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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
1004config SCHED_SMT
Thomas Gleixnerdbe73362018-11-25 19:33:37 +01001005 def_bool y if SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001006
1007config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001008 def_bool y
1009 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001010 depends on SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001011 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001012 Multi-core scheduler support improves the CPU scheduler's decision
1013 making when dealing with multi-core CPU chips at a cost of slightly
1014 increased overhead in some places. If unsure say N here.
1015
Tim Chende966cf2016-11-29 10:43:27 -08001016config SCHED_MC_PRIO
1017 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001018 depends on SCHED_MC && CPU_SUP_INTEL
1019 select X86_INTEL_PSTATE
1020 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001021 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001022 help
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001023 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1024 core ordering determined at manufacturing time, which allows
1025 certain cores to reach higher turbo frequencies (when running
1026 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001027
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001028 Enabling this kernel feature teaches the scheduler about
1029 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1030 scheduler's CPU selection logic accordingly, so that higher
1031 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001032
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001033 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001034
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001035 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001036
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001037config UP_LATE_INIT
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001038 def_bool y
1039 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001040
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001041config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001042 bool "Local APIC support on uniprocessors" if !PCI_MSI
1043 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001044 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001045 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001046 A local APIC (Advanced Programmable Interrupt Controller) is an
1047 integrated interrupt controller in the CPU. If you have a single-CPU
1048 system which has a processor with a local APIC, you can say Y here to
1049 enable and use it. If you say Y here even though your machine doesn't
1050 have a local APIC, then the kernel will still run with no slowdown at
1051 all. The local APIC supports CPU-generated self-interrupts (timer,
1052 performance counters), and the NMI watchdog which detects hard
1053 lockups.
1054
1055config X86_UP_IOAPIC
1056 bool "IO-APIC support on uniprocessors"
1057 depends on X86_UP_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001058 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001059 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1060 SMP-capable replacement for PC-style interrupt controllers. Most
1061 SMP systems and many recent uniprocessor systems have one.
1062
1063 If you have a single-CPU system with an IO-APIC, you can say Y here
1064 to use it. If you say Y here even though your machine doesn't have
1065 an IO-APIC, then the kernel will still run with no slowdown at all.
1066
1067config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001068 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001069 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001070 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001071 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001072
1073config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001074 def_bool y
1075 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001076
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001077config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1078 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001079 depends on X86_IO_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001080 help
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001081 This option enables a workaround that fixes a source of
1082 spurious interrupts. This is recommended when threaded
1083 interrupt handling is used on systems where the generation of
1084 superfluous "boot interrupts" cannot be disabled.
1085
1086 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1087 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1088 kernel does during interrupt handling). On chipsets where this
1089 boot IRQ generation cannot be disabled, this workaround keeps
1090 the original IRQ line masked so that only the equivalent "boot
1091 IRQ" is delivered to the CPUs. The workaround also tells the
1092 kernel to set up the IRQ handler on the boot IRQ line. In this
1093 way only one interrupt is delivered to the kernel. Otherwise
1094 the spurious second interrupt may cause the kernel to bring
1095 down (vital) interrupt lines.
1096
1097 Only affects "broken" chipsets. Interrupt sharing may be
1098 increased on these systems.
1099
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001100config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001101 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001102 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001103 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001104 help
Andi Kleenbab9bc62009-07-09 00:31:38 +02001105 Machine Check support allows the processor to notify the
1106 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001107 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001108 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001109
Tony Luck5de97c92017-03-27 11:33:03 +02001110config X86_MCELOG_LEGACY
1111 bool "Support for deprecated /dev/mcelog character device"
1112 depends on X86_MCE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001113 help
Tony Luck5de97c92017-03-27 11:33:03 +02001114 Enable support for /dev/mcelog which is needed by the old mcelog
1115 userspace logging daemon. Consider switching to the new generation
1116 rasdaemon solution.
1117
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001118config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001119 def_bool y
1120 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001121 depends on X86_MCE && X86_LOCAL_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001122 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001123 Additional support for intel specific MCE features such as
1124 the thermal monitor.
1125
1126config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001127 def_bool y
1128 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001129 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001130 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001131 Additional support for AMD specific MCE features such as
1132 the DRAM Error Threshold.
1133
Andi Kleen4efc0672009-04-28 19:07:31 +02001134config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001135 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001136 depends on X86_32 && X86_MCE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001137 help
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001138 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001139 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001140 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001141
Andi Kleenb2762682009-02-12 13:49:31 +01001142config X86_MCE_THRESHOLD
1143 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001144 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001145
Andi Kleenea149b32009-04-29 19:31:00 +02001146config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001147 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001148 tristate "Machine check injector support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001149 help
Andi Kleenea149b32009-04-29 19:31:00 +02001150 Provide support for injecting machine checks for testing purposes.
1151 If you don't know what a machine check is and you don't do kernel
1152 QA it is safe to say n.
1153
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001154source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001155
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001156config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001157 bool "Legacy VM86 support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001158 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001159 help
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001160 This option allows user programs to put the CPU into V8086
1161 mode, which is an 80286-era approximation of 16-bit real mode.
1162
1163 Some very old versions of X and/or vbetool require this option
1164 for user mode setting. Similarly, DOSEMU will use it if
1165 available to accelerate real mode DOS programs. However, any
1166 recent version of DOSEMU, X, or vbetool should be fully
1167 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001168 fall back to software emulation. Nevertheless, if you are using
1169 a 16-bit DOS program where 16-bit performance matters, vm86
1170 mode might be faster than emulation and you might want to
1171 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001172
Ingo Molnar1e642812015-09-05 08:58:10 +02001173 Note that any app that works on a 64-bit kernel is unlikely to
1174 need this option, as 64-bit kernels don't, and can't, support
1175 V8086 mode. This option is also unrelated to 16-bit protected
1176 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001177
Ingo Molnar1e642812015-09-05 08:58:10 +02001178 Enabling this option increases the complexity of the kernel
1179 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001180
Ingo Molnar1e642812015-09-05 08:58:10 +02001181 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001182
1183config VM86
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001184 bool
1185 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001186
1187config X86_16BIT
1188 bool "Enable support for 16-bit segments" if EXPERT
1189 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001190 depends on MODIFY_LDT_SYSCALL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001191 help
H. Peter Anvin34273f42014-05-04 10:36:22 -07001192 This option is required by programs like Wine to run 16-bit
1193 protected mode legacy code on x86 processors. Disabling
1194 this option saves about 300 bytes on i386, or around 6K text
1195 plus 16K runtime memory on x86-64,
1196
1197config X86_ESPFIX32
1198 def_bool y
1199 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001200
H. Peter Anvin197725d2014-05-04 10:00:49 -07001201config X86_ESPFIX64
1202 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001203 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001204
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001205config X86_VSYSCALL_EMULATION
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001206 bool "Enable vsyscall emulation" if EXPERT
1207 default y
1208 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001209 help
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001210 This enables emulation of the legacy vsyscall page. Disabling
1211 it is roughly equivalent to booting with vsyscall=none, except
1212 that it will also disable the helpful warning if a program
1213 tries to use a vsyscall. With this option set to N, offending
1214 programs will just segfault, citing addresses of the form
1215 0xffffffffff600?00.
1216
1217 This option is required by many programs built before 2013, and
1218 care should be used even with newer programs if set to N.
1219
1220 Disabling this option saves about 7K of kernel size and
1221 possibly 4K of additional runtime pagetable memory.
1222
Thomas Gleixner111e7b12019-11-12 21:40:33 +01001223config X86_IOPL_IOPERM
1224 bool "IOPERM and IOPL Emulation"
Thomas Gleixnera24ca992019-11-11 23:03:29 +01001225 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001226 help
Thomas Gleixner111e7b12019-11-12 21:40:33 +01001227 This enables the ioperm() and iopl() syscalls which are necessary
1228 for legacy applications.
1229
Thomas Gleixnerc8137ac2019-11-11 23:03:28 +01001230 Legacy IOPL support is an overbroad mechanism which allows user
1231 space aside of accessing all 65536 I/O ports also to disable
1232 interrupts. To gain this access the caller needs CAP_SYS_RAWIO
1233 capabilities and permission from potentially active security
1234 modules.
1235
1236 The emulation restricts the functionality of the syscall to
1237 only allowing the full range I/O port access, but prevents the
Thomas Gleixnera24ca992019-11-11 23:03:29 +01001238 ability to disable interrupts from user space which would be
1239 granted if the hardware IOPL mechanism would be used.
Thomas Gleixnerc8137ac2019-11-11 23:03:28 +01001240
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001241config TOSHIBA
1242 tristate "Toshiba Laptop support"
1243 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001244 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001245 This adds a driver to safely access the System Management Mode of
1246 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1247 not work on models with a Phoenix BIOS. The System Management Mode
1248 is used to set the BIOS and power saving options on Toshiba portables.
