blob: 171faee05035b0054bd01059868643ebc45acb5d [file] [log] [blame]
Greg Kroah-Hartmanb2441312017-11-01 15:07:57 +01001# SPDX-License-Identifier: GPL-2.0
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01002# Select 32 or 64 bit
3config 64BIT
Masahiro Yamada104daea2018-05-28 18:21:40 +09004 bool "64-bit kernel" if "$(ARCH)" = "x86"
5 default "$(ARCH)" != "i386"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09006 help
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01007 Say yes to build a 64-bit kernel - formerly known as x86_64
8 Say no to build a 32-bit kernel - formerly known as i386
9
10config X86_32
Jan Beulich3120e252012-09-10 12:41:45 +010011 def_bool y
12 depends on !64BIT
Ingo Molnar341c7872016-11-15 10:04:55 +010013 # Options that are inherently 32-bit kernel only:
14 select ARCH_WANT_IPC_PARSE_VERSION
15 select CLKSRC_I8253
16 select CLONE_BACKWARDS
Thomas Gleixner157e1182020-11-03 10:27:20 +010017 select GENERIC_VDSO_32
Thomas Gleixner117ed452019-04-14 18:00:08 +020018 select HAVE_DEBUG_STACKOVERFLOW
Thomas Gleixner157e1182020-11-03 10:27:20 +010019 select KMAP_LOCAL
Ingo Molnar341c7872016-11-15 10:04:55 +010020 select MODULES_USE_ELF_REL
21 select OLD_SIGACTION
Brian Gerst2ca408d2020-11-30 17:30:59 -050022 select ARCH_SPLIT_ARG64
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +010023
24config X86_64
Jan Beulich3120e252012-09-10 12:41:45 +010025 def_bool y
26 depends on 64BIT
Ingo Molnard94e0682016-11-15 10:11:57 +010027 # Options that are inherently 64-bit kernel only:
Alexandre Ghiti4eb07162019-05-13 17:19:04 -070028 select ARCH_HAS_GIGANTIC_PAGE
Ard Biesheuvelc12d3362019-11-08 13:22:27 +010029 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
Ingo Molnard94e0682016-11-15 10:11:57 +010030 select ARCH_USE_CMPXCHG_LOCKREF
31 select HAVE_ARCH_SOFT_DIRTY
32 select MODULES_USE_ELF_RELA
Christoph Hellwigf616ab52018-05-09 06:53:49 +020033 select NEED_DMA_MAP_STATE
Christoph Hellwig09230cb2018-04-24 09:00:54 +020034 select SWIOTLB
Al Viro7facdc42020-06-13 23:03:25 -040035 select ARCH_HAS_ELFCORE_COMPAT
Kefeng Wang63703f32021-06-30 18:52:20 -070036 select ZONE_DMA32
Sam Ravnborg1032c0b2007-11-06 21:35:08 +010037
Steven Rostedt (VMware)518049d2019-05-10 12:05:46 -040038config FORCE_DYNAMIC_FTRACE
39 def_bool y
40 depends on X86_32
41 depends on FUNCTION_TRACER
42 select DYNAMIC_FTRACE
43 help
44 We keep the static function tracing (!DYNAMIC_FTRACE) around
45 in order to test the non static function tracing in the
46 generic code, as other architectures still use it. But we
47 only need to keep it around for x86_64. No need to keep it
48 for x86_32. For x86_32, force DYNAMIC_FTRACE.
Ingo Molnard94e0682016-11-15 10:11:57 +010049#
50# Arch settings
51#
52# ( Note that options that are marked 'if X86_64' could in principle be
53# ported to 32-bit as well. )
54#
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +010055config X86
Harvey Harrison3c2362e2008-01-30 13:31:03 +010056 def_bool y
Ingo Molnarc763ea22016-11-15 10:26:39 +010057 #
58 # Note: keep this list sorted alphabetically
59 #
Ingo Molnar6471b822015-06-03 10:00:13 +020060 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
61 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
Yury Norov942fa982018-05-16 11:18:49 +030062 select ARCH_32BIT_OFF_T if X86_32
Thomas Gleixner2a21ad52018-09-17 14:45:35 +020063 select ARCH_CLOCKSOURCE_INIT
Anshuman Khandual1e866972021-05-04 18:38:21 -070064 select ARCH_ENABLE_HUGEPAGE_MIGRATION if X86_64 && HUGETLB_PAGE && MIGRATION
Anshuman Khandual91024b32021-05-04 18:38:17 -070065 select ARCH_ENABLE_MEMORY_HOTPLUG if X86_64 || (X86_32 && HIGHMEM)
66 select ARCH_ENABLE_MEMORY_HOTREMOVE if MEMORY_HOTPLUG
Anshuman Khandualcebc7742021-06-30 18:51:58 -070067 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if (PGTABLE_LEVELS > 2) && (X86_64 || X86_PAE)
Anshuman Khandual1e866972021-05-04 18:38:21 -070068 select ARCH_ENABLE_THP_MIGRATION if X86_64 && TRANSPARENT_HUGEPAGE
Ingo Molnarc763ea22016-11-15 10:26:39 +010069 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
Anshuman Khandualc2280be2021-05-04 18:38:09 -070070 select ARCH_HAS_CACHE_LINE_SIZE
Laura Abbottfa5b6ec2017-01-10 13:35:40 -080071 select ARCH_HAS_DEBUG_VIRTUAL
Anshuman Khandual399145f2020-06-04 16:47:15 -070072 select ARCH_HAS_DEBUG_VM_PGTABLE if !X86_PAE
Dan Williams21266be2015-11-19 18:19:29 -080073 select ARCH_HAS_DEVMEM_IS_ALLOWED
Douglas Andersonb1a57bb2020-05-07 13:08:42 -070074 select ARCH_HAS_EARLY_DEBUG if KGDB
Ingo Molnar6471b822015-06-03 10:00:13 +020075 select ARCH_HAS_ELF_RANDOMIZE
Linus Torvalds72d93102014-09-13 11:14:53 -070076 select ARCH_HAS_FAST_MULTIPLIER
Dave Hansen316d0972018-04-20 15:20:28 -070077 select ARCH_HAS_FILTER_PGPROT
Daniel Micay6974f0c2017-07-12 14:36:10 -070078 select ARCH_HAS_FORTIFY_SOURCE
Riku Voipio957e3fa2014-12-12 16:57:44 -080079 select ARCH_HAS_GCOV_PROFILE_ALL
Peter Zijlstra0f1441b2020-06-12 16:05:26 +020080 select ARCH_HAS_KCOV if X86_64 && STACK_VALIDATION
Thiago Jung Bauermann0c9c1d52019-08-06 01:49:14 -030081 select ARCH_HAS_MEM_ENCRYPT
Mathieu Desnoyers10bcc802018-01-29 15:20:18 -050082 select ARCH_HAS_MEMBARRIER_SYNC_CORE
Daniel Borkmann0ebeea82020-05-15 12:11:16 +020083 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
Ingo Molnarc763ea22016-11-15 10:26:39 +010084 select ARCH_HAS_PMEM_API if X86_64
Robin Murphy17596732019-07-16 16:30:47 -070085 select ARCH_HAS_PTE_DEVMAP if X86_64
Laurent Dufour3010a5e2018-06-07 17:06:08 -070086 select ARCH_HAS_PTE_SPECIAL
Dan Williams0aed55a2017-05-29 12:22:50 -070087 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Dan Williamsec6347b2020-10-05 20:40:16 -070088 select ARCH_HAS_COPY_MC if X86_64
Daniel Borkmannd2852a22017-02-21 16:09:33 +010089 select ARCH_HAS_SET_MEMORY
Rick Edgecombed253ca02019-04-25 17:11:34 -070090 select ARCH_HAS_SET_DIRECT_MAP
Laura Abbottad21fc42017-02-06 16:31:57 -080091 select ARCH_HAS_STRICT_KERNEL_RWX
92 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050093 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Brian Gerst25c619e2020-03-13 15:51:42 -040094 select ARCH_HAS_SYSCALL_WRAPPER
Andrey Ryabininc6d30852016-01-20 15:00:55 -080095 select ARCH_HAS_UBSAN_SANITIZE_ALL
Zong Li7e01ccb2020-06-03 16:03:58 -070096 select ARCH_HAS_DEBUG_WX
Kefeng Wang63703f32021-06-30 18:52:20 -070097 select ARCH_HAS_ZONE_DMA_SET if EXPERT
Ingo Molnar6471b822015-06-03 10:00:13 +020098 select ARCH_HAVE_NMI_SAFE_CMPXCHG
99 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -0400100 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -0800101 select ARCH_MIGHT_HAVE_PC_SERIO
Thomas Gleixner3599fe12019-04-25 11:45:22 +0200102 select ARCH_STACKWALK
Arnd Bergmann2c870e62018-07-24 11:48:45 +0200103 select ARCH_SUPPORTS_ACPI
Ingo Molnar6471b822015-06-03 10:00:13 +0200104 select ARCH_SUPPORTS_ATOMIC_RMW
Mike Rapoport5d6ad662020-12-14 19:10:30 -0800105 select ARCH_SUPPORTS_DEBUG_PAGEALLOC
Ingo Molnar6471b822015-06-03 10:00:13 +0200106 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
Thomas Gleixner14df3262020-11-18 20:48:41 +0100107 select ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP if NR_CPUS <= 4096
Nathan Chancellor583bfd42021-04-29 16:26:12 -0700108 select ARCH_SUPPORTS_LTO_CLANG
109 select ARCH_SUPPORTS_LTO_CLANG_THIN
Ingo Molnar6471b822015-06-03 10:00:13 +0200110 select ARCH_USE_BUILTIN_BSWAP
Anshuman Khandualdce44562021-04-29 22:55:15 -0700111 select ARCH_USE_MEMTEST
Ingo Molnar6471b822015-06-03 10:00:13 +0200112 select ARCH_USE_QUEUED_RWLOCKS
113 select ARCH_USE_QUEUED_SPINLOCKS
Mark Brown2ce0d7f2020-04-16 19:24:02 +0100114 select ARCH_USE_SYM_ANNOTATIONS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -0700115 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Daniel Borkmann81c22042019-12-09 16:08:03 +0100116 select ARCH_WANT_DEFAULT_BPF_JIT if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100117 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Nick Desaulniers51c2ee62021-06-21 16:18:22 -0700118 select ARCH_WANTS_NO_INSTR
Alexandre Ghiti3876d4a2019-06-27 15:00:11 -0700119 select ARCH_WANT_HUGE_PMD_SHARE
Nathan Chancellor59612b22020-11-19 13:46:56 -0700120 select ARCH_WANT_LD_ORPHAN_WARN
Huang Ying38d8b4e2017-07-06 15:37:18 -0700121 select ARCH_WANTS_THP_SWAP if X86_64
Shile Zhang10916702019-12-04 08:46:31 +0800122 select BUILDTIME_TABLE_SORT
Ingo Molnar6471b822015-06-03 10:00:13 +0200123 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +0200124 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
125 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +0200126 select DCACHE_WORD_ACCESS
Linus Torvalds45471cd2015-06-24 19:52:06 -0700127 select EDAC_ATOMIC_SCRUB
128 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +0200129 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
130 select GENERIC_CLOCKEVENTS_MIN_ADJUST
131 select GENERIC_CMOS_UPDATE
132 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +0100133 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +0200134 select GENERIC_EARLY_IOREMAP
Thomas Gleixner27d6b4d2020-07-23 00:00:04 +0200135 select GENERIC_ENTRY
Ingo Molnar6471b822015-06-03 10:00:13 +0200136 select GENERIC_FIND_FIRST_BIT
137 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +0200138 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +0200139 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +0200140 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200141 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200142 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200143 select GENERIC_IRQ_SHOW
144 select GENERIC_PENDING_IRQ if SMP
Steven Price2ae27132020-02-03 17:36:24 -0800145 select GENERIC_PTDUMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200146 select GENERIC_SMP_IDLE_THREAD
147 select GENERIC_STRNCPY_FROM_USER
148 select GENERIC_STRNLEN_USER
149 select GENERIC_TIME_VSYSCALL
Vincenzo Frascino7ac87072019-06-21 10:52:49 +0100150 select GENERIC_GETTIMEOFDAY
Dmitry Safonov550a77a2019-11-12 01:27:11 +0000151 select GENERIC_VDSO_TIME_NS
Christoph Hellwig39656e82019-07-11 20:56:49 -0700152 select GUP_GET_PTE_LOW_HIGH if X86_PAE
Hans de Goede17e58882020-01-23 22:02:42 +0100153 select HARDIRQS_SW_RESEND
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200154 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200155 select HAVE_ACPI_APEI if ACPI
156 select HAVE_ACPI_APEI_NMI if ACPI
157 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200158 select HAVE_ARCH_AUDITSYSCALL
159 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
160 select HAVE_ARCH_JUMP_LABEL
Ard Biesheuvelb34006c2018-09-18 23:51:41 -0700161 select HAVE_ARCH_JUMP_LABEL_RELATIVE
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800162 select HAVE_ARCH_KASAN if X86_64
Daniel Axtens0609ae02019-11-30 17:55:00 -0800163 select HAVE_ARCH_KASAN_VMALLOC if X86_64
Alexander Potapenko1dc0da62021-02-25 17:18:57 -0800164 select HAVE_ARCH_KFENCE
Ingo Molnar6471b822015-06-03 10:00:13 +0200165 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800166 select HAVE_ARCH_MMAP_RND_BITS if MMU
167 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300168 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ard Biesheuvel271ca782018-08-21 21:56:00 -0700169 select HAVE_ARCH_PREL32_RELOCATIONS
Ingo Molnar6471b822015-06-03 10:00:13 +0200170 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700171 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Alexander Popovafaef012018-08-17 01:16:58 +0300172 select HAVE_ARCH_STACKLEAK
Ingo Molnar6471b822015-06-03 10:00:13 +0200173 select HAVE_ARCH_TRACEHOOK
174 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Matthew Wilcoxa00cc7d2017-02-24 14:57:02 -0800175 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
Peter Xub64d8d12020-04-20 18:13:45 -0700176 select HAVE_ARCH_USERFAULTFD_WP if X86_64 && USERFAULTFD
Axel Rasmussen7677f7f2021-05-04 18:35:36 -0700177 select HAVE_ARCH_USERFAULTFD_MINOR if X86_64 && USERFAULTFD
Andy Lutomirskie37e43a2016-08-11 02:35:23 -0700178 select HAVE_ARCH_VMAP_STACK if X86_64
Kees Cookfe950f62021-04-01 16:23:45 -0700179 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
Ingo Molnarc763ea22016-11-15 10:26:39 +0100180 select HAVE_ARCH_WITHIN_STACK_FRAMES
Masahiro Yamada2ff2b7e2019-08-19 14:54:20 +0900181 select HAVE_ASM_MODVERSIONS
Ingo Molnar6471b822015-06-03 10:00:13 +0200182 select HAVE_CMPXCHG_DOUBLE
183 select HAVE_CMPXCHG_LOCAL
184 select HAVE_CONTEXT_TRACKING if X86_64
Frederic Weisbeckerd1f250e2020-11-17 16:16:37 +0100185 select HAVE_CONTEXT_TRACKING_OFFSTACK if HAVE_CONTEXT_TRACKING
Ingo Molnar6471b822015-06-03 10:00:13 +0200186 select HAVE_C_RECORDMCOUNT
Sami Tolvanen6dafca92020-08-06 15:15:02 -0700187 select HAVE_OBJTOOL_MCOUNT if STACK_VALIDATION
Ingo Molnar6471b822015-06-03 10:00:13 +0200188 select HAVE_DEBUG_KMEMLEAK
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700189 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400190 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900191 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Steven Rostedt (VMware)02a474c2020-10-27 10:55:55 -0400192 select HAVE_DYNAMIC_FTRACE_WITH_ARGS if X86_64
Steven Rostedt (VMware)562955f2019-11-08 13:11:39 -0500193 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
Wang YanQing03f57812018-05-03 14:10:43 +0800194 select HAVE_EBPF_JIT
Johannes Berg58340a02008-07-25 01:45:33 -0700195 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Christoph Hellwig6630a8e2018-11-15 20:05:37 +0100196 select HAVE_EISA
Jiri Slaby5f56a5d2016-05-20 17:00:16 -0700197 select HAVE_EXIT_THREAD
Christoph Hellwig67a929e2019-07-11 20:57:14 -0700198 select HAVE_FAST_GUP
Steven Rostedt (VMware)644e0e82017-03-23 10:33:52 -0400199 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
Ingo Molnar6471b822015-06-03 10:00:13 +0200200 select HAVE_FTRACE_MCOUNT_RECORD
Ingo Molnar6471b822015-06-03 10:00:13 +0200201 select HAVE_FUNCTION_GRAPH_TRACER
202 select HAVE_FUNCTION_TRACER
Emese Revfy6b90bd42016-05-24 00:09:38 +0200203 select HAVE_GCC_PLUGINS
K.Prasad0067f122009-06-01 23:43:57 +0530204 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200205 select HAVE_IDE
