blob: 1fe24b624d44c9cc1611c18fea8ab87ed070d147 [file] [log] [blame]
Greg Kroah-Hartmanb2441312017-11-01 15:07:57 +01001# SPDX-License-Identifier: GPL-2.0
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01002# Select 32 or 64 bit
3config 64BIT
Sam Ravnborg68409992007-11-17 15:37:31 +01004 bool "64-bit kernel" if ARCH = "x86"
David Woodhouseffee0de2012-12-20 21:51:55 +00005 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
Kees Cook39208aa2017-09-02 13:09:46 -070063 select ARCH_HAS_REFCOUNT
Dan Williams0aed55a2017-05-29 12:22:50 -070064 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Dan Williams87803562018-05-03 17:06:31 -070065 select ARCH_HAS_UACCESS_MCSAFE if X86_64
Daniel Borkmannd2852a22017-02-21 16:09:33 +010066 select ARCH_HAS_SET_MEMORY
Ingo Molnar6471b822015-06-03 10:00:13 +020067 select ARCH_HAS_SG_CHAIN
Laura Abbottad21fc42017-02-06 16:31:57 -080068 select ARCH_HAS_STRICT_KERNEL_RWX
69 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050070 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Andrey Ryabininc6d30852016-01-20 15:00:55 -080071 select ARCH_HAS_UBSAN_SANITIZE_ALL
Oliver O'Halloran65f7d042017-06-28 11:32:31 +100072 select ARCH_HAS_ZONE_DEVICE if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020073 select ARCH_HAVE_NMI_SAFE_CMPXCHG
74 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040075 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080076 select ARCH_MIGHT_HAVE_PC_SERIO
Ingo Molnar6471b822015-06-03 10:00:13 +020077 select ARCH_SUPPORTS_ATOMIC_RMW
Ingo Molnar6471b822015-06-03 10:00:13 +020078 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
79 select ARCH_USE_BUILTIN_BSWAP
Ingo Molnar6471b822015-06-03 10:00:13 +020080 select ARCH_USE_QUEUED_RWLOCKS
81 select ARCH_USE_QUEUED_SPINLOCKS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -070082 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Ingo Molnarc763ea22016-11-15 10:26:39 +010083 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Huang Ying38d8b4e2017-07-06 15:37:18 -070084 select ARCH_WANTS_THP_SWAP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020085 select BUILDTIME_EXTABLE_SORT
86 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +020087 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
88 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +020089 select DCACHE_WORD_ACCESS
Christoph Hellwigfec777c2018-03-19 11:38:15 +010090 select DMA_DIRECT_OPS
Linus Torvalds45471cd2015-06-24 19:52:06 -070091 select EDAC_ATOMIC_SCRUB
92 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +020093 select GENERIC_CLOCKEVENTS
94 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
95 select GENERIC_CLOCKEVENTS_MIN_ADJUST
96 select GENERIC_CMOS_UPDATE
97 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +010098 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +020099 select GENERIC_EARLY_IOREMAP
100 select GENERIC_FIND_FIRST_BIT
101 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +0200102 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +0200103 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +0200104 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200105 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200106 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200107 select GENERIC_IRQ_SHOW
108 select GENERIC_PENDING_IRQ if SMP
109 select GENERIC_SMP_IDLE_THREAD
110 select GENERIC_STRNCPY_FROM_USER
111 select GENERIC_STRNLEN_USER
112 select GENERIC_TIME_VSYSCALL
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200113 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200114 select HAVE_ACPI_APEI if ACPI
115 select HAVE_ACPI_APEI_NMI if ACPI
116 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200117 select HAVE_ARCH_AUDITSYSCALL
118 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
119 select HAVE_ARCH_JUMP_LABEL
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800120 select HAVE_ARCH_KASAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200121 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800122 select HAVE_ARCH_MMAP_RND_BITS if MMU
123 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300124 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ingo Molnar6471b822015-06-03 10:00:13 +0200125 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700126 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Ingo Molnar6471b822015-06-03 10:00:13 +0200127 select HAVE_ARCH_TRACEHOOK
128 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Matthew Wilcoxa00cc7d2017-02-24 14:57:02 -0800129 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
Andy Lutomirskie37e43a2016-08-11 02:35:23 -0700130 select HAVE_ARCH_VMAP_STACK if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100131 select HAVE_ARCH_WITHIN_STACK_FRAMES
Ingo Molnar6471b822015-06-03 10:00:13 +0200132 select HAVE_CC_STACKPROTECTOR
133 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
Ingo Molnarc763ea22016-11-15 10:26:39 +0100143 select HAVE_EBPF_JIT if X86_64
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
Ingo Molnarc763ea22016-11-15 10:26:39 +0100184 select HAVE_STACK_VALIDATION if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200185 select HAVE_SYSCALL_TRACEPOINTS
Ingo Molnar6471b822015-06-03 10:00:13 +0200186 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300187 select HAVE_USER_RETURN_NOTIFIER
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100188 select IRQ_FORCED_THREADING
Christoph Hellwig86596f02018-04-05 09:44:52 +0200189 select NEED_SG_DMA_LENGTH
Thomas Gleixnerdf65c1b2017-03-16 22:50:07 +0100190 select PCI_LOCKLESS_CONFIG
Ingo Molnar6471b822015-06-03 10:00:13 +0200191 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500192 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200193 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200194 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500195 select SRCU
Ingo Molnar6471b822015-06-03 10:00:13 +0200196 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700197 select THREAD_INFO_IN_TASK
Ingo Molnar6471b822015-06-03 10:00:13 +0200198 select USER_STACKTRACE_SUPPORT
199 select VIRT_TO_BUS
Ingo Molnar6471b822015-06-03 10:00:13 +0200200 select X86_FEATURE_NAMES if PROC_FS
Balbir Singh7d8330a2008-02-10 12:46:28 +0530201
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200202config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100203 def_bool y
204 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200205
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700206config OUTPUT_FORMAT
207 string
208 default "elf32-i386" if X86_32
209 default "elf64-x86-64" if X86_64
210
Sam Ravnborg73531902008-05-25 23:03:18 +0200211config ARCH_DEFCONFIG
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200212 string
Sam Ravnborg73531902008-05-25 23:03:18 +0200213 default "arch/x86/configs/i386_defconfig" if X86_32
214 default "arch/x86/configs/x86_64_defconfig" if X86_64
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200215
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100216config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100217 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100218
219config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100220 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100221
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100222config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100223 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100224
Daniel Cashman9e08f572016-01-14 15:20:06 -0800225config ARCH_MMAP_RND_BITS_MIN
226 default 28 if 64BIT
227 default 8
228
229config ARCH_MMAP_RND_BITS_MAX
230 default 32 if 64BIT
231 default 16
232
233config ARCH_MMAP_RND_COMPAT_BITS_MIN
234 default 8
235
236config ARCH_MMAP_RND_COMPAT_BITS_MAX
237 default 16
238
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100239config SBUS
240 bool
241
242config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100243 def_bool y
244 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100245
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100246config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100247 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100248 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000249 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
250
251config GENERIC_BUG_RELATIVE_POINTERS
252 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100253
254config GENERIC_HWEIGHT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100255 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100256
257config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100258 def_bool y
259 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100260
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100261config RWSEM_XCHGADD_ALGORITHM
Jan Beulich3120e252012-09-10 12:41:45 +0100262 def_bool y
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100263
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100264config GENERIC_CALIBRATE_DELAY
265 def_bool y
266
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800267config ARCH_HAS_CPU_RELAX
268 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100269
Pekka Enberg1b27d052008-04-28 02:12:22 -0700270config ARCH_HAS_CACHE_LINE_SIZE
271 def_bool y
272
Dave Hansen316d0972018-04-20 15:20:28 -0700273config ARCH_HAS_FILTER_PGPROT
274 def_bool y
275
Mike Travisdd5af902008-01-30 13:33:32 +0100276config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900277 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100278
Tejun Heo08fc4582009-08-14 15:00:49 +0900279config NEED_PER_CPU_EMBED_FIRST_CHUNK
280 def_bool y
281
282config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900283 def_bool y
284
Johannes Berg801e4062007-12-08 02:12:39 +0100285config ARCH_HIBERNATION_POSSIBLE
286 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100287
Johannes Bergf4cb5702007-12-08 02:14:00 +0100288config ARCH_SUSPEND_POSSIBLE
289 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100290
Steve Cappercfe28c52013-04-29 14:29:48 +0100291config ARCH_WANT_HUGE_PMD_SHARE
292 def_bool y
293
Steve Capper53313b22013-04-30 08:03:42 +0100294config ARCH_WANT_GENERAL_HUGETLB
295 def_bool y
296
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100297config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000298 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100299
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100300config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000301 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100302
Ingo Molnar765c68b2008-04-09 11:03:37 +0200303config ARCH_SUPPORTS_OPTIMIZED_INLINING
304 def_bool y
305
Akinobu Mita6a11f752009-03-31 15:23:17 -0700306config ARCH_SUPPORTS_DEBUG_PAGEALLOC
307 def_bool y
308
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300309config KASAN_SHADOW_OFFSET
310 hex
311 depends on KASAN
312 default 0xdffffc0000000000
313
Shane Wang69575d32009-09-01 18:25:07 -0700314config HAVE_INTEL_TXT
315 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700316 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700317
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100318config X86_32_SMP
319 def_bool y
320 depends on X86_32 && SMP
321
322config X86_64_SMP
323 def_bool y
324 depends on X86_64 && SMP
325
Tejun Heoccbeed32009-02-09 22:17:40 +0900326config X86_32_LAZY_GS
327 def_bool y
Kees Cook2bc2f682018-02-06 15:37:41 -0800328 depends on X86_32 && CC_STACKPROTECTOR_NONE
Tejun Heoccbeed32009-02-09 22:17:40 +0900329
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530330config ARCH_SUPPORTS_UPROBES
331 def_bool y
332
Rob Herringd20642f2014-04-18 17:19:54 -0500333config FIX_EARLYCON_MEM
334 def_bool y
335
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700336config PGTABLE_LEVELS
337 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300338 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700339 default 4 if X86_64
340 default 3 if X86_PAE
341 default 2
342
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100343source "init/Kconfig"
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700344source "kernel/Kconfig.freezer"
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100345
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100346menu "Processor type and features"
347
Randy Dunlap5ee71532012-01-16 11:57:18 -0800348config ZONE_DMA
349 bool "DMA memory allocation support" if EXPERT
350 default y
351 help
352 DMA memory allocation support allows devices with less than 32-bit
353 addressing to allocate within the first 16MB of address space.
354 Disable if no such devices will be used.
355
356 If unsure, say Y.
357
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100358config SMP
359 bool "Symmetric multi-processing support"
360 ---help---
361 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800362 a system with only one CPU, say N. If you have a system with more
363 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100364
Robert Graffham4a474152014-01-23 15:55:29 -0800365 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100366 machines, but will use only one CPU of a multiprocessor machine. If
367 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800368 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100369 will run faster if you say N here.
370
371 Note that if you say Y here and choose architecture "586" or
372 "Pentium" under "Processor family", the kernel will not work on 486
373 architectures. Similarly, multiprocessor kernels for the "PPro"
374 architecture may not work on all Pentium based boards.
375
376 People using multiprocessor machines who say Y here should also say
377 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
378 Management" code will be disabled if you say Y here.
379
Paul Bolle395cf962011-08-15 02:02:26 +0200380 See also <file:Documentation/x86/i386/IO-APIC.txt>,
Benjamin Petersonc9525a32017-05-20 17:20:16 -0700381 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100382 <http://www.tldp.org/docs.html#howto>.
383
384 If you don't know what to do here, say N.
385
Josh Triplett9def39be2013-10-30 08:09:45 -0700386config X86_FEATURE_NAMES
387 bool "Processor feature human-readable names" if EMBEDDED
388 default y
389 ---help---
390 This option compiles in a table of x86 feature bits and corresponding
391 names. This is required to support /proc/cpuinfo and a few kernel
392 messages. You can disable this to save space, at the expense of
393 making those few kernel messages show numeric feature bits instead.
