1 # SPDX-License-Identifier: GPL-2.0-only 1 # SPDX-License-Identifier: GPL-2.0-only 2 menu "Kernel hacking" 2 menu "Kernel hacking" 3 3 4 menu "printk and dmesg options" 4 menu "printk and dmesg options" 5 5 6 config PRINTK_TIME 6 config PRINTK_TIME 7 bool "Show timing information on print 7 bool "Show timing information on printks" 8 depends on PRINTK 8 depends on PRINTK 9 help 9 help 10 Selecting this option causes time st 10 Selecting this option causes time stamps of the printk() 11 messages to be added to the output o 11 messages to be added to the output of the syslog() system 12 call and at the console. 12 call and at the console. 13 13 14 The timestamp is always recorded int 14 The timestamp is always recorded internally, and exported 15 to /dev/kmsg. This flag just specifi 15 to /dev/kmsg. This flag just specifies if the timestamp should 16 be included, not that the timestamp 16 be included, not that the timestamp is recorded. 17 17 18 The behavior is also controlled by t 18 The behavior is also controlled by the kernel command line 19 parameter printk.time=1. See Documen 19 parameter printk.time=1. See Documentation/admin-guide/kernel-parameters.rst 20 20 21 config PRINTK_CALLER 21 config PRINTK_CALLER 22 bool "Show caller information on print 22 bool "Show caller information on printks" 23 depends on PRINTK 23 depends on PRINTK 24 help 24 help 25 Selecting this option causes printk( 25 Selecting this option causes printk() to add a caller "thread id" (if 26 in task context) or a caller "proces 26 in task context) or a caller "processor id" (if not in task context) 27 to every message. 27 to every message. 28 28 29 This option is intended for environm 29 This option is intended for environments where multiple threads 30 concurrently call printk() for many 30 concurrently call printk() for many times, for it is difficult to 31 interpret without knowing where thes 31 interpret without knowing where these lines (or sometimes individual 32 line which was divided into multiple 32 line which was divided into multiple lines due to race) came from. 33 33 34 Since toggling after boot makes the 34 Since toggling after boot makes the code racy, currently there is 35 no option to enable/disable at the k 35 no option to enable/disable at the kernel command line parameter or 36 sysfs interface. 36 sysfs interface. 37 37 38 config STACKTRACE_BUILD_ID 38 config STACKTRACE_BUILD_ID 39 bool "Show build ID information in sta 39 bool "Show build ID information in stacktraces" 40 depends on PRINTK 40 depends on PRINTK 41 help 41 help 42 Selecting this option adds build ID 42 Selecting this option adds build ID information for symbols in 43 stacktraces printed with the printk 43 stacktraces printed with the printk format '%p[SR]b'. 44 44 45 This option is intended for distros 45 This option is intended for distros where debuginfo is not easily 46 accessible but can be downloaded giv 46 accessible but can be downloaded given the build ID of the vmlinux or 47 kernel module where the function is 47 kernel module where the function is located. 48 48 49 config CONSOLE_LOGLEVEL_DEFAULT 49 config CONSOLE_LOGLEVEL_DEFAULT 50 int "Default console loglevel (1-15)" 50 int "Default console loglevel (1-15)" 51 range 1 15 51 range 1 15 52 default "7" 52 default "7" 53 help 53 help 54 Default loglevel to determine what w 54 Default loglevel to determine what will be printed on the console. 55 55 56 Setting a default here is equivalent 56 Setting a default here is equivalent to passing in loglevel=<x> in 57 the kernel bootargs. loglevel=<x> co 57 the kernel bootargs. loglevel=<x> continues to override whatever 58 value is specified here as well. 58 value is specified here as well. 59 59 60 Note: This does not affect the log l 60 Note: This does not affect the log level of un-prefixed printk() 61 usage in the kernel. That is control 61 usage in the kernel. That is controlled by the MESSAGE_LOGLEVEL_DEFAULT 62 option. 62 option. 63 63 64 config CONSOLE_LOGLEVEL_QUIET 64 config CONSOLE_LOGLEVEL_QUIET 65 int "quiet console loglevel (1-15)" 65 int "quiet console loglevel (1-15)" 66 range 1 15 66 range 1 15 67 default "4" 67 default "4" 68 help 68 help 69 loglevel to use when "quiet" is pass 69 loglevel to use when "quiet" is passed on the kernel commandline. 70 70 71 When "quiet" is passed on the kernel 71 When "quiet" is passed on the kernel commandline this loglevel 72 will be used as the loglevel. IOW pa 72 will be used as the loglevel. IOW passing "quiet" will be the 73 equivalent of passing "loglevel=<CON 73 equivalent of passing "loglevel=<CONSOLE_LOGLEVEL_QUIET>" 74 74 75 config MESSAGE_LOGLEVEL_DEFAULT 75 config MESSAGE_LOGLEVEL_DEFAULT 76 int "Default message log level (1-7)" 76 int "Default message log level (1-7)" 77 range 1 7 77 range 1 7 78 default "4" 78 default "4" 79 help 79 help 80 Default log level for printk stateme 80 Default log level for printk statements with no specified priority. 81 81 82 This was hard-coded to KERN_WARNING 82 This was hard-coded to KERN_WARNING since at least 2.6.10 but folks 83 that are auditing their logs closely 83 that are auditing their logs closely may want to set it to a lower 84 priority. 84 priority. 85 85 86 Note: This does not affect what mess 86 Note: This does not affect what message level gets printed on the console 87 by default. To change that, use logl 87 by default. To change that, use loglevel=<x> in the kernel bootargs, 88 or pick a different CONSOLE_LOGLEVEL 88 or pick a different CONSOLE_LOGLEVEL_DEFAULT configuration value. 89 89 90 config BOOT_PRINTK_DELAY 90 config BOOT_PRINTK_DELAY 91 bool "Delay each boot printk message b 91 bool "Delay each boot printk message by N milliseconds" 92 depends on DEBUG_KERNEL && PRINTK && G 92 depends on DEBUG_KERNEL && PRINTK && GENERIC_CALIBRATE_DELAY 93 help 93 help 94 This build option allows you to read 94 This build option allows you to read kernel boot messages 95 by inserting a short delay after eac 95 by inserting a short delay after each one. The delay is 96 specified in milliseconds on the ker 96 specified in milliseconds on the kernel command line, 97 using "boot_delay=N". 97 using "boot_delay=N". 98 98 99 It is likely that you would also nee 99 It is likely that you would also need to use "lpj=M" to preset 100 the "loops per jiffie" value. 100 the "loops per jiffie" value. 101 See a previous boot log for the "lpj 101 See a previous boot log for the "lpj" value to use for your 102 system, and then set "lpj=M" before 102 system, and then set "lpj=M" before setting "boot_delay=N". 103 NOTE: Using this option may adverse 103 NOTE: Using this option may adversely affect SMP systems. 104 I.e., processors other than the firs 104 I.e., processors other than the first one may not boot up. 105 BOOT_PRINTK_DELAY also may cause LOC 105 BOOT_PRINTK_DELAY also may cause LOCKUP_DETECTOR to detect 106 what it believes to be lockup condit 106 what it believes to be lockup conditions. 107 107 108 config DYNAMIC_DEBUG 108 config DYNAMIC_DEBUG 109 bool "Enable dynamic printk() support" 109 bool "Enable dynamic printk() support" 110 default n 110 default n 111 depends on PRINTK 111 depends on PRINTK 112 depends on (DEBUG_FS || PROC_FS) 112 depends on (DEBUG_FS || PROC_FS) 113 select DYNAMIC_DEBUG_CORE 113 select DYNAMIC_DEBUG_CORE 114 help 114 help 115 115 116 Compiles debug level messages into t 116 Compiles debug level messages into the kernel, which would not 117 otherwise be available at runtime. T 117 otherwise be available at runtime. These messages can then be 118 enabled/disabled based on various le 118 enabled/disabled based on various levels of scope - per source file, 119 function, module, format string, and 119 function, module, format string, and line number. This mechanism 120 implicitly compiles in all pr_debug( 120 implicitly compiles in all pr_debug() and dev_dbg() calls, which 121 enlarges the kernel text size by abo 121 enlarges the kernel text size by about 2%. 122 122 123 If a source file is compiled with DE 123 If a source file is compiled with DEBUG flag set, any 124 pr_debug() calls in it are enabled b 124 pr_debug() calls in it are enabled by default, but can be 125 disabled at runtime as below. Note 125 disabled at runtime as below. Note that DEBUG flag is 126 turned on by many CONFIG_*DEBUG* opt 126 turned on by many CONFIG_*DEBUG* options. 127 127 128 Usage: 128 Usage: 129 129 130 Dynamic debugging is controlled via 130 Dynamic debugging is controlled via the 'dynamic_debug/control' file, 131 which is contained in the 'debugfs' 131 which is contained in the 'debugfs' filesystem or procfs. 132 Thus, the debugfs or procfs filesyst 132 Thus, the debugfs or procfs filesystem must first be mounted before 133 making use of this feature. 133 making use of this feature. 134 We refer the control file as: <debug 134 We refer the control file as: <debugfs>/dynamic_debug/control. This 135 file contains a list of the debug st 135 file contains a list of the debug statements that can be enabled. The 136 format for each line of the file is: 136 format for each line of the file is: 137 137 138 filename:lineno [module]functi 138 filename:lineno [module]function flags format 139 139 140 filename : source file of the debug 140 filename : source file of the debug statement 141 lineno : line number of the debug st 141 lineno : line number of the debug statement 142 module : module that contains the de 142 module : module that contains the debug statement 143 function : function that contains th 143 function : function that contains the debug statement 144 flags : '=p' means the line is turne 144 flags : '=p' means the line is turned 'on' for printing 145 format : the format used for the deb 145 format : the format used for the debug statement 146 146 147 From a live system: 147 From a live system: 148 148 149 nullarbor:~ # cat <debugfs>/dy 149 nullarbor:~ # cat <debugfs>/dynamic_debug/control 150 # filename:lineno [module]func 150 # filename:lineno [module]function flags format 151 fs/aio.c:222 [aio]__put_ioctx 151 fs/aio.c:222 [aio]__put_ioctx =_ "__put_ioctx:\040freeing\040%p\012" 152 fs/aio.c:248 [aio]ioctx_alloc 152 fs/aio.c:248 [aio]ioctx_alloc =_ "ENOMEM:\040nr_events\040too\040high\012" 153 fs/aio.c:1770 [aio]sys_io_canc 153 fs/aio.c:1770 [aio]sys_io_cancel =_ "calling\040cancel\012" 154 154 155 Example usage: 155 Example usage: 156 156 157 // enable the message at line 157 // enable the message at line 1603 of file svcsock.c 158 nullarbor:~ # echo -n 'file sv 158 nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > 159 159 <debugfs>/dynamic_debug/control 160 160 161 // enable all the messages in 161 // enable all the messages in file svcsock.c 162 nullarbor:~ # echo -n 'file sv 162 nullarbor:~ # echo -n 'file svcsock.c +p' > 163 163 <debugfs>/dynamic_debug/control 164 164 165 // enable all the messages in 165 // enable all the messages in the NFS server module 166 nullarbor:~ # echo -n 'module 166 nullarbor:~ # echo -n 'module nfsd +p' > 167 167 <debugfs>/dynamic_debug/control 168 168 169 // enable all 12 messages in t 169 // enable all 12 messages in the function svc_process() 170 nullarbor:~ # echo -n 'func sv 170 nullarbor:~ # echo -n 'func svc_process +p' > 171 171 <debugfs>/dynamic_debug/control 172 172 173 // disable all 12 messages in 173 // disable all 12 messages in the function svc_process() 174 nullarbor:~ # echo -n 'func sv 174 nullarbor:~ # echo -n 'func svc_process -p' > 175 175 <debugfs>/dynamic_debug/control 176 176 177 See Documentation/admin-guide/dynami 177 See Documentation/admin-guide/dynamic-debug-howto.rst for additional 178 information. 178 information. 179 179 180 config DYNAMIC_DEBUG_CORE 180 config DYNAMIC_DEBUG_CORE 181 bool "Enable core function of dynamic 181 bool "Enable core function of dynamic debug support" 182 depends on PRINTK 182 depends on PRINTK 183 depends on (DEBUG_FS || PROC_FS) 183 depends on (DEBUG_FS || PROC_FS) 184 help 184 help 185 Enable core functional support of dy 185 Enable core functional support of dynamic debug. It is useful 186 when you want to tie dynamic debug t 186 when you want to tie dynamic debug to your kernel modules with 187 DYNAMIC_DEBUG_MODULE defined for eac 187 DYNAMIC_DEBUG_MODULE defined for each of them, especially for 188 the case of embedded system where th 188 the case of embedded system where the kernel image size is 189 sensitive for people. 189 sensitive for people. 190 190 191 config SYMBOLIC_ERRNAME 191 config SYMBOLIC_ERRNAME 192 bool "Support symbolic error names in 192 bool "Support symbolic error names in printf" 193 default y if PRINTK 193 default y if PRINTK 194 help 194 help 195 If you say Y here, the kernel's prin 195 If you say Y here, the kernel's printf implementation will 196 be able to print symbolic error name 196 be able to print symbolic error names such as ENOSPC instead 197 of the number 28. It makes the kerne 197 of the number 28. It makes the kernel image slightly larger 198 (about 3KB), but can make the kernel 198 (about 3KB), but can make the kernel logs easier to read. 199 199 200 config DEBUG_BUGVERBOSE 200 config DEBUG_BUGVERBOSE 201 bool "Verbose BUG() reporting (adds 70 201 bool "Verbose BUG() reporting (adds 70K)" if DEBUG_KERNEL && EXPERT 202 depends on BUG && (GENERIC_BUG || HAVE 202 depends on BUG && (GENERIC_BUG || HAVE_DEBUG_BUGVERBOSE) 203 default y 203 default y 204 help 204 help 205 Say Y here to make BUG() panics outp 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 a 206 of the BUG call as well as the EIP and oops trace. This aids 207 debugging but costs about 70-100K of 207 debugging but costs about 70-100K of memory. 208 208 209 endmenu # "printk and dmesg options" 209 endmenu # "printk and dmesg options" 210 210 211 config DEBUG_KERNEL 211 config DEBUG_KERNEL 212 bool "Kernel debugging" 212 bool "Kernel debugging" 213 help 213 help 214 Say Y here if you are developing dri 214 Say Y here if you are developing drivers or trying to debug and 215 identify kernel problems. 215 identify kernel problems. 216 216 217 config DEBUG_MISC 217 config DEBUG_MISC 218 bool "Miscellaneous debug code" 218 bool "Miscellaneous debug code" 219 default DEBUG_KERNEL 219 default DEBUG_KERNEL 220 depends on DEBUG_KERNEL 220 depends on DEBUG_KERNEL 221 help 221 help 222 Say Y here if you need to enable mis 222 Say Y here if you need to enable miscellaneous debug code that should 223 be under a more specific debug optio 223 be under a more specific debug option but isn't. 224 224 225 menu "Compile-time checks and compiler options 225 menu "Compile-time checks and compiler options" 226 226 227 config DEBUG_INFO 227 config DEBUG_INFO 228 bool 228 bool 229 help 229 help 230 A kernel debug info option other tha 230 A kernel debug info option other than "None" has been selected 231 in the "Debug information" choice be 231 in the "Debug information" choice below, indicating that debug 232 information will be generated for bu 232 information will be generated for build targets. 233 233 234 # Clang generates .uleb128 with label differen !! 234 # Clang is known to generate .{s,u}leb128 with symbol deltas with DWARF5, which 235 # older binutils ports do not support when uti !! 235 # some targets may not support: https://sourceware.org/bugzilla/show_bug.cgi?id=27215 236 # relaxation: https://sourceware.org/bugzilla/ !! 236 config AS_HAS_NON_CONST_LEB128 237 config AS_HAS_NON_CONST_ULEB128 << 238 def_bool $(as-instr,.uleb128 .Lexpr_en 237 def_bool $(as-instr,.uleb128 .Lexpr_end4 - .Lexpr_start3\n.Lexpr_start3:\n.Lexpr_end4:) 239 238 240 choice 239 choice 241 prompt "Debug information" 240 prompt "Debug information" 242 depends on DEBUG_KERNEL 241 depends on DEBUG_KERNEL 243 help 242 help 244 Selecting something other than "None 243 Selecting something other than "None" results in a kernel image 245 that will include debugging info res 244 that will include debugging info resulting in a larger kernel image. 246 This adds debug symbols to the kerne 245 This adds debug symbols to the kernel and modules (gcc -g), and 247 is needed if you intend to use kerne 246 is needed if you intend to use kernel crashdump or binary object 248 tools like crash, kgdb, LKCD, gdb, e 247 tools like crash, kgdb, LKCD, gdb, etc on the kernel. 249 248 250 Choose which version of DWARF debug 249 Choose which version of DWARF debug info to emit. If unsure, 251 select "Toolchain default". 250 select "Toolchain default". 252 251 253 config DEBUG_INFO_NONE 252 config DEBUG_INFO_NONE 254 bool "Disable debug information" 253 bool "Disable debug information" 255 help 254 help 256 Do not build the kernel with debuggi 255 Do not build the kernel with debugging information, which will 257 result in a faster and smaller build 256 result in a faster and smaller build. 258 257 259 config DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT 258 config DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT 260 bool "Rely on the toolchain's implicit 259 bool "Rely on the toolchain's implicit default DWARF version" 261 select DEBUG_INFO 260 select DEBUG_INFO 262 depends on !CC_IS_CLANG || AS_IS_LLVM !! 261 depends on !CC_IS_CLANG || AS_IS_LLVM || CLANG_VERSION < 140000 || (AS_IS_GNU && AS_VERSION >= 23502 && AS_HAS_NON_CONST_LEB128) 263 help 262 help 264 The implicit default version of DWAR 263 The implicit default version of DWARF debug info produced by a 265 toolchain changes over time. 264 toolchain changes over time. 266 265 267 This can break consumers of the debu 266 This can break consumers of the debug info that haven't upgraded to 268 support newer revisions, and prevent 267 support newer revisions, and prevent testing newer versions, but 269 those should be less common scenario 268 those should be less common scenarios. 270 269 271 config DEBUG_INFO_DWARF4 270 config DEBUG_INFO_DWARF4 272 bool "Generate DWARF Version 4 debugin 271 bool "Generate DWARF Version 4 debuginfo" 273 select DEBUG_INFO 272 select DEBUG_INFO 274 depends on !CC_IS_CLANG || AS_IS_LLVM 273 depends on !CC_IS_CLANG || AS_IS_LLVM || (AS_IS_GNU && AS_VERSION >= 23502) 275 help 274 help 276 Generate DWARF v4 debug info. This r 275 Generate DWARF v4 debug info. This requires gcc 4.5+, binutils 2.35.2 277 if using clang without clang's integ 276 if using clang without clang's integrated assembler, and gdb 7.0+. 278 277 279 If you have consumers of DWARF debug 278 If you have consumers of DWARF debug info that are not ready for 280 newer revisions of DWARF, you may wi 279 newer revisions of DWARF, you may wish to choose this or have your 281 config select this. 280 config select this. 282 281 283 config DEBUG_INFO_DWARF5 282 config DEBUG_INFO_DWARF5 284 bool "Generate DWARF Version 5 debugin 283 bool "Generate DWARF Version 5 debuginfo" 285 select DEBUG_INFO 284 select DEBUG_INFO 286 depends on !ARCH_HAS_BROKEN_DWARF5 !! 285 depends on !CC_IS_CLANG || AS_IS_LLVM || (AS_IS_GNU && AS_VERSION >= 23502 && AS_HAS_NON_CONST_LEB128) 287 depends on !CC_IS_CLANG || AS_IS_LLVM << 288 help 286 help 289 Generate DWARF v5 debug info. Requir 287 Generate DWARF v5 debug info. Requires binutils 2.35.2, gcc 5.0+ (gcc 290 5.0+ accepts the -gdwarf-5 flag but 288 5.0+ accepts the -gdwarf-5 flag but only had partial support for some 291 draft features until 7.0), and gdb 8 289 draft features until 7.0), and gdb 8.0+. 292 290 293 Changes to the structure of debug in 291 Changes to the structure of debug info in Version 5 allow for around 294 15-18% savings in resulting image an 292 15-18% savings in resulting image and debug info section sizes as 295 compared to DWARF Version 4. DWARF V 293 compared to DWARF Version 4. DWARF Version 5 standardizes previous 296 extensions such as accelerators for 294 extensions such as accelerators for symbol indexing and the format 297 for fission (.dwo/.dwp) files. Users 295 for fission (.dwo/.dwp) files. Users may not want to select this 298 config if they rely on tooling that 296 config if they rely on tooling that has not yet been updated to 299 support DWARF Version 5. 297 support DWARF Version 5. 300 298 301 endchoice # "Debug information" 299 endchoice # "Debug information" 302 300 303 if DEBUG_INFO 301 if DEBUG_INFO 304 302 305 config DEBUG_INFO_REDUCED 303 config DEBUG_INFO_REDUCED 306 bool "Reduce debugging information" 304 bool "Reduce debugging information" 307 help 305 help 308 If you say Y here gcc is instructed 306 If you say Y here gcc is instructed to generate less debugging 309 information for structure types. Thi 307 information for structure types. This means that tools that 310 need full debugging information (lik 308 need full debugging information (like kgdb or systemtap) won't 311 be happy. But if you merely need deb 309 be happy. But if you merely need debugging information to 312 resolve line numbers there is no los 310 resolve line numbers there is no loss. Advantage is that 313 build directory object sizes shrink 311 build directory object sizes shrink dramatically over a full 314 DEBUG_INFO build and compile times a 312 DEBUG_INFO build and compile times are reduced too. 315 Only works with newer gcc versions. 313 Only works with newer gcc versions. 316 314 317 choice 315 choice 318 prompt "Compressed Debug information" 316 prompt "Compressed Debug information" 319 help 317 help 320 Compress the resulting debug info. R 318 Compress the resulting debug info. Results in smaller debug info sections, 321 but requires that consumers are able 319 but requires that consumers are able to decompress the results. 322 320 323 If unsure, choose DEBUG_INFO_COMPRES 321 If unsure, choose DEBUG_INFO_COMPRESSED_NONE. 324 322 325 config DEBUG_INFO_COMPRESSED_NONE 323 config DEBUG_INFO_COMPRESSED_NONE 326 bool "Don't compress debug information 324 bool "Don't compress debug information" 327 help 325 help 328 Don't compress debug info sections. 326 Don't compress debug info sections. 329 327 330 config DEBUG_INFO_COMPRESSED_ZLIB 328 config DEBUG_INFO_COMPRESSED_ZLIB 331 bool "Compress debugging information w 329 bool "Compress debugging information with zlib" 332 depends on $(cc-option,-gz=zlib) 330 depends on $(cc-option,-gz=zlib) 333 depends on $(ld-option,--compress-debu 331 depends on $(ld-option,--compress-debug-sections=zlib) 334 help 332 help 335 Compress the debug information using 333 Compress the debug information using zlib. Requires GCC 5.0+ or Clang 336 5.0+, binutils 2.26+, and zlib. 334 5.0+, binutils 2.26+, and zlib. 337 335 338 Users of dpkg-deb via scripts/packag 336 Users of dpkg-deb via scripts/package/builddeb may find an increase in 339 size of their debug .deb packages wi 337 size of their debug .deb packages with this config set, due to the 340 debug info being compressed with zli 338 debug info being compressed with zlib, then the object files being 341 recompressed with a different compre 339 recompressed with a different compression scheme. But this is still 342 preferable to setting $KDEB_COMPRESS 340 preferable to setting $KDEB_COMPRESS to "none" which would be even 343 larger. 341 larger. 344 342 345 config DEBUG_INFO_COMPRESSED_ZSTD 343 config DEBUG_INFO_COMPRESSED_ZSTD 346 bool "Compress debugging information w 344 bool "Compress debugging information with zstd" 347 depends on $(cc-option,-gz=zstd) 345 depends on $(cc-option,-gz=zstd) 348 depends on $(ld-option,--compress-debu 346 depends on $(ld-option,--compress-debug-sections=zstd) 349 help 347 help 350 Compress the debug information using 348 Compress the debug information using zstd. This may provide better 351 compression than zlib, for about the 349 compression than zlib, for about the same time costs, but requires newer 352 toolchain support. Requires GCC 13. 