blob: 5b4899de076f21df801062a672e9ab48801fca1b [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
31 select X86_DEV_DMA_OPS
Sam Ravnborg1032c0b2007-11-06 21:35:08 +010032
Ingo Molnard94e0682016-11-15 10:11:57 +010033#
34# Arch settings
35#
36# ( Note that options that are marked 'if X86_64' could in principle be
37# ported to 32-bit as well. )
38#
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +010039config X86
Harvey Harrison3c2362e2008-01-30 13:31:03 +010040 def_bool y
Ingo Molnarc763ea22016-11-15 10:26:39 +010041 #
42 # Note: keep this list sorted alphabetically
43 #
Ingo Molnar6471b822015-06-03 10:00:13 +020044 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
45 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
46 select ANON_INODES
47 select ARCH_CLOCKSOURCE_DATA
48 select ARCH_DISCARD_MEMBLOCK
Ingo Molnarc763ea22016-11-15 10:26:39 +010049 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
Laura Abbottfa5b6ec2017-01-10 13:35:40 -080050 select ARCH_HAS_DEBUG_VIRTUAL
Dan Williams21266be2015-11-19 18:19:29 -080051 select ARCH_HAS_DEVMEM_IS_ALLOWED
Ingo Molnar6471b822015-06-03 10:00:13 +020052 select ARCH_HAS_ELF_RANDOMIZE
Linus Torvalds72d93102014-09-13 11:14:53 -070053 select ARCH_HAS_FAST_MULTIPLIER
Daniel Micay6974f0c2017-07-12 14:36:10 -070054 select ARCH_HAS_FORTIFY_SOURCE
Riku Voipio957e3fa2014-12-12 16:57:44 -080055 select ARCH_HAS_GCOV_PROFILE_ALL
Dmitry Vyukov5c9a8752016-03-22 14:27:30 -070056 select ARCH_HAS_KCOV if X86_64
Mathieu Desnoyers10bcc802018-01-29 15:20:18 -050057 select ARCH_HAS_MEMBARRIER_SYNC_CORE
Ingo Molnarc763ea22016-11-15 10:26:39 +010058 select ARCH_HAS_PMEM_API if X86_64
Kees Cook39208aa2017-09-02 13:09:46 -070059 select ARCH_HAS_REFCOUNT
Dan Williams0aed55a2017-05-29 12:22:50 -070060 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Daniel Borkmannd2852a22017-02-21 16:09:33 +010061 select ARCH_HAS_SET_MEMORY
Ingo Molnar6471b822015-06-03 10:00:13 +020062 select ARCH_HAS_SG_CHAIN
Laura Abbottad21fc42017-02-06 16:31:57 -080063 select ARCH_HAS_STRICT_KERNEL_RWX
64 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050065 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Andrey Ryabininc6d30852016-01-20 15:00:55 -080066 select ARCH_HAS_UBSAN_SANITIZE_ALL
Oliver O'Halloran65f7d042017-06-28 11:32:31 +100067 select ARCH_HAS_ZONE_DEVICE if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020068 select ARCH_HAVE_NMI_SAFE_CMPXCHG
69 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040070 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080071 select ARCH_MIGHT_HAVE_PC_SERIO
Ingo Molnar6471b822015-06-03 10:00:13 +020072 select ARCH_SUPPORTS_ATOMIC_RMW
Ingo Molnar6471b822015-06-03 10:00:13 +020073 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
74 select ARCH_USE_BUILTIN_BSWAP
Ingo Molnar6471b822015-06-03 10:00:13 +020075 select ARCH_USE_QUEUED_RWLOCKS
76 select ARCH_USE_QUEUED_SPINLOCKS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -070077 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Ingo Molnarc763ea22016-11-15 10:26:39 +010078 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Huang Ying38d8b4e2017-07-06 15:37:18 -070079 select ARCH_WANTS_THP_SWAP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020080 select BUILDTIME_EXTABLE_SORT
81 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +020082 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
83 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +020084 select DCACHE_WORD_ACCESS
Christoph Hellwigfec777c2018-03-19 11:38:15 +010085 select DMA_DIRECT_OPS
Linus Torvalds45471cd2015-06-24 19:52:06 -070086 select EDAC_ATOMIC_SCRUB
87 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +020088 select GENERIC_CLOCKEVENTS
89 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
90 select GENERIC_CLOCKEVENTS_MIN_ADJUST
91 select GENERIC_CMOS_UPDATE
92 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +010093 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +020094 select GENERIC_EARLY_IOREMAP
95 select GENERIC_FIND_FIRST_BIT
96 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +020097 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +020098 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +020099 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200100 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200101 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200102 select GENERIC_IRQ_SHOW
103 select GENERIC_PENDING_IRQ if SMP
104 select GENERIC_SMP_IDLE_THREAD
105 select GENERIC_STRNCPY_FROM_USER
106 select GENERIC_STRNLEN_USER
107 select GENERIC_TIME_VSYSCALL
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200108 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200109 select HAVE_ACPI_APEI if ACPI
110 select HAVE_ACPI_APEI_NMI if ACPI
111 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200112 select HAVE_ARCH_AUDITSYSCALL
113 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
114 select HAVE_ARCH_JUMP_LABEL
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800115 select HAVE_ARCH_KASAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200116 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800117 select HAVE_ARCH_MMAP_RND_BITS if MMU
118 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300119 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ingo Molnar6471b822015-06-03 10:00:13 +0200120 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700121 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Ingo Molnar6471b822015-06-03 10:00:13 +0200122 select HAVE_ARCH_TRACEHOOK
123 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Matthew Wilcoxa00cc7d2017-02-24 14:57:02 -0800124 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
Andy Lutomirskie37e43a2016-08-11 02:35:23 -0700125 select HAVE_ARCH_VMAP_STACK if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100126 select HAVE_ARCH_WITHIN_STACK_FRAMES
Ingo Molnar6471b822015-06-03 10:00:13 +0200127 select HAVE_CC_STACKPROTECTOR
128 select HAVE_CMPXCHG_DOUBLE
129 select HAVE_CMPXCHG_LOCAL
130 select HAVE_CONTEXT_TRACKING if X86_64
Josh Triplettc1bd55f2015-06-30 15:00:00 -0700131 select HAVE_COPY_THREAD_TLS
Ingo Molnar6471b822015-06-03 10:00:13 +0200132 select HAVE_C_RECORDMCOUNT
133 select HAVE_DEBUG_KMEMLEAK
134 select HAVE_DEBUG_STACKOVERFLOW
135 select HAVE_DMA_API_DEBUG
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700136 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400137 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900138 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Ingo Molnarc763ea22016-11-15 10:26:39 +0100139 select HAVE_EBPF_JIT if X86_64
Johannes Berg58340a02008-07-25 01:45:33 -0700140 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Jiri Slaby5f56a5d2016-05-20 17:00:16 -0700141 select HAVE_EXIT_THREAD
Steven Rostedt (VMware)644e0e82017-03-23 10:33:52 -0400142 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
Ingo Molnar6471b822015-06-03 10:00:13 +0200143 select HAVE_FTRACE_MCOUNT_RECORD
Ingo Molnar6471b822015-06-03 10:00:13 +0200144 select HAVE_FUNCTION_GRAPH_TRACER
145 select HAVE_FUNCTION_TRACER
Emese Revfy6b90bd42016-05-24 00:09:38 +0200146 select HAVE_GCC_PLUGINS
K.Prasad0067f122009-06-01 23:43:57 +0530147 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200148 select HAVE_IDE
149 select HAVE_IOREMAP_PROT
150 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
151 select HAVE_IRQ_TIME_ACCOUNTING
152 select HAVE_KERNEL_BZIP2
153 select HAVE_KERNEL_GZIP
154 select HAVE_KERNEL_LZ4
155 select HAVE_KERNEL_LZMA
156 select HAVE_KERNEL_LZO
157 select HAVE_KERNEL_XZ
158 select HAVE_KPROBES
159 select HAVE_KPROBES_ON_FTRACE
Masami Hiramatsu540adea2018-01-13 02:55:03 +0900160 select HAVE_FUNCTION_ERROR_INJECTION
Ingo Molnar6471b822015-06-03 10:00:13 +0200161 select HAVE_KRETPROBES
162 select HAVE_KVM
163 select HAVE_LIVEPATCH if X86_64
164 select HAVE_MEMBLOCK
165 select HAVE_MEMBLOCK_NODE_MAP
Frederic Weisbecker01027522010-04-11 18:55:56 +0200166 select HAVE_MIXED_BREAKPOINTS_REGS
Josh Poimboeufee9f8fc2017-07-24 18:36:57 -0500167 select HAVE_MOD_ARCH_SPECIFIC
Petr Mladek42a0bb32016-05-20 17:00:33 -0700168 select HAVE_NMI
Ingo Molnar6471b822015-06-03 10:00:13 +0200169 select HAVE_OPROFILE
170 select HAVE_OPTPROBES
171 select HAVE_PCSPKR_PLATFORM
172 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200173 select HAVE_PERF_EVENTS_NMI
Nicholas Piggin92e5aae2017-08-18 15:15:51 -0700174 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
Jiri Olsac5e63192012-08-07 15:20:36 +0200175 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200176 select HAVE_PERF_USER_STACK_DUMP
Vitaly Kuznetsov9e52fc22017-08-28 10:22:51 +0200177 select HAVE_RCU_TABLE_FREE
Ingo Molnar6471b822015-06-03 10:00:13 +0200178 select HAVE_REGS_AND_STACK_ACCESS_API
Josh Poimboeuf11af8472017-10-13 15:02:00 -0500179 select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
Ingo Molnarc763ea22016-11-15 10:26:39 +0100180 select HAVE_STACK_VALIDATION if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200181 select HAVE_SYSCALL_TRACEPOINTS
Ingo Molnar6471b822015-06-03 10:00:13 +0200182 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300183 select HAVE_USER_RETURN_NOTIFIER
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100184 select IRQ_FORCED_THREADING
Thomas Gleixnerdf65c1b2017-03-16 22:50:07 +0100185 select PCI_LOCKLESS_CONFIG
Ingo Molnar6471b822015-06-03 10:00:13 +0200186 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500187 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200188 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200189 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500190 select SRCU
Ingo Molnar6471b822015-06-03 10:00:13 +0200191 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700192 select THREAD_INFO_IN_TASK
Ingo Molnar6471b822015-06-03 10:00:13 +0200193 select USER_STACKTRACE_SUPPORT
194 select VIRT_TO_BUS
Ingo Molnar6471b822015-06-03 10:00:13 +0200195 select X86_FEATURE_NAMES if PROC_FS
Balbir Singh7d8330a2008-02-10 12:46:28 +0530196
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200197config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100198 def_bool y
199 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200200
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700201config OUTPUT_FORMAT
202 string
203 default "elf32-i386" if X86_32
204 default "elf64-x86-64" if X86_64
205
Sam Ravnborg73531902008-05-25 23:03:18 +0200206config ARCH_DEFCONFIG
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200207 string
Sam Ravnborg73531902008-05-25 23:03:18 +0200208 default "arch/x86/configs/i386_defconfig" if X86_32
209 default "arch/x86/configs/x86_64_defconfig" if X86_64
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200210
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100211config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100212 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100213
214config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100215 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100216
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100217config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100218 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100219
Daniel Cashman9e08f572016-01-14 15:20:06 -0800220config ARCH_MMAP_RND_BITS_MIN
221 default 28 if 64BIT
222 default 8
223
224config ARCH_MMAP_RND_BITS_MAX
225 default 32 if 64BIT
226 default 16
227
228config ARCH_MMAP_RND_COMPAT_BITS_MIN
229 default 8
230
231config ARCH_MMAP_RND_COMPAT_BITS_MAX
232 default 16
233
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100234config SBUS
235 bool
236
FUJITA Tomonori3bc4e452010-03-10 15:23:22 -0800237config NEED_DMA_MAP_STATE
Jan Beulich3120e252012-09-10 12:41:45 +0100238 def_bool y
Konrad Rzeszutek Wilka6dfa122015-04-17 15:04:48 -0400239 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
FUJITA Tomonori3bc4e452010-03-10 15:23:22 -0800240
FUJITA Tomonori18e98302010-05-26 14:44:32 -0700241config NEED_SG_DMA_LENGTH
Andrew Morton4a14d842010-05-26 14:44:33 -0700242 def_bool y
FUJITA Tomonori18e98302010-05-26 14:44:32 -0700243
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100244config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100245 def_bool y
246 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100247
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100248config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100249 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100250 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000251 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
252
253config GENERIC_BUG_RELATIVE_POINTERS
254 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100255
256config GENERIC_HWEIGHT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100257 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100258
259config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100260 def_bool y
261 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100262
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100263config RWSEM_XCHGADD_ALGORITHM
Jan Beulich3120e252012-09-10 12:41:45 +0100264 def_bool y
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100265
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100266config GENERIC_CALIBRATE_DELAY
267 def_bool y
268
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800269config ARCH_HAS_CPU_RELAX
270 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100271
Pekka Enberg1b27d052008-04-28 02:12:22 -0700272config ARCH_HAS_CACHE_LINE_SIZE
273 def_bool y
274
Mike Travisdd5af902008-01-30 13:33:32 +0100275config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900276 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100277
Tejun Heo08fc4582009-08-14 15:00:49 +0900278config NEED_PER_CPU_EMBED_FIRST_CHUNK
279 def_bool y
280
281config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900282 def_bool y
283
Johannes Berg801e4062007-12-08 02:12:39 +0100284config ARCH_HIBERNATION_POSSIBLE
285 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100286
Johannes Bergf4cb5702007-12-08 02:14:00 +0100287config ARCH_SUSPEND_POSSIBLE
288 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100289
Steve Cappercfe28c52013-04-29 14:29:48 +0100290config ARCH_WANT_HUGE_PMD_SHARE
291 def_bool y
292
Steve Capper53313b22013-04-30 08:03:42 +0100293config ARCH_WANT_GENERAL_HUGETLB
294 def_bool y
295
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100296config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000297 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100298
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100299config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000300 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100301
Ingo Molnar765c68b2008-04-09 11:03:37 +0200302config ARCH_SUPPORTS_OPTIMIZED_INLINING
303 def_bool y
304
Akinobu Mita6a11f752009-03-31 15:23:17 -0700305config ARCH_SUPPORTS_DEBUG_PAGEALLOC
306 def_bool y
307
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300308config KASAN_SHADOW_OFFSET
309 hex
310 depends on KASAN
311 default 0xdffffc0000000000
312
Shane Wang69575d32009-09-01 18:25:07 -0700313config HAVE_INTEL_TXT
314 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700315 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700316
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100317config X86_32_SMP
318 def_bool y
319 depends on X86_32 && SMP
320
321config X86_64_SMP
322 def_bool y
323 depends on X86_64 && SMP
324
Tejun Heoccbeed32009-02-09 22:17:40 +0900325config X86_32_LAZY_GS
326 def_bool y
Kees Cook2bc2f682018-02-06 15:37:41 -0800327 depends on X86_32 && CC_STACKPROTECTOR_NONE
Tejun Heoccbeed32009-02-09 22:17:40 +0900328
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530329config ARCH_SUPPORTS_UPROBES
330 def_bool y
331
Rob Herringd20642f2014-04-18 17:19:54 -0500332config FIX_EARLYCON_MEM
333 def_bool y
334
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700335config PGTABLE_LEVELS
336 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300337 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700338 default 4 if X86_64
339 default 3 if X86_PAE
340 default 2
341
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100342source "init/Kconfig"
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700343source "kernel/Kconfig.freezer"
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100344
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100345menu "Processor type and features"
346
Randy Dunlap5ee71532012-01-16 11:57:18 -0800347config ZONE_DMA
348 bool "DMA memory allocation support" if EXPERT
349 default y
350 help
351 DMA memory allocation support allows devices with less than 32-bit
352 addressing to allocate within the first 16MB of address space.
