1# SPDX-License-Identifier: GPL-2.0 2# 3# General architecture dependent options 4# 5 6# 7# Note: arch/$(SRCARCH)/Kconfig needs to be included first so that it can 8# override the default values in this file. 9# 10source "arch/$(SRCARCH)/Kconfig" 11 12menu "General architecture-dependent options" 13 14config CRASH_CORE 15 bool 16 17config KEXEC_CORE 18 select CRASH_CORE 19 bool 20 21config KEXEC_ELF 22 bool 23 24config HAVE_IMA_KEXEC 25 bool 26 27config ARCH_HAS_SUBPAGE_FAULTS 28 bool 29 help 30 Select if the architecture can check permissions at sub-page 31 granularity (e.g. arm64 MTE). The probe_user_*() functions 32 must be implemented. 33 34config HOTPLUG_SMT 35 bool 36 37config GENERIC_ENTRY 38 bool 39 40config KPROBES 41 bool "Kprobes" 42 depends on MODULES 43 depends on HAVE_KPROBES 44 select KALLSYMS 45 select TASKS_RCU if PREEMPTION 46 help 47 Kprobes allows you to trap at almost any kernel address and 48 execute a callback function. register_kprobe() establishes 49 a probepoint and specifies the callback. Kprobes is useful 50 for kernel debugging, non-intrusive instrumentation and testing. 51 If in doubt, say "N". 52 53config JUMP_LABEL 54 bool "Optimize very unlikely/likely branches" 55 depends on HAVE_ARCH_JUMP_LABEL 56 depends on CC_HAS_ASM_GOTO 57 select OBJTOOL if HAVE_JUMP_LABEL_HACK 58 help 59 This option enables a transparent branch optimization that 60 makes certain almost-always-true or almost-always-false branch 61 conditions even cheaper to execute within the kernel. 62 63 Certain performance-sensitive kernel code, such as trace points, 64 scheduler functionality, networking code and KVM have such 65 branches and include support for this optimization technique. 66 67 If it is detected that the compiler has support for "asm goto", 68 the kernel will compile such branches with just a nop 69 instruction. When the condition flag is toggled to true, the 70 nop will be converted to a jump instruction to execute the 71 conditional block of instructions. 72 73 This technique lowers overhead and stress on the branch prediction 74 of the processor and generally makes the kernel faster. The update 75 of the condition is slower, but those are always very rare. 76 77 ( On 32-bit x86, the necessary options added to the compiler 78 flags may increase the size of the kernel slightly. ) 79 80config STATIC_KEYS_SELFTEST 81 bool "Static key selftest" 82 depends on JUMP_LABEL 83 help 84 Boot time self-test of the branch patching code. 85 86config STATIC_CALL_SELFTEST 87 bool "Static call selftest" 88 depends on HAVE_STATIC_CALL 89 help 90 Boot time self-test of the call patching code. 91 92config OPTPROBES 93 def_bool y 94 depends on KPROBES && HAVE_OPTPROBES 95 select TASKS_RCU if PREEMPTION 96 97config KPROBES_ON_FTRACE 98 def_bool y 99 depends on KPROBES && HAVE_KPROBES_ON_FTRACE 100 depends on DYNAMIC_FTRACE_WITH_REGS 101 help 102 If function tracer is enabled and the arch supports full 103 passing of pt_regs to function tracing, then kprobes can 104 optimize on top of function tracing. 105 106config UPROBES 107 def_bool n 108 depends on ARCH_SUPPORTS_UPROBES 109 help 110 Uprobes is the user-space counterpart to kprobes: they 111 enable instrumentation applications (such as 'perf probe') 112 to establish unintrusive probes in user-space binaries and 113 libraries, by executing handler functions when the probes 114 are hit by user-space applications. 115 116 ( These probes come in the form of single-byte breakpoints, 117 managed by the kernel and kept transparent to the probed 118 application. ) 119 120config HAVE_64BIT_ALIGNED_ACCESS 121 def_bool 64BIT && !HAVE_EFFICIENT_UNALIGNED_ACCESS 122 help 123 Some architectures require 64 bit accesses to be 64 bit 124 aligned, which also requires structs containing 64 bit values 125 to be 64 bit aligned too. This includes some 32 bit 126 architectures which can do 64 bit accesses, as well as 64 bit 127 architectures without unaligned access. 128 129 This symbol should be selected by an architecture if 64 bit 130 accesses are required to be 64 bit aligned in this way even 131 though it is not a 64 bit architecture. 132 133 See Documentation/core-api/unaligned-memory-access.rst for 134 more information on the topic of unaligned memory accesses. 135 136config HAVE_EFFICIENT_UNALIGNED_ACCESS 137 bool 138 help 139 Some architectures are unable to perform unaligned accesses 140 without the use of get_unaligned/put_unaligned. Others are 141 unable to perform such accesses efficiently (e.g. trap on 142 unaligned access and require fixing it up in the exception 143 handler.) 144 145 This symbol should be selected by an architecture if it can 146 perform unaligned accesses efficiently to allow different 147 code paths to be selected for these cases. Some network 148 drivers, for example, could opt to not fix up alignment 149 problems with received packets if doing so would not help 150 much. 151 152 See Documentation/core-api/unaligned-memory-access.rst for more 153 information on the topic of unaligned memory accesses. 154 155config ARCH_USE_BUILTIN_BSWAP 156 bool 157 help 158 Modern versions of GCC (since 4.4) have builtin functions 159 for handling byte-swapping. Using these, instead of the old 160 inline assembler that the architecture code provides in the 161 __arch_bswapXX() macros, allows the compiler to see what's 162 happening and offers more opportunity for optimisation. In 163 particular, the compiler will be able to combine the byteswap 164 with a nearby load or store and use load-and-swap or 165 store-and-swap instructions if the architecture has them. It 166 should almost *never* result in code which is worse than the 167 hand-coded assembler in <asm/swab.h>. But just in case it 168 does, the use of the builtins is optional. 