636 | and will not normally be loaded by the system unless explicitly |
| 1637 | requested by name. |
| 1638 | |
| 1639 | If unsure, say N. |
| 1640 | |
Kees Cook | 3e2a4c1 | 2014-01-23 15:54:38 -0800 | [diff] [blame] | 1641 | config TEST_USER_COPY |
| 1642 | tristate "Test user/kernel boundary protections" |
| 1643 | default n |
| 1644 | depends on m |
| 1645 | help |
| 1646 | This builds the "test_user_copy" module that runs sanity checks |
| 1647 | on the copy_to/from_user infrastructure, making sure basic |
| 1648 | user/kernel boundary testing is working. If it fails to load, |
| 1649 | a regression has been detected in the user/kernel memory boundary |
| 1650 | protections. |
| 1651 | |
| 1652 | If unsure, say N. |
| 1653 | |
Alexei Starovoitov | 64a8946 | 2014-05-08 14:10:52 -0700 | [diff] [blame] | 1654 | config TEST_BPF |
| 1655 | tristate "Test BPF filter functionality" |
| 1656 | default n |
Randy Dunlap | 98920ba | 2014-05-13 09:58:44 -0700 | [diff] [blame] | 1657 | depends on m && NET |
Alexei Starovoitov | 64a8946 | 2014-05-08 14:10:52 -0700 | [diff] [blame] | 1658 | help |
| 1659 | This builds the "test_bpf" module that runs various test vectors |
| 1660 | against the BPF interpreter or BPF JIT compiler depending on the |
| 1661 | current setting. This is in particular useful for BPF JIT compiler |
| 1662 | development, but also to run regression tests against changes in |
| 1663 | the interpreter code. |
| 1664 | |
| 1665 | If unsure, say N. |
| 1666 | |
Mathieu Desnoyers | 267c402 | 2007-10-18 23:41:07 -0700 | [diff] [blame] | 1667 | source "samples/Kconfig" |
Jason Wessel | dc7d552 | 2008-04-17 20:05:37 +0200 | [diff] [blame] | 1668 | |
| 1669 | source "lib/Kconfig.kgdb" |
Pekka Enberg | 0a4af3b | 2009-02-26 21:38:56 +0200 | [diff] [blame] | 1670 | |