394
395 If in doubt, say Y.
396
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800397config X86_X2APIC
398 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200399 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800400 ---help---
401 This enables x2apic support on CPUs that have this feature.
402
403 This allows 32-bit apic IDs (so it can support very large systems),
404 and accesses the local apic via MSRs not via mmio.
405
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800406 If you don't know what to do here, say N.
407
Yinghai Lu6695c852008-06-19 12:13:09 -0700408config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700409 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000410 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200411 depends on X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100412 ---help---
Yinghai Lu6695c852008-06-19 12:13:09 -0700413 For old smp systems that do not have proper acpi support. Newer systems
414 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700415
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000416config GOLDFISH
417 def_bool y
418 depends on X86_GOLDFISH
419
David Woodhouse76b04382018-01-11 21:46:25 +0000420config RETPOLINE
421 bool "Avoid speculative indirect branches in kernel"
422 default y
Peter Zijlstrad5028ba2018-02-06 09:46:13 +0100423 select STACK_VALIDATION if HAVE_STACK_VALIDATION
David Woodhouse76b04382018-01-11 21:46:25 +0000424 help
425 Compile kernel with the retpoline compiler options to guard against
426 kernel-to-user data leaks by avoiding speculative indirect
427 branches. Requires a compiler with -mindirect-branch=thunk-extern
428 support for full protection. The kernel may run slower.
429
430 Without compiler support, at least indirect branches in assembler
431 code are eliminated. Since this includes the syscall entry path,
432 it is not entirely pointless.
433
Vikas Shivappaf01d7d512017-07-25 14:14:22 -0700434config INTEL_RDT
435 bool "Intel Resource Director Technology support"
Fenghua Yu78e99b42016-10-22 06:19:53 -0700436 default n
437 depends on X86 && CPU_SUP_INTEL
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100438 select KERNFS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700439 help
Vikas Shivappaf01d7d512017-07-25 14:14:22 -0700440 Select to enable resource allocation and monitoring which are
441 sub-features of Intel Resource Director Technology(RDT). More
442 information about RDT can be found in the Intel x86
443 Architecture Software Developer Manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700444
445 Say N if unsure.
446
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800447if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800448config X86_BIGSMP
449 bool "Support for big SMP systems with more than 8 CPUs"
450 depends on SMP
451 ---help---
452 This option is needed for the systems that have more than 8 CPUs
453
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800454config X86_EXTENDED_PLATFORM
455 bool "Support for extended (non-PC) x86 platforms"
456 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100457 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100458 If you disable this option then the kernel will only support
459 standard PC platforms. (which covers the vast majority of
460 systems out there.)
461
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800462 If you enable this option then you'll be able to select support
463 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100464 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800465 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800466 RDC R-321x SoC
467 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200468 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200469 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100470
471 If you have one of these systems, or if you want to build a
472 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800473endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100474
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800475if X86_64
476config X86_EXTENDED_PLATFORM
477 bool "Support for extended (non-PC) x86 platforms"
478 default y
479 ---help---
480 If you disable this option then the kernel will only support
481 standard PC platforms. (which covers the vast majority of
482 systems out there.)
483
484 If you enable this option then you'll be able to select support
485 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800486 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800487 ScaleMP vSMP
488 SGI Ultraviolet
489
490 If you have one of these systems, or if you want to build a
491 generic distribution kernel, say Y here - otherwise say N.
492endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800493# This is an alphabetically sorted list of 64 bit extended platforms
494# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800495config X86_NUMACHIP
496 bool "Numascale NumaChip"
497 depends on X86_64
498 depends on X86_EXTENDED_PLATFORM
499 depends on NUMA
500 depends on SMP
501 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700502 depends on PCI_MMCONFIG
Steffen Persvold44b111b52011-12-06 00:07:26 +0800503 ---help---
504 Adds support for Numascale NumaChip large-SMP systems. Needed to
505 enable more than ~168 cores.
506 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100507
Ingo Molnar6a485652009-01-27 18:29:13 +0100508config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800509 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100510 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100511 select PARAVIRT
512 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800513 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300514 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100515 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100516 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
517 supposed to run on these EM64T-based machines. Only choose this option
518 if you have one of these machines.
519
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800520config X86_UV
521 bool "SGI Ultraviolet"
522 depends on X86_64
523 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500524 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800525 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700526 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200527 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800528 ---help---
529 This option is needed in order to support SGI Ultraviolet systems.
530 If you don't have one of these, you should say N here.
531
532# Following is an alphabetically sorted list of 32 bit extended platforms
533# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100534
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000535config X86_GOLDFISH
536 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100537 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000538 ---help---
539 Enable support for the Goldfish virtual platform used primarily
540 for Android development. Unless you are building for the Android
541 Goldfish emulator say N here.
542
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800543config X86_INTEL_CE
544 bool "CE4100 TV platform"
545 depends on PCI
546 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800547 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800548 depends on X86_32
549 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800550 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100551 select OF
552 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800553 ---help---
554 Select for the Intel CE media processor (CE4100) SOC.
555 This option compiles in support for the CE4100 SOC for settop
556 boxes and media devices.
557
David Cohen4cb9b002013-12-16 17:37:26 -0800558config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100559 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100560 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800561 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000562 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200563 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000564 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000565 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800566 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000567 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000568 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000569 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000570 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000571 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800572 Select to build a kernel capable of supporting Intel MID (Mobile
573 Internet Device) platform systems which do not have the PCI legacy
574 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000575
David Cohen4cb9b002013-12-16 17:37:26 -0800576 Intel MID platforms are based on an Intel processor and chipset which
577 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100578
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000579config X86_INTEL_QUARK
580 bool "Intel Quark platform support"
581 depends on X86_32
582 depends on X86_EXTENDED_PLATFORM
583 depends on X86_PLATFORM_DEVICES
584 depends on X86_TSC
585 depends on PCI
586 depends on PCI_GOANY
587 depends on X86_IO_APIC
588 select IOSF_MBI
589 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200590 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000591 ---help---
592 Select to include support for Quark X1000 SoC.
593 Say Y here if you have a Quark based system such as the Arduino
594 compatible Intel Galileo.
595
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000596config X86_INTEL_LPSS
597 bool "Intel Low Power Subsystem Support"
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100598 depends on X86 && ACPI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000599 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300600 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100601 select IOSF_MBI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000602 ---help---
603 Select to build support for Intel Low Power Subsystem such as
604 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300605 things like clock tree (common clock framework) and pincontrol
606 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000607
Ken Xue92082a82015-02-06 08:27:51 +0800608config X86_AMD_PLATFORM_DEVICE
609 bool "AMD ACPI2Platform devices support"
610 depends on ACPI
611 select COMMON_CLK
612 select PINCTRL
613 ---help---
614 Select to interpret AMD specific ACPI device to platform device
615 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
616 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
617 implemented under PINCTRL subsystem.
618
David E. Boxced3ce72014-09-17 22:13:50 -0700619config IOSF_MBI
620 tristate "Intel SoC IOSF Sideband support for SoC platforms"
621 depends on PCI
622 ---help---
623 This option enables sideband register access support for Intel SoC
624 platforms. On these platforms the IOSF sideband is used in lieu of
625 MSR's for some register accesses, mostly but not limited to thermal
626 and power. Drivers may query the availability of this device to
627 determine if they need the sideband in order to work on these
628 platforms. The sideband is available on the following SoC products.
629 This list is not meant to be exclusive.
630 - BayTrail
631 - Braswell
632 - Quark
633
634 You should say Y if you are running a kernel on one of these SoC's.
635
David E. Boxed2226b2014-09-17 22:13:51 -0700636config IOSF_MBI_DEBUG
637 bool "Enable IOSF sideband access through debugfs"
638 depends on IOSF_MBI && DEBUG_FS
639 ---help---
640 Select this option to expose the IOSF sideband access registers (MCR,
641 MDR, MCRX) through debugfs to write and read register information from
642 different units on the SoC. This is most useful for obtaining device
643 state information for debug and analysis. As this is a general access
644 mechanism, users of this option would have specific knowledge of the
645 device they want to access.
646
647 If you don't require the option or are in doubt, say N.
648
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800649config X86_RDC321X
650 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100651 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800652 depends on X86_EXTENDED_PLATFORM
653 select M486
654 select X86_REBOOTFIXUPS
655 ---help---
656 This option is needed for RDC R-321x system-on-chip, also known
657 as R-8610-(G).
658 If you don't have one of these chips, you should say N here.
659
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100660config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100661 bool "Support non-standard 32-bit SMP architectures"
662 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800663 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100664 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800665 This option compiles in the bigsmp and STA2X11 default
666 subarchitectures. It is intended for a generic binary
667 kernel. If you select them all, kernel will probe it one by
668 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700669
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800670# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700671
Linus Torvaldsd949f362009-09-26 09:35:07 -0700672config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100673 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700674 # MCE code calls memory_failure():
675 depends on X86_MCE
676 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700677 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
678 depends on X86_64 || !SPARSEMEM
679 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700680
Alessandro Rubini83125a32012-04-04 19:40:21 +0200681config STA2X11
682 bool "STA2X11 Companion Chip Support"
683 depends on X86_32_NON_STANDARD && PCI
Christoph Hellwigb6e05472018-03-19 11:38:24 +0100684 select ARCH_HAS_PHYS_TO_DMA
Alessandro Rubini83125a32012-04-04 19:40:21 +0200685 select X86_DEV_DMA_OPS
686 select X86_DMA_REMAP
687 select SWIOTLB
688 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200689 select GPIOLIB
Alessandro Rubini83125a32012-04-04 19:40:21 +0200690 default n
691 ---help---
692 This adds support for boards based on the STA2X11 IO-Hub,
693 a.k.a. "ConneXt". The chip is used in place of the standard
694 PC chipset, so all "standard" peripherals are missing. If this
695 option is selected the kernel will still be able to boot on
696 standard PC machines.
697
Shérab82148d12010-09-25 06:06:57 +0200698config X86_32_IRIS
699 tristate "Eurobraille/Iris poweroff module"
700 depends on X86_32
701 ---help---
702 The Iris machines from EuroBraille do not have APM or ACPI support
703 to shut themselves down properly. A special I/O sequence is
704 needed to do so, which is what this module does at
705 kernel shutdown.
706
707 This is only for Iris machines from EuroBraille.
708
709 If unused, say N.
710
Ingo Molnarae1e9132008-11-11 09:05:16 +0100711config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100712 def_bool y
713 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800714 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100715 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100716 Calculate simpler /proc/<PID>/wchan values. If this option
717 is disabled then wchan values will recurse back to the
718 caller function. This provides more accurate wchan values,
719 at the expense of slightly more scheduling overhead.
720
721 If in doubt, say "Y".
722
Borislav Petkov6276a072013-03-04 21:20:21 +0100723menuconfig HYPERVISOR_GUEST
724 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100725 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100726 Say Y here to enable options for running Linux under various hyper-
727 visors. This option enables basic hypervisor detection and platform
728 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100729
Borislav Petkov6276a072013-03-04 21:20:21 +0100730 If you say N, all options in this submenu will be skipped and
731 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100732
Borislav Petkov6276a072013-03-04 21:20:21 +0100733if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100734
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100735config PARAVIRT
736 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100737 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100738 This changes the kernel so it can modify itself when it is run
739 under a hypervisor, potentially improving performance significantly
740 over full virtualization. However, when run without a hypervisor
741 the kernel is theoretically slower and slightly larger.
742
Borislav Petkov6276a072013-03-04 21:20:21 +0100743config PARAVIRT_DEBUG
744 bool "paravirt-ops debugging"
745 depends on PARAVIRT && DEBUG_KERNEL
746 ---help---
747 Enable to debug paravirt_ops internals. Specifically, BUG if
748 a paravirt_op is missing when it is called.
749
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700750config PARAVIRT_SPINLOCKS
751 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700752 depends on PARAVIRT && SMP
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700753 ---help---
754 Paravirtualized spinlocks allow a pvops backend to replace the
755 spinlock implementation with something virtualization-friendly
756 (for example, block the virtual CPU rather than spinning).
