1 # SPDX-License-Identifier: GPL-2.0-only
2 config CC_VERSION_TEXT
3 string
4 default "$(CC_VERSION_TEXT)"
5 help
6 This is used in unclear ways:
7
8 - Re-run Kconfig when the compiler i
9 The 'default' property references
10 CC_VERSION_TEXT so it is recorded
11 When the compiler is updated, Kcon
12
13 - Ensure full rebuild when the compi
14 include/linux/compiler-version.h c
15 line so fixdep adds include/config
16 auto-generated dependency. When th
17 will touch it and then every file
18
19 config CC_IS_GCC
20 def_bool $(success,test "$(cc-name)" =
21
22 config GCC_VERSION
23 int
24 default $(cc-version) if CC_IS_GCC
25 default 0
26
27 config CC_IS_CLANG
28 def_bool $(success,test "$(cc-name)" =
29
30 config CLANG_VERSION
31 int
32 default $(cc-version) if CC_IS_CLANG
33 default 0
34
35 config AS_IS_GNU
36 def_bool $(success,test "$(as-name)" =
37
38 config AS_IS_LLVM
39 def_bool $(success,test "$(as-name)" =
40
41 config AS_VERSION
42 int
43 # Use clang version if this is the int
44 default CLANG_VERSION if AS_IS_LLVM
45 default $(as-version)
46
47 config LD_IS_BFD
48 def_bool $(success,test "$(ld-name)" =
49
50 config LD_VERSION
51 int
52 default $(ld-version) if LD_IS_BFD
53 default 0
54
55 config LD_IS_LLD
56 def_bool $(success,test "$(ld-name)" =
57
58 config LLD_VERSION
59 int
60 default $(ld-version) if LD_IS_LLD
61 default 0
62
63 config RUSTC_VERSION
64 int
65 default $(rustc-version)
66 help
67 It does not depend on `RUST` since t
68 in a `depends on`.
69
70 config RUST_IS_AVAILABLE
71 def_bool $(success,$(srctree)/scripts/
72 help
73 This shows whether a suitable Rust t
74
75 Please see Documentation/rust/quick-
76 to satisfy the build requirements of
77
78 In particular, the Makefile target '
79 why the Rust toolchain is not being
80
81 config RUSTC_LLVM_VERSION
82 int
83 default $(rustc-llvm-version)
84
85 config CC_CAN_LINK
86 bool
87 default $(success,$(srctree)/scripts/c
88 default $(success,$(srctree)/scripts/c
89
90 config CC_CAN_LINK_STATIC
91 bool
92 default $(success,$(srctree)/scripts/c
93 default $(success,$(srctree)/scripts/c
94
95 # Fixed in GCC 14, 13.3, 12.4 and 11.5
96 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id
97 config GCC_ASM_GOTO_OUTPUT_BROKEN
98 bool
99 depends on CC_IS_GCC
100 default y if GCC_VERSION < 110500
101 default y if GCC_VERSION >= 120000 &&
102 default y if GCC_VERSION >= 130000 &&
103
104 config CC_HAS_ASM_GOTO_OUTPUT
105 def_bool y
106 depends on !GCC_ASM_GOTO_OUTPUT_BROKEN
107 depends on $(success,echo 'int foo(int
108
109 config CC_HAS_ASM_GOTO_TIED_OUTPUT
110 depends on CC_HAS_ASM_GOTO_OUTPUT
111 # Detect buggy gcc and clang, fixed in
112 def_bool $(success,echo 'int foo(int *
113
114 config TOOLS_SUPPORT_RELR
115 def_bool $(success,env "CC=$(CC)" "LD=
116
117 config CC_HAS_ASM_INLINE
118 def_bool $(success,echo 'void foo(void
119
120 config CC_HAS_NO_PROFILE_FN_ATTR
121 def_bool $(success,echo '__attribute__
122
123 config PAHOLE_VERSION
124 int
125 default $(shell,$(srctree)/scripts/pah
126
127 config CONSTRUCTORS
128 bool
129
130 config IRQ_WORK
131 def_bool y if SMP
132
133 config BUILDTIME_TABLE_SORT
134 bool
135
136 config THREAD_INFO_IN_TASK
137 bool
138 help
139 Select this to move thread_info off
140 make this work, an arch will need to
141 except flags and fix any runtime bug
142
143 One subtle change that will be neede
144 and put_task_stack() in save_thread_
145
146 menu "General setup"
147
148 config BROKEN
149 bool
150
151 config BROKEN_ON_SMP
152 bool
153 depends on BROKEN || !SMP
154 default y
155
156 config INIT_ENV_ARG_LIMIT
157 int
158 default 32 if !UML
159 default 128 if UML
160 help
161 Maximum of each of the number of arg
162 variables passed to init from the ke
163
164 config COMPILE_TEST
165 bool "Compile also drivers which will
166 depends on HAS_IOMEM
167 help
168 Some drivers can be compiled on a di
169 intended to be run on. Despite they
170 when they load they cannot be used d
171 developers still, opposing to distri
172 drivers to compile-test them.
173
174 If you are a developer and want to b
175 here. If you are a user/distributor,
176 drivers to be distributed.
177
178 config WERROR
179 bool "Compile the kernel with warnings
180 default COMPILE_TEST
181 help
182 A kernel build should not cause any
183 enables the '-Werror' (for C) and '-
184 to enforce that rule by default. Cer
185 such as the linker may be upgraded t
186 well.
187
188 However, if you have a new (or very
189 and unusual warnings, or you have so
190 you may need to disable this config
191 successfully build the kernel.
192
193 If in doubt, say Y.
194
195 config UAPI_HEADER_TEST
196 bool "Compile test UAPI headers"
197 depends on HEADERS_INSTALL && CC_CAN_L
198 help
199 Compile test headers exported to use
200 self-contained, i.e. compilable as s
201
202 If you are a developer or tester and
203 headers are self-contained, say Y he
204
205 config LOCALVERSION
206 string "Local version - append to kern
207 help
208 Append an extra string to the end of
209 This will show up when you type unam
210 The string you set here will be appe
211 any files with a filename matching l
212 object and source tree, in that orde
213 be a maximum of 64 characters.
214
215 config LOCALVERSION_AUTO
216 bool "Automatically append version inf
217 default y
218 depends on !COMPILE_TEST
219 help
220 This will try to automatically deter
221 release tree by looking for git tags
222 top of tree revision.
223
224 A string of the format -gxxxxxxxx wi
225 if a git-based tree is found. The s
226 appended after any matching localver
227 set in CONFIG_LOCALVERSION.
228
229 (The actual string used here is the
230 by running the command:
231
232 $ git rev-parse --verify HEAD
233
234 which is done within the script "scr
235
236 config BUILD_SALT
237 string "Build ID Salt"
238 default ""
239 help
240 The build ID is used to link binarie
241 this option will use the value in th
242 This is mostly useful for distributi
243 build is unique between builds. It's
244
245 config HAVE_KERNEL_GZIP
246 bool
247
248 config HAVE_KERNEL_BZIP2
249 bool
250
251 config HAVE_KERNEL_LZMA
252 bool
253
254 config HAVE_KERNEL_XZ
255 bool
256
257 config HAVE_KERNEL_LZO
258 bool
259
260 config HAVE_KERNEL_LZ4
261 bool
262
263 config HAVE_KERNEL_ZSTD
264 bool
265
266 config HAVE_KERNEL_UNCOMPRESSED
267 bool
268
269 choice
270 prompt "Kernel compression mode"
271 default KERNEL_GZIP
272 depends on HAVE_KERNEL_GZIP || HAVE_KE
273 help
274 The linux kernel is a kind of self-e
275 Several compression algorithms are a
276 in efficiency, compression and decom
277 Compression speed is only relevant w
278 Decompression speed is relevant at e
279
280 If you have any problems with bzip2
281 kernels, mail me (Alain Knaff) <alain
282 version of this functionality (bzip2
283 supplied by Christian Ludwig)
284
285 High compression options are mostly
286 are low on disk space (embedded syst
287 size matters less.