353 Disable if no such devices will be used.
354
355 If unsure, say Y.
356
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100357config SMP
358 bool "Symmetric multi-processing support"
359 ---help---
360 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800361 a system with only one CPU, say N. If you have a system with more
362 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100363
Robert Graffham4a474152014-01-23 15:55:29 -0800364 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100365 machines, but will use only one CPU of a multiprocessor machine. If
366 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800367 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100368 will run faster if you say N here.
369
370 Note that if you say Y here and choose architecture "586" or
371 "Pentium" under "Processor family", the kernel will not work on 486
372 architectures. Similarly, multiprocessor kernels for the "PPro"
373 architecture may not work on all Pentium based boards.
374
375 People using multiprocessor machines who say Y here should also say
376 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
377 Management" code will be disabled if you say Y here.
378
Paul Bolle395cf962011-08-15 02:02:26 +0200379 See also <file:Documentation/x86/i386/IO-APIC.txt>,
Benjamin Petersonc9525a32017-05-20 17:20:16 -0700380 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100381 <http://www.tldp.org/docs.html#howto>.
382
383 If you don't know what to do here, say N.
384
Josh Triplett9def39be2013-10-30 08:09:45 -0700385config X86_FEATURE_NAMES
386 bool "Processor feature human-readable names" if EMBEDDED
387 default y
388 ---help---
389 This option compiles in a table of x86 feature bits and corresponding
390 names. This is required to support /proc/cpuinfo and a few kernel
391 messages. You can disable this to save space, at the expense of
392 making those few kernel messages show numeric feature bits instead.
393
394 If in doubt, say Y.
395
Borislav Petkov6e1315f2015-12-07 10:39:42 +0100396config X86_FAST_FEATURE_TESTS
397 bool "Fast CPU feature tests" if EMBEDDED
398 default y
399 ---help---
400 Some fast-paths in the kernel depend on the capabilities of the CPU.
401 Say Y here for the kernel to patch in the appropriate code at runtime
402 based on the capabilities of the CPU. The infrastructure for patching
403 code at runtime takes up some additional space; space-constrained
404 embedded systems may wish to say N here to produce smaller, slightly
405 slower code.
406
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800407config X86_X2APIC
408 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200409 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800410 ---help---
411 This enables x2apic support on CPUs that have this feature.
412
413 This allows 32-bit apic IDs (so it can support very large systems),
414 and accesses the local apic via MSRs not via mmio.
415
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800416 If you don't know what to do here, say N.
417
Yinghai Lu6695c852008-06-19 12:13:09 -0700418config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700419 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000420 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200421 depends on X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100422 ---help---
Yinghai Lu6695c852008-06-19 12:13:09 -0700423 For old smp systems that do not have proper acpi support. Newer systems
424 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700425
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000426config GOLDFISH
427 def_bool y
428 depends on X86_GOLDFISH
429
David Woodhouse76b04382018-01-11 21:46:25 +0000430config RETPOLINE
431 bool "Avoid speculative indirect branches in kernel"
432 default y
Peter Zijlstrad5028ba2018-02-06 09:46:13 +0100433 select STACK_VALIDATION if HAVE_STACK_VALIDATION
David Woodhouse76b04382018-01-11 21:46:25 +0000434 help
435 Compile kernel with the retpoline compiler options to guard against
436 kernel-to-user data leaks by avoiding speculative indirect
437 branches. Requires a compiler with -mindirect-branch=thunk-extern
438 support for full protection. The kernel may run slower.
439
440 Without compiler support, at least indirect branches in assembler
441 code are eliminated. Since this includes the syscall entry path,
442 it is not entirely pointless.
443
Vikas Shivappaf01d7d512017-07-25 14:14:22 -0700444config INTEL_RDT
445 bool "Intel Resource Director Technology support"
Fenghua Yu78e99b42016-10-22 06:19:53 -0700446 default n
447 depends on X86 && CPU_SUP_INTEL
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100448 select KERNFS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700449 help
Vikas Shivappaf01d7d512017-07-25 14:14:22 -0700450 Select to enable resource allocation and monitoring which are
451 sub-features of Intel Resource Director Technology(RDT). More
452 information about RDT can be found in the Intel x86
453 Architecture Software Developer Manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700454
455 Say N if unsure.
456
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800457if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800458config X86_BIGSMP
459 bool "Support for big SMP systems with more than 8 CPUs"
460 depends on SMP
461 ---help---
462 This option is needed for the systems that have more than 8 CPUs
463
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800464config X86_EXTENDED_PLATFORM
465 bool "Support for extended (non-PC) x86 platforms"
466 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100467 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100468 If you disable this option then the kernel will only support
469 standard PC platforms. (which covers the vast majority of
470 systems out there.)
471
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800472 If you enable this option then you'll be able to select support
473 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100474 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800475 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800476 RDC R-321x SoC
477 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200478 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200479 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100480
481 If you have one of these systems, or if you want to build a
482 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800483endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100484
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800485if X86_64
486config X86_EXTENDED_PLATFORM
487 bool "Support for extended (non-PC) x86 platforms"
488 default y
489 ---help---
490 If you disable this option then the kernel will only support
491 standard PC platforms. (which covers the vast majority of
492 systems out there.)
493
494 If you enable this option then you'll be able to select support
495 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800496 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800497 ScaleMP vSMP
498 SGI Ultraviolet
499
500 If you have one of these systems, or if you want to build a
501 generic distribution kernel, say Y here - otherwise say N.
502endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800503# This is an alphabetically sorted list of 64 bit extended platforms
504# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800505config X86_NUMACHIP
506 bool "Numascale NumaChip"
507 depends on X86_64
508 depends on X86_EXTENDED_PLATFORM
509 depends on NUMA
510 depends on SMP
511 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700512 depends on PCI_MMCONFIG
Steffen Persvold44b111b52011-12-06 00:07:26 +0800513 ---help---
514 Adds support for Numascale NumaChip large-SMP systems. Needed to
515 enable more than ~168 cores.
516 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100517
Ingo Molnar6a485652009-01-27 18:29:13 +0100518config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800519 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100520 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100521 select PARAVIRT
522 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800523 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300524 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100525 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100526 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
527 supposed to run on these EM64T-based machines. Only choose this option
528 if you have one of these machines.
529
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800530config X86_UV
531 bool "SGI Ultraviolet"
532 depends on X86_64
533 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500534 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800535 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700536 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200537 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800538 ---help---
539 This option is needed in order to support SGI Ultraviolet systems.
540 If you don't have one of these, you should say N here.
541
542# Following is an alphabetically sorted list of 32 bit extended platforms
543# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100544
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000545config X86_GOLDFISH
546 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100547 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000548 ---help---
549 Enable support for the Goldfish virtual platform used primarily
550 for Android development. Unless you are building for the Android
551 Goldfish emulator say N here.
552
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800553config X86_INTEL_CE
554 bool "CE4100 TV platform"
555 depends on PCI
556 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800557 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800558 depends on X86_32
559 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800560 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100561 select OF
562 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800563 ---help---
564 Select for the Intel CE media processor (CE4100) SOC.
565 This option compiles in support for the CE4100 SOC for settop
566 boxes and media devices.
567
David Cohen4cb9b002013-12-16 17:37:26 -0800568config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100569 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100570 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800571 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000572 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200573 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000574 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000575 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800576 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000577 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000578 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000579 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000580 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000581 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800582 Select to build a kernel capable of supporting Intel MID (Mobile
583 Internet Device) platform systems which do not have the PCI legacy
584 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000585
David Cohen4cb9b002013-12-16 17:37:26 -0800586 Intel MID platforms are based on an Intel processor and chipset which
587 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100588
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000589config X86_INTEL_QUARK
590 bool "Intel Quark platform support"
591 depends on X86_32
592 depends on X86_EXTENDED_PLATFORM
593 depends on X86_PLATFORM_DEVICES
594 depends on X86_TSC
595 depends on PCI
596 depends on PCI_GOANY
597 depends on X86_IO_APIC
598 select IOSF_MBI
599 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200600 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000601 ---help---
602 Select to include support for Quark X1000 SoC.
603 Say Y here if you have a Quark based system such as the Arduino
604 compatible Intel Galileo.
605
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000606config X86_INTEL_LPSS
607 bool "Intel Low Power Subsystem Support"
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100608 depends on X86 && ACPI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000609 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300610 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100611 select IOSF_MBI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000612 ---help---
613 Select to build support for Intel Low Power Subsystem such as
614 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300615 things like clock tree (common clock framework) and pincontrol
616 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000617
Ken Xue92082a82015-02-06 08:27:51 +0800618config X86_AMD_PLATFORM_DEVICE
619 bool "AMD ACPI2Platform devices support"
620 depends on ACPI
621 select COMMON_CLK
622 select PINCTRL
623 ---help---
624 Select to interpret AMD specific ACPI device to platform device
625 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
626 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
627 implemented under PINCTRL subsystem.
628
David E. Boxced3ce72014-09-17 22:13:50 -0700629config IOSF_MBI
630 tristate "Intel SoC IOSF Sideband support for SoC platforms"
631 depends on PCI
632 ---help---
633 This option enables sideband register access support for Intel SoC
634 platforms. On these platforms the IOSF sideband is used in lieu of
635 MSR's for some register accesses, mostly but not limited to thermal
636 and power. Drivers may query the availability of this device to
637 determine if they need the sideband in order to work on these
638 platforms. The sideband is available on the following SoC products.
639 This list is not meant to be exclusive.
640 - BayTrail
641 - Braswell
642 - Quark
643
644 You should say Y if you are running a kernel on one of these SoC's.
645
David E. Boxed2226b2014-09-17 22:13:51 -0700646config IOSF_MBI_DEBUG
647 bool "Enable IOSF sideband access through debugfs"
648 depends on IOSF_MBI && DEBUG_FS
649 ---help---
650 Select this option to expose the IOSF sideband access registers (MCR,
651 MDR, MCRX) through debugfs to write and read register information from
652 different units on the SoC. This is most useful for obtaining device
653 state information for debug and analysis. As this is a general access
654 mechanism, users of this option would have specific knowledge of the
655 device they want to access.