1249
1250 For information on utilities to make use of this driver see the
1251 Toshiba Linux utilities web site at:
1252 <http://www.buzzard.org.uk/toshiba/>.
1253
1254 Say Y if you intend to run this kernel on a Toshiba portable.
1255 Say N otherwise.
1256
1257config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001258 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001259 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001260 select SENSORS_DELL_SMM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001261 help
Pali Rohár039ae582015-05-14 13:16:37 +02001262 This option enables legacy /proc/i8k userspace interface in hwmon
1263 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1264 temperature and allows controlling fan speeds of Dell laptops via
1265 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1266 it reports also power and hotkey status. For fan speed control is
1267 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001268
Pali Rohár039ae582015-05-14 13:16:37 +02001269 Say Y if you intend to run this kernel on old Dell laptops or want to
1270 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001271 Say N otherwise.
1272
1273config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001274 bool "Enable X86 board specific fixups for reboot"
1275 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001276 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001277 This enables chipset and/or board specific fixups to be done
1278 in order to get reboot to work correctly. This is only needed on
1279 some combinations of hardware and BIOS. The symptom, for which
1280 this config is intended, is when reboot ends with a stalled/hung
1281 system.
1282
1283 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001284 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001285
1286 Say Y if you want to enable the fixup. Currently, it's safe to
1287 enable this option even if you don't need it.
1288 Say N otherwise.
1289
1290config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001291 bool "CPU microcode loading support"
1292 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001293 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001294 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001295 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001296 Intel and AMD processors. The Intel support is for the IA32 family,
1297 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1298 AMD support is for families 0x10 and later. You will obviously need
1299 the actual microcode binary data itself which is not shipped with
1300 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001301
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001302 The preferred method to load microcode from a detached initrd is described
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001303 in Documentation/x86/microcode.rst. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001304 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1305 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001306
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001307 In addition, you can build the microcode into the kernel. For that you
1308 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1309 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001310
Peter Oruba8d86f392008-07-28 18:44:21 +02001311config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001312 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001313 depends on MICROCODE
1314 default MICROCODE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001315 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001316 This options enables microcode patch loading support for Intel
1317 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001318
Alanb8989db2014-01-20 18:01:56 +00001319 For the current Intel microcode data package go to
1320 <https://downloadcenter.intel.com> and search for
1321 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001322
Peter Oruba80cc9f12008-07-28 18:44:22 +02001323config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001324 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001325 depends on MICROCODE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001326 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001327 If you select this option, microcode patch loading support for AMD
1328 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001329
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001330config MICROCODE_OLD_INTERFACE
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001331 bool "Ancient loading interface (DEPRECATED)"
1332 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001333 depends on MICROCODE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001334 help
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001335 DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface
1336 which was used by userspace tools like iucode_tool and microcode.ctl.
1337 It is inadequate because it runs too late to be able to properly
1338 load microcode on a machine and it needs special tools. Instead, you
1339 should've switched to the early loading method with the initrd or
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001340 builtin microcode by now: Documentation/x86/microcode.rst
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001341
1342config X86_MSR
1343 tristate "/dev/cpu/*/msr - Model-specific register support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001344 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001345 This device gives privileged processes access to the x86
1346 Model-Specific Registers (MSRs). It is a character device with
1347 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1348 MSR accesses are directed to a specific CPU on multi-processor
1349 systems.
1350
1351config X86_CPUID
1352 tristate "/dev/cpu/*/cpuid - CPU information support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001353 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001354 This device gives processes access to the x86 CPUID instruction to
1355 be executed on a specific processor. It is a character device
1356 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1357 /dev/cpu/31/cpuid.
1358
1359choice
1360 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001361 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001362 depends on X86_32
1363
1364config NOHIGHMEM
1365 bool "off"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001366 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001367 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1368 However, the address space of 32-bit x86 processors is only 4
1369 Gigabytes large. That means that, if you have a large amount of
1370 physical memory, not all of it can be "permanently mapped" by the
1371 kernel. The physical memory that's not permanently mapped is called
1372 "high memory".
1373
1374 If you are compiling a kernel which will never run on a machine with
1375 more than 1 Gigabyte total physical RAM, answer "off" here (default
1376 choice and suitable for most users). This will result in a "3GB/1GB"
1377 split: 3GB are mapped so that each process sees a 3GB virtual memory
1378 space and the remaining part of the 4GB virtual memory space is used
1379 by the kernel to permanently map as much physical memory as
1380 possible.
1381
1382 If the machine has between 1 and 4 Gigabytes physical RAM, then
1383 answer "4GB" here.
1384
1385 If more than 4 Gigabytes is used then answer "64GB" here. This
1386 selection turns Intel PAE (Physical Address Extension) mode on.
1387 PAE implements 3-level paging on IA32 processors. PAE is fully
1388 supported by Linux, PAE mode is implemented on all recent Intel
1389 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1390 then the kernel will not boot on CPUs that don't support PAE!
1391
1392 The actual amount of total physical memory will either be
1393 auto detected or can be forced by using a kernel command line option
1394 such as "mem=256M". (Try "man bootparam" or see the documentation of
1395 your boot loader (lilo or loadlin) about how to pass options to the
1396 kernel at boot time.)
1397
1398 If unsure, say "off".
1399
1400config HIGHMEM4G
1401 bool "4GB"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001402 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001403 Select this if you have a 32-bit processor and between 1 and 4
1404 gigabytes of physical RAM.
1405
1406config HIGHMEM64G
1407 bool "64GB"
Maciej W. Rozycki0ef34392021-04-14 12:38:28 +02001408 depends on !M486SX && !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001409 select X86_PAE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001410 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001411 Select this if you have a 32-bit processor and more than 4
1412 gigabytes of physical RAM.
1413
1414endchoice
1415
1416choice
David Rientjes6a108a12011-01-20 14:44:16 -08001417 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001418 default VMSPLIT_3G
1419 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001420 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001421 Select the desired split between kernel and user memory.
1422
1423 If the address range available to the kernel is less than the
1424 physical memory installed, the remaining memory will be available
1425 as "high memory". Accessing high memory is a little more costly
1426 than low memory, as it needs to be mapped into the kernel first.
1427 Note that increasing the kernel address space limits the range
1428 available to user programs, making the address space there
1429 tighter. Selecting anything other than the default 3G/1G split
1430 will also likely make your kernel incompatible with binary-only
1431 kernel modules.
1432
1433 If you are not absolutely sure what you are doing, leave this
1434 option alone!
1435
1436 config VMSPLIT_3G
1437 bool "3G/1G user/kernel split"
1438 config VMSPLIT_3G_OPT
1439 depends on !X86_PAE
1440 bool "3G/1G user/kernel split (for full 1G low memory)"
1441 config VMSPLIT_2G
1442 bool "2G/2G user/kernel split"
1443 config VMSPLIT_2G_OPT
1444 depends on !X86_PAE
1445 bool "2G/2G user/kernel split (for full 2G low memory)"
1446 config VMSPLIT_1G
1447 bool "1G/3G user/kernel split"
1448endchoice
1449
1450config PAGE_OFFSET
1451 hex
1452 default 0xB0000000 if VMSPLIT_3G_OPT
1453 default 0x80000000 if VMSPLIT_2G
1454 default 0x78000000 if VMSPLIT_2G_OPT
1455 default 0x40000000 if VMSPLIT_1G
1456 default 0xC0000000
1457 depends on X86_32
1458
1459config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001460 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001461 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001462
1463config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001464 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001465 depends on X86_32 && !HIGHMEM4G
Christoph Hellwigd4a451d2018-04-03 16:24:20 +02001466 select PHYS_ADDR_T_64BIT
Christian Melki9d99c712015-10-05 17:31:33 +02001467 select SWIOTLB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001468 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001469 PAE is required for NX support, and furthermore enables
1470 larger swapspace support for non-overcommit purposes. It
1471 has the cost of more pagetable lookup overhead, and also
1472 consumes more pagetable space per process.
1473
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001474config X86_5LEVEL
1475 bool "Enable 5-level page tables support"
Kirill A. Shutemov18ec1ea2019-09-13 12:54:52 +03001476 default y
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001477 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001478 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001479 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001480 help
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001481 5-level paging enables access to larger address space:
1482 upto 128 PiB of virtual address space and 4 PiB of
1483 physical address space.
1484
1485 It will be supported by future Intel CPUs.
1486
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001487 A kernel with the option enabled can be booted on machines that
1488 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001489
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001490 See Documentation/x86/x86_64/5level-paging.rst for more
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001491 information.