288
289 If in doubt, select 'gzip'
290
291 config KERNEL_GZIP
292 bool "Gzip"
293 depends on HAVE_KERNEL_GZIP
294 help
295 The old and tried gzip compression.
296 between compression ratio and decomp
297
298 config KERNEL_BZIP2
299 bool "Bzip2"
300 depends on HAVE_KERNEL_BZIP2
301 help
302 Its compression ratio and speed is i
303 Decompression speed is slowest among
304 size is about 10% smaller with bzip2
305 Bzip2 uses a large amount of memory.
306 will need at least 8MB RAM or more f
307
308 config KERNEL_LZMA
309 bool "LZMA"
310 depends on HAVE_KERNEL_LZMA
311 help
312 This compression algorithm's ratio i
313 is between gzip and bzip2. Compress
314 The kernel size is about 33% smaller
315
316 config KERNEL_XZ
317 bool "XZ"
318 depends on HAVE_KERNEL_XZ
319 help
320 XZ uses the LZMA2 algorithm and inst
321 BCJ filters which can improve compre
322 code. The size of the kernel is abou
323 comparison to gzip. On architectures
324 filter (i386, x86_64, ARM, ARM64, RI
325 and SPARC), XZ will create a few per
326 plain LZMA.
327
328 The speed is about the same as with
329 speed of XZ is better than that of b
330 and LZO. Compression is slow.
331
332 config KERNEL_LZO
333 bool "LZO"
334 depends on HAVE_KERNEL_LZO
335 help
336 Its compression ratio is the poorest
337 size is about 10% bigger than gzip;
338 (both compression and decompression)
339
340 config KERNEL_LZ4
341 bool "LZ4"
342 depends on HAVE_KERNEL_LZ4
343 help
344 LZ4 is an LZ77-type compressor with
345 A preliminary version of LZ4 de/comp
346 <https://code.google.com/p/lz4/>.
347
348 Its compression ratio is worse than
349 is about 8% bigger than LZO. But the
350 faster than LZO.
351
352 config KERNEL_ZSTD
353 bool "ZSTD"
354 depends on HAVE_KERNEL_ZSTD
355 help
356 ZSTD is a compression algorithm targ
357 with fast decompression speed. It wi
358 decompress around the same speed as
359 will need at least 192 KB RAM or mor
360 line tool is required for compressio
361
362 config KERNEL_UNCOMPRESSED
363 bool "None"
364 depends on HAVE_KERNEL_UNCOMPRESSED
365 help
366 Produce uncompressed kernel image. T
367 you want. It is useful for debugging
368 environments, where decompressing an
369 slow. This option allows early boot
370 and jump right at uncompressed kerne
371
372 endchoice
373
374 config DEFAULT_INIT
375 string "Default init path"
376 default ""
377 help
378 This option determines the default i
379 option is passed on the kernel comma
380 not present, we will still then move
381 locations (e.g. /sbin/init, etc). If
382 the fallback list when init= is not
383
384 config DEFAULT_HOSTNAME
385 string "Default hostname"
386 default "(none)"
387 help
388 This option determines the default s
389 calls sethostname(2). The kernel tra
390 but you may wish to use a different
391 system more usable with less configu
392
393 config SYSVIPC
394 bool "System V IPC"
395 help
396 Inter Process Communication is a sui
397 system calls which let processes (ru
398 exchange information. It is generall
399 and some programs won't run unless y
400 you want to run the DOS emulator dos
401 DOSEMU-HOWTO, available from <http:/
402 you'll need to say Y here.
403
404 You can find documentation about IPC
405 section 6.4 of the Linux Programmer'
406 <http://www.tldp.org/guides.html>.
407
408 config SYSVIPC_SYSCTL
409 bool
410 depends on SYSVIPC
411 depends on SYSCTL
412 default y
413
414 config SYSVIPC_COMPAT
415 def_bool y
416 depends on COMPAT && SYSVIPC
417
418 config POSIX_MQUEUE
419 bool "POSIX Message Queues"
420 depends on NET
421 help
422 POSIX variant of message queues is a
423 queues every message has a priority
424 of receiving it by a process. If you
425 programs written e.g. for Solaris wi
426 queues (functions mq_*) say Y here.
427
428 POSIX message queues are visible as
429 and can be mounted somewhere if you
430 operations on message queues.
431
432 If unsure, say Y.
433
434 config POSIX_MQUEUE_SYSCTL
435 bool
436 depends on POSIX_MQUEUE
437 depends on SYSCTL
438 default y
439
440 config WATCH_QUEUE
441 bool "General notification queue"
442 default n
443 help
444
445 This is a general notification queue
446 userspace by splicing them into pipe
447 with watches for key/keyring change
448 notifications.
449
450 See Documentation/core-api/watch_que
451
452 config CROSS_MEMORY_ATTACH
453 bool "Enable process_vm_readv/writev s
454 depends on MMU
455 default y
456 help
457 Enabling this option adds the system
458 process_vm_writev which allow a proc
459 to directly read from or write to an
460 See the man page for more details.
461
462 config USELIB
463 bool "uselib syscall (for libc5 and ea
464 default ALPHA || M68K || SPARC
465 help
466 This option enables the uselib sysca
467 dynamic linker from libc5 and earlie
468 system call. If you intend to run p
469 earlier, you may need to enable this
470 running glibc can safely disable thi
471
472 config AUDIT
473 bool "Auditing support"
474 depends on NET
475 help
476 Enable auditing infrastructure that
477 kernel subsystem, such as SELinux (w
478 logging of avc messages output). Sy
479 on architectures which support it.
480
481 config HAVE_ARCH_AUDITSYSCALL
482 bool
483
484 config AUDITSYSCALL
485 def_bool y
486 depends on AUDIT && HAVE_ARCH_AUDITSYS
487 select FSNOTIFY
488
489 source "kernel/irq/Kconfig"
490 source "kernel/time/Kconfig"
491 source "kernel/bpf/Kconfig"
492 source "kernel/Kconfig.preempt"
493
494 menu "CPU/Task time and stats accounting"
495
496 config VIRT_CPU_ACCOUNTING
497 bool
498
499 choice
500 prompt "Cputime accounting"
501 default TICK_CPU_ACCOUNTING
502
503 # Kind of a stub config for the pure tick base
504 config TICK_CPU_ACCOUNTING
505 bool "Simple tick based cputime accoun
506 depends on !S390 && !NO_HZ_FULL
507 help
508 This is the basic tick based cputime
509 statistics about user, system and id
510 granularity.
511
512 If unsure, say Y.
513
514 config VIRT_CPU_ACCOUNTING_NATIVE
515 bool "Deterministic task and CPU time
516 depends on HAVE_VIRT_CPU_ACCOUNTING &&
517 select VIRT_CPU_ACCOUNTING
518 help
519 Select this option to enable more ac
520 accounting. This is done by reading
521 kernel entry and exit and on transit
522 between system, softirq and hardirq
523 small performance impact. In the ca
524 this also enables accounting of stol
525 systems.
