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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
Yinghai Lu26f7ef12009-01-29 14:19:22 -0800426config X86_BIGSMP
427 bool "Support for big SMP systems with more than 8 CPUs"
428 depends on X86_32 && SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100429 ---help---
Yinghai Lu26f7ef12009-01-29 14:19:22 -0800430 This option is needed for the systems that have more than 8 CPUs
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100431
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000432config GOLDFISH
433 def_bool y
434 depends on X86_GOLDFISH
435
David Woodhouse76b04382018-01-11 21:46:25 +0000436config RETPOLINE
437 bool "Avoid speculative indirect branches in kernel"
438 default y
439 help
440 Compile kernel with the retpoline compiler options to guard against
441 kernel-to-user data leaks by avoiding speculative indirect
442 branches. Requires a compiler with -mindirect-branch=thunk-extern
443 support for full protection. The kernel may run slower.
444
445 Without compiler support, at least indirect branches in assembler
446 code are eliminated. Since this includes the syscall entry path,
447 it is not entirely pointless.
448
Vikas Shivappaf01d7d512017-07-25 14:14:22 -0700449config INTEL_RDT
450 bool "Intel Resource Director Technology support"
Fenghua Yu78e99b42016-10-22 06:19:53 -0700451 default n
452 depends on X86 && CPU_SUP_INTEL
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100453 select KERNFS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700454 help
Vikas Shivappaf01d7d512017-07-25 14:14:22 -0700455 Select to enable resource allocation and monitoring which are
456 sub-features of Intel Resource Director Technology(RDT). More
457 information about RDT can be found in the Intel x86
458 Architecture Software Developer Manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700459
460 Say N if unsure.
461
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800462if X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800463config X86_EXTENDED_PLATFORM
464 bool "Support for extended (non-PC) x86 platforms"
465 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100466 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100467 If you disable this option then the kernel will only support
468 standard PC platforms. (which covers the vast majority of
469 systems out there.)
470
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800471 If you enable this option then you'll be able to select support
472 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100473 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800474 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800475 RDC R-321x SoC
476 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200477 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200478 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100479
480 If you have one of these systems, or if you want to build a
481 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800482endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100483
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800484if X86_64
485config X86_EXTENDED_PLATFORM
486 bool "Support for extended (non-PC) x86 platforms"
487 default y
488 ---help---
489 If you disable this option then the kernel will only support
490 standard PC platforms. (which covers the vast majority of
491 systems out there.)
492
493 If you enable this option then you'll be able to select support
494 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800495 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800496 ScaleMP vSMP
497 SGI Ultraviolet
498
499 If you have one of these systems, or if you want to build a
500 generic distribution kernel, say Y here - otherwise say N.
501endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800502# This is an alphabetically sorted list of 64 bit extended platforms
503# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800504config X86_NUMACHIP
505 bool "Numascale NumaChip"
506 depends on X86_64
507 depends on X86_EXTENDED_PLATFORM
508 depends on NUMA
509 depends on SMP
510 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700511 depends on PCI_MMCONFIG
Steffen Persvold44b111b52011-12-06 00:07:26 +0800512 ---help---
513 Adds support for Numascale NumaChip large-SMP systems. Needed to
514 enable more than ~168 cores.
515 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100516
Ingo Molnar6a485652009-01-27 18:29:13 +0100517config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800518 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100519 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100520 select PARAVIRT
521 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800522 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300523 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100524 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100525 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
526 supposed to run on these EM64T-based machines. Only choose this option
527 if you have one of these machines.
