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Greg Kroah-Hartmanb2441312017-11-01 15:07:57 +01001# SPDX-License-Identifier: GPL-2.0
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01002# Select 32 or 64 bit
3config 64BIT
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
Christoph Hellwigea8c64a2018-01-10 16:21:13 +010057 select ARCH_HAS_PHYS_TO_DMA
Mathieu Desnoyers10bcc802018-01-29 15:20:18 -050058 select ARCH_HAS_MEMBARRIER_SYNC_CORE
Ingo Molnarc763ea22016-11-15 10:26:39 +010059 select ARCH_HAS_PMEM_API if X86_64
Kees Cook39208aa2017-09-02 13:09:46 -070060 select ARCH_HAS_REFCOUNT
Dan Williams0aed55a2017-05-29 12:22:50 -070061 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Daniel Borkmannd2852a22017-02-21 16:09:33 +010062 select ARCH_HAS_SET_MEMORY
Ingo Molnar6471b822015-06-03 10:00:13 +020063 select ARCH_HAS_SG_CHAIN
Laura Abbottad21fc42017-02-06 16:31:57 -080064 select ARCH_HAS_STRICT_KERNEL_RWX
65 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050066 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Andrey Ryabininc6d30852016-01-20 15:00:55 -080067 select ARCH_HAS_UBSAN_SANITIZE_ALL
Oliver O'Halloran65f7d042017-06-28 11:32:31 +100068 select ARCH_HAS_ZONE_DEVICE if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020069 select ARCH_HAVE_NMI_SAFE_CMPXCHG
70 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040071 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080072 select ARCH_MIGHT_HAVE_PC_SERIO
Ingo Molnar6471b822015-06-03 10:00:13 +020073 select ARCH_SUPPORTS_ATOMIC_RMW
Ingo Molnar6471b822015-06-03 10:00:13 +020074 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
75 select ARCH_USE_BUILTIN_BSWAP
Ingo Molnar6471b822015-06-03 10:00:13 +020076 select ARCH_USE_QUEUED_RWLOCKS
77 select ARCH_USE_QUEUED_SPINLOCKS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -070078 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Ingo Molnarc763ea22016-11-15 10:26:39 +010079 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Huang Ying38d8b4e2017-07-06 15:37:18 -070080 select ARCH_WANTS_THP_SWAP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020081 select BUILDTIME_EXTABLE_SORT
82 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +020083 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
84 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +020085 select DCACHE_WORD_ACCESS
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
694 select X86_DEV_DMA_OPS
695 select X86_DMA_REMAP
696 select SWIOTLB
697 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200698 select GPIOLIB
Alessandro Rubini83125a32012-04-04 19:40:21 +0200699 default n
700 ---help---
701 This adds support for boards based on the STA2X11 IO-Hub,
702 a.k.a. "ConneXt". The chip is used in place of the standard
703 PC chipset, so all "standard" peripherals are missing. If this
704 option is selected the kernel will still be able to boot on
705 standard PC machines.
706
Shérab82148d12010-09-25 06:06:57 +0200707config X86_32_IRIS
708 tristate "Eurobraille/Iris poweroff module"
709 depends on X86_32
710 ---help---
711 The Iris machines from EuroBraille do not have APM or ACPI support
712 to shut themselves down properly. A special I/O sequence is
713 needed to do so, which is what this module does at
714 kernel shutdown.
715
716 This is only for Iris machines from EuroBraille.
717
718 If unused, say N.
719
Ingo Molnarae1e9132008-11-11 09:05:16 +0100720config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100721 def_bool y
722 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800723 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100724 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100725 Calculate simpler /proc/<PID>/wchan values. If this option
726 is disabled then wchan values will recurse back to the
727 caller function. This provides more accurate wchan values,
728 at the expense of slightly more scheduling overhead.
729
730 If in doubt, say "Y".
731
Borislav Petkov6276a072013-03-04 21:20:21 +0100732menuconfig HYPERVISOR_GUEST
733 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100734 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100735 Say Y here to enable options for running Linux under various hyper-
736 visors. This option enables basic hypervisor detection and platform
737 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100738
Borislav Petkov6276a072013-03-04 21:20:21 +0100739 If you say N, all options in this submenu will be skipped and
740 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100741
Borislav Petkov6276a072013-03-04 21:20:21 +0100742if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100743
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100744config PARAVIRT
745 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100746 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100747 This changes the kernel so it can modify itself when it is run
748 under a hypervisor, potentially improving performance significantly
749 over full virtualization. However, when run without a hypervisor
750 the kernel is theoretically slower and slightly larger.
751
Borislav Petkov6276a072013-03-04 21:20:21 +0100752config PARAVIRT_DEBUG
753 bool "paravirt-ops debugging"
754 depends on PARAVIRT && DEBUG_KERNEL
755 ---help---
756 Enable to debug paravirt_ops internals. Specifically, BUG if
757 a paravirt_op is missing when it is called.
758
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700759config PARAVIRT_SPINLOCKS
760 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700761 depends on PARAVIRT && SMP
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700762 ---help---
763 Paravirtualized spinlocks allow a pvops backend to replace the
764 spinlock implementation with something virtualization-friendly
765 (for example, block the virtual CPU rather than spinning).
766
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530767 It has a minimal impact on native kernels and gives a nice performance
768 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700769
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530770 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700771
Waiman Long45e898b2015-11-09 19:09:25 -0500772config QUEUED_LOCK_STAT
773 bool "Paravirt queued spinlock statistics"
Peter Zijlstracfd89832016-05-18 20:43:02 +0200774 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
Waiman Long45e898b2015-11-09 19:09:25 -0500775 ---help---
776 Enable the collection of statistical data on the slowpath
777 behavior of paravirtualized queued spinlocks and report
778 them on debugfs.
779
Borislav Petkov6276a072013-03-04 21:20:21 +0100780source "arch/x86/xen/Kconfig"
781
782config KVM_GUEST
783 bool "KVM Guest support (including kvmclock)"
784 depends on PARAVIRT
785 select PARAVIRT_CLOCK
786 default y
787 ---help---
788 This option enables various optimizations for running under the KVM
789 hypervisor. It includes a paravirtualized clock, so that instead
790 of relying on a PIT (or probably other) emulation by the
791 underlying device model, the host provides the guest with
792 timing infrastructure such as time of day, and system time
793
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530794config KVM_DEBUG_FS
795 bool "Enable debug information for KVM Guests in debugfs"
796 depends on KVM_GUEST && DEBUG_FS
797 default n
798 ---help---
799 This option enables collection of various statistics for KVM guest.
800 Statistics are displayed in debugfs filesystem. Enabling this option
801 may incur significant overhead.
802
Borislav Petkov6276a072013-03-04 21:20:21 +0100803config PARAVIRT_TIME_ACCOUNTING
804 bool "Paravirtual steal time accounting"
805 depends on PARAVIRT
806 default n
807 ---help---
808 Select this option to enable fine granularity task steal time
809 accounting. Time spent executing other tasks in parallel with
810 the current vCPU is discounted from the vCPU power. To account for
811 that, there can be a small performance impact.
812
813 If in doubt, say N here.
814
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200815config PARAVIRT_CLOCK
816 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200817
Jan Kiszka4a362602017-11-27 09:11:46 +0100818config JAILHOUSE_GUEST
819 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100820 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100821 select X86_PM_TIMER
Jan Kiszka4a362602017-11-27 09:11:46 +0100822 ---help---
823 This option allows to run Linux as guest in a Jailhouse non-root
824 cell. You can leave this option disabled if you only want to start
825 Jailhouse and run Linux afterwards in the root cell.
826
Borislav Petkov6276a072013-03-04 21:20:21 +0100827endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400828
Yinghai Lu08677212010-02-10 01:20:20 -0800829config NO_BOOTMEM
Yinghai Lu774ea0b2010-08-25 13:39:18 -0700830 def_bool y
Yinghai Lu08677212010-02-10 01:20:20 -0800831
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100832source "arch/x86/Kconfig.cpu"
833
834config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100835 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100836 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100837 ---help---
838 Use the IA-PC HPET (High Precision Event Timer) to manage
839 time in preference to the PIT and RTC, if a HPET is
840 present.
841 HPET is the next generation timer replacing legacy 8254s.
842 The HPET provides a stable time base on SMP
843 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200844 as it is off-chip. The interface used is documented
845 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100846
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100847 You can safely choose Y here. However, HPET will only be
848 activated if the platform and the BIOS support this feature.
849 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100850
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100851 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100852
853config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100854 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800855 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100856
Jacob Panbb24c472009-09-02 07:37:17 -0700857config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000858 def_bool y if X86_INTEL_MID
859 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100860 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000861 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700862 help
863 APB timer is the replacement for 8254, HPET on X86 MID platforms.
864 The APBT provides a stable time base on SMP
865 systems, unlike the TSC, but it is more expensive to access,
866 as it is off-chip. APB timers are always running regardless of CPU
867 C states, they are used as per CPU clockevent device when possible.
868
David Rientjes6a108a12011-01-20 14:44:16 -0800869# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100870# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700871config DMI
872 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800873 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800874 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100875 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700876 Enabled scanning of DMI to identify machine quirks. Say Y
877 here unless you have verified that your setup is not
878 affected by entries in the DMI blacklist. Required by PNP
879 BIOS code.
880
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100881config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700882 bool "Old AMD GART IOMMU support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100883 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200884 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100885 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200886 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
887 GART based hardware IOMMUs.
888
889 The GART supports full DMA access for devices with 32-bit access
890 limitations, on systems with more than 3 GB. This is usually needed
891 for USB, sound, many IDE/SATA chipsets and some other devices.
892
893 Newer systems typically have a modern AMD IOMMU, supported via
894 the CONFIG_AMD_IOMMU=y config option.
895
896 In normal configurations this driver is only active when needed:
897 there's more than 3 GB of memory and the system contains a
898 32-bit limited device.