757
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530758 It has a minimal impact on native kernels and gives a nice performance
759 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700760
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530761 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700762
Waiman Long45e898b2015-11-09 19:09:25 -0500763config QUEUED_LOCK_STAT
764 bool "Paravirt queued spinlock statistics"
Peter Zijlstracfd89832016-05-18 20:43:02 +0200765 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
Waiman Long45e898b2015-11-09 19:09:25 -0500766 ---help---
767 Enable the collection of statistical data on the slowpath
768 behavior of paravirtualized queued spinlocks and report
769 them on debugfs.
770
Borislav Petkov6276a072013-03-04 21:20:21 +0100771source "arch/x86/xen/Kconfig"
772
773config KVM_GUEST
774 bool "KVM Guest support (including kvmclock)"
775 depends on PARAVIRT
776 select PARAVIRT_CLOCK
777 default y
778 ---help---
779 This option enables various optimizations for running under the KVM
780 hypervisor. It includes a paravirtualized clock, so that instead
781 of relying on a PIT (or probably other) emulation by the
782 underlying device model, the host provides the guest with
783 timing infrastructure such as time of day, and system time
784
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530785config KVM_DEBUG_FS
786 bool "Enable debug information for KVM Guests in debugfs"
787 depends on KVM_GUEST && DEBUG_FS
788 default n
789 ---help---
790 This option enables collection of various statistics for KVM guest.
791 Statistics are displayed in debugfs filesystem. Enabling this option
792 may incur significant overhead.
793
Borislav Petkov6276a072013-03-04 21:20:21 +0100794config PARAVIRT_TIME_ACCOUNTING
795 bool "Paravirtual steal time accounting"
796 depends on PARAVIRT
797 default n
798 ---help---
799 Select this option to enable fine granularity task steal time
800 accounting. Time spent executing other tasks in parallel with
801 the current vCPU is discounted from the vCPU power. To account for
802 that, there can be a small performance impact.
803
804 If in doubt, say N here.
805
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200806config PARAVIRT_CLOCK
807 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200808
Jan Kiszka4a362602017-11-27 09:11:46 +0100809config JAILHOUSE_GUEST
810 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100811 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100812 select X86_PM_TIMER
Jan Kiszka4a362602017-11-27 09:11:46 +0100813 ---help---
814 This option allows to run Linux as guest in a Jailhouse non-root
815 cell. You can leave this option disabled if you only want to start
816 Jailhouse and run Linux afterwards in the root cell.
817
Borislav Petkov6276a072013-03-04 21:20:21 +0100818endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400819
Yinghai Lu08677212010-02-10 01:20:20 -0800820config NO_BOOTMEM
Yinghai Lu774ea0b2010-08-25 13:39:18 -0700821 def_bool y
Yinghai Lu08677212010-02-10 01:20:20 -0800822
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100823source "arch/x86/Kconfig.cpu"
824
825config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100826 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100827 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100828 ---help---
829 Use the IA-PC HPET (High Precision Event Timer) to manage
830 time in preference to the PIT and RTC, if a HPET is
831 present.
832 HPET is the next generation timer replacing legacy 8254s.
833 The HPET provides a stable time base on SMP
834 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200835 as it is off-chip. The interface used is documented
836 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100837
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100838 You can safely choose Y here. However, HPET will only be
839 activated if the platform and the BIOS support this feature.
840 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100841
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100842 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100843
844config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100845 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800846 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100847
Jacob Panbb24c472009-09-02 07:37:17 -0700848config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000849 def_bool y if X86_INTEL_MID
850 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100851 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000852 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700853 help
854 APB timer is the replacement for 8254, HPET on X86 MID platforms.
855 The APBT provides a stable time base on SMP
856 systems, unlike the TSC, but it is more expensive to access,
857 as it is off-chip. APB timers are always running regardless of CPU
858 C states, they are used as per CPU clockevent device when possible.
859
David Rientjes6a108a12011-01-20 14:44:16 -0800860# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100861# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700862config DMI
863 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800864 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800865 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100866 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700867 Enabled scanning of DMI to identify machine quirks. Say Y
868 here unless you have verified that your setup is not
869 affected by entries in the DMI blacklist. Required by PNP
870 BIOS code.
871
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100872config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700873 bool "Old AMD GART IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200874 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100875 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200876 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100877 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200878 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
879 GART based hardware IOMMUs.
880
881 The GART supports full DMA access for devices with 32-bit access
882 limitations, on systems with more than 3 GB. This is usually needed
883 for USB, sound, many IDE/SATA chipsets and some other devices.
884
885 Newer systems typically have a modern AMD IOMMU, supported via
886 the CONFIG_AMD_IOMMU=y config option.
887
888 In normal configurations this driver is only active when needed:
889 there's more than 3 GB of memory and the system contains a
890 32-bit limited device.
891
892 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100893
894config CALGARY_IOMMU
895 bool "IBM Calgary IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200896 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100897 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700898 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100899 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100900 Support for hardware IOMMUs in IBM's xSeries x366 and x460
901 systems. Needed to run systems with more than 3GB of memory
902 properly with 32-bit PCI devices that do not support DAC
903 (Double Address Cycle). Calgary also supports bus level
904 isolation, where all DMAs pass through the IOMMU. This
905 prevents them from going anywhere except their intended
906 destination. This catches hard-to-find kernel bugs and
907 mis-behaving drivers and devices that do not use the DMA-API
908 properly to set up their DMA buffers. The IOMMU can be
909 turned off at boot time with the iommu=off parameter.
910 Normally the kernel will make the right choice by itself.
911 If unsure, say Y.
912
913config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100914 def_bool y
915 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100916 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100917 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100918 Should Calgary be enabled by default? if you choose 'y', Calgary
919 will be used (if it exists). If you choose 'n', Calgary will not be
920 used even if it exists. If you choose 'n' and would like to use
921 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
922 If unsure, say Y.
923
Mike Travis1184dc22008-05-12 21:21:12 +0200924config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200925 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700926 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800927 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100928 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200929 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200930 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100931
Ingo Molnaraec64872018-02-10 12:36:29 +0100932#
933# The maximum number of CPUs supported:
934#
935# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
936# and which can be configured interactively in the
937# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
938#
939# The ranges are different on 32-bit and 64-bit kernels, depending on
940# hardware capabilities and scalability features of the kernel.
941#
942# ( If MAXSMP is enabled we just use the highest possible value and disable
943# interactive configuration. )
944#
945
946config NR_CPUS_RANGE_BEGIN
947 int
948 default NR_CPUS_RANGE_END if MAXSMP
949 default 1 if !SMP
950 default 2
951
952config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800953 int
954 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100955 default 64 if SMP && X86_BIGSMP
956 default 8 if SMP && !X86_BIGSMP
957 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800958
Ingo Molnaraec64872018-02-10 12:36:29 +0100959config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800960 int
961 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100962 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
963 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
964 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800965
Ingo Molnaraec64872018-02-10 12:36:29 +0100966config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800967 int
968 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100969 default 32 if X86_BIGSMP
970 default 8 if SMP
971 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800972
Ingo Molnaraec64872018-02-10 12:36:29 +0100973config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800974 int
975 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100976 default 8192 if MAXSMP
977 default 64 if SMP
978 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800979
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100980config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800981 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +0100982 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
983 default NR_CPUS_DEFAULT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100984 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100985 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500986 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +0300987 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100988 minimum value which makes sense is 2.
989
Ingo Molnaraec64872018-02-10 12:36:29 +0100990 This is purely to save memory: each supported CPU adds about 8KB
991 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100992
993config SCHED_SMT
994 bool "SMT (Hyperthreading) scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +0200995 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100996 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100997 SMT scheduler support improves the CPU scheduler's decision making
998 when dealing with Intel Pentium 4 chips with HyperThreading at a
999 cost of slightly increased overhead in some places. If unsure say
1000 N here.
1001
1002config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001003 def_bool y
1004 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001005 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001006 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001007 Multi-core scheduler support improves the CPU scheduler's decision
1008 making when dealing with multi-core CPU chips at a cost of slightly
1009 increased overhead in some places. If unsure say N here.
1010
Tim Chende966cf2016-11-29 10:43:27 -08001011config SCHED_MC_PRIO
1012 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001013 depends on SCHED_MC && CPU_SUP_INTEL
1014 select X86_INTEL_PSTATE
1015 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001016 default y
Tim Chen5e76b2a2016-11-22 12:23:55 -08001017 ---help---
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001018 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1019 core ordering determined at manufacturing time, which allows
1020 certain cores to reach higher turbo frequencies (when running
1021 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001022
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001023 Enabling this kernel feature teaches the scheduler about
1024 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1025 scheduler's CPU selection logic accordingly, so that higher
1026 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001027
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001028 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001029
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001030 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001031
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001032source "kernel/Kconfig.preempt"
1033
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001034config UP_LATE_INIT
1035 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +01001036 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001037
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001038config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001039 bool "Local APIC support on uniprocessors" if !PCI_MSI
1040 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001041 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001042 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001043 A local APIC (Advanced Programmable Interrupt Controller) is an
1044 integrated interrupt controller in the CPU. If you have a single-CPU
1045 system which has a processor with a local APIC, you can say Y here to
1046 enable and use it. If you say Y here even though your machine doesn't
1047 have a local APIC, then the kernel will still run with no slowdown at
1048 all. The local APIC supports CPU-generated self-interrupts (timer,
1049 performance counters), and the NMI watchdog which detects hard
1050 lockups.
1051
1052config X86_UP_IOAPIC
1053 bool "IO-APIC support on uniprocessors"
1054 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001055 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001056 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1057 SMP-capable replacement for PC-style interrupt controllers. Most
1058 SMP systems and many recent uniprocessor systems have one.
1059
1060 If you have a single-CPU system with an IO-APIC, you can say Y here
1061 to use it. If you say Y here even though your machine doesn't have
1062 an IO-APIC, then the kernel will still run with no slowdown at all.
1063
1064config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001065 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001066 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001067 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001068 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001069
1070config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001071 def_bool y
1072 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001073
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001074config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1075 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001076 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001077 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001078 This option enables a workaround that fixes a source of
1079 spurious interrupts. This is recommended when threaded
1080 interrupt handling is used on systems where the generation of
1081 superfluous "boot interrupts" cannot be disabled.
1082
1083 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1084 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1085 kernel does during interrupt handling). On chipsets where this
1086 boot IRQ generation cannot be disabled, this workaround keeps
1087 the original IRQ line masked so that only the equivalent "boot
1088 IRQ" is delivered to the CPUs. The workaround also tells the
1089 kernel to set up the IRQ handler on the boot IRQ line. In this
1090 way only one interrupt is delivered to the kernel. Otherwise
1091 the spurious second interrupt may cause the kernel to bring
1092 down (vital) interrupt lines.
1093
1094 Only affects "broken" chipsets. Interrupt sharing may be
1095 increased on these systems.
1096
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001097config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001098 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001099 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001100 default y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001101 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +02001102 Machine Check support allows the processor to notify the
1103 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001104 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001105 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001106
Tony Luck5de97c92017-03-27 11:33:03 +02001107config X86_MCELOG_LEGACY
1108 bool "Support for deprecated /dev/mcelog character device"
1109 depends on X86_MCE
1110 ---help---
1111 Enable support for /dev/mcelog which is needed by the old mcelog
1112 userspace logging daemon. Consider switching to the new generation
1113 rasdaemon solution.
1114
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001115config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001116 def_bool y
1117 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001118 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001119 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001120 Additional support for intel specific MCE features such as
1121 the thermal monitor.
1122
1123config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001124 def_bool y
1125 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001126 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001127 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001128 Additional support for AMD specific MCE features such as
1129 the DRAM Error Threshold.
1130
Andi Kleen4efc0672009-04-28 19:07:31 +02001131config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001132 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001133 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001134 ---help---
1135 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001136 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001137 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001138
Andi Kleenb2762682009-02-12 13:49:31 +01001139config X86_MCE_THRESHOLD
1140 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001141 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001142
Andi Kleenea149b32009-04-29 19:31:00 +02001143config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001144 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001145 tristate "Machine check injector support"
1146 ---help---
1147 Provide support for injecting machine checks for testing purposes.
1148 If you don't know what a machine check is and you don't do kernel
1149 QA it is safe to say n.
1150
Andi Kleen4efc0672009-04-28 19:07:31 +02001151config X86_THERMAL_VECTOR
1152 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001153 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001154
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001155source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001156
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001157config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001158 bool "Legacy VM86 support"
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001159 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001160 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001161 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001162 This option allows user programs to put the CPU into V8086
1163 mode, which is an 80286-era approximation of 16-bit real mode.