528
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800529config X86_UV
530 bool "SGI Ultraviolet"
531 depends on X86_64
532 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500533 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800534 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700535 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200536 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800537 ---help---
538 This option is needed in order to support SGI Ultraviolet systems.
539 If you don't have one of these, you should say N here.
540
541# Following is an alphabetically sorted list of 32 bit extended platforms
542# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100543
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000544config X86_GOLDFISH
545 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100546 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000547 ---help---
548 Enable support for the Goldfish virtual platform used primarily
549 for Android development. Unless you are building for the Android
550 Goldfish emulator say N here.
551
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800552config X86_INTEL_CE
553 bool "CE4100 TV platform"
554 depends on PCI
555 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800556 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800557 depends on X86_32
558 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800559 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100560 select OF
561 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800562 ---help---
563 Select for the Intel CE media processor (CE4100) SOC.
564 This option compiles in support for the CE4100 SOC for settop
565 boxes and media devices.
566
David Cohen4cb9b002013-12-16 17:37:26 -0800567config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100568 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100569 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800570 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000571 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200572 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000573 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000574 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800575 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000576 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000577 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000578 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000579 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000580 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800581 Select to build a kernel capable of supporting Intel MID (Mobile
582 Internet Device) platform systems which do not have the PCI legacy
583 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000584
David Cohen4cb9b002013-12-16 17:37:26 -0800585 Intel MID platforms are based on an Intel processor and chipset which
586 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100587
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000588config X86_INTEL_QUARK
589 bool "Intel Quark platform support"
590 depends on X86_32
591 depends on X86_EXTENDED_PLATFORM
592 depends on X86_PLATFORM_DEVICES
593 depends on X86_TSC
594 depends on PCI
595 depends on PCI_GOANY
596 depends on X86_IO_APIC
597 select IOSF_MBI
598 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200599 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000600 ---help---
601 Select to include support for Quark X1000 SoC.
602 Say Y here if you have a Quark based system such as the Arduino
603 compatible Intel Galileo.
604
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000605config X86_INTEL_LPSS
606 bool "Intel Low Power Subsystem Support"
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100607 depends on X86 && ACPI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000608 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300609 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100610 select IOSF_MBI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000611 ---help---
612 Select to build support for Intel Low Power Subsystem such as
613 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300614 things like clock tree (common clock framework) and pincontrol
615 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000616
Ken Xue92082a82015-02-06 08:27:51 +0800617config X86_AMD_PLATFORM_DEVICE
618 bool "AMD ACPI2Platform devices support"
619 depends on ACPI
620 select COMMON_CLK
621 select PINCTRL
622 ---help---
623 Select to interpret AMD specific ACPI device to platform device
624 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
625 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
626 implemented under PINCTRL subsystem.
627
David E. Boxced3ce72014-09-17 22:13:50 -0700628config IOSF_MBI
629 tristate "Intel SoC IOSF Sideband support for SoC platforms"
630 depends on PCI
631 ---help---
632 This option enables sideband register access support for Intel SoC
633 platforms. On these platforms the IOSF sideband is used in lieu of
634 MSR's for some register accesses, mostly but not limited to thermal
635 and power. Drivers may query the availability of this device to
636 determine if they need the sideband in order to work on these
637 platforms. The sideband is available on the following SoC products.
638 This list is not meant to be exclusive.
639 - BayTrail
640 - Braswell
641 - Quark
642
643 You should say Y if you are running a kernel on one of these SoC's.
644
David E. Boxed2226b2014-09-17 22:13:51 -0700645config IOSF_MBI_DEBUG
646 bool "Enable IOSF sideband access through debugfs"
647 depends on IOSF_MBI && DEBUG_FS
648 ---help---
649 Select this option to expose the IOSF sideband access registers (MCR,
650 MDR, MCRX) through debugfs to write and read register information from
651 different units on the SoC. This is most useful for obtaining device
652 state information for debug and analysis. As this is a general access
653 mechanism, users of this option would have specific knowledge of the
654 device they want to access.
655
656 If you don't require the option or are in doubt, say N.
657
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800658config X86_RDC321X
659 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100660 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800661 depends on X86_EXTENDED_PLATFORM
662 select M486
663 select X86_REBOOTFIXUPS
664 ---help---
665 This option is needed for RDC R-321x system-on-chip, also known
666 as R-8610-(G).