899
900 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100901
902config CALGARY_IOMMU
903 bool "IBM Calgary IOMMU support"
904 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700905 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100906 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100907 Support for hardware IOMMUs in IBM's xSeries x366 and x460
908 systems. Needed to run systems with more than 3GB of memory
909 properly with 32-bit PCI devices that do not support DAC
910 (Double Address Cycle). Calgary also supports bus level
911 isolation, where all DMAs pass through the IOMMU. This
912 prevents them from going anywhere except their intended
913 destination. This catches hard-to-find kernel bugs and
914 mis-behaving drivers and devices that do not use the DMA-API
915 properly to set up their DMA buffers. The IOMMU can be
916 turned off at boot time with the iommu=off parameter.
917 Normally the kernel will make the right choice by itself.
918 If unsure, say Y.
919
920config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100921 def_bool y
922 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100923 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100924 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100925 Should Calgary be enabled by default? if you choose 'y', Calgary
926 will be used (if it exists). If you choose 'n', Calgary will not be
927 used even if it exists. If you choose 'n' and would like to use
928 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
929 If unsure, say Y.
930
931# need this always selected by IOMMU for the VIA workaround
932config SWIOTLB
Joerg Roedela1afd012008-11-18 12:44:21 +0100933 def_bool y if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100934 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100935 Support for software bounce buffers used on x86-64 systems
Joe Millenbach4454d322012-09-02 17:38:20 -0700936 which don't have a hardware IOMMU. Using this PCI devices
937 which can only access 32-bits of memory can be used on systems
938 with more than 3 GB of memory.
939 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100940
FUJITA Tomonoria8522502008-04-29 00:59:36 -0700941config IOMMU_HELPER
Jan Beulich3120e252012-09-10 12:41:45 +0100942 def_bool y
943 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
Linus Torvaldsd25e26b2008-08-25 14:15:38 -0700944
Mike Travis1184dc22008-05-12 21:21:12 +0200945config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200946 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700947 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800948 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100949 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200950 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200951 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100952
Ingo Molnaraec64872018-02-10 12:36:29 +0100953#
954# The maximum number of CPUs supported:
955#
956# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
957# and which can be configured interactively in the
958# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
959#
960# The ranges are different on 32-bit and 64-bit kernels, depending on
961# hardware capabilities and scalability features of the kernel.
962#
963# ( If MAXSMP is enabled we just use the highest possible value and disable
964# interactive configuration. )
965#
966
967config NR_CPUS_RANGE_BEGIN
968 int
969 default NR_CPUS_RANGE_END if MAXSMP
970 default 1 if !SMP
971 default 2
972
973config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800974 int
975 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100976 default 64 if SMP && X86_BIGSMP
977 default 8 if SMP && !X86_BIGSMP
978 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800979
Ingo Molnaraec64872018-02-10 12:36:29 +0100980config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800981 int
982 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100983 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
984 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
985 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800986
Ingo Molnaraec64872018-02-10 12:36:29 +0100987config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800988 int
989 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100990 default 32 if X86_BIGSMP
991 default 8 if SMP
992 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800993
Ingo Molnaraec64872018-02-10 12:36:29 +0100994config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800995 int
996 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100997 default 8192 if MAXSMP
998 default 64 if SMP
999 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -08001000
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001001config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -08001002 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +01001003 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
1004 default NR_CPUS_DEFAULT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001005 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001006 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -05001007 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +03001008 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001009 minimum value which makes sense is 2.
1010
Ingo Molnaraec64872018-02-10 12:36:29 +01001011 This is purely to save memory: each supported CPU adds about 8KB
1012 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001013
1014config SCHED_SMT
1015 bool "SMT (Hyperthreading) scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001016 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001017 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001018 SMT scheduler support improves the CPU scheduler's decision making
1019 when dealing with Intel Pentium 4 chips with HyperThreading at a
1020 cost of slightly increased overhead in some places. If unsure say
1021 N here.
1022
1023config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001024 def_bool y
1025 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001026 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001027 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001028 Multi-core scheduler support improves the CPU scheduler's decision
1029 making when dealing with multi-core CPU chips at a cost of slightly
1030 increased overhead in some places. If unsure say N here.
1031
Tim Chende966cf2016-11-29 10:43:27 -08001032config SCHED_MC_PRIO
1033 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001034 depends on SCHED_MC && CPU_SUP_INTEL
1035 select X86_INTEL_PSTATE
1036 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001037 default y
Tim Chen5e76b2a2016-11-22 12:23:55 -08001038 ---help---
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001039 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1040 core ordering determined at manufacturing time, which allows
1041 certain cores to reach higher turbo frequencies (when running
1042 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001043
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001044 Enabling this kernel feature teaches the scheduler about
1045 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1046 scheduler's CPU selection logic accordingly, so that higher
1047 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001048
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001049 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001050
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001051 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001052
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001053source "kernel/Kconfig.preempt"
1054
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001055config UP_LATE_INIT
1056 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +01001057 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001058
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001059config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001060 bool "Local APIC support on uniprocessors" if !PCI_MSI
1061 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001062 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001063 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001064 A local APIC (Advanced Programmable Interrupt Controller) is an
1065 integrated interrupt controller in the CPU. If you have a single-CPU
1066 system which has a processor with a local APIC, you can say Y here to
1067 enable and use it. If you say Y here even though your machine doesn't
1068 have a local APIC, then the kernel will still run with no slowdown at
1069 all. The local APIC supports CPU-generated self-interrupts (timer,
1070 performance counters), and the NMI watchdog which detects hard
1071 lockups.
1072
1073config X86_UP_IOAPIC
1074 bool "IO-APIC support on uniprocessors"
1075 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001076 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001077 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1078 SMP-capable replacement for PC-style interrupt controllers. Most
1079 SMP systems and many recent uniprocessor systems have one.
1080
1081 If you have a single-CPU system with an IO-APIC, you can say Y here
1082 to use it. If you say Y here even though your machine doesn't have
1083 an IO-APIC, then the kernel will still run with no slowdown at all.
1084
1085config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001086 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001087 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001088 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001089 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001090
1091config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001092 def_bool y
1093 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001094
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001095config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1096 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001097 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001098 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001099 This option enables a workaround that fixes a source of
1100 spurious interrupts. This is recommended when threaded
1101 interrupt handling is used on systems where the generation of
1102 superfluous "boot interrupts" cannot be disabled.
1103
1104 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1105 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1106 kernel does during interrupt handling). On chipsets where this
1107 boot IRQ generation cannot be disabled, this workaround keeps
1108 the original IRQ line masked so that only the equivalent "boot
1109 IRQ" is delivered to the CPUs. The workaround also tells the
1110 kernel to set up the IRQ handler on the boot IRQ line. In this
1111 way only one interrupt is delivered to the kernel. Otherwise
1112 the spurious second interrupt may cause the kernel to bring
1113 down (vital) interrupt lines.
1114
1115 Only affects "broken" chipsets. Interrupt sharing may be
1116 increased on these systems.
1117
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001118config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001119 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001120 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001121 default y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001122 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +02001123 Machine Check support allows the processor to notify the
1124 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001125 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001126 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001127
Tony Luck5de97c92017-03-27 11:33:03 +02001128config X86_MCELOG_LEGACY
1129 bool "Support for deprecated /dev/mcelog character device"
1130 depends on X86_MCE
1131 ---help---
1132 Enable support for /dev/mcelog which is needed by the old mcelog
1133 userspace logging daemon. Consider switching to the new generation
1134 rasdaemon solution.
1135
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001136config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001137 def_bool y
1138 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001139 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001140 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001141 Additional support for intel specific MCE features such as
1142 the thermal monitor.
1143
1144config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001145 def_bool y
1146 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001147 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001148 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001149 Additional support for AMD specific MCE features such as
1150 the DRAM Error Threshold.
1151
Andi Kleen4efc0672009-04-28 19:07:31 +02001152config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001153 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001154 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001155 ---help---
1156 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001157 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001158 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001159
Andi Kleenb2762682009-02-12 13:49:31 +01001160config X86_MCE_THRESHOLD
1161 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001162 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001163
Andi Kleenea149b32009-04-29 19:31:00 +02001164config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001165 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001166 tristate "Machine check injector support"
1167 ---help---
1168 Provide support for injecting machine checks for testing purposes.
1169 If you don't know what a machine check is and you don't do kernel
1170 QA it is safe to say n.
1171
Andi Kleen4efc0672009-04-28 19:07:31 +02001172config X86_THERMAL_VECTOR
1173 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001174 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001175
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001176source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001177
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001178config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001179 bool "Legacy VM86 support"
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001180 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001181 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001182 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001183 This option allows user programs to put the CPU into V8086
1184 mode, which is an 80286-era approximation of 16-bit real mode.
1185
1186 Some very old versions of X and/or vbetool require this option
1187 for user mode setting. Similarly, DOSEMU will use it if
1188 available to accelerate real mode DOS programs. However, any
1189 recent version of DOSEMU, X, or vbetool should be fully
1190 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001191 fall back to software emulation. Nevertheless, if you are using
1192 a 16-bit DOS program where 16-bit performance matters, vm86
1193 mode might be faster than emulation and you might want to
1194 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001195
Ingo Molnar1e642812015-09-05 08:58:10 +02001196 Note that any app that works on a 64-bit kernel is unlikely to
1197 need this option, as 64-bit kernels don't, and can't, support
1198 V8086 mode. This option is also unrelated to 16-bit protected
1199 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001200
Ingo Molnar1e642812015-09-05 08:58:10 +02001201 Enabling this option increases the complexity of the kernel
1202 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001203
Ingo Molnar1e642812015-09-05 08:58:10 +02001204 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001205
1206config VM86
1207 bool
1208 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001209
1210config X86_16BIT
1211 bool "Enable support for 16-bit segments" if EXPERT
1212 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001213 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001214 ---help---
1215 This option is required by programs like Wine to run 16-bit
1216 protected mode legacy code on x86 processors. Disabling
1217 this option saves about 300 bytes on i386, or around 6K text
1218 plus 16K runtime memory on x86-64,
1219
1220config X86_ESPFIX32
1221 def_bool y
1222 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001223
H. Peter Anvin197725d2014-05-04 10:00:49 -07001224config X86_ESPFIX64
1225 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001226 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001227
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001228config X86_VSYSCALL_EMULATION
1229 bool "Enable vsyscall emulation" if EXPERT
1230 default y
1231 depends on X86_64
1232 ---help---
1233 This enables emulation of the legacy vsyscall page. Disabling
1234 it is roughly equivalent to booting with vsyscall=none, except
1235 that it will also disable the helpful warning if a program
1236 tries to use a vsyscall. With this option set to N, offending
1237 programs will just segfault, citing addresses of the form
1238 0xffffffffff600?00.