206 select HAVE_IOREMAP_PROT
Thomas Gleixner624db9e2021-02-10 00:40:51 +0100207 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200208 select HAVE_IRQ_TIME_ACCOUNTING
209 select HAVE_KERNEL_BZIP2
210 select HAVE_KERNEL_GZIP
211 select HAVE_KERNEL_LZ4
212 select HAVE_KERNEL_LZMA
213 select HAVE_KERNEL_LZO
214 select HAVE_KERNEL_XZ
Nick Terrellfb46d052020-07-30 12:08:39 -0700215 select HAVE_KERNEL_ZSTD
Ingo Molnar6471b822015-06-03 10:00:13 +0200216 select HAVE_KPROBES
217 select HAVE_KPROBES_ON_FTRACE
Masami Hiramatsu540adea2018-01-13 02:55:03 +0900218 select HAVE_FUNCTION_ERROR_INJECTION
Ingo Molnar6471b822015-06-03 10:00:13 +0200219 select HAVE_KRETPROBES
220 select HAVE_KVM
221 select HAVE_LIVEPATCH if X86_64
Frederic Weisbecker01027522010-04-11 18:55:56 +0200222 select HAVE_MIXED_BREAKPOINTS_REGS
Josh Poimboeufee9f8fc2017-07-24 18:36:57 -0500223 select HAVE_MOD_ARCH_SPECIFIC
Joel Fernandes (Google)9f132f72019-01-03 15:28:41 -0800224 select HAVE_MOVE_PMD
Kalesh Singhbe37c982020-12-14 19:07:40 -0800225 select HAVE_MOVE_PUD
Petr Mladek42a0bb32016-05-20 17:00:33 -0700226 select HAVE_NMI
Ingo Molnar6471b822015-06-03 10:00:13 +0200227 select HAVE_OPTPROBES
228 select HAVE_PCSPKR_PLATFORM
229 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200230 select HAVE_PERF_EVENTS_NMI
Nicholas Piggin92e5aae2017-08-18 15:15:51 -0700231 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
Christoph Hellwigeb01d422018-11-15 20:05:32 +0100232 select HAVE_PCI
Jiri Olsac5e63192012-08-07 15:20:36 +0200233 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200234 select HAVE_PERF_USER_STACK_DUMP
Peter Zijlstraff2e6d722020-02-03 17:37:02 -0800235 select MMU_GATHER_RCU_TABLE_FREE if PARAVIRT
Thomas Gleixner00998082020-07-30 12:14:07 +0200236 select HAVE_POSIX_CPU_TIMERS_TASK_WORK
Ingo Molnar6471b822015-06-03 10:00:13 +0200237 select HAVE_REGS_AND_STACK_ACCESS_API
Jiri Slaby6415b382018-05-18 08:47:13 +0200238 select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION
Masami Hiramatsu3c88ee194c2018-04-25 21:20:57 +0900239 select HAVE_FUNCTION_ARG_ACCESS_API
Thomas Gleixnercd1a41c2021-02-10 00:40:52 +0100240 select HAVE_SOFTIRQ_ON_OWN_STACK
Masahiro Yamadad148eac2018-06-14 19:36:45 +0900241 select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
Ingo Molnarc763ea22016-11-15 10:26:39 +0100242 select HAVE_STACK_VALIDATION if X86_64
Josh Poimboeufe6d6c072020-08-18 15:57:44 +0200243 select HAVE_STATIC_CALL
Josh Poimboeuf1e7e4782020-08-18 15:57:45 +0200244 select HAVE_STATIC_CALL_INLINE if HAVE_STACK_VALIDATION
Michal Hocko6ef869e2021-01-18 15:12:19 +0100245 select HAVE_PREEMPT_DYNAMIC
Mathieu Desnoyersd6761b82018-06-02 08:43:58 -0400246 select HAVE_RSEQ
Ingo Molnar6471b822015-06-03 10:00:13 +0200247 select HAVE_SYSCALL_TRACEPOINTS
Ingo Molnar6471b822015-06-03 10:00:13 +0200248 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300249 select HAVE_USER_RETURN_NOTIFIER
Vincenzo Frascino7ac87072019-06-21 10:52:49 +0100250 select HAVE_GENERIC_VDSO
Thomas Gleixner05736e42018-05-29 17:48:27 +0200251 select HOTPLUG_SMT if SMP
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100252 select IRQ_FORCED_THREADING
Christoph Hellwig86596f02018-04-05 09:44:52 +0200253 select NEED_SG_DMA_LENGTH
Christoph Hellwig2eac9c22018-11-15 20:05:33 +0100254 select PCI_DOMAINS if PCI
Sinan Kaya625210c2019-01-21 23:19:58 +0000255 select PCI_LOCKLESS_CONFIG if PCI
Ingo Molnar6471b822015-06-03 10:00:13 +0200256 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500257 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200258 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200259 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500260 select SRCU
Josh Poimboeuf1e7e4782020-08-18 15:57:45 +0200261 select STACK_VALIDATION if HAVE_STACK_VALIDATION && (HAVE_STATIC_CALL_INLINE || RETPOLINE)
Ingo Molnar6471b822015-06-03 10:00:13 +0200262 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700263 select THREAD_INFO_IN_TASK
Masahiro Yamada4aae6832021-07-31 14:22:32 +0900264 select TRACE_IRQFLAGS_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +0200265 select USER_STACKTRACE_SUPPORT
266 select VIRT_TO_BUS
Ingo Molnar3b02a052020-04-13 09:44:39 +0200267 select HAVE_ARCH_KCSAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200268 select X86_FEATURE_NAMES if PROC_FS
Aubrey Li0c608da2019-06-06 09:22:35 +0800269 select PROC_PID_ARCH_STATUS if PROC_FS
Nayna Jain9e2b4be2020-03-08 20:57:51 -0400270 imply IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI
Balbir Singh7d8330a2008-02-10 12:46:28 +0530271
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200272config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100273 def_bool y
274 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200275
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700276config OUTPUT_FORMAT
277 string
278 default "elf32-i386" if X86_32
279 default "elf64-x86-64" if X86_64
280
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100281config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100282 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100283
284config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100285 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100286
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100287config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100288 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100289
Daniel Cashman9e08f572016-01-14 15:20:06 -0800290config ARCH_MMAP_RND_BITS_MIN
291 default 28 if 64BIT
292 default 8
293
294config ARCH_MMAP_RND_BITS_MAX
295 default 32 if 64BIT
296 default 16
297
298config ARCH_MMAP_RND_COMPAT_BITS_MIN
299 default 8
300
301config ARCH_MMAP_RND_COMPAT_BITS_MAX
302 default 16
303
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100304config SBUS
305 bool
306
307config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100308 def_bool y
309 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100310
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100311config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100312 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100313 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000314 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
315
316config GENERIC_BUG_RELATIVE_POINTERS
317 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100318
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100319config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100320 def_bool y
321 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100322
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100323config GENERIC_CALIBRATE_DELAY
324 def_bool y
325
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800326config ARCH_HAS_CPU_RELAX
327 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100328
Dave Hansen316d0972018-04-20 15:20:28 -0700329config ARCH_HAS_FILTER_PGPROT
330 def_bool y
331
Mike Travisdd5af902008-01-30 13:33:32 +0100332config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900333 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100334
Tejun Heo08fc4582009-08-14 15:00:49 +0900335config NEED_PER_CPU_EMBED_FIRST_CHUNK
336 def_bool y
337
338config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900339 def_bool y
340
Johannes Berg801e4062007-12-08 02:12:39 +0100341config ARCH_HIBERNATION_POSSIBLE
342 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100343
Johannes Bergf4cb5702007-12-08 02:14:00 +0100344config ARCH_SUSPEND_POSSIBLE
345 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100346
Steve Capper53313b22013-04-30 08:03:42 +0100347config ARCH_WANT_GENERAL_HUGETLB
348 def_bool y
349
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100350config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000351 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100352
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300353config KASAN_SHADOW_OFFSET
354 hex
355 depends on KASAN
356 default 0xdffffc0000000000
357
Shane Wang69575d32009-09-01 18:25:07 -0700358config HAVE_INTEL_TXT
359 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700360 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700361
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100362config X86_32_SMP
363 def_bool y
364 depends on X86_32 && SMP
365
366config X86_64_SMP
367 def_bool y
368 depends on X86_64 && SMP
369
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530370config ARCH_SUPPORTS_UPROBES
371 def_bool y
372
Rob Herringd20642f2014-04-18 17:19:54 -0500373config FIX_EARLYCON_MEM
374 def_bool y
375
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +0300376config DYNAMIC_PHYSICAL_MASK
377 bool
378
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700379config PGTABLE_LEVELS
380 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300381 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700382 default 4 if X86_64
383 default 3 if X86_PAE
384 default 2
385
Masahiro Yamada2a61f472018-05-28 18:22:00 +0900386config CC_HAS_SANE_STACKPROTECTOR
387 bool
388 default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
389 default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
390 help
391 We have to make sure stack protector is unconditionally disabled if
Andy Lutomirski3fb0fdb2021-02-13 11:19:44 -0800392 the compiler produces broken code or if it does not let us control
393 the segment on 32-bit kernels.
Masahiro Yamada2a61f472018-05-28 18:22:00 +0900394
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100395menu "Processor type and features"
396
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100397config SMP
398 bool "Symmetric multi-processing support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900399 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100400 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800401 a system with only one CPU, say N. If you have a system with more
402 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100403
Robert Graffham4a474152014-01-23 15:55:29 -0800404 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100405 machines, but will use only one CPU of a multiprocessor machine. If
406 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800407 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100408 will run faster if you say N here.
409
410 Note that if you say Y here and choose architecture "586" or
411 "Pentium" under "Processor family", the kernel will not work on 486
412 architectures. Similarly, multiprocessor kernels for the "PPro"
413 architecture may not work on all Pentium based boards.
414
415 People using multiprocessor machines who say Y here should also say
416 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
417 Management" code will be disabled if you say Y here.
418
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -0300419 See also <file:Documentation/x86/i386/IO-APIC.rst>,
Mauro Carvalho Chehab4f4cfa62019-06-27 14:56:51 -0300420 <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100421 <http://www.tldp.org/docs.html#howto>.
422
423 If you don't know what to do here, say N.
424
Josh Triplett9def39be2013-10-30 08:09:45 -0700425config X86_FEATURE_NAMES
426 bool "Processor feature human-readable names" if EMBEDDED
427 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900428 help
Josh Triplett9def39be2013-10-30 08:09:45 -0700429 This option compiles in a table of x86 feature bits and corresponding
430 names. This is required to support /proc/cpuinfo and a few kernel
431 messages. You can disable this to save space, at the expense of
432 making those few kernel messages show numeric feature bits instead.
433
434 If in doubt, say Y.
435
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800436config X86_X2APIC
437 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200438 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900439 help
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800440 This enables x2apic support on CPUs that have this feature.
441
442 This allows 32-bit apic IDs (so it can support very large systems),
443 and accesses the local apic via MSRs not via mmio.
444
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800445 If you don't know what to do here, say N.
446
Yinghai Lu6695c852008-06-19 12:13:09 -0700447config X86_MPPARSE
Andy Shevchenko4590d982021-02-11 15:40:02 +0200448 bool "Enable MPS table" if ACPI
Jan Beulich7a527682008-10-30 10:38:24 +0000449 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200450 depends on X86_LOCAL_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900451 help
Yinghai Lu6695c852008-06-19 12:13:09 -0700452 For old smp systems that do not have proper acpi support. Newer systems
453 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700454
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000455config GOLDFISH
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +0100456 def_bool y
457 depends on X86_GOLDFISH
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000458
David Woodhouse76b04382018-01-11 21:46:25 +0000459config RETPOLINE
460 bool "Avoid speculative indirect branches in kernel"
461 default y
462 help
463 Compile kernel with the retpoline compiler options to guard against
464 kernel-to-user data leaks by avoiding speculative indirect
465 branches. Requires a compiler with -mindirect-branch=thunk-extern
466 support for full protection. The kernel may run slower.
467
Johannes Weinere6d42932019-01-29 17:44:36 -0500468config X86_CPU_RESCTRL
469 bool "x86 CPU resource control support"
Babu Moger6fe07ce2018-11-21 20:28:39 +0000470 depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100471 select KERNFS
Chen Yue79f15a2020-01-15 17:28:51 +0800472 select PROC_CPU_RESCTRL if PROC_FS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700473 help
Johannes Weinere6d42932019-01-29 17:44:36 -0500474 Enable x86 CPU resource control support.
Babu Moger6fe07ce2018-11-21 20:28:39 +0000475
476 Provide support for the allocation and monitoring of system resources
477 usage by the CPU.