656
657 If you don't require the option or are in doubt, say N.
658
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800659config X86_RDC321X
660 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100661 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800662 depends on X86_EXTENDED_PLATFORM
663 select M486
664 select X86_REBOOTFIXUPS
665 ---help---
666 This option is needed for RDC R-321x system-on-chip, also known
667 as R-8610-(G).
668 If you don't have one of these chips, you should say N here.
669
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100670config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100671 bool "Support non-standard 32-bit SMP architectures"
672 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800673 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100674 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800675 This option compiles in the bigsmp and STA2X11 default
676 subarchitectures. It is intended for a generic binary
677 kernel. If you select them all, kernel will probe it one by
678 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700679
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800680# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700681
Linus Torvaldsd949f362009-09-26 09:35:07 -0700682config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100683 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700684 # MCE code calls memory_failure():
685 depends on X86_MCE
686 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700687 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
688 depends on X86_64 || !SPARSEMEM
689 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700690
Alessandro Rubini83125a32012-04-04 19:40:21 +0200691config STA2X11
692 bool "STA2X11 Companion Chip Support"
693 depends on X86_32_NON_STANDARD && PCI
Christoph Hellwigb6e05472018-03-19 11:38:24 +0100694 select ARCH_HAS_PHYS_TO_DMA
Alessandro Rubini83125a32012-04-04 19:40:21 +0200695 select X86_DEV_DMA_OPS
696 select X86_DMA_REMAP
697 select SWIOTLB
698 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200699 select GPIOLIB
Alessandro Rubini83125a32012-04-04 19:40:21 +0200700 default n
701 ---help---
702 This adds support for boards based on the STA2X11 IO-Hub,
703 a.k.a. "ConneXt". The chip is used in place of the standard
704 PC chipset, so all "standard" peripherals are missing. If this
705 option is selected the kernel will still be able to boot on
706 standard PC machines.
707
Shérab82148d12010-09-25 06:06:57 +0200708config X86_32_IRIS
709 tristate "Eurobraille/Iris poweroff module"
710 depends on X86_32
711 ---help---
712 The Iris machines from EuroBraille do not have APM or ACPI support
713 to shut themselves down properly. A special I/O sequence is
714 needed to do so, which is what this module does at
715 kernel shutdown.
716
717 This is only for Iris machines from EuroBraille.
718
719 If unused, say N.
720
Ingo Molnarae1e9132008-11-11 09:05:16 +0100721config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100722 def_bool y
723 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800724 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100725 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100726 Calculate simpler /proc/<PID>/wchan values. If this option
727 is disabled then wchan values will recurse back to the
728 caller function. This provides more accurate wchan values,
729 at the expense of slightly more scheduling overhead.
730
731 If in doubt, say "Y".
732
Borislav Petkov6276a072013-03-04 21:20:21 +0100733menuconfig HYPERVISOR_GUEST
734 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100735 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100736 Say Y here to enable options for running Linux under various hyper-
737 visors. This option enables basic hypervisor detection and platform
738 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100739
Borislav Petkov6276a072013-03-04 21:20:21 +0100740 If you say N, all options in this submenu will be skipped and
741 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100742
Borislav Petkov6276a072013-03-04 21:20:21 +0100743if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100744
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100745config PARAVIRT
746 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100747 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100748 This changes the kernel so it can modify itself when it is run
749 under a hypervisor, potentially improving performance significantly
750 over full virtualization. However, when run without a hypervisor
751 the kernel is theoretically slower and slightly larger.
752
Borislav Petkov6276a072013-03-04 21:20:21 +0100753config PARAVIRT_DEBUG
754 bool "paravirt-ops debugging"
755 depends on PARAVIRT && DEBUG_KERNEL
756 ---help---
757 Enable to debug paravirt_ops internals. Specifically, BUG if
758 a paravirt_op is missing when it is called.
759
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700760config PARAVIRT_SPINLOCKS
761 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700762 depends on PARAVIRT && SMP
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700763 ---help---
764 Paravirtualized spinlocks allow a pvops backend to replace the
765 spinlock implementation with something virtualization-friendly
766 (for example, block the virtual CPU rather than spinning).
767
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530768 It has a minimal impact on native kernels and gives a nice performance
769 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700770
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530771 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700772
Waiman Long45e898b2015-11-09 19:09:25 -0500773config QUEUED_LOCK_STAT
774 bool "Paravirt queued spinlock statistics"
Peter Zijlstracfd89832016-05-18 20:43:02 +0200775 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
Waiman Long45e898b2015-11-09 19:09:25 -0500776 ---help---
777 Enable the collection of statistical data on the slowpath
778 behavior of paravirtualized queued spinlocks and report
779 them on debugfs.
780
Borislav Petkov6276a072013-03-04 21:20:21 +0100781source "arch/x86/xen/Kconfig"
782
783config KVM_GUEST
784 bool "KVM Guest support (including kvmclock)"
785 depends on PARAVIRT
786 select PARAVIRT_CLOCK
787 default y
788 ---help---
789 This option enables various optimizations for running under the KVM
790 hypervisor. It includes a paravirtualized clock, so that instead
791 of relying on a PIT (or probably other) emulation by the
792 underlying device model, the host provides the guest with
793 timing infrastructure such as time of day, and system time
794
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530795config KVM_DEBUG_FS
796 bool "Enable debug information for KVM Guests in debugfs"
797 depends on KVM_GUEST && DEBUG_FS
798 default n
799 ---help---
800 This option enables collection of various statistics for KVM guest.
801 Statistics are displayed in debugfs filesystem. Enabling this option
802 may incur significant overhead.
803
Borislav Petkov6276a072013-03-04 21:20:21 +0100804config PARAVIRT_TIME_ACCOUNTING
805 bool "Paravirtual steal time accounting"
806 depends on PARAVIRT
807 default n
808 ---help---
809 Select this option to enable fine granularity task steal time
810 accounting. Time spent executing other tasks in parallel with
811 the current vCPU is discounted from the vCPU power. To account for
812 that, there can be a small performance impact.
813
814 If in doubt, say N here.
815
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200816config PARAVIRT_CLOCK
817 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200818
Jan Kiszka4a362602017-11-27 09:11:46 +0100819config JAILHOUSE_GUEST
820 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100821 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100822 select X86_PM_TIMER
Jan Kiszka4a362602017-11-27 09:11:46 +0100823 ---help---
824 This option allows to run Linux as guest in a Jailhouse non-root
825 cell. You can leave this option disabled if you only want to start
826 Jailhouse and run Linux afterwards in the root cell.
827
Borislav Petkov6276a072013-03-04 21:20:21 +0100828endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400829
Yinghai Lu08677212010-02-10 01:20:20 -0800830config NO_BOOTMEM
Yinghai Lu774ea0b2010-08-25 13:39:18 -0700831 def_bool y
Yinghai Lu08677212010-02-10 01:20:20 -0800832
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100833source "arch/x86/Kconfig.cpu"
834
835config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100836 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100837 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100838 ---help---
839 Use the IA-PC HPET (High Precision Event Timer) to manage
840 time in preference to the PIT and RTC, if a HPET is
841 present.
842 HPET is the next generation timer replacing legacy 8254s.
843 The HPET provides a stable time base on SMP
844 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200845 as it is off-chip. The interface used is documented
846 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100847
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100848 You can safely choose Y here. However, HPET will only be
849 activated if the platform and the BIOS support this feature.
850 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100851
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100852 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100853
854config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100855 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800856 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100857
Jacob Panbb24c472009-09-02 07:37:17 -0700858config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000859 def_bool y if X86_INTEL_MID
860 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100861 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000862 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700863 help
864 APB timer is the replacement for 8254, HPET on X86 MID platforms.
865 The APBT provides a stable time base on SMP
866 systems, unlike the TSC, but it is more expensive to access,
867 as it is off-chip. APB timers are always running regardless of CPU
868 C states, they are used as per CPU clockevent device when possible.
869
David Rientjes6a108a12011-01-20 14:44:16 -0800870# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100871# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700872config DMI
873 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800874 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800875 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100876 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700877 Enabled scanning of DMI to identify machine quirks. Say Y
878 here unless you have verified that your setup is not
879 affected by entries in the DMI blacklist. Required by PNP
880 BIOS code.
881
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100882config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700883 bool "Old AMD GART IOMMU support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100884 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200885 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100886 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200887 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
888 GART based hardware IOMMUs.
889
890 The GART supports full DMA access for devices with 32-bit access
891 limitations, on systems with more than 3 GB. This is usually needed
892 for USB, sound, many IDE/SATA chipsets and some other devices.
893
894 Newer systems typically have a modern AMD IOMMU, supported via
895 the CONFIG_AMD_IOMMU=y config option.
896
897 In normal configurations this driver is only active when needed:
898 there's more than 3 GB of memory and the system contains a
899 32-bit limited device.
900
901 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100902
903config CALGARY_IOMMU
904 bool "IBM Calgary IOMMU support"
905 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700906 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100907 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100908 Support for hardware IOMMUs in IBM's xSeries x366 and x460
909 systems. Needed to run systems with more than 3GB of memory
910 properly with 32-bit PCI devices that do not support DAC
911 (Double Address Cycle). Calgary also supports bus level
912 isolation, where all DMAs pass through the IOMMU. This
913 prevents them from going anywhere except their intended
914 destination. This catches hard-to-find kernel bugs and
915 mis-behaving drivers and devices that do not use the DMA-API
916 properly to set up their DMA buffers. The IOMMU can be
917 turned off at boot time with the iommu=off parameter.
918 Normally the kernel will make the right choice by itself.
919 If unsure, say Y.
920
921config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100922 def_bool y
923 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100924 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100925 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100926 Should Calgary be enabled by default? if you choose 'y', Calgary
927 will be used (if it exists). If you choose 'n', Calgary will not be
928 used even if it exists. If you choose 'n' and would like to use
929 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
930 If unsure, say Y.
931
932# need this always selected by IOMMU for the VIA workaround
933config SWIOTLB
Joerg Roedela1afd012008-11-18 12:44:21 +0100934 def_bool y if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100935 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100936 Support for software bounce buffers used on x86-64 systems
Joe Millenbach4454d322012-09-02 17:38:20 -0700937 which don't have a hardware IOMMU. Using this PCI devices
938 which can only access 32-bits of memory can be used on systems
939 with more than 3 GB of memory.
940 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100941
FUJITA Tomonoria8522502008-04-29 00:59:36 -0700942config IOMMU_HELPER
Jan Beulich3120e252012-09-10 12:41:45 +0100943 def_bool y
944 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
Linus Torvaldsd25e26b2008-08-25 14:15:38 -0700945
Mike Travis1184dc22008-05-12 21:21:12 +0200946config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200947 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700948 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800949 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100950 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200951 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200952 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100953
Ingo Molnaraec64872018-02-10 12:36:29 +0100954#
955# The maximum number of CPUs supported:
956#
957# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
958# and which can be configured interactively in the
959# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
960#
961# The ranges are different on 32-bit and 64-bit kernels, depending on
962# hardware capabilities and scalability features of the kernel.
963#
964# ( If MAXSMP is enabled we just use the highest possible value and disable
965# interactive configuration. )
966#
967
968config NR_CPUS_RANGE_BEGIN
969 int
970 default NR_CPUS_RANGE_END if MAXSMP
971 default 1 if !SMP
972 default 2
973
974config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800975 int
976 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100977 default 64 if SMP && X86_BIGSMP
978 default 8 if SMP && !X86_BIGSMP
979 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800980
Ingo Molnaraec64872018-02-10 12:36:29 +0100981config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800982 int
983 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100984 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
985 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
986 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800987
Ingo Molnaraec64872018-02-10 12:36:29 +0100988config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800989 int
990 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100991 default 32 if X86_BIGSMP
992 default 8 if SMP
993 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800994
Ingo Molnaraec64872018-02-10 12:36:29 +0100995config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800996 int
997 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100998 default 8192 if MAXSMP
999 default 64 if SMP
1000 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -08001001
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001002config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -08001003 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +01001004 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
1005 default NR_CPUS_DEFAULT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001006 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001007 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -05001008 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +03001009 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001010 minimum value which makes sense is 2.
1011
Ingo Molnaraec64872018-02-10 12:36:29 +01001012 This is purely to save memory: each supported CPU adds about 8KB
1013 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001014
1015config SCHED_SMT
1016 bool "SMT (Hyperthreading) scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001017 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001018 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001019 SMT scheduler support improves the CPU scheduler's decision making
1020 when dealing with Intel Pentium 4 chips with HyperThreading at a
1021 cost of slightly increased overhead in some places. If unsure say
1022 N here.
1023
1024config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001025 def_bool y
1026 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001027 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001028 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001029 Multi-core scheduler support improves the CPU scheduler's decision
1030 making when dealing with multi-core CPU chips at a cost of slightly
1031 increased overhead in some places. If unsure say N here.