1239
1240 This option is required by many programs built before 2013, and
1241 care should be used even with newer programs if set to N.
1242
1243 Disabling this option saves about 7K of kernel size and
1244 possibly 4K of additional runtime pagetable memory.
1245
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001246config TOSHIBA
1247 tristate "Toshiba Laptop support"
1248 depends on X86_32
1249 ---help---
1250 This adds a driver to safely access the System Management Mode of
1251 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1252 not work on models with a Phoenix BIOS. The System Management Mode
1253 is used to set the BIOS and power saving options on Toshiba portables.
1254
1255 For information on utilities to make use of this driver see the
1256 Toshiba Linux utilities web site at:
1257 <http://www.buzzard.org.uk/toshiba/>.
1258
1259 Say Y if you intend to run this kernel on a Toshiba portable.
1260 Say N otherwise.
1261
1262config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001263 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001264 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001265 select SENSORS_DELL_SMM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001266 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001267 This option enables legacy /proc/i8k userspace interface in hwmon
1268 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1269 temperature and allows controlling fan speeds of Dell laptops via
1270 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1271 it reports also power and hotkey status. For fan speed control is
1272 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001273
Pali Rohár039ae582015-05-14 13:16:37 +02001274 Say Y if you intend to run this kernel on old Dell laptops or want to
1275 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001276 Say N otherwise.
1277
1278config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001279 bool "Enable X86 board specific fixups for reboot"
1280 depends on X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001281 ---help---
1282 This enables chipset and/or board specific fixups to be done
1283 in order to get reboot to work correctly. This is only needed on
1284 some combinations of hardware and BIOS. The symptom, for which
1285 this config is intended, is when reboot ends with a stalled/hung
1286 system.
1287
1288 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001289 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001290
1291 Say Y if you want to enable the fixup. Currently, it's safe to
1292 enable this option even if you don't need it.
1293 Say N otherwise.
1294
1295config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001296 bool "CPU microcode loading support"
1297 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001298 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001299 select FW_LOADER
1300 ---help---
1301 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001302 Intel and AMD processors. The Intel support is for the IA32 family,
1303 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1304 AMD support is for families 0x10 and later. You will obviously need
1305 the actual microcode binary data itself which is not shipped with
1306 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001307
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001308 The preferred method to load microcode from a detached initrd is described
1309 in Documentation/x86/early-microcode.txt. For that you need to enable
1310 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1311 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001312
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001313 In addition, you can build the microcode into the kernel. For that you
1314 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1315 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001316
Peter Oruba8d86f392008-07-28 18:44:21 +02001317config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001318 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001319 depends on MICROCODE
1320 default MICROCODE
1321 select FW_LOADER
1322 ---help---
1323 This options enables microcode patch loading support for Intel
1324 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001325
Alanb8989db2014-01-20 18:01:56 +00001326 For the current Intel microcode data package go to
1327 <https://downloadcenter.intel.com> and search for
1328 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001329
Peter Oruba80cc9f12008-07-28 18:44:22 +02001330config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001331 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001332 depends on MICROCODE
1333 select FW_LOADER
1334 ---help---
1335 If you select this option, microcode patch loading support for AMD
1336 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001337
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001338config MICROCODE_OLD_INTERFACE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001339 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001340 depends on MICROCODE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001341
1342config X86_MSR
1343 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001344 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001345 This device gives privileged processes access to the x86
1346 Model-Specific Registers (MSRs). It is a character device with
1347 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1348 MSR accesses are directed to a specific CPU on multi-processor
1349 systems.
1350
1351config X86_CPUID
1352 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001353 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001354 This device gives processes access to the x86 CPUID instruction to
1355 be executed on a specific processor. It is a character device
1356 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1357 /dev/cpu/31/cpuid.
1358
1359choice
1360 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001361 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001362 depends on X86_32
1363
1364config NOHIGHMEM
1365 bool "off"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001366 ---help---
1367 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1368 However, the address space of 32-bit x86 processors is only 4
1369 Gigabytes large. That means that, if you have a large amount of
1370 physical memory, not all of it can be "permanently mapped" by the
1371 kernel. The physical memory that's not permanently mapped is called
1372 "high memory".
1373
1374 If you are compiling a kernel which will never run on a machine with
1375 more than 1 Gigabyte total physical RAM, answer "off" here (default
1376 choice and suitable for most users). This will result in a "3GB/1GB"
1377 split: 3GB are mapped so that each process sees a 3GB virtual memory
1378 space and the remaining part of the 4GB virtual memory space is used
1379 by the kernel to permanently map as much physical memory as
1380 possible.
1381
1382 If the machine has between 1 and 4 Gigabytes physical RAM, then
1383 answer "4GB" here.
1384
1385 If more than 4 Gigabytes is used then answer "64GB" here. This
1386 selection turns Intel PAE (Physical Address Extension) mode on.
1387 PAE implements 3-level paging on IA32 processors. PAE is fully
1388 supported by Linux, PAE mode is implemented on all recent Intel
1389 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1390 then the kernel will not boot on CPUs that don't support PAE!
1391
1392 The actual amount of total physical memory will either be
1393 auto detected or can be forced by using a kernel command line option
1394 such as "mem=256M". (Try "man bootparam" or see the documentation of
1395 your boot loader (lilo or loadlin) about how to pass options to the
1396 kernel at boot time.)
1397
1398 If unsure, say "off".
1399
1400config HIGHMEM4G
1401 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001402 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001403 Select this if you have a 32-bit processor and between 1 and 4
1404 gigabytes of physical RAM.
1405
1406config HIGHMEM64G
1407 bool "64GB"
Matthew Whitehead69b8d3f2018-02-15 11:54:55 -05001408 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001409 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001410 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001411 Select this if you have a 32-bit processor and more than 4
1412 gigabytes of physical RAM.
1413
1414endchoice
1415
1416choice
David Rientjes6a108a12011-01-20 14:44:16 -08001417 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001418 default VMSPLIT_3G
1419 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001420 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001421 Select the desired split between kernel and user memory.
1422
1423 If the address range available to the kernel is less than the
1424 physical memory installed, the remaining memory will be available
1425 as "high memory". Accessing high memory is a little more costly
1426 than low memory, as it needs to be mapped into the kernel first.
1427 Note that increasing the kernel address space limits the range
1428 available to user programs, making the address space there
1429 tighter. Selecting anything other than the default 3G/1G split
1430 will also likely make your kernel incompatible with binary-only
1431 kernel modules.
1432
1433 If you are not absolutely sure what you are doing, leave this
1434 option alone!
1435
1436 config VMSPLIT_3G
1437 bool "3G/1G user/kernel split"
1438 config VMSPLIT_3G_OPT
1439 depends on !X86_PAE
1440 bool "3G/1G user/kernel split (for full 1G low memory)"
1441 config VMSPLIT_2G
1442 bool "2G/2G user/kernel split"
1443 config VMSPLIT_2G_OPT
1444 depends on !X86_PAE
1445 bool "2G/2G user/kernel split (for full 2G low memory)"
1446 config VMSPLIT_1G
1447 bool "1G/3G user/kernel split"
1448endchoice
1449
1450config PAGE_OFFSET
1451 hex
1452 default 0xB0000000 if VMSPLIT_3G_OPT
1453 default 0x80000000 if VMSPLIT_2G
1454 default 0x78000000 if VMSPLIT_2G_OPT
1455 default 0x40000000 if VMSPLIT_1G
1456 default 0xC0000000
1457 depends on X86_32
1458
1459config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001460 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001461 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001462
1463config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001464 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001465 depends on X86_32 && !HIGHMEM4G
Christian Melki9d99c712015-10-05 17:31:33 +02001466 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001467 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001468 PAE is required for NX support, and furthermore enables
1469 larger swapspace support for non-overcommit purposes. It
1470 has the cost of more pagetable lookup overhead, and also
1471 consumes more pagetable space per process.
1472
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001473config X86_5LEVEL
1474 bool "Enable 5-level page tables support"
1475 depends on X86_64
1476 ---help---
1477 5-level paging enables access to larger address space:
1478 upto 128 PiB of virtual address space and 4 PiB of
1479 physical address space.
1480
1481 It will be supported by future Intel CPUs.
1482
1483 Note: a kernel with this option enabled can only be booted
1484 on machines that support the feature.
1485
1486 See Documentation/x86/x86_64/5level-paging.txt for more
1487 information.
