blob: 349e59b2f0e3af7383f24ae216a4b06028183244 [file] [log] [blame]
Greg Kroah-Hartmanb2441312017-11-01 15:07:57 +01001# SPDX-License-Identifier: GPL-2.0
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01002# Select 32 or 64 bit
3config 64BIT
Masahiro Yamada104daea2018-05-28 18:21:40 +09004 bool "64-bit kernel" if "$(ARCH)" = "x86"
5 default "$(ARCH)" != "i386"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09006 help
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01007 Say yes to build a 64-bit kernel - formerly known as x86_64
8 Say no to build a 32-bit kernel - formerly known as i386
9
10config X86_32
Jan Beulich3120e252012-09-10 12:41:45 +010011 def_bool y
12 depends on !64BIT
Ingo Molnar341c7872016-11-15 10:04:55 +010013 # Options that are inherently 32-bit kernel only:
14 select ARCH_WANT_IPC_PARSE_VERSION
15 select CLKSRC_I8253
16 select CLONE_BACKWARDS
Thomas Gleixner157e1182020-11-03 10:27:20 +010017 select GENERIC_VDSO_32
Thomas Gleixner117ed452019-04-14 18:00:08 +020018 select HAVE_DEBUG_STACKOVERFLOW
Thomas Gleixner157e1182020-11-03 10:27:20 +010019 select KMAP_LOCAL
Ingo Molnar341c7872016-11-15 10:04:55 +010020 select MODULES_USE_ELF_REL
21 select OLD_SIGACTION
Brian Gerst2ca408d2020-11-30 17:30:59 -050022 select ARCH_SPLIT_ARG64
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +010023
24config X86_64
Jan Beulich3120e252012-09-10 12:41:45 +010025 def_bool y
26 depends on 64BIT
Ingo Molnard94e0682016-11-15 10:11:57 +010027 # Options that are inherently 64-bit kernel only:
Alexandre Ghiti4eb07162019-05-13 17:19:04 -070028 select ARCH_HAS_GIGANTIC_PAGE
Ard Biesheuvelc12d3362019-11-08 13:22:27 +010029 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
Ingo Molnard94e0682016-11-15 10:11:57 +010030 select ARCH_USE_CMPXCHG_LOCKREF
31 select HAVE_ARCH_SOFT_DIRTY
32 select MODULES_USE_ELF_RELA
Christoph Hellwigf616ab52018-05-09 06:53:49 +020033 select NEED_DMA_MAP_STATE
Christoph Hellwig09230cb2018-04-24 09:00:54 +020034 select SWIOTLB
Al Viro7facdc42020-06-13 23:03:25 -040035 select ARCH_HAS_ELFCORE_COMPAT
Kefeng Wang63703f32021-06-30 18:52:20 -070036 select ZONE_DMA32
Sam Ravnborg1032c0b2007-11-06 21:35:08 +010037
Steven Rostedt (VMware)518049d2019-05-10 12:05:46 -040038config FORCE_DYNAMIC_FTRACE
39 def_bool y
40 depends on X86_32
41 depends on FUNCTION_TRACER
42 select DYNAMIC_FTRACE
43 help
44 We keep the static function tracing (!DYNAMIC_FTRACE) around
45 in order to test the non static function tracing in the
46 generic code, as other architectures still use it. But we
47 only need to keep it around for x86_64. No need to keep it
48 for x86_32. For x86_32, force DYNAMIC_FTRACE.
Ingo Molnard94e0682016-11-15 10:11:57 +010049#
50# Arch settings
51#
52# ( Note that options that are marked 'if X86_64' could in principle be
53# ported to 32-bit as well. )
54#
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +010055config X86
Harvey Harrison3c2362e2008-01-30 13:31:03 +010056 def_bool y
Ingo Molnarc763ea22016-11-15 10:26:39 +010057 #
58 # Note: keep this list sorted alphabetically
59 #
Ingo Molnar6471b822015-06-03 10:00:13 +020060 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
61 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
Yury Norov942fa982018-05-16 11:18:49 +030062 select ARCH_32BIT_OFF_T if X86_32
Thomas Gleixner2a21ad52018-09-17 14:45:35 +020063 select ARCH_CLOCKSOURCE_INIT
Anshuman Khandual1e866972021-05-04 18:38:21 -070064 select ARCH_ENABLE_HUGEPAGE_MIGRATION if X86_64 && HUGETLB_PAGE && MIGRATION
Anshuman Khandual91024b32021-05-04 18:38:17 -070065 select ARCH_ENABLE_MEMORY_HOTPLUG if X86_64 || (X86_32 && HIGHMEM)
66 select ARCH_ENABLE_MEMORY_HOTREMOVE if MEMORY_HOTPLUG
Anshuman Khandualcebc7742021-06-30 18:51:58 -070067 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if (PGTABLE_LEVELS > 2) && (X86_64 || X86_PAE)
Anshuman Khandual1e866972021-05-04 18:38:21 -070068 select ARCH_ENABLE_THP_MIGRATION if X86_64 && TRANSPARENT_HUGEPAGE
Ingo Molnarc763ea22016-11-15 10:26:39 +010069 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
Anshuman Khandualc2280be2021-05-04 18:38:09 -070070 select ARCH_HAS_CACHE_LINE_SIZE
Laura Abbottfa5b6ec2017-01-10 13:35:40 -080071 select ARCH_HAS_DEBUG_VIRTUAL
Anshuman Khandual399145f2020-06-04 16:47:15 -070072 select ARCH_HAS_DEBUG_VM_PGTABLE if !X86_PAE
Dan Williams21266be2015-11-19 18:19:29 -080073 select ARCH_HAS_DEVMEM_IS_ALLOWED
Douglas Andersonb1a57bb2020-05-07 13:08:42 -070074 select ARCH_HAS_EARLY_DEBUG if KGDB
Ingo Molnar6471b822015-06-03 10:00:13 +020075 select ARCH_HAS_ELF_RANDOMIZE
Linus Torvalds72d93102014-09-13 11:14:53 -070076 select ARCH_HAS_FAST_MULTIPLIER
Dave Hansen316d0972018-04-20 15:20:28 -070077 select ARCH_HAS_FILTER_PGPROT
Daniel Micay6974f0c2017-07-12 14:36:10 -070078 select ARCH_HAS_FORTIFY_SOURCE
Riku Voipio957e3fa2014-12-12 16:57:44 -080079 select ARCH_HAS_GCOV_PROFILE_ALL
Peter Zijlstra0f1441b2020-06-12 16:05:26 +020080 select ARCH_HAS_KCOV if X86_64 && STACK_VALIDATION
Thiago Jung Bauermann0c9c1d52019-08-06 01:49:14 -030081 select ARCH_HAS_MEM_ENCRYPT
Mathieu Desnoyers10bcc802018-01-29 15:20:18 -050082 select ARCH_HAS_MEMBARRIER_SYNC_CORE
Daniel Borkmann0ebeea82020-05-15 12:11:16 +020083 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
Ingo Molnarc763ea22016-11-15 10:26:39 +010084 select ARCH_HAS_PMEM_API if X86_64
Robin Murphy17596732019-07-16 16:30:47 -070085 select ARCH_HAS_PTE_DEVMAP if X86_64
Laurent Dufour3010a5e2018-06-07 17:06:08 -070086 select ARCH_HAS_PTE_SPECIAL
Dan Williams0aed55a2017-05-29 12:22:50 -070087 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Dan Williamsec6347b2020-10-05 20:40:16 -070088 select ARCH_HAS_COPY_MC if X86_64
Daniel Borkmannd2852a22017-02-21 16:09:33 +010089 select ARCH_HAS_SET_MEMORY
Rick Edgecombed253ca02019-04-25 17:11:34 -070090 select ARCH_HAS_SET_DIRECT_MAP
Laura Abbottad21fc42017-02-06 16:31:57 -080091 select ARCH_HAS_STRICT_KERNEL_RWX
92 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050093 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Brian Gerst25c619e2020-03-13 15:51:42 -040094 select ARCH_HAS_SYSCALL_WRAPPER
Andrey Ryabininc6d30852016-01-20 15:00:55 -080095 select ARCH_HAS_UBSAN_SANITIZE_ALL
Zong Li7e01ccb2020-06-03 16:03:58 -070096 select ARCH_HAS_DEBUG_WX
Kefeng Wang63703f32021-06-30 18:52:20 -070097 select ARCH_HAS_ZONE_DMA_SET if EXPERT
Ingo Molnar6471b822015-06-03 10:00:13 +020098 select ARCH_HAVE_NMI_SAFE_CMPXCHG
99 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -0400100 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -0800101 select ARCH_MIGHT_HAVE_PC_SERIO
Thomas Gleixner3599fe12019-04-25 11:45:22 +0200102 select ARCH_STACKWALK
Arnd Bergmann2c870e62018-07-24 11:48:45 +0200103 select ARCH_SUPPORTS_ACPI
Ingo Molnar6471b822015-06-03 10:00:13 +0200104 select ARCH_SUPPORTS_ATOMIC_RMW
Mike Rapoport5d6ad662020-12-14 19:10:30 -0800105 select ARCH_SUPPORTS_DEBUG_PAGEALLOC
Ingo Molnar6471b822015-06-03 10:00:13 +0200106 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
Thomas Gleixner14df3262020-11-18 20:48:41 +0100107 select ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP if NR_CPUS <= 4096
Nathan Chancellor583bfd42021-04-29 16:26:12 -0700108 select ARCH_SUPPORTS_LTO_CLANG
109 select ARCH_SUPPORTS_LTO_CLANG_THIN
Ingo Molnar6471b822015-06-03 10:00:13 +0200110 select ARCH_USE_BUILTIN_BSWAP
Anshuman Khandualdce44562021-04-29 22:55:15 -0700111 select ARCH_USE_MEMTEST
Ingo Molnar6471b822015-06-03 10:00:13 +0200112 select ARCH_USE_QUEUED_RWLOCKS
113 select ARCH_USE_QUEUED_SPINLOCKS
Mark Brown2ce0d7f2020-04-16 19:24:02 +0100114 select ARCH_USE_SYM_ANNOTATIONS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -0700115 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Daniel Borkmann81c22042019-12-09 16:08:03 +0100116 select ARCH_WANT_DEFAULT_BPF_JIT if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100117 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Nick Desaulniers51c2ee62021-06-21 16:18:22 -0700118 select ARCH_WANTS_NO_INSTR
Alexandre Ghiti3876d4a2019-06-27 15:00:11 -0700119 select ARCH_WANT_HUGE_PMD_SHARE
Nathan Chancellor59612b22020-11-19 13:46:56 -0700120 select ARCH_WANT_LD_ORPHAN_WARN
Huang Ying38d8b4e2017-07-06 15:37:18 -0700121 select ARCH_WANTS_THP_SWAP if X86_64
Balbir Singhb5f06f62021-04-26 21:42:30 +0200122 select ARCH_HAS_PARANOID_L1D_FLUSH
Shile Zhang10916702019-12-04 08:46:31 +0800123 select BUILDTIME_TABLE_SORT
Ingo Molnar6471b822015-06-03 10:00:13 +0200124 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +0200125 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
126 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +0200127 select DCACHE_WORD_ACCESS
Linus Torvalds45471cd2015-06-24 19:52:06 -0700128 select EDAC_ATOMIC_SCRUB
129 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +0200130 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
131 select GENERIC_CLOCKEVENTS_MIN_ADJUST
132 select GENERIC_CMOS_UPDATE
133 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +0100134 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +0200135 select GENERIC_EARLY_IOREMAP
Thomas Gleixner27d6b4d2020-07-23 00:00:04 +0200136 select GENERIC_ENTRY
Ingo Molnar6471b822015-06-03 10:00:13 +0200137 select GENERIC_FIND_FIRST_BIT
138 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +0200139 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +0200140 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +0200141 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200142 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200143 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200144 select GENERIC_IRQ_SHOW
145 select GENERIC_PENDING_IRQ if SMP
Steven Price2ae27132020-02-03 17:36:24 -0800146 select GENERIC_PTDUMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200147 select GENERIC_SMP_IDLE_THREAD
Ingo Molnar6471b822015-06-03 10:00:13 +0200148 select GENERIC_TIME_VSYSCALL
Vincenzo Frascino7ac87072019-06-21 10:52:49 +0100149 select GENERIC_GETTIMEOFDAY
Dmitry Safonov550a77a2019-11-12 01:27:11 +0000150 select GENERIC_VDSO_TIME_NS
Christoph Hellwig39656e82019-07-11 20:56:49 -0700151 select GUP_GET_PTE_LOW_HIGH if X86_PAE
Hans de Goede17e58882020-01-23 22:02:42 +0100152 select HARDIRQS_SW_RESEND
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200153 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200154 select HAVE_ACPI_APEI if ACPI
155 select HAVE_ACPI_APEI_NMI if ACPI
156 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200157 select HAVE_ARCH_AUDITSYSCALL
158 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
159 select HAVE_ARCH_JUMP_LABEL
Ard Biesheuvelb34006c2018-09-18 23:51:41 -0700160 select HAVE_ARCH_JUMP_LABEL_RELATIVE
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800161 select HAVE_ARCH_KASAN if X86_64
Daniel Axtens0609ae02019-11-30 17:55:00 -0800162 select HAVE_ARCH_KASAN_VMALLOC if X86_64
Alexander Potapenko1dc0da62021-02-25 17:18:57 -0800163 select HAVE_ARCH_KFENCE
Ingo Molnar6471b822015-06-03 10:00:13 +0200164 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800165 select HAVE_ARCH_MMAP_RND_BITS if MMU
166 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300167 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ard Biesheuvel271ca782018-08-21 21:56:00 -0700168 select HAVE_ARCH_PREL32_RELOCATIONS
Ingo Molnar6471b822015-06-03 10:00:13 +0200169 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700170 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Alexander Popovafaef012018-08-17 01:16:58 +0300171 select HAVE_ARCH_STACKLEAK
Ingo Molnar6471b822015-06-03 10:00:13 +0200172 select HAVE_ARCH_TRACEHOOK
173 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Matthew Wilcoxa00cc7d2017-02-24 14:57:02 -0800174 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
Peter Xub64d8d12020-04-20 18:13:45 -0700175 select HAVE_ARCH_USERFAULTFD_WP if X86_64 && USERFAULTFD
Axel Rasmussen7677f7f2021-05-04 18:35:36 -0700176 select HAVE_ARCH_USERFAULTFD_MINOR if X86_64 && USERFAULTFD
Andy Lutomirskie37e43a2016-08-11 02:35:23 -0700177 select HAVE_ARCH_VMAP_STACK if X86_64
Kees Cookfe950f62021-04-01 16:23:45 -0700178 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
Ingo Molnarc763ea22016-11-15 10:26:39 +0100179 select HAVE_ARCH_WITHIN_STACK_FRAMES
Masahiro Yamada2ff2b7e2019-08-19 14:54:20 +0900180 select HAVE_ASM_MODVERSIONS
Ingo Molnar6471b822015-06-03 10:00:13 +0200181 select HAVE_CMPXCHG_DOUBLE
182 select HAVE_CMPXCHG_LOCAL
183 select HAVE_CONTEXT_TRACKING if X86_64
Frederic Weisbeckerd1f250e2020-11-17 16:16:37 +0100184 select HAVE_CONTEXT_TRACKING_OFFSTACK if HAVE_CONTEXT_TRACKING
Ingo Molnar6471b822015-06-03 10:00:13 +0200185 select HAVE_C_RECORDMCOUNT
Sami Tolvanen6dafca92020-08-06 15:15:02 -0700186 select HAVE_OBJTOOL_MCOUNT if STACK_VALIDATION
Ingo Molnar6471b822015-06-03 10:00:13 +0200187 select HAVE_DEBUG_KMEMLEAK
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700188 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400189 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900190 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Steven Rostedt (VMware)02a474c2020-10-27 10:55:55 -0400191 select HAVE_DYNAMIC_FTRACE_WITH_ARGS if X86_64
Steven Rostedt (VMware)562955f2019-11-08 13:11:39 -0500192 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
Wang YanQing03f57812018-05-03 14:10:43 +0800193 select HAVE_EBPF_JIT
Johannes Berg58340a02008-07-25 01:45:33 -0700194 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Christoph Hellwig6630a8e2018-11-15 20:05:37 +0100195 select HAVE_EISA
Jiri Slaby5f56a5d2016-05-20 17:00:16 -0700196 select HAVE_EXIT_THREAD
Christoph Hellwig67a929e2019-07-11 20:57:14 -0700197 select HAVE_FAST_GUP
Steven Rostedt (VMware)644e0e82017-03-23 10:33:52 -0400198 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
Ingo Molnar6471b822015-06-03 10:00:13 +0200199 select HAVE_FTRACE_MCOUNT_RECORD