478
479 Intel calls this Intel Resource Director Technology
480 (Intel(R) RDT). More information about RDT can be found in the
481 Intel x86 Architecture Software Developer Manual.
482
483 AMD calls this AMD Platform Quality of Service (AMD QoS).
484 More information about AMD QoS can be found in the AMD64 Technology
485 Platform Quality of Service Extensions manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700486
487 Say N if unsure.
488
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800489if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800490config X86_BIGSMP
491 bool "Support for big SMP systems with more than 8 CPUs"
492 depends on SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900493 help
Randy Dunlape133f6e2019-12-03 16:06:47 -0800494 This option is needed for the systems that have more than 8 CPUs.
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800495
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800496config X86_EXTENDED_PLATFORM
497 bool "Support for extended (non-PC) x86 platforms"
498 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900499 help
Ingo Molnar06ac8342009-01-27 18:11:43 +0100500 If you disable this option then the kernel will only support
501 standard PC platforms. (which covers the vast majority of
502 systems out there.)
503
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800504 If you enable this option then you'll be able to select support
505 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100506 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800507 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800508 RDC R-321x SoC
509 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200510 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200511 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100512
513 If you have one of these systems, or if you want to build a
514 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800515endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100516
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800517if X86_64
518config X86_EXTENDED_PLATFORM
519 bool "Support for extended (non-PC) x86 platforms"
520 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900521 help
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800522 If you disable this option then the kernel will only support
523 standard PC platforms. (which covers the vast majority of
524 systems out there.)
525
526 If you enable this option then you'll be able to select support
527 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800528 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800529 ScaleMP vSMP
530 SGI Ultraviolet
531
532 If you have one of these systems, or if you want to build a
533 generic distribution kernel, say Y here - otherwise say N.
534endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800535# This is an alphabetically sorted list of 64 bit extended platforms
536# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800537config X86_NUMACHIP
538 bool "Numascale NumaChip"
539 depends on X86_64
540 depends on X86_EXTENDED_PLATFORM
541 depends on NUMA
542 depends on SMP
543 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700544 depends on PCI_MMCONFIG
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900545 help
Steffen Persvold44b111b52011-12-06 00:07:26 +0800546 Adds support for Numascale NumaChip large-SMP systems. Needed to
547 enable more than ~168 cores.
548 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100549
Ingo Molnar6a485652009-01-27 18:29:13 +0100550config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800551 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100552 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100553 select PARAVIRT
554 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800555 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300556 depends on SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900557 help
Ingo Molnar6a485652009-01-27 18:29:13 +0100558 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
559 supposed to run on these EM64T-based machines. Only choose this option
560 if you have one of these machines.
561
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800562config X86_UV
563 bool "SGI Ultraviolet"
564 depends on X86_64
565 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500566 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800567 depends on EFI
Ingo Molnarc2209ea2021-04-20 09:47:42 +0200568 depends on KEXEC_CORE
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700569 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200570 depends on PCI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900571 help
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800572 This option is needed in order to support SGI Ultraviolet systems.
573 If you don't have one of these, you should say N here.
574
575# Following is an alphabetically sorted list of 32 bit extended platforms
576# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100577
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000578config X86_GOLDFISH
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +0100579 bool "Goldfish (Virtual Platform)"
580 depends on X86_EXTENDED_PLATFORM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900581 help
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000582 Enable support for the Goldfish virtual platform used primarily
583 for Android development. Unless you are building for the Android
584 Goldfish emulator say N here.
585
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800586config X86_INTEL_CE
587 bool "CE4100 TV platform"
588 depends on PCI
589 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800590 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800591 depends on X86_32
592 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800593 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100594 select OF
595 select OF_EARLY_FLATTREE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900596 help
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800597 Select for the Intel CE media processor (CE4100) SOC.
598 This option compiles in support for the CE4100 SOC for settop
599 boxes and media devices.
600
David Cohen4cb9b002013-12-16 17:37:26 -0800601config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100602 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100603 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800604 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000605 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200606 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000607 depends on X86_IO_APIC
David Cohen4cb9b002013-12-16 17:37:26 -0800608 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000609 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000610 select APB_TIMER
Mika Westerberg54b34aa2020-04-16 11:15:33 +0300611 select INTEL_SCU_PCI
Mika Westerberg15a713d2012-01-26 17:35:05 +0000612 select MFD_INTEL_MSIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900613 help
David Cohen4cb9b002013-12-16 17:37:26 -0800614 Select to build a kernel capable of supporting Intel MID (Mobile
615 Internet Device) platform systems which do not have the PCI legacy
616 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000617
David Cohen4cb9b002013-12-16 17:37:26 -0800618 Intel MID platforms are based on an Intel processor and chipset which
619 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100620
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000621config X86_INTEL_QUARK
622 bool "Intel Quark platform support"
623 depends on X86_32
624 depends on X86_EXTENDED_PLATFORM
625 depends on X86_PLATFORM_DEVICES
626 depends on X86_TSC
627 depends on PCI
628 depends on PCI_GOANY
629 depends on X86_IO_APIC
630 select IOSF_MBI
631 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200632 select COMMON_CLK
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900633 help
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000634 Select to include support for Quark X1000 SoC.
635 Say Y here if you have a Quark based system such as the Arduino
636 compatible Intel Galileo.
637
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000638config X86_INTEL_LPSS
639 bool "Intel Low Power Subsystem Support"
Sinan Kaya5962dd22019-01-02 18:10:37 +0000640 depends on X86 && ACPI && PCI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000641 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300642 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100643 select IOSF_MBI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900644 help
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000645 Select to build support for Intel Low Power Subsystem such as
646 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300647 things like clock tree (common clock framework) and pincontrol
648 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000649
Ken Xue92082a82015-02-06 08:27:51 +0800650config X86_AMD_PLATFORM_DEVICE
651 bool "AMD ACPI2Platform devices support"
652 depends on ACPI
653 select COMMON_CLK
654 select PINCTRL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900655 help
Ken Xue92082a82015-02-06 08:27:51 +0800656 Select to interpret AMD specific ACPI device to platform device
657 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
658 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
659 implemented under PINCTRL subsystem.
660
David E. Boxced3ce72014-09-17 22:13:50 -0700661config IOSF_MBI
662 tristate "Intel SoC IOSF Sideband support for SoC platforms"
663 depends on PCI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900664 help
David E. Boxced3ce72014-09-17 22:13:50 -0700665 This option enables sideband register access support for Intel SoC
666 platforms. On these platforms the IOSF sideband is used in lieu of
667 MSR's for some register accesses, mostly but not limited to thermal
668 and power. Drivers may query the availability of this device to
669 determine if they need the sideband in order to work on these
670 platforms. The sideband is available on the following SoC products.
671 This list is not meant to be exclusive.
672 - BayTrail
673 - Braswell
674 - Quark
675
676 You should say Y if you are running a kernel on one of these SoC's.
677
David E. Boxed2226b2014-09-17 22:13:51 -0700678config IOSF_MBI_DEBUG
679 bool "Enable IOSF sideband access through debugfs"
680 depends on IOSF_MBI && DEBUG_FS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900681 help
David E. Boxed2226b2014-09-17 22:13:51 -0700682 Select this option to expose the IOSF sideband access registers (MCR,
683 MDR, MCRX) through debugfs to write and read register information from
684 different units on the SoC. This is most useful for obtaining device
685 state information for debug and analysis. As this is a general access
686 mechanism, users of this option would have specific knowledge of the
687 device they want to access.
688
689 If you don't require the option or are in doubt, say N.
690
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800691config X86_RDC321X
692 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100693 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800694 depends on X86_EXTENDED_PLATFORM
695 select M486
696 select X86_REBOOTFIXUPS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900697 help
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800698 This option is needed for RDC R-321x system-on-chip, also known
699 as R-8610-(G).
700 If you don't have one of these chips, you should say N here.
701
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100702config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100703 bool "Support non-standard 32-bit SMP architectures"
704 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800705 depends on X86_EXTENDED_PLATFORM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900706 help
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800707 This option compiles in the bigsmp and STA2X11 default
708 subarchitectures. It is intended for a generic binary
709 kernel. If you select them all, kernel will probe it one by
710 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700711
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800712# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700713
Linus Torvaldsd949f362009-09-26 09:35:07 -0700714config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100715 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700716 # MCE code calls memory_failure():
717 depends on X86_MCE
718 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700719 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
720 depends on X86_64 || !SPARSEMEM
721 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700722
Alessandro Rubini83125a32012-04-04 19:40:21 +0200723config STA2X11
724 bool "STA2X11 Companion Chip Support"
725 depends on X86_32_NON_STANDARD && PCI
Alessandro Rubini83125a32012-04-04 19:40:21 +0200726 select SWIOTLB
727 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200728 select GPIOLIB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900729 help
Alessandro Rubini83125a32012-04-04 19:40:21 +0200730 This adds support for boards based on the STA2X11 IO-Hub,
731 a.k.a. "ConneXt". The chip is used in place of the standard
732 PC chipset, so all "standard" peripherals are missing. If this
733 option is selected the kernel will still be able to boot on
734 standard PC machines.
735
Shérab82148d12010-09-25 06:06:57 +0200736config X86_32_IRIS
737 tristate "Eurobraille/Iris poweroff module"
738 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900739 help
Shérab82148d12010-09-25 06:06:57 +0200740 The Iris machines from EuroBraille do not have APM or ACPI support
741 to shut themselves down properly. A special I/O sequence is
742 needed to do so, which is what this module does at
743 kernel shutdown.
744
745 This is only for Iris machines from EuroBraille.
746
747 If unused, say N.
748
Ingo Molnarae1e9132008-11-11 09:05:16 +0100749config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100750 def_bool y
751 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800752 depends on X86
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900753 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100754 Calculate simpler /proc/<PID>/wchan values. If this option
755 is disabled then wchan values will recurse back to the
756 caller function. This provides more accurate wchan values,
757 at the expense of slightly more scheduling overhead.
758
759 If in doubt, say "Y".
760
Borislav Petkov6276a072013-03-04 21:20:21 +0100761menuconfig HYPERVISOR_GUEST
762 bool "Linux guest support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900763 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100764 Say Y here to enable options for running Linux under various hyper-
765 visors. This option enables basic hypervisor detection and platform
766 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100767
Borislav Petkov6276a072013-03-04 21:20:21 +0100768 If you say N, all options in this submenu will be skipped and
769 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100770
Borislav Petkov6276a072013-03-04 21:20:21 +0100771if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100772
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100773config PARAVIRT
774 bool "Enable paravirtualization code"
Juergen Grossa0e2bf72021-03-11 15:23:09 +0100775 depends on HAVE_STATIC_CALL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900776 help
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100777 This changes the kernel so it can modify itself when it is run
778 under a hypervisor, potentially improving performance significantly
779 over full virtualization. However, when run without a hypervisor
780 the kernel is theoretically slower and slightly larger.
781
Juergen Grossc00a2802018-08-28 09:40:21 +0200782config PARAVIRT_XXL
783 bool
784
Borislav Petkov6276a072013-03-04 21:20:21 +0100785config PARAVIRT_DEBUG
786 bool "paravirt-ops debugging"
787 depends on PARAVIRT && DEBUG_KERNEL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900788 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100789 Enable to debug paravirt_ops internals. Specifically, BUG if
790 a paravirt_op is missing when it is called.
791
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700792config PARAVIRT_SPINLOCKS
793 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700794 depends on PARAVIRT && SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900795 help
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700796 Paravirtualized spinlocks allow a pvops backend to replace the
797 spinlock implementation with something virtualization-friendly
798 (for example, block the virtual CPU rather than spinning).
799
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530800 It has a minimal impact on native kernels and gives a nice performance
801 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700802
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530803 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700804
Zhao Yakuiecca25022019-04-30 11:45:23 +0800805config X86_HV_CALLBACK_VECTOR
806 def_bool n
807
Borislav Petkov6276a072013-03-04 21:20:21 +0100808source "arch/x86/xen/Kconfig"
809
810config KVM_GUEST
811 bool "KVM Guest support (including kvmclock)"
812 depends on PARAVIRT
813 select PARAVIRT_CLOCK
Marcelo Tosattia1c44232019-07-03 20:51:29 -0300814 select ARCH_CPUIDLE_HALTPOLL
Vitaly Kuznetsovb1d40572020-05-25 16:41:23 +0200815 select X86_HV_CALLBACK_VECTOR
Borislav Petkov6276a072013-03-04 21:20:21 +0100816 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900817 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100818 This option enables various optimizations for running under the KVM
819 hypervisor. It includes a paravirtualized clock, so that instead
820 of relying on a PIT (or probably other) emulation by the
821 underlying device model, the host provides the guest with
822 timing infrastructure such as time of day, and system time
823
Marcelo Tosattia1c44232019-07-03 20:51:29 -0300824config ARCH_CPUIDLE_HALTPOLL
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +0100825 def_bool n
826 prompt "Disable host haltpoll when loading haltpoll driver"
827 help
Marcelo Tosattia1c44232019-07-03 20:51:29 -0300828 If virtualized under KVM, disable host haltpoll.
829
Maran Wilson77336072018-12-10 11:07:28 -0800830config PVH
831 bool "Support for running PVH guests"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900832 help
Maran Wilson77336072018-12-10 11:07:28 -0800833 This option enables the PVH entry point for guest virtual machines
834 as specified in the x86/HVM direct boot ABI.
835
Borislav Petkov6276a072013-03-04 21:20:21 +0100836config PARAVIRT_TIME_ACCOUNTING
837 bool "Paravirtual steal time accounting"
838 depends on PARAVIRT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900839 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100840 Select this option to enable fine granularity task steal time
841 accounting. Time spent executing other tasks in parallel with
842 the current vCPU is discounted from the vCPU power. To account for
843 that, there can be a small performance impact.
844
845 If in doubt, say N here.
846
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200847config PARAVIRT_CLOCK
848 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200849
Jan Kiszka4a362602017-11-27 09:11:46 +0100850config JAILHOUSE_GUEST
851 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100852 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100853 select X86_PM_TIMER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900854 help
Jan Kiszka4a362602017-11-27 09:11:46 +0100855 This option allows to run Linux as guest in a Jailhouse non-root
856 cell. You can leave this option disabled if you only want to start
857 Jailhouse and run Linux afterwards in the root cell.
858
Zhao Yakuiec7972c2019-04-30 11:45:24 +0800859config ACRN_GUEST
860 bool "ACRN Guest support"
861 depends on X86_64
Zhao Yakui498ad392019-04-30 11:45:25 +0800862 select X86_HV_CALLBACK_VECTOR
Zhao Yakuiec7972c2019-04-30 11:45:24 +0800863 help
864 This option allows to run Linux as guest in the ACRN hypervisor. ACRN is
865 a flexible, lightweight reference open-source hypervisor, built with
866 real-time and safety-criticality in mind. It is built for embedded
867 IOT with small footprint and real-time features. More details can be
868 found in https://projectacrn.org/.