1488
1489 Say N if unsure.
1490
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001491config ARCH_PHYS_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001492 def_bool y
1493 depends on X86_64 || X86_PAE
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001494
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001495config ARCH_DMA_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001496 def_bool y
1497 depends on X86_64 || HIGHMEM64G
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001498
Ingo Molnar10971ab2015-03-05 08:18:23 +01001499config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001500 def_bool y
Levin, Alexander (Sasha Levin)4675ff02017-11-15 17:36:02 -08001501 depends on X86_64 && !DEBUG_PAGEALLOC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001502 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001503 Certain kernel features effectively disable kernel
1504 linear 1 GB mappings (even if the CPU otherwise
1505 supports them), so don't confuse the user by printing
1506 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001507
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001508config ARCH_HAS_MEM_ENCRYPT
1509 def_bool y
1510
1511config AMD_MEM_ENCRYPT
1512 bool "AMD Secure Memory Encryption (SME) support"
1513 depends on X86_64 && CPU_SUP_AMD
1514 ---help---
1515 Say yes to enable support for the encryption of system memory.
1516 This requires an AMD processor that supports Secure Memory
1517 Encryption (SME).
1518
1519config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1520 bool "Activate AMD Secure Memory Encryption (SME) by default"
1521 default y
1522 depends on AMD_MEM_ENCRYPT
1523 ---help---
1524 Say yes to have system memory encrypted by default if running on
1525 an AMD processor that supports Secure Memory Encryption (SME).
1526
1527 If set to Y, then the encryption of system memory can be
1528 deactivated with the mem_encrypt=off command line option.
1529
1530 If set to N, then the encryption of system memory can be
1531 activated with the mem_encrypt=on command line option.
1532
Tom Lendackyf88a68f2017-07-17 16:10:09 -05001533config ARCH_USE_MEMREMAP_PROT
1534 def_bool y
1535 depends on AMD_MEM_ENCRYPT
1536
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001537# Common NUMA Features
1538config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001539 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001540 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001541 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1542 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001543 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001544 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001545
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001546 The kernel will try to allocate memory used by a CPU on the
1547 local memory controller of the CPU and add some more
1548 NUMA awareness to the kernel.
1549
Ingo Molnarc280ea52008-11-08 13:29:45 +01001550 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001551 (or later), AMD Opteron, or EM64T NUMA.
1552
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001553 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001554 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001555
1556 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001557
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001558config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001559 def_bool y
1560 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001561 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001562 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001563 Enable AMD NUMA node topology detection. You should say Y here if
1564 you have a multi processor AMD system. This uses an old method to
1565 read the NUMA configuration directly from the builtin Northbridge
1566 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1567 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001568
1569config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001570 def_bool y
1571 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001572 depends on X86_64 && NUMA && ACPI && PCI
1573 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001574 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001575 Enable ACPI SRAT based node topology detection.
1576
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001577# Some NUMA nodes have memory ranges that span
1578# other nodes. Even though a pfn is valid and
1579# between a node's start and end pfns, it may not
1580# reside on that node. See memmap_init_zone()
1581# for details.
1582config NODES_SPAN_OTHER_NODES
1583 def_bool y
1584 depends on X86_64_ACPI_NUMA
1585
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001586config NUMA_EMU
1587 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001588 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001589 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001590 Enable NUMA emulation. A flat machine will be split
1591 into virtual nodes when booted with "numa=fake=N", where N is the
1592 number of nodes. This is only useful for debugging.
1593
1594config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001595 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001596 range 1 10
1597 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001598 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001599 default "3"
1600 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001601 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001602 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001603 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001604
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001605config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001606 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001607 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001608
1609config NEED_NODE_MEMMAP_SIZE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001610 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001611 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001612
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001613config ARCH_FLATMEM_ENABLE
1614 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001615 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001616
1617config ARCH_DISCONTIGMEM_ENABLE
1618 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001619 depends on NUMA && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001620
1621config ARCH_DISCONTIGMEM_DEFAULT
1622 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001623 depends on NUMA && X86_32
1624
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001625config ARCH_SPARSEMEM_ENABLE
1626 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001627 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001628 select SPARSEMEM_STATIC if X86_32
1629 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1630
Tejun Heo3b166512011-04-01 11:15:12 +02001631config ARCH_SPARSEMEM_DEFAULT
1632 def_bool y
1633 depends on X86_64
1634
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001635config ARCH_SELECT_MEMORY_MODEL
1636 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001637 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001638
1639config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001640 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001641 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001642 help
1643 This option enables a sysfs memory/probe interface for testing.
1644 See Documentation/memory-hotplug.txt for more information.
1645 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001646
Tejun Heo3b166512011-04-01 11:15:12 +02001647config ARCH_PROC_KCORE_TEXT
1648 def_bool y
1649 depends on X86_64 && PROC_KCORE
1650
Avi Kivitya29815a2010-01-10 16:28:09 +02001651config ILLEGAL_POINTER_VALUE
1652 hex
1653 default 0 if X86_32
1654 default 0xdead000000000000 if X86_64
1655
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001656source "mm/Kconfig"
1657
Dan Williams7a678322015-08-19 00:34:34 -04001658config X86_PMEM_LEGACY_DEVICE
1659 bool
1660
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001661config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001662 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001663 depends on PHYS_ADDR_T_64BIT
1664 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001665 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001666 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001667 help
1668 Treat memory marked using the non-standard e820 type of 12 as used
1669 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1670 The kernel will offer these regions to the 'pmem' driver so
1671 they can be used for persistent storage.
1672
1673 Say Y if unsure.
1674
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001675config HIGHPTE
1676 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001677 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001678 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001679 The VM uses one page table entry for each page of physical memory.
1680 For systems with a lot of RAM, this can be wasteful of precious
1681 low memory. Setting this option will put user-space page table
1682 entries in high memory.
1683
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001684config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001685 bool "Check for low memory corruption"
1686 ---help---
1687 Periodically check for memory corruption in low memory, which
1688 is suspected to be caused by BIOS. Even when enabled in the
1689 configuration, it is disabled at runtime. Enable it by
1690 setting "memory_corruption_check=1" on the kernel command
1691 line. By default it scans the low 64k of memory every 60
1692 seconds; see the memory_corruption_check_size and
1693 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001694 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001695
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001696 When enabled with the default parameters, this option has
1697 almost no overhead, as it reserves a relatively small amount
1698 of memory and scans it infrequently. It both detects corruption
1699 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001700
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001701 It is, however, intended as a diagnostic tool; if repeatable
1702 BIOS-originated corruption always affects the same memory,
1703 you can use memmap= to prevent the kernel from using that
1704 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001705
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001706config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001707 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001708 depends on X86_CHECK_BIOS_CORRUPTION
1709 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001710 ---help---
1711 Set whether the default state of memory_corruption_check is
1712 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001713
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001714config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001715 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1716 default 64
1717 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001718 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001719 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001720
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001721 The first page contains BIOS data structures that the kernel
1722 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001723
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001724 By default we reserve the first 64K of physical RAM, as a
1725 number of BIOSes are known to corrupt that memory range
1726 during events such as suspend/resume or monitor cable
1727 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001728
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001729 You can set this to 4 if you are absolutely sure that you
1730 trust the BIOS to get all its memory reservations and usages
1731 right. If you know your BIOS have problems beyond the
1732 default 64K area, you can set this to 640 to avoid using the
1733 entire low memory range.
1734
1735 If you have doubts about the BIOS (e.g. suspend/resume does
1736 not work or there's kernel crashes after certain hardware
1737 hotplug events) then you might want to enable
1738 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1739 typical corruption patterns.
1740
1741 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001742
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001743config MATH_EMULATION
1744 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001745 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001746 prompt "Math emulation" if X86_32
1747 ---help---
1748 Linux can emulate a math coprocessor (used for floating point
1749 operations) if you don't have one. 486DX and Pentium processors have
1750 a math coprocessor built in, 486SX and 386 do not, unless you added
1751 a 487DX or 387, respectively. (The messages during boot time can
1752 give you some hints here ["man dmesg"].) Everyone needs either a
1753 coprocessor or this emulation.
1754
1755 If you don't have a math coprocessor, you need to say Y here; if you
1756 say Y here even though you have a coprocessor, the coprocessor will
1757 be used nevertheless. (This behavior can be changed with the kernel
1758 command line option "no387", which comes handy if your coprocessor
1759 is broken. Try "man bootparam" or see the documentation of your boot
1760 loader (lilo or loadlin) about how to pass options to the kernel at
1761 boot time.) This means that it is a good idea to say Y here if you
1762 intend to use this kernel on different machines.
1763
1764 More information about the internals of the Linux math coprocessor
1765 emulation can be found in <file:arch/x86/math-emu/README>.
1766
1767 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1768 kernel, it won't hurt.
1769
1770config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001771 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001772 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001773 ---help---
1774 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1775 the Memory Type Range Registers (MTRRs) may be used to control
1776 processor access to memory ranges. This is most useful if you have
1777 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1778 allows bus write transfers to be combined into a larger transfer
1779 before bursting over the PCI/AGP bus. This can increase performance
1780 of image write operations 2.5 times or more. Saying Y here creates a
1781 /proc/mtrr file which may be used to manipulate your processor's
1782 MTRRs. Typically the X server should use this.
1783
1784 This code has a reasonably generic interface so that similar
1785 control registers on other processors can be easily supported
1786 as well:
1787
1788 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1789 Registers (ARRs) which provide a similar functionality to MTRRs. For
1790 these, the ARRs are used to emulate the MTRRs.
1791 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1792 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1793 write-combining. All of these processors are supported by this code
1794 and it makes sense to say Y here if you have one of them.
1795
1796 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1797 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1798 can lead to all sorts of problems, so it's good to say Y here.
1799
1800 You can safely say Y even if your machine doesn't have MTRRs, you'll
1801 just add about 9 KB to your kernel.
1802
Randy Dunlap7225e752008-07-26 17:54:22 -07001803 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001804
Yinghai Lu95ffa242008-04-29 03:52:33 -07001805config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001806 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001807 prompt "MTRR cleanup support"
1808 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001809 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001810 Convert MTRR layout from continuous to discrete, so X drivers can
1811 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001812
Thomas Gleixneraba37282008-07-15 14:48:48 +02001813 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001814 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001815 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001816
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001817 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001818
1819config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001820 int "MTRR cleanup enable value (0-1)"
1821 range 0 1
1822 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001823 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001824 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001825 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001826
Yinghai Lu12031a62008-05-02 02:40:22 -07001827config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1828 int "MTRR cleanup spare reg num (0-7)"
1829 range 0 7
1830 default "1"
1831 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001832 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001833 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001834 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001835
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001836config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001837 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001838 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001839 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001840 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001841 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001842
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001843 PATs are the modern equivalents of MTRRs and are much more
1844 flexible than MTRRs.