1032
Tim Chende966cf2016-11-29 10:43:27 -08001033config SCHED_MC_PRIO
1034 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001035 depends on SCHED_MC && CPU_SUP_INTEL
1036 select X86_INTEL_PSTATE
1037 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001038 default y
Tim Chen5e76b2a2016-11-22 12:23:55 -08001039 ---help---
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001040 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1041 core ordering determined at manufacturing time, which allows
1042 certain cores to reach higher turbo frequencies (when running
1043 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001044
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001045 Enabling this kernel feature teaches the scheduler about
1046 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1047 scheduler's CPU selection logic accordingly, so that higher
1048 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001049
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001050 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001051
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001052 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001053
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001054source "kernel/Kconfig.preempt"
1055
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001056config UP_LATE_INIT
1057 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +01001058 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001059
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001060config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001061 bool "Local APIC support on uniprocessors" if !PCI_MSI
1062 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001063 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001064 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001065 A local APIC (Advanced Programmable Interrupt Controller) is an
1066 integrated interrupt controller in the CPU. If you have a single-CPU
1067 system which has a processor with a local APIC, you can say Y here to
1068 enable and use it. If you say Y here even though your machine doesn't
1069 have a local APIC, then the kernel will still run with no slowdown at
1070 all. The local APIC supports CPU-generated self-interrupts (timer,
1071 performance counters), and the NMI watchdog which detects hard
1072 lockups.
1073
1074config X86_UP_IOAPIC
1075 bool "IO-APIC support on uniprocessors"
1076 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001077 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001078 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1079 SMP-capable replacement for PC-style interrupt controllers. Most
1080 SMP systems and many recent uniprocessor systems have one.
1081
1082 If you have a single-CPU system with an IO-APIC, you can say Y here
1083 to use it. If you say Y here even though your machine doesn't have
1084 an IO-APIC, then the kernel will still run with no slowdown at all.
1085
1086config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001087 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001088 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001089 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001090 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001091
1092config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001093 def_bool y
1094 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001095
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001096config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1097 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001098 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001099 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001100 This option enables a workaround that fixes a source of
1101 spurious interrupts. This is recommended when threaded
1102 interrupt handling is used on systems where the generation of
1103 superfluous "boot interrupts" cannot be disabled.
1104
1105 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1106 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1107 kernel does during interrupt handling). On chipsets where this
1108 boot IRQ generation cannot be disabled, this workaround keeps
1109 the original IRQ line masked so that only the equivalent "boot
1110 IRQ" is delivered to the CPUs. The workaround also tells the
1111 kernel to set up the IRQ handler on the boot IRQ line. In this
1112 way only one interrupt is delivered to the kernel. Otherwise
1113 the spurious second interrupt may cause the kernel to bring
1114 down (vital) interrupt lines.
1115
1116 Only affects "broken" chipsets. Interrupt sharing may be
1117 increased on these systems.
1118
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001119config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001120 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001121 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001122 default y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001123 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +02001124 Machine Check support allows the processor to notify the
1125 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001126 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001127 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001128
Tony Luck5de97c92017-03-27 11:33:03 +02001129config X86_MCELOG_LEGACY
1130 bool "Support for deprecated /dev/mcelog character device"
1131 depends on X86_MCE
1132 ---help---
1133 Enable support for /dev/mcelog which is needed by the old mcelog
1134 userspace logging daemon. Consider switching to the new generation
1135 rasdaemon solution.
1136
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001137config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001138 def_bool y
1139 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001140 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001141 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001142 Additional support for intel specific MCE features such as
1143 the thermal monitor.
1144
1145config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001146 def_bool y
1147 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001148 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001149 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001150 Additional support for AMD specific MCE features such as
1151 the DRAM Error Threshold.
1152
Andi Kleen4efc0672009-04-28 19:07:31 +02001153config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001154 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001155 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001156 ---help---
1157 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001158 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001159 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001160
Andi Kleenb2762682009-02-12 13:49:31 +01001161config X86_MCE_THRESHOLD
1162 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001163 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001164
Andi Kleenea149b32009-04-29 19:31:00 +02001165config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001166 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001167 tristate "Machine check injector support"
1168 ---help---
1169 Provide support for injecting machine checks for testing purposes.
1170 If you don't know what a machine check is and you don't do kernel
1171 QA it is safe to say n.
1172
Andi Kleen4efc0672009-04-28 19:07:31 +02001173config X86_THERMAL_VECTOR
1174 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001175 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001176
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001177source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001178
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001179config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001180 bool "Legacy VM86 support"
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001181 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001182 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001183 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001184 This option allows user programs to put the CPU into V8086
1185 mode, which is an 80286-era approximation of 16-bit real mode.
1186
1187 Some very old versions of X and/or vbetool require this option
1188 for user mode setting. Similarly, DOSEMU will use it if
1189 available to accelerate real mode DOS programs. However, any
1190 recent version of DOSEMU, X, or vbetool should be fully
1191 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001192 fall back to software emulation. Nevertheless, if you are using
1193 a 16-bit DOS program where 16-bit performance matters, vm86
1194 mode might be faster than emulation and you might want to
1195 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001196
Ingo Molnar1e642812015-09-05 08:58:10 +02001197 Note that any app that works on a 64-bit kernel is unlikely to
1198 need this option, as 64-bit kernels don't, and can't, support
1199 V8086 mode. This option is also unrelated to 16-bit protected
1200 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001201
Ingo Molnar1e642812015-09-05 08:58:10 +02001202 Enabling this option increases the complexity of the kernel
1203 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001204
Ingo Molnar1e642812015-09-05 08:58:10 +02001205 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001206
1207config VM86
1208 bool
1209 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001210
1211config X86_16BIT
1212 bool "Enable support for 16-bit segments" if EXPERT
1213 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001214 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001215 ---help---
1216 This option is required by programs like Wine to run 16-bit
1217 protected mode legacy code on x86 processors. Disabling
1218 this option saves about 300 bytes on i386, or around 6K text
1219 plus 16K runtime memory on x86-64,
1220
1221config X86_ESPFIX32
1222 def_bool y
1223 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001224
H. Peter Anvin197725d2014-05-04 10:00:49 -07001225config X86_ESPFIX64
1226 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001227 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001228
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001229config X86_VSYSCALL_EMULATION
1230 bool "Enable vsyscall emulation" if EXPERT
1231 default y
1232 depends on X86_64
1233 ---help---
1234 This enables emulation of the legacy vsyscall page. Disabling
1235 it is roughly equivalent to booting with vsyscall=none, except
1236 that it will also disable the helpful warning if a program
1237 tries to use a vsyscall. With this option set to N, offending
1238 programs will just segfault, citing addresses of the form
1239 0xffffffffff600?00.
1240
1241 This option is required by many programs built before 2013, and
1242 care should be used even with newer programs if set to N.
1243
1244 Disabling this option saves about 7K of kernel size and
1245 possibly 4K of additional runtime pagetable memory.
1246
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001247config TOSHIBA
1248 tristate "Toshiba Laptop support"
1249 depends on X86_32
1250 ---help---
1251 This adds a driver to safely access the System Management Mode of
1252 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1253 not work on models with a Phoenix BIOS. The System Management Mode
1254 is used to set the BIOS and power saving options on Toshiba portables.
1255
1256 For information on utilities to make use of this driver see the
1257 Toshiba Linux utilities web site at:
1258 <http://www.buzzard.org.uk/toshiba/>.
1259
1260 Say Y if you intend to run this kernel on a Toshiba portable.
1261 Say N otherwise.
1262
1263config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001264 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001265 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001266 select SENSORS_DELL_SMM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001267 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001268 This option enables legacy /proc/i8k userspace interface in hwmon
1269 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1270 temperature and allows controlling fan speeds of Dell laptops via
1271 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1272 it reports also power and hotkey status. For fan speed control is
1273 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001274
Pali Rohár039ae582015-05-14 13:16:37 +02001275 Say Y if you intend to run this kernel on old Dell laptops or want to
1276 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001277 Say N otherwise.
1278
1279config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001280 bool "Enable X86 board specific fixups for reboot"
1281 depends on X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001282 ---help---
1283 This enables chipset and/or board specific fixups to be done
1284 in order to get reboot to work correctly. This is only needed on
1285 some combinations of hardware and BIOS. The symptom, for which
1286 this config is intended, is when reboot ends with a stalled/hung
1287 system.
1288
1289 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001290 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001291
1292 Say Y if you want to enable the fixup. Currently, it's safe to
1293 enable this option even if you don't need it.
1294 Say N otherwise.
1295
1296config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001297 bool "CPU microcode loading support"
1298 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001299 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001300 select FW_LOADER
1301 ---help---
1302 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001303 Intel and AMD processors. The Intel support is for the IA32 family,
1304 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1305 AMD support is for families 0x10 and later. You will obviously need
1306 the actual microcode binary data itself which is not shipped with
1307 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001308
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001309 The preferred method to load microcode from a detached initrd is described
1310 in Documentation/x86/early-microcode.txt. For that you need to enable
1311 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1312 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001313
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001314 In addition, you can build the microcode into the kernel. For that you
1315 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1316 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001317
Peter Oruba8d86f392008-07-28 18:44:21 +02001318config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001319 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001320 depends on MICROCODE
1321 default MICROCODE
1322 select FW_LOADER
1323 ---help---
1324 This options enables microcode patch loading support for Intel
1325 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001326
Alanb8989db2014-01-20 18:01:56 +00001327 For the current Intel microcode data package go to
1328 <https://downloadcenter.intel.com> and search for
1329 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001330
Peter Oruba80cc9f12008-07-28 18:44:22 +02001331config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001332 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001333 depends on MICROCODE
1334 select FW_LOADER
1335 ---help---
1336 If you select this option, microcode patch loading support for AMD
1337 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001338
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001339config MICROCODE_OLD_INTERFACE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001340 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001341 depends on MICROCODE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001342
1343config X86_MSR
1344 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001345 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001346 This device gives privileged processes access to the x86
1347 Model-Specific Registers (MSRs). It is a character device with
1348 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1349 MSR accesses are directed to a specific CPU on multi-processor
1350 systems.
1351
1352config X86_CPUID
1353 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001354 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001355 This device gives processes access to the x86 CPUID instruction to
1356 be executed on a specific processor. It is a character device
1357 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1358 /dev/cpu/31/cpuid.
1359
1360choice
1361 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001362 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001363 depends on X86_32
1364
1365config NOHIGHMEM
1366 bool "off"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001367 ---help---
1368 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1369 However, the address space of 32-bit x86 processors is only 4
1370 Gigabytes large. That means that, if you have a large amount of
1371 physical memory, not all of it can be "permanently mapped" by the
1372 kernel. The physical memory that's not permanently mapped is called
1373 "high memory".
1374
1375 If you are compiling a kernel which will never run on a machine with
1376 more than 1 Gigabyte total physical RAM, answer "off" here (default
1377 choice and suitable for most users). This will result in a "3GB/1GB"
1378 split: 3GB are mapped so that each process sees a 3GB virtual memory
1379 space and the remaining part of the 4GB virtual memory space is used
1380 by the kernel to permanently map as much physical memory as
1381 possible.
1382
1383 If the machine has between 1 and 4 Gigabytes physical RAM, then
1384 answer "4GB" here.
1385
1386 If more than 4 Gigabytes is used then answer "64GB" here. This
1387 selection turns Intel PAE (Physical Address Extension) mode on.
1388 PAE implements 3-level paging on IA32 processors. PAE is fully
1389 supported by Linux, PAE mode is implemented on all recent Intel
1390 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1391 then the kernel will not boot on CPUs that don't support PAE!
1392
1393 The actual amount of total physical memory will either be
1394 auto detected or can be forced by using a kernel command line option
1395 such as "mem=256M". (Try "man bootparam" or see the documentation of
1396 your boot loader (lilo or loadlin) about how to pass options to the
1397 kernel at boot time.)
1398
1399 If unsure, say "off".
1400
1401config HIGHMEM4G
1402 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001403 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001404 Select this if you have a 32-bit processor and between 1 and 4
1405 gigabytes of physical RAM.
1406
1407config HIGHMEM64G
1408 bool "64GB"
Matthew Whitehead69b8d3f2018-02-15 11:54:55 -05001409 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001410 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001411 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001412 Select this if you have a 32-bit processor and more than 4
1413 gigabytes of physical RAM.
1414
1415endchoice
1416
1417choice
David Rientjes6a108a12011-01-20 14:44:16 -08001418 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001419 default VMSPLIT_3G
1420 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001421 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001422 Select the desired split between kernel and user memory.
1423
1424 If the address range available to the kernel is less than the
1425 physical memory installed, the remaining memory will be available
1426 as "high memory". Accessing high memory is a little more costly
1427 than low memory, as it needs to be mapped into the kernel first.
1428 Note that increasing the kernel address space limits the range
1429 available to user programs, making the address space there
1430 tighter. Selecting anything other than the default 3G/1G split
1431 will also likely make your kernel incompatible with binary-only
1432 kernel modules.