869
Borislav Petkov6276a072013-03-04 21:20:21 +0100870endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400871
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100872source "arch/x86/Kconfig.cpu"
873
874config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100875 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100876 prompt "HPET Timer Support" if X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900877 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100878 Use the IA-PC HPET (High Precision Event Timer) to manage
879 time in preference to the PIT and RTC, if a HPET is
880 present.
881 HPET is the next generation timer replacing legacy 8254s.
882 The HPET provides a stable time base on SMP
883 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200884 as it is off-chip. The interface used is documented
885 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100886
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100887 You can safely choose Y here. However, HPET will only be
888 activated if the platform and the BIOS support this feature.
889 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100890
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100891 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100892
893config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100894 def_bool y
Anand K Mistry3228e1d2021-02-04 18:32:32 +1100895 depends on HPET_TIMER && (RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100896
David Rientjes6a108a12011-01-20 14:44:16 -0800897# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100898# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700899config DMI
900 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800901 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800902 bool "Enable DMI scanning" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900903 help
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700904 Enabled scanning of DMI to identify machine quirks. Say Y
905 here unless you have verified that your setup is not
906 affected by entries in the DMI blacklist. Required by PNP
907 BIOS code.
908
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100909config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700910 bool "Old AMD GART IOMMU support"
Christoph Hellwig2f9237d2020-07-08 09:30:00 +0200911 select DMA_OPS
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200912 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100913 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200914 depends on X86_64 && PCI && AMD_NB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900915 help
Ingo Molnarced3c422013-10-06 11:45:20 +0200916 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
917 GART based hardware IOMMUs.
918
919 The GART supports full DMA access for devices with 32-bit access
920 limitations, on systems with more than 3 GB. This is usually needed
921 for USB, sound, many IDE/SATA chipsets and some other devices.
922
923 Newer systems typically have a modern AMD IOMMU, supported via
924 the CONFIG_AMD_IOMMU=y config option.
925
926 In normal configurations this driver is only active when needed:
927 there's more than 3 GB of memory and the system contains a
928 32-bit limited device.
929
930 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100931
Mike Travis1184dc22008-05-12 21:21:12 +0200932config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200933 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700934 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800935 select CPUMASK_OFFSTACK
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900936 help
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200937 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200938 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100939
Ingo Molnaraec64872018-02-10 12:36:29 +0100940#
941# The maximum number of CPUs supported:
942#
943# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
944# and which can be configured interactively in the
945# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
946#
947# The ranges are different on 32-bit and 64-bit kernels, depending on
948# hardware capabilities and scalability features of the kernel.
949#
950# ( If MAXSMP is enabled we just use the highest possible value and disable
951# interactive configuration. )
952#
953
954config NR_CPUS_RANGE_BEGIN
955 int
956 default NR_CPUS_RANGE_END if MAXSMP
957 default 1 if !SMP
958 default 2
959
960config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800961 int
962 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100963 default 64 if SMP && X86_BIGSMP
964 default 8 if SMP && !X86_BIGSMP
965 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800966
Ingo Molnaraec64872018-02-10 12:36:29 +0100967config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800968 int
969 depends on X86_64
Scott Wood1edae1a2019-10-12 02:00:54 -0500970 default 8192 if SMP && CPUMASK_OFFSTACK
971 default 512 if SMP && !CPUMASK_OFFSTACK
Ingo Molnaraec64872018-02-10 12:36:29 +0100972 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800973
Ingo Molnaraec64872018-02-10 12:36:29 +0100974config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800975 int
976 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100977 default 32 if X86_BIGSMP
978 default 8 if SMP
979 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800980
Ingo Molnaraec64872018-02-10 12:36:29 +0100981config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800982 int
983 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100984 default 8192 if MAXSMP
985 default 64 if SMP
986 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800987
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100988config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800989 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +0100990 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
991 default NR_CPUS_DEFAULT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900992 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100993 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500994 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +0300995 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100996 minimum value which makes sense is 2.
997
Ingo Molnaraec64872018-02-10 12:36:29 +0100998 This is purely to save memory: each supported CPU adds about 8KB
999 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001000
1001config SCHED_SMT
Thomas Gleixnerdbe73362018-11-25 19:33:37 +01001002 def_bool y if SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001003
1004config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001005 def_bool y
1006 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001007 depends on SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001008 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001009 Multi-core scheduler support improves the CPU scheduler's decision
1010 making when dealing with multi-core CPU chips at a cost of slightly
1011 increased overhead in some places. If unsure say N here.
1012
Tim Chende966cf2016-11-29 10:43:27 -08001013config SCHED_MC_PRIO
1014 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001015 depends on SCHED_MC && CPU_SUP_INTEL
1016 select X86_INTEL_PSTATE
1017 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001018 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001019 help
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001020 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1021 core ordering determined at manufacturing time, which allows
1022 certain cores to reach higher turbo frequencies (when running
1023 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001024
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001025 Enabling this kernel feature teaches the scheduler about
1026 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1027 scheduler's CPU selection logic accordingly, so that higher
1028 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001029
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001030 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001031
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001032 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001033
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001034config UP_LATE_INIT
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001035 def_bool y
1036 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001037
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001038config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001039 bool "Local APIC support on uniprocessors" if !PCI_MSI
1040 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001041 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001042 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001043 A local APIC (Advanced Programmable Interrupt Controller) is an
1044 integrated interrupt controller in the CPU. If you have a single-CPU
1045 system which has a processor with a local APIC, you can say Y here to
1046 enable and use it. If you say Y here even though your machine doesn't
1047 have a local APIC, then the kernel will still run with no slowdown at
1048 all. The local APIC supports CPU-generated self-interrupts (timer,
1049 performance counters), and the NMI watchdog which detects hard
1050 lockups.
1051
1052config X86_UP_IOAPIC
1053 bool "IO-APIC support on uniprocessors"
1054 depends on X86_UP_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001055 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001056 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1057 SMP-capable replacement for PC-style interrupt controllers. Most
1058 SMP systems and many recent uniprocessor systems have one.
1059
1060 If you have a single-CPU system with an IO-APIC, you can say Y here
1061 to use it. If you say Y here even though your machine doesn't have
1062 an IO-APIC, then the kernel will still run with no slowdown at all.
1063
1064config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001065 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001066 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001067 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001068 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001069
1070config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001071 def_bool y
1072 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001073
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001074config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1075 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001076 depends on X86_IO_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001077 help
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001078 This option enables a workaround that fixes a source of
1079 spurious interrupts. This is recommended when threaded
1080 interrupt handling is used on systems where the generation of
1081 superfluous "boot interrupts" cannot be disabled.
1082
1083 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1084 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1085 kernel does during interrupt handling). On chipsets where this
1086 boot IRQ generation cannot be disabled, this workaround keeps
1087 the original IRQ line masked so that only the equivalent "boot
1088 IRQ" is delivered to the CPUs. The workaround also tells the
1089 kernel to set up the IRQ handler on the boot IRQ line. In this
1090 way only one interrupt is delivered to the kernel. Otherwise
1091 the spurious second interrupt may cause the kernel to bring
1092 down (vital) interrupt lines.
1093
1094 Only affects "broken" chipsets. Interrupt sharing may be
1095 increased on these systems.
1096
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001097config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001098 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001099 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001100 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001101 help
Andi Kleenbab9bc62009-07-09 00:31:38 +02001102 Machine Check support allows the processor to notify the
1103 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001104 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001105 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001106
Tony Luck5de97c92017-03-27 11:33:03 +02001107config X86_MCELOG_LEGACY
1108 bool "Support for deprecated /dev/mcelog character device"
1109 depends on X86_MCE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001110 help
Tony Luck5de97c92017-03-27 11:33:03 +02001111 Enable support for /dev/mcelog which is needed by the old mcelog
1112 userspace logging daemon. Consider switching to the new generation
1113 rasdaemon solution.
1114
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001115config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001116 def_bool y
1117 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001118 depends on X86_MCE && X86_LOCAL_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001119 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001120 Additional support for intel specific MCE features such as
1121 the thermal monitor.
1122
1123config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001124 def_bool y
1125 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001126 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001127 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001128 Additional support for AMD specific MCE features such as
1129 the DRAM Error Threshold.
1130
Andi Kleen4efc0672009-04-28 19:07:31 +02001131config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001132 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001133 depends on X86_32 && X86_MCE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001134 help
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001135 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001136 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001137 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001138
Andi Kleenb2762682009-02-12 13:49:31 +01001139config X86_MCE_THRESHOLD
1140 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001141 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001142
Andi Kleenea149b32009-04-29 19:31:00 +02001143config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001144 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001145 tristate "Machine check injector support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001146 help
Andi Kleenea149b32009-04-29 19:31:00 +02001147 Provide support for injecting machine checks for testing purposes.
1148 If you don't know what a machine check is and you don't do kernel
1149 QA it is safe to say n.
1150
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001151source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001152
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001153config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001154 bool "Legacy VM86 support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001155 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001156 help
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001157 This option allows user programs to put the CPU into V8086
1158 mode, which is an 80286-era approximation of 16-bit real mode.
1159
1160 Some very old versions of X and/or vbetool require this option
1161 for user mode setting. Similarly, DOSEMU will use it if
1162 available to accelerate real mode DOS programs. However, any
1163 recent version of DOSEMU, X, or vbetool should be fully
1164 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001165 fall back to software emulation. Nevertheless, if you are using
1166 a 16-bit DOS program where 16-bit performance matters, vm86
1167 mode might be faster than emulation and you might want to
1168 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001169
Ingo Molnar1e642812015-09-05 08:58:10 +02001170 Note that any app that works on a 64-bit kernel is unlikely to
1171 need this option, as 64-bit kernels don't, and can't, support
1172 V8086 mode. This option is also unrelated to 16-bit protected
1173 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001174
Ingo Molnar1e642812015-09-05 08:58:10 +02001175 Enabling this option increases the complexity of the kernel
1176 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001177
Ingo Molnar1e642812015-09-05 08:58:10 +02001178 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001179
1180config VM86
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001181 bool
1182 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001183
1184config X86_16BIT
1185 bool "Enable support for 16-bit segments" if EXPERT
1186 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001187 depends on MODIFY_LDT_SYSCALL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001188 help
H. Peter Anvin34273f42014-05-04 10:36:22 -07001189 This option is required by programs like Wine to run 16-bit
1190 protected mode legacy code on x86 processors. Disabling
1191 this option saves about 300 bytes on i386, or around 6K text
1192 plus 16K runtime memory on x86-64,
1193
1194config X86_ESPFIX32
1195 def_bool y
1196 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001197
H. Peter Anvin197725d2014-05-04 10:00:49 -07001198config X86_ESPFIX64
1199 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001200 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001201
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001202config X86_VSYSCALL_EMULATION
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001203 bool "Enable vsyscall emulation" if EXPERT
1204 default y
1205 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001206 help
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001207 This enables emulation of the legacy vsyscall page. Disabling
1208 it is roughly equivalent to booting with vsyscall=none, except
1209 that it will also disable the helpful warning if a program
1210 tries to use a vsyscall. With this option set to N, offending
1211 programs will just segfault, citing addresses of the form
1212 0xffffffffff600?00.
1213
1214 This option is required by many programs built before 2013, and
1215 care should be used even with newer programs if set to N.
1216
1217 Disabling this option saves about 7K of kernel size and
1218 possibly 4K of additional runtime pagetable memory.
1219
Thomas Gleixner111e7b12019-11-12 21:40:33 +01001220config X86_IOPL_IOPERM
1221 bool "IOPERM and IOPL Emulation"
Thomas Gleixnera24ca992019-11-11 23:03:29 +01001222 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001223 help
Thomas Gleixner111e7b12019-11-12 21:40:33 +01001224 This enables the ioperm() and iopl() syscalls which are necessary
1225 for legacy applications.
1226
Thomas Gleixnerc8137ac2019-11-11 23:03:28 +01001227 Legacy IOPL support is an overbroad mechanism which allows user
1228 space aside of accessing all 65536 I/O ports also to disable
1229 interrupts. To gain this access the caller needs CAP_SYS_RAWIO
1230 capabilities and permission from potentially active security
1231 modules.
1232
1233 The emulation restricts the functionality of the syscall to
1234 only allowing the full range I/O port access, but prevents the
Thomas Gleixnera24ca992019-11-11 23:03:29 +01001235 ability to disable interrupts from user space which would be
1236 granted if the hardware IOPL mechanism would be used.
Thomas Gleixnerc8137ac2019-11-11 23:03:28 +01001237
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001238config TOSHIBA
1239 tristate "Toshiba Laptop support"
1240 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001241 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001242 This adds a driver to safely access the System Management Mode of
1243 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1244 not work on models with a Phoenix BIOS. The System Management Mode
1245 is used to set the BIOS and power saving options on Toshiba portables.
1246
1247 For information on utilities to make use of this driver see the
1248 Toshiba Linux utilities web site at:
1249 <http://www.buzzard.org.uk/toshiba/>.
1250
1251 Say Y if you intend to run this kernel on a Toshiba portable.
1252 Say N otherwise.
1253
1254config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001255 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001256 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001257 select SENSORS_DELL_SMM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001258 help
Pali Rohár039ae582015-05-14 13:16:37 +02001259 This option enables legacy /proc/i8k userspace interface in hwmon
1260 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1261 temperature and allows controlling fan speeds of Dell laptops via
1262 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1263 it reports also power and hotkey status. For fan speed control is
1264 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001265
Pali Rohár039ae582015-05-14 13:16:37 +02001266 Say Y if you intend to run this kernel on old Dell laptops or want to
1267 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001268 Say N otherwise.
1269
1270config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001271 bool "Enable X86 board specific fixups for reboot"
1272 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001273 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001274 This enables chipset and/or board specific fixups to be done
1275 in order to get reboot to work correctly. This is only needed on
1276 some combinations of hardware and BIOS. The symptom, for which
1277 this config is intended, is when reboot ends with a stalled/hung
1278 system.
1279
1280 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001281 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001282
1283 Say Y if you want to enable the fixup. Currently, it's safe to
1284 enable this option even if you don't need it.
