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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"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01006 ---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
17 select HAVE_AOUT
18 select HAVE_GENERIC_DMA_COHERENT
19 select MODULES_USE_ELF_REL
20 select OLD_SIGACTION
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:
Aneesh Kumar K.Ve1073d12017-07-06 15:39:17 -070026 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
Ingo Molnard94e0682016-11-15 10:11:57 +010027 select ARCH_SUPPORTS_INT128
28 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
Ingo Molnard94e0682016-11-15 10:11:57 +010033 select X86_DEV_DMA_OPS
Dominik Brodowskif8781c42018-04-05 11:53:05 +020034 select ARCH_HAS_SYSCALL_WRAPPER
Sam Ravnborg1032c0b2007-11-06 21:35:08 +010035
Ingo Molnard94e0682016-11-15 10:11:57 +010036#
37# Arch settings
38#
39# ( Note that options that are marked 'if X86_64' could in principle be
40# ported to 32-bit as well. )
41#
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +010042config X86
Harvey Harrison3c2362e2008-01-30 13:31:03 +010043 def_bool y
Ingo Molnarc763ea22016-11-15 10:26:39 +010044 #
45 # Note: keep this list sorted alphabetically
46 #
Ingo Molnar6471b822015-06-03 10:00:13 +020047 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
48 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
49 select ANON_INODES
50 select ARCH_CLOCKSOURCE_DATA
51 select ARCH_DISCARD_MEMBLOCK
Ingo Molnarc763ea22016-11-15 10:26:39 +010052 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
Laura Abbottfa5b6ec2017-01-10 13:35:40 -080053 select ARCH_HAS_DEBUG_VIRTUAL
Dan Williams21266be2015-11-19 18:19:29 -080054 select ARCH_HAS_DEVMEM_IS_ALLOWED
Ingo Molnar6471b822015-06-03 10:00:13 +020055 select ARCH_HAS_ELF_RANDOMIZE
Linus Torvalds72d93102014-09-13 11:14:53 -070056 select ARCH_HAS_FAST_MULTIPLIER
Dave Hansen316d0972018-04-20 15:20:28 -070057 select ARCH_HAS_FILTER_PGPROT
Daniel Micay6974f0c2017-07-12 14:36:10 -070058 select ARCH_HAS_FORTIFY_SOURCE
Riku Voipio957e3fa2014-12-12 16:57:44 -080059 select ARCH_HAS_GCOV_PROFILE_ALL
Dmitry Vyukov5c9a8752016-03-22 14:27:30 -070060 select ARCH_HAS_KCOV if X86_64
Mathieu Desnoyers10bcc802018-01-29 15:20:18 -050061 select ARCH_HAS_MEMBARRIER_SYNC_CORE
Ingo Molnarc763ea22016-11-15 10:26:39 +010062 select ARCH_HAS_PMEM_API if X86_64
Laurent Dufour3010a5e2018-06-07 17:06:08 -070063 select ARCH_HAS_PTE_SPECIAL
Kees Cook39208aa2017-09-02 13:09:46 -070064 select ARCH_HAS_REFCOUNT
Dan Williams0aed55a2017-05-29 12:22:50 -070065 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Dan Williams87803562018-05-03 17:06:31 -070066 select ARCH_HAS_UACCESS_MCSAFE if X86_64
Daniel Borkmannd2852a22017-02-21 16:09:33 +010067 select ARCH_HAS_SET_MEMORY
Ingo Molnar6471b822015-06-03 10:00:13 +020068 select ARCH_HAS_SG_CHAIN
Laura Abbottad21fc42017-02-06 16:31:57 -080069 select ARCH_HAS_STRICT_KERNEL_RWX
70 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050071 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Andrey Ryabininc6d30852016-01-20 15:00:55 -080072 select ARCH_HAS_UBSAN_SANITIZE_ALL
Oliver O'Halloran65f7d042017-06-28 11:32:31 +100073 select ARCH_HAS_ZONE_DEVICE if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020074 select ARCH_HAVE_NMI_SAFE_CMPXCHG
75 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040076 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080077 select ARCH_MIGHT_HAVE_PC_SERIO
Ingo Molnar6471b822015-06-03 10:00:13 +020078 select ARCH_SUPPORTS_ATOMIC_RMW
Ingo Molnar6471b822015-06-03 10:00:13 +020079 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
80 select ARCH_USE_BUILTIN_BSWAP
Ingo Molnar6471b822015-06-03 10:00:13 +020081 select ARCH_USE_QUEUED_RWLOCKS
82 select ARCH_USE_QUEUED_SPINLOCKS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -070083 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Ingo Molnarc763ea22016-11-15 10:26:39 +010084 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Huang Ying38d8b4e2017-07-06 15:37:18 -070085 select ARCH_WANTS_THP_SWAP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020086 select BUILDTIME_EXTABLE_SORT
87 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +020088 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
89 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +020090 select DCACHE_WORD_ACCESS
Christoph Hellwigfec777c2018-03-19 11:38:15 +010091 select DMA_DIRECT_OPS
Linus Torvalds45471cd2015-06-24 19:52:06 -070092 select EDAC_ATOMIC_SCRUB
93 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +020094 select GENERIC_CLOCKEVENTS
95 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
96 select GENERIC_CLOCKEVENTS_MIN_ADJUST
97 select GENERIC_CMOS_UPDATE
98 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +010099 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +0200100 select GENERIC_EARLY_IOREMAP
101 select GENERIC_FIND_FIRST_BIT
102 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +0200103 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +0200104 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +0200105 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200106 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200107 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200108 select GENERIC_IRQ_SHOW
109 select GENERIC_PENDING_IRQ if SMP
110 select GENERIC_SMP_IDLE_THREAD
111 select GENERIC_STRNCPY_FROM_USER
112 select GENERIC_STRNLEN_USER
113 select GENERIC_TIME_VSYSCALL
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200114 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200115 select HAVE_ACPI_APEI if ACPI
116 select HAVE_ACPI_APEI_NMI if ACPI
117 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200118 select HAVE_ARCH_AUDITSYSCALL
119 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
120 select HAVE_ARCH_JUMP_LABEL
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800121 select HAVE_ARCH_KASAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200122 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800123 select HAVE_ARCH_MMAP_RND_BITS if MMU
124 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300125 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ingo Molnar6471b822015-06-03 10:00:13 +0200126 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700127 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Ingo Molnar6471b822015-06-03 10:00:13 +0200128 select HAVE_ARCH_TRACEHOOK
129 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Matthew Wilcoxa00cc7d2017-02-24 14:57:02 -0800130 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
Andy Lutomirskie37e43a2016-08-11 02:35:23 -0700131 select HAVE_ARCH_VMAP_STACK if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100132 select HAVE_ARCH_WITHIN_STACK_FRAMES
Ingo Molnar6471b822015-06-03 10:00:13 +0200133 select HAVE_CMPXCHG_DOUBLE
134 select HAVE_CMPXCHG_LOCAL
135 select HAVE_CONTEXT_TRACKING if X86_64
Josh Triplettc1bd55f2015-06-30 15:00:00 -0700136 select HAVE_COPY_THREAD_TLS
Ingo Molnar6471b822015-06-03 10:00:13 +0200137 select HAVE_C_RECORDMCOUNT
138 select HAVE_DEBUG_KMEMLEAK
139 select HAVE_DEBUG_STACKOVERFLOW
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700140 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400141 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900142 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Wang YanQing03f57812018-05-03 14:10:43 +0800143 select HAVE_EBPF_JIT
Johannes Berg58340a02008-07-25 01:45:33 -0700144 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Jiri Slaby5f56a5d2016-05-20 17:00:16 -0700145 select HAVE_EXIT_THREAD
Steven Rostedt (VMware)644e0e82017-03-23 10:33:52 -0400146 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
Ingo Molnar6471b822015-06-03 10:00:13 +0200147 select HAVE_FTRACE_MCOUNT_RECORD
Ingo Molnar6471b822015-06-03 10:00:13 +0200148 select HAVE_FUNCTION_GRAPH_TRACER
149 select HAVE_FUNCTION_TRACER
Emese Revfy6b90bd42016-05-24 00:09:38 +0200150 select HAVE_GCC_PLUGINS
K.Prasad0067f122009-06-01 23:43:57 +0530151 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200152 select HAVE_IDE
153 select HAVE_IOREMAP_PROT
154 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
155 select HAVE_IRQ_TIME_ACCOUNTING
156 select HAVE_KERNEL_BZIP2
157 select HAVE_KERNEL_GZIP
158 select HAVE_KERNEL_LZ4
159 select HAVE_KERNEL_LZMA
160 select HAVE_KERNEL_LZO
161 select HAVE_KERNEL_XZ
162 select HAVE_KPROBES
163 select HAVE_KPROBES_ON_FTRACE
Masami Hiramatsu540adea2018-01-13 02:55:03 +0900164 select HAVE_FUNCTION_ERROR_INJECTION
Ingo Molnar6471b822015-06-03 10:00:13 +0200165 select HAVE_KRETPROBES
166 select HAVE_KVM
167 select HAVE_LIVEPATCH if X86_64
168 select HAVE_MEMBLOCK
169 select HAVE_MEMBLOCK_NODE_MAP
Frederic Weisbecker01027522010-04-11 18:55:56 +0200170 select HAVE_MIXED_BREAKPOINTS_REGS
Josh Poimboeufee9f8fc2017-07-24 18:36:57 -0500171 select HAVE_MOD_ARCH_SPECIFIC
Petr Mladek42a0bb32016-05-20 17:00:33 -0700172 select HAVE_NMI
Ingo Molnar6471b822015-06-03 10:00:13 +0200173 select HAVE_OPROFILE
174 select HAVE_OPTPROBES
175 select HAVE_PCSPKR_PLATFORM
176 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200177 select HAVE_PERF_EVENTS_NMI
Nicholas Piggin92e5aae2017-08-18 15:15:51 -0700178 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
Jiri Olsac5e63192012-08-07 15:20:36 +0200179 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200180 select HAVE_PERF_USER_STACK_DUMP
Vitaly Kuznetsov9e52fc22017-08-28 10:22:51 +0200181 select HAVE_RCU_TABLE_FREE
Ingo Molnar6471b822015-06-03 10:00:13 +0200182 select HAVE_REGS_AND_STACK_ACCESS_API
Josh Poimboeuf11af8472017-10-13 15:02:00 -0500183 select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
Masahiro Yamadad148eac2018-06-14 19:36:45 +0900184 select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
Ingo Molnarc763ea22016-11-15 10:26:39 +0100185 select HAVE_STACK_VALIDATION if X86_64
Mathieu Desnoyersd6761b82018-06-02 08:43:58 -0400186 select HAVE_RSEQ
Ingo Molnar6471b822015-06-03 10:00:13 +0200187 select HAVE_SYSCALL_TRACEPOINTS
Ingo Molnar6471b822015-06-03 10:00:13 +0200188 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300189 select HAVE_USER_RETURN_NOTIFIER
Thomas Gleixner05736e42018-05-29 17:48:27 +0200190 select HOTPLUG_SMT if SMP
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100191 select IRQ_FORCED_THREADING
Christoph Hellwig86596f02018-04-05 09:44:52 +0200192 select NEED_SG_DMA_LENGTH
Thomas Gleixnerdf65c1b2017-03-16 22:50:07 +0100193 select PCI_LOCKLESS_CONFIG
Ingo Molnar6471b822015-06-03 10:00:13 +0200194 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500195 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200196 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200197 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500198 select SRCU
Ingo Molnar6471b822015-06-03 10:00:13 +0200199 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700200 select THREAD_INFO_IN_TASK
Ingo Molnar6471b822015-06-03 10:00:13 +0200201 select USER_STACKTRACE_SUPPORT
202 select VIRT_TO_BUS
Ingo Molnar6471b822015-06-03 10:00:13 +0200203 select X86_FEATURE_NAMES if PROC_FS
Balbir Singh7d8330a2008-02-10 12:46:28 +0530204
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200205config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100206 def_bool y
207 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200208
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700209config OUTPUT_FORMAT
210 string
211 default "elf32-i386" if X86_32
212 default "elf64-x86-64" if X86_64
213
Sam Ravnborg73531902008-05-25 23:03:18 +0200214config ARCH_DEFCONFIG
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200215 string
Sam Ravnborg73531902008-05-25 23:03:18 +0200216 default "arch/x86/configs/i386_defconfig" if X86_32
217 default "arch/x86/configs/x86_64_defconfig" if X86_64
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200218
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100219config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100220 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100221
222config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100223 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100224
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100225config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100226 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100227
Daniel Cashman9e08f572016-01-14 15:20:06 -0800228config ARCH_MMAP_RND_BITS_MIN
229 default 28 if 64BIT
230 default 8
231
232config ARCH_MMAP_RND_BITS_MAX
233 default 32 if 64BIT
234 default 16
235
236config ARCH_MMAP_RND_COMPAT_BITS_MIN
237 default 8
238
239config ARCH_MMAP_RND_COMPAT_BITS_MAX
240 default 16
241
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100242config SBUS
243 bool
244
245config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100246 def_bool y
247 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100248
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100249config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100250 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100251 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000252 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
253
254config GENERIC_BUG_RELATIVE_POINTERS
255 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100256
257config GENERIC_HWEIGHT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100258 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100259
260config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100261 def_bool y
262 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100263
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100264config RWSEM_XCHGADD_ALGORITHM
Jan Beulich3120e252012-09-10 12:41:45 +0100265 def_bool y
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100266
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100267config GENERIC_CALIBRATE_DELAY
268 def_bool y
269
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800270config ARCH_HAS_CPU_RELAX
271 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100272
Pekka Enberg1b27d052008-04-28 02:12:22 -0700273config ARCH_HAS_CACHE_LINE_SIZE
274 def_bool y
275
Dave Hansen316d0972018-04-20 15:20:28 -0700276config ARCH_HAS_FILTER_PGPROT
277 def_bool y
278
Mike Travisdd5af902008-01-30 13:33:32 +0100279config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900280 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100281
Tejun Heo08fc4582009-08-14 15:00:49 +0900282config NEED_PER_CPU_EMBED_FIRST_CHUNK
283 def_bool y
284
285config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900286 def_bool y
287
Johannes Berg801e4062007-12-08 02:12:39 +0100288config ARCH_HIBERNATION_POSSIBLE
289 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100290
Johannes Bergf4cb5702007-12-08 02:14:00 +0100291config ARCH_SUSPEND_POSSIBLE
292 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100293
Steve Cappercfe28c52013-04-29 14:29:48 +0100294config ARCH_WANT_HUGE_PMD_SHARE
295 def_bool y
296
Steve Capper53313b22013-04-30 08:03:42 +0100297config ARCH_WANT_GENERAL_HUGETLB
298 def_bool y
299
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100300config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000301 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100302
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100303config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000304 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100305
Ingo Molnar765c68b2008-04-09 11:03:37 +0200306config ARCH_SUPPORTS_OPTIMIZED_INLINING
307 def_bool y
308
Akinobu Mita6a11f752009-03-31 15:23:17 -0700309config ARCH_SUPPORTS_DEBUG_PAGEALLOC
310 def_bool y
311
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300312config KASAN_SHADOW_OFFSET
313 hex
314 depends on KASAN
315 default 0xdffffc0000000000
316
Shane Wang69575d32009-09-01 18:25:07 -0700317config HAVE_INTEL_TXT
318 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700319 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700320
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100321config X86_32_SMP
322 def_bool y
323 depends on X86_32 && SMP
324
325config X86_64_SMP
326 def_bool y
327 depends on X86_64 && SMP
328
Tejun Heoccbeed32009-02-09 22:17:40 +0900329config X86_32_LAZY_GS
330 def_bool y
Masahiro Yamada8458f8c2018-06-14 19:36:43 +0900331 depends on X86_32 && !STACKPROTECTOR
Tejun Heoccbeed32009-02-09 22:17:40 +0900332
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530333config ARCH_SUPPORTS_UPROBES
334 def_bool y
335
Rob Herringd20642f2014-04-18 17:19:54 -0500336config FIX_EARLYCON_MEM
337 def_bool y
338
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +0300339config DYNAMIC_PHYSICAL_MASK
340 bool
341
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700342config PGTABLE_LEVELS
343 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300344 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700345 default 4 if X86_64
346 default 3 if X86_PAE
347 default 2
348
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100349source "init/Kconfig"
Masahiro Yamada2a61f472018-05-28 18:22:00 +0900350
351config CC_HAS_SANE_STACKPROTECTOR
352 bool
353 default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
354 default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
355 help
356 We have to make sure stack protector is unconditionally disabled if
357 the compiler produces broken code.
