Lines Matching +full:processor +full:- +full:intensive
1 # SPDX-License-Identifier: GPL-2.0
12 menu "General architecture-dependent options"
77 for kernel debugging, non-intrusive instrumentation and testing.
86 makes certain almost-always-true or almost-always-false branch
89 Certain performance-sensitive kernel code, such as trace points,
100 of the processor and generally makes the kernel faster. The update
103 ( On 32-bit x86, the necessary options added to the compiler
110 Boot time self-test of the branch patching code.
116 Boot time self-test of the call patching code.
136 Uprobes is the user-space counterpart to kprobes: they
138 to establish unintrusive probes in user-space binaries and
140 are hit by user-space applications.
142 ( These probes come in the form of single-byte breakpoints,
159 See Documentation/unaligned-memory-access.txt for more
178 See Documentation/core-api/unaligned-memory-access.rst for more
185 for handling byte-swapping. Using these, instead of the old
190 with a nearby load or store and use load-and-swap or
191 store-and-swap instructions if the architecture has them. It
193 hand-coded assembler in <asm/swab.h>. But just in case it
196 Any architecture with load-and-swap or store-and-swap
208 Provide a kernel-internal notification when a cpu is about to
235 # task_pt_regs() in asm/processor.h or asm/ptrace.h
236 # arch_has_single_step() if there is hardware single-step support
237 # arch_has_block_step() if there is hardware block-step support
238 # asm/syscall.h supplying asm-generic/syscall.h interface
288 # to undo an in-place page table remap for uncached access.
327 All new 32-bit architectures should have 64-bit off_t type on
330 still support 32-bit off_t. This option is enabled for all such
337 <asm/asm-prototypes.h> to support the module versioning for symbols
346 For example the kprobes-based event tracer needs this API.
391 The arch chooses to use the generic perf-NMI-based hardlockup
413 bit-mapping of each registers and a unique architecture id.
487 and compat syscalls if the asm-generic/seccomp.h defaults need adjustment:
488 - __NR_seccomp_read_32
489 - __NR_seccomp_write_32
490 - __NR_seccomp_exit_32
491 - __NR_seccomp_sigreturn_32
498 - all the requirements for HAVE_ARCH_SECCOMP
499 - syscall_get_arch()
500 - syscall_get_arguments()
501 - syscall_rollback()
502 - syscall_set_return_value()
503 - SIGSYS siginfo_t support
504 - secure_computing is called from a ptrace_event()-safe context
505 - secure_computing return value is checked and a return value of -1
507 - seccomp syscall wired up
532 task-defined system call filtering polices.
534 See Documentation/userspace-api/seccomp_filter.rst for details.
547 - it has implemented a stack canary (e.g. __stack_chk_guard)
552 depends on $(cc-option,-fstack-protector)
555 This option turns on the "stack-protector" GCC feature. This
563 Functions will have the stack-protector canary logic added if they
564 have an 8-byte or larger character array on the stack.
567 gcc with the feature backported ("-fstack-protector").
576 depends on $(cc-option,-fstack-protector-strong)
579 Functions will have the stack-protector canary logic added in any
582 - local variable's address used as part of the right hand side of an
584 - local variable is an array (or union containing an array),
586 - uses register local variables
589 gcc with the feature backported ("-fstack-protector-strong").
635 - compiling with Clang,
636 - compiling inline assembly with Clang's integrated assembler,
637 - and linking with LLD.
649 depends on $(success,test $(LLVM_IAS) -eq 1)
650 depends on $(success,$(NM) --help | head -n 1 | grep -qi llvm)
651 depends on $(success,$(AR) --help | head -n 1 | grep -qi llvm)
667 If unsure, select LTO_NONE. Note that LTO is very resource-intensive
713 Control-Flow Integrity (CFI) checking.
719 # - https://bugs.llvm.org/show_bug.cgi?id=46258
720 # - https://bugs.llvm.org/show_bug.cgi?id=47479
724 This option enables Clang’s forward-edge Control Flow Integrity
735 bool "Use CFI shadow to speed up cross-module checks"
739 If you select this option, the kernel builds a fast look-up table of
768 Syscalls need to be wrapped inside user_exit()-user_enter(), either
790 With VIRT_CPU_ACCOUNTING_GEN, cputime_t becomes 64-bit.
793 cputime_t. For example, reading/writing 64-bit cputime_t on
794 some 32-bit arches may require multiple accesses, so proper
828 just need a simple module loader without arch specific data - those
862 - arch_mmap_rnd()
863 - arch_randomize_brk()
871 - ARCH_MMAP_RND_BITS_MIN
872 - ARCH_MMAP_RND_BITS_MAX
910 - ARCH_MMAP_RND_COMPAT_BITS_MIN
911 - ARCH_MMAP_RND_COMPAT_BITS_MAX
941 This allows 64bit applications to invoke 32-bit mmap() syscall
942 and vice-versa 32-bit applications to call 64-bit mmap().
946 # address by giving priority to top-down scheme only if the process
950 # - STACK_RND_MASK
960 performs compile-time stack metadata validation.
974 file which provides platform-specific implementations of some
1011 Architecture has old sigsuspend(2) syscall, of one-argument variety
1016 Even weirder antique ABI - three-argument sigsuspend(2)
1022 as OLD_SIGSUSPEND | OLD_SIGSUSPEND3 - alpha has sigsuspend(2),
1030 bool "Provide system calls for 32-bit time_t"
1034 This is relevant on all 32-bit architectures, and 64-bit architectures
1052 - vmalloc space must be large enough to hold many kernel stacks.
1053 This may rule out many 32-bit architectures.
1055 - Stacks in vmalloc space need to work reliably. For example, if
1062 - If the stack overflows into a guard page, something reasonable
1068 bool "Use a virtually-mapped stack"
1072 Enable this if you want the use virtually-mapped kernel stacks
1074 caught immediately rather than causing difficult-to-diagnose
1091 bool "Make kernel text and rodata read-only" if ARCH_OPTIONAL_KERNEL_RWX
1095 If this is set, kernel text and rodata memory will be made read-only,
1096 and non-text memory will be made non-executable. This provides
1111 If this is set, module text and rodata memory will be made read-only,
1112 and non-text memory will be made non-executable. This provides
1115 # select if the architecture provides an asm/dma-direct.h header
1124 linux/compiler-*.h in order to override macro definitions that those
1130 May be selected by an architecture if it supports place-relative
1131 32-bit relocations, both in the toolchain and in the module loader,
1144 Enable light-weight counting of various locking related events
1160 well as compatible NM and OBJCOPY utilities (llvm-nm and llvm-objcopy
1191 included, size-asserted, or discarded in the linker scripts. This is
1199 If a 32-bit architecture requires 64-bit arguments to be split into
1200 pairs of 32-bit arguments, select this option.
1204 source "scripts/gcc-plugins/Kconfig"