1164
1165 Some very old versions of X and/or vbetool require this option
1166 for user mode setting. Similarly, DOSEMU will use it if
1167 available to accelerate real mode DOS programs. However, any
1168 recent version of DOSEMU, X, or vbetool should be fully
1169 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001170 fall back to software emulation. Nevertheless, if you are using
1171 a 16-bit DOS program where 16-bit performance matters, vm86
1172 mode might be faster than emulation and you might want to
1173 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001174
Ingo Molnar1e642812015-09-05 08:58:10 +02001175 Note that any app that works on a 64-bit kernel is unlikely to
1176 need this option, as 64-bit kernels don't, and can't, support
1177 V8086 mode. This option is also unrelated to 16-bit protected
1178 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001179
Ingo Molnar1e642812015-09-05 08:58:10 +02001180 Enabling this option increases the complexity of the kernel
1181 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001182
Ingo Molnar1e642812015-09-05 08:58:10 +02001183 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001184
1185config VM86
1186 bool
1187 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001188
1189config X86_16BIT
1190 bool "Enable support for 16-bit segments" if EXPERT
1191 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001192 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001193 ---help---
1194 This option is required by programs like Wine to run 16-bit
1195 protected mode legacy code on x86 processors. Disabling
1196 this option saves about 300 bytes on i386, or around 6K text
1197 plus 16K runtime memory on x86-64,
1198
1199config X86_ESPFIX32
1200 def_bool y
1201 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001202
H. Peter Anvin197725d2014-05-04 10:00:49 -07001203config X86_ESPFIX64
1204 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001205 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001206
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001207config X86_VSYSCALL_EMULATION
1208 bool "Enable vsyscall emulation" if EXPERT
1209 default y
1210 depends on X86_64
1211 ---help---
1212 This enables emulation of the legacy vsyscall page. Disabling
1213 it is roughly equivalent to booting with vsyscall=none, except
1214 that it will also disable the helpful warning if a program
1215 tries to use a vsyscall. With this option set to N, offending
1216 programs will just segfault, citing addresses of the form
1217 0xffffffffff600?00.
1218
1219 This option is required by many programs built before 2013, and
1220 care should be used even with newer programs if set to N.
1221
1222 Disabling this option saves about 7K of kernel size and
1223 possibly 4K of additional runtime pagetable memory.
1224
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001225config TOSHIBA
1226 tristate "Toshiba Laptop support"
1227 depends on X86_32
1228 ---help---
1229 This adds a driver to safely access the System Management Mode of
1230 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1231 not work on models with a Phoenix BIOS. The System Management Mode
1232 is used to set the BIOS and power saving options on Toshiba portables.
1233
1234 For information on utilities to make use of this driver see the
1235 Toshiba Linux utilities web site at:
1236 <http://www.buzzard.org.uk/toshiba/>.
1237
1238 Say Y if you intend to run this kernel on a Toshiba portable.
1239 Say N otherwise.
1240
1241config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001242 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001243 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001244 select SENSORS_DELL_SMM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001245 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001246 This option enables legacy /proc/i8k userspace interface in hwmon
1247 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1248 temperature and allows controlling fan speeds of Dell laptops via
1249 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1250 it reports also power and hotkey status. For fan speed control is
1251 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001252
Pali Rohár039ae582015-05-14 13:16:37 +02001253 Say Y if you intend to run this kernel on old Dell laptops or want to
1254 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001255 Say N otherwise.
1256
1257config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001258 bool "Enable X86 board specific fixups for reboot"
1259 depends on X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001260 ---help---
1261 This enables chipset and/or board specific fixups to be done
1262 in order to get reboot to work correctly. This is only needed on
1263 some combinations of hardware and BIOS. The symptom, for which
1264 this config is intended, is when reboot ends with a stalled/hung
1265 system.
1266
1267 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001268 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001269
1270 Say Y if you want to enable the fixup. Currently, it's safe to
1271 enable this option even if you don't need it.
1272 Say N otherwise.
1273
1274config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001275 bool "CPU microcode loading support"
1276 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001277 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001278 select FW_LOADER
1279 ---help---
1280 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001281 Intel and AMD processors. The Intel support is for the IA32 family,
1282 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1283 AMD support is for families 0x10 and later. You will obviously need
1284 the actual microcode binary data itself which is not shipped with
1285 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001286
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001287 The preferred method to load microcode from a detached initrd is described
Jaak Ristioja1897a962018-02-09 11:22:16 +02001288 in Documentation/x86/microcode.txt. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001289 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1290 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001291
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001292 In addition, you can build the microcode into the kernel. For that you
1293 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1294 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001295
Peter Oruba8d86f392008-07-28 18:44:21 +02001296config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001297 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001298 depends on MICROCODE
1299 default MICROCODE
1300 select FW_LOADER
1301 ---help---
1302 This options enables microcode patch loading support for Intel
1303 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001304
Alanb8989db2014-01-20 18:01:56 +00001305 For the current Intel microcode data package go to
1306 <https://downloadcenter.intel.com> and search for
1307 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001308
Peter Oruba80cc9f12008-07-28 18:44:22 +02001309config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001310 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001311 depends on MICROCODE
1312 select FW_LOADER
1313 ---help---
1314 If you select this option, microcode patch loading support for AMD
1315 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001316
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001317config MICROCODE_OLD_INTERFACE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001318 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001319 depends on MICROCODE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001320
1321config X86_MSR
1322 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001323 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001324 This device gives privileged processes access to the x86
1325 Model-Specific Registers (MSRs). It is a character device with
1326 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1327 MSR accesses are directed to a specific CPU on multi-processor
1328 systems.
1329
1330config X86_CPUID
1331 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001332 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001333 This device gives processes access to the x86 CPUID instruction to
1334 be executed on a specific processor. It is a character device
1335 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1336 /dev/cpu/31/cpuid.
1337
1338choice
1339 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001340 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001341 depends on X86_32
1342
1343config NOHIGHMEM
1344 bool "off"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001345 ---help---
1346 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1347 However, the address space of 32-bit x86 processors is only 4
1348 Gigabytes large. That means that, if you have a large amount of
1349 physical memory, not all of it can be "permanently mapped" by the
1350 kernel. The physical memory that's not permanently mapped is called
1351 "high memory".
1352
1353 If you are compiling a kernel which will never run on a machine with
1354 more than 1 Gigabyte total physical RAM, answer "off" here (default
1355 choice and suitable for most users). This will result in a "3GB/1GB"
1356 split: 3GB are mapped so that each process sees a 3GB virtual memory
1357 space and the remaining part of the 4GB virtual memory space is used
1358 by the kernel to permanently map as much physical memory as
1359 possible.
1360
1361 If the machine has between 1 and 4 Gigabytes physical RAM, then
1362 answer "4GB" here.
1363
1364 If more than 4 Gigabytes is used then answer "64GB" here. This
1365 selection turns Intel PAE (Physical Address Extension) mode on.
1366 PAE implements 3-level paging on IA32 processors. PAE is fully
1367 supported by Linux, PAE mode is implemented on all recent Intel
1368 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1369 then the kernel will not boot on CPUs that don't support PAE!
1370
1371 The actual amount of total physical memory will either be
1372 auto detected or can be forced by using a kernel command line option
1373 such as "mem=256M". (Try "man bootparam" or see the documentation of
1374 your boot loader (lilo or loadlin) about how to pass options to the
1375 kernel at boot time.)
1376
1377 If unsure, say "off".
1378
1379config HIGHMEM4G
1380 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001381 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001382 Select this if you have a 32-bit processor and between 1 and 4
1383 gigabytes of physical RAM.
1384
1385config HIGHMEM64G
1386 bool "64GB"
Matthew Whitehead69b8d3f2018-02-15 11:54:55 -05001387 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001388 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001389 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001390 Select this if you have a 32-bit processor and more than 4
1391 gigabytes of physical RAM.
1392
1393endchoice
1394
1395choice
David Rientjes6a108a12011-01-20 14:44:16 -08001396 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001397 default VMSPLIT_3G
1398 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001399 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001400 Select the desired split between kernel and user memory.
1401
1402 If the address range available to the kernel is less than the
1403 physical memory installed, the remaining memory will be available
1404 as "high memory". Accessing high memory is a little more costly
1405 than low memory, as it needs to be mapped into the kernel first.
1406 Note that increasing the kernel address space limits the range
1407 available to user programs, making the address space there
1408 tighter. Selecting anything other than the default 3G/1G split
1409 will also likely make your kernel incompatible with binary-only
1410 kernel modules.
1411
1412 If you are not absolutely sure what you are doing, leave this
1413 option alone!
1414
1415 config VMSPLIT_3G
1416 bool "3G/1G user/kernel split"
1417 config VMSPLIT_3G_OPT
1418 depends on !X86_PAE
1419 bool "3G/1G user/kernel split (for full 1G low memory)"
1420 config VMSPLIT_2G
1421 bool "2G/2G user/kernel split"
1422 config VMSPLIT_2G_OPT
1423 depends on !X86_PAE
1424 bool "2G/2G user/kernel split (for full 2G low memory)"
1425 config VMSPLIT_1G
1426 bool "1G/3G user/kernel split"
1427endchoice
1428
1429config PAGE_OFFSET
1430 hex
1431 default 0xB0000000 if VMSPLIT_3G_OPT
1432 default 0x80000000 if VMSPLIT_2G
1433 default 0x78000000 if VMSPLIT_2G_OPT
1434 default 0x40000000 if VMSPLIT_1G
1435 default 0xC0000000
1436 depends on X86_32
1437
1438config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001439 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001440 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001441
1442config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001443 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001444 depends on X86_32 && !HIGHMEM4G
Christoph Hellwigd4a451d2018-04-03 16:24:20 +02001445 select PHYS_ADDR_T_64BIT
Christian Melki9d99c712015-10-05 17:31:33 +02001446 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001447 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001448 PAE is required for NX support, and furthermore enables
1449 larger swapspace support for non-overcommit purposes. It
1450 has the cost of more pagetable lookup overhead, and also
1451 consumes more pagetable space per process.
1452
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001453config X86_5LEVEL
1454 bool "Enable 5-level page tables support"
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001455 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001456 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001457 depends on X86_64
1458 ---help---
1459 5-level paging enables access to larger address space:
1460 upto 128 PiB of virtual address space and 4 PiB of
1461 physical address space.
1462
1463 It will be supported by future Intel CPUs.
1464
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001465 A kernel with the option enabled can be booted on machines that
1466 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001467
1468 See Documentation/x86/x86_64/5level-paging.txt for more
1469 information.
1470
1471 Say N if unsure.
1472
Ingo Molnar10971ab2015-03-05 08:18:23 +01001473config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001474 def_bool y
Levin, Alexander (Sasha Levin)4675ff02017-11-15 17:36:02 -08001475 depends on X86_64 && !DEBUG_PAGEALLOC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001476 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001477 Certain kernel features effectively disable kernel
1478 linear 1 GB mappings (even if the CPU otherwise
1479 supports them), so don't confuse the user by printing
1480 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001481
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001482config ARCH_HAS_MEM_ENCRYPT
1483 def_bool y
1484
1485config AMD_MEM_ENCRYPT
1486 bool "AMD Secure Memory Encryption (SME) support"
1487 depends on X86_64 && CPU_SUP_AMD
1488 ---help---
1489 Say yes to enable support for the encryption of system memory.
1490 This requires an AMD processor that supports Secure Memory
1491 Encryption (SME).
1492
1493config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1494 bool "Activate AMD Secure Memory Encryption (SME) by default"
1495 default y
1496 depends on AMD_MEM_ENCRYPT
1497 ---help---
1498 Say yes to have system memory encrypted by default if running on
1499 an AMD processor that supports Secure Memory Encryption (SME).