358
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700359source "kernel/Kconfig.freezer"
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100360
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100361menu "Processor type and features"
362
Randy Dunlap5ee71532012-01-16 11:57:18 -0800363config ZONE_DMA
364 bool "DMA memory allocation support" if EXPERT
365 default y
366 help
367 DMA memory allocation support allows devices with less than 32-bit
368 addressing to allocate within the first 16MB of address space.
369 Disable if no such devices will be used.
370
371 If unsure, say Y.
372
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100373config SMP
374 bool "Symmetric multi-processing support"
375 ---help---
376 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800377 a system with only one CPU, say N. If you have a system with more
378 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100379
Robert Graffham4a474152014-01-23 15:55:29 -0800380 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100381 machines, but will use only one CPU of a multiprocessor machine. If
382 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800383 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100384 will run faster if you say N here.
385
386 Note that if you say Y here and choose architecture "586" or
387 "Pentium" under "Processor family", the kernel will not work on 486
388 architectures. Similarly, multiprocessor kernels for the "PPro"
389 architecture may not work on all Pentium based boards.
390
391 People using multiprocessor machines who say Y here should also say
392 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
393 Management" code will be disabled if you say Y here.
394
Paul Bolle395cf962011-08-15 02:02:26 +0200395 See also <file:Documentation/x86/i386/IO-APIC.txt>,
Benjamin Petersonc9525a32017-05-20 17:20:16 -0700396 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100397 <http://www.tldp.org/docs.html#howto>.
398
399 If you don't know what to do here, say N.
400
Josh Triplett9def39be2013-10-30 08:09:45 -0700401config X86_FEATURE_NAMES
402 bool "Processor feature human-readable names" if EMBEDDED
403 default y
404 ---help---
405 This option compiles in a table of x86 feature bits and corresponding
406 names. This is required to support /proc/cpuinfo and a few kernel
407 messages. You can disable this to save space, at the expense of
408 making those few kernel messages show numeric feature bits instead.
409
410 If in doubt, say Y.
411
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800412config X86_X2APIC
413 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200414 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800415 ---help---
416 This enables x2apic support on CPUs that have this feature.
417
418 This allows 32-bit apic IDs (so it can support very large systems),
419 and accesses the local apic via MSRs not via mmio.
420
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800421 If you don't know what to do here, say N.
422
Yinghai Lu6695c852008-06-19 12:13:09 -0700423config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700424 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000425 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200426 depends on X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100427 ---help---
Yinghai Lu6695c852008-06-19 12:13:09 -0700428 For old smp systems that do not have proper acpi support. Newer systems
429 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700430
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000431config GOLDFISH
432 def_bool y
433 depends on X86_GOLDFISH
434
David Woodhouse76b04382018-01-11 21:46:25 +0000435config RETPOLINE
436 bool "Avoid speculative indirect branches in kernel"
437 default y
Peter Zijlstrad5028ba2018-02-06 09:46:13 +0100438 select STACK_VALIDATION if HAVE_STACK_VALIDATION
David Woodhouse76b04382018-01-11 21:46:25 +0000439 help
440 Compile kernel with the retpoline compiler options to guard against
441 kernel-to-user data leaks by avoiding speculative indirect
442 branches. Requires a compiler with -mindirect-branch=thunk-extern
443 support for full protection. The kernel may run slower.
444
445 Without compiler support, at least indirect branches in assembler
446 code are eliminated. Since this includes the syscall entry path,
447 it is not entirely pointless.
448
Vikas Shivappaf01d7d512017-07-25 14:14:22 -0700449config INTEL_RDT
450 bool "Intel Resource Director Technology support"
Fenghua Yu78e99b42016-10-22 06:19:53 -0700451 default n
452 depends on X86 && CPU_SUP_INTEL
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100453 select KERNFS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700454 help
Vikas Shivappaf01d7d512017-07-25 14:14:22 -0700455 Select to enable resource allocation and monitoring which are
456 sub-features of Intel Resource Director Technology(RDT). More
457 information about RDT can be found in the Intel x86
458 Architecture Software Developer Manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700459
460 Say N if unsure.
461
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800462if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800463config X86_BIGSMP
464 bool "Support for big SMP systems with more than 8 CPUs"
465 depends on SMP
466 ---help---
467 This option is needed for the systems that have more than 8 CPUs
468
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800469config X86_EXTENDED_PLATFORM
470 bool "Support for extended (non-PC) x86 platforms"
471 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100472 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100473 If you disable this option then the kernel will only support
474 standard PC platforms. (which covers the vast majority of
475 systems out there.)
476
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800477 If you enable this option then you'll be able to select support
478 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100479 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800480 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800481 RDC R-321x SoC
482 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200483 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200484 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100485
486 If you have one of these systems, or if you want to build a
487 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800488endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100489
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800490if X86_64
491config X86_EXTENDED_PLATFORM
492 bool "Support for extended (non-PC) x86 platforms"
493 default y
494 ---help---
495 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
499 If you enable this option then you'll be able to select support
500 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800501 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800502 ScaleMP vSMP
503 SGI Ultraviolet
504
505 If you have one of these systems, or if you want to build a
506 generic distribution kernel, say Y here - otherwise say N.
507endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800508# This is an alphabetically sorted list of 64 bit extended platforms
509# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800510config X86_NUMACHIP
511 bool "Numascale NumaChip"
512 depends on X86_64
513 depends on X86_EXTENDED_PLATFORM
514 depends on NUMA
515 depends on SMP
516 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700517 depends on PCI_MMCONFIG
Steffen Persvold44b111b52011-12-06 00:07:26 +0800518 ---help---
519 Adds support for Numascale NumaChip large-SMP systems. Needed to
520 enable more than ~168 cores.
521 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100522
Ingo Molnar6a485652009-01-27 18:29:13 +0100523config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800524 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100525 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100526 select PARAVIRT
527 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800528 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300529 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100530 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100531 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
532 supposed to run on these EM64T-based machines. Only choose this option
533 if you have one of these machines.
534
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800535config X86_UV
536 bool "SGI Ultraviolet"
537 depends on X86_64
538 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500539 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800540 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700541 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200542 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800543 ---help---
544 This option is needed in order to support SGI Ultraviolet systems.
545 If you don't have one of these, you should say N here.
546
547# Following is an alphabetically sorted list of 32 bit extended platforms
548# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100549
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000550config X86_GOLDFISH
551 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100552 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000553 ---help---
554 Enable support for the Goldfish virtual platform used primarily
555 for Android development. Unless you are building for the Android
556 Goldfish emulator say N here.
557
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800558config X86_INTEL_CE
559 bool "CE4100 TV platform"
560 depends on PCI
561 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800562 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800563 depends on X86_32
564 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800565 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100566 select OF
567 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800568 ---help---
569 Select for the Intel CE media processor (CE4100) SOC.
570 This option compiles in support for the CE4100 SOC for settop
571 boxes and media devices.
572
David Cohen4cb9b002013-12-16 17:37:26 -0800573config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100574 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100575 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800576 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000577 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200578 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000579 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000580 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800581 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000582 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000583 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000584 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000585 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000586 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800587 Select to build a kernel capable of supporting Intel MID (Mobile
588 Internet Device) platform systems which do not have the PCI legacy
589 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000590
David Cohen4cb9b002013-12-16 17:37:26 -0800591 Intel MID platforms are based on an Intel processor and chipset which
592 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100593
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000594config X86_INTEL_QUARK
595 bool "Intel Quark platform support"
596 depends on X86_32
597 depends on X86_EXTENDED_PLATFORM
598 depends on X86_PLATFORM_DEVICES
599 depends on X86_TSC
600 depends on PCI
601 depends on PCI_GOANY
602 depends on X86_IO_APIC
603 select IOSF_MBI
604 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200605 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000606 ---help---
607 Select to include support for Quark X1000 SoC.
608 Say Y here if you have a Quark based system such as the Arduino
609 compatible Intel Galileo.
610
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000611config X86_INTEL_LPSS
612 bool "Intel Low Power Subsystem Support"
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100613 depends on X86 && ACPI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000614 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300615 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100616 select IOSF_MBI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000617 ---help---
618 Select to build support for Intel Low Power Subsystem such as
619 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300620 things like clock tree (common clock framework) and pincontrol
621 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000622
Ken Xue92082a82015-02-06 08:27:51 +0800623config X86_AMD_PLATFORM_DEVICE
624 bool "AMD ACPI2Platform devices support"
625 depends on ACPI
626 select COMMON_CLK
627 select PINCTRL
628 ---help---
629 Select to interpret AMD specific ACPI device to platform device
630 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
631 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
632 implemented under PINCTRL subsystem.
633
David E. Boxced3ce72014-09-17 22:13:50 -0700634config IOSF_MBI
635 tristate "Intel SoC IOSF Sideband support for SoC platforms"
636 depends on PCI
637 ---help---
638 This option enables sideband register access support for Intel SoC
639 platforms. On these platforms the IOSF sideband is used in lieu of
640 MSR's for some register accesses, mostly but not limited to thermal
641 and power. Drivers may query the availability of this device to
642 determine if they need the sideband in order to work on these
643 platforms. The sideband is available on the following SoC products.