169 170 Any architecture with load-and-swap or store-and-swap 171 instructions should set this. And it shouldn't hurt to set it 172 on architectures that don't have such instructions. 173 174config KRETPROBES 175 def_bool y 176 depends on KPROBES && (HAVE_KRETPROBES || HAVE_RETHOOK) 177 178config KRETPROBE_ON_RETHOOK 179 def_bool y 180 depends on HAVE_RETHOOK 181 depends on KRETPROBES 182 select RETHOOK 183 184config USER_RETURN_NOTIFIER 185 bool 186 depends on HAVE_USER_RETURN_NOTIFIER 187 help 188 Provide a kernel-internal notification when a cpu is about to 189 switch to user mode. 190 191config HAVE_IOREMAP_PROT 192 bool 193 194config HAVE_KPROBES 195 bool 196 197config HAVE_KRETPROBES 198 bool 199 200config HAVE_OPTPROBES 201 bool 202 203config HAVE_KPROBES_ON_FTRACE 204 bool 205 206config ARCH_CORRECT_STACKTRACE_ON_KRETPROBE 207 bool 208 help 209 Since kretprobes modifies return address on the stack, the 210 stacktrace may see the kretprobe trampoline address instead 211 of correct one. If the architecture stacktrace code and 212 unwinder can adjust such entries, select this configuration. 213 214config HAVE_FUNCTION_ERROR_INJECTION 215 bool 216 217config HAVE_NMI 218 bool 219 220config HAVE_FUNCTION_DESCRIPTORS 221 bool 222 223config TRACE_IRQFLAGS_SUPPORT 224 bool 225 226config TRACE_IRQFLAGS_NMI_SUPPORT 227 bool 228 229# 230# An arch should select this if it provides all these things: 231# 232# task_pt_regs() in asm/processor.h or asm/ptrace.h 233# arch_has_single_step() if there is hardware single-step support 234# arch_has_block_step() if there is hardware block-step support 235# asm/syscall.h supplying asm-generic/syscall.h interface 236# linux/regset.h user_regset interfaces 237# CORE_DUMP_USE_REGSET #define'd in linux/elf.h 238# TIF_SYSCALL_TRACE calls ptrace_report_syscall_{entry,exit} 239# TIF_NOTIFY_RESUME calls resume_user_mode_work() 240# 241config HAVE_ARCH_TRACEHOOK 242 bool 243 244config HAVE_DMA_CONTIGUOUS 245 bool 246 247config GENERIC_SMP_IDLE_THREAD 248 bool 249 250config GENERIC_IDLE_POLL_SETUP 251 bool 252 253config ARCH_HAS_FORTIFY_SOURCE 254 bool 255 help 256 An architecture should select this when it can successfully 257 build and run with CONFIG_FORTIFY_SOURCE. 258 259# 260# Select if the arch provides a historic keepinit alias for the retain_initrd 261# command line option 262# 263config ARCH_HAS_KEEPINITRD 264 bool 265 266# Select if arch has all set_memory_ro/rw/x/nx() functions in asm/cacheflush.h 267config ARCH_HAS_SET_MEMORY 268 bool 269 270# Select if arch has all set_direct_map_invalid/default() functions 271config ARCH_HAS_SET_DIRECT_MAP 272 bool 273 274# 275# Select if the architecture provides the arch_dma_set_uncached symbol to 276# either provide an uncached segment alias for a DMA allocation, or 277# to remap the page tables in place. 278# 279config ARCH_HAS_DMA_SET_UNCACHED 280 bool 281 282# 283# Select if the architectures provides the arch_dma_clear_uncached symbol 284# to undo an in-place page table remap for uncached access. 285# 286config ARCH_HAS_DMA_CLEAR_UNCACHED 287 bool 288 289# Select if arch init_task must go in the __init_task_data section 290config ARCH_TASK_STRUCT_ON_STACK 291 bool 292 293# Select if arch has its private alloc_task_struct() function 294config ARCH_TASK_STRUCT_ALLOCATOR 295 bool 296 297config HAVE_ARCH_THREAD_STRUCT_WHITELIST 298 bool 299 depends on !ARCH_TASK_STRUCT_ALLOCATOR 300 help 301 An architecture should select this to provide hardened usercopy 302 knowledge about what region of the thread_struct should be 303 whitelisted for copying to userspace. Normally this is only the 304 FPU registers. Specifically, arch_thread_struct_whitelist() 305 should be implemented. Without this, the entire thread_struct 306 field in task_struct will be left whitelisted. 307 308# Select if arch has its private alloc_thread_stack() function 309config ARCH_THREAD_STACK_ALLOCATOR 310 bool 311 312# Select if arch wants to size task_struct dynamically via arch_task_struct_size: 313config ARCH_WANTS_DYNAMIC_TASK_STRUCT 314 bool 315 316config ARCH_WANTS_NO_INSTR 317 bool 318 help 319 An architecture should select this if the noinstr macro is being used on 320 functions to denote that the toolchain should avoid instrumenting such 321 functions and is required for correctness. 322 323config ARCH_32BIT_OFF_T 324 bool 325 depends on !64BIT 326 help 327 All new 32-bit architectures should have 64-bit off_t type on 328 userspace side which corresponds to the loff_t kernel type. This 329 is the requirement for modern ABIs. Some existing architectures 330 still support 32-bit off_t. This option is enabled for all such 331 architectures explicitly. 332 333# Selected by 64 bit architectures which have a 32 bit f_tinode in struct ustat 334config ARCH_32BIT_USTAT_F_TINODE 335 bool 336 337config HAVE_ASM_MODVERSIONS 338 bool 339 help 340 This symbol should be selected by an architecture if it provides 341 <asm/asm-prototypes.h> to support the module versioning for symbols 342 exported from assembly code. 343 344config HAVE_REGS_AND_STACK_ACCESS_API 345 bool 346 help 347 This symbol should be selected by an architecture if it supports 348 the API needed to access registers and stack entries from pt_regs, 349 declared in asm/ptrace.h 350 For example the kprobes-based event tracer needs this API. 351 352config HAVE_RSEQ 353 bool 354 depends on HAVE_REGS_AND_STACK_ACCESS_API 355 help 356 This symbol should be selected by an architecture if it 357 supports an implementation of restartable sequences. 358 359config HAVE_FUNCTION_ARG_ACCESS_API 360 bool 361 help 362 This symbol should be selected by an architecture if it supports 363 the API needed to access function arguments from pt_regs, 364 declared in asm/ptrace.h 365 366config HAVE_HW_BREAKPOINT 367 bool 368 depends on PERF_EVENTS 369 370config HAVE_MIXED_BREAKPOINTS_REGS 371 bool 372 depends on HAVE_HW_BREAKPOINT 373 help 374 Depending on the arch implementation of hardware breakpoints, 375 some of them have separate registers for data and instruction 376 breakpoints addresses, others have mixed registers to store 377 them but define the access type in a control register. 