1492
1493 Say N if unsure.
1494
Ingo Molnar10971ab2015-03-05 08:18:23 +01001495config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001496 def_bool y
Vlastimil Babka2e1da132019-08-07 15:02:58 +02001497 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001498 help
Ingo Molnar10971ab2015-03-05 08:18:23 +01001499 Certain kernel features effectively disable kernel
1500 linear 1 GB mappings (even if the CPU otherwise
1501 supports them), so don't confuse the user by printing
1502 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001503
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001504config X86_CPA_STATISTICS
1505 bool "Enable statistic for Change Page Attribute"
1506 depends on DEBUG_FS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001507 help
Ingo Molnarb75baaf2019-11-20 15:57:04 +01001508 Expose statistics about the Change Page Attribute mechanism, which
Colin Ian Kinga9432452019-04-16 11:57:51 +01001509 helps to determine the effectiveness of preserving large and huge
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001510 page mappings when mapping protections are changed.
1511
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001512config AMD_MEM_ENCRYPT
1513 bool "AMD Secure Memory Encryption (SME) support"
1514 depends on X86_64 && CPU_SUP_AMD
David Rientjes82fef0a2020-04-14 17:05:01 -07001515 select DMA_COHERENT_POOL
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +03001516 select DYNAMIC_PHYSICAL_MASK
Ard Biesheuvelce9084b2019-02-02 10:41:17 +01001517 select ARCH_USE_MEMREMAP_PROT
Tom Lendacky9087c372019-07-10 19:01:19 +00001518 select ARCH_HAS_FORCE_DMA_UNENCRYPTED
Joerg Roedel597cfe482020-09-07 15:15:24 +02001519 select INSTRUCTION_DECODER
Tom Lendacky22916412021-03-04 16:40:11 -06001520 select ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001521 help
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001522 Say yes to enable support for the encryption of system memory.
1523 This requires an AMD processor that supports Secure Memory
1524 Encryption (SME).
1525
1526config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1527 bool "Activate AMD Secure Memory Encryption (SME) by default"
1528 default y
1529 depends on AMD_MEM_ENCRYPT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001530 help
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001531 Say yes to have system memory encrypted by default if running on
1532 an AMD processor that supports Secure Memory Encryption (SME).
1533
1534 If set to Y, then the encryption of system memory can be
1535 deactivated with the mem_encrypt=off command line option.
1536
1537 If set to N, then the encryption of system memory can be
1538 activated with the mem_encrypt=on command line option.
1539
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001540# Common NUMA Features
1541config NUMA
Randy Dunlape133f6e2019-12-03 16:06:47 -08001542 bool "NUMA Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001543 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001544 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1545 default y if X86_BIGSMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001546 help
Randy Dunlape133f6e2019-12-03 16:06:47 -08001547 Enable NUMA (Non-Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001548
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001549 The kernel will try to allocate memory used by a CPU on the
1550 local memory controller of the CPU and add some more
1551 NUMA awareness to the kernel.
1552
Ingo Molnarc280ea52008-11-08 13:29:45 +01001553 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001554 (or later), AMD Opteron, or EM64T NUMA.
1555
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001556 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001557 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001558
1559 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001560
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001561config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001562 def_bool y
1563 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001564 depends on X86_64 && NUMA && PCI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001565 help
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001566 Enable AMD NUMA node topology detection. You should say Y here if
1567 you have a multi processor AMD system. This uses an old method to
1568 read the NUMA configuration directly from the builtin Northbridge
1569 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1570 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001571
1572config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001573 def_bool y
1574 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001575 depends on X86_64 && NUMA && ACPI && PCI
1576 select ACPI_NUMA
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001577 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001578 Enable ACPI SRAT based node topology detection.
1579
1580config NUMA_EMU
1581 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001582 depends on NUMA
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001583 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001584 Enable NUMA emulation. A flat machine will be split
1585 into virtual nodes when booted with "numa=fake=N", where N is the
1586 number of nodes. This is only useful for debugging.
1587
1588config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001589 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001590 range 1 10
1591 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001592 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001593 default "3"
Mike Rapoporta9ee6cf2021-06-28 19:43:01 -07001594 depends on NUMA
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001595 help
Mike Travis1184dc22008-05-12 21:21:12 +02001596 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001597 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001598
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001599config ARCH_FLATMEM_ENABLE
1600 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001601 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001602
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001603config ARCH_SPARSEMEM_ENABLE
1604 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001605 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001606 select SPARSEMEM_STATIC if X86_32
1607 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1608
Tejun Heo3b166512011-04-01 11:15:12 +02001609config ARCH_SPARSEMEM_DEFAULT
Mike Rapoport6ad57f72019-04-24 16:24:11 +03001610 def_bool X86_64 || (NUMA && X86_32)
Tejun Heo3b166512011-04-01 11:15:12 +02001611
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001612config ARCH_SELECT_MEMORY_MODEL
1613 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001614 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001615
1616config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001617 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001618 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001619 help
1620 This option enables a sysfs memory/probe interface for testing.
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001621 See Documentation/admin-guide/mm/memory-hotplug.rst for more information.
Toshi Kania0842b72013-07-19 11:47:48 -06001622 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001623
Tejun Heo3b166512011-04-01 11:15:12 +02001624config ARCH_PROC_KCORE_TEXT
1625 def_bool y
1626 depends on X86_64 && PROC_KCORE
1627
Avi Kivitya29815a2010-01-10 16:28:09 +02001628config ILLEGAL_POINTER_VALUE
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001629 hex
1630 default 0 if X86_32
1631 default 0xdead000000000000 if X86_64
Avi Kivitya29815a2010-01-10 16:28:09 +02001632
Dan Williams7a678322015-08-19 00:34:34 -04001633config X86_PMEM_LEGACY_DEVICE
1634 bool
1635
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001636config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001637 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001638 depends on PHYS_ADDR_T_64BIT
1639 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001640 select X86_PMEM_LEGACY_DEVICE
Dan Williams7b27a862020-02-16 12:01:16 -08001641 select NUMA_KEEP_MEMINFO if NUMA
Dan Williams9f53f9f2015-06-09 15:33:45 -04001642 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001643 help
1644 Treat memory marked using the non-standard e820 type of 12 as used
1645 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1646 The kernel will offer these regions to the 'pmem' driver so
1647 they can be used for persistent storage.
1648
1649 Say Y if unsure.
1650
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001651config HIGHPTE
1652 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001653 depends on HIGHMEM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001654 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001655 The VM uses one page table entry for each page of physical memory.
1656 For systems with a lot of RAM, this can be wasteful of precious
1657 low memory. Setting this option will put user-space page table
1658 entries in high memory.
1659
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001660config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001661 bool "Check for low memory corruption"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001662 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001663 Periodically check for memory corruption in low memory, which
1664 is suspected to be caused by BIOS. Even when enabled in the
1665 configuration, it is disabled at runtime. Enable it by
1666 setting "memory_corruption_check=1" on the kernel command
1667 line. By default it scans the low 64k of memory every 60
1668 seconds; see the memory_corruption_check_size and
1669 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001670 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001671
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001672 When enabled with the default parameters, this option has
1673 almost no overhead, as it reserves a relatively small amount
1674 of memory and scans it infrequently. It both detects corruption
1675 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001676
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001677 It is, however, intended as a diagnostic tool; if repeatable
1678 BIOS-originated corruption always affects the same memory,
1679 you can use memmap= to prevent the kernel from using that
1680 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001681
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001682config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001683 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001684 depends on X86_CHECK_BIOS_CORRUPTION
1685 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001686 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001687 Set whether the default state of memory_corruption_check is
1688 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001689
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001690config MATH_EMULATION
1691 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001692 depends on MODIFY_LDT_SYSCALL
Arnd Bergmann87d60212019-10-01 16:23:35 +02001693 prompt "Math emulation" if X86_32 && (M486SX || MELAN)
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001694 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001695 Linux can emulate a math coprocessor (used for floating point
1696 operations) if you don't have one. 486DX and Pentium processors have
1697 a math coprocessor built in, 486SX and 386 do not, unless you added
1698 a 487DX or 387, respectively. (The messages during boot time can
1699 give you some hints here ["man dmesg"].) Everyone needs either a
1700 coprocessor or this emulation.
1701
1702 If you don't have a math coprocessor, you need to say Y here; if you
1703 say Y here even though you have a coprocessor, the coprocessor will
1704 be used nevertheless. (This behavior can be changed with the kernel
1705 command line option "no387", which comes handy if your coprocessor
1706 is broken. Try "man bootparam" or see the documentation of your boot
1707 loader (lilo or loadlin) about how to pass options to the kernel at
1708 boot time.) This means that it is a good idea to say Y here if you
1709 intend to use this kernel on different machines.