1845
1846 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001847 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001848
1849 If unsure, say Y.
1850
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001851config ARCH_USES_PG_UNCACHED
1852 def_bool y
1853 depends on X86_PAT
1854
H. Peter Anvin628c6242011-07-31 13:59:29 -07001855config ARCH_RANDOM
1856 def_bool y
1857 prompt "x86 architectural random number generator" if EXPERT
1858 ---help---
1859 Enable the x86 architectural RDRAND instruction
1860 (Intel Bull Mountain technology) to generate random numbers.
1861 If supported, this is a high bandwidth, cryptographically
1862 secure hardware random number generator.
1863
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001864config X86_SMAP
1865 def_bool y
1866 prompt "Supervisor Mode Access Prevention" if EXPERT
1867 ---help---
1868 Supervisor Mode Access Prevention (SMAP) is a security
1869 feature in newer Intel processors. There is a small
1870 performance cost if this enabled and turned on; there is
1871 also a small increase in the kernel size if this is enabled.
1872
1873 If unsure, say Y.
1874
Ricardo Neriaa35f892017-11-05 18:27:54 -08001875config X86_INTEL_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001876 def_bool y
Ricardo Neriaa35f892017-11-05 18:27:54 -08001877 depends on CPU_SUP_INTEL
1878 prompt "Intel User Mode Instruction Prevention" if EXPERT
1879 ---help---
1880 The User Mode Instruction Prevention (UMIP) is a security
1881 feature in newer Intel processors. If enabled, a general
Ricardo Neri796ebc82017-11-13 22:29:42 -08001882 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1883 or STR instructions are executed in user mode. These instructions
1884 unnecessarily expose information about the hardware state.
1885
1886 The vast majority of applications do not use these instructions.
1887 For the very few that do, software emulation is provided in
1888 specific cases in protected and virtual-8086 modes. Emulated
1889 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001890
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001891config X86_INTEL_MPX
1892 prompt "Intel MPX (Memory Protection Extensions)"
1893 def_bool n
Rik van Rieldf3735c2017-09-06 16:25:11 -07001894 # Note: only available in 64-bit mode due to VMA flags shortage
1895 depends on CPU_SUP_INTEL && X86_64
1896 select ARCH_USES_HIGH_VMA_FLAGS
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001897 ---help---
1898 MPX provides hardware features that can be used in
1899 conjunction with compiler-instrumented code to check
1900 memory references. It is designed to detect buffer
1901 overflow or underflow bugs.
1902
1903 This option enables running applications which are
1904 instrumented or otherwise use MPX. It does not use MPX
1905 itself inside the kernel or to protect the kernel
1906 against bad memory references.
1907
1908 Enabling this option will make the kernel larger:
1909 ~8k of kernel text and 36 bytes of data on a 64-bit
1910 defconfig. It adds a long to the 'mm_struct' which
1911 will increase the kernel memory overhead of each
1912 process and adds some branches to paths used during
1913 exec() and munmap().
1914
1915 For details, see Documentation/x86/intel_mpx.txt
1916
1917 If unsure, say N.
1918
Dave Hansen35e97792016-02-12 13:02:00 -08001919config X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001920 prompt "Intel Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001921 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001922 # Note: only available in 64-bit mode
Dave Hansen35e97792016-02-12 13:02:00 -08001923 depends on CPU_SUP_INTEL && X86_64
Ingo Molnar52c8e602016-11-15 10:15:03 +01001924 select ARCH_USES_HIGH_VMA_FLAGS
1925 select ARCH_HAS_PKEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001926 ---help---
1927 Memory Protection Keys provides a mechanism for enforcing
1928 page-based protections, but without requiring modification of the
1929 page tables when an application changes protection domains.
1930
1931 For details, see Documentation/x86/protection-keys.txt
1932
1933 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001934
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001935config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001936 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001937 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001938 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001939 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001940 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001941 This enables the kernel to use EFI runtime services that are
1942 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001943
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001944 This option is only useful on systems that have EFI firmware.
1945 In addition, you should use the latest ELILO loader available
1946 at <http://elilo.sourceforge.net> in order to take advantage
1947 of EFI runtime services. However, even with this option, the
1948 resultant kernel should continue to boot on existing non-EFI
1949 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001950
Matt Fleming291f3632011-12-12 21:27:52 +00001951config EFI_STUB
1952 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001953 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001954 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001955 ---help---
1956 This kernel feature allows a bzImage to be loaded directly
1957 by EFI firmware without the use of a bootloader.
1958
Roy Franz4172fe22013-09-22 15:45:25 -07001959 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001960
Matt Fleming7d453ee2014-01-10 18:52:06 +00001961config EFI_MIXED
1962 bool "EFI mixed-mode support"
1963 depends on EFI_STUB && X86_64
1964 ---help---
1965 Enabling this feature allows a 64-bit kernel to be booted
1966 on a 32-bit firmware, provided that your CPU supports 64-bit
1967 mode.
1968
1969 Note that it is not possible to boot a mixed-mode enabled
1970 kernel via the EFI boot stub - a bootloader that supports
1971 the EFI handover protocol must be used.
1972
1973 If unsure, say N.
1974
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001975config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001976 def_bool y
1977 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001978 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001979 This kernel feature is useful for number crunching applications
1980 that may need to compute untrusted bytecode during their
1981 execution. By using pipes or other transports made available to
1982 the process as file descriptors supporting the read/write
1983 syscalls, it's possible to isolate those applications in
1984 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001985 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001986 and the task is only allowed to execute a few safe syscalls
1987 defined by each seccomp mode.
1988
1989 If unsure, say Y. Only embedded should say N here.
1990
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001991source kernel/Kconfig.hz
1992
1993config KEXEC
1994 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001995 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001996 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001997 kexec is a system call that implements the ability to shutdown your
1998 current kernel, and to start another kernel. It is like a reboot
1999 but it is independent of the system firmware. And like a reboot
2000 you can start any kernel with it, not just Linux.
2001
2002 The name comes from the similarity to the exec system call.
2003
2004 It is an ongoing process to be certain the hardware in a machine
2005 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02002006 initially work for you. As of this writing the exact hardware
2007 interface is strongly in flux, so no good recommendation can be
2008 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002009
Vivek Goyal74ca3172014-08-29 15:18:46 -07002010config KEXEC_FILE
2011 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07002012 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07002013 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07002014 depends on X86_64
2015 depends on CRYPTO=y
2016 depends on CRYPTO_SHA256=y
2017 ---help---
2018 This is new version of kexec system call. This system call is
2019 file based and takes file descriptors as system call argument
2020 for kernel and initramfs as opposed to list of segments as
2021 accepted by previous system call.
2022
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002023config KEXEC_VERIFY_SIG
2024 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07002025 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002026 ---help---
2027 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002028 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002029
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002030 In addition to that option, you need to enable signature
2031 verification for the corresponding kernel image type being
2032 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002033
2034config KEXEC_BZIMAGE_VERIFY_SIG
2035 bool "Enable bzImage signature verification support"
2036 depends on KEXEC_VERIFY_SIG
2037 depends on SIGNED_PE_FILE_VERIFICATION
2038 select SYSTEM_TRUSTED_KEYRING
2039 ---help---
2040 Enable bzImage signature verification support.
2041
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002042config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002043 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002044 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002045 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002046 Generate crash dump after being started by kexec.
2047 This should be normally only set in special crash dump kernels
2048 which are loaded in the main kernel with kexec-tools into
2049 a specially reserved region and then later executed after
2050 a crash by kdump/kexec. The crash dump kernel must be compiled
2051 to a memory address not used by the main kernel or BIOS using
2052 PHYSICAL_START, or it must be built as a relocatable image
2053 (CONFIG_RELOCATABLE=y).
2054 For more details see Documentation/kdump/kdump.txt
2055
Huang Ying3ab83522008-07-25 19:45:07 -07002056config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002057 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002058 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002059 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07002060 Jump between original kernel and kexeced kernel and invoke
2061 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002062
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002063config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002064 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002065 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002066 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002067 This gives the physical address where the kernel is loaded.
2068
2069 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2070 bzImage will decompress itself to above physical address and
2071 run from there. Otherwise, bzImage will run from the address where
2072 it has been loaded by the boot loader and will ignore above physical
2073 address.
2074
2075 In normal kdump cases one does not have to set/change this option
2076 as now bzImage can be compiled as a completely relocatable image
2077 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2078 address. This option is mainly useful for the folks who don't want
2079 to use a bzImage for capturing the crash dump and want to use a
2080 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2081 to be specifically compiled to run from a specific memory area
2082 (normally a reserved region) and this option comes handy.
2083
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002084 So if you are using bzImage for capturing the crash dump,
2085 leave the value here unchanged to 0x1000000 and set
2086 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2087 for capturing the crash dump change this value to start of
2088 the reserved region. In other words, it can be set based on
2089 the "X" value as specified in the "crashkernel=YM@XM"
2090 command line boot parameter passed to the panic-ed
2091 kernel. Please take a look at Documentation/kdump/kdump.txt
2092 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002093
2094 Usage of bzImage for capturing the crash dump is recommended as
2095 one does not have to build two kernels. Same kernel can be used
2096 as production kernel and capture kernel. Above option should have
2097 gone away after relocatable bzImage support is introduced. But it
2098 is present because there are users out there who continue to use
2099 vmlinux for dump capture. This option should go away down the
2100 line.
2101
2102 Don't change this unless you know what you are doing.
2103
2104config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002105 bool "Build a relocatable kernel"
2106 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002107 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002108 This builds a kernel image that retains relocation information
2109 so it can be loaded someplace besides the default 1MB.