378 Select this option if your arch implements breakpoints under the 379 latter fashion. 380 381config HAVE_USER_RETURN_NOTIFIER 382 bool 383 384config HAVE_PERF_EVENTS_NMI 385 bool 386 help 387 System hardware can generate an NMI using the perf event 388 subsystem. Also has support for calculating CPU cycle events 389 to determine how many clock cycles in a given period. 390 391config HAVE_HARDLOCKUP_DETECTOR_PERF 392 bool 393 depends on HAVE_PERF_EVENTS_NMI 394 help 395 The arch chooses to use the generic perf-NMI-based hardlockup 396 detector. Must define HAVE_PERF_EVENTS_NMI. 397 398config HAVE_NMI_WATCHDOG 399 depends on HAVE_NMI 400 bool 401 help 402 The arch provides a low level NMI watchdog. It provides 403 asm/nmi.h, and defines its own arch_touch_nmi_watchdog(). 404 405config HAVE_HARDLOCKUP_DETECTOR_ARCH 406 bool 407 select HAVE_NMI_WATCHDOG 408 help 409 The arch chooses to provide its own hardlockup detector, which is 410 a superset of the HAVE_NMI_WATCHDOG. It also conforms to config 411 interfaces and parameters provided by hardlockup detector subsystem. 412 413config HAVE_PERF_REGS 414 bool 415 help 416 Support selective register dumps for perf events. This includes 417 bit-mapping of each registers and a unique architecture id. 418 419config HAVE_PERF_USER_STACK_DUMP 420 bool 421 help 422 Support user stack dumps for perf event samples. This needs 423 access to the user stack pointer which is not unified across 424 architectures. 425 426config HAVE_ARCH_JUMP_LABEL 427 bool 428 429config HAVE_ARCH_JUMP_LABEL_RELATIVE 430 bool 431 432config MMU_GATHER_TABLE_FREE 433 bool 434 435config MMU_GATHER_RCU_TABLE_FREE 436 bool 437 select MMU_GATHER_TABLE_FREE 438 439config MMU_GATHER_PAGE_SIZE 440 bool 441 442config MMU_GATHER_NO_RANGE 443 bool 444 select MMU_GATHER_MERGE_VMAS 445 446config MMU_GATHER_NO_FLUSH_CACHE 447 bool 448 449config MMU_GATHER_MERGE_VMAS 450 bool 451 452config MMU_GATHER_NO_GATHER 453 bool 454 depends on MMU_GATHER_TABLE_FREE 455 456config ARCH_WANT_IRQS_OFF_ACTIVATE_MM 457 bool 458 help 459 Temporary select until all architectures can be converted to have 460 irqs disabled over activate_mm. Architectures that do IPI based TLB 461 shootdowns should enable this. 462 463config ARCH_HAVE_NMI_SAFE_CMPXCHG 464 bool 465 466config HAVE_ALIGNED_STRUCT_PAGE 467 bool 468 help 469 This makes sure that struct pages are double word aligned and that 470 e.g. the SLUB allocator can perform double word atomic operations 471 on a struct page for better performance. However selecting this 472 might increase the size of a struct page by a word. 473 474config HAVE_CMPXCHG_LOCAL 475 bool 476 477config HAVE_CMPXCHG_DOUBLE 478 bool 479 480config ARCH_WEAK_RELEASE_ACQUIRE 481 bool 482 483config ARCH_WANT_IPC_PARSE_VERSION 484 bool 485 486config ARCH_WANT_COMPAT_IPC_PARSE_VERSION 487 bool 488 489config ARCH_WANT_OLD_COMPAT_IPC 490 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION 491 bool 492 493config HAVE_ARCH_SECCOMP 494 bool 495 help 496 An arch should select this symbol to support seccomp mode 1 (the fixed 497 syscall policy), and must provide an overrides for __NR_seccomp_sigreturn, 498 and compat syscalls if the asm-generic/seccomp.h defaults need adjustment: 499 - __NR_seccomp_read_32 500 - __NR_seccomp_write_32 501 - __NR_seccomp_exit_32 502 - __NR_seccomp_sigreturn_32 503 504config HAVE_ARCH_SECCOMP_FILTER 505 bool 506 select HAVE_ARCH_SECCOMP 507 help 508 An arch should select this symbol if it provides all of these things: 509 - all the requirements for HAVE_ARCH_SECCOMP 510 - syscall_get_arch() 511 - syscall_get_arguments() 512 - syscall_rollback() 513 - syscall_set_return_value() 514 - SIGSYS siginfo_t support 515 - secure_computing is called from a ptrace_event()-safe context 516 - secure_computing return value is checked and a return value of -1 517 results in the system call being skipped immediately. 518 - seccomp syscall wired up 519 - if !HAVE_SPARSE_SYSCALL_NR, have SECCOMP_ARCH_NATIVE, 520 SECCOMP_ARCH_NATIVE_NR, SECCOMP_ARCH_NATIVE_NAME defined. If 521 COMPAT is supported, have the SECCOMP_ARCH_COMPAT* defines too. 522 523config SECCOMP 524 prompt "Enable seccomp to safely execute untrusted bytecode" 525 def_bool y 526 depends on HAVE_ARCH_SECCOMP 527 help 528 This kernel feature is useful for number crunching applications 529 that may need to handle untrusted bytecode during their 530 execution. By using pipes or other transports made available 531 to the process as file descriptors supporting the read/write 532 syscalls, it's possible to isolate those applications in their 533 own address space using seccomp. Once seccomp is enabled via 534 prctl(PR_SET_SECCOMP) or the seccomp() syscall, it cannot be 535 disabled and the task is only allowed to execute a few safe 536 syscalls defined by each seccomp mode. 537 538 If unsure, say Y. 539 540config SECCOMP_FILTER 541 def_bool y 542 depends on HAVE_ARCH_SECCOMP_FILTER && SECCOMP && NET 543 help 544 Enable tasks to build secure computing environments defined 545 in terms of Berkeley Packet Filter programs which implement 546 task-defined system call filtering polices. 547 548 See Documentation/userspace-api/seccomp_filter.rst for details. 549 550config SECCOMP_CACHE_DEBUG 551 bool "Show seccomp filter cache status in /proc/pid/seccomp_cache" 552 depends on SECCOMP_FILTER && !HAVE_SPARSE_SYSCALL_NR 553 depends on PROC_FS 554 help 555 This enables the /proc/pid/seccomp_cache interface to monitor 556 seccomp cache data. The file format is subject to change. Reading 557 the file requires CAP_SYS_ADMIN. 