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Greg Kroah-Hartmanb2441312017-11-01 15:07:57 +01001# SPDX-License-Identifier: GPL-2.0
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01002# Select 32 or 64 bit
3config 64BIT
Masahiro Yamada104daea2018-05-28 18:21:40 +09004 bool "64-bit kernel" if "$(ARCH)" = "x86"
5 default "$(ARCH)" != "i386"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09006 help
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01007 Say yes to build a 64-bit kernel - formerly known as x86_64
8 Say no to build a 32-bit kernel - formerly known as i386
9
10config X86_32
Jan Beulich3120e252012-09-10 12:41:45 +010011 def_bool y
12 depends on !64BIT
Ingo Molnar341c7872016-11-15 10:04:55 +010013 # Options that are inherently 32-bit kernel only:
14 select ARCH_WANT_IPC_PARSE_VERSION
15 select CLKSRC_I8253
16 select CLONE_BACKWARDS
Thomas Gleixner117ed452019-04-14 18:00:08 +020017 select HAVE_DEBUG_STACKOVERFLOW
Ingo Molnar341c7872016-11-15 10:04:55 +010018 select MODULES_USE_ELF_REL
19 select OLD_SIGACTION
Vincenzo Frascino7ac87072019-06-21 10:52:49 +010020 select GENERIC_VDSO_32
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +010021
22config X86_64
Jan Beulich3120e252012-09-10 12:41:45 +010023 def_bool y
24 depends on 64BIT
Ingo Molnard94e0682016-11-15 10:11:57 +010025 # Options that are inherently 64-bit kernel only:
Alexandre Ghiti4eb07162019-05-13 17:19:04 -070026 select ARCH_HAS_GIGANTIC_PAGE
Ard Biesheuvelc12d3362019-11-08 13:22:27 +010027 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
Ingo Molnard94e0682016-11-15 10:11:57 +010028 select ARCH_USE_CMPXCHG_LOCKREF
29 select HAVE_ARCH_SOFT_DIRTY
30 select MODULES_USE_ELF_RELA
Christoph Hellwigf616ab52018-05-09 06:53:49 +020031 select NEED_DMA_MAP_STATE
Christoph Hellwig09230cb2018-04-24 09:00:54 +020032 select SWIOTLB
Sam Ravnborg1032c0b2007-11-06 21:35:08 +010033
Steven Rostedt (VMware)518049d2019-05-10 12:05:46 -040034config FORCE_DYNAMIC_FTRACE
35 def_bool y
36 depends on X86_32
37 depends on FUNCTION_TRACER
38 select DYNAMIC_FTRACE
39 help
40 We keep the static function tracing (!DYNAMIC_FTRACE) around
41 in order to test the non static function tracing in the
42 generic code, as other architectures still use it. But we
43 only need to keep it around for x86_64. No need to keep it
44 for x86_32. For x86_32, force DYNAMIC_FTRACE.
Ingo Molnard94e0682016-11-15 10:11:57 +010045#
46# Arch settings
47#
48# ( Note that options that are marked 'if X86_64' could in principle be
49# ported to 32-bit as well. )
50#
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +010051config X86
Harvey Harrison3c2362e2008-01-30 13:31:03 +010052 def_bool y
Ingo Molnarc763ea22016-11-15 10:26:39 +010053 #
54 # Note: keep this list sorted alphabetically
55 #
Ingo Molnar6471b822015-06-03 10:00:13 +020056 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
57 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
Yury Norov942fa982018-05-16 11:18:49 +030058 select ARCH_32BIT_OFF_T if X86_32
Thomas Gleixner2a21ad52018-09-17 14:45:35 +020059 select ARCH_CLOCKSOURCE_INIT
Ingo Molnarc763ea22016-11-15 10:26:39 +010060 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
Laura Abbottfa5b6ec2017-01-10 13:35:40 -080061 select ARCH_HAS_DEBUG_VIRTUAL
Anshuman Khandual399145f2020-06-04 16:47:15 -070062 select ARCH_HAS_DEBUG_VM_PGTABLE if !X86_PAE
Dan Williams21266be2015-11-19 18:19:29 -080063 select ARCH_HAS_DEVMEM_IS_ALLOWED
Douglas Andersonb1a57bb2020-05-07 13:08:42 -070064 select ARCH_HAS_EARLY_DEBUG if KGDB
Ingo Molnar6471b822015-06-03 10:00:13 +020065 select ARCH_HAS_ELF_RANDOMIZE
Linus Torvalds72d93102014-09-13 11:14:53 -070066 select ARCH_HAS_FAST_MULTIPLIER
Dave Hansen316d0972018-04-20 15:20:28 -070067 select ARCH_HAS_FILTER_PGPROT
Daniel Micay6974f0c2017-07-12 14:36:10 -070068 select ARCH_HAS_FORTIFY_SOURCE
Riku Voipio957e3fa2014-12-12 16:57:44 -080069 select ARCH_HAS_GCOV_PROFILE_ALL
Peter Zijlstra0f1441b2020-06-12 16:05:26 +020070 select ARCH_HAS_KCOV if X86_64 && STACK_VALIDATION
Thiago Jung Bauermann0c9c1d52019-08-06 01:49:14 -030071 select ARCH_HAS_MEM_ENCRYPT
Mathieu Desnoyers10bcc802018-01-29 15:20:18 -050072 select ARCH_HAS_MEMBARRIER_SYNC_CORE
Daniel Borkmann0ebeea82020-05-15 12:11:16 +020073 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
Ingo Molnarc763ea22016-11-15 10:26:39 +010074 select ARCH_HAS_PMEM_API if X86_64
Robin Murphy17596732019-07-16 16:30:47 -070075 select ARCH_HAS_PTE_DEVMAP if X86_64
Laurent Dufour3010a5e2018-06-07 17:06:08 -070076 select ARCH_HAS_PTE_SPECIAL
Dan Williams0aed55a2017-05-29 12:22:50 -070077 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Dan Williams092b31a2018-07-08 13:46:17 -070078 select ARCH_HAS_UACCESS_MCSAFE if X86_64 && X86_MCE
Daniel Borkmannd2852a22017-02-21 16:09:33 +010079 select ARCH_HAS_SET_MEMORY
Rick Edgecombed253ca02019-04-25 17:11:34 -070080 select ARCH_HAS_SET_DIRECT_MAP
Laura Abbottad21fc42017-02-06 16:31:57 -080081 select ARCH_HAS_STRICT_KERNEL_RWX
82 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050083 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Brian Gerst25c619e2020-03-13 15:51:42 -040084 select ARCH_HAS_SYSCALL_WRAPPER
Andrey Ryabininc6d30852016-01-20 15:00:55 -080085 select ARCH_HAS_UBSAN_SANITIZE_ALL
Zong Li7e01ccb2020-06-03 16:03:58 -070086 select ARCH_HAS_DEBUG_WX
Ingo Molnar6471b822015-06-03 10:00:13 +020087 select ARCH_HAVE_NMI_SAFE_CMPXCHG
88 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040089 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080090 select ARCH_MIGHT_HAVE_PC_SERIO
Thomas Gleixner3599fe12019-04-25 11:45:22 +020091 select ARCH_STACKWALK
Arnd Bergmann2c870e62018-07-24 11:48:45 +020092 select ARCH_SUPPORTS_ACPI
Ingo Molnar6471b822015-06-03 10:00:13 +020093 select ARCH_SUPPORTS_ATOMIC_RMW
Ingo Molnar6471b822015-06-03 10:00:13 +020094 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
95 select ARCH_USE_BUILTIN_BSWAP
Ingo Molnar6471b822015-06-03 10:00:13 +020096 select ARCH_USE_QUEUED_RWLOCKS
97 select ARCH_USE_QUEUED_SPINLOCKS
Mark Brown2ce0d7f2020-04-16 19:24:02 +010098 select ARCH_USE_SYM_ANNOTATIONS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -070099 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Daniel Borkmann81c22042019-12-09 16:08:03 +0100100 select ARCH_WANT_DEFAULT_BPF_JIT if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100101 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Alexandre Ghiti3876d4a2019-06-27 15:00:11 -0700102 select ARCH_WANT_HUGE_PMD_SHARE
Huang Ying38d8b4e2017-07-06 15:37:18 -0700103 select ARCH_WANTS_THP_SWAP if X86_64
Shile Zhang10916702019-12-04 08:46:31 +0800104 select BUILDTIME_TABLE_SORT
Ingo Molnar6471b822015-06-03 10:00:13 +0200105 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +0200106 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
107 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +0200108 select DCACHE_WORD_ACCESS
Linus Torvalds45471cd2015-06-24 19:52:06 -0700109 select EDAC_ATOMIC_SCRUB
110 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +0200111 select GENERIC_CLOCKEVENTS
112 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
113 select GENERIC_CLOCKEVENTS_MIN_ADJUST
114 select GENERIC_CMOS_UPDATE
115 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +0100116 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +0200117 select GENERIC_EARLY_IOREMAP
Thomas Gleixner27d6b4d2020-07-23 00:00:04 +0200118 select GENERIC_ENTRY
Ingo Molnar6471b822015-06-03 10:00:13 +0200119 select GENERIC_FIND_FIRST_BIT
120 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +0200121 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +0200122 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +0200123 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200124 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200125 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200126 select GENERIC_IRQ_SHOW
127 select GENERIC_PENDING_IRQ if SMP
Steven Price2ae27132020-02-03 17:36:24 -0800128 select GENERIC_PTDUMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200129 select GENERIC_SMP_IDLE_THREAD
130 select GENERIC_STRNCPY_FROM_USER
131 select GENERIC_STRNLEN_USER
132 select GENERIC_TIME_VSYSCALL
Vincenzo Frascino7ac87072019-06-21 10:52:49 +0100133 select GENERIC_GETTIMEOFDAY
Dmitry Safonov550a77a2019-11-12 01:27:11 +0000134 select GENERIC_VDSO_TIME_NS
Christoph Hellwig39656e82019-07-11 20:56:49 -0700135 select GUP_GET_PTE_LOW_HIGH if X86_PAE
Hans de Goede17e58882020-01-23 22:02:42 +0100136 select HARDIRQS_SW_RESEND
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200137 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200138 select HAVE_ACPI_APEI if ACPI
139 select HAVE_ACPI_APEI_NMI if ACPI
140 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200141 select HAVE_ARCH_AUDITSYSCALL
142 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
143 select HAVE_ARCH_JUMP_LABEL
Ard Biesheuvelb34006c2018-09-18 23:51:41 -0700144 select HAVE_ARCH_JUMP_LABEL_RELATIVE
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800145 select HAVE_ARCH_KASAN if X86_64
Daniel Axtens0609ae02019-11-30 17:55:00 -0800146 select HAVE_ARCH_KASAN_VMALLOC if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200147 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800148 select HAVE_ARCH_MMAP_RND_BITS if MMU
149 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300150 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ard Biesheuvel271ca782018-08-21 21:56:00 -0700151 select HAVE_ARCH_PREL32_RELOCATIONS
Ingo Molnar6471b822015-06-03 10:00:13 +0200152 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700153 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Alexander Popovafaef012018-08-17 01:16:58 +0300154 select HAVE_ARCH_STACKLEAK
Ingo Molnar6471b822015-06-03 10:00:13 +0200155 select HAVE_ARCH_TRACEHOOK
156 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Matthew Wilcoxa00cc7d2017-02-24 14:57:02 -0800157 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
Peter Xub64d8d12020-04-20 18:13:45 -0700158 select HAVE_ARCH_USERFAULTFD_WP if X86_64 && USERFAULTFD
Andy Lutomirskie37e43a2016-08-11 02:35:23 -0700159 select HAVE_ARCH_VMAP_STACK if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100160 select HAVE_ARCH_WITHIN_STACK_FRAMES
Masahiro Yamada2ff2b7e2019-08-19 14:54:20 +0900161 select HAVE_ASM_MODVERSIONS
Ingo Molnar6471b822015-06-03 10:00:13 +0200162 select HAVE_CMPXCHG_DOUBLE
163 select HAVE_CMPXCHG_LOCAL
164 select HAVE_CONTEXT_TRACKING if X86_64
165 select HAVE_C_RECORDMCOUNT
166 select HAVE_DEBUG_KMEMLEAK
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700167 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400168 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900169 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Steven Rostedt (VMware)562955f2019-11-08 13:11:39 -0500170 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
Wang YanQing03f57812018-05-03 14:10:43 +0800171 select HAVE_EBPF_JIT
Johannes Berg58340a02008-07-25 01:45:33 -0700172 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Christoph Hellwig6630a8e2018-11-15 20:05:37 +0100173 select HAVE_EISA
Jiri Slaby5f56a5d2016-05-20 17:00:16 -0700174 select HAVE_EXIT_THREAD
Christoph Hellwig67a929e2019-07-11 20:57:14 -0700175 select HAVE_FAST_GUP
Steven Rostedt (VMware)644e0e82017-03-23 10:33:52 -0400176 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
Ingo Molnar6471b822015-06-03 10:00:13 +0200177 select HAVE_FTRACE_MCOUNT_RECORD
Ingo Molnar6471b822015-06-03 10:00:13 +0200178 select HAVE_FUNCTION_GRAPH_TRACER
179 select HAVE_FUNCTION_TRACER
Emese Revfy6b90bd42016-05-24 00:09:38 +0200180 select HAVE_GCC_PLUGINS
K.Prasad0067f122009-06-01 23:43:57 +0530181 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200182 select HAVE_IDE
183 select HAVE_IOREMAP_PROT
Ingo Molnar6471b822015-06-03 10:00:13 +0200184 select HAVE_IRQ_TIME_ACCOUNTING
185 select HAVE_KERNEL_BZIP2
186 select HAVE_KERNEL_GZIP
187 select HAVE_KERNEL_LZ4
188 select HAVE_KERNEL_LZMA
189 select HAVE_KERNEL_LZO
190 select HAVE_KERNEL_XZ
Nick Terrellfb46d052020-07-30 12:08:39 -0700191 select HAVE_KERNEL_ZSTD
Ingo Molnar6471b822015-06-03 10:00:13 +0200192 select HAVE_KPROBES
193 select HAVE_KPROBES_ON_FTRACE
Masami Hiramatsu540adea2018-01-13 02:55:03 +0900194 select HAVE_FUNCTION_ERROR_INJECTION
Ingo Molnar6471b822015-06-03 10:00:13 +0200195 select HAVE_KRETPROBES
196 select HAVE_KVM
197 select HAVE_LIVEPATCH if X86_64
Frederic Weisbecker01027522010-04-11 18:55:56 +0200198 select HAVE_MIXED_BREAKPOINTS_REGS
Josh Poimboeufee9f8fc2017-07-24 18:36:57 -0500199 select HAVE_MOD_ARCH_SPECIFIC
Joel Fernandes (Google)9f132f72019-01-03 15:28:41 -0800200 select HAVE_MOVE_PMD
Petr Mladek42a0bb32016-05-20 17:00:33 -0700201 select HAVE_NMI
Ingo Molnar6471b822015-06-03 10:00:13 +0200202 select HAVE_OPROFILE
203 select HAVE_OPTPROBES
204 select HAVE_PCSPKR_PLATFORM
205 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200206 select HAVE_PERF_EVENTS_NMI
Nicholas Piggin92e5aae2017-08-18 15:15:51 -0700207 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
Christoph Hellwigeb01d422018-11-15 20:05:32 +0100208 select HAVE_PCI
Jiri Olsac5e63192012-08-07 15:20:36 +0200209 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200210 select HAVE_PERF_USER_STACK_DUMP
Peter Zijlstraff2e6d722020-02-03 17:37:02 -0800211 select MMU_GATHER_RCU_TABLE_FREE if PARAVIRT
Thomas Gleixner00998082020-07-30 12:14:07 +0200212 select HAVE_POSIX_CPU_TIMERS_TASK_WORK
Ingo Molnar6471b822015-06-03 10:00:13 +0200213 select HAVE_REGS_AND_STACK_ACCESS_API
Jiri Slaby6415b382018-05-18 08:47:13 +0200214 select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION
Masami Hiramatsu3c88ee194c2018-04-25 21:20:57 +0900215 select HAVE_FUNCTION_ARG_ACCESS_API
Masahiro Yamadad148eac2018-06-14 19:36:45 +0900216 select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
Ingo Molnarc763ea22016-11-15 10:26:39 +0100217 select HAVE_STACK_VALIDATION if X86_64
Josh Poimboeufe6d6c072020-08-18 15:57:44 +0200218 select HAVE_STATIC_CALL
Josh Poimboeuf1e7e4782020-08-18 15:57:45 +0200219 select HAVE_STATIC_CALL_INLINE if HAVE_STACK_VALIDATION
Mathieu Desnoyersd6761b82018-06-02 08:43:58 -0400220 select HAVE_RSEQ
Ingo Molnar6471b822015-06-03 10:00:13 +0200221 select HAVE_SYSCALL_TRACEPOINTS
Ingo Molnar6471b822015-06-03 10:00:13 +0200222 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300223 select HAVE_USER_RETURN_NOTIFIER
Vincenzo Frascino7ac87072019-06-21 10:52:49 +0100224 select HAVE_GENERIC_VDSO
Thomas Gleixner05736e42018-05-29 17:48:27 +0200225 select HOTPLUG_SMT if SMP
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100226 select IRQ_FORCED_THREADING
Christoph Hellwig86596f02018-04-05 09:44:52 +0200227 select NEED_SG_DMA_LENGTH
Christoph Hellwig2eac9c22018-11-15 20:05:33 +0100228 select PCI_DOMAINS if PCI
Sinan Kaya625210c2019-01-21 23:19:58 +0000229 select PCI_LOCKLESS_CONFIG if PCI
Ingo Molnar6471b822015-06-03 10:00:13 +0200230 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500231 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200232 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200233 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500234 select SRCU
Josh Poimboeuf1e7e4782020-08-18 15:57:45 +0200235 select STACK_VALIDATION if HAVE_STACK_VALIDATION && (HAVE_STATIC_CALL_INLINE || RETPOLINE)
Ingo Molnar6471b822015-06-03 10:00:13 +0200236 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700237 select THREAD_INFO_IN_TASK