2110 The relocations tend to make the kernel binary about 10% larger,
2111 but are discarded at runtime.
2112
2113 One use is for the kexec on panic case where the recovery kernel
2114 must live at a different physical address than the primary
2115 kernel.
2116
2117 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2118 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002119 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002120
Kees Cook8ab38202013-10-10 17:18:14 -07002121config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002122 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002123 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002124 default y
Kees Cook8ab38202013-10-10 17:18:14 -07002125 ---help---
Baoquan Hee8581e32016-04-20 13:55:43 -07002126 In support of Kernel Address Space Layout Randomization (KASLR),
2127 this randomizes the physical address at which the kernel image
2128 is decompressed and the virtual address where the kernel
2129 image is mapped, as a security feature that deters exploit
2130 attempts relying on knowledge of the location of kernel
2131 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002132
Kees Cooked9f0072016-05-25 15:45:33 -07002133 On 64-bit, the kernel physical and virtual addresses are
2134 randomized separately. The physical address will be anywhere
2135 between 16MB and the top of physical memory (up to 64TB). The
2136 virtual address will be randomized from 16MB up to 1GB (9 bits
2137 of entropy). Note that this also reduces the memory space
2138 available to kernel modules from 1.5GB to 1GB.
2139
2140 On 32-bit, the kernel physical and virtual addresses are
2141 randomized together. They will be randomized from 16MB up to
2142 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002143
Baoquan Hee8581e32016-04-20 13:55:43 -07002144 Entropy is generated using the RDRAND instruction if it is
2145 supported. If RDTSC is supported, its value is mixed into
2146 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002147 supported, then entropy is read from the i8254 timer. The
2148 usable entropy is limited by the kernel being built using
2149 2GB addressing, and that PHYSICAL_ALIGN must be at a
2150 minimum of 2MB. As a result, only 10 bits of entropy are
2151 theoretically possible, but the implementations are further
2152 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002153
Ingo Molnar6807c842017-04-18 11:08:12 +02002154 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002155
2156# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002157config X86_NEED_RELOCS
2158 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002159 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002160
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002161config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002162 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002163 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002164 range 0x2000 0x1000000 if X86_32
2165 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002166 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002167 This value puts the alignment restrictions on physical address
2168 where kernel is loaded and run from. Kernel is compiled for an
2169 address which meets above alignment restriction.
2170
2171 If bootloader loads the kernel at a non-aligned address and
2172 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2173 address aligned to above value and run from there.
2174
2175 If bootloader loads the kernel at a non-aligned address and
2176 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2177 load address and decompress itself to the address it has been
2178 compiled for and run from there. The address for which kernel is
2179 compiled already meets above alignment restrictions. Hence the
2180 end result is that kernel runs from a physical address meeting
2181 above alignment restrictions.
2182
Kees Cooka0215062013-07-08 09:15:17 -07002183 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2184 this value must be a multiple of 0x200000.
2185
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002186 Don't change this unless you know what you are doing.
2187
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002188config RANDOMIZE_MEMORY
2189 bool "Randomize the kernel memory sections"
2190 depends on X86_64
2191 depends on RANDOMIZE_BASE
2192 default RANDOMIZE_BASE
2193 ---help---
2194 Randomizes the base virtual address of kernel memory sections
2195 (physical memory mapping, vmalloc & vmemmap). This security feature
2196 makes exploits relying on predictable memory locations less reliable.
2197
2198 The order of allocations remains unchanged. Entropy is generated in
2199 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2200 configuration have in average 30,000 different possible virtual
2201 addresses for each memory section.
2202
Ingo Molnar6807c842017-04-18 11:08:12 +02002203 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002204
Thomas Garnier90397a42016-06-21 17:47:06 -07002205config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2206 hex "Physical memory mapping padding" if EXPERT
2207 depends on RANDOMIZE_MEMORY
2208 default "0xa" if MEMORY_HOTPLUG
2209 default "0x0"
2210 range 0x1 0x40 if MEMORY_HOTPLUG
2211 range 0x0 0x40
2212 ---help---
2213 Define the padding in terabytes added to the existing physical
2214 memory size during kernel memory randomization. It is useful
2215 for memory hotplug support but reduces the entropy available for
2216 address randomization.
2217
2218 If unsure, leave at the default value.
2219
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002220config HOTPLUG_CPU
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002221 bool "Support for hot-pluggable CPUs"
Stephen Rothwell40b31362013-05-21 13:49:35 +10002222 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002223 ---help---
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002224 Say Y here to allow turning CPUs off and on. CPUs can be
2225 controlled through /sys/devices/system/cpu.
2226 ( Note: power management support will enable this option
2227 automatically on SMP systems. )
2228 Say N if you want to disable CPU hotplug.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002229
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002230config BOOTPARAM_HOTPLUG_CPU0
2231 bool "Set default setting of cpu0_hotpluggable"
2232 default n
Kees Cook2c922cd2013-01-22 13:01:19 -08002233 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002234 ---help---
2235 Set whether default state of cpu0_hotpluggable is on or off.
2236
2237 Say Y here to enable CPU0 hotplug by default. If this switch
2238 is turned on, there is no need to give cpu0_hotplug kernel
2239 parameter and the CPU0 hotplug feature is enabled by default.
2240
2241 Please note: there are two known CPU0 dependencies if you want
2242 to enable the CPU0 hotplug feature either by this switch or by
2243 cpu0_hotplug kernel parameter.
2244
2245 First, resume from hibernate or suspend always starts from CPU0.
2246 So hibernate and suspend are prevented if CPU0 is offline.
2247
2248 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2249 offline if any interrupt can not migrate out of CPU0. There may
2250 be other CPU0 dependencies.
2251
2252 Please make sure the dependencies are under your control before
2253 you enable this feature.
2254
2255 Say N if you don't want to enable CPU0 hotplug feature by default.
2256 You still can enable the CPU0 hotplug feature at boot by kernel
2257 parameter cpu0_hotplug.
2258
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002259config DEBUG_HOTPLUG_CPU0
2260 def_bool n
2261 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002262 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002263 ---help---
2264 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2265 soon as possible and boots up userspace with CPU0 offlined. User
2266 can online CPU0 back after boot time.
2267
2268 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2269 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2270 compilation or giving cpu0_hotplug kernel parameter at boot.
2271
2272 If unsure, say N.
2273
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002274config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002275 def_bool n
2276 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002277 depends on COMPAT_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002278 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002279 Certain buggy versions of glibc will crash if they are
2280 presented with a 32-bit vDSO that is not mapped at the address
2281 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002282
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002283 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2284 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2285 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2286 the only released version with the bug, but OpenSUSE 9
2287 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002288
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002289 The symptom of the bug is that everything crashes on startup, saying:
2290 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2291
2292 Saying Y here changes the default value of the vdso32 boot
2293 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2294 This works around the glibc bug but hurts performance.
2295
2296 If unsure, say N: if you are compiling your own kernel, you
2297 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002298
Kees Cook3dc33bd2015-08-12 17:55:19 -07002299choice
2300 prompt "vsyscall table for legacy applications"
2301 depends on X86_64
2302 default LEGACY_VSYSCALL_EMULATE
2303 help
2304 Legacy user code that does not know how to find the vDSO expects
2305 to be able to issue three syscalls by calling fixed addresses in
2306 kernel space. Since this location is not randomized with ASLR,
2307 it can be used to assist security vulnerability exploitation.
2308
2309 This setting can be changed at boot time via the kernel command
Andy Lutomirski076ca272018-03-07 11:12:27 -08002310 line parameter vsyscall=[emulate|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002311
2312 On a system with recent enough glibc (2.14 or newer) and no
2313 static binaries, you can say None without a performance penalty
2314 to improve security.
2315
2316 If unsure, select "Emulate".
2317
Kees Cook3dc33bd2015-08-12 17:55:19 -07002318 config LEGACY_VSYSCALL_EMULATE
2319 bool "Emulate"
2320 help
2321 The kernel traps and emulates calls into the fixed
2322 vsyscall address mapping. This makes the mapping
2323 non-executable, but it still contains known contents,
2324 which could be used in certain rare security vulnerability
2325 exploits. This configuration is recommended when userspace
2326 still uses the vsyscall area.
2327
2328 config LEGACY_VSYSCALL_NONE
2329 bool "None"
2330 help
2331 There will be no vsyscall mapping at all. This will
2332 eliminate any risk of ASLR bypass due to the vsyscall
2333 fixed address mapping. Attempts to use the vsyscalls
2334 will be reported to dmesg, so that either old or
2335 malicious userspace programs can be identified.
2336
2337endchoice
2338
Tim Bird516cbf32008-08-12 12:52:36 -07002339config CMDLINE_BOOL
2340 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002341 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002342 Allow for specifying boot arguments to the kernel at
2343 build time. On some systems (e.g. embedded ones), it is
2344 necessary or convenient to provide some or all of the
2345 kernel boot arguments with the kernel itself (that is,
2346 to not rely on the boot loader to provide them.)
2347
2348 To compile command line arguments into the kernel,
2349 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002350 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002351
2352 Systems with fully functional boot loaders (i.e. non-embedded)
2353 should leave this option set to 'N'.
2354
2355config CMDLINE
2356 string "Built-in kernel command string"
2357 depends on CMDLINE_BOOL
2358 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002359 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002360 Enter arguments here that should be compiled into the kernel
2361 image and used at boot time. If the boot loader provides a
2362 command line at boot time, it is appended to this string to
2363 form the full kernel command line, when the system boots.
2364
2365 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2366 change this behavior.
2367
2368 In most cases, the command line (whether built-in or provided
2369 by the boot loader) should specify the device for the root
2370 file system.
2371
2372config CMDLINE_OVERRIDE
2373 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002374 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002375 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002376 Set this option to 'Y' to have the kernel ignore the boot loader
2377 command line, and use ONLY the built-in command line.