558 559 This option is for debugging only. Enabling presents the risk that 560 an adversary may be able to infer the seccomp filter logic. 561 562 If unsure, say N. 563 564config HAVE_ARCH_STACKLEAK 565 bool 566 help 567 An architecture should select this if it has the code which 568 fills the used part of the kernel stack with the STACKLEAK_POISON 569 value before returning from system calls. 570 571config HAVE_STACKPROTECTOR 572 bool 573 help 574 An arch should select this symbol if: 575 - it has implemented a stack canary (e.g. __stack_chk_guard) 576 577config STACKPROTECTOR 578 bool "Stack Protector buffer overflow detection" 579 depends on HAVE_STACKPROTECTOR 580 depends on $(cc-option,-fstack-protector) 581 default y 582 help 583 This option turns on the "stack-protector" GCC feature. This 584 feature puts, at the beginning of functions, a canary value on 585 the stack just before the return address, and validates 586 the value just before actually returning. Stack based buffer 587 overflows (that need to overwrite this return address) now also 588 overwrite the canary, which gets detected and the attack is then 589 neutralized via a kernel panic. 590 591 Functions will have the stack-protector canary logic added if they 592 have an 8-byte or larger character array on the stack. 593 594 This feature requires gcc version 4.2 or above, or a distribution 595 gcc with the feature backported ("-fstack-protector"). 596 597 On an x86 "defconfig" build, this feature adds canary checks to 598 about 3% of all kernel functions, which increases kernel code size 599 by about 0.3%. 600 601config STACKPROTECTOR_STRONG 602 bool "Strong Stack Protector" 603 depends on STACKPROTECTOR 604 depends on $(cc-option,-fstack-protector-strong) 605 default y 606 help 607 Functions will have the stack-protector canary logic added in any 608 of the following conditions: 609 610 - local variable's address used as part of the right hand side of an 611 assignment or function argument 612 - local variable is an array (or union containing an array), 613 regardless of array type or length 614 - uses register local variables 615 616 This feature requires gcc version 4.9 or above, or a distribution 617 gcc with the feature backported ("-fstack-protector-strong"). 618 619 On an x86 "defconfig" build, this feature adds canary checks to 620 about 20% of all kernel functions, which increases the kernel code 621 size by about 2%. 622 623config ARCH_SUPPORTS_SHADOW_CALL_STACK 624 bool 625 help 626 An architecture should select this if it supports the compiler's 627 Shadow Call Stack and implements runtime support for shadow stack 628 switching. 629 630config SHADOW_CALL_STACK 631 bool "Shadow Call Stack" 632 depends on ARCH_SUPPORTS_SHADOW_CALL_STACK 633 depends on DYNAMIC_FTRACE_WITH_REGS || !FUNCTION_GRAPH_TRACER 634 help 635 This option enables the compiler's Shadow Call Stack, which 636 uses a shadow stack to protect function return addresses from 637 being overwritten by an attacker. More information can be found 638 in the compiler's documentation: 639 640 - Clang: https://clang.llvm.org/docs/ShadowCallStack.html 641 - GCC: https://gcc.gnu.org/onlinedocs/gcc/Instrumentation-Options.html#Instrumentation-Options 642 643 Note that security guarantees in the kernel differ from the 644 ones documented for user space. The kernel must store addresses 645 of shadow stacks in memory, which means an attacker capable of 646 reading and writing arbitrary memory may be able to locate them 647 and hijack control flow by modifying the stacks. 648 649config LTO 650 bool 651 help 652 Selected if the kernel will be built using the compiler's LTO feature. 653 654config LTO_CLANG 655 bool 656 select LTO 657 help 658 Selected if the kernel will be built using Clang's LTO feature. 659 660config ARCH_SUPPORTS_LTO_CLANG 661 bool 662 help 663 An architecture should select this option if it supports: 664 - compiling with Clang, 665 - compiling inline assembly with Clang's integrated assembler, 666 - and linking with LLD. 667 668config ARCH_SUPPORTS_LTO_CLANG_THIN 669 bool 670 help 671 An architecture should select this option if it can support Clang's 672 ThinLTO mode. 673 674config HAS_LTO_CLANG 675 def_bool y 676 depends on CC_IS_CLANG && LD_IS_LLD && AS_IS_LLVM 677 depends on $(success,$(NM) --help | head -n 1 | grep -qi llvm) 678 depends on $(success,$(AR) --help | head -n 1 | grep -qi llvm) 679 depends on ARCH_SUPPORTS_LTO_CLANG 680 depends on !FTRACE_MCOUNT_USE_RECORDMCOUNT 681 depends on !KASAN || KASAN_HW_TAGS 682 depends on !GCOV_KERNEL 683 help 684 The compiler and Kconfig options support building with Clang's 685 LTO. 686 687choice 688 prompt "Link Time Optimization (LTO)" 689 default LTO_NONE 690 help 691 This option enables Link Time Optimization (LTO), which allows the 692 compiler to optimize binaries globally. 693 694 If unsure, select LTO_NONE. Note that LTO is very resource-intensive 695 so it's disabled by default. 696 697config LTO_NONE 698 bool "None" 699 help 700 Build the kernel normally, without Link Time Optimization (LTO). 701 702config LTO_CLANG_FULL 703 bool "Clang Full LTO (EXPERIMENTAL)" 704 depends on HAS_LTO_CLANG 705 depends on !COMPILE_TEST 706 select LTO_CLANG 707 help 708 This option enables Clang's full Link Time Optimization (LTO), which 709 allows the compiler to optimize the kernel globally. If you enable 710 this option, the compiler generates LLVM bitcode instead of ELF 711 object files, and the actual compilation from bitcode happens at 712 the LTO link step, which may take several minutes depending on the 713 kernel configuration. More information can be found from LLVM's 714 documentation: 715 716 https://llvm.org/docs/LinkTimeOptimization.html 717 718 During link time, this option can use a large amount of RAM, and 719 may take much longer than the ThinLTO option. 