Ingo Molnar6471b822015-06-03 10:00:13 +0200200 select HAVE_FUNCTION_GRAPH_TRACER
201 select HAVE_FUNCTION_TRACER
Emese Revfy6b90bd42016-05-24 00:09:38 +0200202 select HAVE_GCC_PLUGINS
K.Prasad0067f122009-06-01 23:43:57 +0530203 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200204 select HAVE_IOREMAP_PROT
Thomas Gleixner624db9e2021-02-10 00:40:51 +0100205 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200206 select HAVE_IRQ_TIME_ACCOUNTING
207 select HAVE_KERNEL_BZIP2
208 select HAVE_KERNEL_GZIP
209 select HAVE_KERNEL_LZ4
210 select HAVE_KERNEL_LZMA
211 select HAVE_KERNEL_LZO
212 select HAVE_KERNEL_XZ
Nick Terrellfb46d052020-07-30 12:08:39 -0700213 select HAVE_KERNEL_ZSTD
Ingo Molnar6471b822015-06-03 10:00:13 +0200214 select HAVE_KPROBES
215 select HAVE_KPROBES_ON_FTRACE
Masami Hiramatsu540adea2018-01-13 02:55:03 +0900216 select HAVE_FUNCTION_ERROR_INJECTION
Ingo Molnar6471b822015-06-03 10:00:13 +0200217 select HAVE_KRETPROBES
218 select HAVE_KVM
219 select HAVE_LIVEPATCH if X86_64
Frederic Weisbecker01027522010-04-11 18:55:56 +0200220 select HAVE_MIXED_BREAKPOINTS_REGS
Josh Poimboeufee9f8fc2017-07-24 18:36:57 -0500221 select HAVE_MOD_ARCH_SPECIFIC
Joel Fernandes (Google)9f132f72019-01-03 15:28:41 -0800222 select HAVE_MOVE_PMD
Kalesh Singhbe37c982020-12-14 19:07:40 -0800223 select HAVE_MOVE_PUD
Petr Mladek42a0bb32016-05-20 17:00:33 -0700224 select HAVE_NMI
Ingo Molnar6471b822015-06-03 10:00:13 +0200225 select HAVE_OPTPROBES
226 select HAVE_PCSPKR_PLATFORM
227 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200228 select HAVE_PERF_EVENTS_NMI
Nicholas Piggin92e5aae2017-08-18 15:15:51 -0700229 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
Christoph Hellwigeb01d422018-11-15 20:05:32 +0100230 select HAVE_PCI
Jiri Olsac5e63192012-08-07 15:20:36 +0200231 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200232 select HAVE_PERF_USER_STACK_DUMP
Peter Zijlstraff2e6d722020-02-03 17:37:02 -0800233 select MMU_GATHER_RCU_TABLE_FREE if PARAVIRT
Thomas Gleixner00998082020-07-30 12:14:07 +0200234 select HAVE_POSIX_CPU_TIMERS_TASK_WORK
Ingo Molnar6471b822015-06-03 10:00:13 +0200235 select HAVE_REGS_AND_STACK_ACCESS_API
Jiri Slaby6415b382018-05-18 08:47:13 +0200236 select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION
Masami Hiramatsu3c88ee194c2018-04-25 21:20:57 +0900237 select HAVE_FUNCTION_ARG_ACCESS_API
Thomas Gleixnercd1a41c2021-02-10 00:40:52 +0100238 select HAVE_SOFTIRQ_ON_OWN_STACK
Masahiro Yamadad148eac2018-06-14 19:36:45 +0900239 select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
Ingo Molnarc763ea22016-11-15 10:26:39 +0100240 select HAVE_STACK_VALIDATION if X86_64
Josh Poimboeufe6d6c072020-08-18 15:57:44 +0200241 select HAVE_STATIC_CALL
Josh Poimboeuf1e7e4782020-08-18 15:57:45 +0200242 select HAVE_STATIC_CALL_INLINE if HAVE_STACK_VALIDATION
Michal Hocko6ef869e2021-01-18 15:12:19 +0100243 select HAVE_PREEMPT_DYNAMIC
Mathieu Desnoyersd6761b82018-06-02 08:43:58 -0400244 select HAVE_RSEQ
Ingo Molnar6471b822015-06-03 10:00:13 +0200245 select HAVE_SYSCALL_TRACEPOINTS
Ingo Molnar6471b822015-06-03 10:00:13 +0200246 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300247 select HAVE_USER_RETURN_NOTIFIER
Vincenzo Frascino7ac87072019-06-21 10:52:49 +0100248 select HAVE_GENERIC_VDSO
Thomas Gleixner05736e42018-05-29 17:48:27 +0200249 select HOTPLUG_SMT if SMP
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100250 select IRQ_FORCED_THREADING
Christoph Hellwig86596f02018-04-05 09:44:52 +0200251 select NEED_SG_DMA_LENGTH
Christoph Hellwig2eac9c22018-11-15 20:05:33 +0100252 select PCI_DOMAINS if PCI
Sinan Kaya625210c2019-01-21 23:19:58 +0000253 select PCI_LOCKLESS_CONFIG if PCI
Ingo Molnar6471b822015-06-03 10:00:13 +0200254 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500255 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200256 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200257 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500258 select SRCU
Josh Poimboeuf1e7e4782020-08-18 15:57:45 +0200259 select STACK_VALIDATION if HAVE_STACK_VALIDATION && (HAVE_STATIC_CALL_INLINE || RETPOLINE)
Ingo Molnar6471b822015-06-03 10:00:13 +0200260 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700261 select THREAD_INFO_IN_TASK
Masahiro Yamada4aae6832021-07-31 14:22:32 +0900262 select TRACE_IRQFLAGS_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +0200263 select USER_STACKTRACE_SUPPORT
264 select VIRT_TO_BUS
Ingo Molnar3b02a052020-04-13 09:44:39 +0200265 select HAVE_ARCH_KCSAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200266 select X86_FEATURE_NAMES if PROC_FS
Aubrey Li0c608da2019-06-06 09:22:35 +0800267 select PROC_PID_ARCH_STATUS if PROC_FS
Nayna Jain9e2b4be2020-03-08 20:57:51 -0400268 imply IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI
Balbir Singh7d8330a2008-02-10 12:46:28 +0530269
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200270config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100271 def_bool y
272 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200273
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700274config OUTPUT_FORMAT
275 string
276 default "elf32-i386" if X86_32
277 default "elf64-x86-64" if X86_64
278
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100279config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100280 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100281
282config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100283 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100284
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100285config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100286 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100287
Daniel Cashman9e08f572016-01-14 15:20:06 -0800288config ARCH_MMAP_RND_BITS_MIN
289 default 28 if 64BIT
290 default 8
291
292config ARCH_MMAP_RND_BITS_MAX
293 default 32 if 64BIT
294 default 16
295
296config ARCH_MMAP_RND_COMPAT_BITS_MIN
297 default 8
298
299config ARCH_MMAP_RND_COMPAT_BITS_MAX
300 default 16
301
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100302config SBUS
303 bool
304
305config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100306 def_bool y
307 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100308
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100309config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100310 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100311 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000312 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
313
314config GENERIC_BUG_RELATIVE_POINTERS
315 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100316
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100317config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100318 def_bool y
319 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100320
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100321config GENERIC_CALIBRATE_DELAY
322 def_bool y
323
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800324config ARCH_HAS_CPU_RELAX
325 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100326
Dave Hansen316d0972018-04-20 15:20:28 -0700327config ARCH_HAS_FILTER_PGPROT
328 def_bool y
329
Mike Travisdd5af902008-01-30 13:33:32 +0100330config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900331 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100332
Tejun Heo08fc4582009-08-14 15:00:49 +0900333config NEED_PER_CPU_EMBED_FIRST_CHUNK
334 def_bool y
335
336config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900337 def_bool y
338
Johannes Berg801e4062007-12-08 02:12:39 +0100339config ARCH_HIBERNATION_POSSIBLE
340 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100341
Andy Shevchenkod7109fe2021-08-26 18:03:17 +0300342config ARCH_NR_GPIO
343 int
344 default 1024 if X86_64
345 default 512
346
Johannes Bergf4cb5702007-12-08 02:14:00 +0100347config ARCH_SUSPEND_POSSIBLE
348 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100349
Steve Capper53313b22013-04-30 08:03:42 +0100350config ARCH_WANT_GENERAL_HUGETLB
351 def_bool y
352
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100353config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000354 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100355
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300356config KASAN_SHADOW_OFFSET
357 hex
358 depends on KASAN
359 default 0xdffffc0000000000
360
Shane Wang69575d32009-09-01 18:25:07 -0700361config HAVE_INTEL_TXT
362 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700363 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700364
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100365config X86_32_SMP
366 def_bool y
367 depends on X86_32 && SMP
368
369config X86_64_SMP
370 def_bool y
371 depends on X86_64 && SMP
372
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530373config ARCH_SUPPORTS_UPROBES
374 def_bool y
375
Rob Herringd20642f2014-04-18 17:19:54 -0500376config FIX_EARLYCON_MEM
377 def_bool y
378
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +0300379config DYNAMIC_PHYSICAL_MASK
380 bool
381
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700382config PGTABLE_LEVELS
383 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300384 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700385 default 4 if X86_64
386 default 3 if X86_PAE
387 default 2
388
Masahiro Yamada2a61f472018-05-28 18:22:00 +0900389config CC_HAS_SANE_STACKPROTECTOR
390 bool
391 default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
392 default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
393 help
394 We have to make sure stack protector is unconditionally disabled if
Andy Lutomirski3fb0fdb2021-02-13 11:19:44 -0800395 the compiler produces broken code or if it does not let us control
396 the segment on 32-bit kernels.
Masahiro Yamada2a61f472018-05-28 18:22:00 +0900397
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100398menu "Processor type and features"
399
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100400config SMP
401 bool "Symmetric multi-processing support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900402 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100403 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800404 a system with only one CPU, say N. If you have a system with more
405 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100406
Robert Graffham4a474152014-01-23 15:55:29 -0800407 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100408 machines, but will use only one CPU of a multiprocessor machine. If
409 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800410 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100411 will run faster if you say N here.
412
413 Note that if you say Y here and choose architecture "586" or
414 "Pentium" under "Processor family", the kernel will not work on 486
415 architectures. Similarly, multiprocessor kernels for the "PPro"
416 architecture may not work on all Pentium based boards.
417
418 People using multiprocessor machines who say Y here should also say
419 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
420 Management" code will be disabled if you say Y here.
421
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -0300422 See also <file:Documentation/x86/i386/IO-APIC.rst>,
Mauro Carvalho Chehab4f4cfa62019-06-27 14:56:51 -0300423 <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100424 <http://www.tldp.org/docs.html#howto>.
425
426 If you don't know what to do here, say N.
427
Josh Triplett9def39be2013-10-30 08:09:45 -0700428config X86_FEATURE_NAMES
429 bool "Processor feature human-readable names" if EMBEDDED
430 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900431 help
Josh Triplett9def39be2013-10-30 08:09:45 -0700432 This option compiles in a table of x86 feature bits and corresponding
433 names. This is required to support /proc/cpuinfo and a few kernel
434 messages. You can disable this to save space, at the expense of
435 making those few kernel messages show numeric feature bits instead.
436
437 If in doubt, say Y.
438
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800439config X86_X2APIC
440 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200441 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900442 help
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800443 This enables x2apic support on CPUs that have this feature.
444
445 This allows 32-bit apic IDs (so it can support very large systems),
446 and accesses the local apic via MSRs not via mmio.
447
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800448 If you don't know what to do here, say N.
449
Yinghai Lu6695c852008-06-19 12:13:09 -0700450config X86_MPPARSE
Andy Shevchenko4590d982021-02-11 15:40:02 +0200451 bool "Enable MPS table" if ACPI
Jan Beulich7a527682008-10-30 10:38:24 +0000452 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200453 depends on X86_LOCAL_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900454 help
Yinghai Lu6695c852008-06-19 12:13:09 -0700455 For old smp systems that do not have proper acpi support. Newer systems
456 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700457
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000458config GOLDFISH
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +0100459 def_bool y
460 depends on X86_GOLDFISH
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000461
David Woodhouse76b04382018-01-11 21:46:25 +0000462config RETPOLINE
463 bool "Avoid speculative indirect branches in kernel"
464 default y
465 help
466 Compile kernel with the retpoline compiler options to guard against
467 kernel-to-user data leaks by avoiding speculative indirect
468 branches. Requires a compiler with -mindirect-branch=thunk-extern
469 support for full protection. The kernel may run slower.