Ingo Molnar6471b822015-06-03 10:00:13 +0200238 select USER_STACKTRACE_SUPPORT
239 select VIRT_TO_BUS
Ingo Molnar3b02a052020-04-13 09:44:39 +0200240 select HAVE_ARCH_KCSAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200241 select X86_FEATURE_NAMES if PROC_FS
Aubrey Li0c608da2019-06-06 09:22:35 +0800242 select PROC_PID_ARCH_STATUS if PROC_FS
Nayna Jain9e2b4be2020-03-08 20:57:51 -0400243 imply IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI
Balbir Singh7d8330a2008-02-10 12:46:28 +0530244
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200245config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100246 def_bool y
247 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200248
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700249config OUTPUT_FORMAT
250 string
251 default "elf32-i386" if X86_32
252 default "elf64-x86-64" if X86_64
253
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100254config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100255 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100256
257config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100258 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100259
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100260config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100261 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100262
Daniel Cashman9e08f572016-01-14 15:20:06 -0800263config ARCH_MMAP_RND_BITS_MIN
264 default 28 if 64BIT
265 default 8
266
267config ARCH_MMAP_RND_BITS_MAX
268 default 32 if 64BIT
269 default 16
270
271config ARCH_MMAP_RND_COMPAT_BITS_MIN
272 default 8
273
274config ARCH_MMAP_RND_COMPAT_BITS_MAX
275 default 16
276
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100277config SBUS
278 bool
279
280config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100281 def_bool y
282 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100283
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100284config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100285 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100286 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000287 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
288
289config GENERIC_BUG_RELATIVE_POINTERS
290 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100291
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100292config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100293 def_bool y
294 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100295
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100296config GENERIC_CALIBRATE_DELAY
297 def_bool y
298
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800299config ARCH_HAS_CPU_RELAX
300 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100301
Pekka Enberg1b27d052008-04-28 02:12:22 -0700302config ARCH_HAS_CACHE_LINE_SIZE
303 def_bool y
304
Dave Hansen316d0972018-04-20 15:20:28 -0700305config ARCH_HAS_FILTER_PGPROT
306 def_bool y
307
Mike Travisdd5af902008-01-30 13:33:32 +0100308config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900309 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100310
Tejun Heo08fc4582009-08-14 15:00:49 +0900311config NEED_PER_CPU_EMBED_FIRST_CHUNK
312 def_bool y
313
314config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900315 def_bool y
316
Johannes Berg801e4062007-12-08 02:12:39 +0100317config ARCH_HIBERNATION_POSSIBLE
318 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100319
Johannes Bergf4cb5702007-12-08 02:14:00 +0100320config ARCH_SUSPEND_POSSIBLE
321 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100322
Steve Capper53313b22013-04-30 08:03:42 +0100323config ARCH_WANT_GENERAL_HUGETLB
324 def_bool y
325
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100326config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000327 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100328
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100329config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000330 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100331
Akinobu Mita6a11f752009-03-31 15:23:17 -0700332config ARCH_SUPPORTS_DEBUG_PAGEALLOC
333 def_bool y
334
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300335config KASAN_SHADOW_OFFSET
336 hex
337 depends on KASAN
338 default 0xdffffc0000000000
339
Shane Wang69575d32009-09-01 18:25:07 -0700340config HAVE_INTEL_TXT
341 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700342 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700343
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100344config X86_32_SMP
345 def_bool y
346 depends on X86_32 && SMP
347
348config X86_64_SMP
349 def_bool y
350 depends on X86_64 && SMP
351
Tejun Heoccbeed32009-02-09 22:17:40 +0900352config X86_32_LAZY_GS
353 def_bool y
Masahiro Yamada8458f8c2018-06-14 19:36:43 +0900354 depends on X86_32 && !STACKPROTECTOR
Tejun Heoccbeed32009-02-09 22:17:40 +0900355
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530356config ARCH_SUPPORTS_UPROBES
357 def_bool y
358
Rob Herringd20642f2014-04-18 17:19:54 -0500359config FIX_EARLYCON_MEM
360 def_bool y
361
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +0300362config DYNAMIC_PHYSICAL_MASK
363 bool
364
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700365config PGTABLE_LEVELS
366 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300367 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700368 default 4 if X86_64
369 default 3 if X86_PAE
370 default 2
371
Masahiro Yamada2a61f472018-05-28 18:22:00 +0900372config CC_HAS_SANE_STACKPROTECTOR
373 bool
374 default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
375 default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
376 help
377 We have to make sure stack protector is unconditionally disabled if
378 the compiler produces broken code.
379
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100380menu "Processor type and features"
381
Randy Dunlap5ee71532012-01-16 11:57:18 -0800382config ZONE_DMA
383 bool "DMA memory allocation support" if EXPERT
384 default y
385 help
386 DMA memory allocation support allows devices with less than 32-bit
387 addressing to allocate within the first 16MB of address space.
388 Disable if no such devices will be used.
389
390 If unsure, say Y.
391
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100392config SMP
393 bool "Symmetric multi-processing support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900394 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100395 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800396 a system with only one CPU, say N. If you have a system with more
397 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100398
Robert Graffham4a474152014-01-23 15:55:29 -0800399 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100400 machines, but will use only one CPU of a multiprocessor machine. If
401 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800402 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100403 will run faster if you say N here.
404
405 Note that if you say Y here and choose architecture "586" or
406 "Pentium" under "Processor family", the kernel will not work on 486
407 architectures. Similarly, multiprocessor kernels for the "PPro"
408 architecture may not work on all Pentium based boards.
409
410 People using multiprocessor machines who say Y here should also say
411 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
412 Management" code will be disabled if you say Y here.
413
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -0300414 See also <file:Documentation/x86/i386/IO-APIC.rst>,
Mauro Carvalho Chehab4f4cfa62019-06-27 14:56:51 -0300415 <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100416 <http://www.tldp.org/docs.html#howto>.
417
418 If you don't know what to do here, say N.
419
Josh Triplett9def39be2013-10-30 08:09:45 -0700420config X86_FEATURE_NAMES
421 bool "Processor feature human-readable names" if EMBEDDED
422 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900423 help
Josh Triplett9def39be2013-10-30 08:09:45 -0700424 This option compiles in a table of x86 feature bits and corresponding
425 names. This is required to support /proc/cpuinfo and a few kernel
426 messages. You can disable this to save space, at the expense of
427 making those few kernel messages show numeric feature bits instead.
428
429 If in doubt, say Y.
430
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800431config X86_X2APIC
432 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200433 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900434 help
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800435 This enables x2apic support on CPUs that have this feature.
436
437 This allows 32-bit apic IDs (so it can support very large systems),
438 and accesses the local apic via MSRs not via mmio.
439
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800440 If you don't know what to do here, say N.
441
Yinghai Lu6695c852008-06-19 12:13:09 -0700442config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700443 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000444 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200445 depends on X86_LOCAL_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900446 help
Yinghai Lu6695c852008-06-19 12:13:09 -0700447 For old smp systems that do not have proper acpi support. Newer systems
448 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700449
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000450config GOLDFISH
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +0100451 def_bool y
452 depends on X86_GOLDFISH
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000453
David Woodhouse76b04382018-01-11 21:46:25 +0000454config RETPOLINE
455 bool "Avoid speculative indirect branches in kernel"
456 default y
457 help
458 Compile kernel with the retpoline compiler options to guard against
459 kernel-to-user data leaks by avoiding speculative indirect
460 branches. Requires a compiler with -mindirect-branch=thunk-extern
461 support for full protection. The kernel may run slower.
462
Johannes Weinere6d42932019-01-29 17:44:36 -0500463config X86_CPU_RESCTRL
464 bool "x86 CPU resource control support"
Babu Moger6fe07ce2018-11-21 20:28:39 +0000465 depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100466 select KERNFS
Chen Yue79f15a2020-01-15 17:28:51 +0800467 select PROC_CPU_RESCTRL if PROC_FS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700468 help
Johannes Weinere6d42932019-01-29 17:44:36 -0500469 Enable x86 CPU resource control support.
Babu Moger6fe07ce2018-11-21 20:28:39 +0000470
471 Provide support for the allocation and monitoring of system resources
472 usage by the CPU.
473
474 Intel calls this Intel Resource Director Technology
475 (Intel(R) RDT). More information about RDT can be found in the
476 Intel x86 Architecture Software Developer Manual.
477
478 AMD calls this AMD Platform Quality of Service (AMD QoS).
479 More information about AMD QoS can be found in the AMD64 Technology
480 Platform Quality of Service Extensions manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700481
482 Say N if unsure.
483
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800484if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800485config X86_BIGSMP
486 bool "Support for big SMP systems with more than 8 CPUs"
487 depends on SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900488 help
Randy Dunlape133f6e2019-12-03 16:06:47 -0800489 This option is needed for the systems that have more than 8 CPUs.
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800490
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800491config X86_EXTENDED_PLATFORM
492 bool "Support for extended (non-PC) x86 platforms"
493 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900494 help
Ingo Molnar06ac8342009-01-27 18:11:43 +0100495 If you disable this option then the kernel will only support
496 standard PC platforms. (which covers the vast majority of
497 systems out there.)
498
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800499 If you enable this option then you'll be able to select support
500 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100501 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800502 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800503 RDC R-321x SoC
504 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200505 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200506 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100507
508 If you have one of these systems, or if you want to build a
509 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800510endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100511
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800512if X86_64
513config X86_EXTENDED_PLATFORM
514 bool "Support for extended (non-PC) x86 platforms"
515 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900516 help
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800517 If you disable this option then the kernel will only support
518 standard PC platforms. (which covers the vast majority of
519 systems out there.)
520
521 If you enable this option then you'll be able to select support
522 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800523 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800524 ScaleMP vSMP
525 SGI Ultraviolet
526
527 If you have one of these systems, or if you want to build a
528 generic distribution kernel, say Y here - otherwise say N.
529endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800530# This is an alphabetically sorted list of 64 bit extended platforms
531# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800532config X86_NUMACHIP
533 bool "Numascale NumaChip"
534 depends on X86_64
535 depends on X86_EXTENDED_PLATFORM
536 depends on NUMA
537 depends on SMP
538 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700539 depends on PCI_MMCONFIG
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900540 help
Steffen Persvold44b111b52011-12-06 00:07:26 +0800541 Adds support for Numascale NumaChip large-SMP systems. Needed to
542 enable more than ~168 cores.
543 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100544
Ingo Molnar6a485652009-01-27 18:29:13 +0100545config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800546 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100547 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100548 select PARAVIRT
549 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800550 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300551 depends on SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900552 help
Ingo Molnar6a485652009-01-27 18:29:13 +0100553 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
554 supposed to run on these EM64T-based machines. Only choose this option
555 if you have one of these machines.
556
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800557config X86_UV
558 bool "SGI Ultraviolet"
559 depends on X86_64
560 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500561 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800562 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700563 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200564 depends on PCI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900565 help
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800566 This option is needed in order to support SGI Ultraviolet systems.