1433
1434 If you are not absolutely sure what you are doing, leave this
1435 option alone!
1436
1437 config VMSPLIT_3G
1438 bool "3G/1G user/kernel split"
1439 config VMSPLIT_3G_OPT
1440 depends on !X86_PAE
1441 bool "3G/1G user/kernel split (for full 1G low memory)"
1442 config VMSPLIT_2G
1443 bool "2G/2G user/kernel split"
1444 config VMSPLIT_2G_OPT
1445 depends on !X86_PAE
1446 bool "2G/2G user/kernel split (for full 2G low memory)"
1447 config VMSPLIT_1G
1448 bool "1G/3G user/kernel split"
1449endchoice
1450
1451config PAGE_OFFSET
1452 hex
1453 default 0xB0000000 if VMSPLIT_3G_OPT
1454 default 0x80000000 if VMSPLIT_2G
1455 default 0x78000000 if VMSPLIT_2G_OPT
1456 default 0x40000000 if VMSPLIT_1G
1457 default 0xC0000000
1458 depends on X86_32
1459
1460config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001461 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001462 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001463
1464config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001465 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001466 depends on X86_32 && !HIGHMEM4G
Christian Melki9d99c712015-10-05 17:31:33 +02001467 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001468 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001469 PAE is required for NX support, and furthermore enables
1470 larger swapspace support for non-overcommit purposes. It
1471 has the cost of more pagetable lookup overhead, and also
1472 consumes more pagetable space per process.
1473
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001474config X86_5LEVEL
1475 bool "Enable 5-level page tables support"
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001476 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001477 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001478 depends on X86_64
1479 ---help---
1480 5-level paging enables access to larger address space:
1481 upto 128 PiB of virtual address space and 4 PiB of
1482 physical address space.
1483
1484 It will be supported by future Intel CPUs.
1485
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001486 A kernel with the option enabled can be booted on machines that
1487 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001488
1489 See Documentation/x86/x86_64/5level-paging.txt for more
1490 information.
1491
1492 Say N if unsure.
1493
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001494config ARCH_PHYS_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001495 def_bool y
1496 depends on X86_64 || X86_PAE
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001497
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001498config ARCH_DMA_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001499 def_bool y
1500 depends on X86_64 || HIGHMEM64G
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001501
Ingo Molnar10971ab2015-03-05 08:18:23 +01001502config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001503 def_bool y
Levin, Alexander (Sasha Levin)4675ff02017-11-15 17:36:02 -08001504 depends on X86_64 && !DEBUG_PAGEALLOC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001505 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001506 Certain kernel features effectively disable kernel
1507 linear 1 GB mappings (even if the CPU otherwise
1508 supports them), so don't confuse the user by printing
1509 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001510
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001511config ARCH_HAS_MEM_ENCRYPT
1512 def_bool y
1513
1514config AMD_MEM_ENCRYPT
1515 bool "AMD Secure Memory Encryption (SME) support"
1516 depends on X86_64 && CPU_SUP_AMD
1517 ---help---
1518 Say yes to enable support for the encryption of system memory.
1519 This requires an AMD processor that supports Secure Memory
1520 Encryption (SME).
1521
1522config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1523 bool "Activate AMD Secure Memory Encryption (SME) by default"
1524 default y
1525 depends on AMD_MEM_ENCRYPT
1526 ---help---
1527 Say yes to have system memory encrypted by default if running on
1528 an AMD processor that supports Secure Memory Encryption (SME).
1529
1530 If set to Y, then the encryption of system memory can be
1531 deactivated with the mem_encrypt=off command line option.
1532
1533 If set to N, then the encryption of system memory can be
1534 activated with the mem_encrypt=on command line option.
1535
Tom Lendackyf88a68f2017-07-17 16:10:09 -05001536config ARCH_USE_MEMREMAP_PROT
1537 def_bool y
1538 depends on AMD_MEM_ENCRYPT
1539
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001540# Common NUMA Features
1541config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001542 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001543 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001544 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1545 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001546 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001547 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001548
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001549 The kernel will try to allocate memory used by a CPU on the
1550 local memory controller of the CPU and add some more
1551 NUMA awareness to the kernel.
1552
Ingo Molnarc280ea52008-11-08 13:29:45 +01001553 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001554 (or later), AMD Opteron, or EM64T NUMA.
1555
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001556 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001557 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001558
1559 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001560
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001561config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001562 def_bool y
1563 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001564 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001565 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001566 Enable AMD NUMA node topology detection. You should say Y here if
1567 you have a multi processor AMD system. This uses an old method to
1568 read the NUMA configuration directly from the builtin Northbridge
1569 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1570 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001571
1572config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001573 def_bool y
1574 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001575 depends on X86_64 && NUMA && ACPI && PCI
1576 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001577 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001578 Enable ACPI SRAT based node topology detection.
1579
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001580# Some NUMA nodes have memory ranges that span
1581# other nodes. Even though a pfn is valid and
1582# between a node's start and end pfns, it may not
1583# reside on that node. See memmap_init_zone()
1584# for details.
1585config NODES_SPAN_OTHER_NODES
1586 def_bool y
1587 depends on X86_64_ACPI_NUMA
1588
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001589config NUMA_EMU
1590 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001591 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001592 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001593 Enable NUMA emulation. A flat machine will be split
1594 into virtual nodes when booted with "numa=fake=N", where N is the
1595 number of nodes. This is only useful for debugging.
1596
1597config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001598 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001599 range 1 10
1600 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001601 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001602 default "3"
1603 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001604 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001605 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001606 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001607
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001608config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001609 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001610 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001611
1612config NEED_NODE_MEMMAP_SIZE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001613 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001614 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001615
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001616config ARCH_FLATMEM_ENABLE
1617 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001618 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001619
1620config ARCH_DISCONTIGMEM_ENABLE
1621 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001622 depends on NUMA && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001623
1624config ARCH_DISCONTIGMEM_DEFAULT
1625 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001626 depends on NUMA && X86_32
1627
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001628config ARCH_SPARSEMEM_ENABLE
1629 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001630 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001631 select SPARSEMEM_STATIC if X86_32
1632 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1633
Tejun Heo3b166512011-04-01 11:15:12 +02001634config ARCH_SPARSEMEM_DEFAULT
1635 def_bool y
1636 depends on X86_64
1637
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001638config ARCH_SELECT_MEMORY_MODEL
1639 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001640 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001641
1642config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001643 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001644 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001645 help
1646 This option enables a sysfs memory/probe interface for testing.
1647 See Documentation/memory-hotplug.txt for more information.
1648 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001649
Tejun Heo3b166512011-04-01 11:15:12 +02001650config ARCH_PROC_KCORE_TEXT
1651 def_bool y
1652 depends on X86_64 && PROC_KCORE
1653
Avi Kivitya29815a2010-01-10 16:28:09 +02001654config ILLEGAL_POINTER_VALUE
1655 hex
1656 default 0 if X86_32
1657 default 0xdead000000000000 if X86_64
1658
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001659source "mm/Kconfig"
1660
Dan Williams7a678322015-08-19 00:34:34 -04001661config X86_PMEM_LEGACY_DEVICE
1662 bool
1663
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001664config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001665 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001666 depends on PHYS_ADDR_T_64BIT
1667 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001668 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001669 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001670 help
1671 Treat memory marked using the non-standard e820 type of 12 as used
1672 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1673 The kernel will offer these regions to the 'pmem' driver so
1674 they can be used for persistent storage.
1675
1676 Say Y if unsure.
1677
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001678config HIGHPTE
1679 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001680 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001681 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001682 The VM uses one page table entry for each page of physical memory.
1683 For systems with a lot of RAM, this can be wasteful of precious
1684 low memory. Setting this option will put user-space page table
1685 entries in high memory.
1686
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001687config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001688 bool "Check for low memory corruption"
1689 ---help---
1690 Periodically check for memory corruption in low memory, which
1691 is suspected to be caused by BIOS. Even when enabled in the
1692 configuration, it is disabled at runtime. Enable it by
1693 setting "memory_corruption_check=1" on the kernel command
1694 line. By default it scans the low 64k of memory every 60
1695 seconds; see the memory_corruption_check_size and
1696 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001697 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001698
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001699 When enabled with the default parameters, this option has
1700 almost no overhead, as it reserves a relatively small amount
1701 of memory and scans it infrequently. It both detects corruption
1702 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001703
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001704 It is, however, intended as a diagnostic tool; if repeatable
1705 BIOS-originated corruption always affects the same memory,
1706 you can use memmap= to prevent the kernel from using that
1707 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001708
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001709config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001710 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001711 depends on X86_CHECK_BIOS_CORRUPTION
1712 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001713 ---help---
1714 Set whether the default state of memory_corruption_check is
1715 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001716
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001717config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001718 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1719 default 64
1720 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001721 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001722 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001723
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001724 The first page contains BIOS data structures that the kernel
1725 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001726
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001727 By default we reserve the first 64K of physical RAM, as a
1728 number of BIOSes are known to corrupt that memory range
1729 during events such as suspend/resume or monitor cable
1730 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001731
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001732 You can set this to 4 if you are absolutely sure that you
1733 trust the BIOS to get all its memory reservations and usages
1734 right. If you know your BIOS have problems beyond the
1735 default 64K area, you can set this to 640 to avoid using the
1736 entire low memory range.
1737
1738 If you have doubts about the BIOS (e.g. suspend/resume does
1739 not work or there's kernel crashes after certain hardware
1740 hotplug events) then you might want to enable
1741 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1742 typical corruption patterns.
1743
1744 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001745
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001746config MATH_EMULATION
1747 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001748 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001749 prompt "Math emulation" if X86_32
1750 ---help---
1751 Linux can emulate a math coprocessor (used for floating point
1752 operations) if you don't have one. 486DX and Pentium processors have
1753 a math coprocessor built in, 486SX and 386 do not, unless you added
1754 a 487DX or 387, respectively. (The messages during boot time can
1755 give you some hints here ["man dmesg"].) Everyone needs either a
1756 coprocessor or this emulation.
1757
1758 If you don't have a math coprocessor, you need to say Y here; if you
1759 say Y here even though you have a coprocessor, the coprocessor will
1760 be used nevertheless. (This behavior can be changed with the kernel
1761 command line option "no387", which comes handy if your coprocessor
1762 is broken. Try "man bootparam" or see the documentation of your boot
1763 loader (lilo or loadlin) about how to pass options to the kernel at
1764 boot time.) This means that it is a good idea to say Y here if you
1765 intend to use this kernel on different machines.
1766
1767 More information about the internals of the Linux math coprocessor
1768 emulation can be found in <file:arch/x86/math-emu/README>.
1769
1770 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1771 kernel, it won't hurt.
1772
1773config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001774 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001775 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001776 ---help---
1777 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1778 the Memory Type Range Registers (MTRRs) may be used to control
1779 processor access to memory ranges. This is most useful if you have
1780 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1781 allows bus write transfers to be combined into a larger transfer
1782 before bursting over the PCI/AGP bus. This can increase performance
1783 of image write operations 2.5 times or more. Saying Y here creates a
1784 /proc/mtrr file which may be used to manipulate your processor's
1785 MTRRs. Typically the X server should use this.
1786
1787 This code has a reasonably generic interface so that similar
1788 control registers on other processors can be easily supported
1789 as well:
1790
1791 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1792 Registers (ARRs) which provide a similar functionality to MTRRs. For
1793 these, the ARRs are used to emulate the MTRRs.
1794 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1795 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1796 write-combining. All of these processors are supported by this code
1797 and it makes sense to say Y here if you have one of them.
1798
1799 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1800 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1801 can lead to all sorts of problems, so it's good to say Y here.
1802
1803 You can safely say Y even if your machine doesn't have MTRRs, you'll
1804 just add about 9 KB to your kernel.
1805
Randy Dunlap7225e752008-07-26 17:54:22 -07001806 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001807
Yinghai Lu95ffa242008-04-29 03:52:33 -07001808config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001809 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001810 prompt "MTRR cleanup support"
1811 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001812 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001813 Convert MTRR layout from continuous to discrete, so X drivers can
1814 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001815
Thomas Gleixneraba37282008-07-15 14:48:48 +02001816 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001817 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001818 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001819
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001820 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001821
1822config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001823 int "MTRR cleanup enable value (0-1)"
1824 range 0 1
1825 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001826 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001827 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001828 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001829
Yinghai Lu12031a62008-05-02 02:40:22 -07001830config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1831 int "MTRR cleanup spare reg num (0-7)"
1832 range 0 7
1833 default "1"
1834 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001835 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001836 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001837 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001838
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001839config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001840 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001841 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001842 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001843 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001844 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001845
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001846 PATs are the modern equivalents of MTRRs and are much more
1847 flexible than MTRRs.