470
Johannes Weinere6d42932019-01-29 17:44:36 -0500471config X86_CPU_RESCTRL
472 bool "x86 CPU resource control support"
Babu Moger6fe07ce2018-11-21 20:28:39 +0000473 depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100474 select KERNFS
Chen Yue79f15a2020-01-15 17:28:51 +0800475 select PROC_CPU_RESCTRL if PROC_FS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700476 help
Johannes Weinere6d42932019-01-29 17:44:36 -0500477 Enable x86 CPU resource control support.
Babu Moger6fe07ce2018-11-21 20:28:39 +0000478
479 Provide support for the allocation and monitoring of system resources
480 usage by the CPU.
481
482 Intel calls this Intel Resource Director Technology
483 (Intel(R) RDT). More information about RDT can be found in the
484 Intel x86 Architecture Software Developer Manual.
485
486 AMD calls this AMD Platform Quality of Service (AMD QoS).
487 More information about AMD QoS can be found in the AMD64 Technology
488 Platform Quality of Service Extensions manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700489
490 Say N if unsure.
491
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800492if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800493config X86_BIGSMP
494 bool "Support for big SMP systems with more than 8 CPUs"
495 depends on SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900496 help
Randy Dunlape133f6e2019-12-03 16:06:47 -0800497 This option is needed for the systems that have more than 8 CPUs.
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800498
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800499config X86_EXTENDED_PLATFORM
500 bool "Support for extended (non-PC) x86 platforms"
501 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900502 help
Ingo Molnar06ac8342009-01-27 18:11:43 +0100503 If you disable this option then the kernel will only support
504 standard PC platforms. (which covers the vast majority of
505 systems out there.)
506
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800507 If you enable this option then you'll be able to select support
508 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100509 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800510 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800511 RDC R-321x SoC
512 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200513 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200514 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100515
516 If you have one of these systems, or if you want to build a
517 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800518endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100519
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800520if X86_64
521config X86_EXTENDED_PLATFORM
522 bool "Support for extended (non-PC) x86 platforms"
523 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900524 help
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800525 If you disable this option then the kernel will only support
526 standard PC platforms. (which covers the vast majority of
527 systems out there.)
528
529 If you enable this option then you'll be able to select support
530 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800531 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800532 ScaleMP vSMP
533 SGI Ultraviolet
534
535 If you have one of these systems, or if you want to build a
536 generic distribution kernel, say Y here - otherwise say N.
537endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800538# This is an alphabetically sorted list of 64 bit extended platforms
539# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800540config X86_NUMACHIP
541 bool "Numascale NumaChip"
542 depends on X86_64
543 depends on X86_EXTENDED_PLATFORM
544 depends on NUMA
545 depends on SMP
546 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700547 depends on PCI_MMCONFIG
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900548 help
Steffen Persvold44b111b52011-12-06 00:07:26 +0800549 Adds support for Numascale NumaChip large-SMP systems. Needed to
550 enable more than ~168 cores.
551 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100552
Ingo Molnar6a485652009-01-27 18:29:13 +0100553config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800554 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100555 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100556 select PARAVIRT
557 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800558 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300559 depends on SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900560 help
Ingo Molnar6a485652009-01-27 18:29:13 +0100561 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
562 supposed to run on these EM64T-based machines. Only choose this option
563 if you have one of these machines.
564
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800565config X86_UV
566 bool "SGI Ultraviolet"
567 depends on X86_64
568 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500569 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800570 depends on EFI
Ingo Molnarc2209ea2021-04-20 09:47:42 +0200571 depends on KEXEC_CORE
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700572 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200573 depends on PCI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900574 help
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800575 This option is needed in order to support SGI Ultraviolet systems.
576 If you don't have one of these, you should say N here.
577
578# Following is an alphabetically sorted list of 32 bit extended platforms
579# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100580
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000581config X86_GOLDFISH
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +0100582 bool "Goldfish (Virtual Platform)"
583 depends on X86_EXTENDED_PLATFORM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900584 help
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000585 Enable support for the Goldfish virtual platform used primarily
586 for Android development. Unless you are building for the Android
587 Goldfish emulator say N here.
588
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800589config X86_INTEL_CE
590 bool "CE4100 TV platform"
591 depends on PCI
592 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800593 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800594 depends on X86_32
595 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800596 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100597 select OF
598 select OF_EARLY_FLATTREE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900599 help
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800600 Select for the Intel CE media processor (CE4100) SOC.
601 This option compiles in support for the CE4100 SOC for settop
602 boxes and media devices.
603
David Cohen4cb9b002013-12-16 17:37:26 -0800604config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100605 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100606 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800607 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000608 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200609 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000610 depends on X86_IO_APIC
David Cohen4cb9b002013-12-16 17:37:26 -0800611 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000612 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000613 select APB_TIMER
Mika Westerberg54b34aa2020-04-16 11:15:33 +0300614 select INTEL_SCU_PCI
Mika Westerberg15a713d2012-01-26 17:35:05 +0000615 select MFD_INTEL_MSIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900616 help
David Cohen4cb9b002013-12-16 17:37:26 -0800617 Select to build a kernel capable of supporting Intel MID (Mobile
618 Internet Device) platform systems which do not have the PCI legacy
619 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000620
David Cohen4cb9b002013-12-16 17:37:26 -0800621 Intel MID platforms are based on an Intel processor and chipset which
622 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100623
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000624config X86_INTEL_QUARK
625 bool "Intel Quark platform support"
626 depends on X86_32
627 depends on X86_EXTENDED_PLATFORM
628 depends on X86_PLATFORM_DEVICES
629 depends on X86_TSC
630 depends on PCI
631 depends on PCI_GOANY
632 depends on X86_IO_APIC
633 select IOSF_MBI
634 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200635 select COMMON_CLK
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900636 help
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000637 Select to include support for Quark X1000 SoC.
638 Say Y here if you have a Quark based system such as the Arduino
639 compatible Intel Galileo.
640
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000641config X86_INTEL_LPSS
642 bool "Intel Low Power Subsystem Support"
Sinan Kaya5962dd22019-01-02 18:10:37 +0000643 depends on X86 && ACPI && PCI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000644 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300645 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100646 select IOSF_MBI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900647 help
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000648 Select to build support for Intel Low Power Subsystem such as
649 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300650 things like clock tree (common clock framework) and pincontrol
651 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000652
Ken Xue92082a82015-02-06 08:27:51 +0800653config X86_AMD_PLATFORM_DEVICE
654 bool "AMD ACPI2Platform devices support"
655 depends on ACPI
656 select COMMON_CLK
657 select PINCTRL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900658 help
Ken Xue92082a82015-02-06 08:27:51 +0800659 Select to interpret AMD specific ACPI device to platform device
660 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
661 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
662 implemented under PINCTRL subsystem.
663
David E. Boxced3ce72014-09-17 22:13:50 -0700664config IOSF_MBI
665 tristate "Intel SoC IOSF Sideband support for SoC platforms"
666 depends on PCI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900667 help
David E. Boxced3ce72014-09-17 22:13:50 -0700668 This option enables sideband register access support for Intel SoC
669 platforms. On these platforms the IOSF sideband is used in lieu of
670 MSR's for some register accesses, mostly but not limited to thermal
671 and power. Drivers may query the availability of this device to
672 determine if they need the sideband in order to work on these
673 platforms. The sideband is available on the following SoC products.
674 This list is not meant to be exclusive.
675 - BayTrail
676 - Braswell
677 - Quark
678
679 You should say Y if you are running a kernel on one of these SoC's.
680
David E. Boxed2226b2014-09-17 22:13:51 -0700681config IOSF_MBI_DEBUG
682 bool "Enable IOSF sideband access through debugfs"
683 depends on IOSF_MBI && DEBUG_FS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900684 help
David E. Boxed2226b2014-09-17 22:13:51 -0700685 Select this option to expose the IOSF sideband access registers (MCR,
686 MDR, MCRX) through debugfs to write and read register information from
687 different units on the SoC. This is most useful for obtaining device
688 state information for debug and analysis. As this is a general access
689 mechanism, users of this option would have specific knowledge of the
690 device they want to access.
691
692 If you don't require the option or are in doubt, say N.
693
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800694config X86_RDC321X
695 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100696 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800697 depends on X86_EXTENDED_PLATFORM
698 select M486
699 select X86_REBOOTFIXUPS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900700 help
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800701 This option is needed for RDC R-321x system-on-chip, also known
702 as R-8610-(G).
703 If you don't have one of these chips, you should say N here.
704
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100705config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100706 bool "Support non-standard 32-bit SMP architectures"
707 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800708 depends on X86_EXTENDED_PLATFORM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900709 help
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800710 This option compiles in the bigsmp and STA2X11 default
711 subarchitectures. It is intended for a generic binary
712 kernel. If you select them all, kernel will probe it one by
713 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700714
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800715# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700716
Linus Torvaldsd949f362009-09-26 09:35:07 -0700717config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100718 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700719 # MCE code calls memory_failure():
720 depends on X86_MCE
721 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700722 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
723 depends on X86_64 || !SPARSEMEM
724 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700725
Alessandro Rubini83125a32012-04-04 19:40:21 +0200726config STA2X11
727 bool "STA2X11 Companion Chip Support"
728 depends on X86_32_NON_STANDARD && PCI
Alessandro Rubini83125a32012-04-04 19:40:21 +0200729 select SWIOTLB
730 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200731 select GPIOLIB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900732 help
Alessandro Rubini83125a32012-04-04 19:40:21 +0200733 This adds support for boards based on the STA2X11 IO-Hub,
734 a.k.a. "ConneXt". The chip is used in place of the standard
735 PC chipset, so all "standard" peripherals are missing. If this
736 option is selected the kernel will still be able to boot on
737 standard PC machines.
738
Shérab82148d12010-09-25 06:06:57 +0200739config X86_32_IRIS
740 tristate "Eurobraille/Iris poweroff module"
741 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900742 help
Shérab82148d12010-09-25 06:06:57 +0200743 The Iris machines from EuroBraille do not have APM or ACPI support
744 to shut themselves down properly. A special I/O sequence is
745 needed to do so, which is what this module does at
746 kernel shutdown.
747
748 This is only for Iris machines from EuroBraille.
749
750 If unused, say N.
751
Ingo Molnarae1e9132008-11-11 09:05:16 +0100752config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100753 def_bool y
754 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800755 depends on X86
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900756 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100757 Calculate simpler /proc/<PID>/wchan values. If this option
758 is disabled then wchan values will recurse back to the
759 caller function. This provides more accurate wchan values,
760 at the expense of slightly more scheduling overhead.
761
762 If in doubt, say "Y".
763
Borislav Petkov6276a072013-03-04 21:20:21 +0100764menuconfig HYPERVISOR_GUEST
765 bool "Linux guest support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900766 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100767 Say Y here to enable options for running Linux under various hyper-
768 visors. This option enables basic hypervisor detection and platform
769 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100770
Borislav Petkov6276a072013-03-04 21:20:21 +0100771 If you say N, all options in this submenu will be skipped and
772 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100773
Borislav Petkov6276a072013-03-04 21:20:21 +0100774if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100775
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100776config PARAVIRT
777 bool "Enable paravirtualization code"
Juergen Grossa0e2bf72021-03-11 15:23:09 +0100778 depends on HAVE_STATIC_CALL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900779 help
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100780 This changes the kernel so it can modify itself when it is run
781 under a hypervisor, potentially improving performance significantly
782 over full virtualization. However, when run without a hypervisor
783 the kernel is theoretically slower and slightly larger.
784
Juergen Grossc00a2802018-08-28 09:40:21 +0200785config PARAVIRT_XXL
786 bool
787
Borislav Petkov6276a072013-03-04 21:20:21 +0100788config PARAVIRT_DEBUG
789 bool "paravirt-ops debugging"
790 depends on PARAVIRT && DEBUG_KERNEL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900791 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100792 Enable to debug paravirt_ops internals. Specifically, BUG if
793 a paravirt_op is missing when it is called.
794
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700795config PARAVIRT_SPINLOCKS
796 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700797 depends on PARAVIRT && SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900798 help
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700799 Paravirtualized spinlocks allow a pvops backend to replace the
800 spinlock implementation with something virtualization-friendly
801 (for example, block the virtual CPU rather than spinning).
802
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530803 It has a minimal impact on native kernels and gives a nice performance
804 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700805
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530806 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700807
Zhao Yakuiecca25022019-04-30 11:45:23 +0800808config X86_HV_CALLBACK_VECTOR
809 def_bool n
810
Borislav Petkov6276a072013-03-04 21:20:21 +0100811source "arch/x86/xen/Kconfig"
812
813config KVM_GUEST
814 bool "KVM Guest support (including kvmclock)"
815 depends on PARAVIRT
816 select PARAVIRT_CLOCK
Marcelo Tosattia1c44232019-07-03 20:51:29 -0300817 select ARCH_CPUIDLE_HALTPOLL
Vitaly Kuznetsovb1d40572020-05-25 16:41:23 +0200818 select X86_HV_CALLBACK_VECTOR
Borislav Petkov6276a072013-03-04 21:20:21 +0100819 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900820 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100821 This option enables various optimizations for running under the KVM
822 hypervisor. It includes a paravirtualized clock, so that instead
823 of relying on a PIT (or probably other) emulation by the
824 underlying device model, the host provides the guest with
825 timing infrastructure such as time of day, and system time
826
Marcelo Tosattia1c44232019-07-03 20:51:29 -0300827config ARCH_CPUIDLE_HALTPOLL
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +0100828 def_bool n
829 prompt "Disable host haltpoll when loading haltpoll driver"
830 help
Marcelo Tosattia1c44232019-07-03 20:51:29 -0300831 If virtualized under KVM, disable host haltpoll.
832
Maran Wilson77336072018-12-10 11:07:28 -0800833config PVH
834 bool "Support for running PVH guests"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900835 help
Maran Wilson77336072018-12-10 11:07:28 -0800836 This option enables the PVH entry point for guest virtual machines
837 as specified in the x86/HVM direct boot ABI.
838
Borislav Petkov6276a072013-03-04 21:20:21 +0100839config PARAVIRT_TIME_ACCOUNTING
840 bool "Paravirtual steal time accounting"
841 depends on PARAVIRT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900842 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100843 Select this option to enable fine granularity task steal time
844 accounting. Time spent executing other tasks in parallel with
845 the current vCPU is discounted from the vCPU power. To account for
846 that, there can be a small performance impact.