350 toolchain support. Requires GCC 13.0+ or Clang 16.0+, binutils 2.40+, and 353 zstd. 351 zstd. 354 352 355 endchoice # "Compressed Debug information" 353 endchoice # "Compressed Debug information" 356 354 357 config DEBUG_INFO_SPLIT 355 config DEBUG_INFO_SPLIT 358 bool "Produce split debuginfo in .dwo 356 bool "Produce split debuginfo in .dwo files" 359 depends on $(cc-option,-gsplit-dwarf) 357 depends on $(cc-option,-gsplit-dwarf) 360 # RISC-V linker relaxation + -gsplit-d << 361 # prior to 12.x: << 362 # https://github.com/llvm/llvm-project << 363 # https://gcc.gnu.org/bugzilla/show_bu << 364 depends on !RISCV || GCC_VERSION >= 12 << 365 help 358 help 366 Generate debug info into separate .d 359 Generate debug info into separate .dwo files. This significantly 367 reduces the build directory size for 360 reduces the build directory size for builds with DEBUG_INFO, 368 because it stores the information on 361 because it stores the information only once on disk in .dwo 369 files instead of multiple times in o 362 files instead of multiple times in object files and executables. 370 In addition the debug information is 363 In addition the debug information is also compressed. 371 364 372 Requires recent gcc (4.7+) and recen 365 Requires recent gcc (4.7+) and recent gdb/binutils. 373 Any tool that packages or reads debu 366 Any tool that packages or reads debug information would need 374 to know about the .dwo files and inc 367 to know about the .dwo files and include them. 375 Incompatible with older versions of 368 Incompatible with older versions of ccache. 376 369 377 config DEBUG_INFO_BTF 370 config DEBUG_INFO_BTF 378 bool "Generate BTF type information" !! 371 bool "Generate BTF typeinfo" 379 depends on !DEBUG_INFO_SPLIT && !DEBUG 372 depends on !DEBUG_INFO_SPLIT && !DEBUG_INFO_REDUCED 380 depends on !GCC_PLUGIN_RANDSTRUCT || C 373 depends on !GCC_PLUGIN_RANDSTRUCT || COMPILE_TEST 381 depends on BPF_SYSCALL 374 depends on BPF_SYSCALL 382 depends on !DEBUG_INFO_DWARF5 || PAHOL 375 depends on !DEBUG_INFO_DWARF5 || PAHOLE_VERSION >= 121 383 # pahole uses elfutils, which does not << 384 depends on !HEXAGON << 385 help 376 help 386 Generate deduplicated BTF type infor 377 Generate deduplicated BTF type information from DWARF debug info. 387 Turning this on expects presence of 378 Turning this on expects presence of pahole tool, which will convert 388 DWARF type info into equivalent dedu 379 DWARF type info into equivalent deduplicated BTF type info. 389 380 390 config PAHOLE_HAS_SPLIT_BTF 381 config PAHOLE_HAS_SPLIT_BTF 391 def_bool PAHOLE_VERSION >= 119 382 def_bool PAHOLE_VERSION >= 119 392 383 393 config PAHOLE_HAS_BTF_TAG 384 config PAHOLE_HAS_BTF_TAG 394 def_bool PAHOLE_VERSION >= 123 385 def_bool PAHOLE_VERSION >= 123 395 depends on CC_IS_CLANG 386 depends on CC_IS_CLANG 396 help 387 help 397 Decide whether pahole emits btf_tag 388 Decide whether pahole emits btf_tag attributes (btf_type_tag and 398 btf_decl_tag) or not. Currently only 389 btf_decl_tag) or not. Currently only clang compiler implements 399 these attributes, so make the config 390 these attributes, so make the config depend on CC_IS_CLANG. 400 391 401 config PAHOLE_HAS_LANG_EXCLUDE 392 config PAHOLE_HAS_LANG_EXCLUDE 402 def_bool PAHOLE_VERSION >= 124 393 def_bool PAHOLE_VERSION >= 124 403 help 394 help 404 Support for the --lang_exclude flag 395 Support for the --lang_exclude flag which makes pahole exclude 405 compilation units from the supplied 396 compilation units from the supplied language. Used in Kbuild to 406 omit Rust CUs which are not supporte 397 omit Rust CUs which are not supported in version 1.24 of pahole, 407 otherwise it would emit malformed ke 398 otherwise it would emit malformed kernel and module binaries when 408 using DEBUG_INFO_BTF_MODULES. 399 using DEBUG_INFO_BTF_MODULES. 409 400 410 config DEBUG_INFO_BTF_MODULES 401 config DEBUG_INFO_BTF_MODULES 411 bool "Generate BTF type information fo !! 402 def_bool y 412 default y << 413 depends on DEBUG_INFO_BTF && MODULES & 403 depends on DEBUG_INFO_BTF && MODULES && PAHOLE_HAS_SPLIT_BTF 414 help 404 help 415 Generate compact split BTF type info 405 Generate compact split BTF type information for kernel modules. 416 406 417 config MODULE_ALLOW_BTF_MISMATCH 407 config MODULE_ALLOW_BTF_MISMATCH 418 bool "Allow loading modules with non-m 408 bool "Allow loading modules with non-matching BTF type info" 419 depends on DEBUG_INFO_BTF_MODULES 409 depends on DEBUG_INFO_BTF_MODULES 420 help 410 help 421 For modules whose split BTF does not 411 For modules whose split BTF does not match vmlinux, load without 422 BTF rather than refusing to load. Th 412 BTF rather than refusing to load. The default behavior with 423 module BTF enabled is to reject modu 413 module BTF enabled is to reject modules with such mismatches; 424 this option will still load module B 414 this option will still load module BTF where possible but ignore 425 it when a mismatch is found. 415 it when a mismatch is found. 426 416 427 config GDB_SCRIPTS 417 config GDB_SCRIPTS 428 bool "Provide GDB scripts for kernel d 418 bool "Provide GDB scripts for kernel debugging" 429 help 419 help 430 This creates the required links to G 420 This creates the required links to GDB helper scripts in the 431 build directory. If you load vmlinux 421 build directory. If you load vmlinux into gdb, the helper 432 scripts will be automatically import 422 scripts will be automatically imported by gdb as well, and 433 additional functions are available t 423 additional functions are available to analyze a Linux kernel 434 instance. See Documentation/dev-tool 424 instance. See Documentation/dev-tools/gdb-kernel-debugging.rst 435 for further details. 425 for further details. 436 426 437 endif # DEBUG_INFO 427 endif # DEBUG_INFO 438 428 439 config FRAME_WARN 429 config FRAME_WARN 440 int "Warn for stack frames larger than 430 int "Warn for stack frames larger than" 441 range 0 8192 431 range 0 8192 442 default 0 if KMSAN 432 default 0 if KMSAN 443 default 2048 if GCC_PLUGIN_LATENT_ENTR 433 default 2048 if GCC_PLUGIN_LATENT_ENTROPY 444 default 2048 if PARISC 434 default 2048 if PARISC 445 default 1536 if (!64BIT && XTENSA) 435 default 1536 if (!64BIT && XTENSA) 446 default 1280 if KASAN && !64BIT 436 default 1280 if KASAN && !64BIT 447 default 1024 if !64BIT 437 default 1024 if !64BIT 448 default 2048 if 64BIT 438 default 2048 if 64BIT 449 help 439 help 450 Tell the compiler to warn at build t 440 Tell the compiler to warn at build time for stack frames larger than this. 451 Setting this too low will cause a lo 441 Setting this too low will cause a lot of warnings. 452 Setting it to 0 disables the warning 442 Setting it to 0 disables the warning. 453 443 454 config STRIP_ASM_SYMS 444 config STRIP_ASM_SYMS 455 bool "Strip assembler-generated symbol 445 bool "Strip assembler-generated symbols during link" 456 default n 446 default n 457 help 447 help 458 Strip internal assembler-generated s 448 Strip internal assembler-generated symbols during a link (symbols 459 that look like '.Lxxx') so they don' 449 that look like '.Lxxx') so they don't pollute the output of 460 get_wchan() and suchlike. 450 get_wchan() and suchlike. 461 451 462 config READABLE_ASM 452 config READABLE_ASM 463 bool "Generate readable assembler code 453 bool "Generate readable assembler code" 464 depends on DEBUG_KERNEL 454 depends on DEBUG_KERNEL 465 depends on CC_IS_GCC 455 depends on CC_IS_GCC 466 help 456 help 467 Disable some compiler optimizations 457 Disable some compiler optimizations that tend to generate human unreadable 468 assembler output. This may make the 458 assembler output. This may make the kernel slightly slower, but it helps 469 to keep kernel developers who have t 459 to keep kernel developers who have to stare a lot at assembler listings 470 sane. 460 sane. 471 461 472 config HEADERS_INSTALL 462 config HEADERS_INSTALL 473 bool "Install uapi headers to usr/incl 463 bool "Install uapi headers to usr/include" 474 depends on !UML 464 depends on !UML 475 help 465 help 476 This option will install uapi header 466 This option will install uapi headers (headers exported to user-space) 477 into the usr/include directory for u 467 into the usr/include directory for use during the kernel build. 478 This is unneeded for building the ke 468 This is unneeded for building the kernel itself, but needed for some 479 user-space program samples. It is al 469 user-space program samples. It is also needed by some features such 480 as uapi header sanity checks. 470 as uapi header sanity checks. 481 471 482 config DEBUG_SECTION_MISMATCH 472 config DEBUG_SECTION_MISMATCH 483 bool "Enable full Section mismatch ana 473 bool "Enable full Section mismatch analysis" 484 depends on CC_IS_GCC 474 depends on CC_IS_GCC 485 help 475 help 486 The section mismatch analysis checks 476 The section mismatch analysis checks if there are illegal 487 references from one section to anoth 477 references from one section to another section. 488 During linktime or runtime, some sec 478 During linktime or runtime, some sections are dropped; 489 any use of code/data previously in t 479 any use of code/data previously in these sections would 490 most likely result in an oops. 480 most likely result in an oops. 491 In the code, functions and variables 481 In the code, functions and variables are annotated with 492 __init,, etc. (see the full list in 482 __init,, etc. (see the full list in include/linux/init.h), 493 which results in the code/data being 483 which results in the code/data being placed in specific sections. 494 The section mismatch analysis is alw 484 The section mismatch analysis is always performed after a full 495 kernel build, and enabling this opti 485 kernel build, and enabling this option causes the following 496 additional step to occur: 486 additional step to occur: 497 - Add the option -fno-inline-functio 487 - Add the option -fno-inline-functions-called-once to gcc commands. 498 When inlining a function annotated 488 When inlining a function annotated with __init in a non-init 499 function, we would lose the sectio 489 function, we would lose the section information and thus 500 the analysis would not catch the i 490 the analysis would not catch the illegal reference. 501 This option tells gcc to inline le 491 This option tells gcc to inline less (but it does result in 502 a larger kernel). 492 a larger kernel). 503 493 504 config SECTION_MISMATCH_WARN_ONLY 494 config SECTION_MISMATCH_WARN_ONLY 505 bool "Make section mismatch errors non 495 bool "Make section mismatch errors non-fatal" 506 default y 496 default y 507 help 497 help 508 If you say N here, the build process 498 If you say N here, the build process will fail if there are any 509 section mismatch, instead of just th 499 section mismatch, instead of just throwing warnings. 510 500 511 If unsure, say Y. 501 If unsure, say Y. 512 502 513 config DEBUG_FORCE_FUNCTION_ALIGN_64B 503 config DEBUG_FORCE_FUNCTION_ALIGN_64B 514 bool "Force all function address 64B a 504 bool "Force all function address 64B aligned" 515 depends on EXPERT && (X86_64 || ARM64 !! 505 depends on EXPERT && (X86_64 || ARM64 || PPC32 || PPC64 || ARC || S390) 516 select FUNCTION_ALIGNMENT_64B 506 select FUNCTION_ALIGNMENT_64B 517 help 507 help 518 There are cases that a commit from o 508 There are cases that a commit from one domain changes the function 519 address alignment of other domains, 509 address alignment of other domains, and cause magic performance 520 bump (regression or improvement). En 510 bump (regression or improvement). Enable this option will help to 521 verify if the bump is caused by func 511 verify if the bump is caused by function alignment changes, while 522 it will slightly increase the kernel 512 it will slightly increase the kernel size and affect icache usage. 523 513 524 It is mainly for debug and performan 514 It is mainly for debug and performance tuning use. 525 515 526 # 516 # 527 # Select this config option from the architect 517 # Select this config option from the architecture Kconfig, if it 528 # is preferred to always offer frame pointers 518 # is preferred to always offer frame pointers as a config 529 # option on the architecture (regardless of KE 519 # option on the architecture (regardless of KERNEL_DEBUG): 530 # 520 # 531 config ARCH_WANT_FRAME_POINTERS 521 config ARCH_WANT_FRAME_POINTERS 532 bool 522 bool 533 523 534 config FRAME_POINTER 524 config FRAME_POINTER 535 bool "Compile the kernel with frame po 525 bool "Compile the kernel with frame pointers" 536 depends on DEBUG_KERNEL && (M68K || UM 526 depends on DEBUG_KERNEL && (M68K || UML || SUPERH) || ARCH_WANT_FRAME_POINTERS 537 default y if (DEBUG_INFO && UML) || AR 527 default y if (DEBUG_INFO && UML) || ARCH_WANT_FRAME_POINTERS 538 help 528 help 539 If you say Y here the resulting kern 529 If you say Y here the resulting kernel image will be slightly 540 larger and slower, but it gives very 530 larger and slower, but it gives very useful debugging information 541 in case of kernel bugs. (precise oop 531 in case of kernel bugs. (precise oopses/stacktraces/warnings) 542 532 543 config OBJTOOL 533 config OBJTOOL 544 bool 534 bool 545 535 546 config STACK_VALIDATION 536 config STACK_VALIDATION 547 bool "Compile-time stack metadata vali 537 bool "Compile-time stack metadata validation" 548 depends on HAVE_STACK_VALIDATION && UN 538 depends on HAVE_STACK_VALIDATION && UNWINDER_FRAME_POINTER 549 select OBJTOOL 539 select OBJTOOL 550 default n 540 default n 551 help 541 help 552 Validate frame pointer rules at comp 542 Validate frame pointer rules at compile-time. This helps ensure that 553 runtime stack traces are more reliab 543 runtime stack traces are more reliable. 554 544 555 For more information, see 545 For more information, see 556 tools/objtool/Documentation/objtool. 546 tools/objtool/Documentation/objtool.txt. 557 547 558 config NOINSTR_VALIDATION 548 config NOINSTR_VALIDATION 559 bool 549 bool 560 depends on HAVE_NOINSTR_VALIDATION && 550 depends on HAVE_NOINSTR_VALIDATION && DEBUG_ENTRY 561 select OBJTOOL 551 select OBJTOOL 562 default y 552 default y 563 553 564 config VMLINUX_MAP 554 config VMLINUX_MAP 565 bool "Generate vmlinux.map file when l 555 bool "Generate vmlinux.map file when linking" 566 depends on EXPERT 556 depends on EXPERT 567 help 557 help 568 Selecting this option will pass "-Ma 558 Selecting this option will pass "-Map=vmlinux.map" to ld 569 when linking vmlinux. That file can 559 when linking vmlinux. That file can be useful for verifying 570 and debugging magic section games, a 560 and debugging magic section games, and for seeing which 571 pieces of code get eliminated with 561 pieces of code get eliminated with 572 CONFIG_LD_DEAD_CODE_DATA_ELIMINATION 562 CONFIG_LD_DEAD_CODE_DATA_ELIMINATION. 573 563 574 config DEBUG_FORCE_WEAK_PER_CPU 564 config DEBUG_FORCE_WEAK_PER_CPU 575 bool "Force weak per-cpu definitions" 565 bool "Force weak per-cpu definitions" 576 depends on DEBUG_KERNEL 566 depends on DEBUG_KERNEL 577 help 567 help 578 s390 and alpha require percpu variab 568 s390 and alpha require percpu variables in modules to be 579 defined weak to work around addressi 569 defined weak to work around addressing range issue which 580 puts the following two restrictions 570 puts the following two restrictions on percpu variable 581 definitions. 571 definitions. 582 572 583 1. percpu symbols must be unique whe 573 1. percpu symbols must be unique whether static or not 584 2. percpu variables can't be defined 574 2. percpu variables can't be defined inside a function 585 575 586 To ensure that generic code follows 576 To ensure that generic code follows the above rules, this 587 option forces all percpu variables t 577 option forces all percpu variables to be defined as weak. 588 578 589 endmenu # "Compiler options" 579 endmenu # "Compiler options" 590 580 591 menu "Generic Kernel Debugging Instruments" 581 menu "Generic Kernel Debugging Instruments" 592 582 593 config MAGIC_SYSRQ 583 config MAGIC_SYSRQ 594 bool "Magic SysRq key" 584 bool "Magic SysRq key" 595 depends on !UML 585 depends on !UML 596 help 586 help 597 If you say Y here, you will have som 587 If you say Y here, you will have some control over the system even 598 if the system crashes for example du 588 if the system crashes for example during kernel debugging (e.g., you 599 will be able to flush the buffer cac 589 will be able to flush the buffer cache to disk, reboot the system 600 immediately or dump some status info 590 immediately or dump some status information). This is accomplished 601 by pressing various keys while holdi 591 by pressing various keys while holding SysRq (Alt+PrintScreen). It 602 also works on a serial console (on P 592 also works on a serial console (on PC hardware at least), if you 603 send a BREAK and then within 5 secon 593 send a BREAK and then within 5 seconds a command keypress. The 604 keys are documented in <file:Documen 594 keys are documented in <file:Documentation/admin-guide/sysrq.rst>. 605 Don't say Y unless you really know w 595 Don't say Y unless you really know what this hack does. 606 596 607 config MAGIC_SYSRQ_DEFAULT_ENABLE 597 config MAGIC_SYSRQ_DEFAULT_ENABLE 608 hex "Enable magic SysRq key functions 598 hex "Enable magic SysRq key functions by default" 609 depends on MAGIC_SYSRQ 599 depends on MAGIC_SYSRQ 610 default 0x1 600 default 0x1 611 help 601 help 612 Specifies which SysRq key functions 602 Specifies which SysRq key functions are enabled by default. 613 This may be set to 1 or 0 to enable 603 This may be set to 1 or 0 to enable or disable them all, or 614 to a bitmask as described in Documen 604 to a bitmask as described in Documentation/admin-guide/sysrq.rst. 615 605 616 config MAGIC_SYSRQ_SERIAL 606 config MAGIC_SYSRQ_SERIAL 617 bool "Enable magic SysRq key over seri 607 bool "Enable magic SysRq key over serial" 618 depends on MAGIC_SYSRQ 608 depends on MAGIC_SYSRQ 619 default y 609 default y 620 help 610 help 621 Many embedded boards have a disconne 611 Many embedded boards have a disconnected TTL level serial which can 622 generate some garbage that can lead 612 generate some garbage that can lead to spurious false sysrq detects. 623 This option allows you to decide whe 613 This option allows you to decide whether you want to enable the 624 magic SysRq key. 614 magic SysRq key. 625 615 626 config MAGIC_SYSRQ_SERIAL_SEQUENCE 616 config MAGIC_SYSRQ_SERIAL_SEQUENCE 627 string "Char sequence that enables mag 617 string "Char sequence that enables magic SysRq over serial" 628 depends on MAGIC_SYSRQ_SERIAL 618 depends on MAGIC_SYSRQ_SERIAL 629 default "" 619 default "" 630 help 620 help 631 Specifies a sequence of characters t 621 Specifies a sequence of characters that can follow BREAK to enable 632 SysRq on a serial console. 622 SysRq on a serial console. 633 623 634 If unsure, leave an empty string and 624 If unsure, leave an empty string and the option will not be enabled. 635 625 636 config DEBUG_FS 626 config DEBUG_FS 637 bool "Debug Filesystem" 627 bool "Debug Filesystem" 638 help 628 help 639 debugfs is a virtual file system tha 629 debugfs is a virtual file system that kernel developers use to put 640 debugging files into. Enable this o 630 debugging files into. Enable this option to be able to read and 641 write to these files. 631 write to these files. 642 632 643 For detailed documentation on the de 633 For detailed documentation on the debugfs API, see 644 Documentation/filesystems/. 634 Documentation/filesystems/. 645 635 646 If unsure, say N. 636 If unsure, say N. 647 637 648 choice 638 choice 649 prompt "Debugfs default access" 639 prompt "Debugfs default access" 650 depends on DEBUG_FS 640 depends on DEBUG_FS 651 default DEBUG_FS_ALLOW_ALL 641 default DEBUG_FS_ALLOW_ALL 652 help 642 help 653 This selects the default access rest 643 This selects the default access restrictions for debugfs. 654 It can be overridden with kernel com 644 It can be overridden with kernel command line option 655 debugfs=[on,no-mount,off]. The restr 645 debugfs=[on,no-mount,off]. The restrictions apply for API access 656 and filesystem registration. 646 and filesystem registration. 657 647 658 config DEBUG_FS_ALLOW_ALL 648 config DEBUG_FS_ALLOW_ALL 659 bool "Access normal" 649 bool "Access normal" 660 help 650 help 661 No restrictions apply. Both API and 651 No restrictions apply. Both API and filesystem registration 662 is on. This is the normal default op 652 is on. This is the normal default operation. 663 653 664 config DEBUG_FS_DISALLOW_MOUNT 654 config DEBUG_FS_DISALLOW_MOUNT 665 bool "Do not register debugfs as files 655 bool "Do not register debugfs as filesystem" 666 help 656 help 667 The API is open but filesystem is no 657 The API is open but filesystem is not loaded. Clients can still do 668 their work and read with debug tools 658 their work and read with debug tools that do not need 669 debugfs filesystem. 659 debugfs filesystem. 670 660 671 config DEBUG_FS_ALLOW_NONE 661 config DEBUG_FS_ALLOW_NONE 672 bool "No access" 662 bool "No access" 673 help 663 help 674 Access is off. Clients get -PERM whe 664 Access is off. Clients get -PERM when trying to create nodes in 675 debugfs tree and debugfs is not regi 665 debugfs tree and debugfs is not registered as a filesystem. 676 Client can then back-off or continue 666 Client can then back-off or continue without debugfs access. 677 667 678 endchoice 668 endchoice 679 669 680 source "lib/Kconfig.kgdb" 670 source "lib/Kconfig.kgdb" 681 source "lib/Kconfig.ubsan" 671 source "lib/Kconfig.ubsan" 682 source "lib/Kconfig.kcsan" 672 source "lib/Kconfig.kcsan" 683 673 684 endmenu 674 endmenu 685 675 686 menu "Networking Debugging" 676 menu "Networking Debugging" 687 677 688 source "net/Kconfig.debug" 678 source "net/Kconfig.debug" 689 679 690 endmenu # "Networking Debugging" 680 endmenu # "Networking Debugging" 691 681 692 menu "Memory Debugging" 682 menu "Memory Debugging" 693 683 694 source "mm/Kconfig.debug" 684 source "mm/Kconfig.debug" 695 685 696 config DEBUG_OBJECTS 686 config DEBUG_OBJECTS 697 bool "Debug object operations" 687 bool "Debug object operations" 698 depends on DEBUG_KERNEL 688 depends on DEBUG_KERNEL 699 help 689 help 700 If you say Y here, additional code w 690 If you say Y here, additional code will be inserted into the 701 kernel to track the life time of var 691 kernel to track the life time of various objects and validate 702 the operations on those objects. 692 the operations on those objects. 703 693 704 config DEBUG_OBJECTS_SELFTEST 694 config DEBUG_OBJECTS_SELFTEST 705 bool "Debug objects selftest" 695 bool "Debug objects selftest" 706 depends on DEBUG_OBJECTS 696 depends on DEBUG_OBJECTS 707 help 697 help 708 This enables the selftest of the obj 698 This enables the selftest of the object debug code. 709 699 710 config DEBUG_OBJECTS_FREE 700 config DEBUG_OBJECTS_FREE 711 bool "Debug objects in freed memory" 701 bool "Debug objects in freed memory" 712 depends on DEBUG_OBJECTS 702 depends on DEBUG_OBJECTS 713 help 703 help 714 This enables checks whether a k/v fr 704 This enables checks whether a k/v free operation frees an area 715 which contains an object which has n 705 which contains an object which has not been deactivated 716 properly. This can make kmalloc/kfre 706 properly. This can make kmalloc/kfree-intensive workloads 717 much slower. 707 much slower. 718 708 719 config DEBUG_OBJECTS_TIMERS 709 config DEBUG_OBJECTS_TIMERS 720 bool "Debug timer objects" 710 bool "Debug timer objects" 721 depends on DEBUG_OBJECTS 711 depends on DEBUG_OBJECTS 722 help 712 help 723 If you say Y here, additional code w 713 If you say Y here, additional code will be inserted into the 724 timer routines to track the life tim 714 timer routines to track the life time of timer objects and 725 validate the timer operations. 715 validate the timer operations. 726 716 727 config DEBUG_OBJECTS_WORK 717 config DEBUG_OBJECTS_WORK 728 bool "Debug work objects" 718 bool "Debug work objects" 729 depends on DEBUG_OBJECTS 719 depends on DEBUG_OBJECTS 730 help 720 help 731 If you say Y here, additional code w 721 If you say Y here, additional code will be inserted into the 732 work queue routines to track the lif 722 work queue routines to track the life time of work objects and 733 validate the work operations. 723 validate the work operations. 734 724 735 config DEBUG_OBJECTS_RCU_HEAD 725 config DEBUG_OBJECTS_RCU_HEAD 736 bool "Debug RCU callbacks objects" 726 bool "Debug RCU callbacks objects" 737 depends on DEBUG_OBJECTS 727 depends on DEBUG_OBJECTS 738 help 728 help 739 Enable this to turn on debugging of 729 Enable this to turn on debugging of RCU list heads (call_rcu() usage). 