1710
1711 More information about the internals of the Linux math coprocessor
1712 emulation can be found in <file:arch/x86/math-emu/README>.
1713
1714 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1715 kernel, it won't hurt.
1716
1717config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001718 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001719 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001720 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001721 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1722 the Memory Type Range Registers (MTRRs) may be used to control
1723 processor access to memory ranges. This is most useful if you have
1724 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1725 allows bus write transfers to be combined into a larger transfer
1726 before bursting over the PCI/AGP bus. This can increase performance
1727 of image write operations 2.5 times or more. Saying Y here creates a
1728 /proc/mtrr file which may be used to manipulate your processor's
1729 MTRRs. Typically the X server should use this.
1730
1731 This code has a reasonably generic interface so that similar
1732 control registers on other processors can be easily supported
1733 as well:
1734
1735 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1736 Registers (ARRs) which provide a similar functionality to MTRRs. For
1737 these, the ARRs are used to emulate the MTRRs.
1738 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1739 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1740 write-combining. All of these processors are supported by this code
1741 and it makes sense to say Y here if you have one of them.
1742
1743 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1744 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1745 can lead to all sorts of problems, so it's good to say Y here.
1746
1747 You can safely say Y even if your machine doesn't have MTRRs, you'll
1748 just add about 9 KB to your kernel.
1749
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001750 See <file:Documentation/x86/mtrr.rst> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001751
Yinghai Lu95ffa242008-04-29 03:52:33 -07001752config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001753 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001754 prompt "MTRR cleanup support"
1755 depends on MTRR
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001756 help
Thomas Gleixneraba37282008-07-15 14:48:48 +02001757 Convert MTRR layout from continuous to discrete, so X drivers can
1758 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001759
Thomas Gleixneraba37282008-07-15 14:48:48 +02001760 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001761 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001762 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001763
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001764 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001765
1766config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001767 int "MTRR cleanup enable value (0-1)"
1768 range 0 1
1769 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001770 depends on MTRR_SANITIZER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001771 help
Yinghai Luf5098d62008-04-29 20:25:58 -07001772 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001773
Yinghai Lu12031a62008-05-02 02:40:22 -07001774config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1775 int "MTRR cleanup spare reg num (0-7)"
1776 range 0 7
1777 default "1"
1778 depends on MTRR_SANITIZER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001779 help
Yinghai Lu12031a62008-05-02 02:40:22 -07001780 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001781 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001782
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001783config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001784 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001785 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001786 depends on MTRR
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001787 help
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001788 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001789
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001790 PATs are the modern equivalents of MTRRs and are much more
1791 flexible than MTRRs.
1792
1793 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001794 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001795
1796 If unsure, say Y.
1797
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001798config ARCH_USES_PG_UNCACHED
1799 def_bool y
1800 depends on X86_PAT
1801
H. Peter Anvin628c6242011-07-31 13:59:29 -07001802config ARCH_RANDOM
1803 def_bool y
1804 prompt "x86 architectural random number generator" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001805 help
H. Peter Anvin628c6242011-07-31 13:59:29 -07001806 Enable the x86 architectural RDRAND instruction
1807 (Intel Bull Mountain technology) to generate random numbers.
1808 If supported, this is a high bandwidth, cryptographically
1809 secure hardware random number generator.
1810
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001811config X86_SMAP
1812 def_bool y
1813 prompt "Supervisor Mode Access Prevention" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001814 help
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001815 Supervisor Mode Access Prevention (SMAP) is a security
1816 feature in newer Intel processors. There is a small
1817 performance cost if this enabled and turned on; there is
1818 also a small increase in the kernel size if this is enabled.
1819
1820 If unsure, say Y.
1821
Babu Mogerb9718802019-11-05 21:25:32 +00001822config X86_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001823 def_bool y
Babu Mogerb9718802019-11-05 21:25:32 +00001824 prompt "User Mode Instruction Prevention" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001825 help
Babu Mogerb9718802019-11-05 21:25:32 +00001826 User Mode Instruction Prevention (UMIP) is a security feature in
1827 some x86 processors. If enabled, a general protection fault is
1828 issued if the SGDT, SLDT, SIDT, SMSW or STR instructions are
1829 executed in user mode. These instructions unnecessarily expose
1830 information about the hardware state.
Ricardo Neri796ebc82017-11-13 22:29:42 -08001831
1832 The vast majority of applications do not use these instructions.
1833 For the very few that do, software emulation is provided in
1834 specific cases in protected and virtual-8086 modes. Emulated
1835 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001836
Dave Hansen35e97792016-02-12 13:02:00 -08001837config X86_INTEL_MEMORY_PROTECTION_KEYS
Babu Moger38f3e772020-05-28 11:08:23 -05001838 prompt "Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001839 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001840 # Note: only available in 64-bit mode
Babu Moger38f3e772020-05-28 11:08:23 -05001841 depends on X86_64 && (CPU_SUP_INTEL || CPU_SUP_AMD)
Ingo Molnar52c8e602016-11-15 10:15:03 +01001842 select ARCH_USES_HIGH_VMA_FLAGS
1843 select ARCH_HAS_PKEYS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001844 help
Dave Hansen284244a2016-02-12 13:02:28 -08001845 Memory Protection Keys provides a mechanism for enforcing
1846 page-based protections, but without requiring modification of the
1847 page tables when an application changes protection domains.
1848
Mauro Carvalho Chehab1eecbcd2019-06-07 15:54:31 -03001849 For details, see Documentation/core-api/protection-keys.rst
Dave Hansen284244a2016-02-12 13:02:28 -08001850
1851 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001852
Michal Hockodb616172019-10-23 12:35:50 +02001853choice
1854 prompt "TSX enable mode"
1855 depends on CPU_SUP_INTEL
1856 default X86_INTEL_TSX_MODE_OFF
1857 help
1858 Intel's TSX (Transactional Synchronization Extensions) feature
1859 allows to optimize locking protocols through lock elision which
1860 can lead to a noticeable performance boost.
1861
1862 On the other hand it has been shown that TSX can be exploited
1863 to form side channel attacks (e.g. TAA) and chances are there
1864 will be more of those attacks discovered in the future.
1865
1866 Therefore TSX is not enabled by default (aka tsx=off). An admin
1867 might override this decision by tsx=on the command line parameter.
1868 Even with TSX enabled, the kernel will attempt to enable the best
1869 possible TAA mitigation setting depending on the microcode available
1870 for the particular machine.
1871
1872 This option allows to set the default tsx mode between tsx=on, =off
1873 and =auto. See Documentation/admin-guide/kernel-parameters.txt for more
1874 details.
1875
1876 Say off if not sure, auto if TSX is in use but it should be used on safe
1877 platforms or on if TSX is in use and the security aspect of tsx is not
1878 relevant.
1879
1880config X86_INTEL_TSX_MODE_OFF
1881 bool "off"
1882 help
1883 TSX is disabled if possible - equals to tsx=off command line parameter.
1884
1885config X86_INTEL_TSX_MODE_ON
1886 bool "on"
1887 help
1888 TSX is always enabled on TSX capable HW - equals the tsx=on command
1889 line parameter.
1890
1891config X86_INTEL_TSX_MODE_AUTO
1892 bool "auto"
1893 help
1894 TSX is enabled on TSX capable HW that is believed to be safe against
1895 side channel attacks- equals the tsx=auto command line parameter.
1896endchoice
1897
Sean Christophersone7e05452020-11-13 00:01:16 +02001898config X86_SGX
1899 bool "Software Guard eXtensions (SGX)"
1900 depends on X86_64 && CPU_SUP_INTEL
1901 depends on CRYPTO=y
1902 depends on CRYPTO_SHA256=y
1903 select SRCU
1904 select MMU_NOTIFIER
Jarkko Sakkinen901ddbb2021-03-18 01:53:31 +02001905 select NUMA_KEEP_MEMINFO if NUMA
Sean Christophersone7e05452020-11-13 00:01:16 +02001906 help
1907 Intel(R) Software Guard eXtensions (SGX) is a set of CPU instructions
1908 that can be used by applications to set aside private regions of code
1909 and data, referred to as enclaves. An enclave's private memory can
1910 only be accessed by code running within the enclave. Accesses from
1911 outside the enclave, including other enclaves, are disallowed by
1912 hardware.
1913
1914 If unsure, say N.
1915
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001916config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001917 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001918 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001919 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001920 select EFI_RUNTIME_WRAPPERS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001921 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001922 This enables the kernel to use EFI runtime services that are
1923 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001924
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001925 This option is only useful on systems that have EFI firmware.