1500
1501 If set to Y, then the encryption of system memory can be
1502 deactivated with the mem_encrypt=off command line option.
1503
1504 If set to N, then the encryption of system memory can be
1505 activated with the mem_encrypt=on command line option.
1506
Tom Lendackyf88a68f2017-07-17 16:10:09 -05001507config ARCH_USE_MEMREMAP_PROT
1508 def_bool y
1509 depends on AMD_MEM_ENCRYPT
1510
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001511# Common NUMA Features
1512config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001513 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001514 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001515 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1516 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001517 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001518 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001519
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001520 The kernel will try to allocate memory used by a CPU on the
1521 local memory controller of the CPU and add some more
1522 NUMA awareness to the kernel.
1523
Ingo Molnarc280ea52008-11-08 13:29:45 +01001524 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001525 (or later), AMD Opteron, or EM64T NUMA.
1526
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001527 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001528 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001529
1530 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001531
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001532config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001533 def_bool y
1534 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001535 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001536 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001537 Enable AMD NUMA node topology detection. You should say Y here if
1538 you have a multi processor AMD system. This uses an old method to
1539 read the NUMA configuration directly from the builtin Northbridge
1540 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1541 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001542
1543config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001544 def_bool y
1545 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001546 depends on X86_64 && NUMA && ACPI && PCI
1547 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001548 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001549 Enable ACPI SRAT based node topology detection.
1550
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001551# Some NUMA nodes have memory ranges that span
1552# other nodes. Even though a pfn is valid and
1553# between a node's start and end pfns, it may not
1554# reside on that node. See memmap_init_zone()
1555# for details.
1556config NODES_SPAN_OTHER_NODES
1557 def_bool y
1558 depends on X86_64_ACPI_NUMA
1559
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001560config NUMA_EMU
1561 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001562 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001563 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001564 Enable NUMA emulation. A flat machine will be split
1565 into virtual nodes when booted with "numa=fake=N", where N is the
1566 number of nodes. This is only useful for debugging.
1567
1568config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001569 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001570 range 1 10
1571 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001572 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001573 default "3"
1574 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001575 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001576 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001577 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001578
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001579config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001580 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001581 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001582
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001583config ARCH_FLATMEM_ENABLE
1584 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001585 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001586
1587config ARCH_DISCONTIGMEM_ENABLE
1588 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001589 depends on NUMA && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001590
1591config ARCH_DISCONTIGMEM_DEFAULT
1592 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001593 depends on NUMA && X86_32
1594
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001595config ARCH_SPARSEMEM_ENABLE
1596 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001597 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001598 select SPARSEMEM_STATIC if X86_32
1599 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1600
Tejun Heo3b166512011-04-01 11:15:12 +02001601config ARCH_SPARSEMEM_DEFAULT
1602 def_bool y
1603 depends on X86_64
1604
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001605config ARCH_SELECT_MEMORY_MODEL
1606 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001607 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001608
1609config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001610 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001611 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001612 help
1613 This option enables a sysfs memory/probe interface for testing.
1614 See Documentation/memory-hotplug.txt for more information.
1615 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001616
Tejun Heo3b166512011-04-01 11:15:12 +02001617config ARCH_PROC_KCORE_TEXT
1618 def_bool y
1619 depends on X86_64 && PROC_KCORE
1620
Avi Kivitya29815a2010-01-10 16:28:09 +02001621config ILLEGAL_POINTER_VALUE
1622 hex
1623 default 0 if X86_32
1624 default 0xdead000000000000 if X86_64
1625
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001626source "mm/Kconfig"
1627
Dan Williams7a678322015-08-19 00:34:34 -04001628config X86_PMEM_LEGACY_DEVICE
1629 bool
1630
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001631config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001632 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001633 depends on PHYS_ADDR_T_64BIT
1634 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001635 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001636 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001637 help
1638 Treat memory marked using the non-standard e820 type of 12 as used
1639 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1640 The kernel will offer these regions to the 'pmem' driver so
1641 they can be used for persistent storage.
1642
1643 Say Y if unsure.
1644
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001645config HIGHPTE
1646 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001647 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001648 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001649 The VM uses one page table entry for each page of physical memory.
1650 For systems with a lot of RAM, this can be wasteful of precious
1651 low memory. Setting this option will put user-space page table
1652 entries in high memory.
1653
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001654config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001655 bool "Check for low memory corruption"
1656 ---help---
1657 Periodically check for memory corruption in low memory, which
1658 is suspected to be caused by BIOS. Even when enabled in the
1659 configuration, it is disabled at runtime. Enable it by
1660 setting "memory_corruption_check=1" on the kernel command
1661 line. By default it scans the low 64k of memory every 60
1662 seconds; see the memory_corruption_check_size and
1663 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001664 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001665
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001666 When enabled with the default parameters, this option has
1667 almost no overhead, as it reserves a relatively small amount
1668 of memory and scans it infrequently. It both detects corruption
1669 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001670
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001671 It is, however, intended as a diagnostic tool; if repeatable
1672 BIOS-originated corruption always affects the same memory,
1673 you can use memmap= to prevent the kernel from using that
1674 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001675
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001676config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001677 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001678 depends on X86_CHECK_BIOS_CORRUPTION
1679 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001680 ---help---
1681 Set whether the default state of memory_corruption_check is
1682 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001683
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001684config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001685 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1686 default 64
1687 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001688 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001689 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001690
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001691 The first page contains BIOS data structures that the kernel
1692 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001693
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001694 By default we reserve the first 64K of physical RAM, as a
1695 number of BIOSes are known to corrupt that memory range
1696 during events such as suspend/resume or monitor cable
1697 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001698
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001699 You can set this to 4 if you are absolutely sure that you
1700 trust the BIOS to get all its memory reservations and usages
1701 right. If you know your BIOS have problems beyond the
1702 default 64K area, you can set this to 640 to avoid using the
1703 entire low memory range.
1704
1705 If you have doubts about the BIOS (e.g. suspend/resume does
1706 not work or there's kernel crashes after certain hardware
1707 hotplug events) then you might want to enable
1708 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1709 typical corruption patterns.
1710
1711 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001712
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001713config MATH_EMULATION
1714 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001715 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001716 prompt "Math emulation" if X86_32
1717 ---help---
1718 Linux can emulate a math coprocessor (used for floating point
1719 operations) if you don't have one. 486DX and Pentium processors have
1720 a math coprocessor built in, 486SX and 386 do not, unless you added
1721 a 487DX or 387, respectively. (The messages during boot time can
1722 give you some hints here ["man dmesg"].) Everyone needs either a
1723 coprocessor or this emulation.
1724
1725 If you don't have a math coprocessor, you need to say Y here; if you
1726 say Y here even though you have a coprocessor, the coprocessor will
1727 be used nevertheless. (This behavior can be changed with the kernel
1728 command line option "no387", which comes handy if your coprocessor
1729 is broken. Try "man bootparam" or see the documentation of your boot
1730 loader (lilo or loadlin) about how to pass options to the kernel at
1731 boot time.) This means that it is a good idea to say Y here if you
1732 intend to use this kernel on different machines.
1733
1734 More information about the internals of the Linux math coprocessor
1735 emulation can be found in <file:arch/x86/math-emu/README>.
1736
1737 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1738 kernel, it won't hurt.
1739
1740config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001741 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001742 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001743 ---help---
1744 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1745 the Memory Type Range Registers (MTRRs) may be used to control
1746 processor access to memory ranges. This is most useful if you have
1747 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1748 allows bus write transfers to be combined into a larger transfer
1749 before bursting over the PCI/AGP bus. This can increase performance
1750 of image write operations 2.5 times or more. Saying Y here creates a
1751 /proc/mtrr file which may be used to manipulate your processor's
1752 MTRRs. Typically the X server should use this.
1753
1754 This code has a reasonably generic interface so that similar
1755 control registers on other processors can be easily supported
1756 as well:
1757
1758 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1759 Registers (ARRs) which provide a similar functionality to MTRRs. For
1760 these, the ARRs are used to emulate the MTRRs.
1761 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1762 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1763 write-combining. All of these processors are supported by this code
1764 and it makes sense to say Y here if you have one of them.
1765
1766 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1767 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1768 can lead to all sorts of problems, so it's good to say Y here.
1769
1770 You can safely say Y even if your machine doesn't have MTRRs, you'll
1771 just add about 9 KB to your kernel.
1772
Randy Dunlap7225e752008-07-26 17:54:22 -07001773 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001774
Yinghai Lu95ffa242008-04-29 03:52:33 -07001775config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001776 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001777 prompt "MTRR cleanup support"
1778 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001779 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001780 Convert MTRR layout from continuous to discrete, so X drivers can
1781 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001782
Thomas Gleixneraba37282008-07-15 14:48:48 +02001783 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001784 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001785 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001786
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001787 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001788
1789config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001790 int "MTRR cleanup enable value (0-1)"
1791 range 0 1
1792 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001793 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001794 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001795 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001796
Yinghai Lu12031a62008-05-02 02:40:22 -07001797config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1798 int "MTRR cleanup spare reg num (0-7)"
1799 range 0 7
1800 default "1"
1801 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001802 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001803 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001804 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001805
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001806config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001807 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001808 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001809 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001810 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001811 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001812
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001813 PATs are the modern equivalents of MTRRs and are much more
1814 flexible than MTRRs.
1815
1816 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001817 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001818
1819 If unsure, say Y.
1820
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001821config ARCH_USES_PG_UNCACHED
1822 def_bool y
1823 depends on X86_PAT
1824
H. Peter Anvin628c6242011-07-31 13:59:29 -07001825config ARCH_RANDOM
1826 def_bool y
1827 prompt "x86 architectural random number generator" if EXPERT
1828 ---help---
1829 Enable the x86 architectural RDRAND instruction
1830 (Intel Bull Mountain technology) to generate random numbers.
1831 If supported, this is a high bandwidth, cryptographically
1832 secure hardware random number generator.
1833
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001834config X86_SMAP
1835 def_bool y
1836 prompt "Supervisor Mode Access Prevention" if EXPERT
1837 ---help---
1838 Supervisor Mode Access Prevention (SMAP) is a security
1839 feature in newer Intel processors. There is a small
1840 performance cost if this enabled and turned on; there is
1841 also a small increase in the kernel size if this is enabled.
1842
1843 If unsure, say Y.
1844
Ricardo Neriaa35f892017-11-05 18:27:54 -08001845config X86_INTEL_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001846 def_bool y
Ricardo Neriaa35f892017-11-05 18:27:54 -08001847 depends on CPU_SUP_INTEL
1848 prompt "Intel User Mode Instruction Prevention" if EXPERT
1849 ---help---
1850 The User Mode Instruction Prevention (UMIP) is a security
1851 feature in newer Intel processors. If enabled, a general
Ricardo Neri796ebc82017-11-13 22:29:42 -08001852 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1853 or STR instructions are executed in user mode. These instructions
1854 unnecessarily expose information about the hardware state.
1855
1856 The vast majority of applications do not use these instructions.
1857 For the very few that do, software emulation is provided in
1858 specific cases in protected and virtual-8086 modes. Emulated
1859 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001860
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001861config X86_INTEL_MPX
1862 prompt "Intel MPX (Memory Protection Extensions)"
1863 def_bool n
Rik van Rieldf3735c2017-09-06 16:25:11 -07001864 # Note: only available in 64-bit mode due to VMA flags shortage
1865 depends on CPU_SUP_INTEL && X86_64
1866 select ARCH_USES_HIGH_VMA_FLAGS
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001867 ---help---
1868 MPX provides hardware features that can be used in
1869 conjunction with compiler-instrumented code to check
1870 memory references. It is designed to detect buffer
1871 overflow or underflow bugs.
1872
1873 This option enables running applications which are
1874 instrumented or otherwise use MPX. It does not use MPX
1875 itself inside the kernel or to protect the kernel
1876 against bad memory references.
1877
1878 Enabling this option will make the kernel larger:
1879 ~8k of kernel text and 36 bytes of data on a 64-bit
1880 defconfig. It adds a long to the 'mm_struct' which
1881 will increase the kernel memory overhead of each
1882 process and adds some branches to paths used during
1883 exec() and munmap().