526
527 config VIRT_CPU_ACCOUNTING_GEN
528 bool "Full dynticks CPU time accountin
529 depends on HAVE_CONTEXT_TRACKING_USER
530 depends on HAVE_VIRT_CPU_ACCOUNTING_GE
531 depends on GENERIC_CLOCKEVENTS
532 select VIRT_CPU_ACCOUNTING
533 select CONTEXT_TRACKING_USER
534 help
535 Select this option to enable task an
536 dynticks systems. This accounting is
537 kernel-user boundaries using the con
538 The accounting is thus performed at
539 overhead.
540
541 For now this is only useful if you a
542 dynticks subsystem development.
543
544 If unsure, say N.
545
546 endchoice
547
548 config IRQ_TIME_ACCOUNTING
549 bool "Fine granularity task level IRQ
550 depends on HAVE_IRQ_TIME_ACCOUNTING &&
551 help
552 Select this option to enable fine gr
553 accounting. This is done by reading
554 transitions between softirq and hard
555 small performance impact.
556
557 If in doubt, say N here.
558
559 config HAVE_SCHED_AVG_IRQ
560 def_bool y
561 depends on IRQ_TIME_ACCOUNTING || PARA
562 depends on SMP
563
564 config SCHED_HW_PRESSURE
565 bool
566 default y if ARM && ARM_CPU_TOPOLOGY
567 default y if ARM64
568 depends on SMP
569 depends on CPU_FREQ_THERMAL
570 help
571 Select this option to enable HW pres
572 scheduler. HW pressure is the value
573 that reflects the reduction in CPU c
574 HW throttling. HW throttling occurs
575 a CPU is capped due to high operatin
576
577 If selected, the scheduler will be a
578 i.e. put less load on throttled CPUs
579
580 This requires the architecture to im
581 arch_update_hw_pressure() and arch_s
582
583 config BSD_PROCESS_ACCT
584 bool "BSD Process Accounting"
585 depends on MULTIUSER
586 help
587 If you say Y here, a user level prog
588 kernel (via a special system call) t
589 information to a file: whenever a pr
590 that process will be appended to the
591 information includes things such as
592 command name, memory usage, controll
593 list is in the struct acct in <file:
594 up to the user level program to do u
595 information. This is generally a go
596
597 config BSD_PROCESS_ACCT_V3
598 bool "BSD Process Accounting version 3
599 depends on BSD_PROCESS_ACCT
600 default n
601 help
602 If you say Y here, the process accou
603 in a new file format that also logs
604 process and its parent. Note that th
605 with previous v0/v1/v2 file formats,
606 for processing it. A preliminary ver
607 at <http://www.gnu.org/software/acct
608
609 config TASKSTATS
610 bool "Export task/process statistics t
611 depends on NET
612 depends on MULTIUSER
613 default n
614 help
615 Export selected statistics for tasks
616 generic netlink interface. Unlike BS
617 statistics are available during the
618 responses to commands. Like BSD acco
619 space on task exit.
620
621 Say N if unsure.
622
623 config TASK_DELAY_ACCT
624 bool "Enable per-task delay accounting
625 depends on TASKSTATS
626 select SCHED_INFO
627 help
628 Collect information on time spent by
629 resources like cpu, synchronous bloc
630 in pages. Such statistics can help i
631 relative to other tasks for cpu, io,
632
633 Say N if unsure.
634
635 config TASK_XACCT
636 bool "Enable extended accounting over
637 depends on TASKSTATS
638 help
639 Collect extended task accounting dat
640 to userland for processing over the
641
642 Say N if unsure.
643
644 config TASK_IO_ACCOUNTING
645 bool "Enable per-task storage I/O acco
646 depends on TASK_XACCT
647 help
648 Collect information on the number of
649 task has caused.
650
651 Say N if unsure.
652
653 config PSI
654 bool "Pressure stall information track
655 select KERNFS
656 help
657 Collect metrics that indicate how ov
658 and IO capacity are in the system.
659
660 If you say Y here, the kernel will c
661 pressure statistics files cpu, memor
662 the share of walltime in which some
663 delayed due to contention of the res
664
665 In kernels with cgroup support, cgro
666 have cpu.pressure, memory.pressure,
667 which aggregate pressure stalls for
668
669 For more details see Documentation/a
670
671 Say N if unsure.
672
673 config PSI_DEFAULT_DISABLED
674 bool "Require boot parameter to enable
675 default n
676 depends on PSI
677 help
678 If set, pressure stall information t
679 per default but can be enabled throu
680 kernel commandline during boot.
681
682 This feature adds some code to the t
683 paths of the scheduler. The overhead
684 common scheduling-intense workloads
685 webservers, memcache), but it does s
686 scheduler stress tests, such as hack
687
688 If you are paranoid and not sure wha
689 used for, say Y.
690
691 Say N if unsure.
692
693 endmenu # "CPU/Task time and stats accounting"
694
695 config CPU_ISOLATION
696 bool "CPU isolation"
697 depends on SMP || COMPILE_TEST
698 default y
699 help
700 Make sure that CPUs running critical
701 any source of "noise" such as unboun
702 Unbound jobs get offloaded to housek
703 the "isolcpus=" boot parameter.
704
705 Say Y if unsure.
706
707 source "kernel/rcu/Kconfig"
708
709 config IKCONFIG
710 tristate "Kernel .config support"
711 help
712 This option enables the complete Lin
713 contents to be saved in the kernel.
714 of which kernel options are used in
715 on-disk kernel. This information ca
716 image file with the script scripts/e
717 input to rebuild the current kernel
718 It can also be extracted from a runn
719 /proc/config.gz if enabled (below).
720
721 config IKCONFIG_PROC
722 bool "Enable access to .config through
723 depends on IKCONFIG && PROC_FS
724 help
725 This option enables access to the ke
726 through /proc/config.gz.
727
728 config IKHEADERS
729 tristate "Enable kernel headers throug
730 depends on SYSFS
731 help
732 This option enables access to the in
733 the build process. These can be used
734 or similar programs. If you build t
735 kheaders.ko is built which can be lo
736
737 config LOG_BUF_SHIFT
738 int "Kernel log buffer size (16 => 64K
739 range 12 25
740 default 17
741 depends on PRINTK
742 help
743 Select the minimal kernel log buffer
744 The final size is affected by LOG_CP
745 parameter, see below. Any higher siz
746 by "log_buf_len" boot parameter.
747
748 Examples:
749 17 => 128 KB
750 16 => 64 KB
751 15 => 32 KB
752 14 => 16 KB
753 13 => 8 KB
754 12 => 4 KB
755
756 config LOG_CPU_MAX_BUF_SHIFT
757 int "CPU kernel log buffer size contri
758 depends on SMP
759 range 0 21
760 default 0 if BASE_SMALL
761 default 12
762 depends on PRINTK
763 help
764 This option allows to increase the d
765 according to the number of CPUs. The
766 of each CPU as a power of 2. The use
767 lines however it might be much more
768 e.g. backtraces.
769
770 The increased size means that a new
771 the original static one is unused. I
772 with more CPUs. Therefore this value
773 contributions is greater than the ha
774 buffer as defined by LOG_BUF_SHIFT.
775 so that more than 16 CPUs are needed
776
777 Also this option is ignored when "lo
778 used as it forces an exact (power of
779
780 The number of possible CPUs is used
781 hotplugging making the computation o
782 scenario while allowing a simple alg
783
784 Examples shift values and their mean
785 17 => 128 KB for each CPU
786 16 => 64 KB for each CPU
787 15 => 32 KB for each CPU
788 14 => 16 KB for each CPU
789 13 => 8 KB for each CPU
790 12 => 4 KB for each CPU
791
792 config PRINTK_INDEX
793 bool "Printk indexing debugfs interfac
794 depends on PRINTK && DEBUG_FS
795 help
796 Add support for indexing of all prin
797 at <debugfs>/printk/index/<module>.