1926 In addition, you should use the latest ELILO loader available
1927 at <http://elilo.sourceforge.net> in order to take advantage
1928 of EFI runtime services. However, even with this option, the
1929 resultant kernel should continue to boot on existing non-EFI
1930 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001931
Matt Fleming291f3632011-12-12 21:27:52 +00001932config EFI_STUB
Ard Biesheuvel8f24f8c2019-12-24 16:10:12 +01001933 bool "EFI stub support"
1934 depends on EFI && !X86_USE_3DNOW
1935 depends on $(cc-option,-mabi=ms) || X86_32
1936 select RELOCATABLE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001937 help
Ard Biesheuvel8f24f8c2019-12-24 16:10:12 +01001938 This kernel feature allows a bzImage to be loaded directly
Matt Fleming291f3632011-12-12 21:27:52 +00001939 by EFI firmware without the use of a bootloader.
1940
Mauro Carvalho Chehab4f4cfa62019-06-27 14:56:51 -03001941 See Documentation/admin-guide/efi-stub.rst for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001942
Matt Fleming7d453ee2014-01-10 18:52:06 +00001943config EFI_MIXED
1944 bool "EFI mixed-mode support"
1945 depends on EFI_STUB && X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001946 help
Matt Fleming7d453ee2014-01-10 18:52:06 +00001947 Enabling this feature allows a 64-bit kernel to be booted
1948 on a 32-bit firmware, provided that your CPU supports 64-bit
1949 mode.
1950
1951 Note that it is not possible to boot a mixed-mode enabled
1952 kernel via the EFI boot stub - a bootloader that supports
1953 the EFI handover protocol must be used.
1954
1955 If unsure, say N.
1956
Masahiro Yamada8636a1f2018-12-11 20:01:04 +09001957source "kernel/Kconfig.hz"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001958
1959config KEXEC
1960 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001961 select KEXEC_CORE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001962 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001963 kexec is a system call that implements the ability to shutdown your
1964 current kernel, and to start another kernel. It is like a reboot
1965 but it is independent of the system firmware. And like a reboot
1966 you can start any kernel with it, not just Linux.
1967
1968 The name comes from the similarity to the exec system call.
1969
1970 It is an ongoing process to be certain the hardware in a machine
1971 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001972 initially work for you. As of this writing the exact hardware
1973 interface is strongly in flux, so no good recommendation can be
1974 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001975
Vivek Goyal74ca3172014-08-29 15:18:46 -07001976config KEXEC_FILE
1977 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07001978 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07001979 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07001980 depends on X86_64
1981 depends on CRYPTO=y
1982 depends on CRYPTO_SHA256=y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001983 help
Vivek Goyal74ca3172014-08-29 15:18:46 -07001984 This is new version of kexec system call. This system call is
1985 file based and takes file descriptors as system call argument
1986 for kernel and initramfs as opposed to list of segments as
1987 accepted by previous system call.
1988
AKASHI Takahirob799a092018-04-13 15:35:45 -07001989config ARCH_HAS_KEXEC_PURGATORY
1990 def_bool KEXEC_FILE
1991
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07001992config KEXEC_SIG
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001993 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07001994 depends on KEXEC_FILE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001995 help
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07001996
1997 This option makes the kexec_file_load() syscall check for a valid
1998 signature of the kernel image. The image can still be loaded without
1999 a valid signature unless you also enable KEXEC_SIG_FORCE, though if
2000 there's a signature that we can check, then it must be valid.
2001
2002 In addition to this option, you need to enable signature
2003 verification for the corresponding kernel image type being
2004 loaded in order for this to work.
2005
2006config KEXEC_SIG_FORCE
2007 bool "Require a valid signature in kexec_file_load() syscall"
2008 depends on KEXEC_SIG
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002009 help
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002010 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002011 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002012
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002013config KEXEC_BZIMAGE_VERIFY_SIG
2014 bool "Enable bzImage signature verification support"
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07002015 depends on KEXEC_SIG
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002016 depends on SIGNED_PE_FILE_VERIFICATION
2017 select SYSTEM_TRUSTED_KEYRING
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002018 help
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002019 Enable bzImage signature verification support.
2020
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002021config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002022 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002023 depends on X86_64 || (X86_32 && HIGHMEM)
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002024 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002025 Generate crash dump after being started by kexec.
2026 This should be normally only set in special crash dump kernels
2027 which are loaded in the main kernel with kexec-tools into
2028 a specially reserved region and then later executed after
2029 a crash by kdump/kexec. The crash dump kernel must be compiled
2030 to a memory address not used by the main kernel or BIOS using
2031 PHYSICAL_START, or it must be built as a relocatable image
2032 (CONFIG_RELOCATABLE=y).
Mauro Carvalho Chehab330d4812019-06-13 15:21:39 -03002033 For more details see Documentation/admin-guide/kdump/kdump.rst
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002034
Huang Ying3ab83522008-07-25 19:45:07 -07002035config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002036 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002037 depends on KEXEC && HIBERNATION
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002038 help
Huang Ying89081d12008-07-25 19:45:10 -07002039 Jump between original kernel and kexeced kernel and invoke
2040 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002041
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002042config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002043 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002044 default "0x1000000"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002045 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002046 This gives the physical address where the kernel is loaded.
2047
2048 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2049 bzImage will decompress itself to above physical address and
2050 run from there. Otherwise, bzImage will run from the address where
2051 it has been loaded by the boot loader and will ignore above physical
2052 address.
2053
2054 In normal kdump cases one does not have to set/change this option
2055 as now bzImage can be compiled as a completely relocatable image
2056 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2057 address. This option is mainly useful for the folks who don't want
2058 to use a bzImage for capturing the crash dump and want to use a
2059 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2060 to be specifically compiled to run from a specific memory area
2061 (normally a reserved region) and this option comes handy.
2062
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002063 So if you are using bzImage for capturing the crash dump,
2064 leave the value here unchanged to 0x1000000 and set
2065 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2066 for capturing the crash dump change this value to start of
2067 the reserved region. In other words, it can be set based on
2068 the "X" value as specified in the "crashkernel=YM@XM"
2069 command line boot parameter passed to the panic-ed
Mauro Carvalho Chehab330d4812019-06-13 15:21:39 -03002070 kernel. Please take a look at Documentation/admin-guide/kdump/kdump.rst
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002071 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002072
2073 Usage of bzImage for capturing the crash dump is recommended as
2074 one does not have to build two kernels. Same kernel can be used
2075 as production kernel and capture kernel. Above option should have
2076 gone away after relocatable bzImage support is introduced. But it
2077 is present because there are users out there who continue to use
2078 vmlinux for dump capture. This option should go away down the
2079 line.
2080
2081 Don't change this unless you know what you are doing.
2082
2083config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002084 bool "Build a relocatable kernel"
2085 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002086 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002087 This builds a kernel image that retains relocation information
2088 so it can be loaded someplace besides the default 1MB.
2089 The relocations tend to make the kernel binary about 10% larger,
2090 but are discarded at runtime.
2091
2092 One use is for the kexec on panic case where the recovery kernel
2093 must live at a different physical address than the primary
2094 kernel.
2095
2096 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2097 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002098 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002099
Kees Cook8ab38202013-10-10 17:18:14 -07002100config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002101 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002102 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002103 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002104 help
Baoquan Hee8581e32016-04-20 13:55:43 -07002105 In support of Kernel Address Space Layout Randomization (KASLR),
2106 this randomizes the physical address at which the kernel image
2107 is decompressed and the virtual address where the kernel
2108 image is mapped, as a security feature that deters exploit
2109 attempts relying on knowledge of the location of kernel
2110 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002111
Kees Cooked9f0072016-05-25 15:45:33 -07002112 On 64-bit, the kernel physical and virtual addresses are
2113 randomized separately. The physical address will be anywhere
2114 between 16MB and the top of physical memory (up to 64TB). The
2115 virtual address will be randomized from 16MB up to 1GB (9 bits
2116 of entropy). Note that this also reduces the memory space
2117 available to kernel modules from 1.5GB to 1GB.
2118
2119 On 32-bit, the kernel physical and virtual addresses are
2120 randomized together. They will be randomized from 16MB up to
2121 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002122
Baoquan Hee8581e32016-04-20 13:55:43 -07002123 Entropy is generated using the RDRAND instruction if it is
2124 supported. If RDTSC is supported, its value is mixed into
2125 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002126 supported, then entropy is read from the i8254 timer. The
2127 usable entropy is limited by the kernel being built using
2128 2GB addressing, and that PHYSICAL_ALIGN must be at a
2129 minimum of 2MB. As a result, only 10 bits of entropy are
2130 theoretically possible, but the implementations are further
2131 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002132
Ingo Molnar6807c842017-04-18 11:08:12 +02002133 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002134
2135# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002136config X86_NEED_RELOCS
2137 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002138 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002139
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002140config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002141 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002142 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002143 range 0x2000 0x1000000 if X86_32
2144 range 0x200000 0x1000000 if X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002145 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002146 This value puts the alignment restrictions on physical address
2147 where kernel is loaded and run from. Kernel is compiled for an
2148 address which meets above alignment restriction.