1884
1885 For details, see Documentation/x86/intel_mpx.txt
1886
1887 If unsure, say N.
1888
Dave Hansen35e97792016-02-12 13:02:00 -08001889config X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001890 prompt "Intel Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001891 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001892 # Note: only available in 64-bit mode
Dave Hansen35e97792016-02-12 13:02:00 -08001893 depends on CPU_SUP_INTEL && X86_64
Ingo Molnar52c8e602016-11-15 10:15:03 +01001894 select ARCH_USES_HIGH_VMA_FLAGS
1895 select ARCH_HAS_PKEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001896 ---help---
1897 Memory Protection Keys provides a mechanism for enforcing
1898 page-based protections, but without requiring modification of the
1899 page tables when an application changes protection domains.
1900
1901 For details, see Documentation/x86/protection-keys.txt
1902
1903 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001904
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001905config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001906 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001907 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001908 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001909 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001910 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001911 This enables the kernel to use EFI runtime services that are
1912 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001913
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001914 This option is only useful on systems that have EFI firmware.
1915 In addition, you should use the latest ELILO loader available
1916 at <http://elilo.sourceforge.net> in order to take advantage
1917 of EFI runtime services. However, even with this option, the
1918 resultant kernel should continue to boot on existing non-EFI
1919 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001920
Matt Fleming291f3632011-12-12 21:27:52 +00001921config EFI_STUB
1922 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001923 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001924 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001925 ---help---
1926 This kernel feature allows a bzImage to be loaded directly
1927 by EFI firmware without the use of a bootloader.
1928
Roy Franz4172fe22013-09-22 15:45:25 -07001929 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001930
Matt Fleming7d453ee2014-01-10 18:52:06 +00001931config EFI_MIXED
1932 bool "EFI mixed-mode support"
1933 depends on EFI_STUB && X86_64
1934 ---help---
1935 Enabling this feature allows a 64-bit kernel to be booted
1936 on a 32-bit firmware, provided that your CPU supports 64-bit
1937 mode.
1938
1939 Note that it is not possible to boot a mixed-mode enabled
1940 kernel via the EFI boot stub - a bootloader that supports
1941 the EFI handover protocol must be used.
1942
1943 If unsure, say N.
1944
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001945config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001946 def_bool y
1947 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001948 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001949 This kernel feature is useful for number crunching applications
1950 that may need to compute untrusted bytecode during their
1951 execution. By using pipes or other transports made available to
1952 the process as file descriptors supporting the read/write
1953 syscalls, it's possible to isolate those applications in
1954 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001955 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001956 and the task is only allowed to execute a few safe syscalls
1957 defined by each seccomp mode.
1958
1959 If unsure, say Y. Only embedded should say N here.
1960
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001961source kernel/Kconfig.hz
1962
1963config KEXEC
1964 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001965 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001966 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001967 kexec is a system call that implements the ability to shutdown your
1968 current kernel, and to start another kernel. It is like a reboot
1969 but it is independent of the system firmware. And like a reboot
1970 you can start any kernel with it, not just Linux.
1971
1972 The name comes from the similarity to the exec system call.
1973
1974 It is an ongoing process to be certain the hardware in a machine
1975 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001976 initially work for you. As of this writing the exact hardware
1977 interface is strongly in flux, so no good recommendation can be
1978 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001979
Vivek Goyal74ca3172014-08-29 15:18:46 -07001980config KEXEC_FILE
1981 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07001982 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07001983 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07001984 depends on X86_64
1985 depends on CRYPTO=y
1986 depends on CRYPTO_SHA256=y
1987 ---help---
1988 This is new version of kexec system call. This system call is
1989 file based and takes file descriptors as system call argument
1990 for kernel and initramfs as opposed to list of segments as
1991 accepted by previous system call.
1992
AKASHI Takahirob799a092018-04-13 15:35:45 -07001993config ARCH_HAS_KEXEC_PURGATORY
1994 def_bool KEXEC_FILE
1995
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001996config KEXEC_VERIFY_SIG
1997 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07001998 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001999 ---help---
2000 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002001 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002002
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002003 In addition to that option, you need to enable signature
2004 verification for the corresponding kernel image type being
2005 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002006
2007config KEXEC_BZIMAGE_VERIFY_SIG
2008 bool "Enable bzImage signature verification support"
2009 depends on KEXEC_VERIFY_SIG
2010 depends on SIGNED_PE_FILE_VERIFICATION
2011 select SYSTEM_TRUSTED_KEYRING
2012 ---help---
2013 Enable bzImage signature verification support.
2014
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002015config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002016 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002017 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002018 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002019 Generate crash dump after being started by kexec.
2020 This should be normally only set in special crash dump kernels
2021 which are loaded in the main kernel with kexec-tools into
2022 a specially reserved region and then later executed after
2023 a crash by kdump/kexec. The crash dump kernel must be compiled
2024 to a memory address not used by the main kernel or BIOS using
2025 PHYSICAL_START, or it must be built as a relocatable image
2026 (CONFIG_RELOCATABLE=y).
2027 For more details see Documentation/kdump/kdump.txt
2028
Huang Ying3ab83522008-07-25 19:45:07 -07002029config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002030 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002031 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002032 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07002033 Jump between original kernel and kexeced kernel and invoke
2034 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002035
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002036config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002037 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002038 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002039 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002040 This gives the physical address where the kernel is loaded.
2041
2042 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2043 bzImage will decompress itself to above physical address and
2044 run from there. Otherwise, bzImage will run from the address where
2045 it has been loaded by the boot loader and will ignore above physical
2046 address.
2047
2048 In normal kdump cases one does not have to set/change this option
2049 as now bzImage can be compiled as a completely relocatable image
2050 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2051 address. This option is mainly useful for the folks who don't want
2052 to use a bzImage for capturing the crash dump and want to use a
2053 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2054 to be specifically compiled to run from a specific memory area
2055 (normally a reserved region) and this option comes handy.
2056
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002057 So if you are using bzImage for capturing the crash dump,
2058 leave the value here unchanged to 0x1000000 and set
2059 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2060 for capturing the crash dump change this value to start of
2061 the reserved region. In other words, it can be set based on
2062 the "X" value as specified in the "crashkernel=YM@XM"
2063 command line boot parameter passed to the panic-ed
2064 kernel. Please take a look at Documentation/kdump/kdump.txt
2065 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002066
2067 Usage of bzImage for capturing the crash dump is recommended as
2068 one does not have to build two kernels. Same kernel can be used
2069 as production kernel and capture kernel. Above option should have
2070 gone away after relocatable bzImage support is introduced. But it
2071 is present because there are users out there who continue to use
2072 vmlinux for dump capture. This option should go away down the
2073 line.
2074
2075 Don't change this unless you know what you are doing.
2076
2077config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002078 bool "Build a relocatable kernel"
2079 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002080 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002081 This builds a kernel image that retains relocation information
2082 so it can be loaded someplace besides the default 1MB.
2083 The relocations tend to make the kernel binary about 10% larger,
2084 but are discarded at runtime.
2085
2086 One use is for the kexec on panic case where the recovery kernel
2087 must live at a different physical address than the primary
2088 kernel.
2089
2090 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2091 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002092 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002093
Kees Cook8ab38202013-10-10 17:18:14 -07002094config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002095 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002096 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002097 default y
Kees Cook8ab38202013-10-10 17:18:14 -07002098 ---help---
Baoquan Hee8581e32016-04-20 13:55:43 -07002099 In support of Kernel Address Space Layout Randomization (KASLR),
2100 this randomizes the physical address at which the kernel image
2101 is decompressed and the virtual address where the kernel
2102 image is mapped, as a security feature that deters exploit
2103 attempts relying on knowledge of the location of kernel
2104 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002105
Kees Cooked9f0072016-05-25 15:45:33 -07002106 On 64-bit, the kernel physical and virtual addresses are
2107 randomized separately. The physical address will be anywhere
2108 between 16MB and the top of physical memory (up to 64TB). The
2109 virtual address will be randomized from 16MB up to 1GB (9 bits
2110 of entropy). Note that this also reduces the memory space
2111 available to kernel modules from 1.5GB to 1GB.
2112
2113 On 32-bit, the kernel physical and virtual addresses are
2114 randomized together. They will be randomized from 16MB up to
2115 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002116
Baoquan Hee8581e32016-04-20 13:55:43 -07002117 Entropy is generated using the RDRAND instruction if it is
2118 supported. If RDTSC is supported, its value is mixed into
2119 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002120 supported, then entropy is read from the i8254 timer. The
2121 usable entropy is limited by the kernel being built using
2122 2GB addressing, and that PHYSICAL_ALIGN must be at a
2123 minimum of 2MB. As a result, only 10 bits of entropy are
2124 theoretically possible, but the implementations are further
2125 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002126
Ingo Molnar6807c842017-04-18 11:08:12 +02002127 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002128
2129# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002130config X86_NEED_RELOCS
2131 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002132 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002133
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002134config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002135 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002136 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002137 range 0x2000 0x1000000 if X86_32
2138 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002139 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002140 This value puts the alignment restrictions on physical address
2141 where kernel is loaded and run from. Kernel is compiled for an
2142 address which meets above alignment restriction.
2143
2144 If bootloader loads the kernel at a non-aligned address and
2145 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2146 address aligned to above value and run from there.
2147
2148 If bootloader loads the kernel at a non-aligned address and
2149 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2150 load address and decompress itself to the address it has been
2151 compiled for and run from there. The address for which kernel is
2152 compiled already meets above alignment restrictions. Hence the
2153 end result is that kernel runs from a physical address meeting
2154 above alignment restrictions.
2155
Kees Cooka0215062013-07-08 09:15:17 -07002156 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2157 this value must be a multiple of 0x200000.
2158
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002159 Don't change this unless you know what you are doing.
2160
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002161config DYNAMIC_MEMORY_LAYOUT
2162 bool
2163 ---help---
2164 This option makes base addresses of vmalloc and vmemmap as well as
2165 __PAGE_OFFSET movable during boot.
2166
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002167config RANDOMIZE_MEMORY
2168 bool "Randomize the kernel memory sections"
2169 depends on X86_64
2170 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002171 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002172 default RANDOMIZE_BASE
2173 ---help---
2174 Randomizes the base virtual address of kernel memory sections
2175 (physical memory mapping, vmalloc & vmemmap). This security feature
2176 makes exploits relying on predictable memory locations less reliable.
2177
2178 The order of allocations remains unchanged. Entropy is generated in
2179 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2180 configuration have in average 30,000 different possible virtual
2181 addresses for each memory section.
2182
Ingo Molnar6807c842017-04-18 11:08:12 +02002183 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002184
Thomas Garnier90397a42016-06-21 17:47:06 -07002185config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2186 hex "Physical memory mapping padding" if EXPERT
2187 depends on RANDOMIZE_MEMORY
2188 default "0xa" if MEMORY_HOTPLUG
2189 default "0x0"
2190 range 0x1 0x40 if MEMORY_HOTPLUG
2191 range 0x0 0x40
2192 ---help---
2193 Define the padding in terabytes added to the existing physical
2194 memory size during kernel memory randomization. It is useful
2195 for memory hotplug support but reduces the entropy available for
2196 address randomization.
2197
2198 If unsure, leave at the default value.
2199
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002200config HOTPLUG_CPU
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002201 bool "Support for hot-pluggable CPUs"
Stephen Rothwell40b31362013-05-21 13:49:35 +10002202 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002203 ---help---
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002204 Say Y here to allow turning CPUs off and on. CPUs can be
2205 controlled through /sys/devices/system/cpu.
2206 ( Note: power management support will enable this option
2207 automatically on SMP systems. )
2208 Say N if you want to disable CPU hotplug.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002209
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002210config BOOTPARAM_HOTPLUG_CPU0
2211 bool "Set default setting of cpu0_hotpluggable"
2212 default n
Kees Cook2c922cd2013-01-22 13:01:19 -08002213 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002214 ---help---
2215 Set whether default state of cpu0_hotpluggable is on or off.
2216
2217 Say Y here to enable CPU0 hotplug by default. If this switch
2218 is turned on, there is no need to give cpu0_hotplug kernel
2219 parameter and the CPU0 hotplug feature is enabled by default.
