linux-6.15/init/Kconfig

1 # SPDX-License-Identifier: GPL-2.0-only
8 	  - Re-run Kconfig when the compiler is updated
13 	  - Ensure full rebuild when the compiler is updated
14 	    include/linux/compiler-version.h contains this option in the comment
16 	    auto-generated dependency. When the compiler is updated, syncconfig
20 	def_bool $(success,test "$(cc-name)" = GCC)
24 	default $(cc-version) if CC_IS_GCC
28 	def_bool $(success,test "$(cc-name)" = Clang)
32 	default $(cc-version) if CC_IS_CLANG
36 	def_bool $(success,test "$(as-name)" = GNU)
39 	def_bool $(success,test "$(as-name)" = LLVM)
45 	default $(as-version)
48 	def_bool $(success,test "$(ld-name)" = BFD)
52 	default $(ld-version) if LD_IS_BFD
56 	def_bool $(success,test "$(ld-name)" = LLD)
60 	default $(ld-version) if LD_IS_LLD
65 	default $(rustc-version)
75 	  Please see Documentation/rust/quick-start.rst for instructions on how
83 	default $(rustc-llvm-version)
87 …default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(CLANG_FLAGS) $(USERCFLAGS) $(USERLDFLA…
88 …default $(success,$(srctree)/scripts/cc-can-link.sh $(CC) $(CLANG_FLAGS) $(USERCFLAGS) $(USERLDFLA…
102 …epends on $(success,echo 'int foo(int x) { asm goto ("": "=r"(x) ::: bar); return x; bar: return 0…
106 	# Detect buggy gcc and clang, fixed in gcc-11 clang-14.
107 …$(success,echo 'int foo(int *x) { asm goto (".long (%l[bar]) - .": "+m"(*x) ::: bar); return *x; b…
110 …env "CC=$(CC)" "LD=$(LD)" "NM=$(NM)" "OBJCOPY=$(OBJCOPY)" $(srctree)/scripts/tools-support-relr.sh)
113 	def_bool $(success,echo 'void foo(void) { asm inline (""); }' | $(CC) -x c - -c -o /dev/null)
116 … '__attribute__((no_profile_instrument_function)) int x();' | $(CC) -x c - -c -o /dev/null -Werror)
121 … __attribute__((__counted_by__(count))); };' | $(CC) $(CLANG_FLAGS) -x c - -c -o /dev/null -Werror)
123 	# https://github.com/llvm/llvm-project/pull/110497
124 	# https://github.com/llvm/llvm-project/pull/112636
128 …[][4] __attribute__((__nonstring__)) = { };' | $(CC) $(CLANG_FLAGS) -x c - -c -o /dev/null -Werror)
132 	# https://github.com/llvm/llvm-project/pull/130661
143 	default $(shell,$(srctree)/scripts/pahole-version.sh $(PAHOLE))
190 	  drivers to compile-test them.
201 	  enables the '-Werror' (for C) and '-Dwarnings' (for Rust) flags
217 	  Compile test headers exported to user-space to ensure they are
218 	  self-contained, i.e. compilable as standalone units.
221 	  headers are self-contained, say Y here. Otherwise, choose N.
224 	string "Local version - append to kernel release"
242 	  A string of the format -gxxxxxxxx will be added to the localversion
243 	  if a git-based tree is found.  The string generated by this will be
250 	    $ git rev-parse --verify HEAD
292 	  The linux kernel is a kind of self-extracting executable.
342 	  filter (i386, x86_64, ARM, ARM64, RISC-V, big endian PowerPC,
362 	  LZ4 is an LZ77-type compressor with a fixed, byte-oriented encoding.
419 	  DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
459 	bool "General notification queue"
463 	  This is a general notification queue for the kernel to pass events to
468 	  See Documentation/core-api/watch_queue.rst
542 	  this also enables accounting of stolen time on logically-partitioned
555 	  kernel-user boundaries using the context tracking subsystem.
642 	bool "Enable per-task delay accounting"
663 	bool "Enable per-task storage I/O accounting"
702 	  common scheduling-intense workloads in practice (such as
733 	  on-disk kernel.  This information can be extracted from the kernel
734 	  image file with the script scripts/extract-ikconfig and used as
750 	  This option enables access to the in-kernel headers that are generated during
753 	  kheaders.ko is built which can be loaded on-demand to get access to headers.
862 	  the precision of clamping aggregation and tracking at run-time.