2149
2150 If bootloader loads the kernel at a non-aligned address and
2151 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2152 address aligned to above value and run from there.
2153
2154 If bootloader loads the kernel at a non-aligned address and
2155 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2156 load address and decompress itself to the address it has been
2157 compiled for and run from there. The address for which kernel is
2158 compiled already meets above alignment restrictions. Hence the
2159 end result is that kernel runs from a physical address meeting
2160 above alignment restrictions.
2161
Kees Cooka0215062013-07-08 09:15:17 -07002162 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2163 this value must be a multiple of 0x200000.
2164
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002165 Don't change this unless you know what you are doing.
2166
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002167config DYNAMIC_MEMORY_LAYOUT
2168 bool
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002169 help
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002170 This option makes base addresses of vmalloc and vmemmap as well as
2171 __PAGE_OFFSET movable during boot.
2172
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002173config RANDOMIZE_MEMORY
2174 bool "Randomize the kernel memory sections"
2175 depends on X86_64
2176 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002177 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002178 default RANDOMIZE_BASE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002179 help
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002180 Randomizes the base virtual address of kernel memory sections
2181 (physical memory mapping, vmalloc & vmemmap). This security feature
2182 makes exploits relying on predictable memory locations less reliable.
2183
2184 The order of allocations remains unchanged. Entropy is generated in
2185 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2186 configuration have in average 30,000 different possible virtual
2187 addresses for each memory section.
2188
Ingo Molnar6807c842017-04-18 11:08:12 +02002189 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002190
Thomas Garnier90397a42016-06-21 17:47:06 -07002191config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2192 hex "Physical memory mapping padding" if EXPERT
2193 depends on RANDOMIZE_MEMORY
2194 default "0xa" if MEMORY_HOTPLUG
2195 default "0x0"
2196 range 0x1 0x40 if MEMORY_HOTPLUG
2197 range 0x0 0x40
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002198 help
Thomas Garnier90397a42016-06-21 17:47:06 -07002199 Define the padding in terabytes added to the existing physical
2200 memory size during kernel memory randomization. It is useful
2201 for memory hotplug support but reduces the entropy available for
2202 address randomization.
2203
2204 If unsure, leave at the default value.
2205
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002206config HOTPLUG_CPU
Thomas Gleixnerbebd0242019-03-26 17:36:06 +01002207 def_bool y
Stephen Rothwell40b31362013-05-21 13:49:35 +10002208 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002209
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002210config BOOTPARAM_HOTPLUG_CPU0
2211 bool "Set default setting of cpu0_hotpluggable"
Kees Cook2c922cd2013-01-22 13:01:19 -08002212 depends on HOTPLUG_CPU
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002213 help
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002214 Set whether default state of cpu0_hotpluggable is on or off.
2215
2216 Say Y here to enable CPU0 hotplug by default. If this switch
2217 is turned on, there is no need to give cpu0_hotplug kernel
2218 parameter and the CPU0 hotplug feature is enabled by default.
2219
2220 Please note: there are two known CPU0 dependencies if you want
2221 to enable the CPU0 hotplug feature either by this switch or by
2222 cpu0_hotplug kernel parameter.
2223
2224 First, resume from hibernate or suspend always starts from CPU0.
2225 So hibernate and suspend are prevented if CPU0 is offline.
2226
2227 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2228 offline if any interrupt can not migrate out of CPU0. There may
2229 be other CPU0 dependencies.
2230
2231 Please make sure the dependencies are under your control before
2232 you enable this feature.
2233
2234 Say N if you don't want to enable CPU0 hotplug feature by default.
2235 You still can enable the CPU0 hotplug feature at boot by kernel
2236 parameter cpu0_hotplug.
2237
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002238config DEBUG_HOTPLUG_CPU0
2239 def_bool n
2240 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002241 depends on HOTPLUG_CPU
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002242 help
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002243 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2244 soon as possible and boots up userspace with CPU0 offlined. User
2245 can online CPU0 back after boot time.
2246
2247 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2248 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2249 compilation or giving cpu0_hotplug kernel parameter at boot.
2250
2251 If unsure, say N.
2252
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002253config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002254 def_bool n
2255 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002256 depends on COMPAT_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002257 help
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002258 Certain buggy versions of glibc will crash if they are
2259 presented with a 32-bit vDSO that is not mapped at the address
2260 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002261
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002262 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2263 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2264 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2265 the only released version with the bug, but OpenSUSE 9
2266 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002267
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002268 The symptom of the bug is that everything crashes on startup, saying:
2269 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2270
2271 Saying Y here changes the default value of the vdso32 boot
2272 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2273 This works around the glibc bug but hurts performance.
2274
2275 If unsure, say N: if you are compiling your own kernel, you
2276 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002277
Kees Cook3dc33bd2015-08-12 17:55:19 -07002278choice
2279 prompt "vsyscall table for legacy applications"
2280 depends on X86_64
Andy Lutomirski625b7b72019-06-26 21:45:07 -07002281 default LEGACY_VSYSCALL_XONLY
Kees Cook3dc33bd2015-08-12 17:55:19 -07002282 help
2283 Legacy user code that does not know how to find the vDSO expects
2284 to be able to issue three syscalls by calling fixed addresses in
2285 kernel space. Since this location is not randomized with ASLR,
2286 it can be used to assist security vulnerability exploitation.
2287
2288 This setting can be changed at boot time via the kernel command
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002289 line parameter vsyscall=[emulate|xonly|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002290
2291 On a system with recent enough glibc (2.14 or newer) and no
2292 static binaries, you can say None without a performance penalty
2293 to improve security.
2294
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002295 If unsure, select "Emulate execution only".
Kees Cook3dc33bd2015-08-12 17:55:19 -07002296
Kees Cook3dc33bd2015-08-12 17:55:19 -07002297 config LEGACY_VSYSCALL_EMULATE
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002298 bool "Full emulation"
Kees Cook3dc33bd2015-08-12 17:55:19 -07002299 help
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002300 The kernel traps and emulates calls into the fixed vsyscall
2301 address mapping. This makes the mapping non-executable, but
2302 it still contains readable known contents, which could be
2303 used in certain rare security vulnerability exploits. This
2304 configuration is recommended when using legacy userspace
2305 that still uses vsyscalls along with legacy binary
2306 instrumentation tools that require code to be readable.
2307
2308 An example of this type of legacy userspace is running
2309 Pin on an old binary that still uses vsyscalls.
2310
2311 config LEGACY_VSYSCALL_XONLY
2312 bool "Emulate execution only"
2313 help
2314 The kernel traps and emulates calls into the fixed vsyscall
2315 address mapping and does not allow reads. This
2316 configuration is recommended when userspace might use the
2317 legacy vsyscall area but support for legacy binary
2318 instrumentation of legacy code is not needed. It mitigates
2319 certain uses of the vsyscall area as an ASLR-bypassing
2320 buffer.
Kees Cook3dc33bd2015-08-12 17:55:19 -07002321
2322 config LEGACY_VSYSCALL_NONE
2323 bool "None"
2324 help
2325 There will be no vsyscall mapping at all. This will
2326 eliminate any risk of ASLR bypass due to the vsyscall
2327 fixed address mapping. Attempts to use the vsyscalls
2328 will be reported to dmesg, so that either old or
2329 malicious userspace programs can be identified.
2330
2331endchoice
2332
Tim Bird516cbf32008-08-12 12:52:36 -07002333config CMDLINE_BOOL
2334 bool "Built-in kernel command line"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002335 help
Tim Bird516cbf32008-08-12 12:52:36 -07002336 Allow for specifying boot arguments to the kernel at
2337 build time. On some systems (e.g. embedded ones), it is
2338 necessary or convenient to provide some or all of the
2339 kernel boot arguments with the kernel itself (that is,
2340 to not rely on the boot loader to provide them.)
2341
2342 To compile command line arguments into the kernel,
2343 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002344 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002345
2346 Systems with fully functional boot loaders (i.e. non-embedded)
2347 should leave this option set to 'N'.
2348
2349config CMDLINE
2350 string "Built-in kernel command string"
2351 depends on CMDLINE_BOOL
2352 default ""
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002353 help
Tim Bird516cbf32008-08-12 12:52:36 -07002354 Enter arguments here that should be compiled into the kernel
2355 image and used at boot time. If the boot loader provides a
2356 command line at boot time, it is appended to this string to
2357 form the full kernel command line, when the system boots.