798
799 This can be used as part of maintain
800 /dev/kmsg, as it permits auditing th
801 kernel, allowing detection of cases
802 changed or no longer present.
803
804 There is no additional runtime cost
805
806 #
807 # Architectures with an unreliable sched_clock
808 #
809 config HAVE_UNSTABLE_SCHED_CLOCK
810 bool
811
812 config GENERIC_SCHED_CLOCK
813 bool
814
815 menu "Scheduler features"
816
817 config UCLAMP_TASK
818 bool "Enable utilization clamping for
819 depends on CPU_FREQ_GOV_SCHEDUTIL
820 help
821 This feature enables the scheduler t
822 of each CPU based on RUNNABLE tasks
823
824 With this option, the user can speci
825 utilization allowed for RUNNABLE tas
826 the maximum frequency a task should
827 defines the minimum frequency it sho
828
829 Both min and max utilization clamp v
830 aiming at improving its frequency se
831 enforce or grant any specific bandwi
832
833 If in doubt, say N.
834
835 config UCLAMP_BUCKETS_COUNT
836 int "Number of supported utilization c
837 range 5 20
838 default 5
839 depends on UCLAMP_TASK
840 help
841 Defines the number of clamp buckets
842 will be SCHED_CAPACITY_SCALE/UCLAMP_
843 number of clamp buckets the finer th
844 the precision of clamping aggregatio
845
846 For example, with the minimum config
847 clamp buckets tracking 20% utilizati
848 be refcounted in the [20..39]% bucke
849 effective value to 25%.
850 If a second 30% boosted task should
851 that task will be refcounted in the
852 it will boost the bucket clamp effec
853 The clamp effective value of a bucke
854 (20% in the example above) when ther
855 that bucket.
856
857 An additional boost/capping margin c
858 example above the 25% task will be b
859 CPU. If that should be considered no
860 it's always possible to reduce the m
861 clamp buckets to trade off used memo
862 precision.
863
864 If in doubt, use the default value.
865
866 endmenu
867
868 #
869 # For architectures that want to enable the su
870 # balancing logic:
871 #
872 config ARCH_SUPPORTS_NUMA_BALANCING
873 bool
874
875 #
876 # For architectures that prefer to flush all T
877 # are unmapped instead of sending one IPI per
878 # must provide guarantees on what happens if a
879 # written after the unmap. Details are in mm/r
880 # should_defer_flush. The architecture should
881 # and the refill costs are offset by the savin
882 config ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
883 bool
884
885 config CC_HAS_INT128
886 def_bool !$(cc-option,$(m64-flag) -D__
887
888 config CC_IMPLICIT_FALLTHROUGH
889 string
890 default "-Wimplicit-fallthrough=5" if
891 default "-Wimplicit-fallthrough" if CC
892
893 # Currently, disable gcc-10+ array-bounds glob
894 # It's still broken in gcc-13, so no upper bou
895 config GCC10_NO_ARRAY_BOUNDS
896 def_bool y
897
898 config CC_NO_ARRAY_BOUNDS
899 bool
900 default y if CC_IS_GCC && GCC_VERSION
901
902 # Currently, disable -Wstringop-overflow for G
903 config GCC_NO_STRINGOP_OVERFLOW
904 def_bool y
905
906 config CC_NO_STRINGOP_OVERFLOW
907 bool
908 default y if CC_IS_GCC && GCC_NO_STRIN
909
910 config CC_STRINGOP_OVERFLOW
911 bool
912 default y if CC_IS_GCC && !CC_NO_STRIN
913
914 #
915 # For architectures that know their GCC __int1
916 #
917 config ARCH_SUPPORTS_INT128
918 bool
919
920 # For architectures that (ab)use NUMA to repre
921 # all cpu-local but of different latencies, su
922 #
923 config ARCH_WANT_NUMA_VARIABLE_LOCALITY
924 bool
925
926 config NUMA_BALANCING
927 bool "Memory placement aware NUMA sche
928 depends on ARCH_SUPPORTS_NUMA_BALANCIN
929 depends on !ARCH_WANT_NUMA_VARIABLE_LO
930 depends on SMP && NUMA && MIGRATION &&
931 help
932 This option adds support for automat
933 The mechanism is quite primitive and
934 it has references to the node the ta
935
936 This system will be inactive on UMA
937
938 config NUMA_BALANCING_DEFAULT_ENABLED
939 bool "Automatically enable NUMA aware
940 default y
941 depends on NUMA_BALANCING
942 help
943 If set, automatic NUMA balancing wil
944 machine.
945
946 config SLAB_OBJ_EXT
947 bool
948
949 menuconfig CGROUPS
950 bool "Control Group support"
951 select KERNFS
952 help
953 This option adds support for groupin
954 use with process control subsystems
955 controls or device isolation.
956 See
957 - Documentation/scheduler/sche
958 - Documentation/admin-guide/cg
959 and
960
961 Say N if unsure.
962
963 if CGROUPS
964
965 config PAGE_COUNTER
966 bool
967
968 config CGROUP_FAVOR_DYNMODS
969 bool "Favor dynamic modification laten
970 help
971 This option enables the "favordynmod
972 which reduces the latencies of dynam
973 as task migrations and controller on
974 hot path operations such as forks an
975
976 Say N if unsure.
977
978 config MEMCG
979 bool "Memory controller"
980 select PAGE_COUNTER
981 select EVENTFD
982 select SLAB_OBJ_EXT
983 help
984 Provides control over the memory foo
985
986 config MEMCG_V1
987 bool "Legacy cgroup v1 memory controll
988 depends on MEMCG
989 default n
990 help
991 Legacy cgroup v1 memory controller w
992 cgroup v2 implementation. The v1 is
993 which haven't migrated to the new cg
994 do not have any such application the
995 this option disabled.
996
997 Please note that feature set of the
998 going to shrink due to deprecation p
999 controller are highly discouraged.
1000
1001 Say N if unsure.
1002
1003 config BLK_CGROUP
1004 bool "IO controller"
1005 depends on BLOCK
1006 default n
1007 help
1008 Generic block IO controller cgroup in
1009 cgroup interface which should be used
1010 policies.
1011
1012 Currently, CFQ IO scheduler uses it t
1013 control disk bandwidth allocation (pr
1014 to such task groups. It is also used
1015 block layer to implement upper limit
1016
1017 This option only enables generic Bloc
1018 One needs to also enable actual IO co
1019 enabling proportional weight division
1020 CONFIG_BFQ_GROUP_IOSCHED=y; for enabl
1021 CONFIG_BLK_DEV_THROTTLING=y.
1022
1023 See Documentation/admin-guide/cgroup-
1024
1025 config CGROUP_WRITEBACK
1026 bool
1027 depends on MEMCG && BLK_CGROUP
1028 default y
1029
1030 menuconfig CGROUP_SCHED
1031 bool "CPU controller"
1032 default n
1033 help
1034 This feature lets CPU scheduler rec
1035 bandwidth allocation to such task g
1036 tasks.
1037
1038 if CGROUP_SCHED
1039 config GROUP_SCHED_WEIGHT
1040 def_bool n
1041
1042 config FAIR_GROUP_SCHED
1043 bool "Group scheduling for SCHED_OTHE
1044 depends on CGROUP_SCHED
1045 select GROUP_SCHED_WEIGHT
1046 default CGROUP_SCHED
1047
1048 config CFS_BANDWIDTH
1049 bool "CPU bandwidth provisioning for
1050 depends on FAIR_GROUP_SCHED
1051 default n
1052 help
1053 This option allows users to define
1054 tasks running within the fair group
1055 set are considered to be unconstrai
1056 restriction.