567 If you don't have one of these, you should say N here.
568
569# Following is an alphabetically sorted list of 32 bit extended platforms
570# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100571
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000572config X86_GOLDFISH
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +0100573 bool "Goldfish (Virtual Platform)"
574 depends on X86_EXTENDED_PLATFORM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900575 help
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000576 Enable support for the Goldfish virtual platform used primarily
577 for Android development. Unless you are building for the Android
578 Goldfish emulator say N here.
579
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800580config X86_INTEL_CE
581 bool "CE4100 TV platform"
582 depends on PCI
583 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800584 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800585 depends on X86_32
586 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800587 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100588 select OF
589 select OF_EARLY_FLATTREE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900590 help
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800591 Select for the Intel CE media processor (CE4100) SOC.
592 This option compiles in support for the CE4100 SOC for settop
593 boxes and media devices.
594
David Cohen4cb9b002013-12-16 17:37:26 -0800595config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100596 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100597 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800598 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000599 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200600 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000601 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000602 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800603 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000604 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000605 select APB_TIMER
Mika Westerberg54b34aa2020-04-16 11:15:33 +0300606 select INTEL_SCU_PCI
Mika Westerberg15a713d2012-01-26 17:35:05 +0000607 select MFD_INTEL_MSIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900608 help
David Cohen4cb9b002013-12-16 17:37:26 -0800609 Select to build a kernel capable of supporting Intel MID (Mobile
610 Internet Device) platform systems which do not have the PCI legacy
611 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000612
David Cohen4cb9b002013-12-16 17:37:26 -0800613 Intel MID platforms are based on an Intel processor and chipset which
614 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100615
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000616config X86_INTEL_QUARK
617 bool "Intel Quark platform support"
618 depends on X86_32
619 depends on X86_EXTENDED_PLATFORM
620 depends on X86_PLATFORM_DEVICES
621 depends on X86_TSC
622 depends on PCI
623 depends on PCI_GOANY
624 depends on X86_IO_APIC
625 select IOSF_MBI
626 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200627 select COMMON_CLK
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900628 help
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000629 Select to include support for Quark X1000 SoC.
630 Say Y here if you have a Quark based system such as the Arduino
631 compatible Intel Galileo.
632
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000633config X86_INTEL_LPSS
634 bool "Intel Low Power Subsystem Support"
Sinan Kaya5962dd22019-01-02 18:10:37 +0000635 depends on X86 && ACPI && PCI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000636 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300637 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100638 select IOSF_MBI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900639 help
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000640 Select to build support for Intel Low Power Subsystem such as
641 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300642 things like clock tree (common clock framework) and pincontrol
643 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000644
Ken Xue92082a82015-02-06 08:27:51 +0800645config X86_AMD_PLATFORM_DEVICE
646 bool "AMD ACPI2Platform devices support"
647 depends on ACPI
648 select COMMON_CLK
649 select PINCTRL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900650 help
Ken Xue92082a82015-02-06 08:27:51 +0800651 Select to interpret AMD specific ACPI device to platform device
652 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
653 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
654 implemented under PINCTRL subsystem.
655
David E. Boxced3ce72014-09-17 22:13:50 -0700656config IOSF_MBI
657 tristate "Intel SoC IOSF Sideband support for SoC platforms"
658 depends on PCI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900659 help
David E. Boxced3ce72014-09-17 22:13:50 -0700660 This option enables sideband register access support for Intel SoC
661 platforms. On these platforms the IOSF sideband is used in lieu of
662 MSR's for some register accesses, mostly but not limited to thermal
663 and power. Drivers may query the availability of this device to
664 determine if they need the sideband in order to work on these
665 platforms. The sideband is available on the following SoC products.
666 This list is not meant to be exclusive.
667 - BayTrail
668 - Braswell
669 - Quark
670
671 You should say Y if you are running a kernel on one of these SoC's.
672
David E. Boxed2226b2014-09-17 22:13:51 -0700673config IOSF_MBI_DEBUG
674 bool "Enable IOSF sideband access through debugfs"
675 depends on IOSF_MBI && DEBUG_FS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900676 help
David E. Boxed2226b2014-09-17 22:13:51 -0700677 Select this option to expose the IOSF sideband access registers (MCR,
678 MDR, MCRX) through debugfs to write and read register information from
679 different units on the SoC. This is most useful for obtaining device
680 state information for debug and analysis. As this is a general access
681 mechanism, users of this option would have specific knowledge of the
682 device they want to access.
683
684 If you don't require the option or are in doubt, say N.
685
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800686config X86_RDC321X
687 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100688 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800689 depends on X86_EXTENDED_PLATFORM
690 select M486
691 select X86_REBOOTFIXUPS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900692 help
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800693 This option is needed for RDC R-321x system-on-chip, also known
694 as R-8610-(G).
695 If you don't have one of these chips, you should say N here.
696
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100697config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100698 bool "Support non-standard 32-bit SMP architectures"
699 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800700 depends on X86_EXTENDED_PLATFORM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900701 help
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800702 This option compiles in the bigsmp and STA2X11 default
703 subarchitectures. It is intended for a generic binary
704 kernel. If you select them all, kernel will probe it one by
705 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700706
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800707# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700708
Linus Torvaldsd949f362009-09-26 09:35:07 -0700709config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100710 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700711 # MCE code calls memory_failure():
712 depends on X86_MCE
713 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700714 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
715 depends on X86_64 || !SPARSEMEM
716 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700717
Alessandro Rubini83125a32012-04-04 19:40:21 +0200718config STA2X11
719 bool "STA2X11 Companion Chip Support"
720 depends on X86_32_NON_STANDARD && PCI
Alessandro Rubini83125a32012-04-04 19:40:21 +0200721 select SWIOTLB
722 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200723 select GPIOLIB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900724 help
Alessandro Rubini83125a32012-04-04 19:40:21 +0200725 This adds support for boards based on the STA2X11 IO-Hub,
726 a.k.a. "ConneXt". The chip is used in place of the standard
727 PC chipset, so all "standard" peripherals are missing. If this
728 option is selected the kernel will still be able to boot on
729 standard PC machines.
730
Shérab82148d12010-09-25 06:06:57 +0200731config X86_32_IRIS
732 tristate "Eurobraille/Iris poweroff module"
733 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900734 help
Shérab82148d12010-09-25 06:06:57 +0200735 The Iris machines from EuroBraille do not have APM or ACPI support
736 to shut themselves down properly. A special I/O sequence is
737 needed to do so, which is what this module does at
738 kernel shutdown.
739
740 This is only for Iris machines from EuroBraille.
741
742 If unused, say N.
743
Ingo Molnarae1e9132008-11-11 09:05:16 +0100744config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100745 def_bool y
746 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800747 depends on X86
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900748 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100749 Calculate simpler /proc/<PID>/wchan values. If this option
750 is disabled then wchan values will recurse back to the
751 caller function. This provides more accurate wchan values,
752 at the expense of slightly more scheduling overhead.
753
754 If in doubt, say "Y".
755
Borislav Petkov6276a072013-03-04 21:20:21 +0100756menuconfig HYPERVISOR_GUEST
757 bool "Linux guest support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900758 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100759 Say Y here to enable options for running Linux under various hyper-
760 visors. This option enables basic hypervisor detection and platform
761 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100762
Borislav Petkov6276a072013-03-04 21:20:21 +0100763 If you say N, all options in this submenu will be skipped and
764 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100765
Borislav Petkov6276a072013-03-04 21:20:21 +0100766if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100767
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100768config PARAVIRT
769 bool "Enable paravirtualization code"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900770 help
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100771 This changes the kernel so it can modify itself when it is run
772 under a hypervisor, potentially improving performance significantly
773 over full virtualization. However, when run without a hypervisor
774 the kernel is theoretically slower and slightly larger.
775
Juergen Grossc00a2802018-08-28 09:40:21 +0200776config PARAVIRT_XXL
777 bool
778
Borislav Petkov6276a072013-03-04 21:20:21 +0100779config PARAVIRT_DEBUG
780 bool "paravirt-ops debugging"
781 depends on PARAVIRT && DEBUG_KERNEL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900782 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100783 Enable to debug paravirt_ops internals. Specifically, BUG if
784 a paravirt_op is missing when it is called.
785
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700786config PARAVIRT_SPINLOCKS
787 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700788 depends on PARAVIRT && SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900789 help
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700790 Paravirtualized spinlocks allow a pvops backend to replace the
791 spinlock implementation with something virtualization-friendly
792 (for example, block the virtual CPU rather than spinning).
793
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530794 It has a minimal impact on native kernels and gives a nice performance
795 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700796
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530797 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700798
Zhao Yakuiecca25022019-04-30 11:45:23 +0800799config X86_HV_CALLBACK_VECTOR
800 def_bool n
801
Borislav Petkov6276a072013-03-04 21:20:21 +0100802source "arch/x86/xen/Kconfig"
803
804config KVM_GUEST
805 bool "KVM Guest support (including kvmclock)"
806 depends on PARAVIRT
807 select PARAVIRT_CLOCK
Marcelo Tosattia1c44232019-07-03 20:51:29 -0300808 select ARCH_CPUIDLE_HALTPOLL
Vitaly Kuznetsovb1d40572020-05-25 16:41:23 +0200809 select X86_HV_CALLBACK_VECTOR
Borislav Petkov6276a072013-03-04 21:20:21 +0100810 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900811 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100812 This option enables various optimizations for running under the KVM
813 hypervisor. It includes a paravirtualized clock, so that instead
814 of relying on a PIT (or probably other) emulation by the
815 underlying device model, the host provides the guest with
816 timing infrastructure such as time of day, and system time
817
Marcelo Tosattia1c44232019-07-03 20:51:29 -0300818config ARCH_CPUIDLE_HALTPOLL
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +0100819 def_bool n
820 prompt "Disable host haltpoll when loading haltpoll driver"
821 help
Marcelo Tosattia1c44232019-07-03 20:51:29 -0300822 If virtualized under KVM, disable host haltpoll.
823
Maran Wilson77336072018-12-10 11:07:28 -0800824config PVH
825 bool "Support for running PVH guests"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900826 help
Maran Wilson77336072018-12-10 11:07:28 -0800827 This option enables the PVH entry point for guest virtual machines
828 as specified in the x86/HVM direct boot ABI.
829
Borislav Petkov6276a072013-03-04 21:20:21 +0100830config PARAVIRT_TIME_ACCOUNTING
831 bool "Paravirtual steal time accounting"
832 depends on PARAVIRT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900833 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100834 Select this option to enable fine granularity task steal time
835 accounting. Time spent executing other tasks in parallel with
836 the current vCPU is discounted from the vCPU power. To account for
837 that, there can be a small performance impact.
838
839 If in doubt, say N here.
840
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200841config PARAVIRT_CLOCK
842 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200843
Jan Kiszka4a362602017-11-27 09:11:46 +0100844config JAILHOUSE_GUEST
845 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100846 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100847 select X86_PM_TIMER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900848 help
Jan Kiszka4a362602017-11-27 09:11:46 +0100849 This option allows to run Linux as guest in a Jailhouse non-root
850 cell. You can leave this option disabled if you only want to start
851 Jailhouse and run Linux afterwards in the root cell.
852
Zhao Yakuiec7972c2019-04-30 11:45:24 +0800853config ACRN_GUEST
854 bool "ACRN Guest support"
855 depends on X86_64
Zhao Yakui498ad392019-04-30 11:45:25 +0800856 select X86_HV_CALLBACK_VECTOR
Zhao Yakuiec7972c2019-04-30 11:45:24 +0800857 help
858 This option allows to run Linux as guest in the ACRN hypervisor. ACRN is
859 a flexible, lightweight reference open-source hypervisor, built with
860 real-time and safety-criticality in mind. It is built for embedded
861 IOT with small footprint and real-time features. More details can be
862 found in https://projectacrn.org/.
863
Borislav Petkov6276a072013-03-04 21:20:21 +0100864endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400865
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100866source "arch/x86/Kconfig.cpu"
867
868config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100869 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100870 prompt "HPET Timer Support" if X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900871 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100872 Use the IA-PC HPET (High Precision Event Timer) to manage
873 time in preference to the PIT and RTC, if a HPET is
874 present.
875 HPET is the next generation timer replacing legacy 8254s.
876 The HPET provides a stable time base on SMP
877 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200878 as it is off-chip. The interface used is documented
879 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100880
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100881 You can safely choose Y here. However, HPET will only be
882 activated if the platform and the BIOS support this feature.
883 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100884
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100885 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100886
887config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100888 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800889 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100890
Jacob Panbb24c472009-09-02 07:37:17 -0700891config APB_TIMER
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +0100892 def_bool y if X86_INTEL_MID
893 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
894 select DW_APB_TIMER
895 depends on X86_INTEL_MID && SFI
896 help
897 APB timer is the replacement for 8254, HPET on X86 MID platforms.
898 The APBT provides a stable time base on SMP
899 systems, unlike the TSC, but it is more expensive to access,
900 as it is off-chip. APB timers are always running regardless of CPU
901 C states, they are used as per CPU clockevent device when possible.
Jacob Panbb24c472009-09-02 07:37:17 -0700902
David Rientjes6a108a12011-01-20 14:44:16 -0800903# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100904# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700905config DMI
906 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800907 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800908 bool "Enable DMI scanning" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900909 help
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700910 Enabled scanning of DMI to identify machine quirks. Say Y
911 here unless you have verified that your setup is not
912 affected by entries in the DMI blacklist. Required by PNP
913 BIOS code.
914
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100915config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700916 bool "Old AMD GART IOMMU support"
Christoph Hellwig2f9237d2020-07-08 09:30:00 +0200917 select DMA_OPS
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200918 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100919 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200920 depends on X86_64 && PCI && AMD_NB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900921 help
Ingo Molnarced3c422013-10-06 11:45:20 +0200922 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
923 GART based hardware IOMMUs.
924
925 The GART supports full DMA access for devices with 32-bit access
926 limitations, on systems with more than 3 GB. This is usually needed
927 for USB, sound, many IDE/SATA chipsets and some other devices.
928
929 Newer systems typically have a modern AMD IOMMU, supported via
930 the CONFIG_AMD_IOMMU=y config option.
931
932 In normal configurations this driver is only active when needed:
933 there's more than 3 GB of memory and the system contains a
934 32-bit limited device.