847
848 If in doubt, say N here.
849
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200850config PARAVIRT_CLOCK
851 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200852
Jan Kiszka4a362602017-11-27 09:11:46 +0100853config JAILHOUSE_GUEST
854 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100855 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100856 select X86_PM_TIMER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900857 help
Jan Kiszka4a362602017-11-27 09:11:46 +0100858 This option allows to run Linux as guest in a Jailhouse non-root
859 cell. You can leave this option disabled if you only want to start
860 Jailhouse and run Linux afterwards in the root cell.
861
Zhao Yakuiec7972c2019-04-30 11:45:24 +0800862config ACRN_GUEST
863 bool "ACRN Guest support"
864 depends on X86_64
Zhao Yakui498ad392019-04-30 11:45:25 +0800865 select X86_HV_CALLBACK_VECTOR
Zhao Yakuiec7972c2019-04-30 11:45:24 +0800866 help
867 This option allows to run Linux as guest in the ACRN hypervisor. ACRN is
868 a flexible, lightweight reference open-source hypervisor, built with
869 real-time and safety-criticality in mind. It is built for embedded
870 IOT with small footprint and real-time features. More details can be
871 found in https://projectacrn.org/.
872
Borislav Petkov6276a072013-03-04 21:20:21 +0100873endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400874
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100875source "arch/x86/Kconfig.cpu"
876
877config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100878 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100879 prompt "HPET Timer Support" if X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900880 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100881 Use the IA-PC HPET (High Precision Event Timer) to manage
882 time in preference to the PIT and RTC, if a HPET is
883 present.
884 HPET is the next generation timer replacing legacy 8254s.
885 The HPET provides a stable time base on SMP
886 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200887 as it is off-chip. The interface used is documented
888 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100889
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100890 You can safely choose Y here. However, HPET will only be
891 activated if the platform and the BIOS support this feature.
892 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100893
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100894 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100895
896config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100897 def_bool y
Anand K Mistry3228e1d2021-02-04 18:32:32 +1100898 depends on HPET_TIMER && (RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100899
David Rientjes6a108a12011-01-20 14:44:16 -0800900# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100901# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700902config DMI
903 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800904 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800905 bool "Enable DMI scanning" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900906 help
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700907 Enabled scanning of DMI to identify machine quirks. Say Y
908 here unless you have verified that your setup is not
909 affected by entries in the DMI blacklist. Required by PNP
910 BIOS code.
911
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100912config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700913 bool "Old AMD GART IOMMU support"
Christoph Hellwig2f9237d2020-07-08 09:30:00 +0200914 select DMA_OPS
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200915 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100916 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200917 depends on X86_64 && PCI && AMD_NB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900918 help
Ingo Molnarced3c422013-10-06 11:45:20 +0200919 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
920 GART based hardware IOMMUs.
921
922 The GART supports full DMA access for devices with 32-bit access
923 limitations, on systems with more than 3 GB. This is usually needed
924 for USB, sound, many IDE/SATA chipsets and some other devices.
925
926 Newer systems typically have a modern AMD IOMMU, supported via
927 the CONFIG_AMD_IOMMU=y config option.
928
929 In normal configurations this driver is only active when needed:
930 there's more than 3 GB of memory and the system contains a
931 32-bit limited device.
932
933 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100934
Mike Travis1184dc22008-05-12 21:21:12 +0200935config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200936 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700937 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800938 select CPUMASK_OFFSTACK
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900939 help
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200940 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200941 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100942
Ingo Molnaraec64872018-02-10 12:36:29 +0100943#
944# The maximum number of CPUs supported:
945#
946# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
947# and which can be configured interactively in the
948# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
949#
950# The ranges are different on 32-bit and 64-bit kernels, depending on
951# hardware capabilities and scalability features of the kernel.
952#
953# ( If MAXSMP is enabled we just use the highest possible value and disable
954# interactive configuration. )
955#
956
957config NR_CPUS_RANGE_BEGIN
958 int
959 default NR_CPUS_RANGE_END if MAXSMP
960 default 1 if !SMP
961 default 2
962
963config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800964 int
965 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100966 default 64 if SMP && X86_BIGSMP
967 default 8 if SMP && !X86_BIGSMP
968 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800969
Ingo Molnaraec64872018-02-10 12:36:29 +0100970config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800971 int
972 depends on X86_64
Scott Wood1edae1a2019-10-12 02:00:54 -0500973 default 8192 if SMP && CPUMASK_OFFSTACK
974 default 512 if SMP && !CPUMASK_OFFSTACK
Ingo Molnaraec64872018-02-10 12:36:29 +0100975 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800976
Ingo Molnaraec64872018-02-10 12:36:29 +0100977config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800978 int
979 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100980 default 32 if X86_BIGSMP
981 default 8 if SMP
982 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800983
Ingo Molnaraec64872018-02-10 12:36:29 +0100984config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800985 int
986 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100987 default 8192 if MAXSMP
988 default 64 if SMP
989 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800990
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100991config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800992 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +0100993 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
994 default NR_CPUS_DEFAULT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900995 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100996 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500997 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +0300998 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100999 minimum value which makes sense is 2.
1000
Ingo Molnaraec64872018-02-10 12:36:29 +01001001 This is purely to save memory: each supported CPU adds about 8KB
1002 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001003
Tim Chen66558b72021-09-24 20:51:04 +12001004config SCHED_CLUSTER
1005 bool "Cluster scheduler support"
1006 depends on SMP
1007 default y
1008 help
1009 Cluster scheduler support improves the CPU scheduler's decision
1010 making when dealing with machines that have clusters of CPUs.
1011 Cluster usually means a couple of CPUs which are placed closely
1012 by sharing mid-level caches, last-level cache tags or internal
1013 busses.
1014
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001015config SCHED_SMT
Thomas Gleixnerdbe73362018-11-25 19:33:37 +01001016 def_bool y if SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001017
1018config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001019 def_bool y
1020 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001021 depends on SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001022 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001023 Multi-core scheduler support improves the CPU scheduler's decision
1024 making when dealing with multi-core CPU chips at a cost of slightly
1025 increased overhead in some places. If unsure say N here.
1026
Tim Chende966cf2016-11-29 10:43:27 -08001027config SCHED_MC_PRIO
1028 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001029 depends on SCHED_MC && CPU_SUP_INTEL
1030 select X86_INTEL_PSTATE
1031 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001032 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001033 help
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001034 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1035 core ordering determined at manufacturing time, which allows
1036 certain cores to reach higher turbo frequencies (when running
1037 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001038
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001039 Enabling this kernel feature teaches the scheduler about
1040 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1041 scheduler's CPU selection logic accordingly, so that higher
1042 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001043
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001044 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001045
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001046 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001047
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001048config UP_LATE_INIT
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001049 def_bool y
1050 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001051
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001052config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001053 bool "Local APIC support on uniprocessors" if !PCI_MSI
1054 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001055 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001056 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001057 A local APIC (Advanced Programmable Interrupt Controller) is an
1058 integrated interrupt controller in the CPU. If you have a single-CPU
1059 system which has a processor with a local APIC, you can say Y here to
1060 enable and use it. If you say Y here even though your machine doesn't
1061 have a local APIC, then the kernel will still run with no slowdown at
1062 all. The local APIC supports CPU-generated self-interrupts (timer,
1063 performance counters), and the NMI watchdog which detects hard
1064 lockups.
1065
1066config X86_UP_IOAPIC
1067 bool "IO-APIC support on uniprocessors"
1068 depends on X86_UP_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001069 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001070 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1071 SMP-capable replacement for PC-style interrupt controllers. Most
1072 SMP systems and many recent uniprocessor systems have one.
1073
1074 If you have a single-CPU system with an IO-APIC, you can say Y here
1075 to use it. If you say Y here even though your machine doesn't have
1076 an IO-APIC, then the kernel will still run with no slowdown at all.
1077
1078config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001079 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001080 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001081 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001082 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001083
1084config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001085 def_bool y
1086 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001087
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001088config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1089 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001090 depends on X86_IO_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001091 help
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001092 This option enables a workaround that fixes a source of
1093 spurious interrupts. This is recommended when threaded
1094 interrupt handling is used on systems where the generation of
1095 superfluous "boot interrupts" cannot be disabled.
1096
1097 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1098 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1099 kernel does during interrupt handling). On chipsets where this
1100 boot IRQ generation cannot be disabled, this workaround keeps
1101 the original IRQ line masked so that only the equivalent "boot
1102 IRQ" is delivered to the CPUs. The workaround also tells the
1103 kernel to set up the IRQ handler on the boot IRQ line. In this
1104 way only one interrupt is delivered to the kernel. Otherwise
1105 the spurious second interrupt may cause the kernel to bring
1106 down (vital) interrupt lines.
1107
1108 Only affects "broken" chipsets. Interrupt sharing may be
1109 increased on these systems.
1110
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001111config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001112 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001113 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001114 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001115 help
Andi Kleenbab9bc62009-07-09 00:31:38 +02001116 Machine Check support allows the processor to notify the
1117 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001118 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001119 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001120
Tony Luck5de97c92017-03-27 11:33:03 +02001121config X86_MCELOG_LEGACY
1122 bool "Support for deprecated /dev/mcelog character device"
1123 depends on X86_MCE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001124 help
Tony Luck5de97c92017-03-27 11:33:03 +02001125 Enable support for /dev/mcelog which is needed by the old mcelog
1126 userspace logging daemon. Consider switching to the new generation
1127 rasdaemon solution.
1128
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001129config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001130 def_bool y
1131 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001132 depends on X86_MCE && X86_LOCAL_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001133 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001134 Additional support for intel specific MCE features such as
1135 the thermal monitor.
1136
1137config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001138 def_bool y
1139 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001140 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001141 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001142 Additional support for AMD specific MCE features such as
1143 the DRAM Error Threshold.
1144
Andi Kleen4efc0672009-04-28 19:07:31 +02001145config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001146 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001147 depends on X86_32 && X86_MCE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001148 help
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001149 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001150 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001151 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001152
Andi Kleenb2762682009-02-12 13:49:31 +01001153config X86_MCE_THRESHOLD
1154 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001155 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001156
Andi Kleenea149b32009-04-29 19:31:00 +02001157config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001158 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001159 tristate "Machine check injector support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001160 help
Andi Kleenea149b32009-04-29 19:31:00 +02001161 Provide support for injecting machine checks for testing purposes.
1162 If you don't know what a machine check is and you don't do kernel
1163 QA it is safe to say n.
1164
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001165source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001166
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001167config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001168 bool "Legacy VM86 support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001169 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001170 help
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001171 This option allows user programs to put the CPU into V8086
1172 mode, which is an 80286-era approximation of 16-bit real mode.
1173
1174 Some very old versions of X and/or vbetool require this option
1175 for user mode setting. Similarly, DOSEMU will use it if
1176 available to accelerate real mode DOS programs. However, any
1177 recent version of DOSEMU, X, or vbetool should be fully
1178 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001179 fall back to software emulation. Nevertheless, if you are using
1180 a 16-bit DOS program where 16-bit performance matters, vm86
1181 mode might be faster than emulation and you might want to
1182 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001183
Ingo Molnar1e642812015-09-05 08:58:10 +02001184 Note that any app that works on a 64-bit kernel is unlikely to
1185 need this option, as 64-bit kernels don't, and can't, support
1186 V8086 mode. This option is also unrelated to 16-bit protected
1187 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001188
Ingo Molnar1e642812015-09-05 08:58:10 +02001189 Enabling this option increases the complexity of the kernel
1190 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001191
Ingo Molnar1e642812015-09-05 08:58:10 +02001192 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001193
1194config VM86
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001195 bool
1196 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001197
1198config X86_16BIT
1199 bool "Enable support for 16-bit segments" if EXPERT
1200 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001201 depends on MODIFY_LDT_SYSCALL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001202 help
H. Peter Anvin34273f42014-05-04 10:36:22 -07001203 This option is required by programs like Wine to run 16-bit
1204 protected mode legacy code on x86 processors. Disabling
1205 this option saves about 300 bytes on i386, or around 6K text
1206 plus 16K runtime memory on x86-64,
1207
1208config X86_ESPFIX32
1209 def_bool y
1210 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001211
H. Peter Anvin197725d2014-05-04 10:00:49 -07001212config X86_ESPFIX64
1213 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001214 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001215
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001216config X86_VSYSCALL_EMULATION
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001217 bool "Enable vsyscall emulation" if EXPERT
1218 default y
1219 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001220 help
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001221 This enables emulation of the legacy vsyscall page. Disabling
1222 it is roughly equivalent to booting with vsyscall=none, except
1223 that it will also disable the helpful warning if a program
1224 tries to use a vsyscall. With this option set to N, offending
1225 programs will just segfault, citing addresses of the form
1226 0xffffffffff600?00.
1227
1228 This option is required by many programs built before 2013, and
1229 care should be used even with newer programs if set to N.
1230
1231 Disabling this option saves about 7K of kernel size and
1232 possibly 4K of additional runtime pagetable memory.
1233
Thomas Gleixner111e7b12019-11-12 21:40:33 +01001234config X86_IOPL_IOPERM
1235 bool "IOPERM and IOPL Emulation"
Thomas Gleixnera24ca992019-11-11 23:03:29 +01001236 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001237 help
Thomas Gleixner111e7b12019-11-12 21:40:33 +01001238 This enables the ioperm() and iopl() syscalls which are necessary
1239 for legacy applications.
1240
Thomas Gleixnerc8137ac2019-11-11 23:03:28 +01001241 Legacy IOPL support is an overbroad mechanism which allows user
1242 space aside of accessing all 65536 I/O ports also to disable
1243 interrupts. To gain this access the caller needs CAP_SYS_RAWIO
1244 capabilities and permission from potentially active security
1245 modules.
1246
1247 The emulation restricts the functionality of the syscall to
1248 only allowing the full range I/O port access, but prevents the
Thomas Gleixnera24ca992019-11-11 23:03:29 +01001249 ability to disable interrupts from user space which would be
1250 granted if the hardware IOPL mechanism would be used.
Thomas Gleixnerc8137ac2019-11-11 23:03:28 +01001251
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001252config TOSHIBA
1253 tristate "Toshiba Laptop support"
1254 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001255 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001256 This adds a driver to safely access the System Management Mode of
1257 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1258 not work on models with a Phoenix BIOS. The System Management Mode
1259 is used to set the BIOS and power saving options on Toshiba portables.
1260
1261 For information on utilities to make use of this driver see the
1262 Toshiba Linux utilities web site at:
1263 <http://www.buzzard.org.uk/toshiba/>.
1264
1265 Say Y if you intend to run this kernel on a Toshiba portable.
1266 Say N otherwise.
1267
1268config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001269 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001270 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001271 select SENSORS_DELL_SMM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001272 help
Pali Rohár039ae582015-05-14 13:16:37 +02001273 This option enables legacy /proc/i8k userspace interface in hwmon
1274 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1275 temperature and allows controlling fan speeds of Dell laptops via
1276 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1277 it reports also power and hotkey status. For fan speed control is
1278 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001279
Pali Rohár039ae582015-05-14 13:16:37 +02001280 Say Y if you intend to run this kernel on old Dell laptops or want to
1281 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001282 Say N otherwise.