720 721config LTO_CLANG_THIN 722 bool "Clang ThinLTO (EXPERIMENTAL)" 723 depends on HAS_LTO_CLANG && ARCH_SUPPORTS_LTO_CLANG_THIN 724 select LTO_CLANG 725 help 726 This option enables Clang's ThinLTO, which allows for parallel 727 optimization and faster incremental compiles compared to the 728 CONFIG_LTO_CLANG_FULL option. More information can be found 729 from Clang's documentation: 730 731 https://clang.llvm.org/docs/ThinLTO.html 732 733 If unsure, say Y. 734endchoice 735 736config ARCH_SUPPORTS_CFI_CLANG 737 bool 738 help 739 An architecture should select this option if it can support Clang's 740 Control-Flow Integrity (CFI) checking. 741 742config CFI_CLANG 743 bool "Use Clang's Control Flow Integrity (CFI)" 744 depends on LTO_CLANG && ARCH_SUPPORTS_CFI_CLANG 745 depends on CLANG_VERSION >= 140000 746 select KALLSYMS 747 help 748 This option enables Clang’s forward-edge Control Flow Integrity 749 (CFI) checking, where the compiler injects a runtime check to each 750 indirect function call to ensure the target is a valid function with 751 the correct static type. This restricts possible call targets and 752 makes it more difficult for an attacker to exploit bugs that allow 753 the modification of stored function pointers. More information can be 754 found from Clang's documentation: 755 756 https://clang.llvm.org/docs/ControlFlowIntegrity.html 757 758config CFI_CLANG_SHADOW 759 bool "Use CFI shadow to speed up cross-module checks" 760 default y 761 depends on CFI_CLANG && MODULES 762 help 763 If you select this option, the kernel builds a fast look-up table of 764 CFI check functions in loaded modules to reduce performance overhead. 765 766 If unsure, say Y. 767 768config CFI_PERMISSIVE 769 bool "Use CFI in permissive mode" 770 depends on CFI_CLANG 771 help 772 When selected, Control Flow Integrity (CFI) violations result in a 773 warning instead of a kernel panic. This option should only be used 774 for finding indirect call type mismatches during development. 775 776 If unsure, say N. 777 778config HAVE_ARCH_WITHIN_STACK_FRAMES 779 bool 780 help 781 An architecture should select this if it can walk the kernel stack 782 frames to determine if an object is part of either the arguments 783 or local variables (i.e. that it excludes saved return addresses, 784 and similar) by implementing an inline arch_within_stack_frames(), 785 which is used by CONFIG_HARDENED_USERCOPY. 786 787config HAVE_CONTEXT_TRACKING_USER 788 bool 789 help 790 Provide kernel/user boundaries probes necessary for subsystems 791 that need it, such as userspace RCU extended quiescent state. 792 Syscalls need to be wrapped inside user_exit()-user_enter(), either 793 optimized behind static key or through the slow path using TIF_NOHZ 794 flag. Exceptions handlers must be wrapped as well. Irqs are already 795 protected inside ct_irq_enter/ct_irq_exit() but preemption or signal 796 handling on irq exit still need to be protected. 797 798config HAVE_CONTEXT_TRACKING_USER_OFFSTACK 799 bool 800 help 801 Architecture neither relies on exception_enter()/exception_exit() 802 nor on schedule_user(). Also preempt_schedule_notrace() and 803 preempt_schedule_irq() can't be called in a preemptible section 804 while context tracking is CONTEXT_USER. This feature reflects a sane 805 entry implementation where the following requirements are met on 806 critical entry code, ie: before user_exit() or after user_enter(): 807 808 - Critical entry code isn't preemptible (or better yet: 809 not interruptible). 810 - No use of RCU read side critical sections, unless ct_nmi_enter() 811 got called. 812 - No use of instrumentation, unless instrumentation_begin() got 813 called. 814 815config HAVE_TIF_NOHZ 816 bool 817 help 818 Arch relies on TIF_NOHZ and syscall slow path to implement context 819 tracking calls to user_enter()/user_exit(). 820 821config HAVE_VIRT_CPU_ACCOUNTING 822 bool 823 824config HAVE_VIRT_CPU_ACCOUNTING_IDLE 825 bool 826 help 827 Architecture has its own way to account idle CPU time and therefore 828 doesn't implement vtime_account_idle(). 829 830config ARCH_HAS_SCALED_CPUTIME 831 bool 832 833config HAVE_VIRT_CPU_ACCOUNTING_GEN 834 bool 835 default y if 64BIT 836 help 837 With VIRT_CPU_ACCOUNTING_GEN, cputime_t becomes 64-bit. 838 Before enabling this option, arch code must be audited 839 to ensure there are no races in concurrent read/write of 840 cputime_t. For example, reading/writing 64-bit cputime_t on 841 some 32-bit arches may require multiple accesses, so proper 842 locking is needed to protect against concurrent accesses. 843 844config HAVE_IRQ_TIME_ACCOUNTING 845 bool 846 help 847 Archs need to ensure they use a high enough resolution clock to 848 support irq time accounting and then call enable_sched_clock_irqtime(). 849 850config HAVE_MOVE_PUD 851 bool 852 help 853 Architectures that select this are able to move page tables at the 854 PUD level. If there are only 3 page table levels, the move effectively 855 happens at the PGD level. 856 857config HAVE_MOVE_PMD 858 bool 859 help 860 Archs that select this are able to move page tables at the PMD level. 861 862config HAVE_ARCH_TRANSPARENT_HUGEPAGE 863 bool 864 865config HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD 866 bool 867 868config HAVE_ARCH_HUGE_VMAP 869 bool 870 871# 872# Archs that select this would be capable of PMD-sized vmaps (i.e., 873# arch_vmap_pmd_supported() returns true). The VM_ALLOW_HUGE_VMAP flag 874# must be used to enable allocations to use hugepages. 875# 876config HAVE_ARCH_HUGE_VMALLOC 877 depends on HAVE_ARCH_HUGE_VMAP 878 bool 879 880config ARCH_WANT_HUGE_PMD_SHARE 881 bool 882 883config HAVE_ARCH_SOFT_DIRTY 884 bool 885 886config HAVE_MOD_ARCH_SPECIFIC 887 bool 888 help 889 The arch uses struct mod_arch_specific to store data. Many arches 890 just need a simple module loader without arch specific data - those 891 should not enable this. 892 893config MODULES_USE_ELF_RELA 894 bool 895 help 896 Modules only use ELF RELA relocations. Modules with ELF REL 897 relocations will give an error. 