740 730 741 config DEBUG_OBJECTS_PERCPU_COUNTER 731 config DEBUG_OBJECTS_PERCPU_COUNTER 742 bool "Debug percpu counter objects" 732 bool "Debug percpu counter objects" 743 depends on DEBUG_OBJECTS 733 depends on DEBUG_OBJECTS 744 help 734 help 745 If you say Y here, additional code w 735 If you say Y here, additional code will be inserted into the 746 percpu counter routines to track the 736 percpu counter routines to track the life time of percpu counter 747 objects and validate the percpu coun 737 objects and validate the percpu counter operations. 748 738 749 config DEBUG_OBJECTS_ENABLE_DEFAULT 739 config DEBUG_OBJECTS_ENABLE_DEFAULT 750 int "debug_objects bootup default valu 740 int "debug_objects bootup default value (0-1)" 751 range 0 1 741 range 0 1 752 default "1" 742 default "1" 753 depends on DEBUG_OBJECTS 743 depends on DEBUG_OBJECTS 754 help 744 help 755 Debug objects boot parameter default 745 Debug objects boot parameter default value 756 746 757 config SHRINKER_DEBUG 747 config SHRINKER_DEBUG 758 bool "Enable shrinker debugging suppor 748 bool "Enable shrinker debugging support" 759 depends on DEBUG_FS 749 depends on DEBUG_FS 760 help 750 help 761 Say Y to enable the shrinker debugfs 751 Say Y to enable the shrinker debugfs interface which provides 762 visibility into the kernel memory sh 752 visibility into the kernel memory shrinkers subsystem. 763 Disable it to avoid an extra memory 753 Disable it to avoid an extra memory footprint. 764 754 765 config DEBUG_STACK_USAGE 755 config DEBUG_STACK_USAGE 766 bool "Stack utilization instrumentatio 756 bool "Stack utilization instrumentation" 767 depends on DEBUG_KERNEL !! 757 depends on DEBUG_KERNEL && !IA64 768 help 758 help 769 Enables the display of the minimum a 759 Enables the display of the minimum amount of free stack which each 770 task has ever had available in the s 760 task has ever had available in the sysrq-T and sysrq-P debug output. 771 Also emits a message to dmesg when a << 772 used more stack space than previousl << 773 761 774 This option will slow down process c 762 This option will slow down process creation somewhat. 775 763 776 config SCHED_STACK_END_CHECK 764 config SCHED_STACK_END_CHECK 777 bool "Detect stack corruption on calls 765 bool "Detect stack corruption on calls to schedule()" 778 depends on DEBUG_KERNEL 766 depends on DEBUG_KERNEL 779 default n 767 default n 780 help 768 help 781 This option checks for a stack overr 769 This option checks for a stack overrun on calls to schedule(). 782 If the stack end location is found t 770 If the stack end location is found to be over written always panic as 783 the content of the corrupted region 771 the content of the corrupted region can no longer be trusted. 784 This is to ensure no erroneous behav 772 This is to ensure no erroneous behaviour occurs which could result in 785 data corruption or a sporadic crash 773 data corruption or a sporadic crash at a later stage once the region 786 is examined. The runtime overhead in 774 is examined. The runtime overhead introduced is minimal. 787 775 788 config ARCH_HAS_DEBUG_VM_PGTABLE 776 config ARCH_HAS_DEBUG_VM_PGTABLE 789 bool 777 bool 790 help 778 help 791 An architecture should select this w 779 An architecture should select this when it can successfully 792 build and run DEBUG_VM_PGTABLE. 780 build and run DEBUG_VM_PGTABLE. 793 781 794 config DEBUG_VM_IRQSOFF 782 config DEBUG_VM_IRQSOFF 795 def_bool DEBUG_VM && !PREEMPT_RT 783 def_bool DEBUG_VM && !PREEMPT_RT 796 784 797 config DEBUG_VM 785 config DEBUG_VM 798 bool "Debug VM" 786 bool "Debug VM" 799 depends on DEBUG_KERNEL 787 depends on DEBUG_KERNEL 800 help 788 help 801 Enable this to turn on extended chec 789 Enable this to turn on extended checks in the virtual-memory system 802 that may impact performance. 790 that may impact performance. 803 791 804 If unsure, say N. 792 If unsure, say N. 805 793 806 config DEBUG_VM_SHOOT_LAZIES 794 config DEBUG_VM_SHOOT_LAZIES 807 bool "Debug MMU_LAZY_TLB_SHOOTDOWN imp 795 bool "Debug MMU_LAZY_TLB_SHOOTDOWN implementation" 808 depends on DEBUG_VM 796 depends on DEBUG_VM 809 depends on MMU_LAZY_TLB_SHOOTDOWN 797 depends on MMU_LAZY_TLB_SHOOTDOWN 810 help 798 help 811 Enable additional IPIs that ensure l 799 Enable additional IPIs that ensure lazy tlb mm references are removed 812 before the mm is freed. 800 before the mm is freed. 813 801 814 If unsure, say N. 802 If unsure, say N. 815 803 816 config DEBUG_VM_MAPLE_TREE 804 config DEBUG_VM_MAPLE_TREE 817 bool "Debug VM maple trees" 805 bool "Debug VM maple trees" 818 depends on DEBUG_VM 806 depends on DEBUG_VM 819 select DEBUG_MAPLE_TREE 807 select DEBUG_MAPLE_TREE 820 help 808 help 821 Enable VM maple tree debugging infor 809 Enable VM maple tree debugging information and extra validations. 822 810 823 If unsure, say N. 811 If unsure, say N. 824 812 825 config DEBUG_VM_RB 813 config DEBUG_VM_RB 826 bool "Debug VM red-black trees" 814 bool "Debug VM red-black trees" 827 depends on DEBUG_VM 815 depends on DEBUG_VM 828 help 816 help 829 Enable VM red-black tree debugging i 817 Enable VM red-black tree debugging information and extra validations. 830 818 831 If unsure, say N. 819 If unsure, say N. 832 820 833 config DEBUG_VM_PGFLAGS 821 config DEBUG_VM_PGFLAGS 834 bool "Debug page-flags operations" 822 bool "Debug page-flags operations" 835 depends on DEBUG_VM 823 depends on DEBUG_VM 836 help 824 help 837 Enables extra validation on page fla 825 Enables extra validation on page flags operations. 838 826 839 If unsure, say N. 827 If unsure, say N. 840 828 841 config DEBUG_VM_PGTABLE 829 config DEBUG_VM_PGTABLE 842 bool "Debug arch page table for semant 830 bool "Debug arch page table for semantics compliance" 843 depends on MMU 831 depends on MMU 844 depends on ARCH_HAS_DEBUG_VM_PGTABLE 832 depends on ARCH_HAS_DEBUG_VM_PGTABLE 845 default y if DEBUG_VM 833 default y if DEBUG_VM 846 help 834 help 847 This option provides a debug method 835 This option provides a debug method which can be used to test 848 architecture page table helper funct 836 architecture page table helper functions on various platforms in 849 verifying if they comply with expect 837 verifying if they comply with expected generic MM semantics. This 850 will help architecture code in makin 838 will help architecture code in making sure that any changes or 851 new additions of these helpers still 839 new additions of these helpers still conform to expected 852 semantics of the generic MM. Platfor 840 semantics of the generic MM. Platforms will have to opt in for 853 this through ARCH_HAS_DEBUG_VM_PGTAB 841 this through ARCH_HAS_DEBUG_VM_PGTABLE. 854 842 855 If unsure, say N. 843 If unsure, say N. 856 844 857 config ARCH_HAS_DEBUG_VIRTUAL 845 config ARCH_HAS_DEBUG_VIRTUAL 858 bool 846 bool 859 847 860 config DEBUG_VIRTUAL 848 config DEBUG_VIRTUAL 861 bool "Debug VM translations" 849 bool "Debug VM translations" 862 depends on DEBUG_KERNEL && ARCH_HAS_DE 850 depends on DEBUG_KERNEL && ARCH_HAS_DEBUG_VIRTUAL 863 help 851 help 864 Enable some costly sanity checks in 852 Enable some costly sanity checks in virtual to page code. This can 865 catch mistakes with virt_to_page() a 853 catch mistakes with virt_to_page() and friends. 866 854 867 If unsure, say N. 855 If unsure, say N. 868 856 869 config DEBUG_NOMMU_REGIONS 857 config DEBUG_NOMMU_REGIONS 870 bool "Debug the global anon/private NO 858 bool "Debug the global anon/private NOMMU mapping region tree" 871 depends on DEBUG_KERNEL && !MMU 859 depends on DEBUG_KERNEL && !MMU 872 help 860 help 873 This option causes the global tree o 861 This option causes the global tree of anonymous and private mapping 874 regions to be regularly checked for 862 regions to be regularly checked for invalid topology. 875 863 876 config DEBUG_MEMORY_INIT 864 config DEBUG_MEMORY_INIT 877 bool "Debug memory initialisation" if 865 bool "Debug memory initialisation" if EXPERT 878 default !EXPERT 866 default !EXPERT 879 help 867 help 880 Enable this for additional checks du 868 Enable this for additional checks during memory initialisation. 881 The sanity checks verify aspects of 869 The sanity checks verify aspects of the VM such as the memory model 882 and other information provided by th 870 and other information provided by the architecture. Verbose 883 information will be printed at KERN_ 871 information will be printed at KERN_DEBUG loglevel depending 884 on the mminit_loglevel= command-line 872 on the mminit_loglevel= command-line option. 885 873 886 If unsure, say Y 874 If unsure, say Y 887 875 888 config MEMORY_NOTIFIER_ERROR_INJECT 876 config MEMORY_NOTIFIER_ERROR_INJECT 889 tristate "Memory hotplug notifier erro 877 tristate "Memory hotplug notifier error injection module" 890 depends on MEMORY_HOTPLUG && NOTIFIER_ 878 depends on MEMORY_HOTPLUG && NOTIFIER_ERROR_INJECTION 891 help 879 help 892 This option provides the ability to 880 This option provides the ability to inject artificial errors to 893 memory hotplug notifier chain callba 881 memory hotplug notifier chain callbacks. It is controlled through 894 debugfs interface under /sys/kernel/ 882 debugfs interface under /sys/kernel/debug/notifier-error-inject/memory 895 883 896 If the notifier call chain should be 884 If the notifier call chain should be failed with some events 897 notified, write the error code to "a 885 notified, write the error code to "actions/<notifier event>/error". 898 886 899 Example: Inject memory hotplug offli 887 Example: Inject memory hotplug offline error (-12 == -ENOMEM) 900 888 901 # cd /sys/kernel/debug/notifier-erro 889 # cd /sys/kernel/debug/notifier-error-inject/memory 902 # echo -12 > actions/MEM_GOING_OFFLI 890 # echo -12 > actions/MEM_GOING_OFFLINE/error 903 # echo offline > /sys/devices/system 891 # echo offline > /sys/devices/system/memory/memoryXXX/state 904 bash: echo: write error: Cannot allo 892 bash: echo: write error: Cannot allocate memory 905 893 906 To compile this code as a module, ch 894 To compile this code as a module, choose M here: the module will 907 be called memory-notifier-error-inje 895 be called memory-notifier-error-inject. 908 896 909 If unsure, say N. 897 If unsure, say N. 910 898 911 config DEBUG_PER_CPU_MAPS 899 config DEBUG_PER_CPU_MAPS 912 bool "Debug access to per_cpu maps" 900 bool "Debug access to per_cpu maps" 913 depends on DEBUG_KERNEL 901 depends on DEBUG_KERNEL 914 depends on SMP 902 depends on SMP 915 help 903 help 916 Say Y to verify that the per_cpu map 904 Say Y to verify that the per_cpu map being accessed has 917 been set up. This adds a fair amount 905 been set up. This adds a fair amount of code to kernel memory 918 and decreases performance. 906 and decreases performance. 919 907 920 Say N if unsure. 908 Say N if unsure. 921 909 922 config DEBUG_KMAP_LOCAL 910 config DEBUG_KMAP_LOCAL 923 bool "Debug kmap_local temporary mappi 911 bool "Debug kmap_local temporary mappings" 924 depends on DEBUG_KERNEL && KMAP_LOCAL 912 depends on DEBUG_KERNEL && KMAP_LOCAL 925 help 913 help 926 This option enables additional error 914 This option enables additional error checking for the kmap_local 927 infrastructure. Disable for product 915 infrastructure. Disable for production use. 928 916 929 config ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP 917 config ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP 930 bool 918 bool 931 919 932 config DEBUG_KMAP_LOCAL_FORCE_MAP 920 config DEBUG_KMAP_LOCAL_FORCE_MAP 933 bool "Enforce kmap_local temporary map 921 bool "Enforce kmap_local temporary mappings" 934 depends on DEBUG_KERNEL && ARCH_SUPPOR 922 depends on DEBUG_KERNEL && ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP 935 select KMAP_LOCAL 923 select KMAP_LOCAL 936 select DEBUG_KMAP_LOCAL 924 select DEBUG_KMAP_LOCAL 937 help 925 help 938 This option enforces temporary mappi 926 This option enforces temporary mappings through the kmap_local 939 mechanism for non-highmem pages and 927 mechanism for non-highmem pages and on non-highmem systems. 940 Disable this for production systems! 928 Disable this for production systems! 941 929 942 config DEBUG_HIGHMEM 930 config DEBUG_HIGHMEM 943 bool "Highmem debugging" 931 bool "Highmem debugging" 944 depends on DEBUG_KERNEL && HIGHMEM 932 depends on DEBUG_KERNEL && HIGHMEM 945 select DEBUG_KMAP_LOCAL_FORCE_MAP if A 933 select DEBUG_KMAP_LOCAL_FORCE_MAP if ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP 946 select DEBUG_KMAP_LOCAL 934 select DEBUG_KMAP_LOCAL 947 help 935 help 948 This option enables additional error 936 This option enables additional error checking for high memory 949 systems. Disable for production sys 937 systems. Disable for production systems. 950 938 951 config HAVE_DEBUG_STACKOVERFLOW 939 config HAVE_DEBUG_STACKOVERFLOW 952 bool 940 bool 953 941 954 config DEBUG_STACKOVERFLOW 942 config DEBUG_STACKOVERFLOW 955 bool "Check for stack overflows" 943 bool "Check for stack overflows" 956 depends on DEBUG_KERNEL && HAVE_DEBUG_ 944 depends on DEBUG_KERNEL && HAVE_DEBUG_STACKOVERFLOW 957 help 945 help 958 Say Y here if you want to check for 946 Say Y here if you want to check for overflows of kernel, IRQ 959 and exception stacks (if your archit 947 and exception stacks (if your architecture uses them). This 960 option will show detailed messages i 948 option will show detailed messages if free stack space drops 961 below a certain limit. 949 below a certain limit. 962 950 963 These kinds of bugs usually occur wh 951 These kinds of bugs usually occur when call-chains in the 964 kernel get too deep, especially when 952 kernel get too deep, especially when interrupts are 965 involved. 953 involved. 966 954 967 Use this in cases where you see appa 955 Use this in cases where you see apparently random memory 968 corruption, especially if it appears 956 corruption, especially if it appears in 'struct thread_info' 969 957 970 If in doubt, say "N". 958 If in doubt, say "N". 971 959 972 config CODE_TAGGING << 973 bool << 974 select KALLSYMS << 975 << 976 config MEM_ALLOC_PROFILING << 977 bool "Enable memory allocation profili << 978 default n << 979 depends on PROC_FS << 980 depends on !DEBUG_FORCE_WEAK_PER_CPU << 981 select CODE_TAGGING << 982 select PAGE_EXTENSION << 983 select SLAB_OBJ_EXT << 984 help << 985 Track allocation source code and rec << 986 initiated at that code location. The << 987 memory leaks with a low performance << 988 << 989 config MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT << 990 bool "Enable memory allocation profili << 991 default y << 992 depends on MEM_ALLOC_PROFILING << 993 << 994 config MEM_ALLOC_PROFILING_DEBUG << 995 bool "Memory allocation profiler debug << 996 default n << 997 depends on MEM_ALLOC_PROFILING << 998 select MEM_ALLOC_PROFILING_ENABLED_BY_ << 999 help << 1000 Adds warnings with helpful error me << 1001 profiling. << 1002 << 1003 source "lib/Kconfig.kasan" 960 source "lib/Kconfig.kasan" 1004 source "lib/Kconfig.kfence" 961 source "lib/Kconfig.kfence" 1005 source "lib/Kconfig.kmsan" 962 source "lib/Kconfig.kmsan" 1006 963 1007 endmenu # "Memory Debugging" 964 endmenu # "Memory Debugging" 1008 965 1009 config DEBUG_SHIRQ 966 config DEBUG_SHIRQ 1010 bool "Debug shared IRQ handlers" 967 bool "Debug shared IRQ handlers" 1011 depends on DEBUG_KERNEL 968 depends on DEBUG_KERNEL 1012 help 969 help 1013 Enable this to generate a spurious 970 Enable this to generate a spurious interrupt just before a shared 1014 interrupt handler is deregistered ( 971 interrupt handler is deregistered (generating one when registering 1015 is currently disabled). Drivers nee 972 is currently disabled). Drivers need to handle this correctly. Some 1016 don't and need to be caught. 973 don't and need to be caught. 1017 974 1018 menu "Debug Oops, Lockups and Hangs" 975 menu "Debug Oops, Lockups and Hangs" 1019 976 1020 config PANIC_ON_OOPS 977 config PANIC_ON_OOPS 1021 bool "Panic on Oops" 978 bool "Panic on Oops" 1022 help 979 help 1023 Say Y here to enable the kernel to 980 Say Y here to enable the kernel to panic when it oopses. This 1024 has the same effect as setting oops 981 has the same effect as setting oops=panic on the kernel command 1025 line. 982 line. 1026 983 1027 This feature is useful to ensure th 984 This feature is useful to ensure that the kernel does not do 1028 anything erroneous after an oops wh 985 anything erroneous after an oops which could result in data 1029 corruption or other issues. 986 corruption or other issues. 1030 987 1031 Say N if unsure. 988 Say N if unsure. 1032 989 1033 config PANIC_ON_OOPS_VALUE 990 config PANIC_ON_OOPS_VALUE 1034 int 991 int 1035 range 0 1 992 range 0 1 1036 default 0 if !PANIC_ON_OOPS 993 default 0 if !PANIC_ON_OOPS 1037 default 1 if PANIC_ON_OOPS 994 default 1 if PANIC_ON_OOPS 1038 995 1039 config PANIC_TIMEOUT 996 config PANIC_TIMEOUT 1040 int "panic timeout" 997 int "panic timeout" 1041 default 0 998 default 0 1042 help 999 help 1043 Set the timeout value (in seconds) 1000 Set the timeout value (in seconds) until a reboot occurs when 1044 the kernel panics. If n = 0, then w 1001 the kernel panics. If n = 0, then we wait forever. A timeout 1045 value n > 0 will wait n seconds bef 1002 value n > 0 will wait n seconds before rebooting, while a timeout 1046 value n < 0 will reboot immediately !! 1003 value n < 0 will reboot immediately. 1047 with the kernel command line option << 1048 /proc/sys/kernel/panic. << 1049 1004 1050 config LOCKUP_DETECTOR 1005 config LOCKUP_DETECTOR 1051 bool 1006 bool 1052 1007 1053 config SOFTLOCKUP_DETECTOR 1008 config SOFTLOCKUP_DETECTOR 1054 bool "Detect Soft Lockups" 1009 bool "Detect Soft Lockups" 1055 depends on DEBUG_KERNEL && !S390 1010 depends on DEBUG_KERNEL && !S390 1056 select LOCKUP_DETECTOR 1011 select LOCKUP_DETECTOR 1057 help 1012 help 1058 Say Y here to enable the kernel to 1013 Say Y here to enable the kernel to act as a watchdog to detect 1059 soft lockups. 1014 soft lockups. 1060 1015 1061 Softlockups are bugs that cause the 1016 Softlockups are bugs that cause the kernel to loop in kernel 1062 mode for more than 20 seconds, with 1017 mode for more than 20 seconds, without giving other tasks a 1063 chance to run. The current stack t 1018 chance to run. The current stack trace is displayed upon 1064 detection and the system will stay 1019 detection and the system will stay locked up. 1065 1020 1066 config SOFTLOCKUP_DETECTOR_INTR_STORM << 1067 bool "Detect Interrupt Storm in Soft << 1068 depends on SOFTLOCKUP_DETECTOR && IRQ << 1069 select GENERIC_IRQ_STAT_SNAPSHOT << 1070 default y if NR_CPUS <= 128 << 1071 help << 1072 Say Y here to enable the kernel to << 1073 during "soft lockups". << 1074 << 1075 "soft lockups" can be caused by a v << 1076 caused by an interrupt storm, then << 1077 be on the callstack. To detect this << 1078 the CPU stats and the interrupt cou << 1079 << 1080 config BOOTPARAM_SOFTLOCKUP_PANIC 1021 config BOOTPARAM_SOFTLOCKUP_PANIC 1081 bool "Panic (Reboot) On Soft Lockups" 1022 bool "Panic (Reboot) On Soft Lockups" 1082 depends on SOFTLOCKUP_DETECTOR 1023 depends on SOFTLOCKUP_DETECTOR 1083 help 1024 help 1084 Say Y here to enable the kernel to 1025 Say Y here to enable the kernel to panic on "soft lockups", 1085 which are bugs that cause the kerne 1026 which are bugs that cause the kernel to loop in kernel 1086 mode for more than 20 seconds (conf 1027 mode for more than 20 seconds (configurable using the watchdog_thresh 1087 sysctl), without giving other tasks 1028 sysctl), without giving other tasks a chance to run. 1088 1029 1089 The panic can be used in combinatio 1030 The panic can be used in combination with panic_timeout, 1090 to cause the system to reboot autom 1031 to cause the system to reboot automatically after a 1091 lockup has been detected. This feat 1032 lockup has been detected. This feature is useful for 1092 high-availability systems that have 1033 high-availability systems that have uptime guarantees and 1093 where a lockup must be resolved ASA 1034 where a lockup must be resolved ASAP. 1094 1035 1095 Say N if unsure. 1036 Say N if unsure. 1096 1037 1097 config HAVE_HARDLOCKUP_DETECTOR_BUDDY 1038 config HAVE_HARDLOCKUP_DETECTOR_BUDDY 1098 bool 1039 bool 1099 depends on SMP 1040 depends on SMP 1100 default y 1041 default y 1101 1042 1102 # 1043 # 1103 # Global switch whether to build a hardlockup 1044 # Global switch whether to build a hardlockup detector at all. It is available 1104 # only when the architecture supports at leas 1045 # only when the architecture supports at least one implementation. There are 1105 # two exceptions. The hardlockup detector is 1046 # two exceptions. The hardlockup detector is never enabled on: 1106 # 1047 # 1107 # s390: it reported many false positive 1048 # s390: it reported many false positives there 1108 # 1049 # 1109 # sparc64: has a custom implementation 1050 # sparc64: has a custom implementation which is not using the common 1110 # hardlockup command line optio 1051 # hardlockup command line options and sysctl interface. 1111 # 1052 # 1112 config HARDLOCKUP_DETECTOR 1053 config HARDLOCKUP_DETECTOR 1113 bool "Detect Hard Lockups" 1054 bool "Detect Hard Lockups" 1114 depends on DEBUG_KERNEL && !S390 && ! 1055 depends on DEBUG_KERNEL && !S390 && !HARDLOCKUP_DETECTOR_SPARC64 1115 depends on HAVE_HARDLOCKUP_DETECTOR_P 1056 depends on HAVE_HARDLOCKUP_DETECTOR_PERF || HAVE_HARDLOCKUP_DETECTOR_BUDDY || HAVE_HARDLOCKUP_DETECTOR_ARCH 1116 imply HARDLOCKUP_DETECTOR_PERF 1057 imply HARDLOCKUP_DETECTOR_PERF 1117 imply HARDLOCKUP_DETECTOR_BUDDY 1058 imply HARDLOCKUP_DETECTOR_BUDDY 1118 imply HARDLOCKUP_DETECTOR_ARCH 1059 imply HARDLOCKUP_DETECTOR_ARCH 1119 select LOCKUP_DETECTOR 1060 select LOCKUP_DETECTOR 1120 1061 1121 help 1062 help 1122 Say Y here to enable the kernel to 1063 Say Y here to enable the kernel to act as a watchdog to detect 1123 hard lockups. 1064 hard lockups. 1124 1065 1125 Hardlockups are bugs that cause the 1066 Hardlockups are bugs that cause the CPU to loop in kernel mode 1126 for more than 10 seconds, without l 1067 for more than 10 seconds, without letting other interrupts have a 1127 chance to run. The current stack t 1068 chance to run. The current stack trace is displayed upon detection 1128 and the system will stay locked up. 1069 and the system will stay locked up. 1129 1070 1130 # 1071 # 1131 # Note that arch-specific variants are always 1072 # Note that arch-specific variants are always preferred. 1132 # 1073 # 1133 config HARDLOCKUP_DETECTOR_PREFER_BUDDY 1074 config HARDLOCKUP_DETECTOR_PREFER_BUDDY 1134 bool "Prefer the buddy CPU hardlockup 1075 bool "Prefer the buddy CPU hardlockup detector" 1135 depends on HARDLOCKUP_DETECTOR 1076 depends on HARDLOCKUP_DETECTOR 1136 depends on HAVE_HARDLOCKUP_DETECTOR_P 1077 depends on HAVE_HARDLOCKUP_DETECTOR_PERF && HAVE_HARDLOCKUP_DETECTOR_BUDDY 1137 depends on !HAVE_HARDLOCKUP_DETECTOR_ 1078 depends on !HAVE_HARDLOCKUP_DETECTOR_ARCH 1138 help 1079 help 1139 Say Y here to prefer the buddy hard 1080 Say Y here to prefer the buddy hardlockup detector over the perf one. 1140 1081 1141 With the buddy detector, each CPU u 1082 With the buddy detector, each CPU uses its softlockup hrtimer 1142 to check that the next CPU is proce 1083 to check that the next CPU is processing hrtimer interrupts by 1143 verifying that a counter is increas 1084 verifying that a counter is increasing. 1144 1085 1145 This hardlockup detector is useful 1086 This hardlockup detector is useful on systems that don't have 1146 an arch-specific hardlockup detecto 1087 an arch-specific hardlockup detector or if resources needed 1147 for the hardlockup detector are bet 1088 for the hardlockup detector are better used for other things. 