868 	  If a second 30% boosted task should be co-scheduled on the same CPU,
879 	  clamp buckets to trade off used memory for run-time tracking
887 # For architectures that want to enable the support for NUMA-affine scheduler
904 	def_bool !$(cc-option,$(m64-flag) -D__SIZEOF_INT128__=0) && 64BIT
908 	default "-Wimplicit-fallthrough=5" if CC_IS_GCC && $(cc-option,-Wimplicit-fallthrough=5)
909 	default "-Wimplicit-fallthrough" if CC_IS_CLANG && $(cc-option,-Wunreachable-code-fallthrough)
911 # Currently, disable gcc-10+ array-bounds globally.
912 # It's still broken in gcc-13, so no upper bound yet.
920 # Currently, disable -Wstringop-overflow for GCC globally.
939 # all cpu-local but of different latencies, such as SuperH.
975 		- Documentation/scheduler/sched-design-CFS.rst	(CFS)
976 		- Documentation/admin-guide/cgroup-v1/ (features for grouping, isolation
1041 	See Documentation/admin-guide/cgroup-v1/blkio-controller.rst for more information.
1075 	  See Documentation/scheduler/sched-bwc.rst for more information.
1084 	  schedule realtime tasks for non-root users until you allocate
1086 	  See Documentation/scheduler/sched-rt-group.rst for more information.
1116 	  specified task-specific clamp value is constrained by the cgroup
1165 	  controller includes important in-kernel memory consumers per default.
1232 	  This option extends the perf per-cpu mode to restrict monitoring
1264 	  /Documentation/admin-guide/cgroup-v2.rst.
1328 	  user-space use the memory control groups to limit the amount
1378 	bool "Kernel->user space relay support (formerly relayfs)"
1396 	  etc. See <file:Documentation/admin-guide/initrd.rst> for details.
1418 	  See <file:Documentation/admin-guide/bootconfig.rst> for details.
1428 	  out even when the "bootconfig" kernel-boot parameter is omitted.
1430 	  make the kernel ignore the BOOT_CONFIG-supplied kernel-boot
1469 	  Build KUnit tests for initramfs. See Documentation/dev-tools/kunit
1476 	bool "Optimize for performance (-O2)"
1479 	  with the "-O2" compiler flag for best performance and most
1480 	  helpful compile-time warnings.
1483 	bool "Optimize for size (-Os)"
1485 	  Choosing this option will pass "-Os" to your compiler resulting
1504 	depends on $(cc-option,-ffunction-sections -fdata-sections)
1505 	depends on $(ld-option,--gc-sections)
1508 	  the linker by compiling with -ffunction-sections -fdata-sections,
1509 	  and linking with --gc-sections.
1511 	  This can reduce on disk and in-memory size of the kernel
1521 	depends on $(ld-option,--orphan-handling=warn)
1522 	depends on $(ld-option,--orphan-handling=error)
1539 	  Enable support for /proc/sys/debug/exception-trace.
1544 	  Enable support for /proc/sys/kernel/ignore-unaligned-usertrap
1551 	  Enable support for /proc/sys/kernel/unaligned-trap
1571 	# Unhide debug options, to make the on-by-default options visible
1576 	  environments which can tolerate a "non-standard" kernel.
1580 	bool "Enable 16-bit UID system calls" if EXPERT
1584 	  This enables the legacy 16-bit UID syscall wrappers.
1590 	  This option enables support for non-root users, groups and
1670 	bool "Enable PC-Speaker support" if EXPERT
1675 	  This option allows to disable the internal PC-Speaker
1679 	bool "Enable smaller-sized data structures for core" if EXPERT
1693 	  run glibc-based applications correctly.
1791 	  the cost of user-space memory barriers asymmetrically by transforming
1801 	  user-space with the ability to compare two processes to see if they
1814 	  user-space cache for the current CPU number value, which
1815 	  speeds up getting the current CPU number from user-space,
1816 	  as well as an ABI to speed up user-space operations on
1817 	  per-CPU data.
1864 	  Start self-test automatically after system startup. Suggest executing
1899 	  A 64-bit kernel is required for the memory sealing feature.
1914 	  Documentation/userspace-api/mseal.rst
1941 	  Software events are supported either built-in or via the
1947 	  suffered, or branches mis-predicted - without slowing down the
1949 	  when a threshold number of events have passed - and can thus be
2016 	  This allows other Rust-related options, like drivers written in Rust,
2036 	# The dummy parameter `workaround-for-0.69.0` is required to support 0.69.0
2037 	# (https://github.com/rust-lang/rust-bindgen/pull/2678) and 0.71.0
2038 	# (https://github.com/rust-lang/rust-bindgen/pull/3040). It can be removed
2041 	default "$(shell,$(BINDGEN) --version workaround-for-0.69.0 2>/dev/null)"
2108 # macros for not-implemented syscalls in kernel/sys_ni.c and
2109 # kernel/time/posix-stubs.c. All these overrides need to be available in