935
936 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100937
Mike Travis1184dc22008-05-12 21:21:12 +0200938config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200939 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700940 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800941 select CPUMASK_OFFSTACK
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900942 help
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200943 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200944 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100945
Ingo Molnaraec64872018-02-10 12:36:29 +0100946#
947# The maximum number of CPUs supported:
948#
949# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
950# and which can be configured interactively in the
951# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
952#
953# The ranges are different on 32-bit and 64-bit kernels, depending on
954# hardware capabilities and scalability features of the kernel.
955#
956# ( If MAXSMP is enabled we just use the highest possible value and disable
957# interactive configuration. )
958#
959
960config NR_CPUS_RANGE_BEGIN
961 int
962 default NR_CPUS_RANGE_END if MAXSMP
963 default 1 if !SMP
964 default 2
965
966config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800967 int
968 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100969 default 64 if SMP && X86_BIGSMP
970 default 8 if SMP && !X86_BIGSMP
971 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800972
Ingo Molnaraec64872018-02-10 12:36:29 +0100973config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800974 int
975 depends on X86_64
Scott Wood1edae1a2019-10-12 02:00:54 -0500976 default 8192 if SMP && CPUMASK_OFFSTACK
977 default 512 if SMP && !CPUMASK_OFFSTACK
Ingo Molnaraec64872018-02-10 12:36:29 +0100978 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800979
Ingo Molnaraec64872018-02-10 12:36:29 +0100980config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800981 int
982 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100983 default 32 if X86_BIGSMP
984 default 8 if SMP
985 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800986
Ingo Molnaraec64872018-02-10 12:36:29 +0100987config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800988 int
989 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100990 default 8192 if MAXSMP
991 default 64 if SMP
992 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800993
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100994config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800995 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +0100996 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
997 default NR_CPUS_DEFAULT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900998 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100999 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -05001000 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +03001001 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001002 minimum value which makes sense is 2.
1003
Ingo Molnaraec64872018-02-10 12:36:29 +01001004 This is purely to save memory: each supported CPU adds about 8KB
1005 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001006
1007config SCHED_SMT
Thomas Gleixnerdbe73362018-11-25 19:33:37 +01001008 def_bool y if SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001009
1010config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001011 def_bool y
1012 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001013 depends on SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001014 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001015 Multi-core scheduler support improves the CPU scheduler's decision
1016 making when dealing with multi-core CPU chips at a cost of slightly
1017 increased overhead in some places. If unsure say N here.
1018
Tim Chende966cf2016-11-29 10:43:27 -08001019config SCHED_MC_PRIO
1020 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001021 depends on SCHED_MC && CPU_SUP_INTEL
1022 select X86_INTEL_PSTATE
1023 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001024 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001025 help
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001026 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1027 core ordering determined at manufacturing time, which allows
1028 certain cores to reach higher turbo frequencies (when running
1029 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001030
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001031 Enabling this kernel feature teaches the scheduler about
1032 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1033 scheduler's CPU selection logic accordingly, so that higher
1034 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001035
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001036 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001037
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001038 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001039
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001040config UP_LATE_INIT
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001041 def_bool y
1042 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001043
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001044config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001045 bool "Local APIC support on uniprocessors" if !PCI_MSI
1046 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001047 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001048 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001049 A local APIC (Advanced Programmable Interrupt Controller) is an
1050 integrated interrupt controller in the CPU. If you have a single-CPU
1051 system which has a processor with a local APIC, you can say Y here to
1052 enable and use it. If you say Y here even though your machine doesn't
1053 have a local APIC, then the kernel will still run with no slowdown at
1054 all. The local APIC supports CPU-generated self-interrupts (timer,
1055 performance counters), and the NMI watchdog which detects hard
1056 lockups.
1057
1058config X86_UP_IOAPIC
1059 bool "IO-APIC support on uniprocessors"
1060 depends on X86_UP_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001061 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001062 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1063 SMP-capable replacement for PC-style interrupt controllers. Most
1064 SMP systems and many recent uniprocessor systems have one.
1065
1066 If you have a single-CPU system with an IO-APIC, you can say Y here
1067 to use it. If you say Y here even though your machine doesn't have
1068 an IO-APIC, then the kernel will still run with no slowdown at all.
1069
1070config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001071 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001072 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001073 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001074 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001075
1076config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001077 def_bool y
1078 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001079
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001080config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1081 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001082 depends on X86_IO_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001083 help
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001084 This option enables a workaround that fixes a source of
1085 spurious interrupts. This is recommended when threaded
1086 interrupt handling is used on systems where the generation of
1087 superfluous "boot interrupts" cannot be disabled.
1088
1089 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1090 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1091 kernel does during interrupt handling). On chipsets where this
1092 boot IRQ generation cannot be disabled, this workaround keeps
1093 the original IRQ line masked so that only the equivalent "boot
1094 IRQ" is delivered to the CPUs. The workaround also tells the
1095 kernel to set up the IRQ handler on the boot IRQ line. In this
1096 way only one interrupt is delivered to the kernel. Otherwise
1097 the spurious second interrupt may cause the kernel to bring
1098 down (vital) interrupt lines.
1099
1100 Only affects "broken" chipsets. Interrupt sharing may be
1101 increased on these systems.
1102
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001103config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001104 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001105 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001106 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001107 help
Andi Kleenbab9bc62009-07-09 00:31:38 +02001108 Machine Check support allows the processor to notify the
1109 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001110 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001111 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001112
Tony Luck5de97c92017-03-27 11:33:03 +02001113config X86_MCELOG_LEGACY
1114 bool "Support for deprecated /dev/mcelog character device"
1115 depends on X86_MCE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001116 help
Tony Luck5de97c92017-03-27 11:33:03 +02001117 Enable support for /dev/mcelog which is needed by the old mcelog
1118 userspace logging daemon. Consider switching to the new generation
1119 rasdaemon solution.
1120
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001121config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001122 def_bool y
1123 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001124 depends on X86_MCE && X86_LOCAL_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001125 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001126 Additional support for intel specific MCE features such as
1127 the thermal monitor.
1128
1129config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001130 def_bool y
1131 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001132 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001133 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001134 Additional support for AMD specific MCE features such as
1135 the DRAM Error Threshold.
1136
Andi Kleen4efc0672009-04-28 19:07:31 +02001137config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001138 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001139 depends on X86_32 && X86_MCE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001140 help
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001141 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001142 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001143 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001144
Andi Kleenb2762682009-02-12 13:49:31 +01001145config X86_MCE_THRESHOLD
1146 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001147 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001148
Andi Kleenea149b32009-04-29 19:31:00 +02001149config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001150 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001151 tristate "Machine check injector support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001152 help
Andi Kleenea149b32009-04-29 19:31:00 +02001153 Provide support for injecting machine checks for testing purposes.
1154 If you don't know what a machine check is and you don't do kernel
1155 QA it is safe to say n.
1156
Andi Kleen4efc0672009-04-28 19:07:31 +02001157config X86_THERMAL_VECTOR
1158 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001159 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001160
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001161source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001162
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001163config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001164 bool "Legacy VM86 support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001165 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001166 help
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001167 This option allows user programs to put the CPU into V8086
1168 mode, which is an 80286-era approximation of 16-bit real mode.
1169
1170 Some very old versions of X and/or vbetool require this option
1171 for user mode setting. Similarly, DOSEMU will use it if
1172 available to accelerate real mode DOS programs. However, any
1173 recent version of DOSEMU, X, or vbetool should be fully
1174 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001175 fall back to software emulation. Nevertheless, if you are using
1176 a 16-bit DOS program where 16-bit performance matters, vm86
1177 mode might be faster than emulation and you might want to
1178 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001179
Ingo Molnar1e642812015-09-05 08:58:10 +02001180 Note that any app that works on a 64-bit kernel is unlikely to
1181 need this option, as 64-bit kernels don't, and can't, support
1182 V8086 mode. This option is also unrelated to 16-bit protected
1183 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001184
Ingo Molnar1e642812015-09-05 08:58:10 +02001185 Enabling this option increases the complexity of the kernel
1186 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001187
Ingo Molnar1e642812015-09-05 08:58:10 +02001188 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001189
1190config VM86
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001191 bool
1192 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001193
1194config X86_16BIT
1195 bool "Enable support for 16-bit segments" if EXPERT
1196 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001197 depends on MODIFY_LDT_SYSCALL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001198 help
H. Peter Anvin34273f42014-05-04 10:36:22 -07001199 This option is required by programs like Wine to run 16-bit
1200 protected mode legacy code on x86 processors. Disabling
1201 this option saves about 300 bytes on i386, or around 6K text
1202 plus 16K runtime memory on x86-64,
1203
1204config X86_ESPFIX32
1205 def_bool y
1206 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001207
H. Peter Anvin197725d2014-05-04 10:00:49 -07001208config X86_ESPFIX64
1209 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001210 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001211
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001212config X86_VSYSCALL_EMULATION
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001213 bool "Enable vsyscall emulation" if EXPERT
1214 default y
1215 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001216 help
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001217 This enables emulation of the legacy vsyscall page. Disabling
1218 it is roughly equivalent to booting with vsyscall=none, except
1219 that it will also disable the helpful warning if a program
1220 tries to use a vsyscall. With this option set to N, offending
1221 programs will just segfault, citing addresses of the form
1222 0xffffffffff600?00.
1223
1224 This option is required by many programs built before 2013, and
1225 care should be used even with newer programs if set to N.
1226
1227 Disabling this option saves about 7K of kernel size and
1228 possibly 4K of additional runtime pagetable memory.
1229
Thomas Gleixner111e7b12019-11-12 21:40:33 +01001230config X86_IOPL_IOPERM
1231 bool "IOPERM and IOPL Emulation"
Thomas Gleixnera24ca992019-11-11 23:03:29 +01001232 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001233 help
Thomas Gleixner111e7b12019-11-12 21:40:33 +01001234 This enables the ioperm() and iopl() syscalls which are necessary
1235 for legacy applications.
1236
Thomas Gleixnerc8137ac2019-11-11 23:03:28 +01001237 Legacy IOPL support is an overbroad mechanism which allows user
1238 space aside of accessing all 65536 I/O ports also to disable
1239 interrupts. To gain this access the caller needs CAP_SYS_RAWIO
1240 capabilities and permission from potentially active security
1241 modules.
1242
1243 The emulation restricts the functionality of the syscall to
1244 only allowing the full range I/O port access, but prevents the
Thomas Gleixnera24ca992019-11-11 23:03:29 +01001245 ability to disable interrupts from user space which would be
1246 granted if the hardware IOPL mechanism would be used.
Thomas Gleixnerc8137ac2019-11-11 23:03:28 +01001247
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001248config TOSHIBA
1249 tristate "Toshiba Laptop support"
1250 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001251 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001252 This adds a driver to safely access the System Management Mode of
1253 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1254 not work on models with a Phoenix BIOS. The System Management Mode
1255 is used to set the BIOS and power saving options on Toshiba portables.
1256
1257 For information on utilities to make use of this driver see the
1258 Toshiba Linux utilities web site at:
1259 <http://www.buzzard.org.uk/toshiba/>.
1260
1261 Say Y if you intend to run this kernel on a Toshiba portable.
1262 Say N otherwise.
1263
1264config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001265 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001266 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001267 select SENSORS_DELL_SMM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001268 help
Pali Rohár039ae582015-05-14 13:16:37 +02001269 This option enables legacy /proc/i8k userspace interface in hwmon
1270 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1271 temperature and allows controlling fan speeds of Dell laptops via
1272 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1273 it reports also power and hotkey status. For fan speed control is
1274 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001275
Pali Rohár039ae582015-05-14 13:16:37 +02001276 Say Y if you intend to run this kernel on old Dell laptops or want to
1277 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001278 Say N otherwise.
1279
1280config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001281 bool "Enable X86 board specific fixups for reboot"
1282 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001283 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001284 This enables chipset and/or board specific fixups to be done
1285 in order to get reboot to work correctly. This is only needed on
1286 some combinations of hardware and BIOS. The symptom, for which
1287 this config is intended, is when reboot ends with a stalled/hung
1288 system.
1289
1290 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001291 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001292
1293 Say Y if you want to enable the fixup. Currently, it's safe to
1294 enable this option even if you don't need it.
1295 Say N otherwise.
1296
1297config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001298 bool "CPU microcode loading support"
1299 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001300 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001301 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001302 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001303 Intel and AMD processors. The Intel support is for the IA32 family,
1304 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1305 AMD support is for families 0x10 and later. You will obviously need
1306 the actual microcode binary data itself which is not shipped with
1307 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001308
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001309 The preferred method to load microcode from a detached initrd is described
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001310 in Documentation/x86/microcode.rst. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001311 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1312 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001313
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001314 In addition, you can build the microcode into the kernel. For that you
1315 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1316 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001317
Peter Oruba8d86f392008-07-28 18:44:21 +02001318config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001319 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001320 depends on MICROCODE
1321 default MICROCODE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001322 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001323 This options enables microcode patch loading support for Intel
1324 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001325
Alanb8989db2014-01-20 18:01:56 +00001326 For the current Intel microcode data package go to
1327 <https://downloadcenter.intel.com> and search for
1328 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001329
Peter Oruba80cc9f12008-07-28 18:44:22 +02001330config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001331 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001332 depends on MICROCODE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001333 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001334 If you select this option, microcode patch loading support for AMD
1335 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001336
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001337config MICROCODE_OLD_INTERFACE
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001338 bool "Ancient loading interface (DEPRECATED)"
1339 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001340 depends on MICROCODE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001341 help
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001342 DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface
1343 which was used by userspace tools like iucode_tool and microcode.ctl.
1344 It is inadequate because it runs too late to be able to properly
1345 load microcode on a machine and it needs special tools. Instead, you
1346 should've switched to the early loading method with the initrd or
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001347 builtin microcode by now: Documentation/x86/microcode.rst
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001348
1349config X86_MSR
1350 tristate "/dev/cpu/*/msr - Model-specific register support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001351 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001352 This device gives privileged processes access to the x86
1353 Model-Specific Registers (MSRs). It is a character device with
1354 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1355 MSR accesses are directed to a specific CPU on multi-processor
1356 systems.
1357
1358config X86_CPUID
1359 tristate "/dev/cpu/*/cpuid - CPU information support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001360 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001361 This device gives processes access to the x86 CPUID instruction to
1362 be executed on a specific processor. It is a character device
1363 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1364 /dev/cpu/31/cpuid.
1365
1366choice
1367 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001368 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001369 depends on X86_32
1370
1371config NOHIGHMEM
1372 bool "off"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001373 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001374 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1375 However, the address space of 32-bit x86 processors is only 4
1376 Gigabytes large. That means that, if you have a large amount of
1377 physical memory, not all of it can be "permanently mapped" by the
1378 kernel. The physical memory that's not permanently mapped is called
1379 "high memory".