1848
1849 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001850 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001851
1852 If unsure, say Y.
1853
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001854config ARCH_USES_PG_UNCACHED
1855 def_bool y
1856 depends on X86_PAT
1857
H. Peter Anvin628c6242011-07-31 13:59:29 -07001858config ARCH_RANDOM
1859 def_bool y
1860 prompt "x86 architectural random number generator" if EXPERT
1861 ---help---
1862 Enable the x86 architectural RDRAND instruction
1863 (Intel Bull Mountain technology) to generate random numbers.
1864 If supported, this is a high bandwidth, cryptographically
1865 secure hardware random number generator.
1866
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001867config X86_SMAP
1868 def_bool y
1869 prompt "Supervisor Mode Access Prevention" if EXPERT
1870 ---help---
1871 Supervisor Mode Access Prevention (SMAP) is a security
1872 feature in newer Intel processors. There is a small
1873 performance cost if this enabled and turned on; there is
1874 also a small increase in the kernel size if this is enabled.
1875
1876 If unsure, say Y.
1877
Ricardo Neriaa35f892017-11-05 18:27:54 -08001878config X86_INTEL_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001879 def_bool y
Ricardo Neriaa35f892017-11-05 18:27:54 -08001880 depends on CPU_SUP_INTEL
1881 prompt "Intel User Mode Instruction Prevention" if EXPERT
1882 ---help---
1883 The User Mode Instruction Prevention (UMIP) is a security
1884 feature in newer Intel processors. If enabled, a general
Ricardo Neri796ebc82017-11-13 22:29:42 -08001885 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1886 or STR instructions are executed in user mode. These instructions
1887 unnecessarily expose information about the hardware state.
1888
1889 The vast majority of applications do not use these instructions.
1890 For the very few that do, software emulation is provided in
1891 specific cases in protected and virtual-8086 modes. Emulated
1892 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001893
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001894config X86_INTEL_MPX
1895 prompt "Intel MPX (Memory Protection Extensions)"
1896 def_bool n
Rik van Rieldf3735c2017-09-06 16:25:11 -07001897 # Note: only available in 64-bit mode due to VMA flags shortage
1898 depends on CPU_SUP_INTEL && X86_64
1899 select ARCH_USES_HIGH_VMA_FLAGS
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001900 ---help---
1901 MPX provides hardware features that can be used in
1902 conjunction with compiler-instrumented code to check
1903 memory references. It is designed to detect buffer
1904 overflow or underflow bugs.
1905
1906 This option enables running applications which are
1907 instrumented or otherwise use MPX. It does not use MPX
1908 itself inside the kernel or to protect the kernel
1909 against bad memory references.
1910
1911 Enabling this option will make the kernel larger:
1912 ~8k of kernel text and 36 bytes of data on a 64-bit
1913 defconfig. It adds a long to the 'mm_struct' which
1914 will increase the kernel memory overhead of each
1915 process and adds some branches to paths used during
1916 exec() and munmap().
1917
1918 For details, see Documentation/x86/intel_mpx.txt
1919
1920 If unsure, say N.
1921
Dave Hansen35e97792016-02-12 13:02:00 -08001922config X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001923 prompt "Intel Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001924 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001925 # Note: only available in 64-bit mode
Dave Hansen35e97792016-02-12 13:02:00 -08001926 depends on CPU_SUP_INTEL && X86_64
Ingo Molnar52c8e602016-11-15 10:15:03 +01001927 select ARCH_USES_HIGH_VMA_FLAGS
1928 select ARCH_HAS_PKEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001929 ---help---
1930 Memory Protection Keys provides a mechanism for enforcing
1931 page-based protections, but without requiring modification of the
1932 page tables when an application changes protection domains.
1933
1934 For details, see Documentation/x86/protection-keys.txt
1935
1936 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001937
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001938config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001939 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001940 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001941 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001942 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001943 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001944 This enables the kernel to use EFI runtime services that are
1945 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001946
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001947 This option is only useful on systems that have EFI firmware.
1948 In addition, you should use the latest ELILO loader available
1949 at <http://elilo.sourceforge.net> in order to take advantage
1950 of EFI runtime services. However, even with this option, the
1951 resultant kernel should continue to boot on existing non-EFI
1952 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001953
Matt Fleming291f3632011-12-12 21:27:52 +00001954config EFI_STUB
1955 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001956 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001957 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001958 ---help---
1959 This kernel feature allows a bzImage to be loaded directly
1960 by EFI firmware without the use of a bootloader.
1961
Roy Franz4172fe22013-09-22 15:45:25 -07001962 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001963
Matt Fleming7d453ee2014-01-10 18:52:06 +00001964config EFI_MIXED
1965 bool "EFI mixed-mode support"
1966 depends on EFI_STUB && X86_64
1967 ---help---
1968 Enabling this feature allows a 64-bit kernel to be booted
1969 on a 32-bit firmware, provided that your CPU supports 64-bit
1970 mode.
1971
1972 Note that it is not possible to boot a mixed-mode enabled
1973 kernel via the EFI boot stub - a bootloader that supports
1974 the EFI handover protocol must be used.
1975
1976 If unsure, say N.
1977
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001978config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001979 def_bool y
1980 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001981 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001982 This kernel feature is useful for number crunching applications
1983 that may need to compute untrusted bytecode during their
1984 execution. By using pipes or other transports made available to
1985 the process as file descriptors supporting the read/write
1986 syscalls, it's possible to isolate those applications in
1987 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001988 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001989 and the task is only allowed to execute a few safe syscalls
1990 defined by each seccomp mode.
1991
1992 If unsure, say Y. Only embedded should say N here.
1993
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001994source kernel/Kconfig.hz
1995
1996config KEXEC
1997 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001998 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001999 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002000 kexec is a system call that implements the ability to shutdown your
2001 current kernel, and to start another kernel. It is like a reboot
2002 but it is independent of the system firmware. And like a reboot
2003 you can start any kernel with it, not just Linux.
2004
2005 The name comes from the similarity to the exec system call.
2006
2007 It is an ongoing process to be certain the hardware in a machine
2008 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02002009 initially work for you. As of this writing the exact hardware
2010 interface is strongly in flux, so no good recommendation can be
2011 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002012
Vivek Goyal74ca3172014-08-29 15:18:46 -07002013config KEXEC_FILE
2014 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07002015 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07002016 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07002017 depends on X86_64
2018 depends on CRYPTO=y
2019 depends on CRYPTO_SHA256=y
2020 ---help---
2021 This is new version of kexec system call. This system call is
2022 file based and takes file descriptors as system call argument
2023 for kernel and initramfs as opposed to list of segments as
2024 accepted by previous system call.
2025
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002026config KEXEC_VERIFY_SIG
2027 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07002028 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002029 ---help---
2030 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002031 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002032
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002033 In addition to that option, you need to enable signature
2034 verification for the corresponding kernel image type being
2035 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002036
2037config KEXEC_BZIMAGE_VERIFY_SIG
2038 bool "Enable bzImage signature verification support"
2039 depends on KEXEC_VERIFY_SIG
2040 depends on SIGNED_PE_FILE_VERIFICATION
2041 select SYSTEM_TRUSTED_KEYRING
2042 ---help---
2043 Enable bzImage signature verification support.
2044
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002045config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002046 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002047 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002048 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002049 Generate crash dump after being started by kexec.
2050 This should be normally only set in special crash dump kernels
2051 which are loaded in the main kernel with kexec-tools into
2052 a specially reserved region and then later executed after
2053 a crash by kdump/kexec. The crash dump kernel must be compiled
2054 to a memory address not used by the main kernel or BIOS using
2055 PHYSICAL_START, or it must be built as a relocatable image
2056 (CONFIG_RELOCATABLE=y).
2057 For more details see Documentation/kdump/kdump.txt
2058
Huang Ying3ab83522008-07-25 19:45:07 -07002059config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002060 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002061 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002062 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07002063 Jump between original kernel and kexeced kernel and invoke
2064 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002065
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002066config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002067 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002068 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002069 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002070 This gives the physical address where the kernel is loaded.
2071
2072 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2073 bzImage will decompress itself to above physical address and
2074 run from there. Otherwise, bzImage will run from the address where
2075 it has been loaded by the boot loader and will ignore above physical
2076 address.
2077
2078 In normal kdump cases one does not have to set/change this option
2079 as now bzImage can be compiled as a completely relocatable image
2080 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2081 address. This option is mainly useful for the folks who don't want
2082 to use a bzImage for capturing the crash dump and want to use a
2083 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2084 to be specifically compiled to run from a specific memory area
2085 (normally a reserved region) and this option comes handy.
2086
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002087 So if you are using bzImage for capturing the crash dump,
2088 leave the value here unchanged to 0x1000000 and set
2089 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2090 for capturing the crash dump change this value to start of
2091 the reserved region. In other words, it can be set based on
2092 the "X" value as specified in the "crashkernel=YM@XM"
2093 command line boot parameter passed to the panic-ed
2094 kernel. Please take a look at Documentation/kdump/kdump.txt
2095 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002096
2097 Usage of bzImage for capturing the crash dump is recommended as
2098 one does not have to build two kernels. Same kernel can be used
2099 as production kernel and capture kernel. Above option should have
2100 gone away after relocatable bzImage support is introduced. But it
2101 is present because there are users out there who continue to use
2102 vmlinux for dump capture. This option should go away down the
2103 line.
2104
2105 Don't change this unless you know what you are doing.
2106
2107config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002108 bool "Build a relocatable kernel"
2109 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002110 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002111 This builds a kernel image that retains relocation information
2112 so it can be loaded someplace besides the default 1MB.
2113 The relocations tend to make the kernel binary about 10% larger,
2114 but are discarded at runtime.
2115
2116 One use is for the kexec on panic case where the recovery kernel
2117 must live at a different physical address than the primary
2118 kernel.
2119
2120 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2121 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002122 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002123
Kees Cook8ab38202013-10-10 17:18:14 -07002124config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002125 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002126 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002127 default y
Kees Cook8ab38202013-10-10 17:18:14 -07002128 ---help---
Baoquan Hee8581e32016-04-20 13:55:43 -07002129 In support of Kernel Address Space Layout Randomization (KASLR),
2130 this randomizes the physical address at which the kernel image
2131 is decompressed and the virtual address where the kernel
2132 image is mapped, as a security feature that deters exploit
2133 attempts relying on knowledge of the location of kernel
2134 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002135
Kees Cooked9f0072016-05-25 15:45:33 -07002136 On 64-bit, the kernel physical and virtual addresses are
2137 randomized separately. The physical address will be anywhere
2138 between 16MB and the top of physical memory (up to 64TB). The
2139 virtual address will be randomized from 16MB up to 1GB (9 bits
2140 of entropy). Note that this also reduces the memory space
2141 available to kernel modules from 1.5GB to 1GB.
2142
2143 On 32-bit, the kernel physical and virtual addresses are
2144 randomized together. They will be randomized from 16MB up to
2145 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002146
Baoquan Hee8581e32016-04-20 13:55:43 -07002147 Entropy is generated using the RDRAND instruction if it is
2148 supported. If RDTSC is supported, its value is mixed into
2149 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002150 supported, then entropy is read from the i8254 timer. The
2151 usable entropy is limited by the kernel being built using
2152 2GB addressing, and that PHYSICAL_ALIGN must be at a
2153 minimum of 2MB. As a result, only 10 bits of entropy are
2154 theoretically possible, but the implementations are further
2155 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002156
Ingo Molnar6807c842017-04-18 11:08:12 +02002157 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002158
2159# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002160config X86_NEED_RELOCS
2161 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002162 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002163
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002164config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002165 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002166 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002167 range 0x2000 0x1000000 if X86_32
2168 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002169 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002170 This value puts the alignment restrictions on physical address
2171 where kernel is loaded and run from. Kernel is compiled for an
2172 address which meets above alignment restriction.
2173
2174 If bootloader loads the kernel at a non-aligned address and
2175 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2176 address aligned to above value and run from there.
2177
2178 If bootloader loads the kernel at a non-aligned address and
2179 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2180 load address and decompress itself to the address it has been
2181 compiled for and run from there. The address for which kernel is
2182 compiled already meets above alignment restrictions. Hence the
2183 end result is that kernel runs from a physical address meeting
2184 above alignment restrictions.
2185
Kees Cooka0215062013-07-08 09:15:17 -07002186 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2187 this value must be a multiple of 0x200000.
2188
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002189 Don't change this unless you know what you are doing.
2190
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002191config DYNAMIC_MEMORY_LAYOUT
2192 bool
2193 ---help---
2194 This option makes base addresses of vmalloc and vmemmap as well as
2195 __PAGE_OFFSET movable during boot.
2196
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002197config RANDOMIZE_MEMORY
2198 bool "Randomize the kernel memory sections"
2199 depends on X86_64
2200 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002201 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002202 default RANDOMIZE_BASE
2203 ---help---
2204 Randomizes the base virtual address of kernel memory sections
2205 (physical memory mapping, vmalloc & vmemmap). This security feature
2206 makes exploits relying on predictable memory locations less reliable.
2207
2208 The order of allocations remains unchanged. Entropy is generated in
2209 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2210 configuration have in average 30,000 different possible virtual
2211 addresses for each memory section.