1057 See Documentation/scheduler/sched-b
1058
1059 config RT_GROUP_SCHED
1060 bool "Group scheduling for SCHED_RR/F
1061 depends on CGROUP_SCHED
1062 default n
1063 help
1064 This feature lets you explicitly al
1065 to task groups. If enabled, it will
1066 schedule realtime tasks for non-roo
1067 realtime bandwidth for them.
1068 See Documentation/scheduler/sched-r
1069
1070 config EXT_GROUP_SCHED
1071 bool
1072 depends on SCHED_CLASS_EXT && CGROUP_
1073 select GROUP_SCHED_WEIGHT
1074 default y
1075
1076 endif #CGROUP_SCHED
1077
1078 config SCHED_MM_CID
1079 def_bool y
1080 depends on SMP && RSEQ
1081
1082 config UCLAMP_TASK_GROUP
1083 bool "Utilization clamping per group
1084 depends on CGROUP_SCHED
1085 depends on UCLAMP_TASK
1086 default n
1087 help
1088 This feature enables the scheduler
1089 of each CPU based on RUNNABLE tasks
1090
1091 When this option is enabled, the us
1092 CPU bandwidth which is allowed for
1093 The max bandwidth allows to clamp t
1094 can use, while the min bandwidth al
1095 frequency a task will always use.
1096
1097 When task group based utilization c
1098 specified task-specific clamp value
1099 specified clamp value. Both minimum
1100 be bigger than the corresponding cl
1101
1102 If in doubt, say N.
1103
1104 config CGROUP_PIDS
1105 bool "PIDs controller"
1106 help
1107 Provides enforcement of process num
1108 cgroup. Any attempt to fork more pr
1109 cgroup will fail. PIDs are fundamen
1110 is fairly trivial to reach PID exha
1111 conservative kmemcg limit. As a res
1112 system to halt without being limite
1113 PIDs controller is designed to stop
1114
1115 It should be noted that organisatio
1116 to a cgroup hierarchy) will *not* b
1117 since the PIDs limit only affects a
1118 attach to a cgroup.
1119
1120 config CGROUP_RDMA
1121 bool "RDMA controller"
1122 help
1123 Provides enforcement of RDMA resour
1124 It is fairly easy for consumers to
1125 can result into resource unavailabi
1126 RDMA controller is designed to stop
1127 Attaching processes with active RDM
1128 hierarchy is allowed even if can cr
1129
1130 config CGROUP_FREEZER
1131 bool "Freezer controller"
1132 help
1133 Provides a way to freeze and unfree
1134 cgroup.
1135
1136 This option affects the ORIGINAL cg
1137 controller includes important in-ke
1138
1139 If you're using cgroup2, say N.
1140
1141 config CGROUP_HUGETLB
1142 bool "HugeTLB controller"
1143 depends on HUGETLB_PAGE
1144 select PAGE_COUNTER
1145 default n
1146 help
1147 Provides a cgroup controller for Hu
1148 When you enable this, you can put a
1149 The limit is enforced during page f
1150 support page reclaim, enforcing the
1151 that, the application will get SIGB
1152 HugeTLB pages beyond its limit. Thi
1153 beforehand how much HugeTLB pages i
1154 control group is tracked in the thi
1155 that we cannot use the controller w
1156
1157 config CPUSETS
1158 bool "Cpuset controller"
1159 depends on SMP
1160 help
1161 This option will let you create and
1162 allow dynamically partitioning a sy
1163 Memory Nodes and assigning tasks to
1164 This is primarily useful on large S
1165
1166 Say N if unsure.
1167
1168 config CPUSETS_V1
1169 bool "Legacy cgroup v1 cpusets contro
1170 depends on CPUSETS
1171 default n
1172 help
1173 Legacy cgroup v1 cpusets controller
1174 cgroup v2 implementation. The v1 is
1175 which haven't migrated to the new c
1176 do not have any such application th
1177 this option disabled.
1178
1179 Say N if unsure.
1180
1181 config PROC_PID_CPUSET
1182 bool "Include legacy /proc/<pid>/cpus
1183 depends on CPUSETS
1184 default y
1185
1186 config CGROUP_DEVICE
1187 bool "Device controller"
1188 help
1189 Provides a cgroup controller implem
1190 devices which a process in the cgro
1191
1192 config CGROUP_CPUACCT
1193 bool "Simple CPU accounting controlle
1194 help
1195 Provides a simple controller for mo
1196 total CPU consumed by the tasks in
1197
1198 config CGROUP_PERF
1199 bool "Perf controller"
1200 depends on PERF_EVENTS
1201 help
1202 This option extends the perf per-cp
1203 to threads which belong to the cgro
1204 designated cpu. Or this can be use
1205 so that it can monitor performance
1206
1207 Say N if unsure.
1208
1209 config CGROUP_BPF
1210 bool "Support for eBPF programs attac
1211 depends on BPF_SYSCALL
1212 select SOCK_CGROUP_DATA
1213 help
1214 Allow attaching eBPF programs to a
1215 syscall command BPF_PROG_ATTACH.
1216
1217 In which context these programs are
1218 of attachment. For instance, progra
1219 BPF_CGROUP_INET_INGRESS will be exe
1220 inet sockets.
1221
1222 config CGROUP_MISC
1223 bool "Misc resource controller"
1224 default n
1225 help
1226 Provides a controller for miscellan
1227
1228 Miscellaneous scalar resources are
1229 which cannot be abstracted like the
1230 tracks and limits the miscellaneous
1231 attached to a cgroup hierarchy.
1232
1233 For more information, please check
1234 /Documentation/admin-guide/cgroup-v
1235
1236 config CGROUP_DEBUG
1237 bool "Debug controller"
1238 default n
1239 depends on DEBUG_KERNEL
1240 help
1241 This option enables a simple contro
1242 debugging information about the cgr
1243 controller is for control cgroup de
1244 interfaces are not stable.
1245
1246 Say N.
1247
1248 config SOCK_CGROUP_DATA
1249 bool
1250 default n
1251
1252 endif # CGROUPS
1253
1254 menuconfig NAMESPACES
1255 bool "Namespaces support" if EXPERT
1256 depends on MULTIUSER
1257 default !EXPERT
1258 help
1259 Provides the way to make tasks work
1260 the same id. For example same IPC i
1261 or same user id or pid may refer to
1262 different namespaces.
1263
1264 if NAMESPACES
1265
1266 config UTS_NS
1267 bool "UTS namespace"
1268 default y
1269 help
1270 In this namespace tasks see differe
1271 uname() system call
1272
1273 config TIME_NS
1274 bool "TIME namespace"
1275 depends on GENERIC_VDSO_TIME_NS
1276 default y
1277 help
1278 In this namespace boottime and mono
1279 The time will keep going with the s
1280
1281 config IPC_NS
1282 bool "IPC namespace"
1283 depends on (SYSVIPC || POSIX_MQUEUE)
1284 default y
1285 help
1286 In this namespace tasks work with I
1287 different IPC objects in different
1288
1289 config USER_NS
1290 bool "User namespace"
1291 default n
1292 help
1293 This allows containers, i.e. vserve
1294 to provide different user info for
1295
1296 When user namespaces are enabled in
1297 recommended that the MEMCG option a
1298 user-space use the memory control g
1299 of memory a memory unprivileged use
1300
1301 If unsure, say N.
1302
1303 config PID_NS
1304 bool "PID Namespaces"
1305 default y
1306 help
1307 Support process id namespaces. Thi
1308 processes with the same pid as long
1309 pid namespaces. This is a building
1310
1311 config NET_NS
1312 bool "Network namespace"
1313 depends on NET
1314 default y
1315 help
1316 Allow user space to create what app
1317 of the network stack.