644 This list is not meant to be exclusive.
645 - BayTrail
646 - Braswell
647 - Quark
648
649 You should say Y if you are running a kernel on one of these SoC's.
650
David E. Boxed2226b2014-09-17 22:13:51 -0700651config IOSF_MBI_DEBUG
652 bool "Enable IOSF sideband access through debugfs"
653 depends on IOSF_MBI && DEBUG_FS
654 ---help---
655 Select this option to expose the IOSF sideband access registers (MCR,
656 MDR, MCRX) through debugfs to write and read register information from
657 different units on the SoC. This is most useful for obtaining device
658 state information for debug and analysis. As this is a general access
659 mechanism, users of this option would have specific knowledge of the
660 device they want to access.
661
662 If you don't require the option or are in doubt, say N.
663
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800664config X86_RDC321X
665 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100666 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800667 depends on X86_EXTENDED_PLATFORM
668 select M486
669 select X86_REBOOTFIXUPS
670 ---help---
671 This option is needed for RDC R-321x system-on-chip, also known
672 as R-8610-(G).
673 If you don't have one of these chips, you should say N here.
674
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100675config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100676 bool "Support non-standard 32-bit SMP architectures"
677 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800678 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100679 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800680 This option compiles in the bigsmp and STA2X11 default
681 subarchitectures. It is intended for a generic binary
682 kernel. If you select them all, kernel will probe it one by
683 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700684
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800685# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700686
Linus Torvaldsd949f362009-09-26 09:35:07 -0700687config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100688 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700689 # MCE code calls memory_failure():
690 depends on X86_MCE
691 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700692 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
693 depends on X86_64 || !SPARSEMEM
694 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700695
Alessandro Rubini83125a32012-04-04 19:40:21 +0200696config STA2X11
697 bool "STA2X11 Companion Chip Support"
698 depends on X86_32_NON_STANDARD && PCI
Christoph Hellwigb6e05472018-03-19 11:38:24 +0100699 select ARCH_HAS_PHYS_TO_DMA
Alessandro Rubini83125a32012-04-04 19:40:21 +0200700 select X86_DEV_DMA_OPS
701 select X86_DMA_REMAP
702 select SWIOTLB
703 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200704 select GPIOLIB
Alessandro Rubini83125a32012-04-04 19:40:21 +0200705 default n
706 ---help---
707 This adds support for boards based on the STA2X11 IO-Hub,
708 a.k.a. "ConneXt". The chip is used in place of the standard
709 PC chipset, so all "standard" peripherals are missing. If this
710 option is selected the kernel will still be able to boot on
711 standard PC machines.
712
Shérab82148d12010-09-25 06:06:57 +0200713config X86_32_IRIS
714 tristate "Eurobraille/Iris poweroff module"
715 depends on X86_32
716 ---help---
717 The Iris machines from EuroBraille do not have APM or ACPI support
718 to shut themselves down properly. A special I/O sequence is
719 needed to do so, which is what this module does at
720 kernel shutdown.
721
722 This is only for Iris machines from EuroBraille.
723
724 If unused, say N.
725
Ingo Molnarae1e9132008-11-11 09:05:16 +0100726config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100727 def_bool y
728 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800729 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100730 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100731 Calculate simpler /proc/<PID>/wchan values. If this option
732 is disabled then wchan values will recurse back to the
733 caller function. This provides more accurate wchan values,
734 at the expense of slightly more scheduling overhead.
735
736 If in doubt, say "Y".
737
Borislav Petkov6276a072013-03-04 21:20:21 +0100738menuconfig HYPERVISOR_GUEST
739 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100740 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100741 Say Y here to enable options for running Linux under various hyper-
742 visors. This option enables basic hypervisor detection and platform
743 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100744
Borislav Petkov6276a072013-03-04 21:20:21 +0100745 If you say N, all options in this submenu will be skipped and
746 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100747
Borislav Petkov6276a072013-03-04 21:20:21 +0100748if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100749
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100750config PARAVIRT
751 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100752 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100753 This changes the kernel so it can modify itself when it is run
754 under a hypervisor, potentially improving performance significantly
755 over full virtualization. However, when run without a hypervisor
756 the kernel is theoretically slower and slightly larger.
757
Borislav Petkov6276a072013-03-04 21:20:21 +0100758config PARAVIRT_DEBUG
759 bool "paravirt-ops debugging"
760 depends on PARAVIRT && DEBUG_KERNEL
761 ---help---
762 Enable to debug paravirt_ops internals. Specifically, BUG if
763 a paravirt_op is missing when it is called.
764
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700765config PARAVIRT_SPINLOCKS
766 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700767 depends on PARAVIRT && SMP
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700768 ---help---
769 Paravirtualized spinlocks allow a pvops backend to replace the
770 spinlock implementation with something virtualization-friendly
771 (for example, block the virtual CPU rather than spinning).
772
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530773 It has a minimal impact on native kernels and gives a nice performance
774 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700775
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530776 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700777
Waiman Long45e898b2015-11-09 19:09:25 -0500778config QUEUED_LOCK_STAT
779 bool "Paravirt queued spinlock statistics"
Peter Zijlstracfd89832016-05-18 20:43:02 +0200780 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
Waiman Long45e898b2015-11-09 19:09:25 -0500781 ---help---
782 Enable the collection of statistical data on the slowpath
783 behavior of paravirtualized queued spinlocks and report
784 them on debugfs.
785
Borislav Petkov6276a072013-03-04 21:20:21 +0100786source "arch/x86/xen/Kconfig"
787
788config KVM_GUEST
789 bool "KVM Guest support (including kvmclock)"
790 depends on PARAVIRT
791 select PARAVIRT_CLOCK
792 default y
793 ---help---
794 This option enables various optimizations for running under the KVM
795 hypervisor. It includes a paravirtualized clock, so that instead
796 of relying on a PIT (or probably other) emulation by the
797 underlying device model, the host provides the guest with
798 timing infrastructure such as time of day, and system time
799
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530800config KVM_DEBUG_FS
801 bool "Enable debug information for KVM Guests in debugfs"
802 depends on KVM_GUEST && DEBUG_FS
803 default n
804 ---help---
805 This option enables collection of various statistics for KVM guest.
806 Statistics are displayed in debugfs filesystem. Enabling this option
807 may incur significant overhead.
808
Borislav Petkov6276a072013-03-04 21:20:21 +0100809config PARAVIRT_TIME_ACCOUNTING
810 bool "Paravirtual steal time accounting"
811 depends on PARAVIRT
812 default n
813 ---help---
814 Select this option to enable fine granularity task steal time
815 accounting. Time spent executing other tasks in parallel with
816 the current vCPU is discounted from the vCPU power. To account for
817 that, there can be a small performance impact.
818
819 If in doubt, say N here.
820
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200821config PARAVIRT_CLOCK
822 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200823
Jan Kiszka4a362602017-11-27 09:11:46 +0100824config JAILHOUSE_GUEST
825 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100826 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100827 select X86_PM_TIMER
Jan Kiszka4a362602017-11-27 09:11:46 +0100828 ---help---
829 This option allows to run Linux as guest in a Jailhouse non-root
830 cell. You can leave this option disabled if you only want to start
831 Jailhouse and run Linux afterwards in the root cell.
832
Borislav Petkov6276a072013-03-04 21:20:21 +0100833endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400834
Yinghai Lu08677212010-02-10 01:20:20 -0800835config NO_BOOTMEM
Yinghai Lu774ea0b2010-08-25 13:39:18 -0700836 def_bool y
Yinghai Lu08677212010-02-10 01:20:20 -0800837
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100838source "arch/x86/Kconfig.cpu"
839
840config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100841 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100842 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100843 ---help---
844 Use the IA-PC HPET (High Precision Event Timer) to manage
845 time in preference to the PIT and RTC, if a HPET is
846 present.
847 HPET is the next generation timer replacing legacy 8254s.
848 The HPET provides a stable time base on SMP
849 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200850 as it is off-chip. The interface used is documented
851 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100852
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100853 You can safely choose Y here. However, HPET will only be
854 activated if the platform and the BIOS support this feature.
855 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100856
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100857 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100858
859config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100860 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800861 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100862
Jacob Panbb24c472009-09-02 07:37:17 -0700863config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000864 def_bool y if X86_INTEL_MID
865 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100866 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000867 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700868 help
869 APB timer is the replacement for 8254, HPET on X86 MID platforms.
870 The APBT provides a stable time base on SMP
871 systems, unlike the TSC, but it is more expensive to access,
872 as it is off-chip. APB timers are always running regardless of CPU
873 C states, they are used as per CPU clockevent device when possible.
874
David Rientjes6a108a12011-01-20 14:44:16 -0800875# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100876# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700877config DMI
878 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800879 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800880 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100881 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700882 Enabled scanning of DMI to identify machine quirks. Say Y
883 here unless you have verified that your setup is not
884 affected by entries in the DMI blacklist. Required by PNP
885 BIOS code.
886
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100887config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700888 bool "Old AMD GART IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200889 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100890 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200891 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100892 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200893 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
894 GART based hardware IOMMUs.
895
896 The GART supports full DMA access for devices with 32-bit access
897 limitations, on systems with more than 3 GB. This is usually needed
898 for USB, sound, many IDE/SATA chipsets and some other devices.
899
900 Newer systems typically have a modern AMD IOMMU, supported via
901 the CONFIG_AMD_IOMMU=y config option.
902
903 In normal configurations this driver is only active when needed:
904 there's more than 3 GB of memory and the system contains a
905 32-bit limited device.
906
907 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100908
909config CALGARY_IOMMU
910 bool "IBM Calgary IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200911 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100912 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700913 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100914 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100915 Support for hardware IOMMUs in IBM's xSeries x366 and x460
916 systems. Needed to run systems with more than 3GB of memory
917 properly with 32-bit PCI devices that do not support DAC
918 (Double Address Cycle). Calgary also supports bus level
919 isolation, where all DMAs pass through the IOMMU. This
920 prevents them from going anywhere except their intended
921 destination. This catches hard-to-find kernel bugs and
922 mis-behaving drivers and devices that do not use the DMA-API
923 properly to set up their DMA buffers. The IOMMU can be
924 turned off at boot time with the iommu=off parameter.
925 Normally the kernel will make the right choice by itself.
926 If unsure, say Y.
927
928config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100929 def_bool y
930 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100931 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100932 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100933 Should Calgary be enabled by default? if you choose 'y', Calgary
934 will be used (if it exists). If you choose 'n', Calgary will not be
935 used even if it exists. If you choose 'n' and would like to use
936 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
937 If unsure, say Y.
938
Mike Travis1184dc22008-05-12 21:21:12 +0200939config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200940 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700941 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800942 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100943 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200944 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200945 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100946
Ingo Molnaraec64872018-02-10 12:36:29 +0100947#
948# The maximum number of CPUs supported:
949#
950# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
951# and which can be configured interactively in the
952# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
953#
954# The ranges are different on 32-bit and 64-bit kernels, depending on
955# hardware capabilities and scalability features of the kernel.
956#
957# ( If MAXSMP is enabled we just use the highest possible value and disable
958# interactive configuration. )
959#
960
961config NR_CPUS_RANGE_BEGIN
962 int
963 default NR_CPUS_RANGE_END if MAXSMP
964 default 1 if !SMP
965 default 2
966
967config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800968 int
969 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100970 default 64 if SMP && X86_BIGSMP
971 default 8 if SMP && !X86_BIGSMP
972 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800973
Ingo Molnaraec64872018-02-10 12:36:29 +0100974config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800975 int
976 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100977 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
978 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
979 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800980
Ingo Molnaraec64872018-02-10 12:36:29 +0100981config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800982 int
983 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100984 default 32 if X86_BIGSMP
985 default 8 if SMP
986 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800987
Ingo Molnaraec64872018-02-10 12:36:29 +0100988config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800989 int
990 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100991 default 8192 if MAXSMP
992 default 64 if SMP
993 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800994
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100995config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800996 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +0100997 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
998 default NR_CPUS_DEFAULT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100999 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001000 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -05001001 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +03001002 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001003 minimum value which makes sense is 2.
1004
Ingo Molnaraec64872018-02-10 12:36:29 +01001005 This is purely to save memory: each supported CPU adds about 8KB
1006 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001007
1008config SCHED_SMT
1009 bool "SMT (Hyperthreading) scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001010 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001011 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001012 SMT scheduler support improves the CPU scheduler's decision making
1013 when dealing with Intel Pentium 4 chips with HyperThreading at a
1014 cost of slightly increased overhead in some places. If unsure say
1015 N here.
1016
1017config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001018 def_bool y
1019 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001020 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001021 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001022 Multi-core scheduler support improves the CPU scheduler's decision
1023 making when dealing with multi-core CPU chips at a cost of slightly
1024 increased overhead in some places. If unsure say N here.