2358
2359 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2360 change this behavior.
2361
2362 In most cases, the command line (whether built-in or provided
2363 by the boot loader) should specify the device for the root
2364 file system.
2365
2366config CMDLINE_OVERRIDE
2367 bool "Built-in command line overrides boot loader arguments"
Anders Roxell645e6462020-01-24 12:46:15 +01002368 depends on CMDLINE_BOOL && CMDLINE != ""
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002369 help
Tim Bird516cbf32008-08-12 12:52:36 -07002370 Set this option to 'Y' to have the kernel ignore the boot loader
2371 command line, and use ONLY the built-in command line.
2372
2373 This is used to work around broken boot loaders. This should
2374 be set to 'N' under normal conditions.
2375
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002376config MODIFY_LDT_SYSCALL
2377 bool "Enable the LDT (local descriptor table)" if EXPERT
2378 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002379 help
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002380 Linux can allow user programs to install a per-process x86
2381 Local Descriptor Table (LDT) using the modify_ldt(2) system
2382 call. This is required to run 16-bit or segmented code such as
2383 DOSEMU or some Wine programs. It is also used by some very old
2384 threading libraries.
2385
2386 Enabling this feature adds a small amount of overhead to
2387 context switches and increases the low-level kernel attack
2388 surface. Disabling it removes the modify_ldt(2) system call.
2389
2390 Saying 'N' here may make sense for embedded or server kernels.
2391
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002392source "kernel/livepatch/Kconfig"
2393
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002394endmenu
2395
Michal Hocko3072e412017-09-08 16:11:39 -07002396config ARCH_HAS_ADD_PAGES
2397 def_bool y
2398 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2399
Oscar Salvadorf91ef222021-05-04 18:39:51 -07002400config ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
2401 def_bool y
2402
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002403config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002404 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002405 depends on NUMA
2406
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002407menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002408
2409config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002410 def_bool y
Zhimin Gu44556532018-09-21 14:27:29 +08002411 depends on HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002412
2413source "kernel/power/Kconfig"
2414
2415source "drivers/acpi/Kconfig"
2416
Andi Kleena6b68072008-01-30 13:32:49 +01002417config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002418 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002419 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002420
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002421menuconfig APM
2422 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002423 depends on X86_32 && PM_SLEEP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002424 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002425 APM is a BIOS specification for saving power using several different
2426 techniques. This is mostly useful for battery powered laptops with
2427 APM compliant BIOSes. If you say Y here, the system time will be
2428 reset after a RESUME operation, the /proc/apm device will provide
2429 battery status information, and user-space programs will receive
2430 notification of APM "events" (e.g. battery status change).
2431
2432 If you select "Y" here, you can disable actual use of the APM
2433 BIOS by passing the "apm=off" option to the kernel at boot time.
2434
2435 Note that the APM support is almost completely disabled for
2436 machines with more than one CPU.
2437
2438 In order to use APM, you will need supporting software. For location
Mauro Carvalho Chehab151f4e22019-06-13 07:10:36 -03002439 and more information, read <file:Documentation/power/apm-acpi.rst>
Michael Witten2dc98fd2011-07-08 21:11:16 +00002440 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002441 <http://www.tldp.org/docs.html#howto>.
2442
2443 This driver does not spin down disk drives (see the hdparm(8)
2444 manpage ("man 8 hdparm") for that), and it doesn't turn off
2445 VESA-compliant "green" monitors.
2446
2447 This driver does not support the TI 4000M TravelMate and the ACER
2448 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2449 desktop machines also don't have compliant BIOSes, and this driver
2450 may cause those machines to panic during the boot phase.
2451
2452 Generally, if you don't have a battery in your machine, there isn't
2453 much point in using this driver and you should say N. If you get
2454 random kernel OOPSes or reboots that don't seem to be related to
2455 anything, try disabling/enabling this option (or disabling/enabling
2456 APM in your BIOS).
2457
2458 Some other things you should try when experiencing seemingly random,
2459 "weird" problems:
2460
2461 1) make sure that you have enough swap space and that it is
2462 enabled.
2463 2) pass the "no-hlt" option to the kernel
2464 3) switch on floating point emulation in the kernel and pass
2465 the "no387" option to the kernel
2466 4) pass the "floppy=nodma" option to the kernel
2467 5) pass the "mem=4M" option to the kernel (thereby disabling
2468 all but the first 4 MB of RAM)
2469 6) make sure that the CPU is not over clocked.
2470 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2471 8) disable the cache from your BIOS settings
2472 9) install a fan for the video card or exchange video RAM
2473 10) install a better fan for the CPU
2474 11) exchange RAM chips
2475 12) exchange the motherboard.
2476
2477 To compile this driver as a module, choose M here: the
2478 module will be called apm.
2479
2480if APM
2481
2482config APM_IGNORE_USER_SUSPEND
2483 bool "Ignore USER SUSPEND"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002484 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002485 This option will ignore USER SUSPEND requests. On machines with a
2486 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2487 series notebooks, it is necessary to say Y because of a BIOS bug.
2488
2489config APM_DO_ENABLE
2490 bool "Enable PM at boot time"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002491 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002492 Enable APM features at boot time. From page 36 of the APM BIOS
2493 specification: "When disabled, the APM BIOS does not automatically
2494 power manage devices, enter the Standby State, enter the Suspend
2495 State, or take power saving steps in response to CPU Idle calls."
2496 This driver will make CPU Idle calls when Linux is idle (unless this
2497 feature is turned off -- see "Do CPU IDLE calls", below). This
2498 should always save battery power, but more complicated APM features
2499 will be dependent on your BIOS implementation. You may need to turn
2500 this option off if your computer hangs at boot time when using APM
2501 support, or if it beeps continuously instead of suspending. Turn
2502 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2503 T400CDT. This is off by default since most machines do fine without
2504 this feature.
2505
2506config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002507 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002508 bool "Make CPU Idle calls when idle"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002509 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002510 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2511 On some machines, this can activate improved power savings, such as
2512 a slowed CPU clock rate, when the machine is idle. These idle calls
2513 are made after the idle loop has run for some length of time (e.g.,
2514 333 mS). On some machines, this will cause a hang at boot time or
2515 whenever the CPU becomes idle. (On machines with more than one CPU,
2516 this option does nothing.)
2517
2518config APM_DISPLAY_BLANK
2519 bool "Enable console blanking using APM"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002520 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002521 Enable console blanking using the APM. Some laptops can use this to
2522 turn off the LCD backlight when the screen blanker of the Linux
2523 virtual console blanks the screen. Note that this is only used by
2524 the virtual console screen blanker, and won't turn off the backlight
2525 when using the X Window system. This also doesn't have anything to
2526 do with your VESA-compliant power-saving monitor. Further, this
2527 option doesn't work for all laptops -- it might not turn off your
2528 backlight at all, or it might print a lot of errors to the console,
2529 especially if you are using gpm.
2530
2531config APM_ALLOW_INTS
2532 bool "Allow interrupts during APM BIOS calls"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002533 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002534 Normally we disable external interrupts while we are making calls to
2535 the APM BIOS as a measure to lessen the effects of a badly behaving
2536 BIOS implementation. The BIOS should reenable interrupts if it
2537 needs to. Unfortunately, some BIOSes do not -- especially those in
2538 many of the newer IBM Thinkpads. If you experience hangs when you
2539 suspend, try setting this to Y. Otherwise, say N.
2540
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002541endif # APM
2542
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002543source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002544
2545source "drivers/cpuidle/Kconfig"
2546
Andy Henroid27471fd2008-10-09 11:45:22 -07002547source "drivers/idle/Kconfig"
2548
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002549endmenu
2550
2551
2552menu "Bus options (PCI etc.)"
2553
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002554choice
2555 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002556 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002557 default PCI_GOANY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002558 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002559 On PCI systems, the BIOS can be used to detect the PCI devices and
2560 determine their configuration. However, some old PCI motherboards
2561 have BIOS bugs and may crash if this is done. Also, some embedded
2562 PCI-based systems don't have any BIOS at all. Linux can also try to
2563 detect the PCI hardware directly without using the BIOS.
2564
2565 With this option, you can specify how Linux should detect the
2566 PCI devices. If you choose "BIOS", the BIOS will be used,
2567 if you choose "Direct", the BIOS won't be used, and if you
2568 choose "MMConfig", then PCI Express MMCONFIG will be used.
2569 If you choose "Any", the kernel will try MMCONFIG, then the
2570 direct access method and falls back to the BIOS if that doesn't
2571 work. If unsure, go with the default, which is "Any".