1318
1319 endif # NAMESPACES
1320
1321 config CHECKPOINT_RESTORE
1322 bool "Checkpoint/restore support"
1323 depends on PROC_FS
1324 select PROC_CHILDREN
1325 select KCMP
1326 default n
1327 help
1328 Enables additional kernel features
1329 In particular it adds auxiliary prc
1330 data and heap segment sizes, and a
1331 entries.
1332
1333 If unsure, say N here.
1334
1335 config SCHED_AUTOGROUP
1336 bool "Automatic process group schedul
1337 select CGROUPS
1338 select CGROUP_SCHED
1339 select FAIR_GROUP_SCHED
1340 help
1341 This option optimizes the scheduler
1342 automatically creating and populati
1343 of workloads isolates aggressive CP
1344 desktop applications. Task group a
1345 upon task session.
1346
1347 config RELAY
1348 bool "Kernel->user space relay suppor
1349 select IRQ_WORK
1350 help
1351 This option enables support for rel
1352 certain file systems (such as debug
1353 It is designed to provide an effici
1354 facilities to relay large amounts o
1355 user space.
1356
1357 If unsure, say N.
1358
1359 config BLK_DEV_INITRD
1360 bool "Initial RAM filesystem and RAM
1361 help
1362 The initial RAM filesystem is a ram
1363 boot loader (loadlin or lilo) and t
1364 before the normal boot procedure. I
1365 load modules needed to mount the "r
1366 etc. See <file:Documentation/admin-
1367
1368 If RAM disk support (BLK_DEV_RAM) i
1369 also enables initial RAM disk (init
1370 15 Kbytes (more on some other archi
1371
1372 If unsure say Y.
1373
1374 if BLK_DEV_INITRD
1375
1376 source "usr/Kconfig"
1377
1378 endif
1379
1380 config BOOT_CONFIG
1381 bool "Boot config support"
1382 select BLK_DEV_INITRD if !BOOT_CONFIG
1383 help
1384 Extra boot config allows system adm
1385 complemental extension of kernel cm
1386 The boot config file must be attach
1387 with checksum, size and magic word.
1388 See <file:Documentation/admin-guide
1389
1390 If unsure, say Y.
1391
1392 config BOOT_CONFIG_FORCE
1393 bool "Force unconditional bootconfig
1394 depends on BOOT_CONFIG
1395 default y if BOOT_CONFIG_EMBED
1396 help
1397 With this Kconfig option set, BOOT_
1398 out even when the "bootconfig" kern
1399 In fact, with this Kconfig option s
1400 make the kernel ignore the BOOT_CON
1401 parameters.
1402
1403 If unsure, say N.
1404
1405 config BOOT_CONFIG_EMBED
1406 bool "Embed bootconfig file in the ke
1407 depends on BOOT_CONFIG
1408 help
1409 Embed a bootconfig file given by BO
1410 kernel. Usually, the bootconfig fil
1411 image. But if the system doesn't su
1412 help you by embedding a bootconfig
1413
1414 If unsure, say N.
1415
1416 config BOOT_CONFIG_EMBED_FILE
1417 string "Embedded bootconfig file path
1418 depends on BOOT_CONFIG_EMBED
1419 help
1420 Specify a bootconfig file which wil
1421 This bootconfig will be used if the
1422 bootconfig in the initrd.
1423
1424 config INITRAMFS_PRESERVE_MTIME
1425 bool "Preserve cpio archive mtimes in
1426 default y
1427 help
1428 Each entry in an initramfs cpio arc
1429 enabled, extracted cpio items take
1430 setting deferred until after creati
1431
1432 If unsure, say Y.
1433
1434 choice
1435 prompt "Compiler optimization level"
1436 default CC_OPTIMIZE_FOR_PERFORMANCE
1437
1438 config CC_OPTIMIZE_FOR_PERFORMANCE
1439 bool "Optimize for performance (-O2)"
1440 help
1441 This is the default optimization le
1442 with the "-O2" compiler flag for be
1443 helpful compile-time warnings.
1444
1445 config CC_OPTIMIZE_FOR_SIZE
1446 bool "Optimize for size (-Os)"
1447 help
1448 Choosing this option will pass "-Os
1449 in a smaller kernel.
1450
1451 endchoice
1452
1453 config HAVE_LD_DEAD_CODE_DATA_ELIMINATION
1454 bool
1455 help
1456 This requires that the arch annotat
1457 its external entry points from bein
1458 must also merge .text.*, .data.*, a
1459 output sections. Care must be taken
1460 sections (e.g., '.text.init'). Typi
1461 is used to distinguish them from la
1462
1463 config LD_DEAD_CODE_DATA_ELIMINATION
1464 bool "Dead code and data elimination
1465 depends on HAVE_LD_DEAD_CODE_DATA_ELI
1466 depends on EXPERT
1467 depends on $(cc-option,-ffunction-sec
1468 depends on $(ld-option,--gc-sections)
1469 help
1470 Enable this if you want to do dead
1471 the linker by compiling with -ffunc
1472 and linking with --gc-sections.
1473
1474 This can reduce on disk and in-memo
1475 code and static data, particularly
1476 on small systems. This has the poss
1477 silently broken kernel if the requi
1478 present. This option is not well te
1479 own risk.
1480
1481 config LD_ORPHAN_WARN
1482 def_bool y
1483 depends on ARCH_WANT_LD_ORPHAN_WARN
1484 depends on $(ld-option,--orphan-handl
1485 depends on $(ld-option,--orphan-handl
1486
1487 config LD_ORPHAN_WARN_LEVEL
1488 string
1489 depends on LD_ORPHAN_WARN
1490 default "error" if WERROR
1491 default "warn"
1492
1493 config SYSCTL
1494 bool
1495
1496 config HAVE_UID16
1497 bool
1498
1499 config SYSCTL_EXCEPTION_TRACE
1500 bool
1501 help
1502 Enable support for /proc/sys/debug/
1503
1504 config SYSCTL_ARCH_UNALIGN_NO_WARN
1505 bool
1506 help
1507 Enable support for /proc/sys/kernel
1508 Allows arch to define/use @no_unali
1509 about unaligned access emulation go
1510
1511 config SYSCTL_ARCH_UNALIGN_ALLOW
1512 bool
1513 help
1514 Enable support for /proc/sys/kernel
1515 Allows arches to define/use @unalig
1516 the unaligned access emulation.
1517 see arch/parisc/kernel/unaligned.c
1518
1519 config HAVE_PCSPKR_PLATFORM
1520 bool
1521
1522 menuconfig EXPERT
1523 bool "Configure standard kernel featu
1524 # Unhide debug options, to make the o
1525 select DEBUG_KERNEL
1526 help
1527 This option allows certain base ker
1528 to be disabled or tweaked. This is
1529 environments which can tolerate a "
1530 Only use this if you really know wh
1531
1532 config UID16
1533 bool "Enable 16-bit UID system calls"
1534 depends on HAVE_UID16 && MULTIUSER
1535 default y
1536 help
1537 This enables the legacy 16-bit UID
1538
1539 config MULTIUSER
1540 bool "Multiple users, groups and capa
1541 default y
1542 help
1543 This option enables support for non
1544 capabilities.