1285 Say N otherwise.
1286
1287config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001288 bool "CPU microcode loading support"
1289 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001290 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001291 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001292 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001293 Intel and AMD processors. The Intel support is for the IA32 family,
1294 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1295 AMD support is for families 0x10 and later. You will obviously need
1296 the actual microcode binary data itself which is not shipped with
1297 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001298
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001299 The preferred method to load microcode from a detached initrd is described
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001300 in Documentation/x86/microcode.rst. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001301 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1302 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001303
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001304 In addition, you can build the microcode into the kernel. For that you
1305 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1306 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001307
Peter Oruba8d86f392008-07-28 18:44:21 +02001308config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001309 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001310 depends on MICROCODE
1311 default MICROCODE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001312 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001313 This options enables microcode patch loading support for Intel
1314 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001315
Alanb8989db2014-01-20 18:01:56 +00001316 For the current Intel microcode data package go to
1317 <https://downloadcenter.intel.com> and search for
1318 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001319
Peter Oruba80cc9f12008-07-28 18:44:22 +02001320config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001321 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001322 depends on MICROCODE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001323 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001324 If you select this option, microcode patch loading support for AMD
1325 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001326
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001327config MICROCODE_OLD_INTERFACE
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001328 bool "Ancient loading interface (DEPRECATED)"
1329 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001330 depends on MICROCODE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001331 help
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001332 DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface
1333 which was used by userspace tools like iucode_tool and microcode.ctl.
1334 It is inadequate because it runs too late to be able to properly
1335 load microcode on a machine and it needs special tools. Instead, you
1336 should've switched to the early loading method with the initrd or
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001337 builtin microcode by now: Documentation/x86/microcode.rst
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001338
1339config X86_MSR
1340 tristate "/dev/cpu/*/msr - Model-specific register support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001341 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001342 This device gives privileged processes access to the x86
1343 Model-Specific Registers (MSRs). It is a character device with
1344 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1345 MSR accesses are directed to a specific CPU on multi-processor
1346 systems.
1347
1348config X86_CPUID
1349 tristate "/dev/cpu/*/cpuid - CPU information support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001350 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001351 This device gives processes access to the x86 CPUID instruction to
1352 be executed on a specific processor. It is a character device
1353 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1354 /dev/cpu/31/cpuid.
1355
1356choice
1357 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001358 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001359 depends on X86_32
1360
1361config NOHIGHMEM
1362 bool "off"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001363 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001364 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1365 However, the address space of 32-bit x86 processors is only 4
1366 Gigabytes large. That means that, if you have a large amount of
1367 physical memory, not all of it can be "permanently mapped" by the
1368 kernel. The physical memory that's not permanently mapped is called
1369 "high memory".
1370
1371 If you are compiling a kernel which will never run on a machine with
1372 more than 1 Gigabyte total physical RAM, answer "off" here (default
1373 choice and suitable for most users). This will result in a "3GB/1GB"
1374 split: 3GB are mapped so that each process sees a 3GB virtual memory
1375 space and the remaining part of the 4GB virtual memory space is used
1376 by the kernel to permanently map as much physical memory as
1377 possible.
1378
1379 If the machine has between 1 and 4 Gigabytes physical RAM, then
1380 answer "4GB" here.
1381
1382 If more than 4 Gigabytes is used then answer "64GB" here. This
1383 selection turns Intel PAE (Physical Address Extension) mode on.
1384 PAE implements 3-level paging on IA32 processors. PAE is fully
1385 supported by Linux, PAE mode is implemented on all recent Intel
1386 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1387 then the kernel will not boot on CPUs that don't support PAE!
1388
1389 The actual amount of total physical memory will either be
1390 auto detected or can be forced by using a kernel command line option
1391 such as "mem=256M". (Try "man bootparam" or see the documentation of
1392 your boot loader (lilo or loadlin) about how to pass options to the
1393 kernel at boot time.)
1394
1395 If unsure, say "off".
1396
1397config HIGHMEM4G
1398 bool "4GB"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001399 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001400 Select this if you have a 32-bit processor and between 1 and 4
1401 gigabytes of physical RAM.
1402
1403config HIGHMEM64G
1404 bool "64GB"
Maciej W. Rozycki0ef34392021-04-14 12:38:28 +02001405 depends on !M486SX && !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001406 select X86_PAE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001407 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001408 Select this if you have a 32-bit processor and more than 4
1409 gigabytes of physical RAM.
1410
1411endchoice
1412
1413choice
David Rientjes6a108a12011-01-20 14:44:16 -08001414 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001415 default VMSPLIT_3G
1416 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001417 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001418 Select the desired split between kernel and user memory.
1419
1420 If the address range available to the kernel is less than the
1421 physical memory installed, the remaining memory will be available
1422 as "high memory". Accessing high memory is a little more costly
1423 than low memory, as it needs to be mapped into the kernel first.
1424 Note that increasing the kernel address space limits the range
1425 available to user programs, making the address space there
1426 tighter. Selecting anything other than the default 3G/1G split
1427 will also likely make your kernel incompatible with binary-only
1428 kernel modules.
1429
1430 If you are not absolutely sure what you are doing, leave this
1431 option alone!
1432
1433 config VMSPLIT_3G
1434 bool "3G/1G user/kernel split"
1435 config VMSPLIT_3G_OPT
1436 depends on !X86_PAE
1437 bool "3G/1G user/kernel split (for full 1G low memory)"
1438 config VMSPLIT_2G
1439 bool "2G/2G user/kernel split"
1440 config VMSPLIT_2G_OPT
1441 depends on !X86_PAE
1442 bool "2G/2G user/kernel split (for full 2G low memory)"
1443 config VMSPLIT_1G
1444 bool "1G/3G user/kernel split"
1445endchoice
1446
1447config PAGE_OFFSET
1448 hex
1449 default 0xB0000000 if VMSPLIT_3G_OPT
1450 default 0x80000000 if VMSPLIT_2G
1451 default 0x78000000 if VMSPLIT_2G_OPT
1452 default 0x40000000 if VMSPLIT_1G
1453 default 0xC0000000
1454 depends on X86_32
1455
1456config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001457 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001458 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001459
1460config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001461 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001462 depends on X86_32 && !HIGHMEM4G
Christoph Hellwigd4a451d2018-04-03 16:24:20 +02001463 select PHYS_ADDR_T_64BIT
Christian Melki9d99c712015-10-05 17:31:33 +02001464 select SWIOTLB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001465 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001466 PAE is required for NX support, and furthermore enables
1467 larger swapspace support for non-overcommit purposes. It
1468 has the cost of more pagetable lookup overhead, and also
1469 consumes more pagetable space per process.
1470
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001471config X86_5LEVEL
1472 bool "Enable 5-level page tables support"
Kirill A. Shutemov18ec1ea2019-09-13 12:54:52 +03001473 default y
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001474 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001475 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001476 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001477 help
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001478 5-level paging enables access to larger address space:
1479 upto 128 PiB of virtual address space and 4 PiB of
1480 physical address space.
1481
1482 It will be supported by future Intel CPUs.
1483
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001484 A kernel with the option enabled can be booted on machines that
1485 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001486
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001487 See Documentation/x86/x86_64/5level-paging.rst for more
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001488 information.
1489
1490 Say N if unsure.
1491
Ingo Molnar10971ab2015-03-05 08:18:23 +01001492config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001493 def_bool y
Vlastimil Babka2e1da132019-08-07 15:02:58 +02001494 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001495 help
Ingo Molnar10971ab2015-03-05 08:18:23 +01001496 Certain kernel features effectively disable kernel
1497 linear 1 GB mappings (even if the CPU otherwise
1498 supports them), so don't confuse the user by printing
1499 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001500
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001501config X86_CPA_STATISTICS
1502 bool "Enable statistic for Change Page Attribute"
1503 depends on DEBUG_FS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001504 help
Ingo Molnarb75baaf2019-11-20 15:57:04 +01001505 Expose statistics about the Change Page Attribute mechanism, which
Colin Ian Kinga9432452019-04-16 11:57:51 +01001506 helps to determine the effectiveness of preserving large and huge
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001507 page mappings when mapping protections are changed.
1508
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001509config AMD_MEM_ENCRYPT
1510 bool "AMD Secure Memory Encryption (SME) support"
1511 depends on X86_64 && CPU_SUP_AMD
David Rientjes82fef0a2020-04-14 17:05:01 -07001512 select DMA_COHERENT_POOL
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +03001513 select DYNAMIC_PHYSICAL_MASK
Ard Biesheuvelce9084b2019-02-02 10:41:17 +01001514 select ARCH_USE_MEMREMAP_PROT
Tom Lendacky9087c372019-07-10 19:01:19 +00001515 select ARCH_HAS_FORCE_DMA_UNENCRYPTED
Joerg Roedel597cfe482020-09-07 15:15:24 +02001516 select INSTRUCTION_DECODER
Tom Lendacky22916412021-03-04 16:40:11 -06001517 select ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001518 help
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001519 Say yes to enable support for the encryption of system memory.
1520 This requires an AMD processor that supports Secure Memory
1521 Encryption (SME).
1522
1523config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1524 bool "Activate AMD Secure Memory Encryption (SME) by default"
1525 default y
1526 depends on AMD_MEM_ENCRYPT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001527 help
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001528 Say yes to have system memory encrypted by default if running on
1529 an AMD processor that supports Secure Memory Encryption (SME).
1530
1531 If set to Y, then the encryption of system memory can be
1532 deactivated with the mem_encrypt=off command line option.
1533
1534 If set to N, then the encryption of system memory can be
1535 activated with the mem_encrypt=on command line option.
1536
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001537# Common NUMA Features
1538config NUMA
Randy Dunlape133f6e2019-12-03 16:06:47 -08001539 bool "NUMA Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001540 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001541 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1542 default y if X86_BIGSMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001543 help
Randy Dunlape133f6e2019-12-03 16:06:47 -08001544 Enable NUMA (Non-Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001545
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001546 The kernel will try to allocate memory used by a CPU on the
1547 local memory controller of the CPU and add some more
1548 NUMA awareness to the kernel.
1549
Ingo Molnarc280ea52008-11-08 13:29:45 +01001550 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001551 (or later), AMD Opteron, or EM64T NUMA.
1552
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001553 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001554 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001555
1556 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001557
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001558config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001559 def_bool y
1560 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001561 depends on X86_64 && NUMA && PCI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001562 help
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001563 Enable AMD NUMA node topology detection. You should say Y here if
1564 you have a multi processor AMD system. This uses an old method to
1565 read the NUMA configuration directly from the builtin Northbridge
1566 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1567 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001568
1569config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001570 def_bool y
1571 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001572 depends on X86_64 && NUMA && ACPI && PCI
1573 select ACPI_NUMA
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001574 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001575 Enable ACPI SRAT based node topology detection.
1576
1577config NUMA_EMU
1578 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001579 depends on NUMA
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001580 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001581 Enable NUMA emulation. A flat machine will be split
1582 into virtual nodes when booted with "numa=fake=N", where N is the
1583 number of nodes. This is only useful for debugging.
1584
1585config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001586 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001587 range 1 10
1588 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001589 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001590 default "3"
Mike Rapoporta9ee6cf2021-06-28 19:43:01 -07001591 depends on NUMA
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001592 help
Mike Travis1184dc22008-05-12 21:21:12 +02001593 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001594 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001595
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001596config ARCH_FLATMEM_ENABLE
1597 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001598 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001599
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001600config ARCH_SPARSEMEM_ENABLE
1601 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001602 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001603 select SPARSEMEM_STATIC if X86_32
1604 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1605
Tejun Heo3b166512011-04-01 11:15:12 +02001606config ARCH_SPARSEMEM_DEFAULT
Mike Rapoport6ad57f72019-04-24 16:24:11 +03001607 def_bool X86_64 || (NUMA && X86_32)
Tejun Heo3b166512011-04-01 11:15:12 +02001608
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001609config ARCH_SELECT_MEMORY_MODEL
1610 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001611 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001612
1613config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001614 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001615 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001616 help
1617 This option enables a sysfs memory/probe interface for testing.
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001618 See Documentation/admin-guide/mm/memory-hotplug.rst for more information.
Toshi Kania0842b72013-07-19 11:47:48 -06001619 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001620
Tejun Heo3b166512011-04-01 11:15:12 +02001621config ARCH_PROC_KCORE_TEXT
1622 def_bool y
1623 depends on X86_64 && PROC_KCORE
1624
Avi Kivitya29815a2010-01-10 16:28:09 +02001625config ILLEGAL_POINTER_VALUE
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001626 hex
1627 default 0 if X86_32
1628 default 0xdead000000000000 if X86_64
Avi Kivitya29815a2010-01-10 16:28:09 +02001629
Dan Williams7a678322015-08-19 00:34:34 -04001630config X86_PMEM_LEGACY_DEVICE
1631 bool
1632
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001633config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001634 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001635 depends on PHYS_ADDR_T_64BIT
1636 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001637 select X86_PMEM_LEGACY_DEVICE
Dan Williams7b27a862020-02-16 12:01:16 -08001638 select NUMA_KEEP_MEMINFO if NUMA
Dan Williams9f53f9f2015-06-09 15:33:45 -04001639 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001640 help
1641 Treat memory marked using the non-standard e820 type of 12 as used
1642 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1643 The kernel will offer these regions to the 'pmem' driver so
1644 they can be used for persistent storage.
1645
1646 Say Y if unsure.
1647
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001648config HIGHPTE
1649 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001650 depends on HIGHMEM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001651 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001652 The VM uses one page table entry for each page of physical memory.
1653 For systems with a lot of RAM, this can be wasteful of precious
1654 low memory. Setting this option will put user-space page table
1655 entries in high memory.
1656
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001657config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001658 bool "Check for low memory corruption"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001659 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001660 Periodically check for memory corruption in low memory, which
1661 is suspected to be caused by BIOS. Even when enabled in the
1662 configuration, it is disabled at runtime. Enable it by
1663 setting "memory_corruption_check=1" on the kernel command
1664 line. By default it scans the low 64k of memory every 60
1665 seconds; see the memory_corruption_check_size and
1666 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001667 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001668
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001669 When enabled with the default parameters, this option has
1670 almost no overhead, as it reserves a relatively small amount
1671 of memory and scans it infrequently. It both detects corruption
1672 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001673
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001674 It is, however, intended as a diagnostic tool; if repeatable
1675 BIOS-originated corruption always affects the same memory,
1676 you can use memmap= to prevent the kernel from using that
1677 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001678
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001679config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001680 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001681 depends on X86_CHECK_BIOS_CORRUPTION
1682 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001683 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001684 Set whether the default state of memory_corruption_check is
1685 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001686
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001687config MATH_EMULATION
1688 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001689 depends on MODIFY_LDT_SYSCALL
Arnd Bergmann87d60212019-10-01 16:23:35 +02001690 prompt "Math emulation" if X86_32 && (M486SX || MELAN)
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001691 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001692 Linux can emulate a math coprocessor (used for floating point
1693 operations) if you don't have one. 486DX and Pentium processors have
1694 a math coprocessor built in, 486SX and 386 do not, unless you added
1695 a 487DX or 387, respectively. (The messages during boot time can
1696 give you some hints here ["man dmesg"].) Everyone needs either a
1697 coprocessor or this emulation.