1283
1284config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001285 bool "Enable X86 board specific fixups for reboot"
1286 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001287 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001288 This enables chipset and/or board specific fixups to be done
1289 in order to get reboot to work correctly. This is only needed on
1290 some combinations of hardware and BIOS. The symptom, for which
1291 this config is intended, is when reboot ends with a stalled/hung
1292 system.
1293
1294 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001295 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001296
1297 Say Y if you want to enable the fixup. Currently, it's safe to
1298 enable this option even if you don't need it.
1299 Say N otherwise.
1300
1301config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001302 bool "CPU microcode loading support"
1303 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001304 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001305 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001306 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001307 Intel and AMD processors. The Intel support is for the IA32 family,
1308 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1309 AMD support is for families 0x10 and later. You will obviously need
1310 the actual microcode binary data itself which is not shipped with
1311 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001312
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001313 The preferred method to load microcode from a detached initrd is described
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001314 in Documentation/x86/microcode.rst. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001315 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1316 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001317
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001318 In addition, you can build the microcode into the kernel. For that you
1319 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1320 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001321
Peter Oruba8d86f392008-07-28 18:44:21 +02001322config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001323 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001324 depends on MICROCODE
1325 default MICROCODE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001326 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001327 This options enables microcode patch loading support for Intel
1328 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001329
Alanb8989db2014-01-20 18:01:56 +00001330 For the current Intel microcode data package go to
1331 <https://downloadcenter.intel.com> and search for
1332 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001333
Peter Oruba80cc9f12008-07-28 18:44:22 +02001334config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001335 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001336 depends on MICROCODE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001337 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001338 If you select this option, microcode patch loading support for AMD
1339 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001340
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001341config MICROCODE_OLD_INTERFACE
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001342 bool "Ancient loading interface (DEPRECATED)"
1343 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001344 depends on MICROCODE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001345 help
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001346 DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface
1347 which was used by userspace tools like iucode_tool and microcode.ctl.
1348 It is inadequate because it runs too late to be able to properly
1349 load microcode on a machine and it needs special tools. Instead, you
1350 should've switched to the early loading method with the initrd or
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001351 builtin microcode by now: Documentation/x86/microcode.rst
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001352
1353config X86_MSR
1354 tristate "/dev/cpu/*/msr - Model-specific register support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001355 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001356 This device gives privileged processes access to the x86
1357 Model-Specific Registers (MSRs). It is a character device with
1358 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1359 MSR accesses are directed to a specific CPU on multi-processor
1360 systems.
1361
1362config X86_CPUID
1363 tristate "/dev/cpu/*/cpuid - CPU information support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001364 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001365 This device gives processes access to the x86 CPUID instruction to
1366 be executed on a specific processor. It is a character device
1367 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1368 /dev/cpu/31/cpuid.
1369
1370choice
1371 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001372 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001373 depends on X86_32
1374
1375config NOHIGHMEM
1376 bool "off"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001377 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001378 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1379 However, the address space of 32-bit x86 processors is only 4
1380 Gigabytes large. That means that, if you have a large amount of
1381 physical memory, not all of it can be "permanently mapped" by the
1382 kernel. The physical memory that's not permanently mapped is called
1383 "high memory".
1384
1385 If you are compiling a kernel which will never run on a machine with
1386 more than 1 Gigabyte total physical RAM, answer "off" here (default
1387 choice and suitable for most users). This will result in a "3GB/1GB"
1388 split: 3GB are mapped so that each process sees a 3GB virtual memory
1389 space and the remaining part of the 4GB virtual memory space is used
1390 by the kernel to permanently map as much physical memory as
1391 possible.
1392
1393 If the machine has between 1 and 4 Gigabytes physical RAM, then
1394 answer "4GB" here.
1395
1396 If more than 4 Gigabytes is used then answer "64GB" here. This
1397 selection turns Intel PAE (Physical Address Extension) mode on.
1398 PAE implements 3-level paging on IA32 processors. PAE is fully
1399 supported by Linux, PAE mode is implemented on all recent Intel
1400 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1401 then the kernel will not boot on CPUs that don't support PAE!
1402
1403 The actual amount of total physical memory will either be
1404 auto detected or can be forced by using a kernel command line option
1405 such as "mem=256M". (Try "man bootparam" or see the documentation of
1406 your boot loader (lilo or loadlin) about how to pass options to the
1407 kernel at boot time.)
1408
1409 If unsure, say "off".
1410
1411config HIGHMEM4G
1412 bool "4GB"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001413 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001414 Select this if you have a 32-bit processor and between 1 and 4
1415 gigabytes of physical RAM.
1416
1417config HIGHMEM64G
1418 bool "64GB"
Maciej W. Rozycki0ef34392021-04-14 12:38:28 +02001419 depends on !M486SX && !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001420 select X86_PAE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001421 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001422 Select this if you have a 32-bit processor and more than 4
1423 gigabytes of physical RAM.
1424
1425endchoice
1426
1427choice
David Rientjes6a108a12011-01-20 14:44:16 -08001428 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001429 default VMSPLIT_3G
1430 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001431 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001432 Select the desired split between kernel and user memory.
1433
1434 If the address range available to the kernel is less than the
1435 physical memory installed, the remaining memory will be available
1436 as "high memory". Accessing high memory is a little more costly
1437 than low memory, as it needs to be mapped into the kernel first.
1438 Note that increasing the kernel address space limits the range
1439 available to user programs, making the address space there
1440 tighter. Selecting anything other than the default 3G/1G split
1441 will also likely make your kernel incompatible with binary-only
1442 kernel modules.
1443
1444 If you are not absolutely sure what you are doing, leave this
1445 option alone!
1446
1447 config VMSPLIT_3G
1448 bool "3G/1G user/kernel split"
1449 config VMSPLIT_3G_OPT
1450 depends on !X86_PAE
1451 bool "3G/1G user/kernel split (for full 1G low memory)"
1452 config VMSPLIT_2G
1453 bool "2G/2G user/kernel split"
1454 config VMSPLIT_2G_OPT
1455 depends on !X86_PAE
1456 bool "2G/2G user/kernel split (for full 2G low memory)"
1457 config VMSPLIT_1G
1458 bool "1G/3G user/kernel split"
1459endchoice
1460
1461config PAGE_OFFSET
1462 hex
1463 default 0xB0000000 if VMSPLIT_3G_OPT
1464 default 0x80000000 if VMSPLIT_2G
1465 default 0x78000000 if VMSPLIT_2G_OPT
1466 default 0x40000000 if VMSPLIT_1G
1467 default 0xC0000000
1468 depends on X86_32
1469
1470config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001471 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001472 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001473
1474config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001475 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001476 depends on X86_32 && !HIGHMEM4G
Christoph Hellwigd4a451d2018-04-03 16:24:20 +02001477 select PHYS_ADDR_T_64BIT
Christian Melki9d99c712015-10-05 17:31:33 +02001478 select SWIOTLB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001479 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001480 PAE is required for NX support, and furthermore enables
1481 larger swapspace support for non-overcommit purposes. It
1482 has the cost of more pagetable lookup overhead, and also
1483 consumes more pagetable space per process.
1484
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001485config X86_5LEVEL
1486 bool "Enable 5-level page tables support"
Kirill A. Shutemov18ec1ea2019-09-13 12:54:52 +03001487 default y
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001488 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001489 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001490 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001491 help
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001492 5-level paging enables access to larger address space:
1493 upto 128 PiB of virtual address space and 4 PiB of
1494 physical address space.
1495
1496 It will be supported by future Intel CPUs.
1497
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001498 A kernel with the option enabled can be booted on machines that
1499 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001500
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001501 See Documentation/x86/x86_64/5level-paging.rst for more
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001502 information.
1503
1504 Say N if unsure.
1505
Ingo Molnar10971ab2015-03-05 08:18:23 +01001506config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001507 def_bool y
Vlastimil Babka2e1da132019-08-07 15:02:58 +02001508 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001509 help
Ingo Molnar10971ab2015-03-05 08:18:23 +01001510 Certain kernel features effectively disable kernel
1511 linear 1 GB mappings (even if the CPU otherwise
1512 supports them), so don't confuse the user by printing
1513 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001514
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001515config X86_CPA_STATISTICS
1516 bool "Enable statistic for Change Page Attribute"
1517 depends on DEBUG_FS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001518 help
Ingo Molnarb75baaf2019-11-20 15:57:04 +01001519 Expose statistics about the Change Page Attribute mechanism, which
Colin Ian Kinga9432452019-04-16 11:57:51 +01001520 helps to determine the effectiveness of preserving large and huge
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001521 page mappings when mapping protections are changed.
1522
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001523config AMD_MEM_ENCRYPT
1524 bool "AMD Secure Memory Encryption (SME) support"
1525 depends on X86_64 && CPU_SUP_AMD
David Rientjes82fef0a2020-04-14 17:05:01 -07001526 select DMA_COHERENT_POOL
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +03001527 select DYNAMIC_PHYSICAL_MASK
Ard Biesheuvelce9084b2019-02-02 10:41:17 +01001528 select ARCH_USE_MEMREMAP_PROT
Tom Lendacky9087c372019-07-10 19:01:19 +00001529 select ARCH_HAS_FORCE_DMA_UNENCRYPTED
Joerg Roedel597cfe482020-09-07 15:15:24 +02001530 select INSTRUCTION_DECODER
Tom Lendacky22916412021-03-04 16:40:11 -06001531 select ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001532 help
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001533 Say yes to enable support for the encryption of system memory.
1534 This requires an AMD processor that supports Secure Memory
1535 Encryption (SME).
1536
1537config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1538 bool "Activate AMD Secure Memory Encryption (SME) by default"
1539 default y
1540 depends on AMD_MEM_ENCRYPT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001541 help
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001542 Say yes to have system memory encrypted by default if running on
1543 an AMD processor that supports Secure Memory Encryption (SME).
1544
1545 If set to Y, then the encryption of system memory can be
1546 deactivated with the mem_encrypt=off command line option.
1547
1548 If set to N, then the encryption of system memory can be
1549 activated with the mem_encrypt=on command line option.
1550
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001551# Common NUMA Features
1552config NUMA
Randy Dunlape133f6e2019-12-03 16:06:47 -08001553 bool "NUMA Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001554 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001555 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1556 default y if X86_BIGSMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001557 help
Randy Dunlape133f6e2019-12-03 16:06:47 -08001558 Enable NUMA (Non-Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001559
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001560 The kernel will try to allocate memory used by a CPU on the
1561 local memory controller of the CPU and add some more
1562 NUMA awareness to the kernel.
1563
Ingo Molnarc280ea52008-11-08 13:29:45 +01001564 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001565 (or later), AMD Opteron, or EM64T NUMA.
1566
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001567 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001568 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001569
1570 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001571
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001572config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001573 def_bool y
1574 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001575 depends on X86_64 && NUMA && PCI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001576 help
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001577 Enable AMD NUMA node topology detection. You should say Y here if
1578 you have a multi processor AMD system. This uses an old method to
1579 read the NUMA configuration directly from the builtin Northbridge
1580 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1581 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001582
1583config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001584 def_bool y
1585 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001586 depends on X86_64 && NUMA && ACPI && PCI
1587 select ACPI_NUMA
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001588 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001589 Enable ACPI SRAT based node topology detection.
1590
1591config NUMA_EMU
1592 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001593 depends on NUMA
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001594 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001595 Enable NUMA emulation. A flat machine will be split
1596 into virtual nodes when booted with "numa=fake=N", where N is the
1597 number of nodes. This is only useful for debugging.
1598
1599config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001600 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001601 range 1 10
1602 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001603 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001604 default "3"
Mike Rapoporta9ee6cf2021-06-28 19:43:01 -07001605 depends on NUMA
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001606 help
Mike Travis1184dc22008-05-12 21:21:12 +02001607 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001608 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001609
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001610config ARCH_FLATMEM_ENABLE
1611 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001612 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001613
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001614config ARCH_SPARSEMEM_ENABLE
1615 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001616 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001617 select SPARSEMEM_STATIC if X86_32
1618 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1619
Tejun Heo3b166512011-04-01 11:15:12 +02001620config ARCH_SPARSEMEM_DEFAULT
Mike Rapoport6ad57f72019-04-24 16:24:11 +03001621 def_bool X86_64 || (NUMA && X86_32)
Tejun Heo3b166512011-04-01 11:15:12 +02001622
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001623config ARCH_SELECT_MEMORY_MODEL
1624 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001625 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001626
1627config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001628 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001629 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001630 help
1631 This option enables a sysfs memory/probe interface for testing.
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001632 See Documentation/admin-guide/mm/memory-hotplug.rst for more information.
Toshi Kania0842b72013-07-19 11:47:48 -06001633 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001634
Tejun Heo3b166512011-04-01 11:15:12 +02001635config ARCH_PROC_KCORE_TEXT
1636 def_bool y
1637 depends on X86_64 && PROC_KCORE
1638
Avi Kivitya29815a2010-01-10 16:28:09 +02001639config ILLEGAL_POINTER_VALUE
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001640 hex
1641 default 0 if X86_32
1642 default 0xdead000000000000 if X86_64
Avi Kivitya29815a2010-01-10 16:28:09 +02001643
Dan Williams7a678322015-08-19 00:34:34 -04001644config X86_PMEM_LEGACY_DEVICE
1645 bool
1646
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001647config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001648 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001649 depends on PHYS_ADDR_T_64BIT
1650 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001651 select X86_PMEM_LEGACY_DEVICE
Dan Williams7b27a862020-02-16 12:01:16 -08001652 select NUMA_KEEP_MEMINFO if NUMA
Dan Williams9f53f9f2015-06-09 15:33:45 -04001653 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001654 help
1655 Treat memory marked using the non-standard e820 type of 12 as used
1656 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1657 The kernel will offer these regions to the 'pmem' driver so
1658 they can be used for persistent storage.
1659
1660 Say Y if unsure.
1661
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001662config HIGHPTE
1663 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001664 depends on HIGHMEM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001665 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001666 The VM uses one page table entry for each page of physical memory.
1667 For systems with a lot of RAM, this can be wasteful of precious
1668 low memory. Setting this option will put user-space page table
1669 entries in high memory.