1545
1546 If you say N here, all processes wi
1547 possible capabilities. Saying N he
1548 system calls related to UIDs, GIDs,
1549 setgid, and capset.
1550
1551 If unsure, say Y here.
1552
1553 config SGETMASK_SYSCALL
1554 bool "sgetmask/ssetmask syscalls supp
1555 default PARISC || M68K || PPC || MIPS
1556 help
1557 sys_sgetmask and sys_ssetmask are o
1558 no longer supported in libc but sti
1559 architectures.
1560
1561 If unsure, leave the default option
1562
1563 config SYSFS_SYSCALL
1564 bool "Sysfs syscall support" if EXPER
1565 default y
1566 help
1567 sys_sysfs is an obsolete system cal
1568 Note that disabling this option is
1569 compatibility with some systems.
1570
1571 If unsure say Y here.
1572
1573 config FHANDLE
1574 bool "open by fhandle syscalls" if EX
1575 select EXPORTFS
1576 default y
1577 help
1578 If you say Y here, a user level pro
1579 file names to handle and then later
1580 different file system operations. T
1581 userspace file servers, which now t
1582 of names. The handle would remain t
1583 get renamed. Enables open_by_handle
1584 syscalls.
1585
1586 config POSIX_TIMERS
1587 bool "Posix Clocks & timers" if EXPER
1588 default y
1589 help
1590 This includes native support for PO
1591 Some embedded systems have no use f
1592 can be configured out to reduce the
1593
1594 When this option is disabled, the f
1595 available: timer_create, timer_gett
1596 timer_settime, timer_delete, clock_
1597 setitimer, alarm. Furthermore, the
1598 clock_getres and clock_nanosleep sy
1599 CLOCK_REALTIME, CLOCK_MONOTONIC and
1600
1601 If unsure say y.
1602
1603 config PRINTK
1604 default y
1605 bool "Enable support for printk" if E
1606 select IRQ_WORK
1607 help
1608 This option enables normal printk s
1609 eliminates most of the message stri
1610 and makes the kernel more or less s
1611 very difficult to diagnose system p
1612 strongly discouraged.
1613
1614 config BUG
1615 bool "BUG() support" if EXPERT
1616 default y
1617 help
1618 Disabling this option eliminates su
1619 the size of your kernel image and p
1620 numerous fatal conditions. You shou
1621 option for embedded systems with no
1622 Just say Y.
1623
1624 config ELF_CORE
1625 depends on COREDUMP
1626 default y
1627 bool "Enable ELF core dumps" if EXPER
1628 help
1629 Enable support for generating core
1630
1631
1632 config PCSPKR_PLATFORM
1633 bool "Enable PC-Speaker support" if E
1634 depends on HAVE_PCSPKR_PLATFORM
1635 select I8253_LOCK
1636 default y
1637 help
1638 This option allows to disable the i
1639 support, saving some memory.
1640
1641 config BASE_SMALL
1642 bool "Enable smaller-sized data struc
1643 help
1644 Enabling this option reduces the si
1645 kernel data structures. This saves
1646 but may reduce performance.
1647
1648 config FUTEX
1649 bool "Enable futex support" if EXPERT
1650 depends on !(SPARC32 && SMP)
1651 default y
1652 imply RT_MUTEXES
1653 help
1654 Disabling this option will cause th
1655 support for "fast userspace mutexes
1656 run glibc-based applications correc
1657
1658 config FUTEX_PI
1659 bool
1660 depends on FUTEX && RT_MUTEXES
1661 default y
1662
1663 config EPOLL
1664 bool "Enable eventpoll support" if EX
1665 default y
1666 help
1667 Disabling this option will cause th
1668 support for epoll family of system
1669
1670 config SIGNALFD
1671 bool "Enable signalfd() system call"
1672 default y
1673 help
1674 Enable the signalfd() system call t
1675 on a file descriptor.
1676
1677 If unsure, say Y.
1678
1679 config TIMERFD
1680 bool "Enable timerfd() system call" i
1681 default y
1682 help
1683 Enable the timerfd() system call th
1684 events on a file descriptor.
1685
1686 If unsure, say Y.
1687
1688 config EVENTFD
1689 bool "Enable eventfd() system call" i
1690 default y
1691 help
1692 Enable the eventfd() system call th
1693 kernel notification (ie. KAIO) or u
1694
1695 If unsure, say Y.
1696
1697 config SHMEM
1698 bool "Use full shmem filesystem" if E
1699 default y
1700 depends on MMU
1701 help
1702 The shmem is an internal filesystem
1703 It is backed by swap and manages re
1704 to userspace as tmpfs if TMPFS is e
1705 option replaces shmem and tmpfs wit
1706 which may be appropriate on small s
1707
1708 config AIO
1709 bool "Enable AIO support" if EXPERT
1710 default y
1711 help
1712 This option enables POSIX asynchron
1713 by some high performance threaded a
1714 this option saves about 7k.
1715
1716 config IO_URING
1717 bool "Enable IO uring support" if EXP
1718 select IO_WQ
1719 default y
1720 help
1721 This option enables support for the
1722 applications to submit and complete
1723 completion rings that are shared be
1724
1725 config GCOV_PROFILE_URING
1726 bool "Enable GCOV profiling on the io
1727 depends on GCOV_KERNEL
1728 help
1729 Enable GCOV profiling on the io_uri
1730 code coverage testing.
1731
1732 If unsure, say N.
1733
1734 Note that this will have a negative
1735 the io_uring subsystem, hence this
1736 specific test purposes.
1737
1738 config ADVISE_SYSCALLS
1739 bool "Enable madvise/fadvise syscalls
1740 default y
1741 help
1742 This option enables the madvise and
1743 applications to advise the kernel a
1744 usage, improving performance. If bu
1745 applications use these syscalls, yo
1746 space.
1747
1748 config MEMBARRIER
1749 bool "Enable membarrier() system call
1750 default y
1751 help
1752 Enable the membarrier() system call
1753 barriers across all running threads
1754 the cost of user-space memory barri
1755 pairs of memory barriers into pairs
1756 compiler barrier.
1757
1758 If unsure, say Y.
1759
1760 config KCMP
1761 bool "Enable kcmp() system call" if E
1762 help
1763 Enable the kernel resource comparis
1764 user-space with the ability to comp
1765 share a common resource, such as a
1766 memory space.
1767
1768 If unsure, say N.
1769
1770 config RSEQ
1771 bool "Enable rseq() system call" if E
1772 default y
1773 depends on HAVE_RSEQ
1774 select MEMBARRIER
1775 help
1776 Enable the restartable sequences sy
1777 user-space cache for the current CP
1778 speeds up getting the current CPU n
1779 as well as an ABI to speed up user-
1780 per-CPU data.
1781
1782 If unsure, say Y.
1783
1784 config DEBUG_RSEQ
1785 default n
1786 bool "Enable debugging of rseq() syst
1787 depends on RSEQ && DEBUG_KERNEL
1788 help
1789 Enable extra debugging checks for t
1790
1791 If unsure, say N.
1792
1793 config CACHESTAT_SYSCALL
1794 bool "Enable cachestat() system call"
1795 default y
1796 help
1797 Enable the cachestat system call, w
1798 statistics of a file (number of cac
1799 pages marked for writeback, (recent
1800
1801 If unsure say Y here.
1802
1803 config PC104
1804 bool "PC/104 support" if EXPERT
1805 help
1806 Expose PC/104 form factor device dr
1807 selection and configuration. Enable
1808 machine has a PC/104 bus.