2572
2573config PCI_GOBIOS
2574 bool "BIOS"
2575
2576config PCI_GOMMCONFIG
2577 bool "MMConfig"
2578
2579config PCI_GODIRECT
2580 bool "Direct"
2581
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002582config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002583 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002584 depends on OLPC
2585
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002586config PCI_GOANY
2587 bool "Any"
2588
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002589endchoice
2590
2591config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002592 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002593 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002594
2595# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2596config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002597 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002598 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002599
2600config PCI_MMCONFIG
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002601 bool "Support mmconfig PCI config space access" if X86_64
2602 default y
Andy Shevchenko4590d982021-02-11 15:40:02 +02002603 depends on PCI && (ACPI || JAILHOUSE_GUEST)
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002604 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002605
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002606config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002607 def_bool y
2608 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002609
Alex Nixonb5401a92010-03-18 16:31:34 -04002610config PCI_XEN
2611 def_bool y
2612 depends on PCI && XEN
2613 select SWIOTLB_XEN
2614
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002615config MMCONF_FAM10H
2616 def_bool y
2617 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002618
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002619config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002620 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002621 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002622 help
2623 Read the PCI windows out of the CNB20LE host bridge. This allows
2624 PCI hotplug to work on systems with the CNB20LE chipset which do
2625 not have ACPI.
2626
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002627 There's no public spec for this chipset, and this functionality
2628 is known to be incomplete.
2629
2630 You should say N unless you know you need this.
2631
William Breathitt Gray3a495512016-05-27 18:08:27 -04002632config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002633 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002634 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002635 Expose ISA bus device drivers and options available for selection and
2636 configuration. Enable this option if your target machine has an ISA
2637 bus. ISA is an older system, displaced by PCI and newer bus
2638 architectures -- if your target machine is modern, it probably does
2639 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002640
2641 If unsure, say N.
2642
David Rientjes1c00f012011-03-22 16:34:59 -07002643# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002644config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002645 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2646 default y
2647 help
2648 Enables ISA-style DMA support for devices requiring such controllers.
2649 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002650
Linus Torvalds51e68d02016-05-21 10:25:19 -07002651if X86_32
2652
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002653config ISA
2654 bool "ISA support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002655 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002656 Find out whether you have ISA slots on your motherboard. ISA is the
2657 name of a bus system, i.e. the way the CPU talks to the other stuff
2658 inside your box. Other bus systems are PCI, EISA, MicroChannel
2659 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2660 newer boards don't support it. If you have ISA, say Y, otherwise N.
2661
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002662config SCx200
2663 tristate "NatSemi SCx200 support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002664 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002665 This provides basic support for National Semiconductor's
2666 (now AMD's) Geode processors. The driver probes for the
2667 PCI-IDs of several on-chip devices, so its a good dependency
2668 for other scx200_* drivers.
2669
2670 If compiled as a module, the driver is named scx200.
2671
2672config SCx200HR_TIMER
2673 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002674 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002675 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002676 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002677 This driver provides a clocksource built upon the on-chip
2678 27MHz high-resolution timer. Its also a workaround for
2679 NSC Geode SC-1100's buggy TSC, which loses time when the
2680 processor goes idle (as is done by the scheduler). The
2681 other workaround is idle=poll boot option.
2682
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002683config OLPC
2684 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002685 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002686 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002687 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002688 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002689 select IRQ_DOMAIN
Lubomir Rintel0c3d9312019-05-13 09:56:37 +02002690 select OLPC_EC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002691 help
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002692 Add support for detecting the unique features of the OLPC
2693 XO hardware.
2694
Daniel Drakea3128582011-06-25 17:34:10 +01002695config OLPC_XO1_PM
2696 bool "OLPC XO-1 Power Management"
Borislav Petkovfa112cf2018-10-05 15:13:07 +02002697 depends on OLPC && MFD_CS5535=y && PM_SLEEP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002698 help
Daniel Drake97c4cb72011-06-25 17:34:11 +01002699 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002700
Daniel Drakecfee9592011-06-25 17:34:17 +01002701config OLPC_XO1_RTC
2702 bool "OLPC XO-1 Real Time Clock"
2703 depends on OLPC_XO1_PM && RTC_DRV_CMOS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002704 help
Daniel Drakecfee9592011-06-25 17:34:17 +01002705 Add support for the XO-1 real time clock, which can be used as a
2706 programmable wakeup source.
2707
Daniel Drake7feda8e2011-06-25 17:34:12 +01002708config OLPC_XO1_SCI
2709 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002710 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002711 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002712 select POWER_SUPPLY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002713 help
Daniel Drake7feda8e2011-06-25 17:34:12 +01002714 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002715 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002716 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002717 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002718 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002719 - AC adapter status updates
2720 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002721
Daniel Drakea0f30f52011-06-25 17:34:18 +01002722config OLPC_XO15_SCI
2723 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002724 depends on OLPC && ACPI
2725 select POWER_SUPPLY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002726 help
Daniel Drakea0f30f52011-06-25 17:34:18 +01002727 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2728 - EC-driven system wakeups
2729 - AC adapter status updates
2730 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002731
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002732config ALIX
2733 bool "PCEngines ALIX System Support (LED setup)"
2734 select GPIOLIB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002735 help
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002736 This option enables system support for the PCEngines ALIX.
2737 At present this just sets up LEDs for GPIO control on
2738 ALIX2/3/6 boards. However, other system specific setup should
2739 get added here.
2740
2741 Note: You must still enable the drivers for GPIO and LED support
2742 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2743
2744 Note: You have to set alix.force=1 for boards with Award BIOS.
2745
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002746config NET5501
2747 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2748 select GPIOLIB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002749 help
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002750 This option enables system support for the Soekris Engineering net5501.
2751
Philip A. Prindeville31970592012-01-14 01:45:39 -07002752config GEOS
2753 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2754 select GPIOLIB
2755 depends on DMI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002756 help
Philip A. Prindeville31970592012-01-14 01:45:39 -07002757 This option enables system support for the Traverse Technologies GEOS.
2758
Vivien Didelot7d029122013-01-04 16:18:14 -05002759config TS5500
2760 bool "Technologic Systems TS-5500 platform support"
2761 depends on MELAN
2762 select CHECK_SIGNATURE
2763 select NEW_LEDS
2764 select LEDS_CLASS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002765 help
Vivien Didelot7d029122013-01-04 16:18:14 -05002766 This option enables system support for the Technologic Systems TS-5500.
2767
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002768endif # X86_32
2769
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002770config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002771 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002772 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002773
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002774endmenu
2775
2776
Christoph Hellwig15724972018-07-31 13:39:30 +02002777menu "Binary Emulations"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002778
2779config IA32_EMULATION
2780 bool "IA32 Emulation"
2781 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002782 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002783 select BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002784 select COMPAT_OLD_SIGACTION
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002785 help
H. J. Lu5fd92e62012-02-19 10:40:03 -08002786 Include code to run legacy 32-bit programs under a
2787 64-bit kernel. You should likely turn this on, unless you're
2788 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002789
2790config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002791 tristate "IA32 a.out support"
2792 depends on IA32_EMULATION
Borislav Petkoveac61652019-03-05 15:47:51 +01002793 depends on BROKEN
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002794 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002795 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002796
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002797config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002798 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002799 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002800 help
H. J. Lu5fd92e62012-02-19 10:40:03 -08002801 Include code to run binaries for the x32 native 32-bit ABI
2802 for 64-bit processors. An x32 process gets access to the
2803 full 64-bit register file and wide data path while leaving
2804 pointers at 32 bits for smaller memory footprint.
2805
2806 You will need a recent binutils (2.22 or later) with
2807 elf32_x86_64 support enabled to compile a kernel with this
2808 option set.
2809
Ingo Molnar953fee12016-11-15 10:22:52 +01002810config COMPAT_32
2811 def_bool y
2812 depends on IA32_EMULATION || X86_32
2813 select HAVE_UID16
2814 select OLD_SIGSUSPEND3
2815
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002816config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002817 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002818 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002819
Jan Beulich3120e252012-09-10 12:41:45 +01002820if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002821config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002822 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002823
2824config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002825 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002826 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002827endif
David Howellsee009e4a02011-03-07 15:06:20 +00002828
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002829endmenu
2830
2831
Keith Packarde5beae12008-11-03 18:21:45 +01002832config HAVE_ATOMIC_IOMAP
2833 def_bool y
2834 depends on X86_32
2835
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002836source "drivers/firmware/Kconfig"
2837
Avi Kivityedf88412007-12-16 11:02:48 +02002838source "arch/x86/kvm/Kconfig"
Jason A. Donenfeld5e8ebd82020-03-26 17:00:58 +09002839
2840source "arch/x86/Kconfig.assembler"