2212
Ingo Molnar6807c842017-04-18 11:08:12 +02002213 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002214
Thomas Garnier90397a42016-06-21 17:47:06 -07002215config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2216 hex "Physical memory mapping padding" if EXPERT
2217 depends on RANDOMIZE_MEMORY
2218 default "0xa" if MEMORY_HOTPLUG
2219 default "0x0"
2220 range 0x1 0x40 if MEMORY_HOTPLUG
2221 range 0x0 0x40
2222 ---help---
2223 Define the padding in terabytes added to the existing physical
2224 memory size during kernel memory randomization. It is useful
2225 for memory hotplug support but reduces the entropy available for
2226 address randomization.
2227
2228 If unsure, leave at the default value.
2229
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002230config HOTPLUG_CPU
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002231 bool "Support for hot-pluggable CPUs"
Stephen Rothwell40b31362013-05-21 13:49:35 +10002232 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002233 ---help---
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002234 Say Y here to allow turning CPUs off and on. CPUs can be
2235 controlled through /sys/devices/system/cpu.
2236 ( Note: power management support will enable this option
2237 automatically on SMP systems. )
2238 Say N if you want to disable CPU hotplug.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002239
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002240config BOOTPARAM_HOTPLUG_CPU0
2241 bool "Set default setting of cpu0_hotpluggable"
2242 default n
Kees Cook2c922cd2013-01-22 13:01:19 -08002243 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002244 ---help---
2245 Set whether default state of cpu0_hotpluggable is on or off.
2246
2247 Say Y here to enable CPU0 hotplug by default. If this switch
2248 is turned on, there is no need to give cpu0_hotplug kernel
2249 parameter and the CPU0 hotplug feature is enabled by default.
2250
2251 Please note: there are two known CPU0 dependencies if you want
2252 to enable the CPU0 hotplug feature either by this switch or by
2253 cpu0_hotplug kernel parameter.
2254
2255 First, resume from hibernate or suspend always starts from CPU0.
2256 So hibernate and suspend are prevented if CPU0 is offline.
2257
2258 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2259 offline if any interrupt can not migrate out of CPU0. There may
2260 be other CPU0 dependencies.
2261
2262 Please make sure the dependencies are under your control before
2263 you enable this feature.
2264
2265 Say N if you don't want to enable CPU0 hotplug feature by default.
2266 You still can enable the CPU0 hotplug feature at boot by kernel
2267 parameter cpu0_hotplug.
2268
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002269config DEBUG_HOTPLUG_CPU0
2270 def_bool n
2271 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002272 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002273 ---help---
2274 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2275 soon as possible and boots up userspace with CPU0 offlined. User
2276 can online CPU0 back after boot time.
2277
2278 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2279 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2280 compilation or giving cpu0_hotplug kernel parameter at boot.
2281
2282 If unsure, say N.
2283
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002284config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002285 def_bool n
2286 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002287 depends on COMPAT_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002288 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002289 Certain buggy versions of glibc will crash if they are
2290 presented with a 32-bit vDSO that is not mapped at the address
2291 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002292
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002293 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2294 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2295 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2296 the only released version with the bug, but OpenSUSE 9
2297 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002298
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002299 The symptom of the bug is that everything crashes on startup, saying:
2300 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2301
2302 Saying Y here changes the default value of the vdso32 boot
2303 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2304 This works around the glibc bug but hurts performance.
2305
2306 If unsure, say N: if you are compiling your own kernel, you
2307 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002308
Kees Cook3dc33bd2015-08-12 17:55:19 -07002309choice
2310 prompt "vsyscall table for legacy applications"
2311 depends on X86_64
2312 default LEGACY_VSYSCALL_EMULATE
2313 help
2314 Legacy user code that does not know how to find the vDSO expects
2315 to be able to issue three syscalls by calling fixed addresses in
2316 kernel space. Since this location is not randomized with ASLR,
2317 it can be used to assist security vulnerability exploitation.
2318
2319 This setting can be changed at boot time via the kernel command
Andy Lutomirski076ca272018-03-07 11:12:27 -08002320 line parameter vsyscall=[emulate|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002321
2322 On a system with recent enough glibc (2.14 or newer) and no
2323 static binaries, you can say None without a performance penalty
2324 to improve security.
2325
2326 If unsure, select "Emulate".
2327
Kees Cook3dc33bd2015-08-12 17:55:19 -07002328 config LEGACY_VSYSCALL_EMULATE
2329 bool "Emulate"
2330 help
2331 The kernel traps and emulates calls into the fixed
2332 vsyscall address mapping. This makes the mapping
2333 non-executable, but it still contains known contents,
2334 which could be used in certain rare security vulnerability
2335 exploits. This configuration is recommended when userspace
2336 still uses the vsyscall area.
2337
2338 config LEGACY_VSYSCALL_NONE
2339 bool "None"
2340 help
2341 There will be no vsyscall mapping at all. This will
2342 eliminate any risk of ASLR bypass due to the vsyscall
2343 fixed address mapping. Attempts to use the vsyscalls
2344 will be reported to dmesg, so that either old or
2345 malicious userspace programs can be identified.
2346
2347endchoice
2348
Tim Bird516cbf32008-08-12 12:52:36 -07002349config CMDLINE_BOOL
2350 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002351 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002352 Allow for specifying boot arguments to the kernel at
2353 build time. On some systems (e.g. embedded ones), it is
2354 necessary or convenient to provide some or all of the
2355 kernel boot arguments with the kernel itself (that is,
2356 to not rely on the boot loader to provide them.)
2357
2358 To compile command line arguments into the kernel,
2359 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002360 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002361
2362 Systems with fully functional boot loaders (i.e. non-embedded)
2363 should leave this option set to 'N'.
2364
2365config CMDLINE
2366 string "Built-in kernel command string"
2367 depends on CMDLINE_BOOL
2368 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002369 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002370 Enter arguments here that should be compiled into the kernel
2371 image and used at boot time. If the boot loader provides a
2372 command line at boot time, it is appended to this string to
2373 form the full kernel command line, when the system boots.
2374
2375 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2376 change this behavior.
2377
2378 In most cases, the command line (whether built-in or provided
2379 by the boot loader) should specify the device for the root
2380 file system.
2381
2382config CMDLINE_OVERRIDE
2383 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002384 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002385 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002386 Set this option to 'Y' to have the kernel ignore the boot loader
2387 command line, and use ONLY the built-in command line.
2388
2389 This is used to work around broken boot loaders. This should
2390 be set to 'N' under normal conditions.
2391
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002392config MODIFY_LDT_SYSCALL
2393 bool "Enable the LDT (local descriptor table)" if EXPERT
2394 default y
2395 ---help---
2396 Linux can allow user programs to install a per-process x86
2397 Local Descriptor Table (LDT) using the modify_ldt(2) system
2398 call. This is required to run 16-bit or segmented code such as
2399 DOSEMU or some Wine programs. It is also used by some very old
2400 threading libraries.
2401
2402 Enabling this feature adds a small amount of overhead to
2403 context switches and increases the low-level kernel attack
2404 surface. Disabling it removes the modify_ldt(2) system call.
2405
2406 Saying 'N' here may make sense for embedded or server kernels.
2407
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002408source "kernel/livepatch/Kconfig"
2409
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002410endmenu
2411
Michal Hocko3072e412017-09-08 16:11:39 -07002412config ARCH_HAS_ADD_PAGES
2413 def_bool y
2414 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2415
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002416config ARCH_ENABLE_MEMORY_HOTPLUG
2417 def_bool y
2418 depends on X86_64 || (X86_32 && HIGHMEM)
2419
Gary Hade35551052008-10-31 10:52:03 -07002420config ARCH_ENABLE_MEMORY_HOTREMOVE
2421 def_bool y
2422 depends on MEMORY_HOTPLUG
2423
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002424config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002425 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002426 depends on NUMA
2427
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002428config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2429 def_bool y
2430 depends on X86_64 || X86_PAE
2431
Naoya Horiguchic177c812014-06-04 16:05:35 -07002432config ARCH_ENABLE_HUGEPAGE_MIGRATION
2433 def_bool y
2434 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2435
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002436config ARCH_ENABLE_THP_MIGRATION
2437 def_bool y
2438 depends on X86_64 && TRANSPARENT_HUGEPAGE
2439
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002440menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002441
2442config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002443 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002444 depends on X86_64 && HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002445
2446source "kernel/power/Kconfig"
2447
2448source "drivers/acpi/Kconfig"
2449
Feng Tangefafc8b2009-08-14 15:23:29 -04002450source "drivers/sfi/Kconfig"
2451
Andi Kleena6b68072008-01-30 13:32:49 +01002452config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002453 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002454 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002455
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002456menuconfig APM
2457 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002458 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002459 ---help---
2460 APM is a BIOS specification for saving power using several different
2461 techniques. This is mostly useful for battery powered laptops with
2462 APM compliant BIOSes. If you say Y here, the system time will be
2463 reset after a RESUME operation, the /proc/apm device will provide
2464 battery status information, and user-space programs will receive
2465 notification of APM "events" (e.g. battery status change).
2466
2467 If you select "Y" here, you can disable actual use of the APM
2468 BIOS by passing the "apm=off" option to the kernel at boot time.
2469
2470 Note that the APM support is almost completely disabled for
2471 machines with more than one CPU.
2472
2473 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002474 and more information, read <file:Documentation/power/apm-acpi.txt>
2475 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002476 <http://www.tldp.org/docs.html#howto>.
2477
2478 This driver does not spin down disk drives (see the hdparm(8)
2479 manpage ("man 8 hdparm") for that), and it doesn't turn off
2480 VESA-compliant "green" monitors.
2481
2482 This driver does not support the TI 4000M TravelMate and the ACER
2483 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2484 desktop machines also don't have compliant BIOSes, and this driver
2485 may cause those machines to panic during the boot phase.
2486
2487 Generally, if you don't have a battery in your machine, there isn't
2488 much point in using this driver and you should say N. If you get
2489 random kernel OOPSes or reboots that don't seem to be related to
2490 anything, try disabling/enabling this option (or disabling/enabling
2491 APM in your BIOS).
2492
2493 Some other things you should try when experiencing seemingly random,
2494 "weird" problems:
2495
2496 1) make sure that you have enough swap space and that it is
2497 enabled.
2498 2) pass the "no-hlt" option to the kernel
2499 3) switch on floating point emulation in the kernel and pass
2500 the "no387" option to the kernel
2501 4) pass the "floppy=nodma" option to the kernel
2502 5) pass the "mem=4M" option to the kernel (thereby disabling
2503 all but the first 4 MB of RAM)
2504 6) make sure that the CPU is not over clocked.
2505 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2506 8) disable the cache from your BIOS settings
2507 9) install a fan for the video card or exchange video RAM
2508 10) install a better fan for the CPU
2509 11) exchange RAM chips
2510 12) exchange the motherboard.
2511
2512 To compile this driver as a module, choose M here: the
2513 module will be called apm.
2514
2515if APM
2516
2517config APM_IGNORE_USER_SUSPEND
2518 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002519 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002520 This option will ignore USER SUSPEND requests. On machines with a
2521 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2522 series notebooks, it is necessary to say Y because of a BIOS bug.
2523
2524config APM_DO_ENABLE
2525 bool "Enable PM at boot time"
2526 ---help---
2527 Enable APM features at boot time. From page 36 of the APM BIOS
2528 specification: "When disabled, the APM BIOS does not automatically
2529 power manage devices, enter the Standby State, enter the Suspend
2530 State, or take power saving steps in response to CPU Idle calls."
2531 This driver will make CPU Idle calls when Linux is idle (unless this
2532 feature is turned off -- see "Do CPU IDLE calls", below). This
2533 should always save battery power, but more complicated APM features
2534 will be dependent on your BIOS implementation. You may need to turn
2535 this option off if your computer hangs at boot time when using APM
2536 support, or if it beeps continuously instead of suspending. Turn
2537 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2538 T400CDT. This is off by default since most machines do fine without
2539 this feature.
2540
2541config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002542 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002543 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002544 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002545 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2546 On some machines, this can activate improved power savings, such as
2547 a slowed CPU clock rate, when the machine is idle. These idle calls
2548 are made after the idle loop has run for some length of time (e.g.,
2549 333 mS). On some machines, this will cause a hang at boot time or
2550 whenever the CPU becomes idle. (On machines with more than one CPU,
2551 this option does nothing.)
2552
2553config APM_DISPLAY_BLANK
2554 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002555 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002556 Enable console blanking using the APM. Some laptops can use this to
2557 turn off the LCD backlight when the screen blanker of the Linux
2558 virtual console blanks the screen. Note that this is only used by
2559 the virtual console screen blanker, and won't turn off the backlight
2560 when using the X Window system. This also doesn't have anything to
2561 do with your VESA-compliant power-saving monitor. Further, this
2562 option doesn't work for all laptops -- it might not turn off your
2563 backlight at all, or it might print a lot of errors to the console,
2564 especially if you are using gpm.