1025
Tim Chende966cf2016-11-29 10:43:27 -08001026config SCHED_MC_PRIO
1027 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001028 depends on SCHED_MC && CPU_SUP_INTEL
1029 select X86_INTEL_PSTATE
1030 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001031 default y
Tim Chen5e76b2a2016-11-22 12:23:55 -08001032 ---help---
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001033 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1034 core ordering determined at manufacturing time, which allows
1035 certain cores to reach higher turbo frequencies (when running
1036 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001037
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001038 Enabling this kernel feature teaches the scheduler about
1039 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1040 scheduler's CPU selection logic accordingly, so that higher
1041 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001042
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001043 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001044
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001045 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001046
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001047source "kernel/Kconfig.preempt"
1048
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001049config UP_LATE_INIT
1050 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +01001051 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001052
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001053config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001054 bool "Local APIC support on uniprocessors" if !PCI_MSI
1055 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001056 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001057 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001058 A local APIC (Advanced Programmable Interrupt Controller) is an
1059 integrated interrupt controller in the CPU. If you have a single-CPU
1060 system which has a processor with a local APIC, you can say Y here to
1061 enable and use it. If you say Y here even though your machine doesn't
1062 have a local APIC, then the kernel will still run with no slowdown at
1063 all. The local APIC supports CPU-generated self-interrupts (timer,
1064 performance counters), and the NMI watchdog which detects hard
1065 lockups.
1066
1067config X86_UP_IOAPIC
1068 bool "IO-APIC support on uniprocessors"
1069 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001070 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001071 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1072 SMP-capable replacement for PC-style interrupt controllers. Most
1073 SMP systems and many recent uniprocessor systems have one.
1074
1075 If you have a single-CPU system with an IO-APIC, you can say Y here
1076 to use it. If you say Y here even though your machine doesn't have
1077 an IO-APIC, then the kernel will still run with no slowdown at all.
1078
1079config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001080 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001081 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001082 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001083 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001084
1085config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001086 def_bool y
1087 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001088
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001089config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1090 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001091 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001092 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001093 This option enables a workaround that fixes a source of
1094 spurious interrupts. This is recommended when threaded
1095 interrupt handling is used on systems where the generation of
1096 superfluous "boot interrupts" cannot be disabled.
1097
1098 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1099 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1100 kernel does during interrupt handling). On chipsets where this
1101 boot IRQ generation cannot be disabled, this workaround keeps
1102 the original IRQ line masked so that only the equivalent "boot
1103 IRQ" is delivered to the CPUs. The workaround also tells the
1104 kernel to set up the IRQ handler on the boot IRQ line. In this
1105 way only one interrupt is delivered to the kernel. Otherwise
1106 the spurious second interrupt may cause the kernel to bring
1107 down (vital) interrupt lines.
1108
1109 Only affects "broken" chipsets. Interrupt sharing may be
1110 increased on these systems.
1111
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001112config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001113 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001114 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001115 default y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001116 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +02001117 Machine Check support allows the processor to notify the
1118 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001119 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001120 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001121
Tony Luck5de97c92017-03-27 11:33:03 +02001122config X86_MCELOG_LEGACY
1123 bool "Support for deprecated /dev/mcelog character device"
1124 depends on X86_MCE
1125 ---help---
1126 Enable support for /dev/mcelog which is needed by the old mcelog
1127 userspace logging daemon. Consider switching to the new generation
1128 rasdaemon solution.
1129
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001130config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001131 def_bool y
1132 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001133 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001134 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001135 Additional support for intel specific MCE features such as
1136 the thermal monitor.
1137
1138config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001139 def_bool y
1140 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001141 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001142 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001143 Additional support for AMD specific MCE features such as
1144 the DRAM Error Threshold.
1145
Andi Kleen4efc0672009-04-28 19:07:31 +02001146config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001147 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001148 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001149 ---help---
1150 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001151 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001152 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001153
Andi Kleenb2762682009-02-12 13:49:31 +01001154config X86_MCE_THRESHOLD
1155 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001156 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001157
Andi Kleenea149b32009-04-29 19:31:00 +02001158config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001159 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001160 tristate "Machine check injector support"
1161 ---help---
1162 Provide support for injecting machine checks for testing purposes.
1163 If you don't know what a machine check is and you don't do kernel
1164 QA it is safe to say n.
1165
Andi Kleen4efc0672009-04-28 19:07:31 +02001166config X86_THERMAL_VECTOR
1167 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001168 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001169
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001170source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001171
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001172config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001173 bool "Legacy VM86 support"
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001174 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001175 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001176 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001177 This option allows user programs to put the CPU into V8086
1178 mode, which is an 80286-era approximation of 16-bit real mode.
1179
1180 Some very old versions of X and/or vbetool require this option
1181 for user mode setting. Similarly, DOSEMU will use it if
1182 available to accelerate real mode DOS programs. However, any
1183 recent version of DOSEMU, X, or vbetool should be fully
1184 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001185 fall back to software emulation. Nevertheless, if you are using
1186 a 16-bit DOS program where 16-bit performance matters, vm86
1187 mode might be faster than emulation and you might want to
1188 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001189
Ingo Molnar1e642812015-09-05 08:58:10 +02001190 Note that any app that works on a 64-bit kernel is unlikely to
1191 need this option, as 64-bit kernels don't, and can't, support
1192 V8086 mode. This option is also unrelated to 16-bit protected
1193 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001194
Ingo Molnar1e642812015-09-05 08:58:10 +02001195 Enabling this option increases the complexity of the kernel
1196 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001197
Ingo Molnar1e642812015-09-05 08:58:10 +02001198 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001199
1200config VM86
1201 bool
1202 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001203
1204config X86_16BIT
1205 bool "Enable support for 16-bit segments" if EXPERT
1206 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001207 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001208 ---help---
1209 This option is required by programs like Wine to run 16-bit
1210 protected mode legacy code on x86 processors. Disabling
1211 this option saves about 300 bytes on i386, or around 6K text
1212 plus 16K runtime memory on x86-64,
1213
1214config X86_ESPFIX32
1215 def_bool y
1216 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001217
H. Peter Anvin197725d2014-05-04 10:00:49 -07001218config X86_ESPFIX64
1219 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001220 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001221
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001222config X86_VSYSCALL_EMULATION
1223 bool "Enable vsyscall emulation" if EXPERT
1224 default y
1225 depends on X86_64
1226 ---help---
1227 This enables emulation of the legacy vsyscall page. Disabling
1228 it is roughly equivalent to booting with vsyscall=none, except
1229 that it will also disable the helpful warning if a program
1230 tries to use a vsyscall. With this option set to N, offending
1231 programs will just segfault, citing addresses of the form
1232 0xffffffffff600?00.
1233
1234 This option is required by many programs built before 2013, and
1235 care should be used even with newer programs if set to N.
1236
1237 Disabling this option saves about 7K of kernel size and
1238 possibly 4K of additional runtime pagetable memory.
1239
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001240config TOSHIBA
1241 tristate "Toshiba Laptop support"
1242 depends on X86_32
1243 ---help---
1244 This adds a driver to safely access the System Management Mode of
1245 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1246 not work on models with a Phoenix BIOS. The System Management Mode
1247 is used to set the BIOS and power saving options on Toshiba portables.
1248
1249 For information on utilities to make use of this driver see the
1250 Toshiba Linux utilities web site at:
1251 <http://www.buzzard.org.uk/toshiba/>.
1252
1253 Say Y if you intend to run this kernel on a Toshiba portable.
1254 Say N otherwise.
1255
1256config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001257 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001258 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001259 select SENSORS_DELL_SMM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001260 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001261 This option enables legacy /proc/i8k userspace interface in hwmon
1262 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1263 temperature and allows controlling fan speeds of Dell laptops via
1264 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1265 it reports also power and hotkey status. For fan speed control is
1266 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001267
Pali Rohár039ae582015-05-14 13:16:37 +02001268 Say Y if you intend to run this kernel on old Dell laptops or want to
1269 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001270 Say N otherwise.
1271
1272config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001273 bool "Enable X86 board specific fixups for reboot"
1274 depends on X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001275 ---help---
1276 This enables chipset and/or board specific fixups to be done
1277 in order to get reboot to work correctly. This is only needed on
1278 some combinations of hardware and BIOS. The symptom, for which
1279 this config is intended, is when reboot ends with a stalled/hung
1280 system.
1281
1282 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001283 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001284
1285 Say Y if you want to enable the fixup. Currently, it's safe to
1286 enable this option even if you don't need it.
1287 Say N otherwise.
1288
1289config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001290 bool "CPU microcode loading support"
1291 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001292 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001293 select FW_LOADER
1294 ---help---
1295 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001296 Intel and AMD processors. The Intel support is for the IA32 family,
1297 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1298 AMD support is for families 0x10 and later. You will obviously need
1299 the actual microcode binary data itself which is not shipped with
1300 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001301
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001302 The preferred method to load microcode from a detached initrd is described
Jaak Ristioja1897a962018-02-09 11:22:16 +02001303 in Documentation/x86/microcode.txt. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001304 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1305 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001306
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001307 In addition, you can build the microcode into the kernel. For that you
1308 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1309 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001310
Peter Oruba8d86f392008-07-28 18:44:21 +02001311config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001312 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001313 depends on MICROCODE
1314 default MICROCODE
1315 select FW_LOADER
1316 ---help---
1317 This options enables microcode patch loading support for Intel
1318 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001319
Alanb8989db2014-01-20 18:01:56 +00001320 For the current Intel microcode data package go to
1321 <https://downloadcenter.intel.com> and search for
1322 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001323
Peter Oruba80cc9f12008-07-28 18:44:22 +02001324config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001325 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001326 depends on MICROCODE
1327 select FW_LOADER
1328 ---help---
1329 If you select this option, microcode patch loading support for AMD
1330 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001331
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001332config MICROCODE_OLD_INTERFACE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001333 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001334 depends on MICROCODE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001335
1336config X86_MSR
1337 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001338 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001339 This device gives privileged processes access to the x86
1340 Model-Specific Registers (MSRs). It is a character device with
1341 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1342 MSR accesses are directed to a specific CPU on multi-processor
1343 systems.
1344
1345config X86_CPUID
1346 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001347 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001348 This device gives processes access to the x86 CPUID instruction to
1349 be executed on a specific processor. It is a character device
1350 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1351 /dev/cpu/31/cpuid.
1352
1353choice
1354 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001355 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001356 depends on X86_32
1357
1358config NOHIGHMEM
1359 bool "off"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001360 ---help---
1361 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1362 However, the address space of 32-bit x86 processors is only 4
1363 Gigabytes large. That means that, if you have a large amount of
1364 physical memory, not all of it can be "permanently mapped" by the
1365 kernel. The physical memory that's not permanently mapped is called
1366 "high memory".
1367
1368 If you are compiling a kernel which will never run on a machine with
1369 more than 1 Gigabyte total physical RAM, answer "off" here (default
1370 choice and suitable for most users). This will result in a "3GB/1GB"
1371 split: 3GB are mapped so that each process sees a 3GB virtual memory
1372 space and the remaining part of the 4GB virtual memory space is used
1373 by the kernel to permanently map as much physical memory as
1374 possible.
1375
1376 If the machine has between 1 and 4 Gigabytes physical RAM, then
1377 answer "4GB" here.
1378
1379 If more than 4 Gigabytes is used then answer "64GB" here. This
1380 selection turns Intel PAE (Physical Address Extension) mode on.
1381 PAE implements 3-level paging on IA32 processors. PAE is fully
1382 supported by Linux, PAE mode is implemented on all recent Intel
1383 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1384 then the kernel will not boot on CPUs that don't support PAE!
1385
1386 The actual amount of total physical memory will either be
1387 auto detected or can be forced by using a kernel command line option
1388 such as "mem=256M". (Try "man bootparam" or see the documentation of
1389 your boot loader (lilo or loadlin) about how to pass options to the
1390 kernel at boot time.)
1391
1392 If unsure, say "off".
1393
1394config HIGHMEM4G
1395 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001396 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001397 Select this if you have a 32-bit processor and between 1 and 4
1398 gigabytes of physical RAM.
1399
1400config HIGHMEM64G
1401 bool "64GB"
Matthew Whitehead69b8d3f2018-02-15 11:54:55 -05001402 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001403 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001404 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001405 Select this if you have a 32-bit processor and more than 4
1406 gigabytes of physical RAM.
1407
1408endchoice
1409
1410choice
David Rientjes6a108a12011-01-20 14:44:16 -08001411 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001412 default VMSPLIT_3G
1413 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001414 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001415 Select the desired split between kernel and user memory.
1416
1417 If the address range available to the kernel is less than the
1418 physical memory installed, the remaining memory will be available
1419 as "high memory". Accessing high memory is a little more costly
1420 than low memory, as it needs to be mapped into the kernel first.
1421 Note that increasing the kernel address space limits the range
1422 available to user programs, making the address space there
1423 tighter. Selecting anything other than the default 3G/1G split
1424 will also likely make your kernel incompatible with binary-only
1425 kernel modules.