1670
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001671config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001672 bool "Check for low memory corruption"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001673 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001674 Periodically check for memory corruption in low memory, which
1675 is suspected to be caused by BIOS. Even when enabled in the
1676 configuration, it is disabled at runtime. Enable it by
1677 setting "memory_corruption_check=1" on the kernel command
1678 line. By default it scans the low 64k of memory every 60
1679 seconds; see the memory_corruption_check_size and
1680 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001681 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001682
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001683 When enabled with the default parameters, this option has
1684 almost no overhead, as it reserves a relatively small amount
1685 of memory and scans it infrequently. It both detects corruption
1686 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001687
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001688 It is, however, intended as a diagnostic tool; if repeatable
1689 BIOS-originated corruption always affects the same memory,
1690 you can use memmap= to prevent the kernel from using that
1691 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001692
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001693config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001694 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001695 depends on X86_CHECK_BIOS_CORRUPTION
1696 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001697 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001698 Set whether the default state of memory_corruption_check is
1699 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001700
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001701config MATH_EMULATION
1702 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001703 depends on MODIFY_LDT_SYSCALL
Arnd Bergmann87d60212019-10-01 16:23:35 +02001704 prompt "Math emulation" if X86_32 && (M486SX || MELAN)
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001705 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001706 Linux can emulate a math coprocessor (used for floating point
1707 operations) if you don't have one. 486DX and Pentium processors have
1708 a math coprocessor built in, 486SX and 386 do not, unless you added
1709 a 487DX or 387, respectively. (The messages during boot time can
1710 give you some hints here ["man dmesg"].) Everyone needs either a
1711 coprocessor or this emulation.
1712
1713 If you don't have a math coprocessor, you need to say Y here; if you
1714 say Y here even though you have a coprocessor, the coprocessor will
1715 be used nevertheless. (This behavior can be changed with the kernel
1716 command line option "no387", which comes handy if your coprocessor
1717 is broken. Try "man bootparam" or see the documentation of your boot
1718 loader (lilo or loadlin) about how to pass options to the kernel at
1719 boot time.) This means that it is a good idea to say Y here if you
1720 intend to use this kernel on different machines.
1721
1722 More information about the internals of the Linux math coprocessor
1723 emulation can be found in <file:arch/x86/math-emu/README>.
1724
1725 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1726 kernel, it won't hurt.
1727
1728config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001729 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001730 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001731 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001732 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1733 the Memory Type Range Registers (MTRRs) may be used to control
1734 processor access to memory ranges. This is most useful if you have
1735 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1736 allows bus write transfers to be combined into a larger transfer
1737 before bursting over the PCI/AGP bus. This can increase performance
1738 of image write operations 2.5 times or more. Saying Y here creates a
1739 /proc/mtrr file which may be used to manipulate your processor's
1740 MTRRs. Typically the X server should use this.
1741
1742 This code has a reasonably generic interface so that similar
1743 control registers on other processors can be easily supported
1744 as well:
1745
1746 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1747 Registers (ARRs) which provide a similar functionality to MTRRs. For
1748 these, the ARRs are used to emulate the MTRRs.
1749 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1750 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1751 write-combining. All of these processors are supported by this code
1752 and it makes sense to say Y here if you have one of them.
1753
1754 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1755 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1756 can lead to all sorts of problems, so it's good to say Y here.
1757
1758 You can safely say Y even if your machine doesn't have MTRRs, you'll
1759 just add about 9 KB to your kernel.
1760
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001761 See <file:Documentation/x86/mtrr.rst> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001762
Yinghai Lu95ffa242008-04-29 03:52:33 -07001763config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001764 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001765 prompt "MTRR cleanup support"
1766 depends on MTRR
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001767 help
Thomas Gleixneraba37282008-07-15 14:48:48 +02001768 Convert MTRR layout from continuous to discrete, so X drivers can
1769 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001770
Thomas Gleixneraba37282008-07-15 14:48:48 +02001771 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001772 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001773 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001774
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001775 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001776
1777config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001778 int "MTRR cleanup enable value (0-1)"
1779 range 0 1
1780 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001781 depends on MTRR_SANITIZER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001782 help
Yinghai Luf5098d62008-04-29 20:25:58 -07001783 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001784
Yinghai Lu12031a62008-05-02 02:40:22 -07001785config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1786 int "MTRR cleanup spare reg num (0-7)"
1787 range 0 7
1788 default "1"
1789 depends on MTRR_SANITIZER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001790 help
Yinghai Lu12031a62008-05-02 02:40:22 -07001791 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001792 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001793
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001794config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001795 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001796 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001797 depends on MTRR
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001798 help
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001799 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001800
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001801 PATs are the modern equivalents of MTRRs and are much more
1802 flexible than MTRRs.
1803
1804 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001805 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001806
1807 If unsure, say Y.
1808
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001809config ARCH_USES_PG_UNCACHED
1810 def_bool y
1811 depends on X86_PAT
1812
H. Peter Anvin628c6242011-07-31 13:59:29 -07001813config ARCH_RANDOM
1814 def_bool y
1815 prompt "x86 architectural random number generator" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001816 help
H. Peter Anvin628c6242011-07-31 13:59:29 -07001817 Enable the x86 architectural RDRAND instruction
1818 (Intel Bull Mountain technology) to generate random numbers.
1819 If supported, this is a high bandwidth, cryptographically
1820 secure hardware random number generator.
1821
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001822config X86_SMAP
1823 def_bool y
1824 prompt "Supervisor Mode Access Prevention" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001825 help
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001826 Supervisor Mode Access Prevention (SMAP) is a security
1827 feature in newer Intel processors. There is a small
1828 performance cost if this enabled and turned on; there is
1829 also a small increase in the kernel size if this is enabled.
1830
1831 If unsure, say Y.
1832
Babu Mogerb9718802019-11-05 21:25:32 +00001833config X86_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001834 def_bool y
Babu Mogerb9718802019-11-05 21:25:32 +00001835 prompt "User Mode Instruction Prevention" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001836 help
Babu Mogerb9718802019-11-05 21:25:32 +00001837 User Mode Instruction Prevention (UMIP) is a security feature in
1838 some x86 processors. If enabled, a general protection fault is
1839 issued if the SGDT, SLDT, SIDT, SMSW or STR instructions are
1840 executed in user mode. These instructions unnecessarily expose
1841 information about the hardware state.
Ricardo Neri796ebc82017-11-13 22:29:42 -08001842
1843 The vast majority of applications do not use these instructions.
1844 For the very few that do, software emulation is provided in
1845 specific cases in protected and virtual-8086 modes. Emulated
1846 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001847
Dave Hansen35e97792016-02-12 13:02:00 -08001848config X86_INTEL_MEMORY_PROTECTION_KEYS
Babu Moger38f3e772020-05-28 11:08:23 -05001849 prompt "Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001850 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001851 # Note: only available in 64-bit mode
Babu Moger38f3e772020-05-28 11:08:23 -05001852 depends on X86_64 && (CPU_SUP_INTEL || CPU_SUP_AMD)
Ingo Molnar52c8e602016-11-15 10:15:03 +01001853 select ARCH_USES_HIGH_VMA_FLAGS
1854 select ARCH_HAS_PKEYS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001855 help
Dave Hansen284244a2016-02-12 13:02:28 -08001856 Memory Protection Keys provides a mechanism for enforcing
1857 page-based protections, but without requiring modification of the
1858 page tables when an application changes protection domains.
1859
Mauro Carvalho Chehab1eecbcd2019-06-07 15:54:31 -03001860 For details, see Documentation/core-api/protection-keys.rst
Dave Hansen284244a2016-02-12 13:02:28 -08001861
1862 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001863
Michal Hockodb616172019-10-23 12:35:50 +02001864choice
1865 prompt "TSX enable mode"
1866 depends on CPU_SUP_INTEL
1867 default X86_INTEL_TSX_MODE_OFF
1868 help
1869 Intel's TSX (Transactional Synchronization Extensions) feature
1870 allows to optimize locking protocols through lock elision which
1871 can lead to a noticeable performance boost.
1872
1873 On the other hand it has been shown that TSX can be exploited
1874 to form side channel attacks (e.g. TAA) and chances are there
1875 will be more of those attacks discovered in the future.
1876
1877 Therefore TSX is not enabled by default (aka tsx=off). An admin
1878 might override this decision by tsx=on the command line parameter.
1879 Even with TSX enabled, the kernel will attempt to enable the best
1880 possible TAA mitigation setting depending on the microcode available
1881 for the particular machine.
1882
1883 This option allows to set the default tsx mode between tsx=on, =off
1884 and =auto. See Documentation/admin-guide/kernel-parameters.txt for more
1885 details.
1886
1887 Say off if not sure, auto if TSX is in use but it should be used on safe
1888 platforms or on if TSX is in use and the security aspect of tsx is not
1889 relevant.
1890
1891config X86_INTEL_TSX_MODE_OFF
1892 bool "off"
1893 help
1894 TSX is disabled if possible - equals to tsx=off command line parameter.
1895
1896config X86_INTEL_TSX_MODE_ON
1897 bool "on"
1898 help
1899 TSX is always enabled on TSX capable HW - equals the tsx=on command
1900 line parameter.
1901
1902config X86_INTEL_TSX_MODE_AUTO
1903 bool "auto"
1904 help
1905 TSX is enabled on TSX capable HW that is believed to be safe against
1906 side channel attacks- equals the tsx=auto command line parameter.
1907endchoice
1908
Sean Christophersone7e05452020-11-13 00:01:16 +02001909config X86_SGX
1910 bool "Software Guard eXtensions (SGX)"
1911 depends on X86_64 && CPU_SUP_INTEL
1912 depends on CRYPTO=y
1913 depends on CRYPTO_SHA256=y
1914 select SRCU
1915 select MMU_NOTIFIER
Jarkko Sakkinen901ddbb2021-03-18 01:53:31 +02001916 select NUMA_KEEP_MEMINFO if NUMA
Sean Christophersone7e05452020-11-13 00:01:16 +02001917 help
1918 Intel(R) Software Guard eXtensions (SGX) is a set of CPU instructions
1919 that can be used by applications to set aside private regions of code
1920 and data, referred to as enclaves. An enclave's private memory can
1921 only be accessed by code running within the enclave. Accesses from
1922 outside the enclave, including other enclaves, are disallowed by
1923 hardware.
1924
1925 If unsure, say N.
1926
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001927config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001928 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001929 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001930 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001931 select EFI_RUNTIME_WRAPPERS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001932 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001933 This enables the kernel to use EFI runtime services that are
1934 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001935
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001936 This option is only useful on systems that have EFI firmware.
1937 In addition, you should use the latest ELILO loader available
1938 at <http://elilo.sourceforge.net> in order to take advantage
1939 of EFI runtime services. However, even with this option, the
1940 resultant kernel should continue to boot on existing non-EFI
1941 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001942
Matt Fleming291f3632011-12-12 21:27:52 +00001943config EFI_STUB
Ard Biesheuvel8f24f8c2019-12-24 16:10:12 +01001944 bool "EFI stub support"
1945 depends on EFI && !X86_USE_3DNOW
1946 depends on $(cc-option,-mabi=ms) || X86_32
1947 select RELOCATABLE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001948 help
Ard Biesheuvel8f24f8c2019-12-24 16:10:12 +01001949 This kernel feature allows a bzImage to be loaded directly
Matt Fleming291f3632011-12-12 21:27:52 +00001950 by EFI firmware without the use of a bootloader.
1951
Mauro Carvalho Chehab4f4cfa62019-06-27 14:56:51 -03001952 See Documentation/admin-guide/efi-stub.rst for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001953
Matt Fleming7d453ee2014-01-10 18:52:06 +00001954config EFI_MIXED
1955 bool "EFI mixed-mode support"
1956 depends on EFI_STUB && X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001957 help
Matt Fleming7d453ee2014-01-10 18:52:06 +00001958 Enabling this feature allows a 64-bit kernel to be booted
1959 on a 32-bit firmware, provided that your CPU supports 64-bit
1960 mode.
1961
1962 Note that it is not possible to boot a mixed-mode enabled
1963 kernel via the EFI boot stub - a bootloader that supports
1964 the EFI handover protocol must be used.
1965
1966 If unsure, say N.
1967
Masahiro Yamada8636a1f2018-12-11 20:01:04 +09001968source "kernel/Kconfig.hz"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001969
1970config KEXEC
1971 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001972 select KEXEC_CORE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001973 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001974 kexec is a system call that implements the ability to shutdown your
1975 current kernel, and to start another kernel. It is like a reboot
1976 but it is independent of the system firmware. And like a reboot
1977 you can start any kernel with it, not just Linux.
1978
1979 The name comes from the similarity to the exec system call.
1980
1981 It is an ongoing process to be certain the hardware in a machine
1982 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001983 initially work for you. As of this writing the exact hardware
1984 interface is strongly in flux, so no good recommendation can be
1985 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001986
Vivek Goyal74ca3172014-08-29 15:18:46 -07001987config KEXEC_FILE
1988 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07001989 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07001990 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07001991 depends on X86_64
1992 depends on CRYPTO=y
1993 depends on CRYPTO_SHA256=y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001994 help
Vivek Goyal74ca3172014-08-29 15:18:46 -07001995 This is new version of kexec system call. This system call is
1996 file based and takes file descriptors as system call argument
1997 for kernel and initramfs as opposed to list of segments as
1998 accepted by previous system call.
1999
AKASHI Takahirob799a092018-04-13 15:35:45 -07002000config ARCH_HAS_KEXEC_PURGATORY
2001 def_bool KEXEC_FILE
2002
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07002003config KEXEC_SIG
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002004 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07002005 depends on KEXEC_FILE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002006 help
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07002007
2008 This option makes the kexec_file_load() syscall check for a valid
2009 signature of the kernel image. The image can still be loaded without
2010 a valid signature unless you also enable KEXEC_SIG_FORCE, though if
2011 there's a signature that we can check, then it must be valid.
2012
2013 In addition to this option, you need to enable signature
2014 verification for the corresponding kernel image type being
2015 loaded in order for this to work.
2016
2017config KEXEC_SIG_FORCE
2018 bool "Require a valid signature in kexec_file_load() syscall"
2019 depends on KEXEC_SIG
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002020 help
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002021 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002022 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002023
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002024config KEXEC_BZIMAGE_VERIFY_SIG
2025 bool "Enable bzImage signature verification support"
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07002026 depends on KEXEC_SIG
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002027 depends on SIGNED_PE_FILE_VERIFICATION
2028 select SYSTEM_TRUSTED_KEYRING
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002029 help
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002030 Enable bzImage signature verification support.
2031
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002032config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002033 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002034 depends on X86_64 || (X86_32 && HIGHMEM)
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002035 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002036 Generate crash dump after being started by kexec.
2037 This should be normally only set in special crash dump kernels
2038 which are loaded in the main kernel with kexec-tools into
2039 a specially reserved region and then later executed after
2040 a crash by kdump/kexec. The crash dump kernel must be compiled
2041 to a memory address not used by the main kernel or BIOS using
2042 PHYSICAL_START, or it must be built as a relocatable image
2043 (CONFIG_RELOCATABLE=y).
Mauro Carvalho Chehab330d4812019-06-13 15:21:39 -03002044 For more details see Documentation/admin-guide/kdump/kdump.rst
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002045
Huang Ying3ab83522008-07-25 19:45:07 -07002046config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002047 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002048 depends on KEXEC && HIBERNATION
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002049 help
Huang Ying89081d12008-07-25 19:45:10 -07002050 Jump between original kernel and kexeced kernel and invoke
2051 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002052
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002053config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002054 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002055 default "0x1000000"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002056 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002057 This gives the physical address where the kernel is loaded.