2565
2566config APM_ALLOW_INTS
2567 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002568 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002569 Normally we disable external interrupts while we are making calls to
2570 the APM BIOS as a measure to lessen the effects of a badly behaving
2571 BIOS implementation. The BIOS should reenable interrupts if it
2572 needs to. Unfortunately, some BIOSes do not -- especially those in
2573 many of the newer IBM Thinkpads. If you experience hangs when you
2574 suspend, try setting this to Y. Otherwise, say N.
2575
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002576endif # APM
2577
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002578source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002579
2580source "drivers/cpuidle/Kconfig"
2581
Andy Henroid27471fd2008-10-09 11:45:22 -07002582source "drivers/idle/Kconfig"
2583
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002584endmenu
2585
2586
2587menu "Bus options (PCI etc.)"
2588
2589config PCI
Ingo Molnar1ac97012008-05-19 14:10:14 +02002590 bool "PCI support"
Adrian Bunk1c858082008-01-30 13:32:32 +01002591 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002592 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002593 Find out whether you have a PCI motherboard. PCI is the name of a
2594 bus system, i.e. the way the CPU talks to the other stuff inside
2595 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2596 VESA. If you have PCI, say Y, otherwise N.
2597
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002598choice
2599 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002600 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002601 default PCI_GOANY
2602 ---help---
2603 On PCI systems, the BIOS can be used to detect the PCI devices and
2604 determine their configuration. However, some old PCI motherboards
2605 have BIOS bugs and may crash if this is done. Also, some embedded
2606 PCI-based systems don't have any BIOS at all. Linux can also try to
2607 detect the PCI hardware directly without using the BIOS.
2608
2609 With this option, you can specify how Linux should detect the
2610 PCI devices. If you choose "BIOS", the BIOS will be used,
2611 if you choose "Direct", the BIOS won't be used, and if you
2612 choose "MMConfig", then PCI Express MMCONFIG will be used.
2613 If you choose "Any", the kernel will try MMCONFIG, then the
2614 direct access method and falls back to the BIOS if that doesn't
2615 work. If unsure, go with the default, which is "Any".
2616
2617config PCI_GOBIOS
2618 bool "BIOS"
2619
2620config PCI_GOMMCONFIG
2621 bool "MMConfig"
2622
2623config PCI_GODIRECT
2624 bool "Direct"
2625
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002626config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002627 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002628 depends on OLPC
2629
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002630config PCI_GOANY
2631 bool "Any"
2632
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002633endchoice
2634
2635config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002636 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002637 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002638
2639# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2640config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002641 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002642 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002643
2644config PCI_MMCONFIG
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002645 def_bool y
Feng Tang5f0db7a2009-08-14 15:37:50 -04002646 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002647
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002648config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002649 def_bool y
2650 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002651
Alex Nixonb5401a92010-03-18 16:31:34 -04002652config PCI_XEN
2653 def_bool y
2654 depends on PCI && XEN
2655 select SWIOTLB_XEN
2656
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002657config PCI_DOMAINS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002658 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002659 depends on PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002660
2661config PCI_MMCONFIG
2662 bool "Support mmconfig PCI config space access"
2663 depends on X86_64 && PCI && ACPI
2664
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002665config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002666 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002667 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002668 help
2669 Read the PCI windows out of the CNB20LE host bridge. This allows
2670 PCI hotplug to work on systems with the CNB20LE chipset which do
2671 not have ACPI.
2672
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002673 There's no public spec for this chipset, and this functionality
2674 is known to be incomplete.
2675
2676 You should say N unless you know you need this.
2677
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002678source "drivers/pci/Kconfig"
2679
William Breathitt Gray3a495512016-05-27 18:08:27 -04002680config ISA_BUS
2681 bool "ISA-style bus support on modern systems" if EXPERT
2682 select ISA_BUS_API
2683 help
2684 Enables ISA-style drivers on modern systems. This is necessary to
2685 support PC/104 devices on X86_64 platforms.
2686
2687 If unsure, say N.
2688
David Rientjes1c00f012011-03-22 16:34:59 -07002689# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002690config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002691 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2692 default y
2693 help
2694 Enables ISA-style DMA support for devices requiring such controllers.
2695 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002696
Linus Torvalds51e68d02016-05-21 10:25:19 -07002697if X86_32
2698
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002699config ISA
2700 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002701 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002702 Find out whether you have ISA slots on your motherboard. ISA is the
2703 name of a bus system, i.e. the way the CPU talks to the other stuff
2704 inside your box. Other bus systems are PCI, EISA, MicroChannel
2705 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2706 newer boards don't support it. If you have ISA, say Y, otherwise N.
2707
2708config EISA
2709 bool "EISA support"
2710 depends on ISA
2711 ---help---
2712 The Extended Industry Standard Architecture (EISA) bus was
2713 developed as an open alternative to the IBM MicroChannel bus.
2714
2715 The EISA bus provided some of the features of the IBM MicroChannel
2716 bus while maintaining backward compatibility with cards made for
2717 the older ISA bus. The EISA bus saw limited use between 1988 and
2718 1995 when it was made obsolete by the PCI bus.
2719
2720 Say Y here if you are building a kernel for an EISA-based machine.
2721
2722 Otherwise, say N.
2723
2724source "drivers/eisa/Kconfig"
2725
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002726config SCx200
2727 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002728 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002729 This provides basic support for National Semiconductor's
2730 (now AMD's) Geode processors. The driver probes for the
2731 PCI-IDs of several on-chip devices, so its a good dependency
2732 for other scx200_* drivers.
2733
2734 If compiled as a module, the driver is named scx200.
2735
2736config SCx200HR_TIMER
2737 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002738 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002739 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002740 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002741 This driver provides a clocksource built upon the on-chip
2742 27MHz high-resolution timer. Its also a workaround for
2743 NSC Geode SC-1100's buggy TSC, which loses time when the
2744 processor goes idle (as is done by the scheduler). The
2745 other workaround is idle=poll boot option.
2746
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002747config OLPC
2748 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002749 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002750 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002751 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002752 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002753 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002754 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002755 Add support for detecting the unique features of the OLPC
2756 XO hardware.
2757
Daniel Drakea3128582011-06-25 17:34:10 +01002758config OLPC_XO1_PM
2759 bool "OLPC XO-1 Power Management"
Daniel Drake97c4cb72011-06-25 17:34:11 +01002760 depends on OLPC && MFD_CS5535 && PM_SLEEP
Daniel Drakea3128582011-06-25 17:34:10 +01002761 select MFD_CORE
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002762 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002763 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002764
Daniel Drakecfee9592011-06-25 17:34:17 +01002765config OLPC_XO1_RTC
2766 bool "OLPC XO-1 Real Time Clock"
2767 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2768 ---help---
2769 Add support for the XO-1 real time clock, which can be used as a
2770 programmable wakeup source.
2771
Daniel Drake7feda8e2011-06-25 17:34:12 +01002772config OLPC_XO1_SCI
2773 bool "OLPC XO-1 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002774 depends on OLPC && OLPC_XO1_PM
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002775 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002776 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002777 select GPIO_CS5535
2778 select MFD_CORE
2779 ---help---
2780 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002781 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002782 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002783 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002784 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002785 - AC adapter status updates
2786 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002787
Daniel Drakea0f30f52011-06-25 17:34:18 +01002788config OLPC_XO15_SCI
2789 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002790 depends on OLPC && ACPI
2791 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002792 ---help---
2793 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2794 - EC-driven system wakeups
2795 - AC adapter status updates
2796 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002797
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002798config ALIX
2799 bool "PCEngines ALIX System Support (LED setup)"
2800 select GPIOLIB
2801 ---help---
2802 This option enables system support for the PCEngines ALIX.
2803 At present this just sets up LEDs for GPIO control on
2804 ALIX2/3/6 boards. However, other system specific setup should
2805 get added here.
2806
2807 Note: You must still enable the drivers for GPIO and LED support
2808 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2809
2810 Note: You have to set alix.force=1 for boards with Award BIOS.
2811
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002812config NET5501
2813 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2814 select GPIOLIB
2815 ---help---
2816 This option enables system support for the Soekris Engineering net5501.
2817
Philip A. Prindeville31970592012-01-14 01:45:39 -07002818config GEOS
2819 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2820 select GPIOLIB
2821 depends on DMI
2822 ---help---
2823 This option enables system support for the Traverse Technologies GEOS.
2824
Vivien Didelot7d029122013-01-04 16:18:14 -05002825config TS5500
2826 bool "Technologic Systems TS-5500 platform support"
2827 depends on MELAN
2828 select CHECK_SIGNATURE
2829 select NEW_LEDS
2830 select LEDS_CLASS
2831 ---help---
2832 This option enables system support for the Technologic Systems TS-5500.
2833
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002834endif # X86_32
2835
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002836config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002837 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002838 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002839
2840source "drivers/pcmcia/Kconfig"
2841
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002842config RAPIDIO
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002843 tristate "RapidIO support"
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002844 depends on PCI
2845 default n
2846 help
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002847 If enabled this option will include drivers and the core
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002848 infrastructure code to support RapidIO interconnect devices.
2849
2850source "drivers/rapidio/Kconfig"
2851
David Herrmanne3263ab2013-08-02 14:05:22 +02002852config X86_SYSFB
2853 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2854 help
2855 Firmwares often provide initial graphics framebuffers so the BIOS,
2856 bootloader or kernel can show basic video-output during boot for
2857 user-guidance and debugging. Historically, x86 used the VESA BIOS
2858 Extensions and EFI-framebuffers for this, which are mostly limited
2859 to x86.
2860 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2861 framebuffers so the new generic system-framebuffer drivers can be
2862 used on x86. If the framebuffer is not compatible with the generic
2863 modes, it is adverticed as fallback platform framebuffer so legacy
2864 drivers like efifb, vesafb and uvesafb can pick it up.
2865 If this option is not selected, all system framebuffers are always
2866 marked as fallback platform framebuffers as usual.
2867
2868 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2869 not be able to pick up generic system framebuffers if this option
2870 is selected. You are highly encouraged to enable simplefb as
2871 replacement if you select this option. simplefb can correctly deal
2872 with generic system framebuffers. But you should still keep vesafb
2873 and others enabled as fallback if a system framebuffer is
2874 incompatible with simplefb.
2875
2876 If unsure, say Y.
2877
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002878endmenu
2879
2880
2881menu "Executable file formats / Emulations"
2882
2883source "fs/Kconfig.binfmt"
2884
2885config IA32_EMULATION
2886 bool "IA32 Emulation"
2887 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002888 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002889 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002890 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002891 select COMPAT_OLD_SIGACTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002892 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002893 Include code to run legacy 32-bit programs under a
2894 64-bit kernel. You should likely turn this on, unless you're
2895 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002896
2897config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002898 tristate "IA32 a.out support"
2899 depends on IA32_EMULATION
2900 ---help---
2901 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002902
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002903config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002904 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002905 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002906 ---help---
2907 Include code to run binaries for the x32 native 32-bit ABI
2908 for 64-bit processors. An x32 process gets access to the
2909 full 64-bit register file and wide data path while leaving
2910 pointers at 32 bits for smaller memory footprint.
2911
2912 You will need a recent binutils (2.22 or later) with
2913 elf32_x86_64 support enabled to compile a kernel with this
2914 option set.
2915
Ingo Molnar953fee12016-11-15 10:22:52 +01002916config COMPAT_32
2917 def_bool y
2918 depends on IA32_EMULATION || X86_32
2919 select HAVE_UID16
2920 select OLD_SIGSUSPEND3
2921
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002922config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002923 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002924 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002925
Jan Beulich3120e252012-09-10 12:41:45 +01002926if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002927config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002928 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002929
2930config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002931 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002932 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002933endif
David Howellsee009e4a02011-03-07 15:06:20 +00002934
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002935endmenu
2936
2937
Keith Packarde5beae12008-11-03 18:21:45 +01002938config HAVE_ATOMIC_IOMAP
2939 def_bool y
2940 depends on X86_32
2941
Alessandro Rubini4692d772012-04-04 19:39:58 +02002942config X86_DEV_DMA_OPS
2943 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002944 depends on X86_64 || STA2X11
Alessandro Rubini4692d772012-04-04 19:39:58 +02002945
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002946config X86_DMA_REMAP
2947 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002948 depends on STA2X11
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002949
Kirill A. Shutemove5855132017-06-06 14:31:20 +03002950config HAVE_GENERIC_GUP
2951 def_bool y
2952
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002953source "net/Kconfig"
2954
2955source "drivers/Kconfig"
2956
2957source "drivers/firmware/Kconfig"
2958
2959source "fs/Kconfig"
2960
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002961source "arch/x86/Kconfig.debug"
2962
2963source "security/Kconfig"
2964
2965source "crypto/Kconfig"
2966
Avi Kivityedf88412007-12-16 11:02:48 +02002967source "arch/x86/kvm/Kconfig"
2968
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002969source "lib/Kconfig"