1426
1427 If you are not absolutely sure what you are doing, leave this
1428 option alone!
1429
1430 config VMSPLIT_3G
1431 bool "3G/1G user/kernel split"
1432 config VMSPLIT_3G_OPT
1433 depends on !X86_PAE
1434 bool "3G/1G user/kernel split (for full 1G low memory)"
1435 config VMSPLIT_2G
1436 bool "2G/2G user/kernel split"
1437 config VMSPLIT_2G_OPT
1438 depends on !X86_PAE
1439 bool "2G/2G user/kernel split (for full 2G low memory)"
1440 config VMSPLIT_1G
1441 bool "1G/3G user/kernel split"
1442endchoice
1443
1444config PAGE_OFFSET
1445 hex
1446 default 0xB0000000 if VMSPLIT_3G_OPT
1447 default 0x80000000 if VMSPLIT_2G
1448 default 0x78000000 if VMSPLIT_2G_OPT
1449 default 0x40000000 if VMSPLIT_1G
1450 default 0xC0000000
1451 depends on X86_32
1452
1453config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001454 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001455 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001456
1457config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001458 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001459 depends on X86_32 && !HIGHMEM4G
Christoph Hellwigd4a451d2018-04-03 16:24:20 +02001460 select PHYS_ADDR_T_64BIT
Christian Melki9d99c712015-10-05 17:31:33 +02001461 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001462 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001463 PAE is required for NX support, and furthermore enables
1464 larger swapspace support for non-overcommit purposes. It
1465 has the cost of more pagetable lookup overhead, and also
1466 consumes more pagetable space per process.
1467
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001468config X86_5LEVEL
1469 bool "Enable 5-level page tables support"
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001470 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001471 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001472 depends on X86_64
1473 ---help---
1474 5-level paging enables access to larger address space:
1475 upto 128 PiB of virtual address space and 4 PiB of
1476 physical address space.
1477
1478 It will be supported by future Intel CPUs.
1479
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001480 A kernel with the option enabled can be booted on machines that
1481 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001482
1483 See Documentation/x86/x86_64/5level-paging.txt for more
1484 information.
1485
1486 Say N if unsure.
1487
Ingo Molnar10971ab2015-03-05 08:18:23 +01001488config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001489 def_bool y
Levin, Alexander (Sasha Levin)4675ff02017-11-15 17:36:02 -08001490 depends on X86_64 && !DEBUG_PAGEALLOC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001491 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001492 Certain kernel features effectively disable kernel
1493 linear 1 GB mappings (even if the CPU otherwise
1494 supports them), so don't confuse the user by printing
1495 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001496
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001497config ARCH_HAS_MEM_ENCRYPT
1498 def_bool y
1499
1500config AMD_MEM_ENCRYPT
1501 bool "AMD Secure Memory Encryption (SME) support"
1502 depends on X86_64 && CPU_SUP_AMD
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +03001503 select DYNAMIC_PHYSICAL_MASK
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001504 ---help---
1505 Say yes to enable support for the encryption of system memory.
1506 This requires an AMD processor that supports Secure Memory
1507 Encryption (SME).
1508
1509config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1510 bool "Activate AMD Secure Memory Encryption (SME) by default"
1511 default y
1512 depends on AMD_MEM_ENCRYPT
1513 ---help---
1514 Say yes to have system memory encrypted by default if running on
1515 an AMD processor that supports Secure Memory Encryption (SME).
1516
1517 If set to Y, then the encryption of system memory can be
1518 deactivated with the mem_encrypt=off command line option.
1519
1520 If set to N, then the encryption of system memory can be
1521 activated with the mem_encrypt=on command line option.
1522
Tom Lendackyf88a68f2017-07-17 16:10:09 -05001523config ARCH_USE_MEMREMAP_PROT
1524 def_bool y
1525 depends on AMD_MEM_ENCRYPT
1526
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001527# Common NUMA Features
1528config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001529 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001530 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001531 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1532 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001533 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001534 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001535
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001536 The kernel will try to allocate memory used by a CPU on the
1537 local memory controller of the CPU and add some more
1538 NUMA awareness to the kernel.
1539
Ingo Molnarc280ea52008-11-08 13:29:45 +01001540 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001541 (or later), AMD Opteron, or EM64T NUMA.
1542
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001543 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001544 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001545
1546 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001547
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001548config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001549 def_bool y
1550 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001551 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001552 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001553 Enable AMD NUMA node topology detection. You should say Y here if
1554 you have a multi processor AMD system. This uses an old method to
1555 read the NUMA configuration directly from the builtin Northbridge
1556 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1557 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001558
1559config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001560 def_bool y
1561 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001562 depends on X86_64 && NUMA && ACPI && PCI
1563 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001564 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001565 Enable ACPI SRAT based node topology detection.
1566
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001567# Some NUMA nodes have memory ranges that span
1568# other nodes. Even though a pfn is valid and
1569# between a node's start and end pfns, it may not
1570# reside on that node. See memmap_init_zone()
1571# for details.
1572config NODES_SPAN_OTHER_NODES
1573 def_bool y
1574 depends on X86_64_ACPI_NUMA
1575
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001576config NUMA_EMU
1577 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001578 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001579 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001580 Enable NUMA emulation. A flat machine will be split
1581 into virtual nodes when booted with "numa=fake=N", where N is the
1582 number of nodes. This is only useful for debugging.
1583
1584config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001585 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001586 range 1 10
1587 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001588 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001589 default "3"
1590 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001591 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001592 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001593 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001594
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001595config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001596 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001597 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001598
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001599config ARCH_FLATMEM_ENABLE
1600 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001601 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001602
1603config ARCH_DISCONTIGMEM_ENABLE
1604 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001605 depends on NUMA && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001606
1607config ARCH_DISCONTIGMEM_DEFAULT
1608 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001609 depends on NUMA && X86_32
1610
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001611config ARCH_SPARSEMEM_ENABLE
1612 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001613 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001614 select SPARSEMEM_STATIC if X86_32
1615 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1616
Tejun Heo3b166512011-04-01 11:15:12 +02001617config ARCH_SPARSEMEM_DEFAULT
1618 def_bool y
1619 depends on X86_64
1620
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001621config ARCH_SELECT_MEMORY_MODEL
1622 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001623 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001624
1625config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001626 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001627 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001628 help
1629 This option enables a sysfs memory/probe interface for testing.
1630 See Documentation/memory-hotplug.txt for more information.
1631 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001632
Tejun Heo3b166512011-04-01 11:15:12 +02001633config ARCH_PROC_KCORE_TEXT
1634 def_bool y
1635 depends on X86_64 && PROC_KCORE
1636
Avi Kivitya29815a2010-01-10 16:28:09 +02001637config ILLEGAL_POINTER_VALUE
1638 hex
1639 default 0 if X86_32
1640 default 0xdead000000000000 if X86_64
1641
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001642source "mm/Kconfig"
1643
Dan Williams7a678322015-08-19 00:34:34 -04001644config X86_PMEM_LEGACY_DEVICE
1645 bool
1646
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001647config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001648 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001649 depends on PHYS_ADDR_T_64BIT
1650 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001651 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001652 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001653 help
1654 Treat memory marked using the non-standard e820 type of 12 as used
1655 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1656 The kernel will offer these regions to the 'pmem' driver so
1657 they can be used for persistent storage.
1658
1659 Say Y if unsure.
1660
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001661config HIGHPTE
1662 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001663 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001664 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001665 The VM uses one page table entry for each page of physical memory.
1666 For systems with a lot of RAM, this can be wasteful of precious
1667 low memory. Setting this option will put user-space page table
1668 entries in high memory.
1669
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001670config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001671 bool "Check for low memory corruption"
1672 ---help---
1673 Periodically check for memory corruption in low memory, which
1674 is suspected to be caused by BIOS. Even when enabled in the
1675 configuration, it is disabled at runtime. Enable it by
1676 setting "memory_corruption_check=1" on the kernel command
1677 line. By default it scans the low 64k of memory every 60
1678 seconds; see the memory_corruption_check_size and
1679 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001680 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001681
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001682 When enabled with the default parameters, this option has
1683 almost no overhead, as it reserves a relatively small amount
1684 of memory and scans it infrequently. It both detects corruption
1685 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001686
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001687 It is, however, intended as a diagnostic tool; if repeatable
1688 BIOS-originated corruption always affects the same memory,
1689 you can use memmap= to prevent the kernel from using that
1690 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001691
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001692config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001693 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001694 depends on X86_CHECK_BIOS_CORRUPTION
1695 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001696 ---help---
1697 Set whether the default state of memory_corruption_check is
1698 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001699
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001700config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001701 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1702 default 64
1703 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001704 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001705 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001706
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001707 The first page contains BIOS data structures that the kernel
1708 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001709
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001710 By default we reserve the first 64K of physical RAM, as a
1711 number of BIOSes are known to corrupt that memory range
1712 during events such as suspend/resume or monitor cable
1713 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001714
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001715 You can set this to 4 if you are absolutely sure that you
1716 trust the BIOS to get all its memory reservations and usages
1717 right. If you know your BIOS have problems beyond the
1718 default 64K area, you can set this to 640 to avoid using the
1719 entire low memory range.
1720
1721 If you have doubts about the BIOS (e.g. suspend/resume does
1722 not work or there's kernel crashes after certain hardware
1723 hotplug events) then you might want to enable
1724 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1725 typical corruption patterns.
1726
1727 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001728
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001729config MATH_EMULATION
1730 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001731 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001732 prompt "Math emulation" if X86_32
1733 ---help---
1734 Linux can emulate a math coprocessor (used for floating point
1735 operations) if you don't have one. 486DX and Pentium processors have
1736 a math coprocessor built in, 486SX and 386 do not, unless you added
1737 a 487DX or 387, respectively. (The messages during boot time can
1738 give you some hints here ["man dmesg"].) Everyone needs either a
1739 coprocessor or this emulation.
1740
1741 If you don't have a math coprocessor, you need to say Y here; if you
1742 say Y here even though you have a coprocessor, the coprocessor will
1743 be used nevertheless. (This behavior can be changed with the kernel
1744 command line option "no387", which comes handy if your coprocessor
1745 is broken. Try "man bootparam" or see the documentation of your boot
1746 loader (lilo or loadlin) about how to pass options to the kernel at
1747 boot time.) This means that it is a good idea to say Y here if you
1748 intend to use this kernel on different machines.
1749
1750 More information about the internals of the Linux math coprocessor
1751 emulation can be found in <file:arch/x86/math-emu/README>.
1752
1753 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1754 kernel, it won't hurt.
1755
1756config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001757 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001758 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001759 ---help---
1760 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1761 the Memory Type Range Registers (MTRRs) may be used to control
1762 processor access to memory ranges. This is most useful if you have
1763 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1764 allows bus write transfers to be combined into a larger transfer
1765 before bursting over the PCI/AGP bus. This can increase performance
1766 of image write operations 2.5 times or more. Saying Y here creates a
1767 /proc/mtrr file which may be used to manipulate your processor's
1768 MTRRs. Typically the X server should use this.
1769
1770 This code has a reasonably generic interface so that similar
1771 control registers on other processors can be easily supported
1772 as well:
1773
1774 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1775 Registers (ARRs) which provide a similar functionality to MTRRs. For
1776 these, the ARRs are used to emulate the MTRRs.
1777 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1778 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1779 write-combining. All of these processors are supported by this code
1780 and it makes sense to say Y here if you have one of them.
1781
1782 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1783 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1784 can lead to all sorts of problems, so it's good to say Y here.
1785
1786 You can safely say Y even if your machine doesn't have MTRRs, you'll
1787 just add about 9 KB to your kernel.
1788
Randy Dunlap7225e752008-07-26 17:54:22 -07001789 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001790
Yinghai Lu95ffa242008-04-29 03:52:33 -07001791config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001792 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001793 prompt "MTRR cleanup support"
1794 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001795 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001796 Convert MTRR layout from continuous to discrete, so X drivers can
1797 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001798
Thomas Gleixneraba37282008-07-15 14:48:48 +02001799 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001800 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001801 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001802
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001803 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001804
1805config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001806 int "MTRR cleanup enable value (0-1)"
1807 range 0 1
1808 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001809 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001810 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001811 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001812
Yinghai Lu12031a62008-05-02 02:40:22 -07001813config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1814 int "MTRR cleanup spare reg num (0-7)"
1815 range 0 7
1816 default "1"
1817 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001818 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001819 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001820 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001821
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001822config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001823 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001824 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001825 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001826 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001827 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001828
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001829 PATs are the modern equivalents of MTRRs and are much more
1830 flexible than MTRRs.
1831
1832 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001833 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001834
1835 If unsure, say Y.
1836
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001837config ARCH_USES_PG_UNCACHED
1838 def_bool y
1839 depends on X86_PAT
1840
H. Peter Anvin628c6242011-07-31 13:59:29 -07001841config ARCH_RANDOM
1842 def_bool y
1843 prompt "x86 architectural random number generator" if EXPERT
1844 ---help---
1845 Enable the x86 architectural RDRAND instruction
1846 (Intel Bull Mountain technology) to generate random numbers.