1380
1381 If you are compiling a kernel which will never run on a machine with
1382 more than 1 Gigabyte total physical RAM, answer "off" here (default
1383 choice and suitable for most users). This will result in a "3GB/1GB"
1384 split: 3GB are mapped so that each process sees a 3GB virtual memory
1385 space and the remaining part of the 4GB virtual memory space is used
1386 by the kernel to permanently map as much physical memory as
1387 possible.
1388
1389 If the machine has between 1 and 4 Gigabytes physical RAM, then
1390 answer "4GB" here.
1391
1392 If more than 4 Gigabytes is used then answer "64GB" here. This
1393 selection turns Intel PAE (Physical Address Extension) mode on.
1394 PAE implements 3-level paging on IA32 processors. PAE is fully
1395 supported by Linux, PAE mode is implemented on all recent Intel
1396 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1397 then the kernel will not boot on CPUs that don't support PAE!
1398
1399 The actual amount of total physical memory will either be
1400 auto detected or can be forced by using a kernel command line option
1401 such as "mem=256M". (Try "man bootparam" or see the documentation of
1402 your boot loader (lilo or loadlin) about how to pass options to the
1403 kernel at boot time.)
1404
1405 If unsure, say "off".
1406
1407config HIGHMEM4G
1408 bool "4GB"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001409 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001410 Select this if you have a 32-bit processor and between 1 and 4
1411 gigabytes of physical RAM.
1412
1413config HIGHMEM64G
1414 bool "64GB"
Matthew Whitehead69b8d3f2018-02-15 11:54:55 -05001415 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001416 select X86_PAE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001417 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001418 Select this if you have a 32-bit processor and more than 4
1419 gigabytes of physical RAM.
1420
1421endchoice
1422
1423choice
David Rientjes6a108a12011-01-20 14:44:16 -08001424 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001425 default VMSPLIT_3G
1426 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001427 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001428 Select the desired split between kernel and user memory.
1429
1430 If the address range available to the kernel is less than the
1431 physical memory installed, the remaining memory will be available
1432 as "high memory". Accessing high memory is a little more costly
1433 than low memory, as it needs to be mapped into the kernel first.
1434 Note that increasing the kernel address space limits the range
1435 available to user programs, making the address space there
1436 tighter. Selecting anything other than the default 3G/1G split
1437 will also likely make your kernel incompatible with binary-only
1438 kernel modules.
1439
1440 If you are not absolutely sure what you are doing, leave this
1441 option alone!
1442
1443 config VMSPLIT_3G
1444 bool "3G/1G user/kernel split"
1445 config VMSPLIT_3G_OPT
1446 depends on !X86_PAE
1447 bool "3G/1G user/kernel split (for full 1G low memory)"
1448 config VMSPLIT_2G
1449 bool "2G/2G user/kernel split"
1450 config VMSPLIT_2G_OPT
1451 depends on !X86_PAE
1452 bool "2G/2G user/kernel split (for full 2G low memory)"
1453 config VMSPLIT_1G
1454 bool "1G/3G user/kernel split"
1455endchoice
1456
1457config PAGE_OFFSET
1458 hex
1459 default 0xB0000000 if VMSPLIT_3G_OPT
1460 default 0x80000000 if VMSPLIT_2G
1461 default 0x78000000 if VMSPLIT_2G_OPT
1462 default 0x40000000 if VMSPLIT_1G
1463 default 0xC0000000
1464 depends on X86_32
1465
1466config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001467 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001468 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001469
1470config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001471 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001472 depends on X86_32 && !HIGHMEM4G
Christoph Hellwigd4a451d2018-04-03 16:24:20 +02001473 select PHYS_ADDR_T_64BIT
Christian Melki9d99c712015-10-05 17:31:33 +02001474 select SWIOTLB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001475 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001476 PAE is required for NX support, and furthermore enables
1477 larger swapspace support for non-overcommit purposes. It
1478 has the cost of more pagetable lookup overhead, and also
1479 consumes more pagetable space per process.
1480
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001481config X86_5LEVEL
1482 bool "Enable 5-level page tables support"
Kirill A. Shutemov18ec1ea2019-09-13 12:54:52 +03001483 default y
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001484 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001485 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001486 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001487 help
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001488 5-level paging enables access to larger address space:
1489 upto 128 PiB of virtual address space and 4 PiB of
1490 physical address space.
1491
1492 It will be supported by future Intel CPUs.
1493
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001494 A kernel with the option enabled can be booted on machines that
1495 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001496
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001497 See Documentation/x86/x86_64/5level-paging.rst for more
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001498 information.
1499
1500 Say N if unsure.
1501
Ingo Molnar10971ab2015-03-05 08:18:23 +01001502config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001503 def_bool y
Vlastimil Babka2e1da132019-08-07 15:02:58 +02001504 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001505 help
Ingo Molnar10971ab2015-03-05 08:18:23 +01001506 Certain kernel features effectively disable kernel
1507 linear 1 GB mappings (even if the CPU otherwise
1508 supports them), so don't confuse the user by printing
1509 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001510
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001511config X86_CPA_STATISTICS
1512 bool "Enable statistic for Change Page Attribute"
1513 depends on DEBUG_FS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001514 help
Ingo Molnarb75baaf2019-11-20 15:57:04 +01001515 Expose statistics about the Change Page Attribute mechanism, which
Colin Ian Kinga9432452019-04-16 11:57:51 +01001516 helps to determine the effectiveness of preserving large and huge
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001517 page mappings when mapping protections are changed.
1518
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001519config AMD_MEM_ENCRYPT
1520 bool "AMD Secure Memory Encryption (SME) support"
1521 depends on X86_64 && CPU_SUP_AMD
David Rientjes82fef0a2020-04-14 17:05:01 -07001522 select DMA_COHERENT_POOL
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +03001523 select DYNAMIC_PHYSICAL_MASK
Ard Biesheuvelce9084b2019-02-02 10:41:17 +01001524 select ARCH_USE_MEMREMAP_PROT
Tom Lendacky9087c372019-07-10 19:01:19 +00001525 select ARCH_HAS_FORCE_DMA_UNENCRYPTED
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001526 help
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001527 Say yes to enable support for the encryption of system memory.
1528 This requires an AMD processor that supports Secure Memory
1529 Encryption (SME).
1530
1531config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1532 bool "Activate AMD Secure Memory Encryption (SME) by default"
1533 default y
1534 depends on AMD_MEM_ENCRYPT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001535 help
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001536 Say yes to have system memory encrypted by default if running on
1537 an AMD processor that supports Secure Memory Encryption (SME).
1538
1539 If set to Y, then the encryption of system memory can be
1540 deactivated with the mem_encrypt=off command line option.
1541
1542 If set to N, then the encryption of system memory can be
1543 activated with the mem_encrypt=on command line option.
1544
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001545# Common NUMA Features
1546config NUMA
Randy Dunlape133f6e2019-12-03 16:06:47 -08001547 bool "NUMA Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001548 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001549 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1550 default y if X86_BIGSMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001551 help
Randy Dunlape133f6e2019-12-03 16:06:47 -08001552 Enable NUMA (Non-Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001553
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001554 The kernel will try to allocate memory used by a CPU on the
1555 local memory controller of the CPU and add some more
1556 NUMA awareness to the kernel.
1557
Ingo Molnarc280ea52008-11-08 13:29:45 +01001558 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001559 (or later), AMD Opteron, or EM64T NUMA.
1560
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001561 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001562 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001563
1564 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001565
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001566config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001567 def_bool y
1568 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001569 depends on X86_64 && NUMA && PCI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001570 help
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001571 Enable AMD NUMA node topology detection. You should say Y here if
1572 you have a multi processor AMD system. This uses an old method to
1573 read the NUMA configuration directly from the builtin Northbridge
1574 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1575 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001576
1577config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001578 def_bool y
1579 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001580 depends on X86_64 && NUMA && ACPI && PCI
1581 select ACPI_NUMA
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001582 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001583 Enable ACPI SRAT based node topology detection.
1584
1585config NUMA_EMU
1586 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001587 depends on NUMA
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001588 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001589 Enable NUMA emulation. A flat machine will be split
1590 into virtual nodes when booted with "numa=fake=N", where N is the
1591 number of nodes. This is only useful for debugging.
1592
1593config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001594 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001595 range 1 10
1596 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001597 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001598 default "3"
1599 depends on NEED_MULTIPLE_NODES
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001600 help
Mike Travis1184dc22008-05-12 21:21:12 +02001601 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001602 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001603
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001604config ARCH_FLATMEM_ENABLE
1605 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001606 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001607
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001608config ARCH_SPARSEMEM_ENABLE
1609 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001610 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001611 select SPARSEMEM_STATIC if X86_32
1612 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1613
Tejun Heo3b166512011-04-01 11:15:12 +02001614config ARCH_SPARSEMEM_DEFAULT
Mike Rapoport6ad57f72019-04-24 16:24:11 +03001615 def_bool X86_64 || (NUMA && X86_32)
Tejun Heo3b166512011-04-01 11:15:12 +02001616
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001617config ARCH_SELECT_MEMORY_MODEL
1618 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001619 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001620
1621config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001622 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001623 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001624 help
1625 This option enables a sysfs memory/probe interface for testing.
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001626 See Documentation/admin-guide/mm/memory-hotplug.rst for more information.
Toshi Kania0842b72013-07-19 11:47:48 -06001627 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001628
Tejun Heo3b166512011-04-01 11:15:12 +02001629config ARCH_PROC_KCORE_TEXT
1630 def_bool y
1631 depends on X86_64 && PROC_KCORE
1632
Avi Kivitya29815a2010-01-10 16:28:09 +02001633config ILLEGAL_POINTER_VALUE
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001634 hex
1635 default 0 if X86_32
1636 default 0xdead000000000000 if X86_64
Avi Kivitya29815a2010-01-10 16:28:09 +02001637
Dan Williams7a678322015-08-19 00:34:34 -04001638config X86_PMEM_LEGACY_DEVICE
1639 bool
1640
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001641config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001642 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001643 depends on PHYS_ADDR_T_64BIT
1644 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001645 select X86_PMEM_LEGACY_DEVICE
Dan Williams7b27a862020-02-16 12:01:16 -08001646 select NUMA_KEEP_MEMINFO if NUMA
Dan Williams9f53f9f2015-06-09 15:33:45 -04001647 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001648 help
1649 Treat memory marked using the non-standard e820 type of 12 as used
1650 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1651 The kernel will offer these regions to the 'pmem' driver so
1652 they can be used for persistent storage.
1653
1654 Say Y if unsure.
1655
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001656config HIGHPTE
1657 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001658 depends on HIGHMEM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001659 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001660 The VM uses one page table entry for each page of physical memory.
1661 For systems with a lot of RAM, this can be wasteful of precious
1662 low memory. Setting this option will put user-space page table
1663 entries in high memory.
1664
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001665config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001666 bool "Check for low memory corruption"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001667 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001668 Periodically check for memory corruption in low memory, which
1669 is suspected to be caused by BIOS. Even when enabled in the
1670 configuration, it is disabled at runtime. Enable it by
1671 setting "memory_corruption_check=1" on the kernel command
1672 line. By default it scans the low 64k of memory every 60
1673 seconds; see the memory_corruption_check_size and
1674 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001675 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001676
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001677 When enabled with the default parameters, this option has
1678 almost no overhead, as it reserves a relatively small amount
1679 of memory and scans it infrequently. It both detects corruption
1680 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001681
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001682 It is, however, intended as a diagnostic tool; if repeatable
1683 BIOS-originated corruption always affects the same memory,
1684 you can use memmap= to prevent the kernel from using that
1685 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001686
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001687config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001688 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001689 depends on X86_CHECK_BIOS_CORRUPTION
1690 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001691 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001692 Set whether the default state of memory_corruption_check is
1693 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001694
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001695config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001696 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1697 default 64
1698 range 4 640
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001699 help
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001700 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001701
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001702 The first page contains BIOS data structures that the kernel
1703 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001704
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001705 By default we reserve the first 64K of physical RAM, as a
1706 number of BIOSes are known to corrupt that memory range
1707 during events such as suspend/resume or monitor cable
1708 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001709
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001710 You can set this to 4 if you are absolutely sure that you
1711 trust the BIOS to get all its memory reservations and usages
1712 right. If you know your BIOS have problems beyond the
1713 default 64K area, you can set this to 640 to avoid using the
1714 entire low memory range.
1715
1716 If you have doubts about the BIOS (e.g. suspend/resume does
1717 not work or there's kernel crashes after certain hardware
1718 hotplug events) then you might want to enable
1719 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1720 typical corruption patterns.
1721
1722 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001723
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001724config MATH_EMULATION
1725 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001726 depends on MODIFY_LDT_SYSCALL
Arnd Bergmann87d60212019-10-01 16:23:35 +02001727 prompt "Math emulation" if X86_32 && (M486SX || MELAN)
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001728 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001729 Linux can emulate a math coprocessor (used for floating point
1730 operations) if you don't have one. 486DX and Pentium processors have
1731 a math coprocessor built in, 486SX and 386 do not, unless you added
1732 a 487DX or 387, respectively. (The messages during boot time can
1733 give you some hints here ["man dmesg"].) Everyone needs either a
1734 coprocessor or this emulation.
1735
1736 If you don't have a math coprocessor, you need to say Y here; if you
1737 say Y here even though you have a coprocessor, the coprocessor will
1738 be used nevertheless. (This behavior can be changed with the kernel
1739 command line option "no387", which comes handy if your coprocessor
1740 is broken. Try "man bootparam" or see the documentation of your boot
1741 loader (lilo or loadlin) about how to pass options to the kernel at
1742 boot time.) This means that it is a good idea to say Y here if you
1743 intend to use this kernel on different machines.
1744
1745 More information about the internals of the Linux math coprocessor
1746 emulation can be found in <file:arch/x86/math-emu/README>.
1747
1748 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1749 kernel, it won't hurt.
1750
1751config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001752 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001753 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001754 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001755 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1756 the Memory Type Range Registers (MTRRs) may be used to control
1757 processor access to memory ranges. This is most useful if you have
1758 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1759 allows bus write transfers to be combined into a larger transfer
1760 before bursting over the PCI/AGP bus. This can increase performance
1761 of image write operations 2.5 times or more. Saying Y here creates a
1762 /proc/mtrr file which may be used to manipulate your processor's
1763 MTRRs. Typically the X server should use this.
1764
1765 This code has a reasonably generic interface so that similar
1766 control registers on other processors can be easily supported
1767 as well:
1768
1769 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1770 Registers (ARRs) which provide a similar functionality to MTRRs. For
1771 these, the ARRs are used to emulate the MTRRs.