2220
2221 Please note: there are two known CPU0 dependencies if you want
2222 to enable the CPU0 hotplug feature either by this switch or by
2223 cpu0_hotplug kernel parameter.
2224
2225 First, resume from hibernate or suspend always starts from CPU0.
2226 So hibernate and suspend are prevented if CPU0 is offline.
2227
2228 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2229 offline if any interrupt can not migrate out of CPU0. There may
2230 be other CPU0 dependencies.
2231
2232 Please make sure the dependencies are under your control before
2233 you enable this feature.
2234
2235 Say N if you don't want to enable CPU0 hotplug feature by default.
2236 You still can enable the CPU0 hotplug feature at boot by kernel
2237 parameter cpu0_hotplug.
2238
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002239config DEBUG_HOTPLUG_CPU0
2240 def_bool n
2241 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002242 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002243 ---help---
2244 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2245 soon as possible and boots up userspace with CPU0 offlined. User
2246 can online CPU0 back after boot time.
2247
2248 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2249 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2250 compilation or giving cpu0_hotplug kernel parameter at boot.
2251
2252 If unsure, say N.
2253
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002254config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002255 def_bool n
2256 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002257 depends on COMPAT_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002258 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002259 Certain buggy versions of glibc will crash if they are
2260 presented with a 32-bit vDSO that is not mapped at the address
2261 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002262
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002263 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2264 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2265 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2266 the only released version with the bug, but OpenSUSE 9
2267 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002268
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002269 The symptom of the bug is that everything crashes on startup, saying:
2270 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2271
2272 Saying Y here changes the default value of the vdso32 boot
2273 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2274 This works around the glibc bug but hurts performance.
2275
2276 If unsure, say N: if you are compiling your own kernel, you
2277 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002278
Kees Cook3dc33bd2015-08-12 17:55:19 -07002279choice
2280 prompt "vsyscall table for legacy applications"
2281 depends on X86_64
2282 default LEGACY_VSYSCALL_EMULATE
2283 help
2284 Legacy user code that does not know how to find the vDSO expects
2285 to be able to issue three syscalls by calling fixed addresses in
2286 kernel space. Since this location is not randomized with ASLR,
2287 it can be used to assist security vulnerability exploitation.
2288
2289 This setting can be changed at boot time via the kernel command
Andy Lutomirski076ca272018-03-07 11:12:27 -08002290 line parameter vsyscall=[emulate|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002291
2292 On a system with recent enough glibc (2.14 or newer) and no
2293 static binaries, you can say None without a performance penalty
2294 to improve security.
2295
2296 If unsure, select "Emulate".
2297
Kees Cook3dc33bd2015-08-12 17:55:19 -07002298 config LEGACY_VSYSCALL_EMULATE
2299 bool "Emulate"
2300 help
2301 The kernel traps and emulates calls into the fixed
2302 vsyscall address mapping. This makes the mapping
2303 non-executable, but it still contains known contents,
2304 which could be used in certain rare security vulnerability
2305 exploits. This configuration is recommended when userspace
2306 still uses the vsyscall area.
2307
2308 config LEGACY_VSYSCALL_NONE
2309 bool "None"
2310 help
2311 There will be no vsyscall mapping at all. This will
2312 eliminate any risk of ASLR bypass due to the vsyscall
2313 fixed address mapping. Attempts to use the vsyscalls
2314 will be reported to dmesg, so that either old or
2315 malicious userspace programs can be identified.
2316
2317endchoice
2318
Tim Bird516cbf32008-08-12 12:52:36 -07002319config CMDLINE_BOOL
2320 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002321 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002322 Allow for specifying boot arguments to the kernel at
2323 build time. On some systems (e.g. embedded ones), it is
2324 necessary or convenient to provide some or all of the
2325 kernel boot arguments with the kernel itself (that is,
2326 to not rely on the boot loader to provide them.)
2327
2328 To compile command line arguments into the kernel,
2329 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002330 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002331
2332 Systems with fully functional boot loaders (i.e. non-embedded)
2333 should leave this option set to 'N'.
2334
2335config CMDLINE
2336 string "Built-in kernel command string"
2337 depends on CMDLINE_BOOL
2338 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002339 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002340 Enter arguments here that should be compiled into the kernel
2341 image and used at boot time. If the boot loader provides a
2342 command line at boot time, it is appended to this string to
2343 form the full kernel command line, when the system boots.
2344
2345 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2346 change this behavior.
2347
2348 In most cases, the command line (whether built-in or provided
2349 by the boot loader) should specify the device for the root
2350 file system.
2351
2352config CMDLINE_OVERRIDE
2353 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002354 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002355 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002356 Set this option to 'Y' to have the kernel ignore the boot loader
2357 command line, and use ONLY the built-in command line.
2358
2359 This is used to work around broken boot loaders. This should
2360 be set to 'N' under normal conditions.
2361
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002362config MODIFY_LDT_SYSCALL
2363 bool "Enable the LDT (local descriptor table)" if EXPERT
2364 default y
2365 ---help---
2366 Linux can allow user programs to install a per-process x86
2367 Local Descriptor Table (LDT) using the modify_ldt(2) system
2368 call. This is required to run 16-bit or segmented code such as
2369 DOSEMU or some Wine programs. It is also used by some very old
2370 threading libraries.
2371
2372 Enabling this feature adds a small amount of overhead to
2373 context switches and increases the low-level kernel attack
2374 surface. Disabling it removes the modify_ldt(2) system call.
2375
2376 Saying 'N' here may make sense for embedded or server kernels.
2377
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002378source "kernel/livepatch/Kconfig"
2379
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002380endmenu
2381
Michal Hocko3072e412017-09-08 16:11:39 -07002382config ARCH_HAS_ADD_PAGES
2383 def_bool y
2384 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2385
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002386config ARCH_ENABLE_MEMORY_HOTPLUG
2387 def_bool y
2388 depends on X86_64 || (X86_32 && HIGHMEM)
2389
Gary Hade35551052008-10-31 10:52:03 -07002390config ARCH_ENABLE_MEMORY_HOTREMOVE
2391 def_bool y
2392 depends on MEMORY_HOTPLUG
2393
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002394config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002395 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002396 depends on NUMA
2397
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002398config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2399 def_bool y
2400 depends on X86_64 || X86_PAE
2401
Naoya Horiguchic177c812014-06-04 16:05:35 -07002402config ARCH_ENABLE_HUGEPAGE_MIGRATION
2403 def_bool y
2404 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2405
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002406config ARCH_ENABLE_THP_MIGRATION
2407 def_bool y
2408 depends on X86_64 && TRANSPARENT_HUGEPAGE
2409
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002410menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002411
2412config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002413 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002414 depends on X86_64 && HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002415
2416source "kernel/power/Kconfig"
2417
2418source "drivers/acpi/Kconfig"
2419
Feng Tangefafc8b2009-08-14 15:23:29 -04002420source "drivers/sfi/Kconfig"
2421
Andi Kleena6b68072008-01-30 13:32:49 +01002422config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002423 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002424 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002425
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002426menuconfig APM
2427 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002428 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002429 ---help---
2430 APM is a BIOS specification for saving power using several different
2431 techniques. This is mostly useful for battery powered laptops with
2432 APM compliant BIOSes. If you say Y here, the system time will be
2433 reset after a RESUME operation, the /proc/apm device will provide
2434 battery status information, and user-space programs will receive
2435 notification of APM "events" (e.g. battery status change).
2436
2437 If you select "Y" here, you can disable actual use of the APM
2438 BIOS by passing the "apm=off" option to the kernel at boot time.
2439
2440 Note that the APM support is almost completely disabled for
2441 machines with more than one CPU.
2442
2443 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002444 and more information, read <file:Documentation/power/apm-acpi.txt>
2445 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002446 <http://www.tldp.org/docs.html#howto>.
2447
2448 This driver does not spin down disk drives (see the hdparm(8)
2449 manpage ("man 8 hdparm") for that), and it doesn't turn off
2450 VESA-compliant "green" monitors.
2451
2452 This driver does not support the TI 4000M TravelMate and the ACER
2453 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2454 desktop machines also don't have compliant BIOSes, and this driver
2455 may cause those machines to panic during the boot phase.
2456
2457 Generally, if you don't have a battery in your machine, there isn't
2458 much point in using this driver and you should say N. If you get
2459 random kernel OOPSes or reboots that don't seem to be related to
2460 anything, try disabling/enabling this option (or disabling/enabling
2461 APM in your BIOS).
2462
2463 Some other things you should try when experiencing seemingly random,
2464 "weird" problems:
2465
2466 1) make sure that you have enough swap space and that it is
2467 enabled.
2468 2) pass the "no-hlt" option to the kernel
2469 3) switch on floating point emulation in the kernel and pass
2470 the "no387" option to the kernel
2471 4) pass the "floppy=nodma" option to the kernel
2472 5) pass the "mem=4M" option to the kernel (thereby disabling
2473 all but the first 4 MB of RAM)
2474 6) make sure that the CPU is not over clocked.
2475 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2476 8) disable the cache from your BIOS settings
2477 9) install a fan for the video card or exchange video RAM
2478 10) install a better fan for the CPU
2479 11) exchange RAM chips
2480 12) exchange the motherboard.
2481
2482 To compile this driver as a module, choose M here: the
2483 module will be called apm.
2484
2485if APM
2486
2487config APM_IGNORE_USER_SUSPEND
2488 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002489 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002490 This option will ignore USER SUSPEND requests. On machines with a
2491 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2492 series notebooks, it is necessary to say Y because of a BIOS bug.
2493
2494config APM_DO_ENABLE
2495 bool "Enable PM at boot time"
2496 ---help---
2497 Enable APM features at boot time. From page 36 of the APM BIOS
2498 specification: "When disabled, the APM BIOS does not automatically
2499 power manage devices, enter the Standby State, enter the Suspend
2500 State, or take power saving steps in response to CPU Idle calls."
2501 This driver will make CPU Idle calls when Linux is idle (unless this
2502 feature is turned off -- see "Do CPU IDLE calls", below). This
2503 should always save battery power, but more complicated APM features
2504 will be dependent on your BIOS implementation. You may need to turn
2505 this option off if your computer hangs at boot time when using APM
2506 support, or if it beeps continuously instead of suspending. Turn
2507 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2508 T400CDT. This is off by default since most machines do fine without
2509 this feature.
2510
2511config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002512 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002513 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002514 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002515 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2516 On some machines, this can activate improved power savings, such as
2517 a slowed CPU clock rate, when the machine is idle. These idle calls
2518 are made after the idle loop has run for some length of time (e.g.,
2519 333 mS). On some machines, this will cause a hang at boot time or
2520 whenever the CPU becomes idle. (On machines with more than one CPU,
2521 this option does nothing.)
2522
2523config APM_DISPLAY_BLANK
2524 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002525 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002526 Enable console blanking using the APM. Some laptops can use this to
2527 turn off the LCD backlight when the screen blanker of the Linux
2528 virtual console blanks the screen. Note that this is only used by
2529 the virtual console screen blanker, and won't turn off the backlight
2530 when using the X Window system. This also doesn't have anything to
2531 do with your VESA-compliant power-saving monitor. Further, this
2532 option doesn't work for all laptops -- it might not turn off your
2533 backlight at all, or it might print a lot of errors to the console,
2534 especially if you are using gpm.
2535
2536config APM_ALLOW_INTS
2537 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002538 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002539 Normally we disable external interrupts while we are making calls to
2540 the APM BIOS as a measure to lessen the effects of a badly behaving
2541 BIOS implementation. The BIOS should reenable interrupts if it
2542 needs to. Unfortunately, some BIOSes do not -- especially those in
2543 many of the newer IBM Thinkpads. If you experience hangs when you
2544 suspend, try setting this to Y. Otherwise, say N.
2545
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002546endif # APM
2547
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002548source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002549
2550source "drivers/cpuidle/Kconfig"
2551
Andy Henroid27471fd2008-10-09 11:45:22 -07002552source "drivers/idle/Kconfig"
2553
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002554endmenu
2555
2556
2557menu "Bus options (PCI etc.)"