1698
1699 If you don't have a math coprocessor, you need to say Y here; if you
1700 say Y here even though you have a coprocessor, the coprocessor will
1701 be used nevertheless. (This behavior can be changed with the kernel
1702 command line option "no387", which comes handy if your coprocessor
1703 is broken. Try "man bootparam" or see the documentation of your boot
1704 loader (lilo or loadlin) about how to pass options to the kernel at
1705 boot time.) This means that it is a good idea to say Y here if you
1706 intend to use this kernel on different machines.
1707
1708 More information about the internals of the Linux math coprocessor
1709 emulation can be found in <file:arch/x86/math-emu/README>.
1710
1711 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1712 kernel, it won't hurt.
1713
1714config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001715 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001716 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001717 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001718 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1719 the Memory Type Range Registers (MTRRs) may be used to control
1720 processor access to memory ranges. This is most useful if you have
1721 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1722 allows bus write transfers to be combined into a larger transfer
1723 before bursting over the PCI/AGP bus. This can increase performance
1724 of image write operations 2.5 times or more. Saying Y here creates a
1725 /proc/mtrr file which may be used to manipulate your processor's
1726 MTRRs. Typically the X server should use this.
1727
1728 This code has a reasonably generic interface so that similar
1729 control registers on other processors can be easily supported
1730 as well:
1731
1732 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1733 Registers (ARRs) which provide a similar functionality to MTRRs. For
1734 these, the ARRs are used to emulate the MTRRs.
1735 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1736 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1737 write-combining. All of these processors are supported by this code
1738 and it makes sense to say Y here if you have one of them.
1739
1740 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1741 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1742 can lead to all sorts of problems, so it's good to say Y here.
1743
1744 You can safely say Y even if your machine doesn't have MTRRs, you'll
1745 just add about 9 KB to your kernel.
1746
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001747 See <file:Documentation/x86/mtrr.rst> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001748
Yinghai Lu95ffa242008-04-29 03:52:33 -07001749config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001750 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001751 prompt "MTRR cleanup support"
1752 depends on MTRR
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001753 help
Thomas Gleixneraba37282008-07-15 14:48:48 +02001754 Convert MTRR layout from continuous to discrete, so X drivers can
1755 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001756
Thomas Gleixneraba37282008-07-15 14:48:48 +02001757 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001758 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001759 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001760
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001761 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001762
1763config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001764 int "MTRR cleanup enable value (0-1)"
1765 range 0 1
1766 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001767 depends on MTRR_SANITIZER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001768 help
Yinghai Luf5098d62008-04-29 20:25:58 -07001769 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001770
Yinghai Lu12031a62008-05-02 02:40:22 -07001771config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1772 int "MTRR cleanup spare reg num (0-7)"
1773 range 0 7
1774 default "1"
1775 depends on MTRR_SANITIZER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001776 help
Yinghai Lu12031a62008-05-02 02:40:22 -07001777 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001778 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001779
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001780config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001781 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001782 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001783 depends on MTRR
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001784 help
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001785 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001786
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001787 PATs are the modern equivalents of MTRRs and are much more
1788 flexible than MTRRs.
1789
1790 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001791 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001792
1793 If unsure, say Y.
1794
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001795config ARCH_USES_PG_UNCACHED
1796 def_bool y
1797 depends on X86_PAT
1798
H. Peter Anvin628c6242011-07-31 13:59:29 -07001799config ARCH_RANDOM
1800 def_bool y
1801 prompt "x86 architectural random number generator" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001802 help
H. Peter Anvin628c6242011-07-31 13:59:29 -07001803 Enable the x86 architectural RDRAND instruction
1804 (Intel Bull Mountain technology) to generate random numbers.
1805 If supported, this is a high bandwidth, cryptographically
1806 secure hardware random number generator.
1807
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001808config X86_SMAP
1809 def_bool y
1810 prompt "Supervisor Mode Access Prevention" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001811 help
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001812 Supervisor Mode Access Prevention (SMAP) is a security
1813 feature in newer Intel processors. There is a small
1814 performance cost if this enabled and turned on; there is
1815 also a small increase in the kernel size if this is enabled.
1816
1817 If unsure, say Y.
1818
Babu Mogerb9718802019-11-05 21:25:32 +00001819config X86_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001820 def_bool y
Babu Mogerb9718802019-11-05 21:25:32 +00001821 prompt "User Mode Instruction Prevention" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001822 help
Babu Mogerb9718802019-11-05 21:25:32 +00001823 User Mode Instruction Prevention (UMIP) is a security feature in
1824 some x86 processors. If enabled, a general protection fault is
1825 issued if the SGDT, SLDT, SIDT, SMSW or STR instructions are
1826 executed in user mode. These instructions unnecessarily expose
1827 information about the hardware state.
Ricardo Neri796ebc82017-11-13 22:29:42 -08001828
1829 The vast majority of applications do not use these instructions.
1830 For the very few that do, software emulation is provided in
1831 specific cases in protected and virtual-8086 modes. Emulated
1832 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001833
Dave Hansen35e97792016-02-12 13:02:00 -08001834config X86_INTEL_MEMORY_PROTECTION_KEYS
Babu Moger38f3e772020-05-28 11:08:23 -05001835 prompt "Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001836 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001837 # Note: only available in 64-bit mode
Babu Moger38f3e772020-05-28 11:08:23 -05001838 depends on X86_64 && (CPU_SUP_INTEL || CPU_SUP_AMD)
Ingo Molnar52c8e602016-11-15 10:15:03 +01001839 select ARCH_USES_HIGH_VMA_FLAGS
1840 select ARCH_HAS_PKEYS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001841 help
Dave Hansen284244a2016-02-12 13:02:28 -08001842 Memory Protection Keys provides a mechanism for enforcing
1843 page-based protections, but without requiring modification of the
1844 page tables when an application changes protection domains.
1845
Mauro Carvalho Chehab1eecbcd2019-06-07 15:54:31 -03001846 For details, see Documentation/core-api/protection-keys.rst
Dave Hansen284244a2016-02-12 13:02:28 -08001847
1848 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001849
Michal Hockodb616172019-10-23 12:35:50 +02001850choice
1851 prompt "TSX enable mode"
1852 depends on CPU_SUP_INTEL
1853 default X86_INTEL_TSX_MODE_OFF
1854 help
1855 Intel's TSX (Transactional Synchronization Extensions) feature
1856 allows to optimize locking protocols through lock elision which
1857 can lead to a noticeable performance boost.
1858
1859 On the other hand it has been shown that TSX can be exploited
1860 to form side channel attacks (e.g. TAA) and chances are there
1861 will be more of those attacks discovered in the future.
1862
1863 Therefore TSX is not enabled by default (aka tsx=off). An admin
1864 might override this decision by tsx=on the command line parameter.
1865 Even with TSX enabled, the kernel will attempt to enable the best
1866 possible TAA mitigation setting depending on the microcode available
1867 for the particular machine.
1868
1869 This option allows to set the default tsx mode between tsx=on, =off
1870 and =auto. See Documentation/admin-guide/kernel-parameters.txt for more
1871 details.
1872
1873 Say off if not sure, auto if TSX is in use but it should be used on safe
1874 platforms or on if TSX is in use and the security aspect of tsx is not
1875 relevant.
1876
1877config X86_INTEL_TSX_MODE_OFF
1878 bool "off"
1879 help
1880 TSX is disabled if possible - equals to tsx=off command line parameter.
1881
1882config X86_INTEL_TSX_MODE_ON
1883 bool "on"
1884 help
1885 TSX is always enabled on TSX capable HW - equals the tsx=on command
1886 line parameter.
1887
1888config X86_INTEL_TSX_MODE_AUTO
1889 bool "auto"
1890 help
1891 TSX is enabled on TSX capable HW that is believed to be safe against
1892 side channel attacks- equals the tsx=auto command line parameter.
1893endchoice
1894
Sean Christophersone7e05452020-11-13 00:01:16 +02001895config X86_SGX
1896 bool "Software Guard eXtensions (SGX)"
1897 depends on X86_64 && CPU_SUP_INTEL
1898 depends on CRYPTO=y
1899 depends on CRYPTO_SHA256=y
1900 select SRCU
1901 select MMU_NOTIFIER
Jarkko Sakkinen901ddbb2021-03-18 01:53:31 +02001902 select NUMA_KEEP_MEMINFO if NUMA
Sean Christophersone7e05452020-11-13 00:01:16 +02001903 help
1904 Intel(R) Software Guard eXtensions (SGX) is a set of CPU instructions
1905 that can be used by applications to set aside private regions of code
1906 and data, referred to as enclaves. An enclave's private memory can
1907 only be accessed by code running within the enclave. Accesses from
1908 outside the enclave, including other enclaves, are disallowed by
1909 hardware.
1910
1911 If unsure, say N.
1912
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001913config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001914 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001915 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001916 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001917 select EFI_RUNTIME_WRAPPERS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001918 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001919 This enables the kernel to use EFI runtime services that are
1920 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001921
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001922 This option is only useful on systems that have EFI firmware.
1923 In addition, you should use the latest ELILO loader available
1924 at <http://elilo.sourceforge.net> in order to take advantage
1925 of EFI runtime services. However, even with this option, the
1926 resultant kernel should continue to boot on existing non-EFI
1927 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001928
Matt Fleming291f3632011-12-12 21:27:52 +00001929config EFI_STUB
Ard Biesheuvel8f24f8c2019-12-24 16:10:12 +01001930 bool "EFI stub support"
1931 depends on EFI && !X86_USE_3DNOW
1932 depends on $(cc-option,-mabi=ms) || X86_32
1933 select RELOCATABLE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001934 help
Ard Biesheuvel8f24f8c2019-12-24 16:10:12 +01001935 This kernel feature allows a bzImage to be loaded directly
Matt Fleming291f3632011-12-12 21:27:52 +00001936 by EFI firmware without the use of a bootloader.
1937
Mauro Carvalho Chehab4f4cfa62019-06-27 14:56:51 -03001938 See Documentation/admin-guide/efi-stub.rst for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001939
Matt Fleming7d453ee2014-01-10 18:52:06 +00001940config EFI_MIXED
1941 bool "EFI mixed-mode support"
1942 depends on EFI_STUB && X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001943 help
Matt Fleming7d453ee2014-01-10 18:52:06 +00001944 Enabling this feature allows a 64-bit kernel to be booted
1945 on a 32-bit firmware, provided that your CPU supports 64-bit
1946 mode.
1947
1948 Note that it is not possible to boot a mixed-mode enabled
1949 kernel via the EFI boot stub - a bootloader that supports
1950 the EFI handover protocol must be used.
1951
1952 If unsure, say N.
1953
Masahiro Yamada8636a1f2018-12-11 20:01:04 +09001954source "kernel/Kconfig.hz"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001955
1956config KEXEC
1957 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001958 select KEXEC_CORE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001959 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001960 kexec is a system call that implements the ability to shutdown your
1961 current kernel, and to start another kernel. It is like a reboot
1962 but it is independent of the system firmware. And like a reboot
1963 you can start any kernel with it, not just Linux.
1964
1965 The name comes from the similarity to the exec system call.
1966
1967 It is an ongoing process to be certain the hardware in a machine
1968 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001969 initially work for you. As of this writing the exact hardware
1970 interface is strongly in flux, so no good recommendation can be
1971 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001972
Vivek Goyal74ca3172014-08-29 15:18:46 -07001973config KEXEC_FILE
1974 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07001975 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07001976 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07001977 depends on X86_64
1978 depends on CRYPTO=y
1979 depends on CRYPTO_SHA256=y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001980 help
Vivek Goyal74ca3172014-08-29 15:18:46 -07001981 This is new version of kexec system call. This system call is
1982 file based and takes file descriptors as system call argument
1983 for kernel and initramfs as opposed to list of segments as
1984 accepted by previous system call.
1985
AKASHI Takahirob799a092018-04-13 15:35:45 -07001986config ARCH_HAS_KEXEC_PURGATORY
1987 def_bool KEXEC_FILE
1988
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07001989config KEXEC_SIG
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001990 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07001991 depends on KEXEC_FILE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001992 help
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07001993
1994 This option makes the kexec_file_load() syscall check for a valid
1995 signature of the kernel image. The image can still be loaded without
1996 a valid signature unless you also enable KEXEC_SIG_FORCE, though if
1997 there's a signature that we can check, then it must be valid.
1998
1999 In addition to this option, you need to enable signature
2000 verification for the corresponding kernel image type being
2001 loaded in order for this to work.
2002
2003config KEXEC_SIG_FORCE
2004 bool "Require a valid signature in kexec_file_load() syscall"
2005 depends on KEXEC_SIG
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002006 help
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002007 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002008 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002009
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002010config KEXEC_BZIMAGE_VERIFY_SIG
2011 bool "Enable bzImage signature verification support"
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07002012 depends on KEXEC_SIG
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002013 depends on SIGNED_PE_FILE_VERIFICATION
2014 select SYSTEM_TRUSTED_KEYRING
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002015 help
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002016 Enable bzImage signature verification support.
2017
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002018config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002019 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002020 depends on X86_64 || (X86_32 && HIGHMEM)
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002021 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002022 Generate crash dump after being started by kexec.
2023 This should be normally only set in special crash dump kernels
2024 which are loaded in the main kernel with kexec-tools into
2025 a specially reserved region and then later executed after
2026 a crash by kdump/kexec. The crash dump kernel must be compiled
2027 to a memory address not used by the main kernel or BIOS using
2028 PHYSICAL_START, or it must be built as a relocatable image
2029 (CONFIG_RELOCATABLE=y).
Mauro Carvalho Chehab330d4812019-06-13 15:21:39 -03002030 For more details see Documentation/admin-guide/kdump/kdump.rst
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002031
Huang Ying3ab83522008-07-25 19:45:07 -07002032config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002033 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002034 depends on KEXEC && HIBERNATION
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002035 help
Huang Ying89081d12008-07-25 19:45:10 -07002036 Jump between original kernel and kexeced kernel and invoke
2037 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002038
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002039config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002040 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002041 default "0x1000000"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002042 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002043 This gives the physical address where the kernel is loaded.
2044
2045 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2046 bzImage will decompress itself to above physical address and
2047 run from there. Otherwise, bzImage will run from the address where
2048 it has been loaded by the boot loader and will ignore above physical
2049 address.
2050
2051 In normal kdump cases one does not have to set/change this option
2052 as now bzImage can be compiled as a completely relocatable image
2053 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2054 address. This option is mainly useful for the folks who don't want
2055 to use a bzImage for capturing the crash dump and want to use a
2056 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2057 to be specifically compiled to run from a specific memory area
2058 (normally a reserved region) and this option comes handy.