2058
2059 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2060 bzImage will decompress itself to above physical address and
2061 run from there. Otherwise, bzImage will run from the address where
2062 it has been loaded by the boot loader and will ignore above physical
2063 address.
2064
2065 In normal kdump cases one does not have to set/change this option
2066 as now bzImage can be compiled as a completely relocatable image
2067 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2068 address. This option is mainly useful for the folks who don't want
2069 to use a bzImage for capturing the crash dump and want to use a
2070 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2071 to be specifically compiled to run from a specific memory area
2072 (normally a reserved region) and this option comes handy.
2073
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002074 So if you are using bzImage for capturing the crash dump,
2075 leave the value here unchanged to 0x1000000 and set
2076 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2077 for capturing the crash dump change this value to start of
2078 the reserved region. In other words, it can be set based on
2079 the "X" value as specified in the "crashkernel=YM@XM"
2080 command line boot parameter passed to the panic-ed
Mauro Carvalho Chehab330d4812019-06-13 15:21:39 -03002081 kernel. Please take a look at Documentation/admin-guide/kdump/kdump.rst
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002082 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002083
2084 Usage of bzImage for capturing the crash dump is recommended as
2085 one does not have to build two kernels. Same kernel can be used
2086 as production kernel and capture kernel. Above option should have
2087 gone away after relocatable bzImage support is introduced. But it
2088 is present because there are users out there who continue to use
2089 vmlinux for dump capture. This option should go away down the
2090 line.
2091
2092 Don't change this unless you know what you are doing.
2093
2094config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002095 bool "Build a relocatable kernel"
2096 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002097 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002098 This builds a kernel image that retains relocation information
2099 so it can be loaded someplace besides the default 1MB.
2100 The relocations tend to make the kernel binary about 10% larger,
2101 but are discarded at runtime.
2102
2103 One use is for the kexec on panic case where the recovery kernel
2104 must live at a different physical address than the primary
2105 kernel.
2106
2107 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2108 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002109 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002110
Kees Cook8ab38202013-10-10 17:18:14 -07002111config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002112 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002113 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002114 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002115 help
Baoquan Hee8581e32016-04-20 13:55:43 -07002116 In support of Kernel Address Space Layout Randomization (KASLR),
2117 this randomizes the physical address at which the kernel image
2118 is decompressed and the virtual address where the kernel
2119 image is mapped, as a security feature that deters exploit
2120 attempts relying on knowledge of the location of kernel
2121 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002122
Kees Cooked9f0072016-05-25 15:45:33 -07002123 On 64-bit, the kernel physical and virtual addresses are
2124 randomized separately. The physical address will be anywhere
2125 between 16MB and the top of physical memory (up to 64TB). The
2126 virtual address will be randomized from 16MB up to 1GB (9 bits
2127 of entropy). Note that this also reduces the memory space
2128 available to kernel modules from 1.5GB to 1GB.
2129
2130 On 32-bit, the kernel physical and virtual addresses are
2131 randomized together. They will be randomized from 16MB up to
2132 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002133
Baoquan Hee8581e32016-04-20 13:55:43 -07002134 Entropy is generated using the RDRAND instruction if it is
2135 supported. If RDTSC is supported, its value is mixed into
2136 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002137 supported, then entropy is read from the i8254 timer. The
2138 usable entropy is limited by the kernel being built using
2139 2GB addressing, and that PHYSICAL_ALIGN must be at a
2140 minimum of 2MB. As a result, only 10 bits of entropy are
2141 theoretically possible, but the implementations are further
2142 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002143
Ingo Molnar6807c842017-04-18 11:08:12 +02002144 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002145
2146# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002147config X86_NEED_RELOCS
2148 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002149 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002150
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002151config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002152 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002153 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002154 range 0x2000 0x1000000 if X86_32
2155 range 0x200000 0x1000000 if X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002156 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002157 This value puts the alignment restrictions on physical address
2158 where kernel is loaded and run from. Kernel is compiled for an
2159 address which meets above alignment restriction.
2160
2161 If bootloader loads the kernel at a non-aligned address and
2162 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2163 address aligned to above value and run from there.
2164
2165 If bootloader loads the kernel at a non-aligned address and
2166 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2167 load address and decompress itself to the address it has been
2168 compiled for and run from there. The address for which kernel is
2169 compiled already meets above alignment restrictions. Hence the
2170 end result is that kernel runs from a physical address meeting
2171 above alignment restrictions.
2172
Kees Cooka0215062013-07-08 09:15:17 -07002173 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2174 this value must be a multiple of 0x200000.
2175
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002176 Don't change this unless you know what you are doing.
2177
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002178config DYNAMIC_MEMORY_LAYOUT
2179 bool
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002180 help
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002181 This option makes base addresses of vmalloc and vmemmap as well as
2182 __PAGE_OFFSET movable during boot.
2183
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002184config RANDOMIZE_MEMORY
2185 bool "Randomize the kernel memory sections"
2186 depends on X86_64
2187 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002188 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002189 default RANDOMIZE_BASE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002190 help
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002191 Randomizes the base virtual address of kernel memory sections
2192 (physical memory mapping, vmalloc & vmemmap). This security feature
2193 makes exploits relying on predictable memory locations less reliable.
2194
2195 The order of allocations remains unchanged. Entropy is generated in
2196 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2197 configuration have in average 30,000 different possible virtual
2198 addresses for each memory section.
2199
Ingo Molnar6807c842017-04-18 11:08:12 +02002200 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002201
Thomas Garnier90397a42016-06-21 17:47:06 -07002202config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2203 hex "Physical memory mapping padding" if EXPERT
2204 depends on RANDOMIZE_MEMORY
2205 default "0xa" if MEMORY_HOTPLUG
2206 default "0x0"
2207 range 0x1 0x40 if MEMORY_HOTPLUG
2208 range 0x0 0x40
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002209 help
Thomas Garnier90397a42016-06-21 17:47:06 -07002210 Define the padding in terabytes added to the existing physical
2211 memory size during kernel memory randomization. It is useful
2212 for memory hotplug support but reduces the entropy available for
2213 address randomization.
2214
2215 If unsure, leave at the default value.
2216
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002217config HOTPLUG_CPU
Thomas Gleixnerbebd0242019-03-26 17:36:06 +01002218 def_bool y
Stephen Rothwell40b31362013-05-21 13:49:35 +10002219 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002220
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002221config BOOTPARAM_HOTPLUG_CPU0
2222 bool "Set default setting of cpu0_hotpluggable"
Kees Cook2c922cd2013-01-22 13:01:19 -08002223 depends on HOTPLUG_CPU
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002224 help
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002225 Set whether default state of cpu0_hotpluggable is on or off.
2226
2227 Say Y here to enable CPU0 hotplug by default. If this switch
2228 is turned on, there is no need to give cpu0_hotplug kernel
2229 parameter and the CPU0 hotplug feature is enabled by default.
2230
2231 Please note: there are two known CPU0 dependencies if you want
2232 to enable the CPU0 hotplug feature either by this switch or by
2233 cpu0_hotplug kernel parameter.
2234
2235 First, resume from hibernate or suspend always starts from CPU0.
2236 So hibernate and suspend are prevented if CPU0 is offline.
2237
2238 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2239 offline if any interrupt can not migrate out of CPU0. There may
2240 be other CPU0 dependencies.
2241
2242 Please make sure the dependencies are under your control before
2243 you enable this feature.
2244
2245 Say N if you don't want to enable CPU0 hotplug feature by default.
2246 You still can enable the CPU0 hotplug feature at boot by kernel
2247 parameter cpu0_hotplug.
2248
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002249config DEBUG_HOTPLUG_CPU0
2250 def_bool n
2251 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002252 depends on HOTPLUG_CPU
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002253 help
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002254 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2255 soon as possible and boots up userspace with CPU0 offlined. User
2256 can online CPU0 back after boot time.
2257
2258 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2259 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2260 compilation or giving cpu0_hotplug kernel parameter at boot.
2261
2262 If unsure, say N.
2263
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002264config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002265 def_bool n
2266 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002267 depends on COMPAT_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002268 help
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002269 Certain buggy versions of glibc will crash if they are
2270 presented with a 32-bit vDSO that is not mapped at the address
2271 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002272
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002273 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2274 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2275 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2276 the only released version with the bug, but OpenSUSE 9
2277 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002278
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002279 The symptom of the bug is that everything crashes on startup, saying:
2280 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2281
2282 Saying Y here changes the default value of the vdso32 boot
2283 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2284 This works around the glibc bug but hurts performance.
2285
2286 If unsure, say N: if you are compiling your own kernel, you
2287 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002288
Kees Cook3dc33bd2015-08-12 17:55:19 -07002289choice
2290 prompt "vsyscall table for legacy applications"
2291 depends on X86_64
Andy Lutomirski625b7b72019-06-26 21:45:07 -07002292 default LEGACY_VSYSCALL_XONLY
Kees Cook3dc33bd2015-08-12 17:55:19 -07002293 help
2294 Legacy user code that does not know how to find the vDSO expects
2295 to be able to issue three syscalls by calling fixed addresses in
2296 kernel space. Since this location is not randomized with ASLR,
2297 it can be used to assist security vulnerability exploitation.
2298
2299 This setting can be changed at boot time via the kernel command
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002300 line parameter vsyscall=[emulate|xonly|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002301
2302 On a system with recent enough glibc (2.14 or newer) and no
2303 static binaries, you can say None without a performance penalty
2304 to improve security.
2305
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002306 If unsure, select "Emulate execution only".
Kees Cook3dc33bd2015-08-12 17:55:19 -07002307
Kees Cook3dc33bd2015-08-12 17:55:19 -07002308 config LEGACY_VSYSCALL_EMULATE
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002309 bool "Full emulation"
Kees Cook3dc33bd2015-08-12 17:55:19 -07002310 help
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002311 The kernel traps and emulates calls into the fixed vsyscall
2312 address mapping. This makes the mapping non-executable, but
2313 it still contains readable known contents, which could be
2314 used in certain rare security vulnerability exploits. This
2315 configuration is recommended when using legacy userspace
2316 that still uses vsyscalls along with legacy binary
2317 instrumentation tools that require code to be readable.
2318
2319 An example of this type of legacy userspace is running
2320 Pin on an old binary that still uses vsyscalls.
2321
2322 config LEGACY_VSYSCALL_XONLY
2323 bool "Emulate execution only"
2324 help
2325 The kernel traps and emulates calls into the fixed vsyscall
2326 address mapping and does not allow reads. This
2327 configuration is recommended when userspace might use the
2328 legacy vsyscall area but support for legacy binary
2329 instrumentation of legacy code is not needed. It mitigates
2330 certain uses of the vsyscall area as an ASLR-bypassing
2331 buffer.
Kees Cook3dc33bd2015-08-12 17:55:19 -07002332
2333 config LEGACY_VSYSCALL_NONE
2334 bool "None"
2335 help
2336 There will be no vsyscall mapping at all. This will
2337 eliminate any risk of ASLR bypass due to the vsyscall
2338 fixed address mapping. Attempts to use the vsyscalls
2339 will be reported to dmesg, so that either old or
2340 malicious userspace programs can be identified.
2341
2342endchoice
2343
Tim Bird516cbf32008-08-12 12:52:36 -07002344config CMDLINE_BOOL
2345 bool "Built-in kernel command line"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002346 help
Tim Bird516cbf32008-08-12 12:52:36 -07002347 Allow for specifying boot arguments to the kernel at
2348 build time. On some systems (e.g. embedded ones), it is
2349 necessary or convenient to provide some or all of the
2350 kernel boot arguments with the kernel itself (that is,
2351 to not rely on the boot loader to provide them.)
2352
2353 To compile command line arguments into the kernel,
2354 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002355 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002356
2357 Systems with fully functional boot loaders (i.e. non-embedded)
2358 should leave this option set to 'N'.
2359
2360config CMDLINE
2361 string "Built-in kernel command string"
2362 depends on CMDLINE_BOOL
2363 default ""
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002364 help
Tim Bird516cbf32008-08-12 12:52:36 -07002365 Enter arguments here that should be compiled into the kernel
2366 image and used at boot time. If the boot loader provides a
2367 command line at boot time, it is appended to this string to
2368 form the full kernel command line, when the system boots.
2369
2370 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2371 change this behavior.
2372
2373 In most cases, the command line (whether built-in or provided
2374 by the boot loader) should specify the device for the root
2375 file system.
2376
2377config CMDLINE_OVERRIDE
2378 bool "Built-in command line overrides boot loader arguments"
Anders Roxell645e6462020-01-24 12:46:15 +01002379 depends on CMDLINE_BOOL && CMDLINE != ""
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002380 help
Tim Bird516cbf32008-08-12 12:52:36 -07002381 Set this option to 'Y' to have the kernel ignore the boot loader
2382 command line, and use ONLY the built-in command line.
2383
2384 This is used to work around broken boot loaders. This should
2385 be set to 'N' under normal conditions.
2386
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002387config MODIFY_LDT_SYSCALL
2388 bool "Enable the LDT (local descriptor table)" if EXPERT
2389 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002390 help
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002391 Linux can allow user programs to install a per-process x86
2392 Local Descriptor Table (LDT) using the modify_ldt(2) system
2393 call. This is required to run 16-bit or segmented code such as
2394 DOSEMU or some Wine programs. It is also used by some very old
2395 threading libraries.
2396
2397 Enabling this feature adds a small amount of overhead to
2398 context switches and increases the low-level kernel attack
2399 surface. Disabling it removes the modify_ldt(2) system call.
2400
2401 Saying 'N' here may make sense for embedded or server kernels.
2402
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002403source "kernel/livepatch/Kconfig"
2404
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002405endmenu
2406
Michal Hocko3072e412017-09-08 16:11:39 -07002407config ARCH_HAS_ADD_PAGES
2408 def_bool y
2409 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2410
Oscar Salvadorf91ef222021-05-04 18:39:51 -07002411config ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
2412 def_bool y
2413
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002414config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002415 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002416 depends on NUMA
2417
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002418menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002419
2420config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002421 def_bool y
Zhimin Gu44556532018-09-21 14:27:29 +08002422 depends on HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002423
2424source "kernel/power/Kconfig"
2425
2426source "drivers/acpi/Kconfig"
2427
Andi Kleena6b68072008-01-30 13:32:49 +01002428config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002429 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002430 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002431
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002432menuconfig APM
2433 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002434 depends on X86_32 && PM_SLEEP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002435 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002436 APM is a BIOS specification for saving power using several different
2437 techniques. This is mostly useful for battery powered laptops with
2438 APM compliant BIOSes. If you say Y here, the system time will be
2439 reset after a RESUME operation, the /proc/apm device will provide
2440 battery status information, and user-space programs will receive
2441 notification of APM "events" (e.g. battery status change).