1772 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1773 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1774 write-combining. All of these processors are supported by this code
1775 and it makes sense to say Y here if you have one of them.
1776
1777 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1778 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1779 can lead to all sorts of problems, so it's good to say Y here.
1780
1781 You can safely say Y even if your machine doesn't have MTRRs, you'll
1782 just add about 9 KB to your kernel.
1783
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001784 See <file:Documentation/x86/mtrr.rst> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001785
Yinghai Lu95ffa242008-04-29 03:52:33 -07001786config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001787 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001788 prompt "MTRR cleanup support"
1789 depends on MTRR
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001790 help
Thomas Gleixneraba37282008-07-15 14:48:48 +02001791 Convert MTRR layout from continuous to discrete, so X drivers can
1792 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001793
Thomas Gleixneraba37282008-07-15 14:48:48 +02001794 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001795 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001796 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001797
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001798 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001799
1800config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001801 int "MTRR cleanup enable value (0-1)"
1802 range 0 1
1803 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001804 depends on MTRR_SANITIZER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001805 help
Yinghai Luf5098d62008-04-29 20:25:58 -07001806 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001807
Yinghai Lu12031a62008-05-02 02:40:22 -07001808config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1809 int "MTRR cleanup spare reg num (0-7)"
1810 range 0 7
1811 default "1"
1812 depends on MTRR_SANITIZER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001813 help
Yinghai Lu12031a62008-05-02 02:40:22 -07001814 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001815 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001816
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001817config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001818 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001819 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001820 depends on MTRR
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001821 help
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001822 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001823
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001824 PATs are the modern equivalents of MTRRs and are much more
1825 flexible than MTRRs.
1826
1827 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001828 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001829
1830 If unsure, say Y.
1831
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001832config ARCH_USES_PG_UNCACHED
1833 def_bool y
1834 depends on X86_PAT
1835
H. Peter Anvin628c6242011-07-31 13:59:29 -07001836config ARCH_RANDOM
1837 def_bool y
1838 prompt "x86 architectural random number generator" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001839 help
H. Peter Anvin628c6242011-07-31 13:59:29 -07001840 Enable the x86 architectural RDRAND instruction
1841 (Intel Bull Mountain technology) to generate random numbers.
1842 If supported, this is a high bandwidth, cryptographically
1843 secure hardware random number generator.
1844
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001845config X86_SMAP
1846 def_bool y
1847 prompt "Supervisor Mode Access Prevention" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001848 help
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001849 Supervisor Mode Access Prevention (SMAP) is a security
1850 feature in newer Intel processors. There is a small
1851 performance cost if this enabled and turned on; there is
1852 also a small increase in the kernel size if this is enabled.
1853
1854 If unsure, say Y.
1855
Babu Mogerb9718802019-11-05 21:25:32 +00001856config X86_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001857 def_bool y
Babu Mogerb9718802019-11-05 21:25:32 +00001858 prompt "User Mode Instruction Prevention" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001859 help
Babu Mogerb9718802019-11-05 21:25:32 +00001860 User Mode Instruction Prevention (UMIP) is a security feature in
1861 some x86 processors. If enabled, a general protection fault is
1862 issued if the SGDT, SLDT, SIDT, SMSW or STR instructions are
1863 executed in user mode. These instructions unnecessarily expose
1864 information about the hardware state.
Ricardo Neri796ebc82017-11-13 22:29:42 -08001865
1866 The vast majority of applications do not use these instructions.
1867 For the very few that do, software emulation is provided in
1868 specific cases in protected and virtual-8086 modes. Emulated
1869 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001870
Dave Hansen35e97792016-02-12 13:02:00 -08001871config X86_INTEL_MEMORY_PROTECTION_KEYS
Babu Moger38f3e772020-05-28 11:08:23 -05001872 prompt "Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001873 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001874 # Note: only available in 64-bit mode
Babu Moger38f3e772020-05-28 11:08:23 -05001875 depends on X86_64 && (CPU_SUP_INTEL || CPU_SUP_AMD)
Ingo Molnar52c8e602016-11-15 10:15:03 +01001876 select ARCH_USES_HIGH_VMA_FLAGS
1877 select ARCH_HAS_PKEYS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001878 help
Dave Hansen284244a2016-02-12 13:02:28 -08001879 Memory Protection Keys provides a mechanism for enforcing
1880 page-based protections, but without requiring modification of the
1881 page tables when an application changes protection domains.
1882
Mauro Carvalho Chehab1eecbcd2019-06-07 15:54:31 -03001883 For details, see Documentation/core-api/protection-keys.rst
Dave Hansen284244a2016-02-12 13:02:28 -08001884
1885 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001886
Michal Hockodb616172019-10-23 12:35:50 +02001887choice
1888 prompt "TSX enable mode"
1889 depends on CPU_SUP_INTEL
1890 default X86_INTEL_TSX_MODE_OFF
1891 help
1892 Intel's TSX (Transactional Synchronization Extensions) feature
1893 allows to optimize locking protocols through lock elision which
1894 can lead to a noticeable performance boost.
1895
1896 On the other hand it has been shown that TSX can be exploited
1897 to form side channel attacks (e.g. TAA) and chances are there
1898 will be more of those attacks discovered in the future.
1899
1900 Therefore TSX is not enabled by default (aka tsx=off). An admin
1901 might override this decision by tsx=on the command line parameter.
1902 Even with TSX enabled, the kernel will attempt to enable the best
1903 possible TAA mitigation setting depending on the microcode available
1904 for the particular machine.
1905
1906 This option allows to set the default tsx mode between tsx=on, =off
1907 and =auto. See Documentation/admin-guide/kernel-parameters.txt for more
1908 details.
1909
1910 Say off if not sure, auto if TSX is in use but it should be used on safe
1911 platforms or on if TSX is in use and the security aspect of tsx is not
1912 relevant.
1913
1914config X86_INTEL_TSX_MODE_OFF
1915 bool "off"
1916 help
1917 TSX is disabled if possible - equals to tsx=off command line parameter.
1918
1919config X86_INTEL_TSX_MODE_ON
1920 bool "on"
1921 help
1922 TSX is always enabled on TSX capable HW - equals the tsx=on command
1923 line parameter.
1924
1925config X86_INTEL_TSX_MODE_AUTO
1926 bool "auto"
1927 help
1928 TSX is enabled on TSX capable HW that is believed to be safe against
1929 side channel attacks- equals the tsx=auto command line parameter.
1930endchoice
1931
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001932config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001933 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001934 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001935 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001936 select EFI_RUNTIME_WRAPPERS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001937 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001938 This enables the kernel to use EFI runtime services that are
1939 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001940
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001941 This option is only useful on systems that have EFI firmware.
1942 In addition, you should use the latest ELILO loader available
1943 at <http://elilo.sourceforge.net> in order to take advantage
1944 of EFI runtime services. However, even with this option, the
1945 resultant kernel should continue to boot on existing non-EFI
1946 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001947
Matt Fleming291f3632011-12-12 21:27:52 +00001948config EFI_STUB
Ard Biesheuvel8f24f8c2019-12-24 16:10:12 +01001949 bool "EFI stub support"
1950 depends on EFI && !X86_USE_3DNOW
1951 depends on $(cc-option,-mabi=ms) || X86_32
1952 select RELOCATABLE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001953 help
Ard Biesheuvel8f24f8c2019-12-24 16:10:12 +01001954 This kernel feature allows a bzImage to be loaded directly
Matt Fleming291f3632011-12-12 21:27:52 +00001955 by EFI firmware without the use of a bootloader.
1956
Mauro Carvalho Chehab4f4cfa62019-06-27 14:56:51 -03001957 See Documentation/admin-guide/efi-stub.rst for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001958
Matt Fleming7d453ee2014-01-10 18:52:06 +00001959config EFI_MIXED
1960 bool "EFI mixed-mode support"
1961 depends on EFI_STUB && X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001962 help
Matt Fleming7d453ee2014-01-10 18:52:06 +00001963 Enabling this feature allows a 64-bit kernel to be booted
1964 on a 32-bit firmware, provided that your CPU supports 64-bit
1965 mode.
1966
1967 Note that it is not possible to boot a mixed-mode enabled
1968 kernel via the EFI boot stub - a bootloader that supports
1969 the EFI handover protocol must be used.
1970
1971 If unsure, say N.
1972
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001973config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001974 def_bool y
1975 prompt "Enable seccomp to safely compute untrusted bytecode"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001976 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001977 This kernel feature is useful for number crunching applications
1978 that may need to compute untrusted bytecode during their
1979 execution. By using pipes or other transports made available to
1980 the process as file descriptors supporting the read/write
1981 syscalls, it's possible to isolate those applications in
1982 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001983 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001984 and the task is only allowed to execute a few safe syscalls
1985 defined by each seccomp mode.
1986
1987 If unsure, say Y. Only embedded should say N here.
1988
Masahiro Yamada8636a1f2018-12-11 20:01:04 +09001989source "kernel/Kconfig.hz"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001990
1991config KEXEC
1992 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001993 select KEXEC_CORE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001994 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001995 kexec is a system call that implements the ability to shutdown your
1996 current kernel, and to start another kernel. It is like a reboot
1997 but it is independent of the system firmware. And like a reboot
1998 you can start any kernel with it, not just Linux.
1999
2000 The name comes from the similarity to the exec system call.
2001
2002 It is an ongoing process to be certain the hardware in a machine
2003 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02002004 initially work for you. As of this writing the exact hardware
2005 interface is strongly in flux, so no good recommendation can be
2006 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002007
Vivek Goyal74ca3172014-08-29 15:18:46 -07002008config KEXEC_FILE
2009 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07002010 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07002011 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07002012 depends on X86_64
2013 depends on CRYPTO=y
2014 depends on CRYPTO_SHA256=y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002015 help
Vivek Goyal74ca3172014-08-29 15:18:46 -07002016 This is new version of kexec system call. This system call is
2017 file based and takes file descriptors as system call argument
2018 for kernel and initramfs as opposed to list of segments as
2019 accepted by previous system call.
2020
AKASHI Takahirob799a092018-04-13 15:35:45 -07002021config ARCH_HAS_KEXEC_PURGATORY
2022 def_bool KEXEC_FILE
2023
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07002024config KEXEC_SIG
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002025 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07002026 depends on KEXEC_FILE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002027 help
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07002028
2029 This option makes the kexec_file_load() syscall check for a valid
2030 signature of the kernel image. The image can still be loaded without
2031 a valid signature unless you also enable KEXEC_SIG_FORCE, though if
2032 there's a signature that we can check, then it must be valid.
2033
2034 In addition to this option, you need to enable signature
2035 verification for the corresponding kernel image type being
2036 loaded in order for this to work.
2037
2038config KEXEC_SIG_FORCE
2039 bool "Require a valid signature in kexec_file_load() syscall"
2040 depends on KEXEC_SIG
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002041 help
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002042 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002043 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002044
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002045config KEXEC_BZIMAGE_VERIFY_SIG
2046 bool "Enable bzImage signature verification support"
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07002047 depends on KEXEC_SIG
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002048 depends on SIGNED_PE_FILE_VERIFICATION
2049 select SYSTEM_TRUSTED_KEYRING
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002050 help
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002051 Enable bzImage signature verification support.
2052
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002053config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002054 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002055 depends on X86_64 || (X86_32 && HIGHMEM)
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002056 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002057 Generate crash dump after being started by kexec.
2058 This should be normally only set in special crash dump kernels
2059 which are loaded in the main kernel with kexec-tools into
2060 a specially reserved region and then later executed after
2061 a crash by kdump/kexec. The crash dump kernel must be compiled
2062 to a memory address not used by the main kernel or BIOS using
2063 PHYSICAL_START, or it must be built as a relocatable image
2064 (CONFIG_RELOCATABLE=y).
Mauro Carvalho Chehab330d4812019-06-13 15:21:39 -03002065 For more details see Documentation/admin-guide/kdump/kdump.rst
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002066
Huang Ying3ab83522008-07-25 19:45:07 -07002067config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002068 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002069 depends on KEXEC && HIBERNATION
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002070 help
Huang Ying89081d12008-07-25 19:45:10 -07002071 Jump between original kernel and kexeced kernel and invoke
2072 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002073
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002074config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002075 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002076 default "0x1000000"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002077 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002078 This gives the physical address where the kernel is loaded.
2079
2080 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2081 bzImage will decompress itself to above physical address and
2082 run from there. Otherwise, bzImage will run from the address where
2083 it has been loaded by the boot loader and will ignore above physical
2084 address.
2085
2086 In normal kdump cases one does not have to set/change this option
2087 as now bzImage can be compiled as a completely relocatable image
2088 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2089 address. This option is mainly useful for the folks who don't want
2090 to use a bzImage for capturing the crash dump and want to use a
2091 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2092 to be specifically compiled to run from a specific memory area
2093 (normally a reserved region) and this option comes handy.
2094
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002095 So if you are using bzImage for capturing the crash dump,
2096 leave the value here unchanged to 0x1000000 and set
2097 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2098 for capturing the crash dump change this value to start of
2099 the reserved region. In other words, it can be set based on
2100 the "X" value as specified in the "crashkernel=YM@XM"
2101 command line boot parameter passed to the panic-ed
Mauro Carvalho Chehab330d4812019-06-13 15:21:39 -03002102 kernel. Please take a look at Documentation/admin-guide/kdump/kdump.rst
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002103 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002104
2105 Usage of bzImage for capturing the crash dump is recommended as
2106 one does not have to build two kernels. Same kernel can be used
2107 as production kernel and capture kernel. Above option should have
2108 gone away after relocatable bzImage support is introduced. But it
2109 is present because there are users out there who continue to use
2110 vmlinux for dump capture. This option should go away down the
2111 line.
2112
2113 Don't change this unless you know what you are doing.
2114
2115config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002116 bool "Build a relocatable kernel"
2117 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002118 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002119 This builds a kernel image that retains relocation information
2120 so it can be loaded someplace besides the default 1MB.
2121 The relocations tend to make the kernel binary about 10% larger,
2122 but are discarded at runtime.
2123
2124 One use is for the kexec on panic case where the recovery kernel
2125 must live at a different physical address than the primary
2126 kernel.