1847 If supported, this is a high bandwidth, cryptographically
1848 secure hardware random number generator.
1849
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001850config X86_SMAP
1851 def_bool y
1852 prompt "Supervisor Mode Access Prevention" if EXPERT
1853 ---help---
1854 Supervisor Mode Access Prevention (SMAP) is a security
1855 feature in newer Intel processors. There is a small
1856 performance cost if this enabled and turned on; there is
1857 also a small increase in the kernel size if this is enabled.
1858
1859 If unsure, say Y.
1860
Ricardo Neriaa35f892017-11-05 18:27:54 -08001861config X86_INTEL_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001862 def_bool y
Ricardo Neriaa35f892017-11-05 18:27:54 -08001863 depends on CPU_SUP_INTEL
1864 prompt "Intel User Mode Instruction Prevention" if EXPERT
1865 ---help---
1866 The User Mode Instruction Prevention (UMIP) is a security
1867 feature in newer Intel processors. If enabled, a general
Ricardo Neri796ebc82017-11-13 22:29:42 -08001868 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1869 or STR instructions are executed in user mode. These instructions
1870 unnecessarily expose information about the hardware state.
1871
1872 The vast majority of applications do not use these instructions.
1873 For the very few that do, software emulation is provided in
1874 specific cases in protected and virtual-8086 modes. Emulated
1875 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001876
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001877config X86_INTEL_MPX
1878 prompt "Intel MPX (Memory Protection Extensions)"
1879 def_bool n
Rik van Rieldf3735c2017-09-06 16:25:11 -07001880 # Note: only available in 64-bit mode due to VMA flags shortage
1881 depends on CPU_SUP_INTEL && X86_64
1882 select ARCH_USES_HIGH_VMA_FLAGS
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001883 ---help---
1884 MPX provides hardware features that can be used in
1885 conjunction with compiler-instrumented code to check
1886 memory references. It is designed to detect buffer
1887 overflow or underflow bugs.
1888
1889 This option enables running applications which are
1890 instrumented or otherwise use MPX. It does not use MPX
1891 itself inside the kernel or to protect the kernel
1892 against bad memory references.
1893
1894 Enabling this option will make the kernel larger:
1895 ~8k of kernel text and 36 bytes of data on a 64-bit
1896 defconfig. It adds a long to the 'mm_struct' which
1897 will increase the kernel memory overhead of each
1898 process and adds some branches to paths used during
1899 exec() and munmap().
1900
1901 For details, see Documentation/x86/intel_mpx.txt
1902
1903 If unsure, say N.
1904
Dave Hansen35e97792016-02-12 13:02:00 -08001905config X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001906 prompt "Intel Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001907 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001908 # Note: only available in 64-bit mode
Dave Hansen35e97792016-02-12 13:02:00 -08001909 depends on CPU_SUP_INTEL && X86_64
Ingo Molnar52c8e602016-11-15 10:15:03 +01001910 select ARCH_USES_HIGH_VMA_FLAGS
1911 select ARCH_HAS_PKEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001912 ---help---
1913 Memory Protection Keys provides a mechanism for enforcing
1914 page-based protections, but without requiring modification of the
1915 page tables when an application changes protection domains.
1916
1917 For details, see Documentation/x86/protection-keys.txt
1918
1919 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001920
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001921config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001922 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001923 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001924 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001925 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001926 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001927 This enables the kernel to use EFI runtime services that are
1928 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001929
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001930 This option is only useful on systems that have EFI firmware.
1931 In addition, you should use the latest ELILO loader available
1932 at <http://elilo.sourceforge.net> in order to take advantage
1933 of EFI runtime services. However, even with this option, the
1934 resultant kernel should continue to boot on existing non-EFI
1935 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001936
Matt Fleming291f3632011-12-12 21:27:52 +00001937config EFI_STUB
1938 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001939 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001940 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001941 ---help---
1942 This kernel feature allows a bzImage to be loaded directly
1943 by EFI firmware without the use of a bootloader.
1944
Roy Franz4172fe22013-09-22 15:45:25 -07001945 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001946
Matt Fleming7d453ee2014-01-10 18:52:06 +00001947config EFI_MIXED
1948 bool "EFI mixed-mode support"
1949 depends on EFI_STUB && X86_64
1950 ---help---
1951 Enabling this feature allows a 64-bit kernel to be booted
1952 on a 32-bit firmware, provided that your CPU supports 64-bit
1953 mode.
1954
1955 Note that it is not possible to boot a mixed-mode enabled
1956 kernel via the EFI boot stub - a bootloader that supports
1957 the EFI handover protocol must be used.
1958
1959 If unsure, say N.
1960
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001961config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001962 def_bool y
1963 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001964 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001965 This kernel feature is useful for number crunching applications
1966 that may need to compute untrusted bytecode during their
1967 execution. By using pipes or other transports made available to
1968 the process as file descriptors supporting the read/write
1969 syscalls, it's possible to isolate those applications in
1970 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001971 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001972 and the task is only allowed to execute a few safe syscalls
1973 defined by each seccomp mode.
1974
1975 If unsure, say Y. Only embedded should say N here.
1976
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001977source kernel/Kconfig.hz
1978
1979config KEXEC
1980 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001981 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001982 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001983 kexec is a system call that implements the ability to shutdown your
1984 current kernel, and to start another kernel. It is like a reboot
1985 but it is independent of the system firmware. And like a reboot
1986 you can start any kernel with it, not just Linux.
1987
1988 The name comes from the similarity to the exec system call.
1989
1990 It is an ongoing process to be certain the hardware in a machine
1991 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001992 initially work for you. As of this writing the exact hardware
1993 interface is strongly in flux, so no good recommendation can be
1994 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001995
Vivek Goyal74ca3172014-08-29 15:18:46 -07001996config KEXEC_FILE
1997 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07001998 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07001999 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07002000 depends on X86_64
2001 depends on CRYPTO=y
2002 depends on CRYPTO_SHA256=y
2003 ---help---
2004 This is new version of kexec system call. This system call is
2005 file based and takes file descriptors as system call argument
2006 for kernel and initramfs as opposed to list of segments as
2007 accepted by previous system call.
2008
AKASHI Takahirob799a092018-04-13 15:35:45 -07002009config ARCH_HAS_KEXEC_PURGATORY
2010 def_bool KEXEC_FILE
2011
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002012config KEXEC_VERIFY_SIG
2013 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07002014 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002015 ---help---
2016 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002017 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002018
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002019 In addition to that option, you need to enable signature
2020 verification for the corresponding kernel image type being
2021 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002022
2023config KEXEC_BZIMAGE_VERIFY_SIG
2024 bool "Enable bzImage signature verification support"
2025 depends on KEXEC_VERIFY_SIG
2026 depends on SIGNED_PE_FILE_VERIFICATION
2027 select SYSTEM_TRUSTED_KEYRING
2028 ---help---
2029 Enable bzImage signature verification support.
2030
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002031config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002032 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002033 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002034 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002035 Generate crash dump after being started by kexec.
2036 This should be normally only set in special crash dump kernels
2037 which are loaded in the main kernel with kexec-tools into
2038 a specially reserved region and then later executed after
2039 a crash by kdump/kexec. The crash dump kernel must be compiled
2040 to a memory address not used by the main kernel or BIOS using
2041 PHYSICAL_START, or it must be built as a relocatable image
2042 (CONFIG_RELOCATABLE=y).
2043 For more details see Documentation/kdump/kdump.txt
2044
Huang Ying3ab83522008-07-25 19:45:07 -07002045config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002046 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002047 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002048 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07002049 Jump between original kernel and kexeced kernel and invoke
2050 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002051
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002052config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002053 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002054 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002055 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002056 This gives the physical address where the kernel is loaded.
2057
2058 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2059 bzImage will decompress itself to above physical address and
2060 run from there. Otherwise, bzImage will run from the address where
2061 it has been loaded by the boot loader and will ignore above physical
2062 address.
2063
2064 In normal kdump cases one does not have to set/change this option
2065 as now bzImage can be compiled as a completely relocatable image
2066 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2067 address. This option is mainly useful for the folks who don't want
2068 to use a bzImage for capturing the crash dump and want to use a
2069 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2070 to be specifically compiled to run from a specific memory area
2071 (normally a reserved region) and this option comes handy.
2072
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002073 So if you are using bzImage for capturing the crash dump,
2074 leave the value here unchanged to 0x1000000 and set
2075 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2076 for capturing the crash dump change this value to start of
2077 the reserved region. In other words, it can be set based on
2078 the "X" value as specified in the "crashkernel=YM@XM"
2079 command line boot parameter passed to the panic-ed
2080 kernel. Please take a look at Documentation/kdump/kdump.txt
2081 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002082
2083 Usage of bzImage for capturing the crash dump is recommended as
2084 one does not have to build two kernels. Same kernel can be used
2085 as production kernel and capture kernel. Above option should have
2086 gone away after relocatable bzImage support is introduced. But it
2087 is present because there are users out there who continue to use
2088 vmlinux for dump capture. This option should go away down the
2089 line.
2090
2091 Don't change this unless you know what you are doing.
2092
2093config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002094 bool "Build a relocatable kernel"
2095 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002096 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002097 This builds a kernel image that retains relocation information
2098 so it can be loaded someplace besides the default 1MB.
2099 The relocations tend to make the kernel binary about 10% larger,
2100 but are discarded at runtime.
2101
2102 One use is for the kexec on panic case where the recovery kernel
2103 must live at a different physical address than the primary
2104 kernel.
2105
2106 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2107 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002108 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002109
Kees Cook8ab38202013-10-10 17:18:14 -07002110config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002111 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002112 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002113 default y
Kees Cook8ab38202013-10-10 17:18:14 -07002114 ---help---
Baoquan Hee8581e32016-04-20 13:55:43 -07002115 In support of Kernel Address Space Layout Randomization (KASLR),
2116 this randomizes the physical address at which the kernel image
2117 is decompressed and the virtual address where the kernel
2118 image is mapped, as a security feature that deters exploit
2119 attempts relying on knowledge of the location of kernel
2120 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002121
Kees Cooked9f0072016-05-25 15:45:33 -07002122 On 64-bit, the kernel physical and virtual addresses are
2123 randomized separately. The physical address will be anywhere
2124 between 16MB and the top of physical memory (up to 64TB). The
2125 virtual address will be randomized from 16MB up to 1GB (9 bits
2126 of entropy). Note that this also reduces the memory space
2127 available to kernel modules from 1.5GB to 1GB.
2128
2129 On 32-bit, the kernel physical and virtual addresses are
2130 randomized together. They will be randomized from 16MB up to
2131 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002132
Baoquan Hee8581e32016-04-20 13:55:43 -07002133 Entropy is generated using the RDRAND instruction if it is
2134 supported. If RDTSC is supported, its value is mixed into
2135 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002136 supported, then entropy is read from the i8254 timer. The
2137 usable entropy is limited by the kernel being built using
2138 2GB addressing, and that PHYSICAL_ALIGN must be at a
2139 minimum of 2MB. As a result, only 10 bits of entropy are
2140 theoretically possible, but the implementations are further
2141 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002142
Ingo Molnar6807c842017-04-18 11:08:12 +02002143 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002144
2145# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002146config X86_NEED_RELOCS
2147 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002148 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002149
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002150config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002151 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002152 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002153 range 0x2000 0x1000000 if X86_32
2154 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002155 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002156 This value puts the alignment restrictions on physical address
2157 where kernel is loaded and run from. Kernel is compiled for an
2158 address which meets above alignment restriction.
2159
2160 If bootloader loads the kernel at a non-aligned address and
2161 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2162 address aligned to above value and run from there.
2163
2164 If bootloader loads the kernel at a non-aligned address and
2165 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2166 load address and decompress itself to the address it has been
2167 compiled for and run from there. The address for which kernel is
2168 compiled already meets above alignment restrictions. Hence the
2169 end result is that kernel runs from a physical address meeting
2170 above alignment restrictions.
2171
Kees Cooka0215062013-07-08 09:15:17 -07002172 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2173 this value must be a multiple of 0x200000.
2174
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002175 Don't change this unless you know what you are doing.
2176
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002177config DYNAMIC_MEMORY_LAYOUT
2178 bool
2179 ---help---
2180 This option makes base addresses of vmalloc and vmemmap as well as
2181 __PAGE_OFFSET movable during boot.
2182
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002183config RANDOMIZE_MEMORY
2184 bool "Randomize the kernel memory sections"
2185 depends on X86_64
2186 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002187 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002188 default RANDOMIZE_BASE
2189 ---help---
2190 Randomizes the base virtual address of kernel memory sections
2191 (physical memory mapping, vmalloc & vmemmap). This security feature
2192 makes exploits relying on predictable memory locations less reliable.
