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