1148 1089 1149 config HARDLOCKUP_DETECTOR_PERF 1090 config HARDLOCKUP_DETECTOR_PERF 1150 bool 1091 bool 1151 depends on HARDLOCKUP_DETECTOR 1092 depends on HARDLOCKUP_DETECTOR 1152 depends on HAVE_HARDLOCKUP_DETECTOR_P 1093 depends on HAVE_HARDLOCKUP_DETECTOR_PERF && !HARDLOCKUP_DETECTOR_PREFER_BUDDY 1153 depends on !HAVE_HARDLOCKUP_DETECTOR_ 1094 depends on !HAVE_HARDLOCKUP_DETECTOR_ARCH 1154 select HARDLOCKUP_DETECTOR_COUNTS_HRT 1095 select HARDLOCKUP_DETECTOR_COUNTS_HRTIMER 1155 1096 1156 config HARDLOCKUP_DETECTOR_BUDDY 1097 config HARDLOCKUP_DETECTOR_BUDDY 1157 bool 1098 bool 1158 depends on HARDLOCKUP_DETECTOR 1099 depends on HARDLOCKUP_DETECTOR 1159 depends on HAVE_HARDLOCKUP_DETECTOR_B 1100 depends on HAVE_HARDLOCKUP_DETECTOR_BUDDY 1160 depends on !HAVE_HARDLOCKUP_DETECTOR_ 1101 depends on !HAVE_HARDLOCKUP_DETECTOR_PERF || HARDLOCKUP_DETECTOR_PREFER_BUDDY 1161 depends on !HAVE_HARDLOCKUP_DETECTOR_ 1102 depends on !HAVE_HARDLOCKUP_DETECTOR_ARCH 1162 select HARDLOCKUP_DETECTOR_COUNTS_HRT 1103 select HARDLOCKUP_DETECTOR_COUNTS_HRTIMER 1163 1104 1164 config HARDLOCKUP_DETECTOR_ARCH 1105 config HARDLOCKUP_DETECTOR_ARCH 1165 bool 1106 bool 1166 depends on HARDLOCKUP_DETECTOR 1107 depends on HARDLOCKUP_DETECTOR 1167 depends on HAVE_HARDLOCKUP_DETECTOR_A 1108 depends on HAVE_HARDLOCKUP_DETECTOR_ARCH 1168 help 1109 help 1169 The arch-specific implementation of 1110 The arch-specific implementation of the hardlockup detector will 1170 be used. 1111 be used. 1171 1112 1172 # 1113 # 1173 # Both the "perf" and "buddy" hardlockup dete 1114 # Both the "perf" and "buddy" hardlockup detectors count hrtimer 1174 # interrupts. This config enables functions m 1115 # interrupts. This config enables functions managing this common code. 1175 # 1116 # 1176 config HARDLOCKUP_DETECTOR_COUNTS_HRTIMER 1117 config HARDLOCKUP_DETECTOR_COUNTS_HRTIMER 1177 bool 1118 bool 1178 select SOFTLOCKUP_DETECTOR 1119 select SOFTLOCKUP_DETECTOR 1179 1120 1180 # 1121 # 1181 # Enables a timestamp based low pass filter t 1122 # Enables a timestamp based low pass filter to compensate for perf based 1182 # hard lockup detection which runs too fast d 1123 # hard lockup detection which runs too fast due to turbo modes. 1183 # 1124 # 1184 config HARDLOCKUP_CHECK_TIMESTAMP 1125 config HARDLOCKUP_CHECK_TIMESTAMP 1185 bool 1126 bool 1186 1127 1187 config BOOTPARAM_HARDLOCKUP_PANIC 1128 config BOOTPARAM_HARDLOCKUP_PANIC 1188 bool "Panic (Reboot) On Hard Lockups" 1129 bool "Panic (Reboot) On Hard Lockups" 1189 depends on HARDLOCKUP_DETECTOR 1130 depends on HARDLOCKUP_DETECTOR 1190 help 1131 help 1191 Say Y here to enable the kernel to 1132 Say Y here to enable the kernel to panic on "hard lockups", 1192 which are bugs that cause the kerne 1133 which are bugs that cause the kernel to loop in kernel 1193 mode with interrupts disabled for m 1134 mode with interrupts disabled for more than 10 seconds (configurable 1194 using the watchdog_thresh sysctl). 1135 using the watchdog_thresh sysctl). 1195 1136 1196 Say N if unsure. 1137 Say N if unsure. 1197 1138 1198 config DETECT_HUNG_TASK 1139 config DETECT_HUNG_TASK 1199 bool "Detect Hung Tasks" 1140 bool "Detect Hung Tasks" 1200 depends on DEBUG_KERNEL 1141 depends on DEBUG_KERNEL 1201 default SOFTLOCKUP_DETECTOR 1142 default SOFTLOCKUP_DETECTOR 1202 help 1143 help 1203 Say Y here to enable the kernel to 1144 Say Y here to enable the kernel to detect "hung tasks", 1204 which are bugs that cause the task 1145 which are bugs that cause the task to be stuck in 1205 uninterruptible "D" state indefinit 1146 uninterruptible "D" state indefinitely. 1206 1147 1207 When a hung task is detected, the k 1148 When a hung task is detected, the kernel will print the 1208 current stack trace (which you shou 1149 current stack trace (which you should report), but the 1209 task will stay in uninterruptible s 1150 task will stay in uninterruptible state. If lockdep is 1210 enabled then all held locks will al 1151 enabled then all held locks will also be reported. This 1211 feature has negligible overhead. 1152 feature has negligible overhead. 1212 1153 1213 config DEFAULT_HUNG_TASK_TIMEOUT 1154 config DEFAULT_HUNG_TASK_TIMEOUT 1214 int "Default timeout for hung task de 1155 int "Default timeout for hung task detection (in seconds)" 1215 depends on DETECT_HUNG_TASK 1156 depends on DETECT_HUNG_TASK 1216 default 120 1157 default 120 1217 help 1158 help 1218 This option controls the default ti 1159 This option controls the default timeout (in seconds) used 1219 to determine when a task has become 1160 to determine when a task has become non-responsive and should 1220 be considered hung. 1161 be considered hung. 1221 1162 1222 It can be adjusted at runtime via t 1163 It can be adjusted at runtime via the kernel.hung_task_timeout_secs 1223 sysctl or by writing a value to 1164 sysctl or by writing a value to 1224 /proc/sys/kernel/hung_task_timeout_ 1165 /proc/sys/kernel/hung_task_timeout_secs. 1225 1166 1226 A timeout of 0 disables the check. 1167 A timeout of 0 disables the check. The default is two minutes. 1227 Keeping the default should be fine 1168 Keeping the default should be fine in most cases. 1228 1169 1229 config BOOTPARAM_HUNG_TASK_PANIC 1170 config BOOTPARAM_HUNG_TASK_PANIC 1230 bool "Panic (Reboot) On Hung Tasks" 1171 bool "Panic (Reboot) On Hung Tasks" 1231 depends on DETECT_HUNG_TASK 1172 depends on DETECT_HUNG_TASK 1232 help 1173 help 1233 Say Y here to enable the kernel to 1174 Say Y here to enable the kernel to panic on "hung tasks", 1234 which are bugs that cause the kerne 1175 which are bugs that cause the kernel to leave a task stuck 1235 in uninterruptible "D" state. 1176 in uninterruptible "D" state. 1236 1177 1237 The panic can be used in combinatio 1178 The panic can be used in combination with panic_timeout, 1238 to cause the system to reboot autom 1179 to cause the system to reboot automatically after a 1239 hung task has been detected. This f 1180 hung task has been detected. This feature is useful for 1240 high-availability systems that have 1181 high-availability systems that have uptime guarantees and 1241 where a hung tasks must be resolved 1182 where a hung tasks must be resolved ASAP. 1242 1183 1243 Say N if unsure. 1184 Say N if unsure. 1244 1185 1245 config WQ_WATCHDOG 1186 config WQ_WATCHDOG 1246 bool "Detect Workqueue Stalls" 1187 bool "Detect Workqueue Stalls" 1247 depends on DEBUG_KERNEL 1188 depends on DEBUG_KERNEL 1248 help 1189 help 1249 Say Y here to enable stall detectio 1190 Say Y here to enable stall detection on workqueues. If a 1250 worker pool doesn't make forward pr 1191 worker pool doesn't make forward progress on a pending work 1251 item for over a given amount of tim 1192 item for over a given amount of time, 30s by default, a 1252 warning message is printed along wi 1193 warning message is printed along with dump of workqueue 1253 state. This can be configured thro 1194 state. This can be configured through kernel parameter 1254 "workqueue.watchdog_thresh" and its 1195 "workqueue.watchdog_thresh" and its sysfs counterpart. 1255 1196 1256 config WQ_CPU_INTENSIVE_REPORT 1197 config WQ_CPU_INTENSIVE_REPORT 1257 bool "Report per-cpu work items which 1198 bool "Report per-cpu work items which hog CPU for too long" 1258 depends on DEBUG_KERNEL 1199 depends on DEBUG_KERNEL 1259 help 1200 help 1260 Say Y here to enable reporting of c 1201 Say Y here to enable reporting of concurrency-managed per-cpu work 1261 items that hog CPUs for longer than 1202 items that hog CPUs for longer than 1262 workqueue.cpu_intensive_thresh_us. 1203 workqueue.cpu_intensive_thresh_us. Workqueue automatically 1263 detects and excludes them from conc 1204 detects and excludes them from concurrency management to prevent 1264 them from stalling other per-cpu wo 1205 them from stalling other per-cpu work items. Occassional 1265 triggering may not necessarily indi 1206 triggering may not necessarily indicate a problem. Repeated 1266 triggering likely indicates that th 1207 triggering likely indicates that the work item should be switched 1267 to use an unbound workqueue. 1208 to use an unbound workqueue. 1268 1209 1269 config TEST_LOCKUP 1210 config TEST_LOCKUP 1270 tristate "Test module to generate loc 1211 tristate "Test module to generate lockups" 1271 depends on m 1212 depends on m 1272 help 1213 help 1273 This builds the "test_lockup" modul 1214 This builds the "test_lockup" module that helps to make sure 1274 that watchdogs and lockup detectors 1215 that watchdogs and lockup detectors are working properly. 1275 1216 1276 Depending on module parameters it c 1217 Depending on module parameters it could emulate soft or hard 1277 lockup, "hung task", or locking arb 1218 lockup, "hung task", or locking arbitrary lock for a long time. 1278 Also it could generate series of lo 1219 Also it could generate series of lockups with cooling-down periods. 1279 1220 1280 If unsure, say N. 1221 If unsure, say N. 1281 1222 1282 endmenu # "Debug lockups and hangs" 1223 endmenu # "Debug lockups and hangs" 1283 1224 1284 menu "Scheduler Debugging" 1225 menu "Scheduler Debugging" 1285 1226 1286 config SCHED_DEBUG 1227 config SCHED_DEBUG 1287 bool "Collect scheduler debugging inf 1228 bool "Collect scheduler debugging info" 1288 depends on DEBUG_KERNEL && DEBUG_FS 1229 depends on DEBUG_KERNEL && DEBUG_FS 1289 default y 1230 default y 1290 help 1231 help 1291 If you say Y here, the /sys/kernel/ 1232 If you say Y here, the /sys/kernel/debug/sched file will be provided 1292 that can help debug the scheduler. 1233 that can help debug the scheduler. The runtime overhead of this 1293 option is minimal. 1234 option is minimal. 1294 1235 1295 config SCHED_INFO 1236 config SCHED_INFO 1296 bool 1237 bool 1297 default n 1238 default n 1298 1239 1299 config SCHEDSTATS 1240 config SCHEDSTATS 1300 bool "Collect scheduler statistics" 1241 bool "Collect scheduler statistics" 1301 depends on PROC_FS !! 1242 depends on DEBUG_KERNEL && PROC_FS 1302 select SCHED_INFO 1243 select SCHED_INFO 1303 help 1244 help 1304 If you say Y here, additional code 1245 If you say Y here, additional code will be inserted into the 1305 scheduler and related routines to c 1246 scheduler and related routines to collect statistics about 1306 scheduler behavior and provide them 1247 scheduler behavior and provide them in /proc/schedstat. These 1307 stats may be useful for both tuning 1248 stats may be useful for both tuning and debugging the scheduler 1308 If you aren't debugging the schedul 1249 If you aren't debugging the scheduler or trying to tune a specific 1309 application, you can say N to avoid 1250 application, you can say N to avoid the very slight overhead 1310 this adds. 1251 this adds. 1311 1252 1312 endmenu 1253 endmenu 1313 1254 1314 config DEBUG_TIMEKEEPING 1255 config DEBUG_TIMEKEEPING 1315 bool "Enable extra timekeeping sanity 1256 bool "Enable extra timekeeping sanity checking" 1316 help 1257 help 1317 This option will enable additional 1258 This option will enable additional timekeeping sanity checks 1318 which may be helpful when diagnosin 1259 which may be helpful when diagnosing issues where timekeeping 1319 problems are suspected. 1260 problems are suspected. 1320 1261 1321 This may include checks in the time 1262 This may include checks in the timekeeping hotpaths, so this 1322 option may have a (very small) perf 1263 option may have a (very small) performance impact to some 1323 workloads. 1264 workloads. 1324 1265 1325 If unsure, say N. 1266 If unsure, say N. 1326 1267 1327 config DEBUG_PREEMPT 1268 config DEBUG_PREEMPT 1328 bool "Debug preemptible kernel" 1269 bool "Debug preemptible kernel" 1329 depends on DEBUG_KERNEL && PREEMPTION 1270 depends on DEBUG_KERNEL && PREEMPTION && TRACE_IRQFLAGS_SUPPORT 1330 help 1271 help 1331 If you say Y here then the kernel w 1272 If you say Y here then the kernel will use a debug variant of the 1332 commonly used smp_processor_id() fu 1273 commonly used smp_processor_id() function and will print warnings 1333 if kernel code uses it in a preempt 1274 if kernel code uses it in a preemption-unsafe way. Also, the kernel 1334 will detect preemption count underf 1275 will detect preemption count underflows. 1335 1276 1336 This option has potential to introd 1277 This option has potential to introduce high runtime overhead, 1337 depending on workload as it trigger 1278 depending on workload as it triggers debugging routines for each 1338 this_cpu operation. It should only 1279 this_cpu operation. It should only be used for debugging purposes. 1339 1280 1340 menu "Lock Debugging (spinlocks, mutexes, etc 1281 menu "Lock Debugging (spinlocks, mutexes, etc...)" 1341 1282 1342 config LOCK_DEBUGGING_SUPPORT 1283 config LOCK_DEBUGGING_SUPPORT 1343 bool 1284 bool 1344 depends on TRACE_IRQFLAGS_SUPPORT && 1285 depends on TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT 1345 default y 1286 default y 1346 1287 1347 config PROVE_LOCKING 1288 config PROVE_LOCKING 1348 bool "Lock debugging: prove locking c 1289 bool "Lock debugging: prove locking correctness" 1349 depends on DEBUG_KERNEL && LOCK_DEBUG 1290 depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT 1350 select LOCKDEP 1291 select LOCKDEP 1351 select DEBUG_SPINLOCK 1292 select DEBUG_SPINLOCK 1352 select DEBUG_MUTEXES if !PREEMPT_RT 1293 select DEBUG_MUTEXES if !PREEMPT_RT 1353 select DEBUG_RT_MUTEXES if RT_MUTEXES 1294 select DEBUG_RT_MUTEXES if RT_MUTEXES 1354 select DEBUG_RWSEMS if !PREEMPT_RT !! 1295 select DEBUG_RWSEMS 1355 select DEBUG_WW_MUTEX_SLOWPATH 1296 select DEBUG_WW_MUTEX_SLOWPATH 1356 select DEBUG_LOCK_ALLOC 1297 select DEBUG_LOCK_ALLOC 1357 select PREEMPT_COUNT if !ARCH_NO_PREE 1298 select PREEMPT_COUNT if !ARCH_NO_PREEMPT 1358 select TRACE_IRQFLAGS 1299 select TRACE_IRQFLAGS 1359 default n 1300 default n 1360 help 1301 help 1361 This feature enables the kernel to p 1302 This feature enables the kernel to prove that all locking 1362 that occurs in the kernel runtime is 1303 that occurs in the kernel runtime is mathematically 1363 correct: that under no circumstance 1304 correct: that under no circumstance could an arbitrary (and 1364 not yet triggered) combination of ob 1305 not yet triggered) combination of observed locking 1365 sequences (on an arbitrary number of 1306 sequences (on an arbitrary number of CPUs, running an 1366 arbitrary number of tasks and interr 1307 arbitrary number of tasks and interrupt contexts) cause a 1367 deadlock. 1308 deadlock. 1368 1309 1369 In short, this feature enables the k 1310 In short, this feature enables the kernel to report locking 1370 related deadlocks before they actual 1311 related deadlocks before they actually occur. 1371 1312 1372 The proof does not depend on how har 1313 The proof does not depend on how hard and complex a 1373 deadlock scenario would be to trigge 1314 deadlock scenario would be to trigger: how many 1374 participant CPUs, tasks and irq-cont 1315 participant CPUs, tasks and irq-contexts would be needed 1375 for it to trigger. The proof also do 1316 for it to trigger. The proof also does not depend on 1376 timing: if a race and a resulting de 1317 timing: if a race and a resulting deadlock is possible 1377 theoretically (no matter how unlikel 1318 theoretically (no matter how unlikely the race scenario 1378 is), it will be proven so and will i 1319 is), it will be proven so and will immediately be 1379 reported by the kernel (once the eve 1320 reported by the kernel (once the event is observed that 1380 makes the deadlock theoretically pos 1321 makes the deadlock theoretically possible). 1381 1322 1382 If a deadlock is impossible (i.e. th 1323 If a deadlock is impossible (i.e. the locking rules, as 1383 observed by the kernel, are mathemat 1324 observed by the kernel, are mathematically correct), the 1384 kernel reports nothing. 1325 kernel reports nothing. 1385 1326 1386 NOTE: this feature can also be enabl 1327 NOTE: this feature can also be enabled for rwlocks, mutexes 1387 and rwsems - in which case all depen 1328 and rwsems - in which case all dependencies between these 1388 different locking variants are obser 1329 different locking variants are observed and mapped too, and 1389 the proof of observed correctness is 1330 the proof of observed correctness is also maintained for an 1390 arbitrary combination of these separ 1331 arbitrary combination of these separate locking variants. 1391 1332 1392 For more details, see Documentation/ 1333 For more details, see Documentation/locking/lockdep-design.rst. 1393 1334 1394 config PROVE_RAW_LOCK_NESTING 1335 config PROVE_RAW_LOCK_NESTING 1395 bool "Enable raw_spinlock - spinlock 1336 bool "Enable raw_spinlock - spinlock nesting checks" 1396 depends on PROVE_LOCKING 1337 depends on PROVE_LOCKING 1397 default n 1338 default n 1398 help 1339 help 1399 Enable the raw_spinlock vs. spinlock 1340 Enable the raw_spinlock vs. spinlock nesting checks which ensure 1400 that the lock nesting rules for PREE 1341 that the lock nesting rules for PREEMPT_RT enabled kernels are 1401 not violated. 1342 not violated. 1402 1343 1403 NOTE: There are known nesting proble 1344 NOTE: There are known nesting problems. So if you enable this 1404 option expect lockdep splats until t 1345 option expect lockdep splats until these problems have been fully 1405 addressed which is work in progress. 1346 addressed which is work in progress. This config switch allows to 1406 identify and analyze these problems. 1347 identify and analyze these problems. It will be removed and the 1407 check permanently enabled once the m 1348 check permanently enabled once the main issues have been fixed. 1408 1349 1409 If unsure, select N. 1350 If unsure, select N. 1410 1351 1411 config LOCK_STAT 1352 config LOCK_STAT 1412 bool "Lock usage statistics" 1353 bool "Lock usage statistics" 1413 depends on DEBUG_KERNEL && LOCK_DEBUG 1354 depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT 1414 select LOCKDEP 1355 select LOCKDEP 1415 select DEBUG_SPINLOCK 1356 select DEBUG_SPINLOCK 1416 select DEBUG_MUTEXES if !PREEMPT_RT 1357 select DEBUG_MUTEXES if !PREEMPT_RT 1417 select DEBUG_RT_MUTEXES if RT_MUTEXES 1358 select DEBUG_RT_MUTEXES if RT_MUTEXES 1418 select DEBUG_LOCK_ALLOC 1359 select DEBUG_LOCK_ALLOC 1419 default n 1360 default n 1420 help 1361 help 1421 This feature enables tracking lock c 1362 This feature enables tracking lock contention points 1422 1363 1423 For more details, see Documentation/ 1364 For more details, see Documentation/locking/lockstat.rst 1424 1365 1425 This also enables lock events requir 1366 This also enables lock events required by "perf lock", 1426 subcommand of perf. 1367 subcommand of perf. 1427 If you want to use "perf lock", you 1368 If you want to use "perf lock", you also need to turn on 1428 CONFIG_EVENT_TRACING. 1369 CONFIG_EVENT_TRACING. 1429 1370 1430 CONFIG_LOCK_STAT defines "contended" 1371 CONFIG_LOCK_STAT defines "contended" and "acquired" lock events. 1431 (CONFIG_LOCKDEP defines "acquire" an 1372 (CONFIG_LOCKDEP defines "acquire" and "release" events.) 1432 1373 1433 config DEBUG_RT_MUTEXES 1374 config DEBUG_RT_MUTEXES 1434 bool "RT Mutex debugging, deadlock de 1375 bool "RT Mutex debugging, deadlock detection" 1435 depends on DEBUG_KERNEL && RT_MUTEXES 1376 depends on DEBUG_KERNEL && RT_MUTEXES 1436 help 1377 help 1437 This allows rt mutex semantics viola 1378 This allows rt mutex semantics violations and rt mutex related 1438 deadlocks (lockups) to be detected a 1379 deadlocks (lockups) to be detected and reported automatically. 1439 1380 1440 config DEBUG_SPINLOCK 1381 config DEBUG_SPINLOCK 1441 bool "Spinlock and rw-lock debugging: 1382 bool "Spinlock and rw-lock debugging: basic checks" 1442 depends on DEBUG_KERNEL 1383 depends on DEBUG_KERNEL 1443 select UNINLINE_SPIN_UNLOCK 1384 select UNINLINE_SPIN_UNLOCK 1444 help 1385 help 1445 Say Y here and build SMP to catch m 1386 Say Y here and build SMP to catch missing spinlock initialization 1446 and certain other kinds of spinlock 1387 and certain other kinds of spinlock errors commonly made. This is 1447 best used in conjunction with the N 1388 best used in conjunction with the NMI watchdog so that spinlock 1448 deadlocks are also debuggable. 1389 deadlocks are also debuggable. 1449 1390 1450 config DEBUG_MUTEXES 1391 config DEBUG_MUTEXES 1451 bool "Mutex debugging: basic checks" 1392 bool "Mutex debugging: basic checks" 1452 depends on DEBUG_KERNEL && !PREEMPT_R 1393 depends on DEBUG_KERNEL && !PREEMPT_RT 1453 help 1394 help 1454 This feature allows mutex semantics 1395 This feature allows mutex semantics violations to be detected and 1455 reported. 1396 reported. 1456 1397 1457 config DEBUG_WW_MUTEX_SLOWPATH 1398 config DEBUG_WW_MUTEX_SLOWPATH 1458 bool "Wait/wound mutex debugging: Slo 1399 bool "Wait/wound mutex debugging: Slowpath testing" 1459 depends on DEBUG_KERNEL && LOCK_DEBUG 1400 depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT 1460 select DEBUG_LOCK_ALLOC 1401 select DEBUG_LOCK_ALLOC 1461 select DEBUG_SPINLOCK 1402 select DEBUG_SPINLOCK 1462 select DEBUG_MUTEXES if !PREEMPT_RT 1403 select DEBUG_MUTEXES if !PREEMPT_RT 1463 select DEBUG_RT_MUTEXES if PREEMPT_RT 1404 select DEBUG_RT_MUTEXES if PREEMPT_RT 1464 help 1405 help 1465 This feature enables slowpath testin 1406 This feature enables slowpath testing for w/w mutex users by 1466 injecting additional -EDEADLK wound/ 1407 injecting additional -EDEADLK wound/backoff cases. Together with 1467 the full mutex checks enabled with ( 1408 the full mutex checks enabled with (CONFIG_PROVE_LOCKING) this 1468 will test all possible w/w mutex int 1409 will test all possible w/w mutex interface abuse with the 1469 exception of simply not acquiring al 1410 exception of simply not acquiring all the required locks. 1470 Note that this feature can introduce 1411 Note that this feature can introduce significant overhead, so 1471 it really should not be enabled in a 1412 it really should not be enabled in a production or distro kernel, 1472 even a debug kernel. If you are a d 1413 even a debug kernel. If you are a driver writer, enable it. If 1473 you are a distro, do not. 1414 you are a distro, do not. 1474 1415 1475 config DEBUG_RWSEMS 1416 config DEBUG_RWSEMS 1476 bool "RW Semaphore debugging: basic c 1417 bool "RW Semaphore debugging: basic checks" 1477 depends on DEBUG_KERNEL && !PREEMPT_R !! 1418 depends on DEBUG_KERNEL 1478 help 1419 help 1479 This debugging feature allows misma 1420 This debugging feature allows mismatched rw semaphore locks 1480 and unlocks to be detected and repo 1421 and unlocks to be detected and reported. 1481 1422 1482 config DEBUG_LOCK_ALLOC 1423 config DEBUG_LOCK_ALLOC 1483 bool "Lock debugging: detect incorrec 1424 bool "Lock debugging: detect incorrect freeing of live locks" 1484 depends on DEBUG_KERNEL && LOCK_DEBUG 1425 depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT 1485 select DEBUG_SPINLOCK 1426 select DEBUG_SPINLOCK 1486 select DEBUG_MUTEXES if !PREEMPT_RT 1427 select DEBUG_MUTEXES if !PREEMPT_RT 1487 select DEBUG_RT_MUTEXES if RT_MUTEXES 1428 select DEBUG_RT_MUTEXES if RT_MUTEXES 1488 select LOCKDEP 1429 select LOCKDEP 1489 help 1430 help 1490 This feature will check whether any 1431 This feature will check whether any held lock (spinlock, rwlock, 1491 mutex or rwsem) is incorrectly freed 1432 mutex or rwsem) is incorrectly freed by the kernel, via any of the 1492 memory-freeing routines (kfree(), km 1433 memory-freeing routines (kfree(), kmem_cache_free(), free_pages(), 1493 vfree(), etc.), whether a live lock 1434 vfree(), etc.), whether a live lock is incorrectly reinitialized via 1494 spin_lock_init()/mutex_init()/etc., 1435 spin_lock_init()/mutex_init()/etc., or whether there is any lock 1495 held during task exit. 1436 held during task exit. 1496 1437 1497 config LOCKDEP 1438 config LOCKDEP 1498 bool 1439 bool 1499 depends on DEBUG_KERNEL && LOCK_DEBUG 1440 depends on DEBUG_KERNEL && LOCK_DEBUGGING_SUPPORT 1500 select STACKTRACE 1441 select STACKTRACE 1501 select KALLSYMS 1442 select KALLSYMS 1502 select KALLSYMS_ALL 1443 select KALLSYMS_ALL 1503 1444 1504 config LOCKDEP_SMALL 1445 config LOCKDEP_SMALL 1505 bool 1446 bool 1506 1447 1507 config LOCKDEP_BITS 1448 config LOCKDEP_BITS 1508 int "Bitsize for MAX_LOCKDEP_ENTRIES" 1449 int "Bitsize for MAX_LOCKDEP_ENTRIES" 1509 depends on LOCKDEP && !LOCKDEP_SMALL 1450 depends on LOCKDEP && !LOCKDEP_SMALL 1510 range 10 30 1451 range 10 30 1511 default 15 1452 default 15 1512 help 1453 help 1513 Try increasing this value if you hi 1454 Try increasing this value if you hit "BUG: MAX_LOCKDEP_ENTRIES too low!" message. 