1809
1810 config KALLSYMS
1811 bool "Load all symbols for debugging/
1812 default y
1813 help
1814 Say Y here to let the kernel print
1815 symbolic stack backtraces. This inc
1816 somewhat, as all symbols have to be
1817
1818 config KALLSYMS_SELFTEST
1819 bool "Test the basic functions and pe
1820 depends on KALLSYMS
1821 default n
1822 help
1823 Test the basic functions and perfor
1824 kallsyms_lookup_name. It also calcu
1825 kallsyms compression algorithm for
1826
1827 Start self-test automatically after
1828 "dmesg | grep kallsyms_selftest" to
1829 displayed in the last line, indicat
1830
1831 config KALLSYMS_ALL
1832 bool "Include all symbols in kallsyms
1833 depends on DEBUG_KERNEL && KALLSYMS
1834 help
1835 Normally kallsyms only contains the
1836 OOPS messages and backtraces (i.e.,
1837 sections). This is sufficient for m
1838 enable kernel live patching, or oth
1839 when a debugger is used) all symbol
1840 variables from the data sections, e
1841
1842 This option makes sure that all sym
1843 image (i.e., symbols from all secti
1844 size (depending on the kernel confi
1845 something like this).
1846
1847 Say N unless you really need all sy
1848
1849 config KALLSYMS_ABSOLUTE_PERCPU
1850 bool
1851 depends on KALLSYMS
1852 default X86_64 && SMP
1853
1854 # end of the "standard kernel features (exper
1855
1856 config ARCH_HAS_MEMBARRIER_CALLBACKS
1857 bool
1858
1859 config ARCH_HAS_MEMBARRIER_SYNC_CORE
1860 bool
1861
1862 config HAVE_PERF_EVENTS
1863 bool
1864 help
1865 See tools/perf/design.txt for detai
1866
1867 config GUEST_PERF_EVENTS
1868 bool
1869 depends on HAVE_PERF_EVENTS
1870
1871 config PERF_USE_VMALLOC
1872 bool
1873 help
1874 See tools/perf/design.txt for detai
1875
1876 menu "Kernel Performance Events And Counters"
1877
1878 config PERF_EVENTS
1879 bool "Kernel performance events and c
1880 default y if PROFILING
1881 depends on HAVE_PERF_EVENTS
1882 select IRQ_WORK
1883 help
1884 Enable kernel support for various p
1885 by software and hardware.
1886
1887 Software events are supported eithe
1888 use of generic tracepoints.
1889
1890 Most modern CPUs support performanc
1891 counter registers. These registers
1892 types of hw events: such as instruc
1893 suffered, or branches mis-predicted
1894 kernel or applications. These regis
1895 when a threshold number of events h
1896 used to profile the code that runs
1897
1898 The Linux Performance Event subsyst
1899 these software and hardware event c
1900 system call and used by the "perf"
1901 provides per task and per CPU count
1902 capabilities on top of those.
1903
1904 Say Y if unsure.
1905
1906 config DEBUG_PERF_USE_VMALLOC
1907 default n
1908 bool "Debug: use vmalloc to back perf
1909 depends on PERF_EVENTS && DEBUG_KERNE
1910 select PERF_USE_VMALLOC
1911 help
1912 Use vmalloc memory to back perf mma
1913
1914 Mostly useful for debugging the vma
1915 that don't require it.
1916
1917 Say N if unsure.
1918
1919 endmenu
1920
1921 config SYSTEM_DATA_VERIFICATION
1922 def_bool n
1923 select SYSTEM_TRUSTED_KEYRING
1924 select KEYS
1925 select CRYPTO
1926 select CRYPTO_RSA
1927 select ASYMMETRIC_KEY_TYPE
1928 select ASYMMETRIC_PUBLIC_KEY_SUBTYPE
1929 select ASN1
1930 select OID_REGISTRY
1931 select X509_CERTIFICATE_PARSER
1932 select PKCS7_MESSAGE_PARSER
1933 help
1934 Provide PKCS#7 message verification
1935 trusted keyring to provide public k
1936 module verification, kexec image ve
1937 verification.
1938
1939 config PROFILING
1940 bool "Profiling support"
1941 help
1942 Say Y here to enable the extended p
1943 by profilers.
1944
1945 config RUST
1946 bool "Rust support"
1947 depends on HAVE_RUST
1948 depends on RUST_IS_AVAILABLE
1949 depends on !MODVERSIONS
1950 depends on !GCC_PLUGIN_RANDSTRUCT
1951 depends on !RANDSTRUCT
1952 depends on !DEBUG_INFO_BTF || PAHOLE_
1953 depends on !CFI_CLANG || HAVE_CFI_ICA
1954 select CFI_ICALL_NORMALIZE_INTEGERS i
1955 depends on !CALL_PADDING || RUSTC_VER
1956 depends on !KASAN_SW_TAGS
1957 depends on !(MITIGATION_RETHUNK && KA
1958 help
1959 Enables Rust support in the kernel.
1960
1961 This allows other Rust-related opti
1962 to be selected.
1963
1964 It is also required to be able to l
1965 written in Rust.
1966
1967 See Documentation/rust/ for more in
1968
1969 If unsure, say N.
1970
1971 config RUSTC_VERSION_TEXT
1972 string
1973 depends on RUST
1974 default "$(RUSTC_VERSION_TEXT)"
1975 help
1976 See `CC_VERSION_TEXT`.
1977
1978 config BINDGEN_VERSION_TEXT
1979 string
1980 depends on RUST
1981 # The dummy parameter `workaround-for
1982 # (https://github.com/rust-lang/rust-
1983 # the minimum version is upgraded pas
1984 default "$(shell,$(BINDGEN) --version
1985
1986 #
1987 # Place an empty function call at each tracep
1988 # dynamically changed for a probe function.
1989 #
1990 config TRACEPOINTS
1991 bool
1992
1993 source "kernel/Kconfig.kexec"
1994
1995 endmenu # General setup
1996
1997 source "arch/Kconfig"
1998
1999 config RT_MUTEXES
2000 bool
2001 default y if PREEMPT_RT
2002
2003 config MODULE_SIG_FORMAT
2004 def_bool n
2005 select SYSTEM_DATA_VERIFICATION
2006
2007 source "kernel/module/Kconfig"
2008
2009 config INIT_ALL_POSSIBLE
2010 bool
2011 help
2012 Back when each arch used to define
2013 cpu_possible_mask, some of them cho
2014 with all 1s, and others with all 0s
2015 it was better to provide this optio
2016 and have several arch maintainers p
2017
2018 source "block/Kconfig"
2019
2020 config PREEMPT_NOTIFIERS
2021 bool
2022
2023 config PADATA
2024 depends on SMP
2025 bool
2026
2027 config ASN1
2028 tristate
2029 help
2030 Build a simple ASN.1 grammar compil
2031 that can be interpreted by the ASN.
2032 inform it as to what tags are to be
2033 functions to call on what tags.
2034
2035 source "kernel/Kconfig.locks"
2036
2037 config ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
2038 bool
2039
2040 config ARCH_HAS_PREPARE_SYNC_CORE_CMD
2041 bool
2042
2043 config ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
2044 bool
2045
2046 # It may be useful for an architecture to ove
2047 # SYSCALL_DEFINE() and __SYSCALL_DEFINEx() ma
2048 # and the COMPAT_ variants in <linux/compat.h
2049 # different calling convention for syscalls.
2050 # macros for not-implemented syscalls in kern
2051 # kernel/time/posix-stubs.c. All these overri
2052 # <asm/syscall_wrapper.h>.
2053 config ARCH_HAS_SYSCALL_WRAPPER
2054 def_bool n
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