2558
2559config PCI
Ingo Molnar1ac97012008-05-19 14:10:14 +02002560 bool "PCI support"
Adrian Bunk1c858082008-01-30 13:32:32 +01002561 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002562 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002563 Find out whether you have a PCI motherboard. PCI is the name of a
2564 bus system, i.e. the way the CPU talks to the other stuff inside
2565 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2566 VESA. If you have PCI, say Y, otherwise N.
2567
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002568choice
2569 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002570 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002571 default PCI_GOANY
2572 ---help---
2573 On PCI systems, the BIOS can be used to detect the PCI devices and
2574 determine their configuration. However, some old PCI motherboards
2575 have BIOS bugs and may crash if this is done. Also, some embedded
2576 PCI-based systems don't have any BIOS at all. Linux can also try to
2577 detect the PCI hardware directly without using the BIOS.
2578
2579 With this option, you can specify how Linux should detect the
2580 PCI devices. If you choose "BIOS", the BIOS will be used,
2581 if you choose "Direct", the BIOS won't be used, and if you
2582 choose "MMConfig", then PCI Express MMCONFIG will be used.
2583 If you choose "Any", the kernel will try MMCONFIG, then the
2584 direct access method and falls back to the BIOS if that doesn't
2585 work. If unsure, go with the default, which is "Any".
2586
2587config PCI_GOBIOS
2588 bool "BIOS"
2589
2590config PCI_GOMMCONFIG
2591 bool "MMConfig"
2592
2593config PCI_GODIRECT
2594 bool "Direct"
2595
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002596config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002597 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002598 depends on OLPC
2599
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002600config PCI_GOANY
2601 bool "Any"
2602
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002603endchoice
2604
2605config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002606 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002607 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002608
2609# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2610config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002611 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002612 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002613
2614config PCI_MMCONFIG
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002615 bool "Support mmconfig PCI config space access" if X86_64
2616 default y
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002617 depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002618 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002619
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002620config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002621 def_bool y
2622 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002623
Alex Nixonb5401a92010-03-18 16:31:34 -04002624config PCI_XEN
2625 def_bool y
2626 depends on PCI && XEN
2627 select SWIOTLB_XEN
2628
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002629config PCI_DOMAINS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002630 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002631 depends on PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002632
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002633config MMCONF_FAM10H
2634 def_bool y
2635 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002636
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002637config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002638 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002639 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002640 help
2641 Read the PCI windows out of the CNB20LE host bridge. This allows
2642 PCI hotplug to work on systems with the CNB20LE chipset which do
2643 not have ACPI.
2644
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002645 There's no public spec for this chipset, and this functionality
2646 is known to be incomplete.
2647
2648 You should say N unless you know you need this.
2649
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002650source "drivers/pci/Kconfig"
2651
William Breathitt Gray3a495512016-05-27 18:08:27 -04002652config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002653 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002654 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002655 Expose ISA bus device drivers and options available for selection and
2656 configuration. Enable this option if your target machine has an ISA
2657 bus. ISA is an older system, displaced by PCI and newer bus
2658 architectures -- if your target machine is modern, it probably does
2659 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002660
2661 If unsure, say N.
2662
David Rientjes1c00f012011-03-22 16:34:59 -07002663# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002664config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002665 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2666 default y
2667 help
2668 Enables ISA-style DMA support for devices requiring such controllers.
2669 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002670
Linus Torvalds51e68d02016-05-21 10:25:19 -07002671if X86_32
2672
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002673config ISA
2674 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002675 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002676 Find out whether you have ISA slots on your motherboard. ISA is the
2677 name of a bus system, i.e. the way the CPU talks to the other stuff
2678 inside your box. Other bus systems are PCI, EISA, MicroChannel
2679 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2680 newer boards don't support it. If you have ISA, say Y, otherwise N.
2681
2682config EISA
2683 bool "EISA support"
2684 depends on ISA
2685 ---help---
2686 The Extended Industry Standard Architecture (EISA) bus was
2687 developed as an open alternative to the IBM MicroChannel bus.
2688
2689 The EISA bus provided some of the features of the IBM MicroChannel
2690 bus while maintaining backward compatibility with cards made for
2691 the older ISA bus. The EISA bus saw limited use between 1988 and
2692 1995 when it was made obsolete by the PCI bus.
2693
2694 Say Y here if you are building a kernel for an EISA-based machine.
2695
2696 Otherwise, say N.
2697
2698source "drivers/eisa/Kconfig"
2699
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002700config SCx200
2701 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002702 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002703 This provides basic support for National Semiconductor's
2704 (now AMD's) Geode processors. The driver probes for the
2705 PCI-IDs of several on-chip devices, so its a good dependency
2706 for other scx200_* drivers.
2707
2708 If compiled as a module, the driver is named scx200.
2709
2710config SCx200HR_TIMER
2711 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002712 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002713 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002714 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002715 This driver provides a clocksource built upon the on-chip
2716 27MHz high-resolution timer. Its also a workaround for
2717 NSC Geode SC-1100's buggy TSC, which loses time when the
2718 processor goes idle (as is done by the scheduler). The
2719 other workaround is idle=poll boot option.
2720
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002721config OLPC
2722 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002723 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002724 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002725 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002726 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002727 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002728 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002729 Add support for detecting the unique features of the OLPC
2730 XO hardware.
2731
Daniel Drakea3128582011-06-25 17:34:10 +01002732config OLPC_XO1_PM
2733 bool "OLPC XO-1 Power Management"
Daniel Drake97c4cb72011-06-25 17:34:11 +01002734 depends on OLPC && MFD_CS5535 && PM_SLEEP
Daniel Drakea3128582011-06-25 17:34:10 +01002735 select MFD_CORE
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002736 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002737 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002738
Daniel Drakecfee9592011-06-25 17:34:17 +01002739config OLPC_XO1_RTC
2740 bool "OLPC XO-1 Real Time Clock"
2741 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2742 ---help---
2743 Add support for the XO-1 real time clock, which can be used as a
2744 programmable wakeup source.
2745
Daniel Drake7feda8e2011-06-25 17:34:12 +01002746config OLPC_XO1_SCI
2747 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002748 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002749 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002750 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002751 ---help---
2752 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002753 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002754 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002755 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002756 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002757 - AC adapter status updates
2758 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002759
Daniel Drakea0f30f52011-06-25 17:34:18 +01002760config OLPC_XO15_SCI
2761 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002762 depends on OLPC && ACPI
2763 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002764 ---help---
2765 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2766 - EC-driven system wakeups
2767 - AC adapter status updates
2768 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002769
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002770config ALIX
2771 bool "PCEngines ALIX System Support (LED setup)"
2772 select GPIOLIB
2773 ---help---
2774 This option enables system support for the PCEngines ALIX.
2775 At present this just sets up LEDs for GPIO control on
2776 ALIX2/3/6 boards. However, other system specific setup should
2777 get added here.
2778
2779 Note: You must still enable the drivers for GPIO and LED support
2780 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2781
2782 Note: You have to set alix.force=1 for boards with Award BIOS.
2783
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002784config NET5501
2785 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2786 select GPIOLIB
2787 ---help---
2788 This option enables system support for the Soekris Engineering net5501.
2789
Philip A. Prindeville31970592012-01-14 01:45:39 -07002790config GEOS
2791 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2792 select GPIOLIB
2793 depends on DMI
2794 ---help---
2795 This option enables system support for the Traverse Technologies GEOS.
2796
Vivien Didelot7d029122013-01-04 16:18:14 -05002797config TS5500
2798 bool "Technologic Systems TS-5500 platform support"
2799 depends on MELAN
2800 select CHECK_SIGNATURE
2801 select NEW_LEDS
2802 select LEDS_CLASS
2803 ---help---
2804 This option enables system support for the Technologic Systems TS-5500.
2805
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002806endif # X86_32
2807
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002808config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002809 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002810 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002811
2812source "drivers/pcmcia/Kconfig"
2813
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002814config RAPIDIO
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002815 tristate "RapidIO support"
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002816 depends on PCI
2817 default n
2818 help
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002819 If enabled this option will include drivers and the core
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002820 infrastructure code to support RapidIO interconnect devices.
2821
2822source "drivers/rapidio/Kconfig"
2823
David Herrmanne3263ab2013-08-02 14:05:22 +02002824config X86_SYSFB
2825 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2826 help
2827 Firmwares often provide initial graphics framebuffers so the BIOS,
2828 bootloader or kernel can show basic video-output during boot for
2829 user-guidance and debugging. Historically, x86 used the VESA BIOS
2830 Extensions and EFI-framebuffers for this, which are mostly limited
2831 to x86.
2832 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2833 framebuffers so the new generic system-framebuffer drivers can be
2834 used on x86. If the framebuffer is not compatible with the generic
2835 modes, it is adverticed as fallback platform framebuffer so legacy
2836 drivers like efifb, vesafb and uvesafb can pick it up.
2837 If this option is not selected, all system framebuffers are always
2838 marked as fallback platform framebuffers as usual.
2839
2840 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2841 not be able to pick up generic system framebuffers if this option
2842 is selected. You are highly encouraged to enable simplefb as
2843 replacement if you select this option. simplefb can correctly deal
2844 with generic system framebuffers. But you should still keep vesafb
2845 and others enabled as fallback if a system framebuffer is
2846 incompatible with simplefb.
2847
2848 If unsure, say Y.
2849
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002850endmenu
2851
2852
2853menu "Executable file formats / Emulations"
2854
2855source "fs/Kconfig.binfmt"
2856
2857config IA32_EMULATION
2858 bool "IA32 Emulation"
2859 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002860 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002861 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002862 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002863 select COMPAT_OLD_SIGACTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002864 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002865 Include code to run legacy 32-bit programs under a
2866 64-bit kernel. You should likely turn this on, unless you're
2867 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002868
2869config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002870 tristate "IA32 a.out support"
2871 depends on IA32_EMULATION
2872 ---help---
2873 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002874
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002875config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002876 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002877 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002878 ---help---
2879 Include code to run binaries for the x32 native 32-bit ABI
2880 for 64-bit processors. An x32 process gets access to the
2881 full 64-bit register file and wide data path while leaving
2882 pointers at 32 bits for smaller memory footprint.
2883
2884 You will need a recent binutils (2.22 or later) with
2885 elf32_x86_64 support enabled to compile a kernel with this
2886 option set.
2887
Ingo Molnar953fee12016-11-15 10:22:52 +01002888config COMPAT_32
2889 def_bool y
2890 depends on IA32_EMULATION || X86_32
2891 select HAVE_UID16
2892 select OLD_SIGSUSPEND3
2893
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002894config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002895 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002896 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002897
Jan Beulich3120e252012-09-10 12:41:45 +01002898if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002899config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002900 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002901
2902config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002903 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002904 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002905endif
David Howellsee009e4a02011-03-07 15:06:20 +00002906
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002907endmenu
2908
2909
Keith Packarde5beae12008-11-03 18:21:45 +01002910config HAVE_ATOMIC_IOMAP
2911 def_bool y
2912 depends on X86_32
2913
Alessandro Rubini4692d772012-04-04 19:39:58 +02002914config X86_DEV_DMA_OPS
2915 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002916 depends on X86_64 || STA2X11
Alessandro Rubini4692d772012-04-04 19:39:58 +02002917
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002918config X86_DMA_REMAP
2919 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002920 depends on STA2X11
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002921
Kirill A. Shutemove5855132017-06-06 14:31:20 +03002922config HAVE_GENERIC_GUP
2923 def_bool y
2924
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002925source "net/Kconfig"
2926
2927source "drivers/Kconfig"
2928
2929source "drivers/firmware/Kconfig"
2930
2931source "fs/Kconfig"
2932
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002933source "arch/x86/Kconfig.debug"
2934
2935source "security/Kconfig"
2936
2937source "crypto/Kconfig"
2938
Avi Kivityedf88412007-12-16 11:02:48 +02002939source "arch/x86/kvm/Kconfig"
2940
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002941source "lib/Kconfig"