1514 1455 1515 config LOCKDEP_CHAINS_BITS 1456 config LOCKDEP_CHAINS_BITS 1516 int "Bitsize for MAX_LOCKDEP_CHAINS" 1457 int "Bitsize for MAX_LOCKDEP_CHAINS" 1517 depends on LOCKDEP && !LOCKDEP_SMALL 1458 depends on LOCKDEP && !LOCKDEP_SMALL 1518 range 10 30 1459 range 10 30 1519 default 16 1460 default 16 1520 help 1461 help 1521 Try increasing this value if you hi 1462 Try increasing this value if you hit "BUG: MAX_LOCKDEP_CHAINS too low!" message. 1522 1463 1523 config LOCKDEP_STACK_TRACE_BITS 1464 config LOCKDEP_STACK_TRACE_BITS 1524 int "Bitsize for MAX_STACK_TRACE_ENTR 1465 int "Bitsize for MAX_STACK_TRACE_ENTRIES" 1525 depends on LOCKDEP && !LOCKDEP_SMALL 1466 depends on LOCKDEP && !LOCKDEP_SMALL 1526 range 10 30 1467 range 10 30 1527 default 19 1468 default 19 1528 help 1469 help 1529 Try increasing this value if you hi 1470 Try increasing this value if you hit "BUG: MAX_STACK_TRACE_ENTRIES too low!" message. 1530 1471 1531 config LOCKDEP_STACK_TRACE_HASH_BITS 1472 config LOCKDEP_STACK_TRACE_HASH_BITS 1532 int "Bitsize for STACK_TRACE_HASH_SIZ 1473 int "Bitsize for STACK_TRACE_HASH_SIZE" 1533 depends on LOCKDEP && !LOCKDEP_SMALL 1474 depends on LOCKDEP && !LOCKDEP_SMALL 1534 range 10 30 1475 range 10 30 1535 default 14 1476 default 14 1536 help 1477 help 1537 Try increasing this value if you ne 1478 Try increasing this value if you need large STACK_TRACE_HASH_SIZE. 1538 1479 1539 config LOCKDEP_CIRCULAR_QUEUE_BITS 1480 config LOCKDEP_CIRCULAR_QUEUE_BITS 1540 int "Bitsize for elements in circular 1481 int "Bitsize for elements in circular_queue struct" 1541 depends on LOCKDEP 1482 depends on LOCKDEP 1542 range 10 30 1483 range 10 30 1543 default 12 1484 default 12 1544 help 1485 help 1545 Try increasing this value if you hi 1486 Try increasing this value if you hit "lockdep bfs error:-1" warning due to __cq_enqueue() failure. 1546 1487 1547 config DEBUG_LOCKDEP 1488 config DEBUG_LOCKDEP 1548 bool "Lock dependency engine debuggin 1489 bool "Lock dependency engine debugging" 1549 depends on DEBUG_KERNEL && LOCKDEP 1490 depends on DEBUG_KERNEL && LOCKDEP 1550 select DEBUG_IRQFLAGS 1491 select DEBUG_IRQFLAGS 1551 help 1492 help 1552 If you say Y here, the lock depende 1493 If you say Y here, the lock dependency engine will do 1553 additional runtime checks to debug 1494 additional runtime checks to debug itself, at the price 1554 of more runtime overhead. 1495 of more runtime overhead. 1555 1496 1556 config DEBUG_ATOMIC_SLEEP 1497 config DEBUG_ATOMIC_SLEEP 1557 bool "Sleep inside atomic section che 1498 bool "Sleep inside atomic section checking" 1558 select PREEMPT_COUNT 1499 select PREEMPT_COUNT 1559 depends on DEBUG_KERNEL 1500 depends on DEBUG_KERNEL 1560 depends on !ARCH_NO_PREEMPT 1501 depends on !ARCH_NO_PREEMPT 1561 help 1502 help 1562 If you say Y here, various routines 1503 If you say Y here, various routines which may sleep will become very 1563 noisy if they are called inside ato 1504 noisy if they are called inside atomic sections: when a spinlock is 1564 held, inside an rcu read side criti 1505 held, inside an rcu read side critical section, inside preempt disabled 1565 sections, inside an interrupt, etc. 1506 sections, inside an interrupt, etc... 1566 1507 1567 config DEBUG_LOCKING_API_SELFTESTS 1508 config DEBUG_LOCKING_API_SELFTESTS 1568 bool "Locking API boot-time self-test 1509 bool "Locking API boot-time self-tests" 1569 depends on DEBUG_KERNEL 1510 depends on DEBUG_KERNEL 1570 help 1511 help 1571 Say Y here if you want the kernel t 1512 Say Y here if you want the kernel to run a short self-test during 1572 bootup. The self-test checks whethe 1513 bootup. The self-test checks whether common types of locking bugs 1573 are detected by debugging mechanism 1514 are detected by debugging mechanisms or not. (if you disable 1574 lock debugging then those bugs won' 1515 lock debugging then those bugs won't be detected of course.) 1575 The following locking APIs are cove 1516 The following locking APIs are covered: spinlocks, rwlocks, 1576 mutexes and rwsems. 1517 mutexes and rwsems. 1577 1518 1578 config LOCK_TORTURE_TEST 1519 config LOCK_TORTURE_TEST 1579 tristate "torture tests for locking" 1520 tristate "torture tests for locking" 1580 depends on DEBUG_KERNEL 1521 depends on DEBUG_KERNEL 1581 select TORTURE_TEST 1522 select TORTURE_TEST 1582 help 1523 help 1583 This option provides a kernel modul 1524 This option provides a kernel module that runs torture tests 1584 on kernel locking primitives. The 1525 on kernel locking primitives. The kernel module may be built 1585 after the fact on the running kerne 1526 after the fact on the running kernel to be tested, if desired. 1586 1527 1587 Say Y here if you want kernel locki 1528 Say Y here if you want kernel locking-primitive torture tests 1588 to be built into the kernel. 1529 to be built into the kernel. 1589 Say M if you want these torture tes 1530 Say M if you want these torture tests to build as a module. 1590 Say N if you are unsure. 1531 Say N if you are unsure. 1591 1532 1592 config WW_MUTEX_SELFTEST 1533 config WW_MUTEX_SELFTEST 1593 tristate "Wait/wound mutex selftests" 1534 tristate "Wait/wound mutex selftests" 1594 help 1535 help 1595 This option provides a kernel modul 1536 This option provides a kernel module that runs tests on the 1596 on the struct ww_mutex locking API. 1537 on the struct ww_mutex locking API. 1597 1538 1598 It is recommended to enable DEBUG_W 1539 It is recommended to enable DEBUG_WW_MUTEX_SLOWPATH in conjunction 1599 with this test harness. 1540 with this test harness. 1600 1541 1601 Say M if you want these self tests 1542 Say M if you want these self tests to build as a module. 1602 Say N if you are unsure. 1543 Say N if you are unsure. 1603 1544 1604 config SCF_TORTURE_TEST 1545 config SCF_TORTURE_TEST 1605 tristate "torture tests for smp_call_ 1546 tristate "torture tests for smp_call_function*()" 1606 depends on DEBUG_KERNEL 1547 depends on DEBUG_KERNEL 1607 select TORTURE_TEST 1548 select TORTURE_TEST 1608 help 1549 help 1609 This option provides a kernel modul 1550 This option provides a kernel module that runs torture tests 1610 on the smp_call_function() family o 1551 on the smp_call_function() family of primitives. The kernel 1611 module may be built after the fact 1552 module may be built after the fact on the running kernel to 1612 be tested, if desired. 1553 be tested, if desired. 1613 1554 1614 config CSD_LOCK_WAIT_DEBUG 1555 config CSD_LOCK_WAIT_DEBUG 1615 bool "Debugging for csd_lock_wait(), 1556 bool "Debugging for csd_lock_wait(), called from smp_call_function*()" 1616 depends on DEBUG_KERNEL 1557 depends on DEBUG_KERNEL 1617 depends on 64BIT 1558 depends on 64BIT 1618 default n 1559 default n 1619 help 1560 help 1620 This option enables debug prints wh 1561 This option enables debug prints when CPUs are slow to respond 1621 to the smp_call_function*() IPI wra 1562 to the smp_call_function*() IPI wrappers. These debug prints 1622 include the IPI handler function cu 1563 include the IPI handler function currently executing (if any) 1623 and relevant stack traces. 1564 and relevant stack traces. 1624 1565 1625 config CSD_LOCK_WAIT_DEBUG_DEFAULT 1566 config CSD_LOCK_WAIT_DEBUG_DEFAULT 1626 bool "Default csd_lock_wait() debuggi 1567 bool "Default csd_lock_wait() debugging on at boot time" 1627 depends on CSD_LOCK_WAIT_DEBUG 1568 depends on CSD_LOCK_WAIT_DEBUG 1628 depends on 64BIT 1569 depends on 64BIT 1629 default n 1570 default n 1630 help 1571 help 1631 This option causes the csdlock_debu 1572 This option causes the csdlock_debug= kernel boot parameter to 1632 default to 1 (basic debugging) inst 1573 default to 1 (basic debugging) instead of 0 (no debugging). 1633 1574 1634 endmenu # lock debugging 1575 endmenu # lock debugging 1635 1576 1636 config TRACE_IRQFLAGS 1577 config TRACE_IRQFLAGS 1637 depends on TRACE_IRQFLAGS_SUPPORT 1578 depends on TRACE_IRQFLAGS_SUPPORT 1638 bool 1579 bool 1639 help 1580 help 1640 Enables hooks to interrupt enabling 1581 Enables hooks to interrupt enabling and disabling for 1641 either tracing or lock debugging. 1582 either tracing or lock debugging. 1642 1583 1643 config TRACE_IRQFLAGS_NMI 1584 config TRACE_IRQFLAGS_NMI 1644 def_bool y 1585 def_bool y 1645 depends on TRACE_IRQFLAGS 1586 depends on TRACE_IRQFLAGS 1646 depends on TRACE_IRQFLAGS_NMI_SUPPORT 1587 depends on TRACE_IRQFLAGS_NMI_SUPPORT 1647 1588 1648 config NMI_CHECK_CPU 1589 config NMI_CHECK_CPU 1649 bool "Debugging for CPUs failing to r 1590 bool "Debugging for CPUs failing to respond to backtrace requests" 1650 depends on DEBUG_KERNEL 1591 depends on DEBUG_KERNEL 1651 depends on X86 1592 depends on X86 1652 default n 1593 default n 1653 help 1594 help 1654 Enables debug prints when a CPU fai 1595 Enables debug prints when a CPU fails to respond to a given 1655 backtrace NMI. These prints provid 1596 backtrace NMI. These prints provide some reasons why a CPU 1656 might legitimately be failing to re 1597 might legitimately be failing to respond, for example, if it 1657 is offline of if ignore_nmis is set 1598 is offline of if ignore_nmis is set. 1658 1599 1659 config DEBUG_IRQFLAGS 1600 config DEBUG_IRQFLAGS 1660 bool "Debug IRQ flag manipulation" 1601 bool "Debug IRQ flag manipulation" 1661 help 1602 help 1662 Enables checks for potentially unsa 1603 Enables checks for potentially unsafe enabling or disabling of 1663 interrupts, such as calling raw_loc 1604 interrupts, such as calling raw_local_irq_restore() when interrupts 1664 are enabled. 1605 are enabled. 1665 1606 1666 config STACKTRACE 1607 config STACKTRACE 1667 bool "Stack backtrace support" 1608 bool "Stack backtrace support" 1668 depends on STACKTRACE_SUPPORT 1609 depends on STACKTRACE_SUPPORT 1669 help 1610 help 1670 This option causes the kernel to cr 1611 This option causes the kernel to create a /proc/pid/stack for 1671 every process, showing its current 1612 every process, showing its current stack trace. 1672 It is also used by various kernel d 1613 It is also used by various kernel debugging features that require 1673 stack trace generation. 1614 stack trace generation. 1674 1615 1675 config WARN_ALL_UNSEEDED_RANDOM 1616 config WARN_ALL_UNSEEDED_RANDOM 1676 bool "Warn for all uses of unseeded r 1617 bool "Warn for all uses of unseeded randomness" 1677 default n 1618 default n 1678 help 1619 help 1679 Some parts of the kernel contain bu 1620 Some parts of the kernel contain bugs relating to their use of 1680 cryptographically secure random num 1621 cryptographically secure random numbers before it's actually possible 1681 to generate those numbers securely. 1622 to generate those numbers securely. This setting ensures that these 1682 flaws don't go unnoticed, by enabli 1623 flaws don't go unnoticed, by enabling a message, should this ever 1683 occur. This will allow people with 1624 occur. This will allow people with obscure setups to know when things 1684 are going wrong, so that they might 1625 are going wrong, so that they might contact developers about fixing 1685 it. 1626 it. 1686 1627 1687 Unfortunately, on some models of so 1628 Unfortunately, on some models of some architectures getting 1688 a fully seeded CRNG is extremely di 1629 a fully seeded CRNG is extremely difficult, and so this can 1689 result in dmesg getting spammed for 1630 result in dmesg getting spammed for a surprisingly long 1690 time. This is really bad from a se 1631 time. This is really bad from a security perspective, and 1691 so architecture maintainers really 1632 so architecture maintainers really need to do what they can 1692 to get the CRNG seeded sooner after 1633 to get the CRNG seeded sooner after the system is booted. 1693 However, since users cannot do anyt 1634 However, since users cannot do anything actionable to 1694 address this, by default this optio 1635 address this, by default this option is disabled. 1695 1636 1696 Say Y here if you want to receive w 1637 Say Y here if you want to receive warnings for all uses of 1697 unseeded randomness. This will be 1638 unseeded randomness. This will be of use primarily for 1698 those developers interested in impr 1639 those developers interested in improving the security of 1699 Linux kernels running on their arch 1640 Linux kernels running on their architecture (or 1700 subarchitecture). 1641 subarchitecture). 1701 1642 1702 config DEBUG_KOBJECT 1643 config DEBUG_KOBJECT 1703 bool "kobject debugging" 1644 bool "kobject debugging" 1704 depends on DEBUG_KERNEL 1645 depends on DEBUG_KERNEL 1705 help 1646 help 1706 If you say Y here, some extra kobje 1647 If you say Y here, some extra kobject debugging messages will be sent 1707 to the syslog. 1648 to the syslog. 1708 1649 1709 config DEBUG_KOBJECT_RELEASE 1650 config DEBUG_KOBJECT_RELEASE 1710 bool "kobject release debugging" 1651 bool "kobject release debugging" 1711 depends on DEBUG_OBJECTS_TIMERS 1652 depends on DEBUG_OBJECTS_TIMERS 1712 help 1653 help 1713 kobjects are reference counted obje 1654 kobjects are reference counted objects. This means that their 1714 last reference count put is not pre 1655 last reference count put is not predictable, and the kobject can 1715 live on past the point at which a d 1656 live on past the point at which a driver decides to drop its 1716 initial reference to the kobject ga 1657 initial reference to the kobject gained on allocation. An 1717 example of this would be a struct d 1658 example of this would be a struct device which has just been 1718 unregistered. 1659 unregistered. 1719 1660 1720 However, some buggy drivers assume 1661 However, some buggy drivers assume that after such an operation, 1721 the memory backing the kobject can 1662 the memory backing the kobject can be immediately freed. This 1722 goes completely against the princip 1663 goes completely against the principles of a refcounted object. 1723 1664 1724 If you say Y here, the kernel will 1665 If you say Y here, the kernel will delay the release of kobjects 1725 on the last reference count to impr 1666 on the last reference count to improve the visibility of this 1726 kind of kobject release bug. 1667 kind of kobject release bug. 1727 1668 1728 config HAVE_DEBUG_BUGVERBOSE 1669 config HAVE_DEBUG_BUGVERBOSE 1729 bool 1670 bool 1730 1671 1731 menu "Debug kernel data structures" 1672 menu "Debug kernel data structures" 1732 1673 1733 config DEBUG_LIST 1674 config DEBUG_LIST 1734 bool "Debug linked list manipulation" 1675 bool "Debug linked list manipulation" 1735 depends on DEBUG_KERNEL !! 1676 depends on DEBUG_KERNEL || BUG_ON_DATA_CORRUPTION 1736 select LIST_HARDENED << 1737 help 1677 help 1738 Enable this to turn on extended che !! 1678 Enable this to turn on extended checks in the linked-list 1739 routines. !! 1679 walking routines. 1740 << 1741 This option trades better quality e << 1742 is more suitable for kernel debuggi << 1743 you should only enable CONFIG_LIST_ << 1744 1680 1745 If unsure, say N. 1681 If unsure, say N. 1746 1682 1747 config DEBUG_PLIST 1683 config DEBUG_PLIST 1748 bool "Debug priority linked list mani 1684 bool "Debug priority linked list manipulation" 1749 depends on DEBUG_KERNEL 1685 depends on DEBUG_KERNEL 1750 help 1686 help 1751 Enable this to turn on extended che 1687 Enable this to turn on extended checks in the priority-ordered 1752 linked-list (plist) walking routine 1688 linked-list (plist) walking routines. This checks the entire 1753 list multiple times during each man 1689 list multiple times during each manipulation. 1754 1690 1755 If unsure, say N. 1691 If unsure, say N. 1756 1692 1757 config DEBUG_SG 1693 config DEBUG_SG 1758 bool "Debug SG table operations" 1694 bool "Debug SG table operations" 1759 depends on DEBUG_KERNEL 1695 depends on DEBUG_KERNEL 1760 help 1696 help 1761 Enable this to turn on checks on sc 1697 Enable this to turn on checks on scatter-gather tables. This can 1762 help find problems with drivers tha 1698 help find problems with drivers that do not properly initialize 1763 their sg tables. 1699 their sg tables. 1764 1700 1765 If unsure, say N. 1701 If unsure, say N. 1766 1702 1767 config DEBUG_NOTIFIERS 1703 config DEBUG_NOTIFIERS 1768 bool "Debug notifier call chains" 1704 bool "Debug notifier call chains" 1769 depends on DEBUG_KERNEL 1705 depends on DEBUG_KERNEL 1770 help 1706 help 1771 Enable this to turn on sanity check 1707 Enable this to turn on sanity checking for notifier call chains. 1772 This is most useful for kernel deve 1708 This is most useful for kernel developers to make sure that 1773 modules properly unregister themsel 1709 modules properly unregister themselves from notifier chains. 1774 This is a relatively cheap check bu 1710 This is a relatively cheap check but if you care about maximum 1775 performance, say N. 1711 performance, say N. 1776 1712 1777 config DEBUG_CLOSURES !! 1713 config BUG_ON_DATA_CORRUPTION 1778 bool "Debug closures (bcache async wi !! 1714 bool "Trigger a BUG when data corruption is detected" 1779 depends on CLOSURES !! 1715 select DEBUG_LIST 1780 select DEBUG_FS !! 1716 help 1781 help !! 1717 Select this option if the kernel should BUG when it encounters 1782 Keeps all active closures in a link !! 1718 data corruption in kernel memory structures when they get checked 1783 interface to list them, which makes !! 1719 for validity. 1784 operations that get stuck. !! 1720 >> 1721 If unsure, say N. 1785 1722 1786 config DEBUG_MAPLE_TREE 1723 config DEBUG_MAPLE_TREE 1787 bool "Debug maple trees" 1724 bool "Debug maple trees" 1788 depends on DEBUG_KERNEL 1725 depends on DEBUG_KERNEL 1789 help 1726 help 1790 Enable maple tree debugging informa 1727 Enable maple tree debugging information and extra validations. 1791 1728 1792 If unsure, say N. 1729 If unsure, say N. 1793 1730 1794 endmenu 1731 endmenu 1795 1732 >> 1733 config DEBUG_CREDENTIALS >> 1734 bool "Debug credential management" >> 1735 depends on DEBUG_KERNEL >> 1736 help >> 1737 Enable this to turn on some debug checking for credential >> 1738 management. The additional code keeps track of the number of >> 1739 pointers from task_structs to any given cred struct, and checks to >> 1740 see that this number never exceeds the usage count of the cred >> 1741 struct. >> 1742 >> 1743 Furthermore, if SELinux is enabled, this also checks that the >> 1744 security pointer in the cred struct is never seen to be invalid. >> 1745 >> 1746 If unsure, say N. >> 1747 1796 source "kernel/rcu/Kconfig.debug" 1748 source "kernel/rcu/Kconfig.debug" 1797 1749 1798 config DEBUG_WQ_FORCE_RR_CPU 1750 config DEBUG_WQ_FORCE_RR_CPU 1799 bool "Force round-robin CPU selection 1751 bool "Force round-robin CPU selection for unbound work items" 1800 depends on DEBUG_KERNEL 1752 depends on DEBUG_KERNEL 1801 default n 1753 default n 1802 help 1754 help 1803 Workqueue used to implicitly guaran 1755 Workqueue used to implicitly guarantee that work items queued 1804 without explicit CPU specified are 1756 without explicit CPU specified are put on the local CPU. This 1805 guarantee is no longer true and whi 1757 guarantee is no longer true and while local CPU is still 1806 preferred work items may be put on 1758 preferred work items may be put on foreign CPUs. Kernel 1807 parameter "workqueue.debug_force_rr 1759 parameter "workqueue.debug_force_rr_cpu" is added to force 1808 round-robin CPU selection to flush 1760 round-robin CPU selection to flush out usages which depend on the 1809 now broken guarantee. This config 1761 now broken guarantee. This config option enables the debug 1810 feature by default. When enabled, 1762 feature by default. When enabled, memory and cache locality will 1811 be impacted. 1763 be impacted. 1812 1764 1813 config CPU_HOTPLUG_STATE_CONTROL 1765 config CPU_HOTPLUG_STATE_CONTROL 1814 bool "Enable CPU hotplug state contro 1766 bool "Enable CPU hotplug state control" 1815 depends on DEBUG_KERNEL 1767 depends on DEBUG_KERNEL 1816 depends on HOTPLUG_CPU 1768 depends on HOTPLUG_CPU 1817 default n 1769 default n 1818 help 1770 help 1819 Allows to write steps between "offl 1771 Allows to write steps between "offline" and "online" to the CPUs 1820 sysfs target file so states can be 1772 sysfs target file so states can be stepped granular. This is a debug 1821 option for now as the hotplug machi 1773 option for now as the hotplug machinery cannot be stopped and 1822 restarted at arbitrary points yet. 1774 restarted at arbitrary points yet. 1823 1775 1824 Say N if your are unsure. 1776 Say N if your are unsure. 1825 1777 1826 config LATENCYTOP 1778 config LATENCYTOP 1827 bool "Latency measuring infrastructur 1779 bool "Latency measuring infrastructure" 1828 depends on DEBUG_KERNEL 1780 depends on DEBUG_KERNEL 1829 depends on STACKTRACE_SUPPORT 1781 depends on STACKTRACE_SUPPORT 1830 depends on PROC_FS 1782 depends on PROC_FS 1831 depends on FRAME_POINTER || MIPS || P 1783 depends on FRAME_POINTER || MIPS || PPC || S390 || MICROBLAZE || ARM || ARC || X86 1832 select KALLSYMS 1784 select KALLSYMS 1833 select KALLSYMS_ALL 1785 select KALLSYMS_ALL 1834 select STACKTRACE 1786 select STACKTRACE 1835 select SCHEDSTATS 1787 select SCHEDSTATS 1836 help 1788 help 1837 Enable this option if you want to u 1789 Enable this option if you want to use the LatencyTOP tool 1838 to find out which userspace is bloc 1790 to find out which userspace is blocking on what kernel operations. 1839 1791 1840 config DEBUG_CGROUP_REF 1792 config DEBUG_CGROUP_REF 1841 bool "Disable inlining of cgroup css 1793 bool "Disable inlining of cgroup css reference count functions" 1842 depends on DEBUG_KERNEL 1794 depends on DEBUG_KERNEL 1843 depends on CGROUPS 1795 depends on CGROUPS 1844 depends on KPROBES 1796 depends on KPROBES 1845 default n 1797 default n 1846 help 1798 help 1847 Force cgroup css reference count fu 1799 Force cgroup css reference count functions to not be inlined so 1848 that they can be kprobed for debugg 1800 that they can be kprobed for debugging. 1849 1801 1850 source "kernel/trace/Kconfig" 1802 source "kernel/trace/Kconfig" 1851 1803 1852 config PROVIDE_OHCI1394_DMA_INIT 1804 config PROVIDE_OHCI1394_DMA_INIT 1853 bool "Remote debugging over FireWire 1805 bool "Remote debugging over FireWire early on boot" 1854 depends on PCI && X86 1806 depends on PCI && X86 1855 help 1807 help 1856 If you want to debug problems which 1808 If you want to debug problems which hang or crash the kernel early 1857 on boot and the crashing machine ha 1809 on boot and the crashing machine has a FireWire port, you can use 1858 this feature to remotely access the 1810 this feature to remotely access the memory of the crashed machine 1859 over FireWire. This employs remote 1811 over FireWire. This employs remote DMA as part of the OHCI1394 1860 specification which is now the stan 1812 specification which is now the standard for FireWire controllers. 1861 1813 1862 With remote DMA, you can monitor th 1814 With remote DMA, you can monitor the printk buffer remotely using 1863 firescope and access all memory bel 1815 firescope and access all memory below 4GB using fireproxy from gdb. 1864 Even controlling a kernel debugger 1816 Even controlling a kernel debugger is possible using remote DMA. 1865 1817 1866 Usage: 1818 Usage: 1867 1819 1868 If ohci1394_dma=early is used as bo 1820 If ohci1394_dma=early is used as boot parameter, it will initialize 1869 all OHCI1394 controllers which are 1821 all OHCI1394 controllers which are found in the PCI config space. 1870 1822 1871 As all changes to the FireWire bus 1823 As all changes to the FireWire bus such as enabling and disabling 1872 devices cause a bus reset and there 1824 devices cause a bus reset and thereby disable remote DMA for all 1873 devices, be sure to have the cable 1825 devices, be sure to have the cable plugged and FireWire enabled on 1874 the debugging host before booting t 1826 the debugging host before booting the debug target for debugging. 1875 1827 1876 This code (~1k) is freed after boot 1828 This code (~1k) is freed after boot. By then, the firewire stack 1877 in charge of the OHCI-1394 controll 1829 in charge of the OHCI-1394 controllers should be used instead. 1878 1830 1879 See Documentation/core-api/debuggin 1831 See Documentation/core-api/debugging-via-ohci1394.rst for more information. 