898 899config MODULES_USE_ELF_REL 900 bool 901 help 902 Modules only use ELF REL relocations. Modules with ELF RELA 903 relocations will give an error. 904 905config ARCH_WANTS_MODULES_DATA_IN_VMALLOC 906 bool 907 help 908 For architectures like powerpc/32 which have constraints on module 909 allocation and need to allocate module data outside of module area. 910 911config HAVE_IRQ_EXIT_ON_IRQ_STACK 912 bool 913 help 914 Architecture doesn't only execute the irq handler on the irq stack 915 but also irq_exit(). This way we can process softirqs on this irq 916 stack instead of switching to a new one when we call __do_softirq() 917 in the end of an hardirq. 918 This spares a stack switch and improves cache usage on softirq 919 processing. 920 921config HAVE_SOFTIRQ_ON_OWN_STACK 922 bool 923 help 924 Architecture provides a function to run __do_softirq() on a 925 separate stack. 926 927config ALTERNATE_USER_ADDRESS_SPACE 928 bool 929 help 930 Architectures set this when the CPU uses separate address 931 spaces for kernel and user space pointers. In this case, the 932 access_ok() check on a __user pointer is skipped. 933 934config PGTABLE_LEVELS 935 int 936 default 2 937 938config ARCH_HAS_ELF_RANDOMIZE 939 bool 940 help 941 An architecture supports choosing randomized locations for 942 stack, mmap, brk, and ET_DYN. Defined functions: 943 - arch_mmap_rnd() 944 - arch_randomize_brk() 945 946config HAVE_ARCH_MMAP_RND_BITS 947 bool 948 help 949 An arch should select this symbol if it supports setting a variable 950 number of bits for use in establishing the base address for mmap 951 allocations, has MMU enabled and provides values for both: 952 - ARCH_MMAP_RND_BITS_MIN 953 - ARCH_MMAP_RND_BITS_MAX 954 955config HAVE_EXIT_THREAD 956 bool 957 help 958 An architecture implements exit_thread. 959 960config ARCH_MMAP_RND_BITS_MIN 961 int 962 963config ARCH_MMAP_RND_BITS_MAX 964 int 965 966config ARCH_MMAP_RND_BITS_DEFAULT 967 int 968 969config ARCH_MMAP_RND_BITS 970 int "Number of bits to use for ASLR of mmap base address" if EXPERT 971 range ARCH_MMAP_RND_BITS_MIN ARCH_MMAP_RND_BITS_MAX 972 default ARCH_MMAP_RND_BITS_DEFAULT if ARCH_MMAP_RND_BITS_DEFAULT 973 default ARCH_MMAP_RND_BITS_MIN 974 depends on HAVE_ARCH_MMAP_RND_BITS 975 help 976 This value can be used to select the number of bits to use to 977 determine the random offset to the base address of vma regions 978 resulting from mmap allocations. This value will be bounded 979 by the architecture's minimum and maximum supported values. 980 981 This value can be changed after boot using the 982 /proc/sys/vm/mmap_rnd_bits tunable 983 984config HAVE_ARCH_MMAP_RND_COMPAT_BITS 985 bool 986 help 987 An arch should select this symbol if it supports running applications 988 in compatibility mode, supports setting a variable number of bits for 989 use in establishing the base address for mmap allocations, has MMU 990 enabled and provides values for both: 991 - ARCH_MMAP_RND_COMPAT_BITS_MIN 992 - ARCH_MMAP_RND_COMPAT_BITS_MAX 993 994config ARCH_MMAP_RND_COMPAT_BITS_MIN 995 int 996 997config ARCH_MMAP_RND_COMPAT_BITS_MAX 998 int 999 1000config ARCH_MMAP_RND_COMPAT_BITS_DEFAULT 1001 int 1002 1003config ARCH_MMAP_RND_COMPAT_BITS 1004 int "Number of bits to use for ASLR of mmap base address for compatible applications" if EXPERT 1005 range ARCH_MMAP_RND_COMPAT_BITS_MIN ARCH_MMAP_RND_COMPAT_BITS_MAX 1006 default ARCH_MMAP_RND_COMPAT_BITS_DEFAULT if ARCH_MMAP_RND_COMPAT_BITS_DEFAULT 1007 default ARCH_MMAP_RND_COMPAT_BITS_MIN 1008 depends on HAVE_ARCH_MMAP_RND_COMPAT_BITS 1009 help 1010 This value can be used to select the number of bits to use to 1011 determine the random offset to the base address of vma regions 1012 resulting from mmap allocations for compatible applications This 1013 value will be bounded by the architecture's minimum and maximum 1014 supported values. 1015 1016 This value can be changed after boot using the 1017 /proc/sys/vm/mmap_rnd_compat_bits tunable 1018 1019config HAVE_ARCH_COMPAT_MMAP_BASES 1020 bool 1021 help 1022 This allows 64bit applications to invoke 32-bit mmap() syscall 1023 and vice-versa 32-bit applications to call 64-bit mmap(). 1024 Required for applications doing different bitness syscalls. 1025 1026config PAGE_SIZE_LESS_THAN_64KB 1027 def_bool y 1028 depends on !ARM64_64K_PAGES 1029 depends on !IA64_PAGE_SIZE_64KB 1030 depends on !PAGE_SIZE_64KB 1031 depends on !PARISC_PAGE_SIZE_64KB 1032 depends on PAGE_SIZE_LESS_THAN_256KB 1033 1034config PAGE_SIZE_LESS_THAN_256KB 1035 def_bool y 1036 depends on !PAGE_SIZE_256KB 1037 1038# This allows to use a set of generic functions to determine mmap base 1039# address by giving priority to top-down scheme only if the process 1040# is not in legacy mode (compat task, unlimited stack size or 1041# sysctl_legacy_va_layout). 1042# Architecture that selects this option can provide its own version of: 1043# - STACK_RND_MASK 1044config ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT 1045 bool 1046 depends on MMU 1047 select ARCH_HAS_ELF_RANDOMIZE 1048 1049config HAVE_OBJTOOL 1050 bool 1051 1052config HAVE_JUMP_LABEL_HACK 1053 bool 1054 1055config HAVE_NOINSTR_HACK 1056 bool 1057 1058config HAVE_NOINSTR_VALIDATION 1059 bool 1060 1061config HAVE_UACCESS_VALIDATION 1062 bool 1063 select OBJTOOL 1064 1065config HAVE_STACK_VALIDATION 1066 bool 1067 help 1068 Architecture supports objtool compile-time frame pointer rule 1069 validation. 1070 1071config HAVE_RELIABLE_STACKTRACE 1072 bool 1073 help 1074 Architecture has either save_stack_trace_tsk_reliable() or 1075 arch_stack_walk_reliable() function which only returns a stack trace 1076 if it can guarantee the trace is reliable. 