2059
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002060 So if you are using bzImage for capturing the crash dump,
2061 leave the value here unchanged to 0x1000000 and set
2062 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2063 for capturing the crash dump change this value to start of
2064 the reserved region. In other words, it can be set based on
2065 the "X" value as specified in the "crashkernel=YM@XM"
2066 command line boot parameter passed to the panic-ed
Mauro Carvalho Chehab330d4812019-06-13 15:21:39 -03002067 kernel. Please take a look at Documentation/admin-guide/kdump/kdump.rst
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002068 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002069
2070 Usage of bzImage for capturing the crash dump is recommended as
2071 one does not have to build two kernels. Same kernel can be used
2072 as production kernel and capture kernel. Above option should have
2073 gone away after relocatable bzImage support is introduced. But it
2074 is present because there are users out there who continue to use
2075 vmlinux for dump capture. This option should go away down the
2076 line.
2077
2078 Don't change this unless you know what you are doing.
2079
2080config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002081 bool "Build a relocatable kernel"
2082 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002083 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002084 This builds a kernel image that retains relocation information
2085 so it can be loaded someplace besides the default 1MB.
2086 The relocations tend to make the kernel binary about 10% larger,
2087 but are discarded at runtime.
2088
2089 One use is for the kexec on panic case where the recovery kernel
2090 must live at a different physical address than the primary
2091 kernel.
2092
2093 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2094 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002095 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002096
Kees Cook8ab38202013-10-10 17:18:14 -07002097config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002098 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002099 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002100 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002101 help
Baoquan Hee8581e32016-04-20 13:55:43 -07002102 In support of Kernel Address Space Layout Randomization (KASLR),
2103 this randomizes the physical address at which the kernel image
2104 is decompressed and the virtual address where the kernel
2105 image is mapped, as a security feature that deters exploit
2106 attempts relying on knowledge of the location of kernel
2107 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002108
Kees Cooked9f0072016-05-25 15:45:33 -07002109 On 64-bit, the kernel physical and virtual addresses are
2110 randomized separately. The physical address will be anywhere
2111 between 16MB and the top of physical memory (up to 64TB). The
2112 virtual address will be randomized from 16MB up to 1GB (9 bits
2113 of entropy). Note that this also reduces the memory space
2114 available to kernel modules from 1.5GB to 1GB.
2115
2116 On 32-bit, the kernel physical and virtual addresses are
2117 randomized together. They will be randomized from 16MB up to
2118 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002119
Baoquan Hee8581e32016-04-20 13:55:43 -07002120 Entropy is generated using the RDRAND instruction if it is
2121 supported. If RDTSC is supported, its value is mixed into
2122 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002123 supported, then entropy is read from the i8254 timer. The
2124 usable entropy is limited by the kernel being built using
2125 2GB addressing, and that PHYSICAL_ALIGN must be at a
2126 minimum of 2MB. As a result, only 10 bits of entropy are
2127 theoretically possible, but the implementations are further
2128 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002129
Ingo Molnar6807c842017-04-18 11:08:12 +02002130 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002131
2132# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002133config X86_NEED_RELOCS
2134 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002135 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002136
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002137config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002138 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002139 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002140 range 0x2000 0x1000000 if X86_32
2141 range 0x200000 0x1000000 if X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002142 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002143 This value puts the alignment restrictions on physical address
2144 where kernel is loaded and run from. Kernel is compiled for an
2145 address which meets above alignment restriction.
2146
2147 If bootloader loads the kernel at a non-aligned address and
2148 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2149 address aligned to above value and run from there.
2150
2151 If bootloader loads the kernel at a non-aligned address and
2152 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2153 load address and decompress itself to the address it has been
2154 compiled for and run from there. The address for which kernel is
2155 compiled already meets above alignment restrictions. Hence the
2156 end result is that kernel runs from a physical address meeting
2157 above alignment restrictions.
2158
Kees Cooka0215062013-07-08 09:15:17 -07002159 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2160 this value must be a multiple of 0x200000.
2161
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002162 Don't change this unless you know what you are doing.
2163
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002164config DYNAMIC_MEMORY_LAYOUT
2165 bool
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002166 help
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002167 This option makes base addresses of vmalloc and vmemmap as well as
2168 __PAGE_OFFSET movable during boot.
2169
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002170config RANDOMIZE_MEMORY
2171 bool "Randomize the kernel memory sections"
2172 depends on X86_64
2173 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002174 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002175 default RANDOMIZE_BASE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002176 help
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002177 Randomizes the base virtual address of kernel memory sections
2178 (physical memory mapping, vmalloc & vmemmap). This security feature
2179 makes exploits relying on predictable memory locations less reliable.
2180
2181 The order of allocations remains unchanged. Entropy is generated in
2182 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2183 configuration have in average 30,000 different possible virtual
2184 addresses for each memory section.
2185
Ingo Molnar6807c842017-04-18 11:08:12 +02002186 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002187
Thomas Garnier90397a42016-06-21 17:47:06 -07002188config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2189 hex "Physical memory mapping padding" if EXPERT
2190 depends on RANDOMIZE_MEMORY
2191 default "0xa" if MEMORY_HOTPLUG
2192 default "0x0"
2193 range 0x1 0x40 if MEMORY_HOTPLUG
2194 range 0x0 0x40
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002195 help
Thomas Garnier90397a42016-06-21 17:47:06 -07002196 Define the padding in terabytes added to the existing physical
2197 memory size during kernel memory randomization. It is useful
2198 for memory hotplug support but reduces the entropy available for
2199 address randomization.
2200
2201 If unsure, leave at the default value.
2202
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002203config HOTPLUG_CPU
Thomas Gleixnerbebd0242019-03-26 17:36:06 +01002204 def_bool y
Stephen Rothwell40b31362013-05-21 13:49:35 +10002205 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002206
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002207config BOOTPARAM_HOTPLUG_CPU0
2208 bool "Set default setting of cpu0_hotpluggable"
Kees Cook2c922cd2013-01-22 13:01:19 -08002209 depends on HOTPLUG_CPU
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002210 help
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002211 Set whether default state of cpu0_hotpluggable is on or off.
2212
2213 Say Y here to enable CPU0 hotplug by default. If this switch
2214 is turned on, there is no need to give cpu0_hotplug kernel
2215 parameter and the CPU0 hotplug feature is enabled by default.
2216
2217 Please note: there are two known CPU0 dependencies if you want
2218 to enable the CPU0 hotplug feature either by this switch or by
2219 cpu0_hotplug kernel parameter.
2220
2221 First, resume from hibernate or suspend always starts from CPU0.
2222 So hibernate and suspend are prevented if CPU0 is offline.
2223
2224 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2225 offline if any interrupt can not migrate out of CPU0. There may
2226 be other CPU0 dependencies.
2227
2228 Please make sure the dependencies are under your control before
2229 you enable this feature.
2230
2231 Say N if you don't want to enable CPU0 hotplug feature by default.
2232 You still can enable the CPU0 hotplug feature at boot by kernel
2233 parameter cpu0_hotplug.
2234
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002235config DEBUG_HOTPLUG_CPU0
2236 def_bool n
2237 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002238 depends on HOTPLUG_CPU
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002239 help
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002240 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2241 soon as possible and boots up userspace with CPU0 offlined. User
2242 can online CPU0 back after boot time.
2243
2244 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2245 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2246 compilation or giving cpu0_hotplug kernel parameter at boot.
2247
2248 If unsure, say N.
2249
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002250config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002251 def_bool n
2252 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002253 depends on COMPAT_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002254 help
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002255 Certain buggy versions of glibc will crash if they are
2256 presented with a 32-bit vDSO that is not mapped at the address
2257 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002258
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002259 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2260 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2261 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2262 the only released version with the bug, but OpenSUSE 9
2263 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002264
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002265 The symptom of the bug is that everything crashes on startup, saying:
2266 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2267
2268 Saying Y here changes the default value of the vdso32 boot
2269 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2270 This works around the glibc bug but hurts performance.
2271
2272 If unsure, say N: if you are compiling your own kernel, you
2273 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002274
Kees Cook3dc33bd2015-08-12 17:55:19 -07002275choice
2276 prompt "vsyscall table for legacy applications"
2277 depends on X86_64
Andy Lutomirski625b7b72019-06-26 21:45:07 -07002278 default LEGACY_VSYSCALL_XONLY
Kees Cook3dc33bd2015-08-12 17:55:19 -07002279 help
2280 Legacy user code that does not know how to find the vDSO expects
2281 to be able to issue three syscalls by calling fixed addresses in
2282 kernel space. Since this location is not randomized with ASLR,
2283 it can be used to assist security vulnerability exploitation.
2284
2285 This setting can be changed at boot time via the kernel command
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002286 line parameter vsyscall=[emulate|xonly|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002287
2288 On a system with recent enough glibc (2.14 or newer) and no
2289 static binaries, you can say None without a performance penalty
2290 to improve security.
2291
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002292 If unsure, select "Emulate execution only".
Kees Cook3dc33bd2015-08-12 17:55:19 -07002293
Kees Cook3dc33bd2015-08-12 17:55:19 -07002294 config LEGACY_VSYSCALL_EMULATE
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002295 bool "Full emulation"
Kees Cook3dc33bd2015-08-12 17:55:19 -07002296 help
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002297 The kernel traps and emulates calls into the fixed vsyscall
2298 address mapping. This makes the mapping non-executable, but
2299 it still contains readable known contents, which could be
2300 used in certain rare security vulnerability exploits. This
2301 configuration is recommended when using legacy userspace
2302 that still uses vsyscalls along with legacy binary
2303 instrumentation tools that require code to be readable.
2304
2305 An example of this type of legacy userspace is running
2306 Pin on an old binary that still uses vsyscalls.
2307
2308 config LEGACY_VSYSCALL_XONLY
2309 bool "Emulate execution only"
2310 help
2311 The kernel traps and emulates calls into the fixed vsyscall
2312 address mapping and does not allow reads. This
2313 configuration is recommended when userspace might use the
2314 legacy vsyscall area but support for legacy binary
2315 instrumentation of legacy code is not needed. It mitigates
2316 certain uses of the vsyscall area as an ASLR-bypassing
2317 buffer.
Kees Cook3dc33bd2015-08-12 17:55:19 -07002318
2319 config LEGACY_VSYSCALL_NONE
2320 bool "None"
2321 help
2322 There will be no vsyscall mapping at all. This will
2323 eliminate any risk of ASLR bypass due to the vsyscall
2324 fixed address mapping. Attempts to use the vsyscalls
2325 will be reported to dmesg, so that either old or
2326 malicious userspace programs can be identified.
2327
2328endchoice
2329
Tim Bird516cbf32008-08-12 12:52:36 -07002330config CMDLINE_BOOL
2331 bool "Built-in kernel command line"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002332 help
Tim Bird516cbf32008-08-12 12:52:36 -07002333 Allow for specifying boot arguments to the kernel at
2334 build time. On some systems (e.g. embedded ones), it is
2335 necessary or convenient to provide some or all of the
2336 kernel boot arguments with the kernel itself (that is,
2337 to not rely on the boot loader to provide them.)
2338
2339 To compile command line arguments into the kernel,
2340 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002341 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002342
2343 Systems with fully functional boot loaders (i.e. non-embedded)
2344 should leave this option set to 'N'.
2345
2346config CMDLINE
2347 string "Built-in kernel command string"
2348 depends on CMDLINE_BOOL
2349 default ""
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002350 help
Tim Bird516cbf32008-08-12 12:52:36 -07002351 Enter arguments here that should be compiled into the kernel
2352 image and used at boot time. If the boot loader provides a
2353 command line at boot time, it is appended to this string to
2354 form the full kernel command line, when the system boots.
2355
2356 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2357 change this behavior.
2358
2359 In most cases, the command line (whether built-in or provided
2360 by the boot loader) should specify the device for the root
2361 file system.
2362
2363config CMDLINE_OVERRIDE
2364 bool "Built-in command line overrides boot loader arguments"
Anders Roxell645e6462020-01-24 12:46:15 +01002365 depends on CMDLINE_BOOL && CMDLINE != ""
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002366 help
Tim Bird516cbf32008-08-12 12:52:36 -07002367 Set this option to 'Y' to have the kernel ignore the boot loader
2368 command line, and use ONLY the built-in command line.
2369
2370 This is used to work around broken boot loaders. This should
2371 be set to 'N' under normal conditions.
2372
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002373config MODIFY_LDT_SYSCALL
2374 bool "Enable the LDT (local descriptor table)" if EXPERT
2375 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002376 help
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002377 Linux can allow user programs to install a per-process x86
2378 Local Descriptor Table (LDT) using the modify_ldt(2) system
2379 call. This is required to run 16-bit or segmented code such as
2380 DOSEMU or some Wine programs. It is also used by some very old
2381 threading libraries.
2382
2383 Enabling this feature adds a small amount of overhead to
2384 context switches and increases the low-level kernel attack
2385 surface. Disabling it removes the modify_ldt(2) system call.
2386
2387 Saying 'N' here may make sense for embedded or server kernels.
2388
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002389source "kernel/livepatch/Kconfig"
2390
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002391endmenu
2392
Michal Hocko3072e412017-09-08 16:11:39 -07002393config ARCH_HAS_ADD_PAGES
2394 def_bool y
2395 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2396
Oscar Salvadorf91ef222021-05-04 18:39:51 -07002397config ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
2398 def_bool y
2399
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002400config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002401 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002402 depends on NUMA
2403
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002404menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002405
2406config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002407 def_bool y
Zhimin Gu44556532018-09-21 14:27:29 +08002408 depends on HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002409
2410source "kernel/power/Kconfig"
2411
2412source "drivers/acpi/Kconfig"
2413
Andi Kleena6b68072008-01-30 13:32:49 +01002414config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002415 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002416 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002417
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002418menuconfig APM
2419 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002420 depends on X86_32 && PM_SLEEP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002421 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002422 APM is a BIOS specification for saving power using several different
2423 techniques. This is mostly useful for battery powered laptops with
2424 APM compliant BIOSes. If you say Y here, the system time will be
2425 reset after a RESUME operation, the /proc/apm device will provide
2426 battery status information, and user-space programs will receive
2427 notification of APM "events" (e.g. battery status change).
2428
2429 If you select "Y" here, you can disable actual use of the APM
2430 BIOS by passing the "apm=off" option to the kernel at boot time.
2431
2432 Note that the APM support is almost completely disabled for
2433 machines with more than one CPU.
2434
2435 In order to use APM, you will need supporting software. For location
Mauro Carvalho Chehab151f4e22019-06-13 07:10:36 -03002436 and more information, read <file:Documentation/power/apm-acpi.rst>
Michael Witten2dc98fd2011-07-08 21:11:16 +00002437 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002438 <http://www.tldp.org/docs.html#howto>.
2439
2440 This driver does not spin down disk drives (see the hdparm(8)
2441 manpage ("man 8 hdparm") for that), and it doesn't turn off
2442 VESA-compliant "green" monitors.
2443
2444 This driver does not support the TI 4000M TravelMate and the ACER
2445 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2446 desktop machines also don't have compliant BIOSes, and this driver
2447 may cause those machines to panic during the boot phase.