2127
2128 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2129 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002130 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002131
Kees Cook8ab38202013-10-10 17:18:14 -07002132config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002133 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002134 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002135 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002136 help
Baoquan Hee8581e32016-04-20 13:55:43 -07002137 In support of Kernel Address Space Layout Randomization (KASLR),
2138 this randomizes the physical address at which the kernel image
2139 is decompressed and the virtual address where the kernel
2140 image is mapped, as a security feature that deters exploit
2141 attempts relying on knowledge of the location of kernel
2142 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002143
Kees Cooked9f0072016-05-25 15:45:33 -07002144 On 64-bit, the kernel physical and virtual addresses are
2145 randomized separately. The physical address will be anywhere
2146 between 16MB and the top of physical memory (up to 64TB). The
2147 virtual address will be randomized from 16MB up to 1GB (9 bits
2148 of entropy). Note that this also reduces the memory space
2149 available to kernel modules from 1.5GB to 1GB.
2150
2151 On 32-bit, the kernel physical and virtual addresses are
2152 randomized together. They will be randomized from 16MB up to
2153 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002154
Baoquan Hee8581e32016-04-20 13:55:43 -07002155 Entropy is generated using the RDRAND instruction if it is
2156 supported. If RDTSC is supported, its value is mixed into
2157 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002158 supported, then entropy is read from the i8254 timer. The
2159 usable entropy is limited by the kernel being built using
2160 2GB addressing, and that PHYSICAL_ALIGN must be at a
2161 minimum of 2MB. As a result, only 10 bits of entropy are
2162 theoretically possible, but the implementations are further
2163 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002164
Ingo Molnar6807c842017-04-18 11:08:12 +02002165 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002166
2167# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002168config X86_NEED_RELOCS
2169 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002170 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002171
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002172config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002173 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002174 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002175 range 0x2000 0x1000000 if X86_32
2176 range 0x200000 0x1000000 if X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002177 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002178 This value puts the alignment restrictions on physical address
2179 where kernel is loaded and run from. Kernel is compiled for an
2180 address which meets above alignment restriction.
2181
2182 If bootloader loads the kernel at a non-aligned address and
2183 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2184 address aligned to above value and run from there.
2185
2186 If bootloader loads the kernel at a non-aligned address and
2187 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2188 load address and decompress itself to the address it has been
2189 compiled for and run from there. The address for which kernel is
2190 compiled already meets above alignment restrictions. Hence the
2191 end result is that kernel runs from a physical address meeting
2192 above alignment restrictions.
2193
Kees Cooka0215062013-07-08 09:15:17 -07002194 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2195 this value must be a multiple of 0x200000.
2196
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002197 Don't change this unless you know what you are doing.
2198
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002199config DYNAMIC_MEMORY_LAYOUT
2200 bool
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002201 help
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002202 This option makes base addresses of vmalloc and vmemmap as well as
2203 __PAGE_OFFSET movable during boot.
2204
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002205config RANDOMIZE_MEMORY
2206 bool "Randomize the kernel memory sections"
2207 depends on X86_64
2208 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002209 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002210 default RANDOMIZE_BASE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002211 help
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002212 Randomizes the base virtual address of kernel memory sections
2213 (physical memory mapping, vmalloc & vmemmap). This security feature
2214 makes exploits relying on predictable memory locations less reliable.
2215
2216 The order of allocations remains unchanged. Entropy is generated in
2217 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2218 configuration have in average 30,000 different possible virtual
2219 addresses for each memory section.
2220
Ingo Molnar6807c842017-04-18 11:08:12 +02002221 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002222
Thomas Garnier90397a42016-06-21 17:47:06 -07002223config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2224 hex "Physical memory mapping padding" if EXPERT
2225 depends on RANDOMIZE_MEMORY
2226 default "0xa" if MEMORY_HOTPLUG
2227 default "0x0"
2228 range 0x1 0x40 if MEMORY_HOTPLUG
2229 range 0x0 0x40
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002230 help
Thomas Garnier90397a42016-06-21 17:47:06 -07002231 Define the padding in terabytes added to the existing physical
2232 memory size during kernel memory randomization. It is useful
2233 for memory hotplug support but reduces the entropy available for
2234 address randomization.
2235
2236 If unsure, leave at the default value.
2237
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002238config HOTPLUG_CPU
Thomas Gleixnerbebd0242019-03-26 17:36:06 +01002239 def_bool y
Stephen Rothwell40b31362013-05-21 13:49:35 +10002240 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002241
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002242config BOOTPARAM_HOTPLUG_CPU0
2243 bool "Set default setting of cpu0_hotpluggable"
Kees Cook2c922cd2013-01-22 13:01:19 -08002244 depends on HOTPLUG_CPU
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002245 help
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002246 Set whether default state of cpu0_hotpluggable is on or off.
2247
2248 Say Y here to enable CPU0 hotplug by default. If this switch
2249 is turned on, there is no need to give cpu0_hotplug kernel
2250 parameter and the CPU0 hotplug feature is enabled by default.
2251
2252 Please note: there are two known CPU0 dependencies if you want
2253 to enable the CPU0 hotplug feature either by this switch or by
2254 cpu0_hotplug kernel parameter.
2255
2256 First, resume from hibernate or suspend always starts from CPU0.
2257 So hibernate and suspend are prevented if CPU0 is offline.
2258
2259 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2260 offline if any interrupt can not migrate out of CPU0. There may
2261 be other CPU0 dependencies.
2262
2263 Please make sure the dependencies are under your control before
2264 you enable this feature.
2265
2266 Say N if you don't want to enable CPU0 hotplug feature by default.
2267 You still can enable the CPU0 hotplug feature at boot by kernel
2268 parameter cpu0_hotplug.
2269
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002270config DEBUG_HOTPLUG_CPU0
2271 def_bool n
2272 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002273 depends on HOTPLUG_CPU
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002274 help
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002275 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2276 soon as possible and boots up userspace with CPU0 offlined. User
2277 can online CPU0 back after boot time.
2278
2279 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2280 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2281 compilation or giving cpu0_hotplug kernel parameter at boot.
2282
2283 If unsure, say N.
2284
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002285config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002286 def_bool n
2287 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002288 depends on COMPAT_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002289 help
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002290 Certain buggy versions of glibc will crash if they are
2291 presented with a 32-bit vDSO that is not mapped at the address
2292 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002293
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002294 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2295 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2296 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2297 the only released version with the bug, but OpenSUSE 9
2298 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002299
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002300 The symptom of the bug is that everything crashes on startup, saying:
2301 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2302
2303 Saying Y here changes the default value of the vdso32 boot
2304 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2305 This works around the glibc bug but hurts performance.
2306
2307 If unsure, say N: if you are compiling your own kernel, you
2308 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002309
Kees Cook3dc33bd2015-08-12 17:55:19 -07002310choice
2311 prompt "vsyscall table for legacy applications"
2312 depends on X86_64
Andy Lutomirski625b7b72019-06-26 21:45:07 -07002313 default LEGACY_VSYSCALL_XONLY
Kees Cook3dc33bd2015-08-12 17:55:19 -07002314 help
2315 Legacy user code that does not know how to find the vDSO expects
2316 to be able to issue three syscalls by calling fixed addresses in
2317 kernel space. Since this location is not randomized with ASLR,
2318 it can be used to assist security vulnerability exploitation.
2319
2320 This setting can be changed at boot time via the kernel command
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002321 line parameter vsyscall=[emulate|xonly|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002322
2323 On a system with recent enough glibc (2.14 or newer) and no
2324 static binaries, you can say None without a performance penalty
2325 to improve security.
2326
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002327 If unsure, select "Emulate execution only".
Kees Cook3dc33bd2015-08-12 17:55:19 -07002328
Kees Cook3dc33bd2015-08-12 17:55:19 -07002329 config LEGACY_VSYSCALL_EMULATE
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002330 bool "Full emulation"
Kees Cook3dc33bd2015-08-12 17:55:19 -07002331 help
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002332 The kernel traps and emulates calls into the fixed vsyscall
2333 address mapping. This makes the mapping non-executable, but
2334 it still contains readable known contents, which could be
2335 used in certain rare security vulnerability exploits. This
2336 configuration is recommended when using legacy userspace
2337 that still uses vsyscalls along with legacy binary
2338 instrumentation tools that require code to be readable.
2339
2340 An example of this type of legacy userspace is running
2341 Pin on an old binary that still uses vsyscalls.
2342
2343 config LEGACY_VSYSCALL_XONLY
2344 bool "Emulate execution only"
2345 help
2346 The kernel traps and emulates calls into the fixed vsyscall
2347 address mapping and does not allow reads. This
2348 configuration is recommended when userspace might use the
2349 legacy vsyscall area but support for legacy binary
2350 instrumentation of legacy code is not needed. It mitigates
2351 certain uses of the vsyscall area as an ASLR-bypassing
2352 buffer.
Kees Cook3dc33bd2015-08-12 17:55:19 -07002353
2354 config LEGACY_VSYSCALL_NONE
2355 bool "None"
2356 help
2357 There will be no vsyscall mapping at all. This will
2358 eliminate any risk of ASLR bypass due to the vsyscall
2359 fixed address mapping. Attempts to use the vsyscalls
2360 will be reported to dmesg, so that either old or
2361 malicious userspace programs can be identified.
2362
2363endchoice
2364
Tim Bird516cbf32008-08-12 12:52:36 -07002365config CMDLINE_BOOL
2366 bool "Built-in kernel command line"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002367 help
Tim Bird516cbf32008-08-12 12:52:36 -07002368 Allow for specifying boot arguments to the kernel at
2369 build time. On some systems (e.g. embedded ones), it is
2370 necessary or convenient to provide some or all of the
2371 kernel boot arguments with the kernel itself (that is,
2372 to not rely on the boot loader to provide them.)
2373
2374 To compile command line arguments into the kernel,
2375 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002376 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002377
2378 Systems with fully functional boot loaders (i.e. non-embedded)
2379 should leave this option set to 'N'.
2380
2381config CMDLINE
2382 string "Built-in kernel command string"
2383 depends on CMDLINE_BOOL
2384 default ""
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002385 help
Tim Bird516cbf32008-08-12 12:52:36 -07002386 Enter arguments here that should be compiled into the kernel
2387 image and used at boot time. If the boot loader provides a
2388 command line at boot time, it is appended to this string to
2389 form the full kernel command line, when the system boots.
2390
2391 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2392 change this behavior.
2393
2394 In most cases, the command line (whether built-in or provided
2395 by the boot loader) should specify the device for the root
2396 file system.
2397
2398config CMDLINE_OVERRIDE
2399 bool "Built-in command line overrides boot loader arguments"
Anders Roxell645e6462020-01-24 12:46:15 +01002400 depends on CMDLINE_BOOL && CMDLINE != ""
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002401 help
Tim Bird516cbf32008-08-12 12:52:36 -07002402 Set this option to 'Y' to have the kernel ignore the boot loader
2403 command line, and use ONLY the built-in command line.
2404
2405 This is used to work around broken boot loaders. This should
2406 be set to 'N' under normal conditions.
2407
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002408config MODIFY_LDT_SYSCALL
2409 bool "Enable the LDT (local descriptor table)" if EXPERT
2410 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002411 help
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002412 Linux can allow user programs to install a per-process x86
2413 Local Descriptor Table (LDT) using the modify_ldt(2) system
2414 call. This is required to run 16-bit or segmented code such as
2415 DOSEMU or some Wine programs. It is also used by some very old
2416 threading libraries.
2417
2418 Enabling this feature adds a small amount of overhead to
2419 context switches and increases the low-level kernel attack
2420 surface. Disabling it removes the modify_ldt(2) system call.
2421
2422 Saying 'N' here may make sense for embedded or server kernels.
2423
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002424source "kernel/livepatch/Kconfig"
2425
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002426endmenu
2427
Michal Hocko3072e412017-09-08 16:11:39 -07002428config ARCH_HAS_ADD_PAGES
2429 def_bool y
2430 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2431
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002432config ARCH_ENABLE_MEMORY_HOTPLUG
2433 def_bool y
2434 depends on X86_64 || (X86_32 && HIGHMEM)
2435
Gary Hade35551052008-10-31 10:52:03 -07002436config ARCH_ENABLE_MEMORY_HOTREMOVE
2437 def_bool y
2438 depends on MEMORY_HOTPLUG
2439
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002440config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002441 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002442 depends on NUMA
2443
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002444config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2445 def_bool y
2446 depends on X86_64 || X86_PAE
2447
Naoya Horiguchic177c812014-06-04 16:05:35 -07002448config ARCH_ENABLE_HUGEPAGE_MIGRATION
2449 def_bool y
2450 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2451
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002452config ARCH_ENABLE_THP_MIGRATION
2453 def_bool y
2454 depends on X86_64 && TRANSPARENT_HUGEPAGE
2455
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002456menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002457
2458config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002459 def_bool y
Zhimin Gu44556532018-09-21 14:27:29 +08002460 depends on HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002461
2462source "kernel/power/Kconfig"
2463
2464source "drivers/acpi/Kconfig"
2465
Feng Tangefafc8b2009-08-14 15:23:29 -04002466source "drivers/sfi/Kconfig"
2467
Andi Kleena6b68072008-01-30 13:32:49 +01002468config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002469 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002470 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002471
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002472menuconfig APM
2473 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002474 depends on X86_32 && PM_SLEEP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002475 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002476 APM is a BIOS specification for saving power using several different
2477 techniques. This is mostly useful for battery powered laptops with
2478 APM compliant BIOSes. If you say Y here, the system time will be
2479 reset after a RESUME operation, the /proc/apm device will provide
2480 battery status information, and user-space programs will receive
2481 notification of APM "events" (e.g. battery status change).
2482
2483 If you select "Y" here, you can disable actual use of the APM
2484 BIOS by passing the "apm=off" option to the kernel at boot time.
2485
2486 Note that the APM support is almost completely disabled for
2487 machines with more than one CPU.
2488
2489 In order to use APM, you will need supporting software. For location
Mauro Carvalho Chehab151f4e22019-06-13 07:10:36 -03002490 and more information, read <file:Documentation/power/apm-acpi.rst>
Michael Witten2dc98fd2011-07-08 21:11:16 +00002491 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002492 <http://www.tldp.org/docs.html#howto>.
2493
2494 This driver does not spin down disk drives (see the hdparm(8)
2495 manpage ("man 8 hdparm") for that), and it doesn't turn off
2496 VESA-compliant "green" monitors.
2497
2498 This driver does not support the TI 4000M TravelMate and the ACER
2499 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2500 desktop machines also don't have compliant BIOSes, and this driver
2501 may cause those machines to panic during the boot phase.