1077 1078config HAVE_ARCH_HASH 1079 bool 1080 default n 1081 help 1082 If this is set, the architecture provides an <asm/hash.h> 1083 file which provides platform-specific implementations of some 1084 functions in <linux/hash.h> or fs/namei.c. 1085 1086config HAVE_ARCH_NVRAM_OPS 1087 bool 1088 1089config ISA_BUS_API 1090 def_bool ISA 1091 1092# 1093# ABI hall of shame 1094# 1095config CLONE_BACKWARDS 1096 bool 1097 help 1098 Architecture has tls passed as the 4th argument of clone(2), 1099 not the 5th one. 1100 1101config CLONE_BACKWARDS2 1102 bool 1103 help 1104 Architecture has the first two arguments of clone(2) swapped. 1105 1106config CLONE_BACKWARDS3 1107 bool 1108 help 1109 Architecture has tls passed as the 3rd argument of clone(2), 1110 not the 5th one. 1111 1112config ODD_RT_SIGACTION 1113 bool 1114 help 1115 Architecture has unusual rt_sigaction(2) arguments 1116 1117config OLD_SIGSUSPEND 1118 bool 1119 help 1120 Architecture has old sigsuspend(2) syscall, of one-argument variety 1121 1122config OLD_SIGSUSPEND3 1123 bool 1124 help 1125 Even weirder antique ABI - three-argument sigsuspend(2) 1126 1127config OLD_SIGACTION 1128 bool 1129 help 1130 Architecture has old sigaction(2) syscall. Nope, not the same 1131 as OLD_SIGSUSPEND | OLD_SIGSUSPEND3 - alpha has sigsuspend(2), 1132 but fairly different variant of sigaction(2), thanks to OSF/1 1133 compatibility... 1134 1135config COMPAT_OLD_SIGACTION 1136 bool 1137 1138config COMPAT_32BIT_TIME 1139 bool "Provide system calls for 32-bit time_t" 1140 default !64BIT || COMPAT 1141 help 1142 This enables 32 bit time_t support in addition to 64 bit time_t support. 1143 This is relevant on all 32-bit architectures, and 64-bit architectures 1144 as part of compat syscall handling. 1145 1146config ARCH_NO_PREEMPT 1147 bool 1148 1149config ARCH_EPHEMERAL_INODES 1150 def_bool n 1151 help 1152 An arch should select this symbol if it doesn't keep track of inode 1153 instances on its own, but instead relies on something else (e.g. the 1154 host kernel for an UML kernel). 1155 1156config ARCH_SUPPORTS_RT 1157 bool 1158 1159config CPU_NO_EFFICIENT_FFS 1160 def_bool n 1161 1162config HAVE_ARCH_VMAP_STACK 1163 def_bool n 1164 help 1165 An arch should select this symbol if it can support kernel stacks 1166 in vmalloc space. This means: 1167 1168 - vmalloc space must be large enough to hold many kernel stacks. 1169 This may rule out many 32-bit architectures. 1170 1171 - Stacks in vmalloc space need to work reliably. For example, if 1172 vmap page tables are created on demand, either this mechanism 1173 needs to work while the stack points to a virtual address with 1174 unpopulated page tables or arch code (switch_to() and switch_mm(), 1175 most likely) needs to ensure that the stack's page table entries 1176 are populated before running on a possibly unpopulated stack. 1177 1178 - If the stack overflows into a guard page, something reasonable 1179 should happen. The definition of "reasonable" is flexible, but 1180 instantly rebooting without logging anything would be unfriendly. 1181 1182config VMAP_STACK 1183 default y 1184 bool "Use a virtually-mapped stack" 1185 depends on HAVE_ARCH_VMAP_STACK 1186 depends on !KASAN || KASAN_HW_TAGS || KASAN_VMALLOC 1187 help 1188 Enable this if you want the use virtually-mapped kernel stacks 1189 with guard pages. This causes kernel stack overflows to be 1190 caught immediately rather than causing difficult-to-diagnose 1191 corruption. 1192 1193 To use this with software KASAN modes, the architecture must support 1194 backing virtual mappings with real shadow memory, and KASAN_VMALLOC 1195 must be enabled. 1196 1197config HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 1198 def_bool n 1199 help 1200 An arch should select this symbol if it can support kernel stack 1201 offset randomization with calls to add_random_kstack_offset() 1202 during syscall entry and choose_random_kstack_offset() during 1203 syscall exit. Careful removal of -fstack-protector-strong and 1204 -fstack-protector should also be applied to the entry code and 1205 closely examined, as the artificial stack bump looks like an array 1206 to the compiler, so it will attempt to add canary checks regardless 1207 of the static branch state. 1208 1209config RANDOMIZE_KSTACK_OFFSET 1210 bool "Support for randomizing kernel stack offset on syscall entry" if EXPERT 1211 default y 1212 depends on HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 1213 depends on INIT_STACK_NONE || !CC_IS_CLANG || CLANG_VERSION >= 140000 1214 help 1215 The kernel stack offset can be randomized (after pt_regs) by 1216 roughly 5 bits of entropy, frustrating memory corruption 1217 attacks that depend on stack address determinism or 1218 cross-syscall address exposures. 1219 1220 The feature is controlled via the "randomize_kstack_offset=on/off" 1221 kernel boot param, and if turned off has zero overhead due to its use 1222 of static branches (see JUMP_LABEL). 1223 1224 If unsure, say Y. 1225 1226config RANDOMIZE_KSTACK_OFFSET_DEFAULT 1227 bool "Default state of kernel stack offset randomization" 1228 depends on RANDOMIZE_KSTACK_OFFSET 1229 help 1230 Kernel stack offset randomization is controlled by kernel boot param 1231 "randomize_kstack_offset=on/off", and this config chooses the default 1232 boot state. 1233 1234config ARCH_OPTIONAL_KERNEL_RWX 1235 def_bool n 1236 1237config ARCH_OPTIONAL_KERNEL_RWX_DEFAULT 1238 def_bool n 1239 1240config ARCH_HAS_STRICT_KERNEL_RWX 1241 def_bool n 1242 1243config STRICT_KERNEL_RWX 1244 bool "Make kernel text and rodata read-only" if ARCH_OPTIONAL_KERNEL_RWX 1245 depends on ARCH_HAS_STRICT_KERNEL_RWX 1246 default !ARCH_OPTIONAL_KERNEL_RWX || ARCH_OPTIONAL_KERNEL_RWX_DEFAULT 1247 help 1248 If this is set, kernel text and rodata memory will be made read-only, 1249 and non-text memory will be made non-executable. This provides 1250 protection against certain security exploits (e.g. executing the heap 1251 or modifying text) 1252 1253 These features are considered standard security practice these days. 1254 You should say Y here in almost all cases. 