2448
2449 Generally, if you don't have a battery in your machine, there isn't
2450 much point in using this driver and you should say N. If you get
2451 random kernel OOPSes or reboots that don't seem to be related to
2452 anything, try disabling/enabling this option (or disabling/enabling
2453 APM in your BIOS).
2454
2455 Some other things you should try when experiencing seemingly random,
2456 "weird" problems:
2457
2458 1) make sure that you have enough swap space and that it is
2459 enabled.
2460 2) pass the "no-hlt" option to the kernel
2461 3) switch on floating point emulation in the kernel and pass
2462 the "no387" option to the kernel
2463 4) pass the "floppy=nodma" option to the kernel
2464 5) pass the "mem=4M" option to the kernel (thereby disabling
2465 all but the first 4 MB of RAM)
2466 6) make sure that the CPU is not over clocked.
2467 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2468 8) disable the cache from your BIOS settings
2469 9) install a fan for the video card or exchange video RAM
2470 10) install a better fan for the CPU
2471 11) exchange RAM chips
2472 12) exchange the motherboard.
2473
2474 To compile this driver as a module, choose M here: the
2475 module will be called apm.
2476
2477if APM
2478
2479config APM_IGNORE_USER_SUSPEND
2480 bool "Ignore USER SUSPEND"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002481 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002482 This option will ignore USER SUSPEND requests. On machines with a
2483 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2484 series notebooks, it is necessary to say Y because of a BIOS bug.
2485
2486config APM_DO_ENABLE
2487 bool "Enable PM at boot time"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002488 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002489 Enable APM features at boot time. From page 36 of the APM BIOS
2490 specification: "When disabled, the APM BIOS does not automatically
2491 power manage devices, enter the Standby State, enter the Suspend
2492 State, or take power saving steps in response to CPU Idle calls."
2493 This driver will make CPU Idle calls when Linux is idle (unless this
2494 feature is turned off -- see "Do CPU IDLE calls", below). This
2495 should always save battery power, but more complicated APM features
2496 will be dependent on your BIOS implementation. You may need to turn
2497 this option off if your computer hangs at boot time when using APM
2498 support, or if it beeps continuously instead of suspending. Turn
2499 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2500 T400CDT. This is off by default since most machines do fine without
2501 this feature.
2502
2503config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002504 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002505 bool "Make CPU Idle calls when idle"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002506 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002507 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2508 On some machines, this can activate improved power savings, such as
2509 a slowed CPU clock rate, when the machine is idle. These idle calls
2510 are made after the idle loop has run for some length of time (e.g.,
2511 333 mS). On some machines, this will cause a hang at boot time or
2512 whenever the CPU becomes idle. (On machines with more than one CPU,
2513 this option does nothing.)
2514
2515config APM_DISPLAY_BLANK
2516 bool "Enable console blanking using APM"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002517 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002518 Enable console blanking using the APM. Some laptops can use this to
2519 turn off the LCD backlight when the screen blanker of the Linux
2520 virtual console blanks the screen. Note that this is only used by
2521 the virtual console screen blanker, and won't turn off the backlight
2522 when using the X Window system. This also doesn't have anything to
2523 do with your VESA-compliant power-saving monitor. Further, this
2524 option doesn't work for all laptops -- it might not turn off your
2525 backlight at all, or it might print a lot of errors to the console,
2526 especially if you are using gpm.
2527
2528config APM_ALLOW_INTS
2529 bool "Allow interrupts during APM BIOS calls"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002530 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002531 Normally we disable external interrupts while we are making calls to
2532 the APM BIOS as a measure to lessen the effects of a badly behaving
2533 BIOS implementation. The BIOS should reenable interrupts if it
2534 needs to. Unfortunately, some BIOSes do not -- especially those in
2535 many of the newer IBM Thinkpads. If you experience hangs when you
2536 suspend, try setting this to Y. Otherwise, say N.
2537
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002538endif # APM
2539
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002540source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002541
2542source "drivers/cpuidle/Kconfig"
2543
Andy Henroid27471fd2008-10-09 11:45:22 -07002544source "drivers/idle/Kconfig"
2545
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002546endmenu
2547
2548
2549menu "Bus options (PCI etc.)"
2550
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002551choice
2552 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002553 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002554 default PCI_GOANY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002555 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002556 On PCI systems, the BIOS can be used to detect the PCI devices and
2557 determine their configuration. However, some old PCI motherboards
2558 have BIOS bugs and may crash if this is done. Also, some embedded
2559 PCI-based systems don't have any BIOS at all. Linux can also try to
2560 detect the PCI hardware directly without using the BIOS.
2561
2562 With this option, you can specify how Linux should detect the
2563 PCI devices. If you choose "BIOS", the BIOS will be used,
2564 if you choose "Direct", the BIOS won't be used, and if you
2565 choose "MMConfig", then PCI Express MMCONFIG will be used.
2566 If you choose "Any", the kernel will try MMCONFIG, then the
2567 direct access method and falls back to the BIOS if that doesn't
2568 work. If unsure, go with the default, which is "Any".
2569
2570config PCI_GOBIOS
2571 bool "BIOS"
2572
2573config PCI_GOMMCONFIG
2574 bool "MMConfig"
2575
2576config PCI_GODIRECT
2577 bool "Direct"
2578
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002579config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002580 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002581 depends on OLPC
2582
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002583config PCI_GOANY
2584 bool "Any"
2585
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002586endchoice
2587
2588config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002589 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002590 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002591
2592# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2593config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002594 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002595 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002596
2597config PCI_MMCONFIG
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002598 bool "Support mmconfig PCI config space access" if X86_64
2599 default y
Andy Shevchenko4590d982021-02-11 15:40:02 +02002600 depends on PCI && (ACPI || JAILHOUSE_GUEST)
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002601 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002602
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002603config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002604 def_bool y
2605 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002606
Alex Nixonb5401a92010-03-18 16:31:34 -04002607config PCI_XEN
2608 def_bool y
2609 depends on PCI && XEN
2610 select SWIOTLB_XEN
2611
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002612config MMCONF_FAM10H
2613 def_bool y
2614 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002615
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002616config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002617 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002618 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002619 help
2620 Read the PCI windows out of the CNB20LE host bridge. This allows
2621 PCI hotplug to work on systems with the CNB20LE chipset which do
2622 not have ACPI.
2623
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002624 There's no public spec for this chipset, and this functionality
2625 is known to be incomplete.
2626
2627 You should say N unless you know you need this.
2628
William Breathitt Gray3a495512016-05-27 18:08:27 -04002629config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002630 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002631 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002632 Expose ISA bus device drivers and options available for selection and
2633 configuration. Enable this option if your target machine has an ISA
2634 bus. ISA is an older system, displaced by PCI and newer bus
2635 architectures -- if your target machine is modern, it probably does
2636 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002637
2638 If unsure, say N.
2639
David Rientjes1c00f012011-03-22 16:34:59 -07002640# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002641config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002642 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2643 default y
2644 help
2645 Enables ISA-style DMA support for devices requiring such controllers.
2646 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002647
Linus Torvalds51e68d02016-05-21 10:25:19 -07002648if X86_32
2649
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002650config ISA
2651 bool "ISA support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002652 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002653 Find out whether you have ISA slots on your motherboard. ISA is the
2654 name of a bus system, i.e. the way the CPU talks to the other stuff
2655 inside your box. Other bus systems are PCI, EISA, MicroChannel
2656 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2657 newer boards don't support it. If you have ISA, say Y, otherwise N.
2658
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002659config SCx200
2660 tristate "NatSemi SCx200 support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002661 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002662 This provides basic support for National Semiconductor's
2663 (now AMD's) Geode processors. The driver probes for the
2664 PCI-IDs of several on-chip devices, so its a good dependency
2665 for other scx200_* drivers.
2666
2667 If compiled as a module, the driver is named scx200.
2668
2669config SCx200HR_TIMER
2670 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002671 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002672 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002673 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002674 This driver provides a clocksource built upon the on-chip
2675 27MHz high-resolution timer. Its also a workaround for
2676 NSC Geode SC-1100's buggy TSC, which loses time when the
2677 processor goes idle (as is done by the scheduler). The
2678 other workaround is idle=poll boot option.
2679
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002680config OLPC
2681 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002682 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002683 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002684 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002685 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002686 select IRQ_DOMAIN
Lubomir Rintel0c3d9312019-05-13 09:56:37 +02002687 select OLPC_EC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002688 help
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002689 Add support for detecting the unique features of the OLPC
2690 XO hardware.
2691
Daniel Drakea3128582011-06-25 17:34:10 +01002692config OLPC_XO1_PM
2693 bool "OLPC XO-1 Power Management"
Borislav Petkovfa112cf2018-10-05 15:13:07 +02002694 depends on OLPC && MFD_CS5535=y && PM_SLEEP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002695 help
Daniel Drake97c4cb72011-06-25 17:34:11 +01002696 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002697
Daniel Drakecfee9592011-06-25 17:34:17 +01002698config OLPC_XO1_RTC
2699 bool "OLPC XO-1 Real Time Clock"
2700 depends on OLPC_XO1_PM && RTC_DRV_CMOS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002701 help
Daniel Drakecfee9592011-06-25 17:34:17 +01002702 Add support for the XO-1 real time clock, which can be used as a
2703 programmable wakeup source.
2704
Daniel Drake7feda8e2011-06-25 17:34:12 +01002705config OLPC_XO1_SCI
2706 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002707 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002708 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002709 select POWER_SUPPLY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002710 help
Daniel Drake7feda8e2011-06-25 17:34:12 +01002711 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002712 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002713 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002714 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002715 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002716 - AC adapter status updates
2717 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002718
Daniel Drakea0f30f52011-06-25 17:34:18 +01002719config OLPC_XO15_SCI
2720 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002721 depends on OLPC && ACPI
2722 select POWER_SUPPLY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002723 help
Daniel Drakea0f30f52011-06-25 17:34:18 +01002724 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2725 - EC-driven system wakeups
2726 - AC adapter status updates
2727 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002728
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002729config ALIX
2730 bool "PCEngines ALIX System Support (LED setup)"
2731 select GPIOLIB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002732 help
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002733 This option enables system support for the PCEngines ALIX.
2734 At present this just sets up LEDs for GPIO control on
2735 ALIX2/3/6 boards. However, other system specific setup should
2736 get added here.
2737
2738 Note: You must still enable the drivers for GPIO and LED support
2739 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2740
2741 Note: You have to set alix.force=1 for boards with Award BIOS.
2742
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002743config NET5501
2744 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2745 select GPIOLIB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002746 help
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002747 This option enables system support for the Soekris Engineering net5501.
2748
Philip A. Prindeville31970592012-01-14 01:45:39 -07002749config GEOS
2750 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2751 select GPIOLIB
2752 depends on DMI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002753 help
Philip A. Prindeville31970592012-01-14 01:45:39 -07002754 This option enables system support for the Traverse Technologies GEOS.
2755
Vivien Didelot7d029122013-01-04 16:18:14 -05002756config TS5500
2757 bool "Technologic Systems TS-5500 platform support"
2758 depends on MELAN
2759 select CHECK_SIGNATURE
2760 select NEW_LEDS
2761 select LEDS_CLASS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002762 help
Vivien Didelot7d029122013-01-04 16:18:14 -05002763 This option enables system support for the Technologic Systems TS-5500.
2764
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002765endif # X86_32
2766
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002767config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002768 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002769 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002770
David Herrmanne3263ab2013-08-02 14:05:22 +02002771config X86_SYSFB
2772 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2773 help
2774 Firmwares often provide initial graphics framebuffers so the BIOS,
2775 bootloader or kernel can show basic video-output during boot for
2776 user-guidance and debugging. Historically, x86 used the VESA BIOS
2777 Extensions and EFI-framebuffers for this, which are mostly limited
2778 to x86.
2779 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2780 framebuffers so the new generic system-framebuffer drivers can be
2781 used on x86. If the framebuffer is not compatible with the generic
Nikolas Nybye3a5dc02018-08-25 19:10:54 -04002782 modes, it is advertised as fallback platform framebuffer so legacy
David Herrmanne3263ab2013-08-02 14:05:22 +02002783 drivers like efifb, vesafb and uvesafb can pick it up.
2784 If this option is not selected, all system framebuffers are always
2785 marked as fallback platform framebuffers as usual.
2786
2787 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2788 not be able to pick up generic system framebuffers if this option
2789 is selected. You are highly encouraged to enable simplefb as
2790 replacement if you select this option. simplefb can correctly deal
2791 with generic system framebuffers. But you should still keep vesafb
2792 and others enabled as fallback if a system framebuffer is
2793 incompatible with simplefb.
2794
2795 If unsure, say Y.
2796
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002797endmenu
2798
2799
Christoph Hellwig15724972018-07-31 13:39:30 +02002800menu "Binary Emulations"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002801
2802config IA32_EMULATION
2803 bool "IA32 Emulation"
2804 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002805 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002806 select BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002807 select COMPAT_OLD_SIGACTION
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002808 help
H. J. Lu5fd92e62012-02-19 10:40:03 -08002809 Include code to run legacy 32-bit programs under a
2810 64-bit kernel. You should likely turn this on, unless you're
2811 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002812
2813config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002814 tristate "IA32 a.out support"
2815 depends on IA32_EMULATION
Borislav Petkoveac61652019-03-05 15:47:51 +01002816 depends on BROKEN
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002817 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002818 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002819
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002820config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002821 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002822 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002823 help
H. J. Lu5fd92e62012-02-19 10:40:03 -08002824 Include code to run binaries for the x32 native 32-bit ABI
2825 for 64-bit processors. An x32 process gets access to the
2826 full 64-bit register file and wide data path while leaving
2827 pointers at 32 bits for smaller memory footprint.
2828
2829 You will need a recent binutils (2.22 or later) with
2830 elf32_x86_64 support enabled to compile a kernel with this
2831 option set.
2832
Ingo Molnar953fee12016-11-15 10:22:52 +01002833config COMPAT_32
2834 def_bool y
2835 depends on IA32_EMULATION || X86_32
2836 select HAVE_UID16
2837 select OLD_SIGSUSPEND3
2838
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002839config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002840 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002841 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002842
Jan Beulich3120e252012-09-10 12:41:45 +01002843if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002844config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002845 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002846
2847config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002848 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002849 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002850endif
David Howellsee009e4a02011-03-07 15:06:20 +00002851
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002852endmenu
2853
2854
Keith Packarde5beae12008-11-03 18:21:45 +01002855config HAVE_ATOMIC_IOMAP
2856 def_bool y
2857 depends on X86_32
2858
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002859source "drivers/firmware/Kconfig"
2860
Avi Kivityedf88412007-12-16 11:02:48 +02002861source "arch/x86/kvm/Kconfig"
Jason A. Donenfeld5e8ebd82020-03-26 17:00:58 +09002862
2863source "arch/x86/Kconfig.assembler"