2378
2379 This is used to work around broken boot loaders. This should
2380 be set to 'N' under normal conditions.
2381
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002382config MODIFY_LDT_SYSCALL
2383 bool "Enable the LDT (local descriptor table)" if EXPERT
2384 default y
2385 ---help---
2386 Linux can allow user programs to install a per-process x86
2387 Local Descriptor Table (LDT) using the modify_ldt(2) system
2388 call. This is required to run 16-bit or segmented code such as
2389 DOSEMU or some Wine programs. It is also used by some very old
2390 threading libraries.
2391
2392 Enabling this feature adds a small amount of overhead to
2393 context switches and increases the low-level kernel attack
2394 surface. Disabling it removes the modify_ldt(2) system call.
2395
2396 Saying 'N' here may make sense for embedded or server kernels.
2397
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002398source "kernel/livepatch/Kconfig"
2399
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002400endmenu
2401
Michal Hocko3072e412017-09-08 16:11:39 -07002402config ARCH_HAS_ADD_PAGES
2403 def_bool y
2404 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2405
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002406config ARCH_ENABLE_MEMORY_HOTPLUG
2407 def_bool y
2408 depends on X86_64 || (X86_32 && HIGHMEM)
2409
Gary Hade35551052008-10-31 10:52:03 -07002410config ARCH_ENABLE_MEMORY_HOTREMOVE
2411 def_bool y
2412 depends on MEMORY_HOTPLUG
2413
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002414config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002415 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002416 depends on NUMA
2417
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002418config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2419 def_bool y
2420 depends on X86_64 || X86_PAE
2421
Naoya Horiguchic177c812014-06-04 16:05:35 -07002422config ARCH_ENABLE_HUGEPAGE_MIGRATION
2423 def_bool y
2424 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2425
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002426config ARCH_ENABLE_THP_MIGRATION
2427 def_bool y
2428 depends on X86_64 && TRANSPARENT_HUGEPAGE
2429
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002430menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002431
2432config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002433 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002434 depends on X86_64 && HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002435
2436source "kernel/power/Kconfig"
2437
2438source "drivers/acpi/Kconfig"
2439
Feng Tangefafc8b2009-08-14 15:23:29 -04002440source "drivers/sfi/Kconfig"
2441
Andi Kleena6b68072008-01-30 13:32:49 +01002442config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002443 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002444 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002445
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002446menuconfig APM
2447 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002448 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002449 ---help---
2450 APM is a BIOS specification for saving power using several different
2451 techniques. This is mostly useful for battery powered laptops with
2452 APM compliant BIOSes. If you say Y here, the system time will be
2453 reset after a RESUME operation, the /proc/apm device will provide
2454 battery status information, and user-space programs will receive
2455 notification of APM "events" (e.g. battery status change).
2456
2457 If you select "Y" here, you can disable actual use of the APM
2458 BIOS by passing the "apm=off" option to the kernel at boot time.
2459
2460 Note that the APM support is almost completely disabled for
2461 machines with more than one CPU.
2462
2463 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002464 and more information, read <file:Documentation/power/apm-acpi.txt>
2465 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002466 <http://www.tldp.org/docs.html#howto>.
2467
2468 This driver does not spin down disk drives (see the hdparm(8)
2469 manpage ("man 8 hdparm") for that), and it doesn't turn off
2470 VESA-compliant "green" monitors.
2471
2472 This driver does not support the TI 4000M TravelMate and the ACER
2473 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2474 desktop machines also don't have compliant BIOSes, and this driver
2475 may cause those machines to panic during the boot phase.
2476
2477 Generally, if you don't have a battery in your machine, there isn't
2478 much point in using this driver and you should say N. If you get
2479 random kernel OOPSes or reboots that don't seem to be related to
2480 anything, try disabling/enabling this option (or disabling/enabling
2481 APM in your BIOS).
2482
2483 Some other things you should try when experiencing seemingly random,
2484 "weird" problems:
2485
2486 1) make sure that you have enough swap space and that it is
2487 enabled.
2488 2) pass the "no-hlt" option to the kernel
2489 3) switch on floating point emulation in the kernel and pass
2490 the "no387" option to the kernel
2491 4) pass the "floppy=nodma" option to the kernel
2492 5) pass the "mem=4M" option to the kernel (thereby disabling
2493 all but the first 4 MB of RAM)
2494 6) make sure that the CPU is not over clocked.
2495 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2496 8) disable the cache from your BIOS settings
2497 9) install a fan for the video card or exchange video RAM
2498 10) install a better fan for the CPU
2499 11) exchange RAM chips
2500 12) exchange the motherboard.
2501
2502 To compile this driver as a module, choose M here: the
2503 module will be called apm.
2504
2505if APM
2506
2507config APM_IGNORE_USER_SUSPEND
2508 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002509 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002510 This option will ignore USER SUSPEND requests. On machines with a
2511 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2512 series notebooks, it is necessary to say Y because of a BIOS bug.
2513
2514config APM_DO_ENABLE
2515 bool "Enable PM at boot time"
2516 ---help---
2517 Enable APM features at boot time. From page 36 of the APM BIOS
2518 specification: "When disabled, the APM BIOS does not automatically
2519 power manage devices, enter the Standby State, enter the Suspend
2520 State, or take power saving steps in response to CPU Idle calls."
2521 This driver will make CPU Idle calls when Linux is idle (unless this
2522 feature is turned off -- see "Do CPU IDLE calls", below). This
2523 should always save battery power, but more complicated APM features
2524 will be dependent on your BIOS implementation. You may need to turn
2525 this option off if your computer hangs at boot time when using APM
2526 support, or if it beeps continuously instead of suspending. Turn
2527 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2528 T400CDT. This is off by default since most machines do fine without
2529 this feature.
2530
2531config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002532 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002533 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002534 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002535 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2536 On some machines, this can activate improved power savings, such as
2537 a slowed CPU clock rate, when the machine is idle. These idle calls
2538 are made after the idle loop has run for some length of time (e.g.,
2539 333 mS). On some machines, this will cause a hang at boot time or
2540 whenever the CPU becomes idle. (On machines with more than one CPU,
2541 this option does nothing.)
2542
2543config APM_DISPLAY_BLANK
2544 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002545 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002546 Enable console blanking using the APM. Some laptops can use this to
2547 turn off the LCD backlight when the screen blanker of the Linux
2548 virtual console blanks the screen. Note that this is only used by
2549 the virtual console screen blanker, and won't turn off the backlight
2550 when using the X Window system. This also doesn't have anything to
2551 do with your VESA-compliant power-saving monitor. Further, this
2552 option doesn't work for all laptops -- it might not turn off your
2553 backlight at all, or it might print a lot of errors to the console,
2554 especially if you are using gpm.
2555
2556config APM_ALLOW_INTS
2557 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002558 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002559 Normally we disable external interrupts while we are making calls to
2560 the APM BIOS as a measure to lessen the effects of a badly behaving
2561 BIOS implementation. The BIOS should reenable interrupts if it
2562 needs to. Unfortunately, some BIOSes do not -- especially those in
2563 many of the newer IBM Thinkpads. If you experience hangs when you
2564 suspend, try setting this to Y. Otherwise, say N.
2565
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002566endif # APM
2567
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002568source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002569
2570source "drivers/cpuidle/Kconfig"
2571
Andy Henroid27471fd2008-10-09 11:45:22 -07002572source "drivers/idle/Kconfig"
2573
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002574endmenu
2575
2576
2577menu "Bus options (PCI etc.)"
2578
2579config PCI
Ingo Molnar1ac97012008-05-19 14:10:14 +02002580 bool "PCI support"
Adrian Bunk1c858082008-01-30 13:32:32 +01002581 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002582 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002583 Find out whether you have a PCI motherboard. PCI is the name of a
2584 bus system, i.e. the way the CPU talks to the other stuff inside
2585 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2586 VESA. If you have PCI, say Y, otherwise N.
2587
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002588choice
2589 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002590 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002591 default PCI_GOANY
2592 ---help---
2593 On PCI systems, the BIOS can be used to detect the PCI devices and
2594 determine their configuration. However, some old PCI motherboards
2595 have BIOS bugs and may crash if this is done. Also, some embedded
2596 PCI-based systems don't have any BIOS at all. Linux can also try to
2597 detect the PCI hardware directly without using the BIOS.
2598
2599 With this option, you can specify how Linux should detect the
2600 PCI devices. If you choose "BIOS", the BIOS will be used,
2601 if you choose "Direct", the BIOS won't be used, and if you
2602 choose "MMConfig", then PCI Express MMCONFIG will be used.
2603 If you choose "Any", the kernel will try MMCONFIG, then the
2604 direct access method and falls back to the BIOS if that doesn't
2605 work. If unsure, go with the default, which is "Any".
2606
2607config PCI_GOBIOS
2608 bool "BIOS"
2609
2610config PCI_GOMMCONFIG
2611 bool "MMConfig"
2612
2613config PCI_GODIRECT
2614 bool "Direct"
2615
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002616config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002617 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002618 depends on OLPC
2619
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002620config PCI_GOANY
2621 bool "Any"
2622
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002623endchoice
2624
2625config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002626 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002627 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002628
2629# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2630config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002631 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002632 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002633
2634config PCI_MMCONFIG
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002635 def_bool y
Feng Tang5f0db7a2009-08-14 15:37:50 -04002636 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002637
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002638config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002639 def_bool y
2640 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002641
Alex Nixonb5401a92010-03-18 16:31:34 -04002642config PCI_XEN
2643 def_bool y
2644 depends on PCI && XEN
2645 select SWIOTLB_XEN
2646
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002647config PCI_DOMAINS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002648 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002649 depends on PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002650
2651config PCI_MMCONFIG
2652 bool "Support mmconfig PCI config space access"
2653 depends on X86_64 && PCI && ACPI
2654
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002655config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002656 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002657 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002658 help
2659 Read the PCI windows out of the CNB20LE host bridge. This allows
2660 PCI hotplug to work on systems with the CNB20LE chipset which do
2661 not have ACPI.