1880 1832 1881 source "samples/Kconfig" 1833 source "samples/Kconfig" 1882 1834 1883 config ARCH_HAS_DEVMEM_IS_ALLOWED 1835 config ARCH_HAS_DEVMEM_IS_ALLOWED 1884 bool 1836 bool 1885 1837 1886 config STRICT_DEVMEM 1838 config STRICT_DEVMEM 1887 bool "Filter access to /dev/mem" 1839 bool "Filter access to /dev/mem" 1888 depends on MMU && DEVMEM 1840 depends on MMU && DEVMEM 1889 depends on ARCH_HAS_DEVMEM_IS_ALLOWED 1841 depends on ARCH_HAS_DEVMEM_IS_ALLOWED || GENERIC_LIB_DEVMEM_IS_ALLOWED 1890 default y if PPC || X86 || ARM64 1842 default y if PPC || X86 || ARM64 1891 help 1843 help 1892 If this option is disabled, you all 1844 If this option is disabled, you allow userspace (root) access to all 1893 of memory, including kernel and use 1845 of memory, including kernel and userspace memory. Accidental 1894 access to this is obviously disastr 1846 access to this is obviously disastrous, but specific access can 1895 be used by people debugging the ker 1847 be used by people debugging the kernel. Note that with PAT support 1896 enabled, even in this case there ar 1848 enabled, even in this case there are restrictions on /dev/mem 1897 use due to the cache aliasing requi 1849 use due to the cache aliasing requirements. 1898 1850 1899 If this option is switched on, and 1851 If this option is switched on, and IO_STRICT_DEVMEM=n, the /dev/mem 1900 file only allows userspace access t 1852 file only allows userspace access to PCI space and the BIOS code and 1901 data regions. This is sufficient f 1853 data regions. This is sufficient for dosemu and X and all common 1902 users of /dev/mem. 1854 users of /dev/mem. 1903 1855 1904 If in doubt, say Y. 1856 If in doubt, say Y. 1905 1857 1906 config IO_STRICT_DEVMEM 1858 config IO_STRICT_DEVMEM 1907 bool "Filter I/O access to /dev/mem" 1859 bool "Filter I/O access to /dev/mem" 1908 depends on STRICT_DEVMEM 1860 depends on STRICT_DEVMEM 1909 help 1861 help 1910 If this option is disabled, you all 1862 If this option is disabled, you allow userspace (root) access to all 1911 io-memory regardless of whether a d 1863 io-memory regardless of whether a driver is actively using that 1912 range. Accidental access to this i 1864 range. Accidental access to this is obviously disastrous, but 1913 specific access can be used by peop 1865 specific access can be used by people debugging kernel drivers. 1914 1866 1915 If this option is switched on, the 1867 If this option is switched on, the /dev/mem file only allows 1916 userspace access to *idle* io-memor 1868 userspace access to *idle* io-memory ranges (see /proc/iomem) This 1917 may break traditional users of /dev 1869 may break traditional users of /dev/mem (dosemu, legacy X, etc...) 1918 if the driver using a given range c 1870 if the driver using a given range cannot be disabled. 1919 1871 1920 If in doubt, say Y. 1872 If in doubt, say Y. 1921 1873 1922 menu "$(SRCARCH) Debugging" 1874 menu "$(SRCARCH) Debugging" 1923 1875 1924 source "arch/$(SRCARCH)/Kconfig.debug" 1876 source "arch/$(SRCARCH)/Kconfig.debug" 1925 1877 1926 endmenu 1878 endmenu 1927 1879 1928 menu "Kernel Testing and Coverage" 1880 menu "Kernel Testing and Coverage" 1929 1881 1930 source "lib/kunit/Kconfig" 1882 source "lib/kunit/Kconfig" 1931 1883 1932 config NOTIFIER_ERROR_INJECTION 1884 config NOTIFIER_ERROR_INJECTION 1933 tristate "Notifier error injection" 1885 tristate "Notifier error injection" 1934 depends on DEBUG_KERNEL 1886 depends on DEBUG_KERNEL 1935 select DEBUG_FS 1887 select DEBUG_FS 1936 help 1888 help 1937 This option provides the ability to 1889 This option provides the ability to inject artificial errors to 1938 specified notifier chain callbacks. 1890 specified notifier chain callbacks. It is useful to test the error 1939 handling of notifier call chain fai 1891 handling of notifier call chain failures. 1940 1892 1941 Say N if unsure. 1893 Say N if unsure. 1942 1894 1943 config PM_NOTIFIER_ERROR_INJECT 1895 config PM_NOTIFIER_ERROR_INJECT 1944 tristate "PM notifier error injection 1896 tristate "PM notifier error injection module" 1945 depends on PM && NOTIFIER_ERROR_INJEC 1897 depends on PM && NOTIFIER_ERROR_INJECTION 1946 default m if PM_DEBUG 1898 default m if PM_DEBUG 1947 help 1899 help 1948 This option provides the ability to 1900 This option provides the ability to inject artificial errors to 1949 PM notifier chain callbacks. It is 1901 PM notifier chain callbacks. It is controlled through debugfs 1950 interface /sys/kernel/debug/notifie 1902 interface /sys/kernel/debug/notifier-error-inject/pm 1951 1903 1952 If the notifier call chain should b 1904 If the notifier call chain should be failed with some events 1953 notified, write the error code to " 1905 notified, write the error code to "actions/<notifier event>/error". 1954 1906 1955 Example: Inject PM suspend error (- 1907 Example: Inject PM suspend error (-12 = -ENOMEM) 1956 1908 1957 # cd /sys/kernel/debug/notifier-err 1909 # cd /sys/kernel/debug/notifier-error-inject/pm/ 1958 # echo -12 > actions/PM_SUSPEND_PRE 1910 # echo -12 > actions/PM_SUSPEND_PREPARE/error 1959 # echo mem > /sys/power/state 1911 # echo mem > /sys/power/state 1960 bash: echo: write error: Cannot all 1912 bash: echo: write error: Cannot allocate memory 1961 1913 1962 To compile this code as a module, c 1914 To compile this code as a module, choose M here: the module will 1963 be called pm-notifier-error-inject. 1915 be called pm-notifier-error-inject. 1964 1916 1965 If unsure, say N. 1917 If unsure, say N. 1966 1918 1967 config OF_RECONFIG_NOTIFIER_ERROR_INJECT 1919 config OF_RECONFIG_NOTIFIER_ERROR_INJECT 1968 tristate "OF reconfig notifier error 1920 tristate "OF reconfig notifier error injection module" 1969 depends on OF_DYNAMIC && NOTIFIER_ERR 1921 depends on OF_DYNAMIC && NOTIFIER_ERROR_INJECTION 1970 help 1922 help 1971 This option provides the ability to 1923 This option provides the ability to inject artificial errors to 1972 OF reconfig notifier chain callback 1924 OF reconfig notifier chain callbacks. It is controlled 1973 through debugfs interface under 1925 through debugfs interface under 1974 /sys/kernel/debug/notifier-error-in 1926 /sys/kernel/debug/notifier-error-inject/OF-reconfig/ 1975 1927 1976 If the notifier call chain should b 1928 If the notifier call chain should be failed with some events 1977 notified, write the error code to " 1929 notified, write the error code to "actions/<notifier event>/error". 1978 1930 1979 To compile this code as a module, c 1931 To compile this code as a module, choose M here: the module will 1980 be called of-reconfig-notifier-erro 1932 be called of-reconfig-notifier-error-inject. 1981 1933 1982 If unsure, say N. 1934 If unsure, say N. 1983 1935 1984 config NETDEV_NOTIFIER_ERROR_INJECT 1936 config NETDEV_NOTIFIER_ERROR_INJECT 1985 tristate "Netdev notifier error injec 1937 tristate "Netdev notifier error injection module" 1986 depends on NET && NOTIFIER_ERROR_INJE 1938 depends on NET && NOTIFIER_ERROR_INJECTION 1987 help 1939 help 1988 This option provides the ability to 1940 This option provides the ability to inject artificial errors to 1989 netdevice notifier chain callbacks. 1941 netdevice notifier chain callbacks. It is controlled through debugfs 1990 interface /sys/kernel/debug/notifie 1942 interface /sys/kernel/debug/notifier-error-inject/netdev 1991 1943 1992 If the notifier call chain should b 1944 If the notifier call chain should be failed with some events 1993 notified, write the error code to " 1945 notified, write the error code to "actions/<notifier event>/error". 1994 1946 1995 Example: Inject netdevice mtu chang 1947 Example: Inject netdevice mtu change error (-22 = -EINVAL) 1996 1948 1997 # cd /sys/kernel/debug/notifier-err 1949 # cd /sys/kernel/debug/notifier-error-inject/netdev 1998 # echo -22 > actions/NETDEV_CHANGEM 1950 # echo -22 > actions/NETDEV_CHANGEMTU/error 1999 # ip link set eth0 mtu 1024 1951 # ip link set eth0 mtu 1024 2000 RTNETLINK answers: Invalid argument 1952 RTNETLINK answers: Invalid argument 2001 1953 2002 To compile this code as a module, c 1954 To compile this code as a module, choose M here: the module will 2003 be called netdev-notifier-error-inj 1955 be called netdev-notifier-error-inject. 2004 1956 2005 If unsure, say N. 1957 If unsure, say N. 2006 1958 2007 config FUNCTION_ERROR_INJECTION 1959 config FUNCTION_ERROR_INJECTION 2008 bool "Fault-injections of functions" 1960 bool "Fault-injections of functions" 2009 depends on HAVE_FUNCTION_ERROR_INJECT 1961 depends on HAVE_FUNCTION_ERROR_INJECTION && KPROBES 2010 help 1962 help 2011 Add fault injections into various f 1963 Add fault injections into various functions that are annotated with 2012 ALLOW_ERROR_INJECTION() in the kern 1964 ALLOW_ERROR_INJECTION() in the kernel. BPF may also modify the return 2013 value of these functions. This is u 1965 value of these functions. This is useful to test error paths of code. 2014 1966 2015 If unsure, say N 1967 If unsure, say N 2016 1968 2017 config FAULT_INJECTION 1969 config FAULT_INJECTION 2018 bool "Fault-injection framework" 1970 bool "Fault-injection framework" 2019 depends on DEBUG_KERNEL 1971 depends on DEBUG_KERNEL 2020 help 1972 help 2021 Provide fault-injection framework. 1973 Provide fault-injection framework. 2022 For more details, see Documentation 1974 For more details, see Documentation/fault-injection/. 2023 1975 2024 config FAILSLAB 1976 config FAILSLAB 2025 bool "Fault-injection capability for 1977 bool "Fault-injection capability for kmalloc" 2026 depends on FAULT_INJECTION 1978 depends on FAULT_INJECTION >> 1979 depends on SLAB || SLUB 2027 help 1980 help 2028 Provide fault-injection capability 1981 Provide fault-injection capability for kmalloc. 2029 1982 2030 config FAIL_PAGE_ALLOC 1983 config FAIL_PAGE_ALLOC 2031 bool "Fault-injection capability for 1984 bool "Fault-injection capability for alloc_pages()" 2032 depends on FAULT_INJECTION 1985 depends on FAULT_INJECTION 2033 help 1986 help 2034 Provide fault-injection capability 1987 Provide fault-injection capability for alloc_pages(). 2035 1988 2036 config FAULT_INJECTION_USERCOPY 1989 config FAULT_INJECTION_USERCOPY 2037 bool "Fault injection capability for 1990 bool "Fault injection capability for usercopy functions" 2038 depends on FAULT_INJECTION 1991 depends on FAULT_INJECTION 2039 help 1992 help 2040 Provides fault-injection capability 1993 Provides fault-injection capability to inject failures 2041 in usercopy functions (copy_from_us 1994 in usercopy functions (copy_from_user(), get_user(), ...). 2042 1995 2043 config FAIL_MAKE_REQUEST 1996 config FAIL_MAKE_REQUEST 2044 bool "Fault-injection capability for 1997 bool "Fault-injection capability for disk IO" 2045 depends on FAULT_INJECTION && BLOCK 1998 depends on FAULT_INJECTION && BLOCK 2046 help 1999 help 2047 Provide fault-injection capability 2000 Provide fault-injection capability for disk IO. 2048 2001 2049 config FAIL_IO_TIMEOUT 2002 config FAIL_IO_TIMEOUT 2050 bool "Fault-injection capability for 2003 bool "Fault-injection capability for faking disk interrupts" 2051 depends on FAULT_INJECTION && BLOCK 2004 depends on FAULT_INJECTION && BLOCK 2052 help 2005 help 2053 Provide fault-injection capability 2006 Provide fault-injection capability on end IO handling. This 2054 will make the block layer "forget" 2007 will make the block layer "forget" an interrupt as configured, 2055 thus exercising the error handling. 2008 thus exercising the error handling. 2056 2009 2057 Only works with drivers that use th 2010 Only works with drivers that use the generic timeout handling, 2058 for others it won't do anything. 2011 for others it won't do anything. 2059 2012 2060 config FAIL_FUTEX 2013 config FAIL_FUTEX 2061 bool "Fault-injection capability for 2014 bool "Fault-injection capability for futexes" 2062 select DEBUG_FS 2015 select DEBUG_FS 2063 depends on FAULT_INJECTION && FUTEX 2016 depends on FAULT_INJECTION && FUTEX 2064 help 2017 help 2065 Provide fault-injection capability 2018 Provide fault-injection capability for futexes. 2066 2019 2067 config FAULT_INJECTION_DEBUG_FS 2020 config FAULT_INJECTION_DEBUG_FS 2068 bool "Debugfs entries for fault-injec 2021 bool "Debugfs entries for fault-injection capabilities" 2069 depends on FAULT_INJECTION && SYSFS & 2022 depends on FAULT_INJECTION && SYSFS && DEBUG_FS 2070 help 2023 help 2071 Enable configuration of fault-injec 2024 Enable configuration of fault-injection capabilities via debugfs. 2072 2025 2073 config FAIL_FUNCTION 2026 config FAIL_FUNCTION 2074 bool "Fault-injection capability for 2027 bool "Fault-injection capability for functions" 2075 depends on FAULT_INJECTION_DEBUG_FS & 2028 depends on FAULT_INJECTION_DEBUG_FS && FUNCTION_ERROR_INJECTION 2076 help 2029 help 2077 Provide function-based fault-inject 2030 Provide function-based fault-injection capability. 2078 This will allow you to override a s 2031 This will allow you to override a specific function with a return 2079 with given return value. As a resul 2032 with given return value. As a result, function caller will see 2080 an error value and have to handle i 2033 an error value and have to handle it. This is useful to test the 2081 error handling in various subsystem 2034 error handling in various subsystems. 2082 2035 2083 config FAIL_MMC_REQUEST 2036 config FAIL_MMC_REQUEST 2084 bool "Fault-injection capability for 2037 bool "Fault-injection capability for MMC IO" 2085 depends on FAULT_INJECTION_DEBUG_FS & 2038 depends on FAULT_INJECTION_DEBUG_FS && MMC 2086 help 2039 help 2087 Provide fault-injection capability 2040 Provide fault-injection capability for MMC IO. 2088 This will make the mmc core return 2041 This will make the mmc core return data errors. This is 2089 useful to test the error handling i 2042 useful to test the error handling in the mmc block device 2090 and to test how the mmc host driver 2043 and to test how the mmc host driver handles retries from 2091 the block device. 2044 the block device. 2092 2045 2093 config FAIL_SUNRPC 2046 config FAIL_SUNRPC 2094 bool "Fault-injection capability for 2047 bool "Fault-injection capability for SunRPC" 2095 depends on FAULT_INJECTION_DEBUG_FS & 2048 depends on FAULT_INJECTION_DEBUG_FS && SUNRPC_DEBUG 2096 help 2049 help 2097 Provide fault-injection capability 2050 Provide fault-injection capability for SunRPC and 2098 its consumers. 2051 its consumers. 2099 2052 2100 config FAULT_INJECTION_CONFIGFS 2053 config FAULT_INJECTION_CONFIGFS 2101 bool "Configfs interface for fault-in 2054 bool "Configfs interface for fault-injection capabilities" 2102 depends on FAULT_INJECTION 2055 depends on FAULT_INJECTION 2103 select CONFIGFS_FS 2056 select CONFIGFS_FS 2104 help 2057 help 2105 This option allows configfs-based d 2058 This option allows configfs-based drivers to dynamically configure 2106 fault-injection via configfs. Each 2059 fault-injection via configfs. Each parameter for driver-specific 2107 fault-injection can be made visible 2060 fault-injection can be made visible as a configfs attribute in a 2108 configfs group. 2061 configfs group. 2109 2062 2110 2063 2111 config FAULT_INJECTION_STACKTRACE_FILTER 2064 config FAULT_INJECTION_STACKTRACE_FILTER 2112 bool "stacktrace filter for fault-inj 2065 bool "stacktrace filter for fault-injection capabilities" 2113 depends on FAULT_INJECTION 2066 depends on FAULT_INJECTION 2114 depends on (FAULT_INJECTION_DEBUG_FS 2067 depends on (FAULT_INJECTION_DEBUG_FS || FAULT_INJECTION_CONFIGFS) && STACKTRACE_SUPPORT 2115 select STACKTRACE 2068 select STACKTRACE 2116 depends on FRAME_POINTER || MIPS || P 2069 depends on FRAME_POINTER || MIPS || PPC || S390 || MICROBLAZE || ARM || ARC || X86 2117 help 2070 help 2118 Provide stacktrace filter for fault 2071 Provide stacktrace filter for fault-injection capabilities 2119 2072 2120 config ARCH_HAS_KCOV 2073 config ARCH_HAS_KCOV 2121 bool 2074 bool 2122 help 2075 help 2123 An architecture should select this 2076 An architecture should select this when it can successfully 2124 build and run with CONFIG_KCOV. Thi 2077 build and run with CONFIG_KCOV. This typically requires 2125 disabling instrumentation for some 2078 disabling instrumentation for some early boot code. 2126 2079 2127 config CC_HAS_SANCOV_TRACE_PC 2080 config CC_HAS_SANCOV_TRACE_PC 2128 def_bool $(cc-option,-fsanitize-cover 2081 def_bool $(cc-option,-fsanitize-coverage=trace-pc) 2129 2082 2130 2083 2131 config KCOV 2084 config KCOV 2132 bool "Code coverage for fuzzing" 2085 bool "Code coverage for fuzzing" 2133 depends on ARCH_HAS_KCOV 2086 depends on ARCH_HAS_KCOV 2134 depends on CC_HAS_SANCOV_TRACE_PC || 2087 depends on CC_HAS_SANCOV_TRACE_PC || GCC_PLUGINS 2135 depends on !ARCH_WANTS_NO_INSTR || HA 2088 depends on !ARCH_WANTS_NO_INSTR || HAVE_NOINSTR_HACK || \ 2136 GCC_VERSION >= 120000 || C !! 2089 GCC_VERSION >= 120000 || CLANG_VERSION >= 130000 2137 select DEBUG_FS 2090 select DEBUG_FS 2138 select GCC_PLUGIN_SANCOV if !CC_HAS_S 2091 select GCC_PLUGIN_SANCOV if !CC_HAS_SANCOV_TRACE_PC 2139 select OBJTOOL if HAVE_NOINSTR_HACK 2092 select OBJTOOL if HAVE_NOINSTR_HACK 2140 help 2093 help 2141 KCOV exposes kernel code coverage i 2094 KCOV exposes kernel code coverage information in a form suitable 2142 for coverage-guided fuzzing (random 2095 for coverage-guided fuzzing (randomized testing). 2143 2096 >> 2097 If RANDOMIZE_BASE is enabled, PC values will not be stable across >> 2098 different machines and across reboots. If you need stable PC values, >> 2099 disable RANDOMIZE_BASE. >> 2100 2144 For more details, see Documentation 2101 For more details, see Documentation/dev-tools/kcov.rst. 2145 2102 2146 config KCOV_ENABLE_COMPARISONS 2103 config KCOV_ENABLE_COMPARISONS 2147 bool "Enable comparison operands coll 2104 bool "Enable comparison operands collection by KCOV" 2148 depends on KCOV 2105 depends on KCOV 2149 depends on $(cc-option,-fsanitize-cov 2106 depends on $(cc-option,-fsanitize-coverage=trace-cmp) 2150 help 2107 help 2151 KCOV also exposes operands of every 2108 KCOV also exposes operands of every comparison in the instrumented 2152 code along with operand sizes and P 2109 code along with operand sizes and PCs of the comparison instructions. 2153 These operands can be used by fuzzi 2110 These operands can be used by fuzzing engines to improve the quality 2154 of fuzzing coverage. 2111 of fuzzing coverage. 2155 2112 2156 config KCOV_INSTRUMENT_ALL 2113 config KCOV_INSTRUMENT_ALL 2157 bool "Instrument all code by default" 2114 bool "Instrument all code by default" 2158 depends on KCOV 2115 depends on KCOV 2159 default y 2116 default y 2160 help 2117 help 2161 If you are doing generic system cal 2118 If you are doing generic system call fuzzing (like e.g. syzkaller), 2162 then you will want to instrument th 2119 then you will want to instrument the whole kernel and you should 2163 say y here. If you are doing more t 2120 say y here. If you are doing more targeted fuzzing (like e.g. 2164 filesystem fuzzing with AFL) then y 2121 filesystem fuzzing with AFL) then you will want to enable coverage 2165 for more specific subsets of files, 2122 for more specific subsets of files, and should say n here. 2166 2123 2167 config KCOV_IRQ_AREA_SIZE 2124 config KCOV_IRQ_AREA_SIZE 2168 hex "Size of interrupt coverage colle 2125 hex "Size of interrupt coverage collection area in words" 2169 depends on KCOV 2126 depends on KCOV 2170 default 0x40000 2127 default 0x40000 2171 help 2128 help 2172 KCOV uses preallocated per-cpu area 2129 KCOV uses preallocated per-cpu areas to collect coverage from 2173 soft interrupts. This specifies the 2130 soft interrupts. This specifies the size of those areas in the 2174 number of unsigned long words. 2131 number of unsigned long words. 2175 2132 2176 menuconfig RUNTIME_TESTING_MENU 2133 menuconfig RUNTIME_TESTING_MENU 2177 bool "Runtime Testing" 2134 bool "Runtime Testing" 2178 default y !! 2135 def_bool y 2179 2136 2180 if RUNTIME_TESTING_MENU 2137 if RUNTIME_TESTING_MENU 2181 2138 2182 config TEST_DHRY 2139 config TEST_DHRY 2183 tristate "Dhrystone benchmark test" 2140 tristate "Dhrystone benchmark test" 2184 help 2141 help 2185 Enable this to include the Dhryston 2142 Enable this to include the Dhrystone 2.1 benchmark. This test 2186 calculates the number of Dhrystones 2143 calculates the number of Dhrystones per second, and the number of 2187 DMIPS (Dhrystone MIPS) obtained whe 2144 DMIPS (Dhrystone MIPS) obtained when the Dhrystone score is divided 2188 by 1757 (the number of Dhrystones p 2145 by 1757 (the number of Dhrystones per second obtained on the VAX 2189 11/780, nominally a 1 MIPS machine) 2146 11/780, nominally a 1 MIPS machine). 2190 2147 2191 To run the benchmark, it needs to b 2148 To run the benchmark, it needs to be enabled explicitly, either from 2192 the kernel command line (when built 2149 the kernel command line (when built-in), or from userspace (when 2193 built-in or modular). !! 2150 built-in or modular. 2194 2151 2195 Run once during kernel boot: 2152 Run once during kernel boot: 2196 2153 2197 test_dhry.run 2154 test_dhry.run 2198 2155 2199 Set number of iterations from kerne 2156 Set number of iterations from kernel command line: 2200 2157 2201 test_dhry.iterations=<n> 2158 test_dhry.iterations=<n> 2202 2159 2203 Set number of iterations from users 2160 Set number of iterations from userspace: 2204 2161 2205 echo <n> > /sys/module/test_dhr 2162 echo <n> > /sys/module/test_dhry/parameters/iterations 2206 2163 2207 Trigger manual run from userspace: 2164 Trigger manual run from userspace: 2208 2165 2209 echo y > /sys/module/test_dhry/ 2166 echo y > /sys/module/test_dhry/parameters/run 2210 2167 2211 If the number of iterations is <= 0 2168 If the number of iterations is <= 0, the test will devise a suitable 2212 number of iterations (test runs for 2169 number of iterations (test runs for at least 2s) automatically. 2213 This process takes ca. 4s. 2170 This process takes ca. 4s. 2214 2171 2215 If unsure, say N. 2172 If unsure, say N. 2216 2173 2217 config LKDTM 2174 config LKDTM 2218 tristate "Linux Kernel Dump Test Tool 2175 tristate "Linux Kernel Dump Test Tool Module" 2219 depends on DEBUG_FS 2176 depends on DEBUG_FS 2220 help 2177 help 2221 This module enables testing of the di 2178 This module enables testing of the different dumping mechanisms by 2222 inducing system failures at predefine 2179 inducing system failures at predefined crash points. 2223 If you don't need it: say N 2180 If you don't need it: say N 2224 Choose M here to compile this code as 2181 Choose M here to compile this code as a module. The module will be 2225 called lkdtm. 2182 called lkdtm. 2226 2183 2227 Documentation on how to use the modul 2184 Documentation on how to use the module can be found in 2228 Documentation/fault-injection/provoke 2185 Documentation/fault-injection/provoke-crashes.rst 2229 2186 2230 config CPUMASK_KUNIT_TEST 2187 config CPUMASK_KUNIT_TEST 2231 tristate "KUnit test for cpumask" if 2188 tristate "KUnit test for cpumask" if !KUNIT_ALL_TESTS 2232 depends on KUNIT 2189 depends on KUNIT 2233 default KUNIT_ALL_TESTS 2190 default KUNIT_ALL_TESTS 2234 help 2191 help 2235 Enable to turn on cpumask tests, ru 2192 Enable to turn on cpumask tests, running at boot or module load time. 2236 2193 2237 For more information on KUnit and u 2194 For more information on KUnit and unit tests in general, please refer 2238 to the KUnit documentation in Docum 2195 to the KUnit documentation in Documentation/dev-tools/kunit/. 2239 2196 2240 If unsure, say N. 2197 If unsure, say N. 2241 2198 2242 config TEST_LIST_SORT 2199 config TEST_LIST_SORT 2243 tristate "Linked list sorting test" i 2200 tristate "Linked list sorting test" if !KUNIT_ALL_TESTS 2244 depends on KUNIT 2201 depends on KUNIT 2245 default KUNIT_ALL_TESTS 2202 default KUNIT_ALL_TESTS 2246 help 2203 help 2247 Enable this to turn on 'list_sort() 2204 Enable this to turn on 'list_sort()' function test. This test is 2248 executed only once during system bo 2205 executed only once during system boot (so affects only boot time), 2249 or at module load time. 2206 or at module load time. 2250 2207 2251 If unsure, say N. 2208 If unsure, say N. 2252 2209 2253 config TEST_MIN_HEAP 2210 config TEST_MIN_HEAP 2254 tristate "Min heap test" 2211 tristate "Min heap test" 2255 depends on DEBUG_KERNEL || m 2212 depends on DEBUG_KERNEL || m 2256 help 2213 help 2257 Enable this to turn on min heap fun 2214 Enable this to turn on min heap function tests. This test is 2258 executed only once during system bo 2215 executed only once during system boot (so affects only boot time), 2259 or at module load time. 2216 or at module load time. 2260 2217 2261 If unsure, say N. 2218 If unsure, say N. 2262 2219 2263 config TEST_SORT 2220 config TEST_SORT 2264 tristate "Array-based sort test" if ! 