1255 1256config ARCH_HAS_STRICT_MODULE_RWX 1257 def_bool n 1258 1259config STRICT_MODULE_RWX 1260 bool "Set loadable kernel module data as NX and text as RO" if ARCH_OPTIONAL_KERNEL_RWX 1261 depends on ARCH_HAS_STRICT_MODULE_RWX && MODULES 1262 default !ARCH_OPTIONAL_KERNEL_RWX || ARCH_OPTIONAL_KERNEL_RWX_DEFAULT 1263 help 1264 If this is set, module text and rodata memory will be made read-only, 1265 and non-text memory will be made non-executable. This provides 1266 protection against certain security exploits (e.g. writing to text) 1267 1268# select if the architecture provides an asm/dma-direct.h header 1269config ARCH_HAS_PHYS_TO_DMA 1270 bool 1271 1272config HAVE_ARCH_COMPILER_H 1273 bool 1274 help 1275 An architecture can select this if it provides an 1276 asm/compiler.h header that should be included after 1277 linux/compiler-*.h in order to override macro definitions that those 1278 headers generally provide. 1279 1280config HAVE_ARCH_PREL32_RELOCATIONS 1281 bool 1282 help 1283 May be selected by an architecture if it supports place-relative 1284 32-bit relocations, both in the toolchain and in the module loader, 1285 in which case relative references can be used in special sections 1286 for PCI fixup, initcalls etc which are only half the size on 64 bit 1287 architectures, and don't require runtime relocation on relocatable 1288 kernels. 1289 1290config ARCH_USE_MEMREMAP_PROT 1291 bool 1292 1293config LOCK_EVENT_COUNTS 1294 bool "Locking event counts collection" 1295 depends on DEBUG_FS 1296 help 1297 Enable light-weight counting of various locking related events 1298 in the system with minimal performance impact. This reduces 1299 the chance of application behavior change because of timing 1300 differences. The counts are reported via debugfs. 1301 1302# Select if the architecture has support for applying RELR relocations. 1303config ARCH_HAS_RELR 1304 bool 1305 1306config RELR 1307 bool "Use RELR relocation packing" 1308 depends on ARCH_HAS_RELR && TOOLS_SUPPORT_RELR 1309 default y 1310 help 1311 Store the kernel's dynamic relocations in the RELR relocation packing 1312 format. Requires a compatible linker (LLD supports this feature), as 1313 well as compatible NM and OBJCOPY utilities (llvm-nm and llvm-objcopy 1314 are compatible). 1315 1316config ARCH_HAS_MEM_ENCRYPT 1317 bool 1318 1319config ARCH_HAS_CC_PLATFORM 1320 bool 1321 1322config HAVE_SPARSE_SYSCALL_NR 1323 bool 1324 help 1325 An architecture should select this if its syscall numbering is sparse 1326 to save space. For example, MIPS architecture has a syscall array with 1327 entries at 4000, 5000 and 6000 locations. This option turns on syscall 1328 related optimizations for a given architecture. 1329 1330config ARCH_HAS_VDSO_DATA 1331 bool 1332 1333config HAVE_STATIC_CALL 1334 bool 1335 1336config HAVE_STATIC_CALL_INLINE 1337 bool 1338 depends on HAVE_STATIC_CALL 1339 select OBJTOOL 1340 1341config HAVE_PREEMPT_DYNAMIC 1342 bool 1343 1344config HAVE_PREEMPT_DYNAMIC_CALL 1345 bool 1346 depends on HAVE_STATIC_CALL 1347 select HAVE_PREEMPT_DYNAMIC 1348 help 1349 An architecture should select this if it can handle the preemption 1350 model being selected at boot time using static calls. 1351 1352 Where an architecture selects HAVE_STATIC_CALL_INLINE, any call to a 1353 preemption function will be patched directly. 1354 1355 Where an architecture does not select HAVE_STATIC_CALL_INLINE, any 1356 call to a preemption function will go through a trampoline, and the 1357 trampoline will be patched. 1358 1359 It is strongly advised to support inline static call to avoid any 1360 overhead. 1361 1362config HAVE_PREEMPT_DYNAMIC_KEY 1363 bool 1364 depends on HAVE_ARCH_JUMP_LABEL && CC_HAS_ASM_GOTO 1365 select HAVE_PREEMPT_DYNAMIC 1366 help 1367 An architecture should select this if it can handle the preemption 1368 model being selected at boot time using static keys. 1369 1370 Each preemption function will be given an early return based on a 1371 static key. This should have slightly lower overhead than non-inline 1372 static calls, as this effectively inlines each trampoline into the 1373 start of its callee. This may avoid redundant work, and may 1374 integrate better with CFI schemes. 1375 1376 This will have greater overhead than using inline static calls as 1377 the call to the preemption function cannot be entirely elided. 1378 1379config ARCH_WANT_LD_ORPHAN_WARN 1380 bool 1381 help 1382 An arch should select this symbol once all linker sections are explicitly 1383 included, size-asserted, or discarded in the linker scripts. This is 1384 important because we never want expected sections to be placed heuristically 1385 by the linker, since the locations of such sections can change between linker 1386 versions. 1387 1388config HAVE_ARCH_PFN_VALID 1389 bool 1390 1391config ARCH_SUPPORTS_DEBUG_PAGEALLOC 1392 bool 1393 1394config ARCH_SUPPORTS_PAGE_TABLE_CHECK 1395 bool 1396 1397config ARCH_SPLIT_ARG64 1398 bool 1399 help 1400 If a 32-bit architecture requires 64-bit arguments to be split into 1401 pairs of 32-bit arguments, select this option. 1402 1403config ARCH_HAS_ELFCORE_COMPAT 1404 bool 1405 1406config ARCH_HAS_PARANOID_L1D_FLUSH 1407 bool 1408 1409config ARCH_HAVE_TRACE_MMIO_ACCESS 1410 bool 1411 1412config DYNAMIC_SIGFRAME 1413 bool 1414 1415# Select, if arch has a named attribute group bound to NUMA device nodes. 1416config HAVE_ARCH_NODE_DEV_GROUP 1417 bool 1418 1419source "kernel/gcov/Kconfig" 1420 1421source "scripts/gcc-plugins/Kconfig" 1422 1423endmenu 1424