2442
2443 If you select "Y" here, you can disable actual use of the APM
2444 BIOS by passing the "apm=off" option to the kernel at boot time.
2445
2446 Note that the APM support is almost completely disabled for
2447 machines with more than one CPU.
2448
2449 In order to use APM, you will need supporting software. For location
Mauro Carvalho Chehab151f4e22019-06-13 07:10:36 -03002450 and more information, read <file:Documentation/power/apm-acpi.rst>
Michael Witten2dc98fd2011-07-08 21:11:16 +00002451 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002452 <http://www.tldp.org/docs.html#howto>.
2453
2454 This driver does not spin down disk drives (see the hdparm(8)
2455 manpage ("man 8 hdparm") for that), and it doesn't turn off
2456 VESA-compliant "green" monitors.
2457
2458 This driver does not support the TI 4000M TravelMate and the ACER
2459 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2460 desktop machines also don't have compliant BIOSes, and this driver
2461 may cause those machines to panic during the boot phase.
2462
2463 Generally, if you don't have a battery in your machine, there isn't
2464 much point in using this driver and you should say N. If you get
2465 random kernel OOPSes or reboots that don't seem to be related to
2466 anything, try disabling/enabling this option (or disabling/enabling
2467 APM in your BIOS).
2468
2469 Some other things you should try when experiencing seemingly random,
2470 "weird" problems:
2471
2472 1) make sure that you have enough swap space and that it is
2473 enabled.
2474 2) pass the "no-hlt" option to the kernel
2475 3) switch on floating point emulation in the kernel and pass
2476 the "no387" option to the kernel
2477 4) pass the "floppy=nodma" option to the kernel
2478 5) pass the "mem=4M" option to the kernel (thereby disabling
2479 all but the first 4 MB of RAM)
2480 6) make sure that the CPU is not over clocked.
2481 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2482 8) disable the cache from your BIOS settings
2483 9) install a fan for the video card or exchange video RAM
2484 10) install a better fan for the CPU
2485 11) exchange RAM chips
2486 12) exchange the motherboard.
2487
2488 To compile this driver as a module, choose M here: the
2489 module will be called apm.
2490
2491if APM
2492
2493config APM_IGNORE_USER_SUSPEND
2494 bool "Ignore USER SUSPEND"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002495 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002496 This option will ignore USER SUSPEND requests. On machines with a
2497 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2498 series notebooks, it is necessary to say Y because of a BIOS bug.
2499
2500config APM_DO_ENABLE
2501 bool "Enable PM at boot time"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002502 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002503 Enable APM features at boot time. From page 36 of the APM BIOS
2504 specification: "When disabled, the APM BIOS does not automatically
2505 power manage devices, enter the Standby State, enter the Suspend
2506 State, or take power saving steps in response to CPU Idle calls."
2507 This driver will make CPU Idle calls when Linux is idle (unless this
2508 feature is turned off -- see "Do CPU IDLE calls", below). This
2509 should always save battery power, but more complicated APM features
2510 will be dependent on your BIOS implementation. You may need to turn
2511 this option off if your computer hangs at boot time when using APM
2512 support, or if it beeps continuously instead of suspending. Turn
2513 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2514 T400CDT. This is off by default since most machines do fine without
2515 this feature.
2516
2517config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002518 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002519 bool "Make CPU Idle calls when idle"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002520 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002521 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2522 On some machines, this can activate improved power savings, such as
2523 a slowed CPU clock rate, when the machine is idle. These idle calls
2524 are made after the idle loop has run for some length of time (e.g.,
2525 333 mS). On some machines, this will cause a hang at boot time or
2526 whenever the CPU becomes idle. (On machines with more than one CPU,
2527 this option does nothing.)
2528
2529config APM_DISPLAY_BLANK
2530 bool "Enable console blanking using APM"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002531 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002532 Enable console blanking using the APM. Some laptops can use this to
2533 turn off the LCD backlight when the screen blanker of the Linux
2534 virtual console blanks the screen. Note that this is only used by
2535 the virtual console screen blanker, and won't turn off the backlight
2536 when using the X Window system. This also doesn't have anything to
2537 do with your VESA-compliant power-saving monitor. Further, this
2538 option doesn't work for all laptops -- it might not turn off your
2539 backlight at all, or it might print a lot of errors to the console,
2540 especially if you are using gpm.
2541
2542config APM_ALLOW_INTS
2543 bool "Allow interrupts during APM BIOS calls"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002544 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002545 Normally we disable external interrupts while we are making calls to
2546 the APM BIOS as a measure to lessen the effects of a badly behaving
2547 BIOS implementation. The BIOS should reenable interrupts if it
2548 needs to. Unfortunately, some BIOSes do not -- especially those in
2549 many of the newer IBM Thinkpads. If you experience hangs when you
2550 suspend, try setting this to Y. Otherwise, say N.
2551
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002552endif # APM
2553
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002554source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002555
2556source "drivers/cpuidle/Kconfig"
2557
Andy Henroid27471fd2008-10-09 11:45:22 -07002558source "drivers/idle/Kconfig"
2559
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002560endmenu
2561
2562
2563menu "Bus options (PCI etc.)"
2564
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002565choice
2566 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002567 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002568 default PCI_GOANY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002569 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002570 On PCI systems, the BIOS can be used to detect the PCI devices and
2571 determine their configuration. However, some old PCI motherboards
2572 have BIOS bugs and may crash if this is done. Also, some embedded
2573 PCI-based systems don't have any BIOS at all. Linux can also try to
2574 detect the PCI hardware directly without using the BIOS.
2575
2576 With this option, you can specify how Linux should detect the
2577 PCI devices. If you choose "BIOS", the BIOS will be used,
2578 if you choose "Direct", the BIOS won't be used, and if you
2579 choose "MMConfig", then PCI Express MMCONFIG will be used.
2580 If you choose "Any", the kernel will try MMCONFIG, then the
2581 direct access method and falls back to the BIOS if that doesn't
2582 work. If unsure, go with the default, which is "Any".
2583
2584config PCI_GOBIOS
2585 bool "BIOS"
2586
2587config PCI_GOMMCONFIG
2588 bool "MMConfig"
2589
2590config PCI_GODIRECT
2591 bool "Direct"
2592
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002593config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002594 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002595 depends on OLPC
2596
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002597config PCI_GOANY
2598 bool "Any"
2599
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002600endchoice
2601
2602config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002603 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002604 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002605
2606# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2607config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002608 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002609 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002610
2611config PCI_MMCONFIG
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002612 bool "Support mmconfig PCI config space access" if X86_64
2613 default y
Andy Shevchenko4590d982021-02-11 15:40:02 +02002614 depends on PCI && (ACPI || JAILHOUSE_GUEST)
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002615 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002616
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002617config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002618 def_bool y
2619 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002620
Alex Nixonb5401a92010-03-18 16:31:34 -04002621config PCI_XEN
2622 def_bool y
2623 depends on PCI && XEN
Alex Nixonb5401a92010-03-18 16:31:34 -04002624
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002625config MMCONF_FAM10H
2626 def_bool y
2627 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002628
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002629config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002630 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002631 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002632 help
2633 Read the PCI windows out of the CNB20LE host bridge. This allows
2634 PCI hotplug to work on systems with the CNB20LE chipset which do
2635 not have ACPI.
2636
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002637 There's no public spec for this chipset, and this functionality
2638 is known to be incomplete.
2639
2640 You should say N unless you know you need this.
2641
William Breathitt Gray3a495512016-05-27 18:08:27 -04002642config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002643 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002644 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002645 Expose ISA bus device drivers and options available for selection and
2646 configuration. Enable this option if your target machine has an ISA
2647 bus. ISA is an older system, displaced by PCI and newer bus
2648 architectures -- if your target machine is modern, it probably does
2649 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002650
2651 If unsure, say N.
2652
David Rientjes1c00f012011-03-22 16:34:59 -07002653# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002654config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002655 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2656 default y
2657 help
2658 Enables ISA-style DMA support for devices requiring such controllers.
2659 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002660
Linus Torvalds51e68d02016-05-21 10:25:19 -07002661if X86_32
2662
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002663config ISA
2664 bool "ISA support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002665 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002666 Find out whether you have ISA slots on your motherboard. ISA is the
2667 name of a bus system, i.e. the way the CPU talks to the other stuff
2668 inside your box. Other bus systems are PCI, EISA, MicroChannel
2669 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2670 newer boards don't support it. If you have ISA, say Y, otherwise N.
2671
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002672config SCx200
2673 tristate "NatSemi SCx200 support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002674 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002675 This provides basic support for National Semiconductor's
2676 (now AMD's) Geode processors. The driver probes for the
2677 PCI-IDs of several on-chip devices, so its a good dependency
2678 for other scx200_* drivers.
2679
2680 If compiled as a module, the driver is named scx200.
2681
2682config SCx200HR_TIMER
2683 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002684 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002685 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002686 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002687 This driver provides a clocksource built upon the on-chip
2688 27MHz high-resolution timer. Its also a workaround for
2689 NSC Geode SC-1100's buggy TSC, which loses time when the
2690 processor goes idle (as is done by the scheduler). The
2691 other workaround is idle=poll boot option.
2692
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002693config OLPC
2694 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002695 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002696 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002697 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002698 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002699 select IRQ_DOMAIN
Lubomir Rintel0c3d9312019-05-13 09:56:37 +02002700 select OLPC_EC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002701 help
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002702 Add support for detecting the unique features of the OLPC
2703 XO hardware.
2704
Daniel Drakea3128582011-06-25 17:34:10 +01002705config OLPC_XO1_PM
2706 bool "OLPC XO-1 Power Management"
Borislav Petkovfa112cf2018-10-05 15:13:07 +02002707 depends on OLPC && MFD_CS5535=y && PM_SLEEP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002708 help
Daniel Drake97c4cb72011-06-25 17:34:11 +01002709 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002710
Daniel Drakecfee9592011-06-25 17:34:17 +01002711config OLPC_XO1_RTC
2712 bool "OLPC XO-1 Real Time Clock"
2713 depends on OLPC_XO1_PM && RTC_DRV_CMOS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002714 help
Daniel Drakecfee9592011-06-25 17:34:17 +01002715 Add support for the XO-1 real time clock, which can be used as a
2716 programmable wakeup source.
2717
Daniel Drake7feda8e2011-06-25 17:34:12 +01002718config OLPC_XO1_SCI
2719 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002720 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002721 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002722 select POWER_SUPPLY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002723 help
Daniel Drake7feda8e2011-06-25 17:34:12 +01002724 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002725 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002726 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002727 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002728 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002729 - AC adapter status updates
2730 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002731
Daniel Drakea0f30f52011-06-25 17:34:18 +01002732config OLPC_XO15_SCI
2733 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002734 depends on OLPC && ACPI
2735 select POWER_SUPPLY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002736 help
Daniel Drakea0f30f52011-06-25 17:34:18 +01002737 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2738 - EC-driven system wakeups
2739 - AC adapter status updates
2740 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002741
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002742config ALIX
2743 bool "PCEngines ALIX System Support (LED setup)"
2744 select GPIOLIB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002745 help
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002746 This option enables system support for the PCEngines ALIX.
2747 At present this just sets up LEDs for GPIO control on
2748 ALIX2/3/6 boards. However, other system specific setup should
2749 get added here.
2750
2751 Note: You must still enable the drivers for GPIO and LED support
2752 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2753
2754 Note: You have to set alix.force=1 for boards with Award BIOS.
2755
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002756config NET5501
2757 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2758 select GPIOLIB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002759 help
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002760 This option enables system support for the Soekris Engineering net5501.
2761
Philip A. Prindeville31970592012-01-14 01:45:39 -07002762config GEOS
2763 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2764 select GPIOLIB
2765 depends on DMI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002766 help
Philip A. Prindeville31970592012-01-14 01:45:39 -07002767 This option enables system support for the Traverse Technologies GEOS.
2768
Vivien Didelot7d029122013-01-04 16:18:14 -05002769config TS5500
2770 bool "Technologic Systems TS-5500 platform support"
2771 depends on MELAN
2772 select CHECK_SIGNATURE
2773 select NEW_LEDS
2774 select LEDS_CLASS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002775 help
Vivien Didelot7d029122013-01-04 16:18:14 -05002776 This option enables system support for the Technologic Systems TS-5500.
2777
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002778endif # X86_32
2779
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002780config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002781 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002782 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002783
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002784endmenu
2785
2786
Christoph Hellwig15724972018-07-31 13:39:30 +02002787menu "Binary Emulations"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002788
2789config IA32_EMULATION
2790 bool "IA32 Emulation"
2791 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002792 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002793 select BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002794 select COMPAT_OLD_SIGACTION
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002795 help
H. J. Lu5fd92e62012-02-19 10:40:03 -08002796 Include code to run legacy 32-bit programs under a
2797 64-bit kernel. You should likely turn this on, unless you're
2798 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002799
2800config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002801 tristate "IA32 a.out support"
2802 depends on IA32_EMULATION
Borislav Petkoveac61652019-03-05 15:47:51 +01002803 depends on BROKEN
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002804 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002805 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002806
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002807config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002808 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002809 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002810 help
H. J. Lu5fd92e62012-02-19 10:40:03 -08002811 Include code to run binaries for the x32 native 32-bit ABI
2812 for 64-bit processors. An x32 process gets access to the
2813 full 64-bit register file and wide data path while leaving
2814 pointers at 32 bits for smaller memory footprint.
2815
2816 You will need a recent binutils (2.22 or later) with
2817 elf32_x86_64 support enabled to compile a kernel with this
2818 option set.
2819
Ingo Molnar953fee12016-11-15 10:22:52 +01002820config COMPAT_32
2821 def_bool y
2822 depends on IA32_EMULATION || X86_32
2823 select HAVE_UID16
2824 select OLD_SIGSUSPEND3
2825
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002826config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002827 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002828 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002829
Jan Beulich3120e252012-09-10 12:41:45 +01002830if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002831config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002832 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002833
2834config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002835 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002836 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002837endif
David Howellsee009e4a02011-03-07 15:06:20 +00002838
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002839endmenu
2840
2841
Keith Packarde5beae12008-11-03 18:21:45 +01002842config HAVE_ATOMIC_IOMAP
2843 def_bool y
2844 depends on X86_32
2845
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002846source "drivers/firmware/Kconfig"
2847
Avi Kivityedf88412007-12-16 11:02:48 +02002848source "arch/x86/kvm/Kconfig"
Jason A. Donenfeld5e8ebd82020-03-26 17:00:58 +09002849
2850source "arch/x86/Kconfig.assembler"