2221 tristate "Array-based sort test" if !KUNIT_ALL_TESTS 2265 depends on KUNIT 2222 depends on KUNIT 2266 default KUNIT_ALL_TESTS 2223 default KUNIT_ALL_TESTS 2267 help 2224 help 2268 This option enables the self-test f 2225 This option enables the self-test function of 'sort()' at boot, 2269 or at module load time. 2226 or at module load time. 2270 2227 2271 If unsure, say N. 2228 If unsure, say N. 2272 2229 2273 config TEST_DIV64 2230 config TEST_DIV64 2274 tristate "64bit/32bit division and mo 2231 tristate "64bit/32bit division and modulo test" 2275 depends on DEBUG_KERNEL || m 2232 depends on DEBUG_KERNEL || m 2276 help 2233 help 2277 Enable this to turn on 'do_div()' f 2234 Enable this to turn on 'do_div()' function test. This test is 2278 executed only once during system bo 2235 executed only once during system boot (so affects only boot time), 2279 or at module load time. 2236 or at module load time. 2280 2237 2281 If unsure, say N. 2238 If unsure, say N. 2282 2239 2283 config TEST_IOV_ITER << 2284 tristate "Test iov_iter operation" if << 2285 depends on KUNIT << 2286 depends on MMU << 2287 default KUNIT_ALL_TESTS << 2288 help << 2289 Enable this to turn on testing of t << 2290 (iov_iter). This test is executed o << 2291 affects only boot time), or at modu << 2292 << 2293 If unsure, say N. << 2294 << 2295 config KPROBES_SANITY_TEST 2240 config KPROBES_SANITY_TEST 2296 tristate "Kprobes sanity tests" if !K 2241 tristate "Kprobes sanity tests" if !KUNIT_ALL_TESTS 2297 depends on DEBUG_KERNEL 2242 depends on DEBUG_KERNEL 2298 depends on KPROBES 2243 depends on KPROBES 2299 depends on KUNIT 2244 depends on KUNIT 2300 select STACKTRACE if ARCH_CORRECT_STA 2245 select STACKTRACE if ARCH_CORRECT_STACKTRACE_ON_KRETPROBE 2301 default KUNIT_ALL_TESTS 2246 default KUNIT_ALL_TESTS 2302 help 2247 help 2303 This option provides for testing ba 2248 This option provides for testing basic kprobes functionality on 2304 boot. Samples of kprobe and kretpro 2249 boot. Samples of kprobe and kretprobe are inserted and 2305 verified for functionality. 2250 verified for functionality. 2306 2251 2307 Say N if you are unsure. 2252 Say N if you are unsure. 2308 2253 2309 config FPROBE_SANITY_TEST 2254 config FPROBE_SANITY_TEST 2310 bool "Self test for fprobe" 2255 bool "Self test for fprobe" 2311 depends on DEBUG_KERNEL 2256 depends on DEBUG_KERNEL 2312 depends on FPROBE 2257 depends on FPROBE 2313 depends on KUNIT=y 2258 depends on KUNIT=y 2314 help 2259 help 2315 This option will enable testing the 2260 This option will enable testing the fprobe when the system boot. 2316 A series of tests are made to verif 2261 A series of tests are made to verify that the fprobe is functioning 2317 properly. 2262 properly. 2318 2263 2319 Say N if you are unsure. 2264 Say N if you are unsure. 2320 2265 2321 config BACKTRACE_SELF_TEST 2266 config BACKTRACE_SELF_TEST 2322 tristate "Self test for the backtrace 2267 tristate "Self test for the backtrace code" 2323 depends on DEBUG_KERNEL 2268 depends on DEBUG_KERNEL 2324 help 2269 help 2325 This option provides a kernel modul 2270 This option provides a kernel module that can be used to test 2326 the kernel stack backtrace code. Th 2271 the kernel stack backtrace code. This option is not useful 2327 for distributions or general kernel 2272 for distributions or general kernels, but only for kernel 2328 developers working on architecture 2273 developers working on architecture code. 2329 2274 2330 Note that if you want to also test 2275 Note that if you want to also test saved backtraces, you will 2331 have to enable STACKTRACE as well. 2276 have to enable STACKTRACE as well. 2332 2277 2333 Say N if you are unsure. 2278 Say N if you are unsure. 2334 2279 2335 config TEST_REF_TRACKER 2280 config TEST_REF_TRACKER 2336 tristate "Self test for reference tra 2281 tristate "Self test for reference tracker" 2337 depends on DEBUG_KERNEL && STACKTRACE 2282 depends on DEBUG_KERNEL && STACKTRACE_SUPPORT 2338 select REF_TRACKER 2283 select REF_TRACKER 2339 help 2284 help 2340 This option provides a kernel modul 2285 This option provides a kernel module performing tests 2341 using reference tracker infrastruct 2286 using reference tracker infrastructure. 2342 2287 2343 Say N if you are unsure. 2288 Say N if you are unsure. 2344 2289 2345 config RBTREE_TEST 2290 config RBTREE_TEST 2346 tristate "Red-Black tree test" 2291 tristate "Red-Black tree test" 2347 depends on DEBUG_KERNEL 2292 depends on DEBUG_KERNEL 2348 help 2293 help 2349 A benchmark measuring the performan 2294 A benchmark measuring the performance of the rbtree library. 2350 Also includes rbtree invariant chec 2295 Also includes rbtree invariant checks. 2351 2296 2352 config REED_SOLOMON_TEST 2297 config REED_SOLOMON_TEST 2353 tristate "Reed-Solomon library test" 2298 tristate "Reed-Solomon library test" 2354 depends on DEBUG_KERNEL || m 2299 depends on DEBUG_KERNEL || m 2355 select REED_SOLOMON 2300 select REED_SOLOMON 2356 select REED_SOLOMON_ENC16 2301 select REED_SOLOMON_ENC16 2357 select REED_SOLOMON_DEC16 2302 select REED_SOLOMON_DEC16 2358 help 2303 help 2359 This option enables the self-test f 2304 This option enables the self-test function of rslib at boot, 2360 or at module load time. 2305 or at module load time. 2361 2306 2362 If unsure, say N. 2307 If unsure, say N. 2363 2308 2364 config INTERVAL_TREE_TEST 2309 config INTERVAL_TREE_TEST 2365 tristate "Interval tree test" 2310 tristate "Interval tree test" 2366 depends on DEBUG_KERNEL 2311 depends on DEBUG_KERNEL 2367 select INTERVAL_TREE 2312 select INTERVAL_TREE 2368 help 2313 help 2369 A benchmark measuring the performan 2314 A benchmark measuring the performance of the interval tree library 2370 2315 2371 config PERCPU_TEST 2316 config PERCPU_TEST 2372 tristate "Per cpu operations test" 2317 tristate "Per cpu operations test" 2373 depends on m && DEBUG_KERNEL 2318 depends on m && DEBUG_KERNEL 2374 help 2319 help 2375 Enable this option to build test mo 2320 Enable this option to build test module which validates per-cpu 2376 operations. 2321 operations. 2377 2322 2378 If unsure, say N. 2323 If unsure, say N. 2379 2324 2380 config ATOMIC64_SELFTEST 2325 config ATOMIC64_SELFTEST 2381 tristate "Perform an atomic64_t self- 2326 tristate "Perform an atomic64_t self-test" 2382 help 2327 help 2383 Enable this option to test the atom 2328 Enable this option to test the atomic64_t functions at boot or 2384 at module load time. 2329 at module load time. 2385 2330 2386 If unsure, say N. 2331 If unsure, say N. 2387 2332 2388 config ASYNC_RAID6_TEST 2333 config ASYNC_RAID6_TEST 2389 tristate "Self test for hardware acce 2334 tristate "Self test for hardware accelerated raid6 recovery" 2390 depends on ASYNC_RAID6_RECOV 2335 depends on ASYNC_RAID6_RECOV 2391 select ASYNC_MEMCPY 2336 select ASYNC_MEMCPY 2392 help 2337 help 2393 This is a one-shot self test that p 2338 This is a one-shot self test that permutes through the 2394 recovery of all the possible two di 2339 recovery of all the possible two disk failure scenarios for a 2395 N-disk array. Recovery is performe 2340 N-disk array. Recovery is performed with the asynchronous 2396 raid6 recovery routines, and will o 2341 raid6 recovery routines, and will optionally use an offload 2397 engine if one is available. 2342 engine if one is available. 2398 2343 2399 If unsure, say N. 2344 If unsure, say N. 2400 2345 2401 config TEST_HEXDUMP 2346 config TEST_HEXDUMP 2402 tristate "Test functions located in t 2347 tristate "Test functions located in the hexdump module at runtime" 2403 2348 2404 config STRING_KUNIT_TEST !! 2349 config STRING_SELFTEST 2405 tristate "KUnit test string functions !! 2350 tristate "Test string functions at runtime" 2406 depends on KUNIT << 2407 default KUNIT_ALL_TESTS << 2408 2351 2409 config STRING_HELPERS_KUNIT_TEST !! 2352 config TEST_STRING_HELPERS 2410 tristate "KUnit test string helpers a !! 2353 tristate "Test functions located in the string_helpers module at runtime" 2411 depends on KUNIT << 2412 default KUNIT_ALL_TESTS << 2413 2354 2414 config TEST_KSTRTOX 2355 config TEST_KSTRTOX 2415 tristate "Test kstrto*() family of fu 2356 tristate "Test kstrto*() family of functions at runtime" 2416 2357 2417 config TEST_PRINTF 2358 config TEST_PRINTF 2418 tristate "Test printf() family of fun 2359 tristate "Test printf() family of functions at runtime" 2419 2360 2420 config TEST_SCANF 2361 config TEST_SCANF 2421 tristate "Test scanf() family of func 2362 tristate "Test scanf() family of functions at runtime" 2422 2363 2423 config TEST_BITMAP 2364 config TEST_BITMAP 2424 tristate "Test bitmap_*() family of f 2365 tristate "Test bitmap_*() family of functions at runtime" 2425 help 2366 help 2426 Enable this option to test the bitm 2367 Enable this option to test the bitmap functions at boot. 2427 2368 2428 If unsure, say N. 2369 If unsure, say N. 2429 2370 2430 config TEST_UUID 2371 config TEST_UUID 2431 tristate "Test functions located in t 2372 tristate "Test functions located in the uuid module at runtime" 2432 2373 2433 config TEST_XARRAY 2374 config TEST_XARRAY 2434 tristate "Test the XArray code at run 2375 tristate "Test the XArray code at runtime" 2435 2376 2436 config TEST_MAPLE_TREE 2377 config TEST_MAPLE_TREE 2437 tristate "Test the Maple Tree code at 2378 tristate "Test the Maple Tree code at runtime or module load" 2438 help 2379 help 2439 Enable this option to test the mapl 2380 Enable this option to test the maple tree code functions at boot, or 2440 when the module is loaded. Enable " 2381 when the module is loaded. Enable "Debug Maple Trees" will enable 2441 more verbose output on failures. 2382 more verbose output on failures. 2442 2383 2443 If unsure, say N. 2384 If unsure, say N. 2444 2385 2445 config TEST_RHASHTABLE 2386 config TEST_RHASHTABLE 2446 tristate "Perform selftest on resizab 2387 tristate "Perform selftest on resizable hash table" 2447 help 2388 help 2448 Enable this option to test the rhas 2389 Enable this option to test the rhashtable functions at boot. 2449 2390 2450 If unsure, say N. 2391 If unsure, say N. 2451 2392 2452 config TEST_IDA 2393 config TEST_IDA 2453 tristate "Perform selftest on IDA fun 2394 tristate "Perform selftest on IDA functions" 2454 2395 2455 config TEST_PARMAN 2396 config TEST_PARMAN 2456 tristate "Perform selftest on priorit 2397 tristate "Perform selftest on priority array manager" 2457 depends on PARMAN 2398 depends on PARMAN 2458 help 2399 help 2459 Enable this option to test priority 2400 Enable this option to test priority array manager on boot 2460 (or module load). 2401 (or module load). 2461 2402 2462 If unsure, say N. 2403 If unsure, say N. 2463 2404 2464 config TEST_IRQ_TIMINGS 2405 config TEST_IRQ_TIMINGS 2465 bool "IRQ timings selftest" 2406 bool "IRQ timings selftest" 2466 depends on IRQ_TIMINGS 2407 depends on IRQ_TIMINGS 2467 help 2408 help 2468 Enable this option to test the irq 2409 Enable this option to test the irq timings code on boot. 2469 2410 2470 If unsure, say N. 2411 If unsure, say N. 2471 2412 2472 config TEST_LKM 2413 config TEST_LKM 2473 tristate "Test module loading with 'h 2414 tristate "Test module loading with 'hello world' module" 2474 depends on m 2415 depends on m 2475 help 2416 help 2476 This builds the "test_module" modul 2417 This builds the "test_module" module that emits "Hello, world" 2477 on printk when loaded. It is design 2418 on printk when loaded. It is designed to be used for basic 2478 evaluation of the module loading su 2419 evaluation of the module loading subsystem (for example when 2479 validating module verification). It 2420 validating module verification). It lacks any extra dependencies, 2480 and will not normally be loaded by 2421 and will not normally be loaded by the system unless explicitly 2481 requested by name. 2422 requested by name. 2482 2423 2483 If unsure, say N. 2424 If unsure, say N. 2484 2425 2485 config TEST_BITOPS 2426 config TEST_BITOPS 2486 tristate "Test module for compilation 2427 tristate "Test module for compilation of bitops operations" >> 2428 depends on m 2487 help 2429 help 2488 This builds the "test_bitops" modul 2430 This builds the "test_bitops" module that is much like the 2489 TEST_LKM module except that it does 2431 TEST_LKM module except that it does a basic exercise of the 2490 set/clear_bit macros and get_count_ 2432 set/clear_bit macros and get_count_order/long to make sure there are 2491 no compiler warnings from C=1 spars 2433 no compiler warnings from C=1 sparse checker or -Wextra 2492 compilations. It has no dependencie 2434 compilations. It has no dependencies and doesn't run or load unless 2493 explicitly requested by name. for 2435 explicitly requested by name. for example: modprobe test_bitops. 2494 2436 2495 If unsure, say N. 2437 If unsure, say N. 2496 2438 2497 config TEST_VMALLOC 2439 config TEST_VMALLOC 2498 tristate "Test module for stress/perf 2440 tristate "Test module for stress/performance analysis of vmalloc allocator" 2499 default n 2441 default n 2500 depends on MMU 2442 depends on MMU 2501 depends on m 2443 depends on m 2502 help 2444 help 2503 This builds the "test_vmalloc" modu 2445 This builds the "test_vmalloc" module that should be used for 2504 stress and performance analysis. So 2446 stress and performance analysis. So, any new change for vmalloc 2505 subsystem can be evaluated from per 2447 subsystem can be evaluated from performance and stability point 2506 of view. 2448 of view. 2507 2449 2508 If unsure, say N. 2450 If unsure, say N. 2509 2451 >> 2452 config TEST_USER_COPY >> 2453 tristate "Test user/kernel boundary protections" >> 2454 depends on m >> 2455 help >> 2456 This builds the "test_user_copy" module that runs sanity checks >> 2457 on the copy_to/from_user infrastructure, making sure basic >> 2458 user/kernel boundary testing is working. If it fails to load, >> 2459 a regression has been detected in the user/kernel memory boundary >> 2460 protections. >> 2461 >> 2462 If unsure, say N. >> 2463 2510 config TEST_BPF 2464 config TEST_BPF 2511 tristate "Test BPF filter functionali 2465 tristate "Test BPF filter functionality" 2512 depends on m && NET 2466 depends on m && NET 2513 help 2467 help 2514 This builds the "test_bpf" module t 2468 This builds the "test_bpf" module that runs various test vectors 2515 against the BPF interpreter or BPF 2469 against the BPF interpreter or BPF JIT compiler depending on the 2516 current setting. This is in particu 2470 current setting. This is in particular useful for BPF JIT compiler 2517 development, but also to run regres 2471 development, but also to run regression tests against changes in 2518 the interpreter code. It also enabl 2472 the interpreter code. It also enables test stubs for eBPF maps and 2519 verifier used by user space verifie 2473 verifier used by user space verifier testsuite. 2520 2474 2521 If unsure, say N. 2475 If unsure, say N. 2522 2476 2523 config TEST_BLACKHOLE_DEV 2477 config TEST_BLACKHOLE_DEV 2524 tristate "Test blackhole netdev funct 2478 tristate "Test blackhole netdev functionality" 2525 depends on m && NET 2479 depends on m && NET 2526 help 2480 help 2527 This builds the "test_blackhole_dev 2481 This builds the "test_blackhole_dev" module that validates the 2528 data path through this blackhole ne 2482 data path through this blackhole netdev. 2529 2483 2530 If unsure, say N. 2484 If unsure, say N. 2531 2485 2532 config FIND_BIT_BENCHMARK 2486 config FIND_BIT_BENCHMARK 2533 tristate "Test find_bit functions" 2487 tristate "Test find_bit functions" 2534 help 2488 help 2535 This builds the "test_find_bit" mod 2489 This builds the "test_find_bit" module that measure find_*_bit() 2536 functions performance. 2490 functions performance. 2537 2491 2538 If unsure, say N. 2492 If unsure, say N. 2539 2493 2540 config TEST_FIRMWARE 2494 config TEST_FIRMWARE 2541 tristate "Test firmware loading via u 2495 tristate "Test firmware loading via userspace interface" 2542 depends on FW_LOADER 2496 depends on FW_LOADER 2543 help 2497 help 2544 This builds the "test_firmware" mod 2498 This builds the "test_firmware" module that creates a userspace 2545 interface for testing firmware load 2499 interface for testing firmware loading. This can be used to 2546 control the triggering of firmware 2500 control the triggering of firmware loading without needing an 2547 actual firmware-using device. The c 2501 actual firmware-using device. The contents can be rechecked by 2548 userspace. 2502 userspace. 2549 2503 2550 If unsure, say N. 2504 If unsure, say N. 2551 2505 2552 config TEST_SYSCTL 2506 config TEST_SYSCTL 2553 tristate "sysctl test driver" 2507 tristate "sysctl test driver" 2554 depends on PROC_SYSCTL 2508 depends on PROC_SYSCTL 2555 help 2509 help 2556 This builds the "test_sysctl" modul 2510 This builds the "test_sysctl" module. This driver enables to test the 2557 proc sysctl interfaces available to 2511 proc sysctl interfaces available to drivers safely without affecting 2558 production knobs which might alter 2512 production knobs which might alter system functionality. 2559 2513 2560 If unsure, say N. 2514 If unsure, say N. 2561 2515 2562 config BITFIELD_KUNIT 2516 config BITFIELD_KUNIT 2563 tristate "KUnit test bitfield functio 2517 tristate "KUnit test bitfield functions at runtime" if !KUNIT_ALL_TESTS 2564 depends on KUNIT 2518 depends on KUNIT 2565 default KUNIT_ALL_TESTS 2519 default KUNIT_ALL_TESTS 2566 help 2520 help 2567 Enable this option to test the bitf 2521 Enable this option to test the bitfield functions at boot. 2568 2522 2569 KUnit tests run during boot and out 2523 KUnit tests run during boot and output the results to the debug log 2570 in TAP format (http://testanything. 2524 in TAP format (http://testanything.org/). Only useful for kernel devs 2571 running the KUnit test harness, and 2525 running the KUnit test harness, and not intended for inclusion into a 2572 production build. 2526 production build. 2573 2527 2574 For more information on KUnit and u 2528 For more information on KUnit and unit tests in general please refer 2575 to the KUnit documentation in Docum 2529 to the KUnit documentation in Documentation/dev-tools/kunit/. 2576 2530 2577 If unsure, say N. 2531 If unsure, say N. 2578 2532 2579 config CHECKSUM_KUNIT 2533 config CHECKSUM_KUNIT 2580 tristate "KUnit test checksum functio 2534 tristate "KUnit test checksum functions at runtime" if !KUNIT_ALL_TESTS 2581 depends on KUNIT 2535 depends on KUNIT 2582 default KUNIT_ALL_TESTS 2536 default KUNIT_ALL_TESTS 2583 help 2537 help 2584 Enable this option to test the chec 2538 Enable this option to test the checksum functions at boot. 2585 2539 2586 KUnit tests run during boot and out 2540 KUnit tests run during boot and output the results to the debug log 2587 in TAP format (http://testanything. 2541 in TAP format (http://testanything.org/). Only useful for kernel devs 2588 running the KUnit test harness, and 2542 running the KUnit test harness, and not intended for inclusion into a 2589 production build. 2543 production build. 2590 2544 2591 For more information on KUnit and u 2545 For more information on KUnit and unit tests in general please refer 2592 to the KUnit documentation in Docum 2546 to the KUnit documentation in Documentation/dev-tools/kunit/. 2593 2547 2594 If unsure, say N. 2548 If unsure, say N. 2595 2549 2596 config HASH_KUNIT_TEST 2550 config HASH_KUNIT_TEST 2597 tristate "KUnit Test for integer hash 2551 tristate "KUnit Test for integer hash functions" if !KUNIT_ALL_TESTS 2598 depends on KUNIT 2552 depends on KUNIT 2599 default KUNIT_ALL_TESTS 2553 default KUNIT_ALL_TESTS 2600 help 2554 help 2601 Enable this option to test the kern 2555 Enable this option to test the kernel's string (<linux/stringhash.h>), and 2602 integer (<linux/hash.h>) hash funct 2556 integer (<linux/hash.h>) hash functions on boot. 2603 2557 2604 KUnit tests run during boot and out 2558 KUnit tests run during boot and output the results to the debug log 2605 in TAP format (https://testanything 2559 in TAP format (https://testanything.org/). Only useful for kernel devs 2606 running the KUnit test harness, and 2560 running the KUnit test harness, and not intended for inclusion into a 2607 production build. 2561 production build. 2608 2562 2609 For more information on KUnit and u 2563 For more information on KUnit and unit tests in general please refer 2610 to the KUnit documentation in Docum 2564 to the KUnit documentation in Documentation/dev-tools/kunit/. 2611 2565 2612 This is intended to help people wri 2566 This is intended to help people writing architecture-specific 2613 optimized versions. If unsure, say 2567 optimized versions. If unsure, say N. 2614 2568 2615 config RESOURCE_KUNIT_TEST 2569 config RESOURCE_KUNIT_TEST 2616 tristate "KUnit test for resource API 2570 tristate "KUnit test for resource API" if !KUNIT_ALL_TESTS 2617 depends on KUNIT 2571 depends on KUNIT 2618 default KUNIT_ALL_TESTS 2572 default KUNIT_ALL_TESTS 2619 help 2573 help 2620 This builds the resource API unit t 2574 This builds the resource API unit test. 2621 Tests the logic of API provided by 2575 Tests the logic of API provided by resource.c and ioport.h. 2622 For more information on KUnit and u 2576 For more information on KUnit and unit tests in general please refer 2623 to the KUnit documentation in Docum 2577 to the KUnit documentation in Documentation/dev-tools/kunit/. 2624 2578 2625 If unsure, say N. 2579 If unsure, say N. 2626 2580 2627 config SYSCTL_KUNIT_TEST 2581 config SYSCTL_KUNIT_TEST 2628 tristate "KUnit test for sysctl" if ! 2582 tristate "KUnit test for sysctl" if !KUNIT_ALL_TESTS 2629 depends on KUNIT 2583 depends on KUNIT 2630 default KUNIT_ALL_TESTS 2584 default KUNIT_ALL_TESTS 2631 help 2585 help 2632 This builds the proc sysctl unit te 2586 This builds the proc sysctl unit test, which runs on boot. 2633 Tests the API contract and implemen 2587 Tests the API contract and implementation correctness of sysctl. 2634 For more information on KUnit and u 2588 For more information on KUnit and unit tests in general please refer 2635 to the KUnit documentation in Docum 2589 to the KUnit documentation in Documentation/dev-tools/kunit/. 2636 2590 2637 If unsure, say N. 2591 If unsure, say N. 2638 2592 2639 config LIST_KUNIT_TEST 2593 config LIST_KUNIT_TEST 2640 tristate "KUnit Test for Kernel Linke 2594 tristate "KUnit Test for Kernel Linked-list structures" if !KUNIT_ALL_TESTS 2641 depends on KUNIT 2595 depends on KUNIT 2642 default KUNIT_ALL_TESTS 2596 default KUNIT_ALL_TESTS 2643 help 2597 help 2644 This builds the linked list KUnit t 2598 This builds the linked list KUnit test suite. 2645 It tests that the API and basic fun 2599 It tests that the API and basic functionality of the list_head type 2646 and associated macros. 2600 and associated macros. 2647 2601 2648 KUnit tests run during boot and out 2602 KUnit tests run during boot and output the results to the debug log 2649 in TAP format (https://testanything 2603 in TAP format (https://testanything.org/). Only useful for kernel devs 2650 running the KUnit test harness, and 2604 running the KUnit test harness, and not intended for inclusion into a 2651 production build. 2605 production build. 2652 2606 2653 For more information on KUnit and u 2607 For more information on KUnit and unit tests in general please refer 2654 to the KUnit documentation in Docum 2608 to the KUnit documentation in Documentation/dev-tools/kunit/. 