2193
2194 The order of allocations remains unchanged. Entropy is generated in
2195 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2196 configuration have in average 30,000 different possible virtual
2197 addresses for each memory section.
2198
Ingo Molnar6807c842017-04-18 11:08:12 +02002199 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002200
Thomas Garnier90397a42016-06-21 17:47:06 -07002201config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2202 hex "Physical memory mapping padding" if EXPERT
2203 depends on RANDOMIZE_MEMORY
2204 default "0xa" if MEMORY_HOTPLUG
2205 default "0x0"
2206 range 0x1 0x40 if MEMORY_HOTPLUG
2207 range 0x0 0x40
2208 ---help---
2209 Define the padding in terabytes added to the existing physical
2210 memory size during kernel memory randomization. It is useful
2211 for memory hotplug support but reduces the entropy available for
2212 address randomization.
2213
2214 If unsure, leave at the default value.
2215
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002216config HOTPLUG_CPU
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002217 bool "Support for hot-pluggable CPUs"
Stephen Rothwell40b31362013-05-21 13:49:35 +10002218 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002219 ---help---
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002220 Say Y here to allow turning CPUs off and on. CPUs can be
2221 controlled through /sys/devices/system/cpu.
2222 ( Note: power management support will enable this option
2223 automatically on SMP systems. )
2224 Say N if you want to disable CPU hotplug.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002225
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002226config BOOTPARAM_HOTPLUG_CPU0
2227 bool "Set default setting of cpu0_hotpluggable"
2228 default n
Kees Cook2c922cd2013-01-22 13:01:19 -08002229 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002230 ---help---
2231 Set whether default state of cpu0_hotpluggable is on or off.
2232
2233 Say Y here to enable CPU0 hotplug by default. If this switch
2234 is turned on, there is no need to give cpu0_hotplug kernel
2235 parameter and the CPU0 hotplug feature is enabled by default.
2236
2237 Please note: there are two known CPU0 dependencies if you want
2238 to enable the CPU0 hotplug feature either by this switch or by
2239 cpu0_hotplug kernel parameter.
2240
2241 First, resume from hibernate or suspend always starts from CPU0.
2242 So hibernate and suspend are prevented if CPU0 is offline.
2243
2244 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2245 offline if any interrupt can not migrate out of CPU0. There may
2246 be other CPU0 dependencies.
2247
2248 Please make sure the dependencies are under your control before
2249 you enable this feature.
2250
2251 Say N if you don't want to enable CPU0 hotplug feature by default.
2252 You still can enable the CPU0 hotplug feature at boot by kernel
2253 parameter cpu0_hotplug.
2254
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002255config DEBUG_HOTPLUG_CPU0
2256 def_bool n
2257 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002258 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002259 ---help---
2260 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2261 soon as possible and boots up userspace with CPU0 offlined. User
2262 can online CPU0 back after boot time.
2263
2264 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2265 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2266 compilation or giving cpu0_hotplug kernel parameter at boot.
2267
2268 If unsure, say N.
2269
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002270config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002271 def_bool n
2272 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002273 depends on COMPAT_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002274 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002275 Certain buggy versions of glibc will crash if they are
2276 presented with a 32-bit vDSO that is not mapped at the address
2277 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002278
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002279 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2280 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2281 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2282 the only released version with the bug, but OpenSUSE 9
2283 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002284
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002285 The symptom of the bug is that everything crashes on startup, saying:
2286 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2287
2288 Saying Y here changes the default value of the vdso32 boot
2289 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2290 This works around the glibc bug but hurts performance.
2291
2292 If unsure, say N: if you are compiling your own kernel, you
2293 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002294
Kees Cook3dc33bd2015-08-12 17:55:19 -07002295choice
2296 prompt "vsyscall table for legacy applications"
2297 depends on X86_64
2298 default LEGACY_VSYSCALL_EMULATE
2299 help
2300 Legacy user code that does not know how to find the vDSO expects
2301 to be able to issue three syscalls by calling fixed addresses in
2302 kernel space. Since this location is not randomized with ASLR,
2303 it can be used to assist security vulnerability exploitation.
2304
2305 This setting can be changed at boot time via the kernel command
Andy Lutomirski076ca272018-03-07 11:12:27 -08002306 line parameter vsyscall=[emulate|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002307
2308 On a system with recent enough glibc (2.14 or newer) and no
2309 static binaries, you can say None without a performance penalty
2310 to improve security.
2311
2312 If unsure, select "Emulate".
2313
Kees Cook3dc33bd2015-08-12 17:55:19 -07002314 config LEGACY_VSYSCALL_EMULATE
2315 bool "Emulate"
2316 help
2317 The kernel traps and emulates calls into the fixed
2318 vsyscall address mapping. This makes the mapping
2319 non-executable, but it still contains known contents,
2320 which could be used in certain rare security vulnerability
2321 exploits. This configuration is recommended when userspace
2322 still uses the vsyscall area.
2323
2324 config LEGACY_VSYSCALL_NONE
2325 bool "None"
2326 help
2327 There will be no vsyscall mapping at all. This will
2328 eliminate any risk of ASLR bypass due to the vsyscall
2329 fixed address mapping. Attempts to use the vsyscalls
2330 will be reported to dmesg, so that either old or
2331 malicious userspace programs can be identified.
2332
2333endchoice
2334
Tim Bird516cbf32008-08-12 12:52:36 -07002335config CMDLINE_BOOL
2336 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002337 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002338 Allow for specifying boot arguments to the kernel at
2339 build time. On some systems (e.g. embedded ones), it is
2340 necessary or convenient to provide some or all of the
2341 kernel boot arguments with the kernel itself (that is,
2342 to not rely on the boot loader to provide them.)
2343
2344 To compile command line arguments into the kernel,
2345 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002346 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002347
2348 Systems with fully functional boot loaders (i.e. non-embedded)
2349 should leave this option set to 'N'.
2350
2351config CMDLINE
2352 string "Built-in kernel command string"
2353 depends on CMDLINE_BOOL
2354 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002355 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002356 Enter arguments here that should be compiled into the kernel
2357 image and used at boot time. If the boot loader provides a
2358 command line at boot time, it is appended to this string to
2359 form the full kernel command line, when the system boots.
2360
2361 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2362 change this behavior.
2363
2364 In most cases, the command line (whether built-in or provided
2365 by the boot loader) should specify the device for the root
2366 file system.
2367
2368config CMDLINE_OVERRIDE
2369 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002370 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002371 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002372 Set this option to 'Y' to have the kernel ignore the boot loader
2373 command line, and use ONLY the built-in command line.
2374
2375 This is used to work around broken boot loaders. This should
2376 be set to 'N' under normal conditions.
2377
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002378config MODIFY_LDT_SYSCALL
2379 bool "Enable the LDT (local descriptor table)" if EXPERT
2380 default y
2381 ---help---
2382 Linux can allow user programs to install a per-process x86
2383 Local Descriptor Table (LDT) using the modify_ldt(2) system
2384 call. This is required to run 16-bit or segmented code such as
2385 DOSEMU or some Wine programs. It is also used by some very old
2386 threading libraries.
2387
2388 Enabling this feature adds a small amount of overhead to
2389 context switches and increases the low-level kernel attack
2390 surface. Disabling it removes the modify_ldt(2) system call.
2391
2392 Saying 'N' here may make sense for embedded or server kernels.
2393
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002394source "kernel/livepatch/Kconfig"
2395
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002396endmenu
2397
Michal Hocko3072e412017-09-08 16:11:39 -07002398config ARCH_HAS_ADD_PAGES
2399 def_bool y
2400 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2401
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002402config ARCH_ENABLE_MEMORY_HOTPLUG
2403 def_bool y
2404 depends on X86_64 || (X86_32 && HIGHMEM)
2405
Gary Hade35551052008-10-31 10:52:03 -07002406config ARCH_ENABLE_MEMORY_HOTREMOVE
2407 def_bool y
2408 depends on MEMORY_HOTPLUG
2409
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002410config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002411 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002412 depends on NUMA
2413
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002414config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2415 def_bool y
2416 depends on X86_64 || X86_PAE
2417
Naoya Horiguchic177c812014-06-04 16:05:35 -07002418config ARCH_ENABLE_HUGEPAGE_MIGRATION
2419 def_bool y
2420 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2421
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002422config ARCH_ENABLE_THP_MIGRATION
2423 def_bool y
2424 depends on X86_64 && TRANSPARENT_HUGEPAGE
2425
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002426menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002427
2428config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002429 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002430 depends on X86_64 && HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002431
2432source "kernel/power/Kconfig"
2433
2434source "drivers/acpi/Kconfig"
2435
Feng Tangefafc8b2009-08-14 15:23:29 -04002436source "drivers/sfi/Kconfig"
2437
Andi Kleena6b68072008-01-30 13:32:49 +01002438config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002439 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002440 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002441
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002442menuconfig APM
2443 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002444 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002445 ---help---
2446 APM is a BIOS specification for saving power using several different
2447 techniques. This is mostly useful for battery powered laptops with
2448 APM compliant BIOSes. If you say Y here, the system time will be
2449 reset after a RESUME operation, the /proc/apm device will provide
2450 battery status information, and user-space programs will receive
2451 notification of APM "events" (e.g. battery status change).
2452
2453 If you select "Y" here, you can disable actual use of the APM
2454 BIOS by passing the "apm=off" option to the kernel at boot time.
2455
2456 Note that the APM support is almost completely disabled for
2457 machines with more than one CPU.
2458
2459 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002460 and more information, read <file:Documentation/power/apm-acpi.txt>
2461 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002462 <http://www.tldp.org/docs.html#howto>.
2463
2464 This driver does not spin down disk drives (see the hdparm(8)
2465 manpage ("man 8 hdparm") for that), and it doesn't turn off
2466 VESA-compliant "green" monitors.
2467
2468 This driver does not support the TI 4000M TravelMate and the ACER
2469 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2470 desktop machines also don't have compliant BIOSes, and this driver
2471 may cause those machines to panic during the boot phase.
2472
2473 Generally, if you don't have a battery in your machine, there isn't
2474 much point in using this driver and you should say N. If you get
2475 random kernel OOPSes or reboots that don't seem to be related to
2476 anything, try disabling/enabling this option (or disabling/enabling
2477 APM in your BIOS).
2478
2479 Some other things you should try when experiencing seemingly random,
2480 "weird" problems:
2481
2482 1) make sure that you have enough swap space and that it is
2483 enabled.
2484 2) pass the "no-hlt" option to the kernel
2485 3) switch on floating point emulation in the kernel and pass
2486 the "no387" option to the kernel
2487 4) pass the "floppy=nodma" option to the kernel
2488 5) pass the "mem=4M" option to the kernel (thereby disabling
2489 all but the first 4 MB of RAM)
2490 6) make sure that the CPU is not over clocked.
2491 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2492 8) disable the cache from your BIOS settings
2493 9) install a fan for the video card or exchange video RAM
2494 10) install a better fan for the CPU
2495 11) exchange RAM chips
2496 12) exchange the motherboard.
2497
2498 To compile this driver as a module, choose M here: the
2499 module will be called apm.
2500
2501if APM
2502
2503config APM_IGNORE_USER_SUSPEND
2504 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002505 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002506 This option will ignore USER SUSPEND requests. On machines with a
2507 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2508 series notebooks, it is necessary to say Y because of a BIOS bug.
2509
2510config APM_DO_ENABLE
2511 bool "Enable PM at boot time"
2512 ---help---
2513 Enable APM features at boot time. From page 36 of the APM BIOS
2514 specification: "When disabled, the APM BIOS does not automatically
2515 power manage devices, enter the Standby State, enter the Suspend
2516 State, or take power saving steps in response to CPU Idle calls."
2517 This driver will make CPU Idle calls when Linux is idle (unless this
2518 feature is turned off -- see "Do CPU IDLE calls", below). This
2519 should always save battery power, but more complicated APM features
2520 will be dependent on your BIOS implementation. You may need to turn
2521 this option off if your computer hangs at boot time when using APM
2522 support, or if it beeps continuously instead of suspending. Turn
2523 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2524 T400CDT. This is off by default since most machines do fine without
2525 this feature.
2526
2527config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002528 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002529 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002530 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002531 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2532 On some machines, this can activate improved power savings, such as
2533 a slowed CPU clock rate, when the machine is idle. These idle calls
2534 are made after the idle loop has run for some length of time (e.g.,
2535 333 mS). On some machines, this will cause a hang at boot time or
2536 whenever the CPU becomes idle. (On machines with more than one CPU,
2537 this option does nothing.)
2538
2539config APM_DISPLAY_BLANK
2540 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002541 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002542 Enable console blanking using the APM. Some laptops can use this to
2543 turn off the LCD backlight when the screen blanker of the Linux
2544 virtual console blanks the screen. Note that this is only used by
2545 the virtual console screen blanker, and won't turn off the backlight
2546 when using the X Window system. This also doesn't have anything to
2547 do with your VESA-compliant power-saving monitor. Further, this
2548 option doesn't work for all laptops -- it might not turn off your
2549 backlight at all, or it might print a lot of errors to the console,
2550 especially if you are using gpm.