2502
2503 Generally, if you don't have a battery in your machine, there isn't
2504 much point in using this driver and you should say N. If you get
2505 random kernel OOPSes or reboots that don't seem to be related to
2506 anything, try disabling/enabling this option (or disabling/enabling
2507 APM in your BIOS).
2508
2509 Some other things you should try when experiencing seemingly random,
2510 "weird" problems:
2511
2512 1) make sure that you have enough swap space and that it is
2513 enabled.
2514 2) pass the "no-hlt" option to the kernel
2515 3) switch on floating point emulation in the kernel and pass
2516 the "no387" option to the kernel
2517 4) pass the "floppy=nodma" option to the kernel
2518 5) pass the "mem=4M" option to the kernel (thereby disabling
2519 all but the first 4 MB of RAM)
2520 6) make sure that the CPU is not over clocked.
2521 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2522 8) disable the cache from your BIOS settings
2523 9) install a fan for the video card or exchange video RAM
2524 10) install a better fan for the CPU
2525 11) exchange RAM chips
2526 12) exchange the motherboard.
2527
2528 To compile this driver as a module, choose M here: the
2529 module will be called apm.
2530
2531if APM
2532
2533config APM_IGNORE_USER_SUSPEND
2534 bool "Ignore USER SUSPEND"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002535 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002536 This option will ignore USER SUSPEND requests. On machines with a
2537 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2538 series notebooks, it is necessary to say Y because of a BIOS bug.
2539
2540config APM_DO_ENABLE
2541 bool "Enable PM at boot time"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002542 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002543 Enable APM features at boot time. From page 36 of the APM BIOS
2544 specification: "When disabled, the APM BIOS does not automatically
2545 power manage devices, enter the Standby State, enter the Suspend
2546 State, or take power saving steps in response to CPU Idle calls."
2547 This driver will make CPU Idle calls when Linux is idle (unless this
2548 feature is turned off -- see "Do CPU IDLE calls", below). This
2549 should always save battery power, but more complicated APM features
2550 will be dependent on your BIOS implementation. You may need to turn
2551 this option off if your computer hangs at boot time when using APM
2552 support, or if it beeps continuously instead of suspending. Turn
2553 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2554 T400CDT. This is off by default since most machines do fine without
2555 this feature.
2556
2557config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002558 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002559 bool "Make CPU Idle calls when idle"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002560 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002561 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2562 On some machines, this can activate improved power savings, such as
2563 a slowed CPU clock rate, when the machine is idle. These idle calls
2564 are made after the idle loop has run for some length of time (e.g.,
2565 333 mS). On some machines, this will cause a hang at boot time or
2566 whenever the CPU becomes idle. (On machines with more than one CPU,
2567 this option does nothing.)
2568
2569config APM_DISPLAY_BLANK
2570 bool "Enable console blanking using APM"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002571 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002572 Enable console blanking using the APM. Some laptops can use this to
2573 turn off the LCD backlight when the screen blanker of the Linux
2574 virtual console blanks the screen. Note that this is only used by
2575 the virtual console screen blanker, and won't turn off the backlight
2576 when using the X Window system. This also doesn't have anything to
2577 do with your VESA-compliant power-saving monitor. Further, this
2578 option doesn't work for all laptops -- it might not turn off your
2579 backlight at all, or it might print a lot of errors to the console,
2580 especially if you are using gpm.
2581
2582config APM_ALLOW_INTS
2583 bool "Allow interrupts during APM BIOS calls"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002584 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002585 Normally we disable external interrupts while we are making calls to
2586 the APM BIOS as a measure to lessen the effects of a badly behaving
2587 BIOS implementation. The BIOS should reenable interrupts if it
2588 needs to. Unfortunately, some BIOSes do not -- especially those in
2589 many of the newer IBM Thinkpads. If you experience hangs when you
2590 suspend, try setting this to Y. Otherwise, say N.
2591
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002592endif # APM
2593
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002594source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002595
2596source "drivers/cpuidle/Kconfig"
2597
Andy Henroid27471fd2008-10-09 11:45:22 -07002598source "drivers/idle/Kconfig"
2599
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002600endmenu
2601
2602
2603menu "Bus options (PCI etc.)"
2604
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002605choice
2606 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002607 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002608 default PCI_GOANY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002609 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002610 On PCI systems, the BIOS can be used to detect the PCI devices and
2611 determine their configuration. However, some old PCI motherboards
2612 have BIOS bugs and may crash if this is done. Also, some embedded
2613 PCI-based systems don't have any BIOS at all. Linux can also try to
2614 detect the PCI hardware directly without using the BIOS.
2615
2616 With this option, you can specify how Linux should detect the
2617 PCI devices. If you choose "BIOS", the BIOS will be used,
2618 if you choose "Direct", the BIOS won't be used, and if you
2619 choose "MMConfig", then PCI Express MMCONFIG will be used.
2620 If you choose "Any", the kernel will try MMCONFIG, then the
2621 direct access method and falls back to the BIOS if that doesn't
2622 work. If unsure, go with the default, which is "Any".
2623
2624config PCI_GOBIOS
2625 bool "BIOS"
2626
2627config PCI_GOMMCONFIG
2628 bool "MMConfig"
2629
2630config PCI_GODIRECT
2631 bool "Direct"
2632
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002633config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002634 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002635 depends on OLPC
2636
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002637config PCI_GOANY
2638 bool "Any"
2639
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002640endchoice
2641
2642config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002643 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002644 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002645
2646# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2647config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002648 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002649 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002650
2651config PCI_MMCONFIG
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002652 bool "Support mmconfig PCI config space access" if X86_64
2653 default y
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002654 depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002655 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002656
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002657config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002658 def_bool y
2659 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002660
Alex Nixonb5401a92010-03-18 16:31:34 -04002661config PCI_XEN
2662 def_bool y
2663 depends on PCI && XEN
2664 select SWIOTLB_XEN
2665
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002666config MMCONF_FAM10H
2667 def_bool y
2668 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002669
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002670config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002671 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002672 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002673 help
2674 Read the PCI windows out of the CNB20LE host bridge. This allows
2675 PCI hotplug to work on systems with the CNB20LE chipset which do
2676 not have ACPI.
2677
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002678 There's no public spec for this chipset, and this functionality
2679 is known to be incomplete.
2680
2681 You should say N unless you know you need this.
2682
William Breathitt Gray3a495512016-05-27 18:08:27 -04002683config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002684 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002685 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002686 Expose ISA bus device drivers and options available for selection and
2687 configuration. Enable this option if your target machine has an ISA
2688 bus. ISA is an older system, displaced by PCI and newer bus
2689 architectures -- if your target machine is modern, it probably does
2690 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002691
2692 If unsure, say N.
2693
David Rientjes1c00f012011-03-22 16:34:59 -07002694# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002695config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002696 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2697 default y
2698 help
2699 Enables ISA-style DMA support for devices requiring such controllers.
2700 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002701
Linus Torvalds51e68d02016-05-21 10:25:19 -07002702if X86_32
2703
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002704config ISA
2705 bool "ISA support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002706 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002707 Find out whether you have ISA slots on your motherboard. ISA is the
2708 name of a bus system, i.e. the way the CPU talks to the other stuff
2709 inside your box. Other bus systems are PCI, EISA, MicroChannel
2710 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2711 newer boards don't support it. If you have ISA, say Y, otherwise N.
2712
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002713config SCx200
2714 tristate "NatSemi SCx200 support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002715 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002716 This provides basic support for National Semiconductor's
2717 (now AMD's) Geode processors. The driver probes for the
2718 PCI-IDs of several on-chip devices, so its a good dependency
2719 for other scx200_* drivers.
2720
2721 If compiled as a module, the driver is named scx200.
2722
2723config SCx200HR_TIMER
2724 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002725 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002726 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002727 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002728 This driver provides a clocksource built upon the on-chip
2729 27MHz high-resolution timer. Its also a workaround for
2730 NSC Geode SC-1100's buggy TSC, which loses time when the
2731 processor goes idle (as is done by the scheduler). The
2732 other workaround is idle=poll boot option.
2733
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002734config OLPC
2735 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002736 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002737 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002738 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002739 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002740 select IRQ_DOMAIN
Lubomir Rintel0c3d9312019-05-13 09:56:37 +02002741 select OLPC_EC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002742 help
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002743 Add support for detecting the unique features of the OLPC
2744 XO hardware.
2745
Daniel Drakea3128582011-06-25 17:34:10 +01002746config OLPC_XO1_PM
2747 bool "OLPC XO-1 Power Management"
Borislav Petkovfa112cf2018-10-05 15:13:07 +02002748 depends on OLPC && MFD_CS5535=y && PM_SLEEP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002749 help
Daniel Drake97c4cb72011-06-25 17:34:11 +01002750 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002751
Daniel Drakecfee9592011-06-25 17:34:17 +01002752config OLPC_XO1_RTC
2753 bool "OLPC XO-1 Real Time Clock"
2754 depends on OLPC_XO1_PM && RTC_DRV_CMOS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002755 help
Daniel Drakecfee9592011-06-25 17:34:17 +01002756 Add support for the XO-1 real time clock, which can be used as a
2757 programmable wakeup source.
2758
Daniel Drake7feda8e2011-06-25 17:34:12 +01002759config OLPC_XO1_SCI
2760 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002761 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002762 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002763 select POWER_SUPPLY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002764 help
Daniel Drake7feda8e2011-06-25 17:34:12 +01002765 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002766 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002767 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002768 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002769 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002770 - AC adapter status updates
2771 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002772
Daniel Drakea0f30f52011-06-25 17:34:18 +01002773config OLPC_XO15_SCI
2774 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002775 depends on OLPC && ACPI
2776 select POWER_SUPPLY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002777 help
Daniel Drakea0f30f52011-06-25 17:34:18 +01002778 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2779 - EC-driven system wakeups
2780 - AC adapter status updates
2781 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002782
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002783config ALIX
2784 bool "PCEngines ALIX System Support (LED setup)"
2785 select GPIOLIB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002786 help
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002787 This option enables system support for the PCEngines ALIX.
2788 At present this just sets up LEDs for GPIO control on
2789 ALIX2/3/6 boards. However, other system specific setup should
2790 get added here.
2791
2792 Note: You must still enable the drivers for GPIO and LED support
2793 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2794
2795 Note: You have to set alix.force=1 for boards with Award BIOS.
2796
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002797config NET5501
2798 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2799 select GPIOLIB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002800 help
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002801 This option enables system support for the Soekris Engineering net5501.
2802
Philip A. Prindeville31970592012-01-14 01:45:39 -07002803config GEOS
2804 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2805 select GPIOLIB
2806 depends on DMI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002807 help
Philip A. Prindeville31970592012-01-14 01:45:39 -07002808 This option enables system support for the Traverse Technologies GEOS.
2809
Vivien Didelot7d029122013-01-04 16:18:14 -05002810config TS5500
2811 bool "Technologic Systems TS-5500 platform support"
2812 depends on MELAN
2813 select CHECK_SIGNATURE
2814 select NEW_LEDS
2815 select LEDS_CLASS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002816 help
Vivien Didelot7d029122013-01-04 16:18:14 -05002817 This option enables system support for the Technologic Systems TS-5500.
2818
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002819endif # X86_32
2820
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002821config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002822 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002823 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002824
David Herrmanne3263ab2013-08-02 14:05:22 +02002825config X86_SYSFB
2826 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2827 help
2828 Firmwares often provide initial graphics framebuffers so the BIOS,
2829 bootloader or kernel can show basic video-output during boot for
2830 user-guidance and debugging. Historically, x86 used the VESA BIOS
2831 Extensions and EFI-framebuffers for this, which are mostly limited
2832 to x86.
2833 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2834 framebuffers so the new generic system-framebuffer drivers can be
2835 used on x86. If the framebuffer is not compatible with the generic
Nikolas Nybye3a5dc02018-08-25 19:10:54 -04002836 modes, it is advertised as fallback platform framebuffer so legacy
David Herrmanne3263ab2013-08-02 14:05:22 +02002837 drivers like efifb, vesafb and uvesafb can pick it up.
2838 If this option is not selected, all system framebuffers are always
2839 marked as fallback platform framebuffers as usual.
2840
2841 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2842 not be able to pick up generic system framebuffers if this option
2843 is selected. You are highly encouraged to enable simplefb as
2844 replacement if you select this option. simplefb can correctly deal
2845 with generic system framebuffers. But you should still keep vesafb
2846 and others enabled as fallback if a system framebuffer is
2847 incompatible with simplefb.
2848
2849 If unsure, say Y.
2850
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002851endmenu
2852
2853
Christoph Hellwig15724972018-07-31 13:39:30 +02002854menu "Binary Emulations"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002855
2856config IA32_EMULATION
2857 bool "IA32 Emulation"
2858 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002859 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002860 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002861 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002862 select COMPAT_OLD_SIGACTION
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002863 help
H. J. Lu5fd92e62012-02-19 10:40:03 -08002864 Include code to run legacy 32-bit programs under a
2865 64-bit kernel. You should likely turn this on, unless you're
2866 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002867
2868config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002869 tristate "IA32 a.out support"
2870 depends on IA32_EMULATION
Borislav Petkoveac61652019-03-05 15:47:51 +01002871 depends on BROKEN
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002872 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002873 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002874
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002875config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002876 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002877 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002878 help
H. J. Lu5fd92e62012-02-19 10:40:03 -08002879 Include code to run binaries for the x32 native 32-bit ABI
2880 for 64-bit processors. An x32 process gets access to the
2881 full 64-bit register file and wide data path while leaving
2882 pointers at 32 bits for smaller memory footprint.
2883
2884 You will need a recent binutils (2.22 or later) with
2885 elf32_x86_64 support enabled to compile a kernel with this
2886 option set.
2887
Ingo Molnar953fee12016-11-15 10:22:52 +01002888config COMPAT_32
2889 def_bool y
2890 depends on IA32_EMULATION || X86_32
2891 select HAVE_UID16
2892 select OLD_SIGSUSPEND3
2893
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002894config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002895 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002896 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002897
Jan Beulich3120e252012-09-10 12:41:45 +01002898if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002899config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002900 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002901
2902config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002903 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002904 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002905endif
David Howellsee009e4a02011-03-07 15:06:20 +00002906
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002907endmenu
2908
2909
Keith Packarde5beae12008-11-03 18:21:45 +01002910config HAVE_ATOMIC_IOMAP
2911 def_bool y
2912 depends on X86_32
2913
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002914source "drivers/firmware/Kconfig"
2915
Avi Kivityedf88412007-12-16 11:02:48 +02002916source "arch/x86/kvm/Kconfig"
Jason A. Donenfeld5e8ebd82020-03-26 17:00:58 +09002917
2918source "arch/x86/Kconfig.assembler"