2655 2609 2656 If unsure, say N. 2610 If unsure, say N. 2657 2611 2658 config HASHTABLE_KUNIT_TEST 2612 config HASHTABLE_KUNIT_TEST 2659 tristate "KUnit Test for Kernel Hasht 2613 tristate "KUnit Test for Kernel Hashtable structures" if !KUNIT_ALL_TESTS 2660 depends on KUNIT 2614 depends on KUNIT 2661 default KUNIT_ALL_TESTS 2615 default KUNIT_ALL_TESTS 2662 help 2616 help 2663 This builds the hashtable KUnit tes 2617 This builds the hashtable KUnit test suite. 2664 It tests the basic functionality of 2618 It tests the basic functionality of the API defined in 2665 include/linux/hashtable.h. For more 2619 include/linux/hashtable.h. For more information on KUnit and 2666 unit tests in general please refer 2620 unit tests in general please refer to the KUnit documentation 2667 in Documentation/dev-tools/kunit/. 2621 in Documentation/dev-tools/kunit/. 2668 2622 2669 If unsure, say N. 2623 If unsure, say N. 2670 2624 2671 config LINEAR_RANGES_TEST 2625 config LINEAR_RANGES_TEST 2672 tristate "KUnit test for linear_range 2626 tristate "KUnit test for linear_ranges" 2673 depends on KUNIT 2627 depends on KUNIT 2674 select LINEAR_RANGES 2628 select LINEAR_RANGES 2675 help 2629 help 2676 This builds the linear_ranges unit 2630 This builds the linear_ranges unit test, which runs on boot. 2677 Tests the linear_ranges logic corre 2631 Tests the linear_ranges logic correctness. 2678 For more information on KUnit and u 2632 For more information on KUnit and unit tests in general please refer 2679 to the KUnit documentation in Docum 2633 to the KUnit documentation in Documentation/dev-tools/kunit/. 2680 2634 2681 If unsure, say N. 2635 If unsure, say N. 2682 2636 2683 config CMDLINE_KUNIT_TEST 2637 config CMDLINE_KUNIT_TEST 2684 tristate "KUnit test for cmdline API" 2638 tristate "KUnit test for cmdline API" if !KUNIT_ALL_TESTS 2685 depends on KUNIT 2639 depends on KUNIT 2686 default KUNIT_ALL_TESTS 2640 default KUNIT_ALL_TESTS 2687 help 2641 help 2688 This builds the cmdline API unit te 2642 This builds the cmdline API unit test. 2689 Tests the logic of API provided by 2643 Tests the logic of API provided by cmdline.c. 2690 For more information on KUnit and u 2644 For more information on KUnit and unit tests in general please refer 2691 to the KUnit documentation in Docum 2645 to the KUnit documentation in Documentation/dev-tools/kunit/. 2692 2646 2693 If unsure, say N. 2647 If unsure, say N. 2694 2648 2695 config BITS_TEST 2649 config BITS_TEST 2696 tristate "KUnit test for bits.h" if ! 2650 tristate "KUnit test for bits.h" if !KUNIT_ALL_TESTS 2697 depends on KUNIT 2651 depends on KUNIT 2698 default KUNIT_ALL_TESTS 2652 default KUNIT_ALL_TESTS 2699 help 2653 help 2700 This builds the bits unit test. 2654 This builds the bits unit test. 2701 Tests the logic of macros defined i 2655 Tests the logic of macros defined in bits.h. 2702 For more information on KUnit and u 2656 For more information on KUnit and unit tests in general please refer 2703 to the KUnit documentation in Docum 2657 to the KUnit documentation in Documentation/dev-tools/kunit/. 2704 2658 2705 If unsure, say N. 2659 If unsure, say N. 2706 2660 2707 config SLUB_KUNIT_TEST 2661 config SLUB_KUNIT_TEST 2708 tristate "KUnit test for SLUB cache e 2662 tristate "KUnit test for SLUB cache error detection" if !KUNIT_ALL_TESTS 2709 depends on SLUB_DEBUG && KUNIT 2663 depends on SLUB_DEBUG && KUNIT 2710 default KUNIT_ALL_TESTS 2664 default KUNIT_ALL_TESTS 2711 help 2665 help 2712 This builds SLUB allocator unit tes 2666 This builds SLUB allocator unit test. 2713 Tests SLUB cache debugging function 2667 Tests SLUB cache debugging functionality. 2714 For more information on KUnit and u 2668 For more information on KUnit and unit tests in general please refer 2715 to the KUnit documentation in Docum 2669 to the KUnit documentation in Documentation/dev-tools/kunit/. 2716 2670 2717 If unsure, say N. 2671 If unsure, say N. 2718 2672 2719 config RATIONAL_KUNIT_TEST 2673 config RATIONAL_KUNIT_TEST 2720 tristate "KUnit test for rational.c" 2674 tristate "KUnit test for rational.c" if !KUNIT_ALL_TESTS 2721 depends on KUNIT && RATIONAL 2675 depends on KUNIT && RATIONAL 2722 default KUNIT_ALL_TESTS 2676 default KUNIT_ALL_TESTS 2723 help 2677 help 2724 This builds the rational math unit 2678 This builds the rational math unit test. 2725 For more information on KUnit and u 2679 For more information on KUnit and unit tests in general please refer 2726 to the KUnit documentation in Docum 2680 to the KUnit documentation in Documentation/dev-tools/kunit/. 2727 2681 2728 If unsure, say N. 2682 If unsure, say N. 2729 2683 2730 config MEMCPY_KUNIT_TEST 2684 config MEMCPY_KUNIT_TEST 2731 tristate "Test memcpy(), memmove(), a 2685 tristate "Test memcpy(), memmove(), and memset() functions at runtime" if !KUNIT_ALL_TESTS 2732 depends on KUNIT 2686 depends on KUNIT 2733 default KUNIT_ALL_TESTS 2687 default KUNIT_ALL_TESTS 2734 help 2688 help 2735 Builds unit tests for memcpy(), mem 2689 Builds unit tests for memcpy(), memmove(), and memset() functions. 2736 For more information on KUnit and u 2690 For more information on KUnit and unit tests in general please refer 2737 to the KUnit documentation in Docum 2691 to the KUnit documentation in Documentation/dev-tools/kunit/. 2738 2692 2739 If unsure, say N. 2693 If unsure, say N. 2740 2694 >> 2695 config MEMCPY_SLOW_KUNIT_TEST >> 2696 bool "Include exhaustive memcpy tests" >> 2697 depends on MEMCPY_KUNIT_TEST >> 2698 default y >> 2699 help >> 2700 Some memcpy tests are quite exhaustive in checking for overlaps >> 2701 and bit ranges. These can be very slow, so they are split out >> 2702 as a separate config, in case they need to be disabled. >> 2703 2741 config IS_SIGNED_TYPE_KUNIT_TEST 2704 config IS_SIGNED_TYPE_KUNIT_TEST 2742 tristate "Test is_signed_type() macro 2705 tristate "Test is_signed_type() macro" if !KUNIT_ALL_TESTS 2743 depends on KUNIT 2706 depends on KUNIT 2744 default KUNIT_ALL_TESTS 2707 default KUNIT_ALL_TESTS 2745 help 2708 help 2746 Builds unit tests for the is_signed 2709 Builds unit tests for the is_signed_type() macro. 2747 2710 2748 For more information on KUnit and u 2711 For more information on KUnit and unit tests in general please refer 2749 to the KUnit documentation in Docum 2712 to the KUnit documentation in Documentation/dev-tools/kunit/. 2750 2713 2751 If unsure, say N. 2714 If unsure, say N. 2752 2715 2753 config OVERFLOW_KUNIT_TEST 2716 config OVERFLOW_KUNIT_TEST 2754 tristate "Test check_*_overflow() fun 2717 tristate "Test check_*_overflow() functions at runtime" if !KUNIT_ALL_TESTS 2755 depends on KUNIT 2718 depends on KUNIT 2756 default KUNIT_ALL_TESTS 2719 default KUNIT_ALL_TESTS 2757 help 2720 help 2758 Builds unit tests for the check_*_o 2721 Builds unit tests for the check_*_overflow(), size_*(), allocation, and 2759 related functions. 2722 related functions. 2760 2723 2761 For more information on KUnit and u 2724 For more information on KUnit and unit tests in general please refer 2762 to the KUnit documentation in Docum 2725 to the KUnit documentation in Documentation/dev-tools/kunit/. 2763 2726 2764 If unsure, say N. 2727 If unsure, say N. 2765 2728 2766 config STACKINIT_KUNIT_TEST 2729 config STACKINIT_KUNIT_TEST 2767 tristate "Test level of stack variabl 2730 tristate "Test level of stack variable initialization" if !KUNIT_ALL_TESTS 2768 depends on KUNIT 2731 depends on KUNIT 2769 default KUNIT_ALL_TESTS 2732 default KUNIT_ALL_TESTS 2770 help 2733 help 2771 Test if the kernel is zero-initiali 2734 Test if the kernel is zero-initializing stack variables and 2772 padding. Coverage is controlled by 2735 padding. Coverage is controlled by compiler flags, 2773 CONFIG_INIT_STACK_ALL_PATTERN, CONF 2736 CONFIG_INIT_STACK_ALL_PATTERN, CONFIG_INIT_STACK_ALL_ZERO, 2774 CONFIG_GCC_PLUGIN_STRUCTLEAK, CONFI 2737 CONFIG_GCC_PLUGIN_STRUCTLEAK, CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF, 2775 or CONFIG_GCC_PLUGIN_STRUCTLEAK_BYR 2738 or CONFIG_GCC_PLUGIN_STRUCTLEAK_BYREF_ALL. 2776 2739 2777 config FORTIFY_KUNIT_TEST 2740 config FORTIFY_KUNIT_TEST 2778 tristate "Test fortified str*() and m 2741 tristate "Test fortified str*() and mem*() function internals at runtime" if !KUNIT_ALL_TESTS 2779 depends on KUNIT !! 2742 depends on KUNIT && FORTIFY_SOURCE 2780 default KUNIT_ALL_TESTS 2743 default KUNIT_ALL_TESTS 2781 help 2744 help 2782 Builds unit tests for checking inte 2745 Builds unit tests for checking internals of FORTIFY_SOURCE as used 2783 by the str*() and mem*() family of 2746 by the str*() and mem*() family of functions. For testing runtime 2784 traps of FORTIFY_SOURCE, see LKDTM' 2747 traps of FORTIFY_SOURCE, see LKDTM's "FORTIFY_*" tests. 2785 2748 2786 config HW_BREAKPOINT_KUNIT_TEST 2749 config HW_BREAKPOINT_KUNIT_TEST 2787 bool "Test hw_breakpoint constraints 2750 bool "Test hw_breakpoint constraints accounting" if !KUNIT_ALL_TESTS 2788 depends on HAVE_HW_BREAKPOINT 2751 depends on HAVE_HW_BREAKPOINT 2789 depends on KUNIT=y 2752 depends on KUNIT=y 2790 default KUNIT_ALL_TESTS 2753 default KUNIT_ALL_TESTS 2791 help 2754 help 2792 Tests for hw_breakpoint constraints 2755 Tests for hw_breakpoint constraints accounting. 2793 2756 2794 If unsure, say N. 2757 If unsure, say N. 2795 2758 >> 2759 config STRCAT_KUNIT_TEST >> 2760 tristate "Test strcat() family of functions at runtime" if !KUNIT_ALL_TESTS >> 2761 depends on KUNIT >> 2762 default KUNIT_ALL_TESTS >> 2763 >> 2764 config STRSCPY_KUNIT_TEST >> 2765 tristate "Test strscpy*() family of functions at runtime" if !KUNIT_ALL_TESTS >> 2766 depends on KUNIT >> 2767 default KUNIT_ALL_TESTS >> 2768 2796 config SIPHASH_KUNIT_TEST 2769 config SIPHASH_KUNIT_TEST 2797 tristate "Perform selftest on siphash 2770 tristate "Perform selftest on siphash functions" if !KUNIT_ALL_TESTS 2798 depends on KUNIT 2771 depends on KUNIT 2799 default KUNIT_ALL_TESTS 2772 default KUNIT_ALL_TESTS 2800 help 2773 help 2801 Enable this option to test the kern 2774 Enable this option to test the kernel's siphash (<linux/siphash.h>) hash 2802 functions on boot (or module load). 2775 functions on boot (or module load). 2803 2776 2804 This is intended to help people wri 2777 This is intended to help people writing architecture-specific 2805 optimized versions. If unsure, say 2778 optimized versions. If unsure, say N. 2806 2779 2807 config USERCOPY_KUNIT_TEST << 2808 tristate "KUnit Test for user/kernel << 2809 depends on KUNIT << 2810 default KUNIT_ALL_TESTS << 2811 help << 2812 This builds the "usercopy_kunit" mo << 2813 on the copy_to/from_user infrastruc << 2814 user/kernel boundary testing is wor << 2815 << 2816 config TEST_UDELAY 2780 config TEST_UDELAY 2817 tristate "udelay test driver" 2781 tristate "udelay test driver" 2818 help 2782 help 2819 This builds the "udelay_test" modul 2783 This builds the "udelay_test" module that helps to make sure 2820 that udelay() is working properly. 2784 that udelay() is working properly. 2821 2785 2822 If unsure, say N. 2786 If unsure, say N. 2823 2787 2824 config TEST_STATIC_KEYS 2788 config TEST_STATIC_KEYS 2825 tristate "Test static keys" 2789 tristate "Test static keys" 2826 depends on m 2790 depends on m 2827 help 2791 help 2828 Test the static key interfaces. 2792 Test the static key interfaces. 2829 2793 2830 If unsure, say N. 2794 If unsure, say N. 2831 2795 2832 config TEST_DYNAMIC_DEBUG 2796 config TEST_DYNAMIC_DEBUG 2833 tristate "Test DYNAMIC_DEBUG" 2797 tristate "Test DYNAMIC_DEBUG" 2834 depends on DYNAMIC_DEBUG 2798 depends on DYNAMIC_DEBUG 2835 help 2799 help 2836 This module registers a tracer call 2800 This module registers a tracer callback to count enabled 2837 pr_debugs in a 'do_debugging' funct 2801 pr_debugs in a 'do_debugging' function, then alters their 2838 enablements, calls the function, an 2802 enablements, calls the function, and compares counts. 2839 2803 2840 If unsure, say N. 2804 If unsure, say N. 2841 2805 2842 config TEST_KMOD 2806 config TEST_KMOD 2843 tristate "kmod stress tester" 2807 tristate "kmod stress tester" 2844 depends on m 2808 depends on m 2845 depends on NETDEVICES && NET_CORE && 2809 depends on NETDEVICES && NET_CORE && INET # for TUN 2846 depends on BLOCK 2810 depends on BLOCK 2847 depends on PAGE_SIZE_LESS_THAN_256KB 2811 depends on PAGE_SIZE_LESS_THAN_256KB # for BTRFS 2848 select TEST_LKM 2812 select TEST_LKM 2849 select XFS_FS 2813 select XFS_FS 2850 select TUN 2814 select TUN 2851 select BTRFS_FS 2815 select BTRFS_FS 2852 help 2816 help 2853 Test the kernel's module loading me 2817 Test the kernel's module loading mechanism: kmod. kmod implements 2854 support to load modules using the L 2818 support to load modules using the Linux kernel's usermode helper. 2855 This test provides a series of test 2819 This test provides a series of tests against kmod. 2856 2820 2857 Although technically you can either 2821 Although technically you can either build test_kmod as a module or 2858 into the kernel we disallow buildin 2822 into the kernel we disallow building it into the kernel since 2859 it stress tests request_module() an 2823 it stress tests request_module() and this will very likely cause 2860 some issues by taking over precious 2824 some issues by taking over precious threads available from other 2861 module load requests, ultimately th 2825 module load requests, ultimately this could be fatal. 2862 2826 2863 To run tests run: 2827 To run tests run: 2864 2828 2865 tools/testing/selftests/kmod/kmod.s 2829 tools/testing/selftests/kmod/kmod.sh --help 2866 2830 2867 If unsure, say N. 2831 If unsure, say N. 2868 2832 2869 config TEST_DEBUG_VIRTUAL 2833 config TEST_DEBUG_VIRTUAL 2870 tristate "Test CONFIG_DEBUG_VIRTUAL f 2834 tristate "Test CONFIG_DEBUG_VIRTUAL feature" 2871 depends on DEBUG_VIRTUAL 2835 depends on DEBUG_VIRTUAL 2872 help 2836 help 2873 Test the kernel's ability to detect 2837 Test the kernel's ability to detect incorrect calls to 2874 virt_to_phys() done against the non 2838 virt_to_phys() done against the non-linear part of the 2875 kernel's virtual address map. 2839 kernel's virtual address map. 2876 2840 2877 If unsure, say N. 2841 If unsure, say N. 2878 2842 2879 config TEST_MEMCAT_P 2843 config TEST_MEMCAT_P 2880 tristate "Test memcat_p() helper func 2844 tristate "Test memcat_p() helper function" 2881 help 2845 help 2882 Test the memcat_p() helper for corr 2846 Test the memcat_p() helper for correctly merging two 2883 pointer arrays together. 2847 pointer arrays together. 2884 2848 2885 If unsure, say N. 2849 If unsure, say N. 2886 2850 >> 2851 config TEST_LIVEPATCH >> 2852 tristate "Test livepatching" >> 2853 default n >> 2854 depends on DYNAMIC_DEBUG >> 2855 depends on LIVEPATCH >> 2856 depends on m >> 2857 help >> 2858 Test kernel livepatching features for correctness. The tests will >> 2859 load test modules that will be livepatched in various scenarios. >> 2860 >> 2861 To run all the livepatching tests: >> 2862 >> 2863 make -C tools/testing/selftests TARGETS=livepatch run_tests >> 2864 >> 2865 Alternatively, individual tests may be invoked: >> 2866 >> 2867 tools/testing/selftests/livepatch/test-callbacks.sh >> 2868 tools/testing/selftests/livepatch/test-livepatch.sh >> 2869 tools/testing/selftests/livepatch/test-shadow-vars.sh >> 2870 >> 2871 If unsure, say N. >> 2872 2887 config TEST_OBJAGG 2873 config TEST_OBJAGG 2888 tristate "Perform selftest on object 2874 tristate "Perform selftest on object aggreration manager" 2889 default n 2875 default n 2890 depends on OBJAGG 2876 depends on OBJAGG 2891 help 2877 help 2892 Enable this option to test object a 2878 Enable this option to test object aggregation manager on boot 2893 (or module load). 2879 (or module load). 2894 2880 2895 config TEST_MEMINIT 2881 config TEST_MEMINIT 2896 tristate "Test heap/page initializati 2882 tristate "Test heap/page initialization" 2897 help 2883 help 2898 Test if the kernel is zero-initiali 2884 Test if the kernel is zero-initializing heap and page allocations. 2899 This can be useful to test init_on_ 2885 This can be useful to test init_on_alloc and init_on_free features. 2900 2886 2901 If unsure, say N. 2887 If unsure, say N. 2902 2888 2903 config TEST_HMM 2889 config TEST_HMM 2904 tristate "Test HMM (Heterogeneous Mem 2890 tristate "Test HMM (Heterogeneous Memory Management)" 2905 depends on TRANSPARENT_HUGEPAGE 2891 depends on TRANSPARENT_HUGEPAGE 2906 depends on DEVICE_PRIVATE 2892 depends on DEVICE_PRIVATE 2907 select HMM_MIRROR 2893 select HMM_MIRROR 2908 select MMU_NOTIFIER 2894 select MMU_NOTIFIER 2909 help 2895 help 2910 This is a pseudo device driver sole 2896 This is a pseudo device driver solely for testing HMM. 2911 Say M here if you want to build the 2897 Say M here if you want to build the HMM test module. 2912 Doing so will allow you to run tool 2898 Doing so will allow you to run tools/testing/selftest/vm/hmm-tests. 2913 2899 2914 If unsure, say N. 2900 If unsure, say N. 2915 2901 2916 config TEST_FREE_PAGES 2902 config TEST_FREE_PAGES 2917 tristate "Test freeing pages" 2903 tristate "Test freeing pages" 2918 help 2904 help 2919 Test that a memory leak does not oc 2905 Test that a memory leak does not occur due to a race between 2920 freeing a block of pages and a spec 2906 freeing a block of pages and a speculative page reference. 2921 Loading this module is safe if your 2907 Loading this module is safe if your kernel has the bug fixed. 2922 If the bug is not fixed, it will le 2908 If the bug is not fixed, it will leak gigabytes of memory and 2923 probably OOM your system. 2909 probably OOM your system. 2924 2910 2925 config TEST_FPU 2911 config TEST_FPU 2926 tristate "Test floating point operati 2912 tristate "Test floating point operations in kernel space" 2927 depends on ARCH_HAS_KERNEL_FPU_SUPPOR !! 2913 depends on X86 && !KCOV_INSTRUMENT_ALL 2928 help 2914 help 2929 Enable this option to add /sys/kern 2915 Enable this option to add /sys/kernel/debug/selftest_helpers/test_fpu 2930 which will trigger a sequence of fl 2916 which will trigger a sequence of floating point operations. This is used 2931 for self-testing floating point con 2917 for self-testing floating point control register setting in 2932 kernel_fpu_begin(). 2918 kernel_fpu_begin(). 2933 2919 2934 If unsure, say N. 2920 If unsure, say N. 2935 2921 2936 config TEST_CLOCKSOURCE_WATCHDOG 2922 config TEST_CLOCKSOURCE_WATCHDOG 2937 tristate "Test clocksource watchdog i 2923 tristate "Test clocksource watchdog in kernel space" 2938 depends on CLOCKSOURCE_WATCHDOG 2924 depends on CLOCKSOURCE_WATCHDOG 2939 help 2925 help 2940 Enable this option to create a kern 2926 Enable this option to create a kernel module that will trigger 2941 a test of the clocksource watchdog. 2927 a test of the clocksource watchdog. This module may be loaded 2942 via modprobe or insmod in which cas 2928 via modprobe or insmod in which case it will run upon being 2943 loaded, or it may be built in, in w 2929 loaded, or it may be built in, in which case it will run 2944 shortly after boot. 2930 shortly after boot. 2945 2931 2946 If unsure, say N. 2932 If unsure, say N. 2947 2933 2948 config TEST_OBJPOOL << 2949 tristate "Test module for correctness << 2950 default n << 2951 depends on m && DEBUG_KERNEL << 2952 help << 2953 This builds the "test_objpool" modu << 2954 correctness verification and concur << 2955 allocation and reclamation. << 2956 << 2957 If unsure, say N. << 2958 << 2959 endif # RUNTIME_TESTING_MENU 2934 endif # RUNTIME_TESTING_MENU 2960 2935 2961 config ARCH_USE_MEMTEST 2936 config ARCH_USE_MEMTEST 2962 bool 2937 bool 2963 help 2938 help 2964 An architecture should select this 2939 An architecture should select this when it uses early_memtest() 2965 during boot process. 2940 during boot process. 2966 2941 2967 config MEMTEST 2942 config MEMTEST 2968 bool "Memtest" 2943 bool "Memtest" 2969 depends on ARCH_USE_MEMTEST 2944 depends on ARCH_USE_MEMTEST 2970 help 2945 help 2971 This option adds a kernel parameter 2946 This option adds a kernel parameter 'memtest', which allows memtest 2972 to be set and executed. 2947 to be set and executed. 2973 memtest=0, mean disabled; -- 2948 memtest=0, mean disabled; -- default 2974 memtest=1, mean do 1 test pat 2949 memtest=1, mean do 1 test pattern; 2975 ... 2950 ... 2976 memtest=17, mean do 17 test p 2951 memtest=17, mean do 17 test patterns. 2977 If you are unsure how to answer thi 2952 If you are unsure how to answer this question, answer N. 2978 2953 2979 2954 2980 2955 2981 config HYPERV_TESTING 2956 config HYPERV_TESTING 2982 bool "Microsoft Hyper-V driver testin 2957 bool "Microsoft Hyper-V driver testing" 2983 default n 2958 default n 2984 depends on HYPERV && DEBUG_FS 2959 depends on HYPERV && DEBUG_FS 2985 help 2960 help 2986 Select this option to enable Hyper- 2961 Select this option to enable Hyper-V vmbus testing. 2987 2962 2988 endmenu # "Kernel Testing and Coverage" 2963 endmenu # "Kernel Testing and Coverage" 2989 2964 2990 menu "Rust hacking" 2965 menu "Rust hacking" 2991 2966 2992 config RUST_DEBUG_ASSERTIONS 2967 config RUST_DEBUG_ASSERTIONS 2993 bool "Debug assertions" 2968 bool "Debug assertions" 2994 depends on RUST 2969 depends on RUST 2995 help 2970 help 2996 Enables rustc's `-Cdebug-assertions 2971 Enables rustc's `-Cdebug-assertions` codegen option. 2997 2972 2998 This flag lets you turn `cfg(debug_ 2973 This flag lets you turn `cfg(debug_assertions)` conditional 2999 compilation on or off. This can be 2974 compilation on or off. This can be used to enable extra debugging 3000 code in development but not in prod 2975 code in development but not in production. For example, it controls 3001 the behavior of the standard librar 2976 the behavior of the standard library's `debug_assert!` macro. 3002 2977 3003 Note that this will apply to all Ru 2978 Note that this will apply to all Rust code, including `core`. 3004 2979 3005 If unsure, say N. 2980 If unsure, say N. 3006 2981 3007 config RUST_OVERFLOW_CHECKS 2982 config RUST_OVERFLOW_CHECKS 3008 bool "Overflow checks" 2983 bool "Overflow checks" 3009 default y 2984 default y 3010 depends on RUST 2985 depends on RUST 3011 help 2986 help 3012 Enables rustc's `-Coverflow-checks` 2987 Enables rustc's `-Coverflow-checks` codegen option. 3013 2988 3014 This flag allows you to control the 2989 This flag allows you to control the behavior of runtime integer 3015 overflow. When overflow-checks are 2990 overflow. When overflow-checks are enabled, a Rust panic will occur 3016 on overflow. 2991 on overflow. 3017 2992 3018 Note that this will apply to all Ru 2993 Note that this will apply to all Rust code, including `core`. 3019 2994 3020 If unsure, say Y. 2995 If unsure, say Y. 3021 2996 3022 config RUST_BUILD_ASSERT_ALLOW 2997 config RUST_BUILD_ASSERT_ALLOW 3023 bool "Allow unoptimized build-time as 2998 bool "Allow unoptimized build-time assertions" 3024 depends on RUST 2999 depends on RUST 3025 help 3000 help 3026 Controls how are `build_error!` and 3001 Controls how are `build_error!` and `build_assert!` handled during build. 3027 3002 3028 If calls to them exist in the binar 3003 If calls to them exist in the binary, it may indicate a violated invariant 3029 or that the optimizer failed to ver 3004 or that the optimizer failed to verify the invariant during compilation. 3030 3005 3031 This should not happen, thus by def 3006 This should not happen, thus by default the build is aborted. However, 3032 as an escape hatch, you can choose 3007 as an escape hatch, you can choose Y here to ignore them during build 3033 and let the check be carried at run 3008 and let the check be carried at runtime (with `panic!` being called if 3034 the check fails). 3009 the check fails). 3035 << 3036 If unsure, say N. << 3037 << 3038 config RUST_KERNEL_DOCTESTS << 3039 bool "Doctests for the `kernel` crate << 3040 depends on RUST && KUNIT=y << 3041 default KUNIT_ALL_TESTS << 3042 help << 3043 This builds the documentation tests << 3044 as KUnit tests. << 3045 << 3046 For more information on KUnit and u << 3047 please refer to the KUnit documenta << 3048 3010 3049 If unsure, say N. 3011 If unsure, say N. 3050 3012 3051 endmenu # "Rust" 3013 endmenu # "Rust" 3052 3014 3053 endmenu # Kernel hacking 3015 endmenu # Kernel hacking
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