2551
2552config APM_ALLOW_INTS
2553 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002554 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002555 Normally we disable external interrupts while we are making calls to
2556 the APM BIOS as a measure to lessen the effects of a badly behaving
2557 BIOS implementation. The BIOS should reenable interrupts if it
2558 needs to. Unfortunately, some BIOSes do not -- especially those in
2559 many of the newer IBM Thinkpads. If you experience hangs when you
2560 suspend, try setting this to Y. Otherwise, say N.
2561
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002562endif # APM
2563
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002564source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002565
2566source "drivers/cpuidle/Kconfig"
2567
Andy Henroid27471fd2008-10-09 11:45:22 -07002568source "drivers/idle/Kconfig"
2569
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002570endmenu
2571
2572
2573menu "Bus options (PCI etc.)"
2574
2575config PCI
Ingo Molnar1ac97012008-05-19 14:10:14 +02002576 bool "PCI support"
Adrian Bunk1c858082008-01-30 13:32:32 +01002577 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002578 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002579 Find out whether you have a PCI motherboard. PCI is the name of a
2580 bus system, i.e. the way the CPU talks to the other stuff inside
2581 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2582 VESA. If you have PCI, say Y, otherwise N.
2583
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002584choice
2585 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002586 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002587 default PCI_GOANY
2588 ---help---
2589 On PCI systems, the BIOS can be used to detect the PCI devices and
2590 determine their configuration. However, some old PCI motherboards
2591 have BIOS bugs and may crash if this is done. Also, some embedded
2592 PCI-based systems don't have any BIOS at all. Linux can also try to
2593 detect the PCI hardware directly without using the BIOS.
2594
2595 With this option, you can specify how Linux should detect the
2596 PCI devices. If you choose "BIOS", the BIOS will be used,
2597 if you choose "Direct", the BIOS won't be used, and if you
2598 choose "MMConfig", then PCI Express MMCONFIG will be used.
2599 If you choose "Any", the kernel will try MMCONFIG, then the
2600 direct access method and falls back to the BIOS if that doesn't
2601 work. If unsure, go with the default, which is "Any".
2602
2603config PCI_GOBIOS
2604 bool "BIOS"
2605
2606config PCI_GOMMCONFIG
2607 bool "MMConfig"
2608
2609config PCI_GODIRECT
2610 bool "Direct"
2611
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002612config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002613 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002614 depends on OLPC
2615
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002616config PCI_GOANY
2617 bool "Any"
2618
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002619endchoice
2620
2621config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002622 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002623 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002624
2625# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2626config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002627 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002628 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002629
2630config PCI_MMCONFIG
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002631 bool "Support mmconfig PCI config space access" if X86_64
2632 default y
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002633 depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002634 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002635
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002636config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002637 def_bool y
2638 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002639
Alex Nixonb5401a92010-03-18 16:31:34 -04002640config PCI_XEN
2641 def_bool y
2642 depends on PCI && XEN
2643 select SWIOTLB_XEN
2644
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002645config PCI_DOMAINS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002646 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002647 depends on PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002648
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002649config MMCONF_FAM10H
2650 def_bool y
2651 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002652
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002653config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002654 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002655 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002656 help
2657 Read the PCI windows out of the CNB20LE host bridge. This allows
2658 PCI hotplug to work on systems with the CNB20LE chipset which do
2659 not have ACPI.
2660
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002661 There's no public spec for this chipset, and this functionality
2662 is known to be incomplete.
2663
2664 You should say N unless you know you need this.
2665
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002666source "drivers/pci/Kconfig"
2667
William Breathitt Gray3a495512016-05-27 18:08:27 -04002668config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002669 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002670 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002671 Expose ISA bus device drivers and options available for selection and
2672 configuration. Enable this option if your target machine has an ISA
2673 bus. ISA is an older system, displaced by PCI and newer bus
2674 architectures -- if your target machine is modern, it probably does
2675 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002676
2677 If unsure, say N.
2678
David Rientjes1c00f012011-03-22 16:34:59 -07002679# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002680config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002681 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2682 default y
2683 help
2684 Enables ISA-style DMA support for devices requiring such controllers.
2685 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002686
Linus Torvalds51e68d02016-05-21 10:25:19 -07002687if X86_32
2688
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002689config ISA
2690 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002691 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002692 Find out whether you have ISA slots on your motherboard. ISA is the
2693 name of a bus system, i.e. the way the CPU talks to the other stuff
2694 inside your box. Other bus systems are PCI, EISA, MicroChannel
2695 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2696 newer boards don't support it. If you have ISA, say Y, otherwise N.
2697
2698config EISA
2699 bool "EISA support"
2700 depends on ISA
2701 ---help---
2702 The Extended Industry Standard Architecture (EISA) bus was
2703 developed as an open alternative to the IBM MicroChannel bus.
2704
2705 The EISA bus provided some of the features of the IBM MicroChannel
2706 bus while maintaining backward compatibility with cards made for
2707 the older ISA bus. The EISA bus saw limited use between 1988 and
2708 1995 when it was made obsolete by the PCI bus.
2709
2710 Say Y here if you are building a kernel for an EISA-based machine.
2711
2712 Otherwise, say N.
2713
2714source "drivers/eisa/Kconfig"
2715
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002716config SCx200
2717 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002718 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002719 This provides basic support for National Semiconductor's
2720 (now AMD's) Geode processors. The driver probes for the
2721 PCI-IDs of several on-chip devices, so its a good dependency
2722 for other scx200_* drivers.
2723
2724 If compiled as a module, the driver is named scx200.
2725
2726config SCx200HR_TIMER
2727 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002728 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002729 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002730 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002731 This driver provides a clocksource built upon the on-chip
2732 27MHz high-resolution timer. Its also a workaround for
2733 NSC Geode SC-1100's buggy TSC, which loses time when the
2734 processor goes idle (as is done by the scheduler). The
2735 other workaround is idle=poll boot option.
2736
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002737config OLPC
2738 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002739 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002740 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002741 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002742 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002743 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002744 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002745 Add support for detecting the unique features of the OLPC
2746 XO hardware.
2747
Daniel Drakea3128582011-06-25 17:34:10 +01002748config OLPC_XO1_PM
2749 bool "OLPC XO-1 Power Management"
Daniel Drake97c4cb72011-06-25 17:34:11 +01002750 depends on OLPC && MFD_CS5535 && PM_SLEEP
Daniel Drakea3128582011-06-25 17:34:10 +01002751 select MFD_CORE
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002752 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002753 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002754
Daniel Drakecfee9592011-06-25 17:34:17 +01002755config OLPC_XO1_RTC
2756 bool "OLPC XO-1 Real Time Clock"
2757 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2758 ---help---
2759 Add support for the XO-1 real time clock, which can be used as a
2760 programmable wakeup source.
2761
Daniel Drake7feda8e2011-06-25 17:34:12 +01002762config OLPC_XO1_SCI
2763 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002764 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002765 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002766 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002767 ---help---
2768 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002769 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002770 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002771 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002772 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002773 - AC adapter status updates
2774 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002775
Daniel Drakea0f30f52011-06-25 17:34:18 +01002776config OLPC_XO15_SCI
2777 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002778 depends on OLPC && ACPI
2779 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002780 ---help---
2781 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2782 - EC-driven system wakeups
2783 - AC adapter status updates
2784 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002785
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002786config ALIX
2787 bool "PCEngines ALIX System Support (LED setup)"
2788 select GPIOLIB
2789 ---help---
2790 This option enables system support for the PCEngines ALIX.
2791 At present this just sets up LEDs for GPIO control on
2792 ALIX2/3/6 boards. However, other system specific setup should
2793 get added here.
2794
2795 Note: You must still enable the drivers for GPIO and LED support
2796 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2797
2798 Note: You have to set alix.force=1 for boards with Award BIOS.
2799
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002800config NET5501
2801 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2802 select GPIOLIB
2803 ---help---
2804 This option enables system support for the Soekris Engineering net5501.
2805
Philip A. Prindeville31970592012-01-14 01:45:39 -07002806config GEOS
2807 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2808 select GPIOLIB
2809 depends on DMI
2810 ---help---
2811 This option enables system support for the Traverse Technologies GEOS.
2812
Vivien Didelot7d029122013-01-04 16:18:14 -05002813config TS5500
2814 bool "Technologic Systems TS-5500 platform support"
2815 depends on MELAN
2816 select CHECK_SIGNATURE
2817 select NEW_LEDS
2818 select LEDS_CLASS
2819 ---help---
2820 This option enables system support for the Technologic Systems TS-5500.
2821
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002822endif # X86_32
2823
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002824config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002825 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002826 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002827
2828source "drivers/pcmcia/Kconfig"
2829
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002830config RAPIDIO
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002831 tristate "RapidIO support"
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002832 depends on PCI
2833 default n
2834 help
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002835 If enabled this option will include drivers and the core
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002836 infrastructure code to support RapidIO interconnect devices.
2837
2838source "drivers/rapidio/Kconfig"
2839
David Herrmanne3263ab2013-08-02 14:05:22 +02002840config X86_SYSFB
2841 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2842 help
2843 Firmwares often provide initial graphics framebuffers so the BIOS,
2844 bootloader or kernel can show basic video-output during boot for
2845 user-guidance and debugging. Historically, x86 used the VESA BIOS
2846 Extensions and EFI-framebuffers for this, which are mostly limited
2847 to x86.
2848 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2849 framebuffers so the new generic system-framebuffer drivers can be
2850 used on x86. If the framebuffer is not compatible with the generic
2851 modes, it is adverticed as fallback platform framebuffer so legacy
2852 drivers like efifb, vesafb and uvesafb can pick it up.
2853 If this option is not selected, all system framebuffers are always
2854 marked as fallback platform framebuffers as usual.
2855
2856 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2857 not be able to pick up generic system framebuffers if this option
2858 is selected. You are highly encouraged to enable simplefb as
2859 replacement if you select this option. simplefb can correctly deal
2860 with generic system framebuffers. But you should still keep vesafb
2861 and others enabled as fallback if a system framebuffer is
2862 incompatible with simplefb.
2863
2864 If unsure, say Y.
2865
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002866endmenu
2867
2868
2869menu "Executable file formats / Emulations"
2870
2871source "fs/Kconfig.binfmt"
2872
2873config IA32_EMULATION
2874 bool "IA32 Emulation"
2875 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002876 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002877 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002878 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002879 select COMPAT_OLD_SIGACTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002880 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002881 Include code to run legacy 32-bit programs under a
2882 64-bit kernel. You should likely turn this on, unless you're
2883 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002884
2885config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002886 tristate "IA32 a.out support"
2887 depends on IA32_EMULATION
2888 ---help---
2889 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002890
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002891config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002892 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002893 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002894 ---help---
2895 Include code to run binaries for the x32 native 32-bit ABI
2896 for 64-bit processors. An x32 process gets access to the
2897 full 64-bit register file and wide data path while leaving
2898 pointers at 32 bits for smaller memory footprint.
2899
2900 You will need a recent binutils (2.22 or later) with
2901 elf32_x86_64 support enabled to compile a kernel with this
2902 option set.
2903
Ingo Molnar953fee12016-11-15 10:22:52 +01002904config COMPAT_32
2905 def_bool y
2906 depends on IA32_EMULATION || X86_32
2907 select HAVE_UID16
2908 select OLD_SIGSUSPEND3
2909
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002910config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002911 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002912 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002913
Jan Beulich3120e252012-09-10 12:41:45 +01002914if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002915config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002916 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002917
2918config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002919 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002920 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002921endif
David Howellsee009e4a02011-03-07 15:06:20 +00002922
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002923endmenu
2924
2925
Keith Packarde5beae12008-11-03 18:21:45 +01002926config HAVE_ATOMIC_IOMAP
2927 def_bool y
2928 depends on X86_32
2929
Alessandro Rubini4692d772012-04-04 19:39:58 +02002930config X86_DEV_DMA_OPS
2931 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002932 depends on X86_64 || STA2X11
Alessandro Rubini4692d772012-04-04 19:39:58 +02002933
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002934config X86_DMA_REMAP
2935 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002936 depends on STA2X11
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002937
Kirill A. Shutemove5855132017-06-06 14:31:20 +03002938config HAVE_GENERIC_GUP
2939 def_bool y
2940
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002941source "net/Kconfig"
2942
2943source "drivers/Kconfig"
2944
2945source "drivers/firmware/Kconfig"
2946
2947source "fs/Kconfig"
2948
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002949source "arch/x86/Kconfig.debug"
2950
2951source "security/Kconfig"
2952
2953source "crypto/Kconfig"
2954
Avi Kivityedf88412007-12-16 11:02:48 +02002955source "arch/x86/kvm/Kconfig"
2956
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002957source "lib/Kconfig"