2662
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002663 There's no public spec for this chipset, and this functionality
2664 is known to be incomplete.
2665
2666 You should say N unless you know you need this.
2667
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002668source "drivers/pci/Kconfig"
2669
William Breathitt Gray3a495512016-05-27 18:08:27 -04002670config ISA_BUS
2671 bool "ISA-style bus support on modern systems" if EXPERT
2672 select ISA_BUS_API
2673 help
2674 Enables ISA-style drivers on modern systems. This is necessary to
2675 support PC/104 devices on X86_64 platforms.
2676
2677 If unsure, say N.
2678
David Rientjes1c00f012011-03-22 16:34:59 -07002679# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002680config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002681 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2682 default y
2683 help
2684 Enables ISA-style DMA support for devices requiring such controllers.
2685 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002686
Linus Torvalds51e68d02016-05-21 10:25:19 -07002687if X86_32
2688
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002689config ISA
2690 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002691 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002692 Find out whether you have ISA slots on your motherboard. ISA is the
2693 name of a bus system, i.e. the way the CPU talks to the other stuff
2694 inside your box. Other bus systems are PCI, EISA, MicroChannel
2695 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2696 newer boards don't support it. If you have ISA, say Y, otherwise N.
2697
2698config EISA
2699 bool "EISA support"
2700 depends on ISA
2701 ---help---
2702 The Extended Industry Standard Architecture (EISA) bus was
2703 developed as an open alternative to the IBM MicroChannel bus.
2704
2705 The EISA bus provided some of the features of the IBM MicroChannel
2706 bus while maintaining backward compatibility with cards made for
2707 the older ISA bus. The EISA bus saw limited use between 1988 and
2708 1995 when it was made obsolete by the PCI bus.
2709
2710 Say Y here if you are building a kernel for an EISA-based machine.
2711
2712 Otherwise, say N.
2713
2714source "drivers/eisa/Kconfig"
2715
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002716config SCx200
2717 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002718 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002719 This provides basic support for National Semiconductor's
2720 (now AMD's) Geode processors. The driver probes for the
2721 PCI-IDs of several on-chip devices, so its a good dependency
2722 for other scx200_* drivers.
2723
2724 If compiled as a module, the driver is named scx200.
2725
2726config SCx200HR_TIMER
2727 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002728 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002729 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002730 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002731 This driver provides a clocksource built upon the on-chip
2732 27MHz high-resolution timer. Its also a workaround for
2733 NSC Geode SC-1100's buggy TSC, which loses time when the
2734 processor goes idle (as is done by the scheduler). The
2735 other workaround is idle=poll boot option.
2736
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002737config OLPC
2738 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002739 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002740 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002741 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002742 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002743 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002744 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002745 Add support for detecting the unique features of the OLPC
2746 XO hardware.
2747
Daniel Drakea3128582011-06-25 17:34:10 +01002748config OLPC_XO1_PM
2749 bool "OLPC XO-1 Power Management"
Daniel Drake97c4cb72011-06-25 17:34:11 +01002750 depends on OLPC && MFD_CS5535 && PM_SLEEP
Daniel Drakea3128582011-06-25 17:34:10 +01002751 select MFD_CORE
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002752 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002753 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002754
Daniel Drakecfee9592011-06-25 17:34:17 +01002755config OLPC_XO1_RTC
2756 bool "OLPC XO-1 Real Time Clock"
2757 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2758 ---help---
2759 Add support for the XO-1 real time clock, which can be used as a
2760 programmable wakeup source.
2761
Daniel Drake7feda8e2011-06-25 17:34:12 +01002762config OLPC_XO1_SCI
2763 bool "OLPC XO-1 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002764 depends on OLPC && OLPC_XO1_PM
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002765 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002766 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002767 select GPIO_CS5535
2768 select MFD_CORE
2769 ---help---
2770 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002771 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002772 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002773 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002774 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002775 - AC adapter status updates
2776 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002777
Daniel Drakea0f30f52011-06-25 17:34:18 +01002778config OLPC_XO15_SCI
2779 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002780 depends on OLPC && ACPI
2781 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002782 ---help---
2783 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2784 - EC-driven system wakeups
2785 - AC adapter status updates
2786 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002787
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002788config ALIX
2789 bool "PCEngines ALIX System Support (LED setup)"
2790 select GPIOLIB
2791 ---help---
2792 This option enables system support for the PCEngines ALIX.
2793 At present this just sets up LEDs for GPIO control on
2794 ALIX2/3/6 boards. However, other system specific setup should
2795 get added here.
2796
2797 Note: You must still enable the drivers for GPIO and LED support
2798 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2799
2800 Note: You have to set alix.force=1 for boards with Award BIOS.
2801
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002802config NET5501
2803 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2804 select GPIOLIB
2805 ---help---
2806 This option enables system support for the Soekris Engineering net5501.
2807
Philip A. Prindeville31970592012-01-14 01:45:39 -07002808config GEOS
2809 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2810 select GPIOLIB
2811 depends on DMI
2812 ---help---
2813 This option enables system support for the Traverse Technologies GEOS.
2814
Vivien Didelot7d029122013-01-04 16:18:14 -05002815config TS5500
2816 bool "Technologic Systems TS-5500 platform support"
2817 depends on MELAN
2818 select CHECK_SIGNATURE
2819 select NEW_LEDS
2820 select LEDS_CLASS
2821 ---help---
2822 This option enables system support for the Technologic Systems TS-5500.
2823
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002824endif # X86_32
2825
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002826config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002827 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002828 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002829
2830source "drivers/pcmcia/Kconfig"
2831
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002832config RAPIDIO
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002833 tristate "RapidIO support"
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002834 depends on PCI
2835 default n
2836 help
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002837 If enabled this option will include drivers and the core
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002838 infrastructure code to support RapidIO interconnect devices.
2839
2840source "drivers/rapidio/Kconfig"
2841
David Herrmanne3263ab2013-08-02 14:05:22 +02002842config X86_SYSFB
2843 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2844 help
2845 Firmwares often provide initial graphics framebuffers so the BIOS,
2846 bootloader or kernel can show basic video-output during boot for
2847 user-guidance and debugging. Historically, x86 used the VESA BIOS
2848 Extensions and EFI-framebuffers for this, which are mostly limited
2849 to x86.
2850 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2851 framebuffers so the new generic system-framebuffer drivers can be
2852 used on x86. If the framebuffer is not compatible with the generic
2853 modes, it is adverticed as fallback platform framebuffer so legacy
2854 drivers like efifb, vesafb and uvesafb can pick it up.
2855 If this option is not selected, all system framebuffers are always
2856 marked as fallback platform framebuffers as usual.
2857
2858 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2859 not be able to pick up generic system framebuffers if this option
2860 is selected. You are highly encouraged to enable simplefb as
2861 replacement if you select this option. simplefb can correctly deal
2862 with generic system framebuffers. But you should still keep vesafb
2863 and others enabled as fallback if a system framebuffer is
2864 incompatible with simplefb.
2865
2866 If unsure, say Y.
2867
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002868endmenu
2869
2870
2871menu "Executable file formats / Emulations"
2872
2873source "fs/Kconfig.binfmt"
2874
2875config IA32_EMULATION
2876 bool "IA32 Emulation"
2877 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002878 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002879 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002880 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002881 select COMPAT_OLD_SIGACTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002882 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002883 Include code to run legacy 32-bit programs under a
2884 64-bit kernel. You should likely turn this on, unless you're
2885 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002886
2887config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002888 tristate "IA32 a.out support"
2889 depends on IA32_EMULATION
2890 ---help---
2891 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002892
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002893config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002894 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002895 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002896 ---help---
2897 Include code to run binaries for the x32 native 32-bit ABI
2898 for 64-bit processors. An x32 process gets access to the
2899 full 64-bit register file and wide data path while leaving
2900 pointers at 32 bits for smaller memory footprint.
2901
2902 You will need a recent binutils (2.22 or later) with
2903 elf32_x86_64 support enabled to compile a kernel with this
2904 option set.
2905
Ingo Molnar953fee12016-11-15 10:22:52 +01002906config COMPAT_32
2907 def_bool y
2908 depends on IA32_EMULATION || X86_32
2909 select HAVE_UID16
2910 select OLD_SIGSUSPEND3
2911
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002912config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002913 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002914 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002915
Jan Beulich3120e252012-09-10 12:41:45 +01002916if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002917config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002918 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002919
2920config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002921 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002922 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002923endif
David Howellsee009e4a02011-03-07 15:06:20 +00002924
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002925endmenu
2926
2927
Keith Packarde5beae12008-11-03 18:21:45 +01002928config HAVE_ATOMIC_IOMAP
2929 def_bool y
2930 depends on X86_32
2931
Alessandro Rubini4692d772012-04-04 19:39:58 +02002932config X86_DEV_DMA_OPS
2933 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002934 depends on X86_64 || STA2X11
Alessandro Rubini4692d772012-04-04 19:39:58 +02002935
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002936config X86_DMA_REMAP
2937 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002938 depends on STA2X11
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002939
Kirill A. Shutemove5855132017-06-06 14:31:20 +03002940config HAVE_GENERIC_GUP
2941 def_bool y
2942
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002943source "net/Kconfig"
2944
2945source "drivers/Kconfig"
2946
2947source "drivers/firmware/Kconfig"
2948
2949source "fs/Kconfig"
2950
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002951source "arch/x86/Kconfig.debug"
2952
2953source "security/Kconfig"
2954
2955source "crypto/Kconfig"
2956
Avi Kivityedf88412007-12-16 11:02:48 +02002957source "arch/x86/kvm/Kconfig"
2958
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002959source "lib/Kconfig"