667 If you don't have one of these chips, you should say N here.
668
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100669config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100670 bool "Support non-standard 32-bit SMP architectures"
671 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800672 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100673 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800674 This option compiles in the bigsmp and STA2X11 default
675 subarchitectures. It is intended for a generic binary
676 kernel. If you select them all, kernel will probe it one by
677 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700678
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800679# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700680
Linus Torvaldsd949f362009-09-26 09:35:07 -0700681config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100682 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700683 # MCE code calls memory_failure():
684 depends on X86_MCE
685 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700686 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
687 depends on X86_64 || !SPARSEMEM
688 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700689
Alessandro Rubini83125a32012-04-04 19:40:21 +0200690config STA2X11
691 bool "STA2X11 Companion Chip Support"
692 depends on X86_32_NON_STANDARD && PCI
693 select X86_DEV_DMA_OPS
694 select X86_DMA_REMAP
695 select SWIOTLB
696 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200697 select GPIOLIB
Alessandro Rubini83125a32012-04-04 19:40:21 +0200698 default n
699 ---help---
700 This adds support for boards based on the STA2X11 IO-Hub,
701 a.k.a. "ConneXt". The chip is used in place of the standard
702 PC chipset, so all "standard" peripherals are missing. If this
703 option is selected the kernel will still be able to boot on
704 standard PC machines.
705
Shérab82148d12010-09-25 06:06:57 +0200706config X86_32_IRIS
707 tristate "Eurobraille/Iris poweroff module"
708 depends on X86_32
709 ---help---
710 The Iris machines from EuroBraille do not have APM or ACPI support
711 to shut themselves down properly. A special I/O sequence is
712 needed to do so, which is what this module does at
713 kernel shutdown.
714
715 This is only for Iris machines from EuroBraille.
716
717 If unused, say N.
718
Ingo Molnarae1e9132008-11-11 09:05:16 +0100719config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100720 def_bool y
721 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800722 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100723 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100724 Calculate simpler /proc/<PID>/wchan values. If this option
725 is disabled then wchan values will recurse back to the
726 caller function. This provides more accurate wchan values,
727 at the expense of slightly more scheduling overhead.
728
729 If in doubt, say "Y".
730
Borislav Petkov6276a072013-03-04 21:20:21 +0100731menuconfig HYPERVISOR_GUEST
732 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100733 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100734 Say Y here to enable options for running Linux under various hyper-
735 visors. This option enables basic hypervisor detection and platform
736 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100737
Borislav Petkov6276a072013-03-04 21:20:21 +0100738 If you say N, all options in this submenu will be skipped and
739 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100740
Borislav Petkov6276a072013-03-04 21:20:21 +0100741if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100742
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100743config PARAVIRT
744 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100745 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100746 This changes the kernel so it can modify itself when it is run
747 under a hypervisor, potentially improving performance significantly
748 over full virtualization. However, when run without a hypervisor
749 the kernel is theoretically slower and slightly larger.
750
Borislav Petkov6276a072013-03-04 21:20:21 +0100751config PARAVIRT_DEBUG
752 bool "paravirt-ops debugging"
753 depends on PARAVIRT && DEBUG_KERNEL
754 ---help---
755 Enable to debug paravirt_ops internals. Specifically, BUG if
756 a paravirt_op is missing when it is called.
757
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700758config PARAVIRT_SPINLOCKS
759 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700760 depends on PARAVIRT && SMP
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700761 ---help---
762 Paravirtualized spinlocks allow a pvops backend to replace the
763 spinlock implementation with something virtualization-friendly
764 (for example, block the virtual CPU rather than spinning).
765
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530766 It has a minimal impact on native kernels and gives a nice performance
767 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700768
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530769 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700770
Waiman Long45e898b2015-11-09 19:09:25 -0500771config QUEUED_LOCK_STAT
772 bool "Paravirt queued spinlock statistics"
Peter Zijlstracfd89832016-05-18 20:43:02 +0200773 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
Waiman Long45e898b2015-11-09 19:09:25 -0500774 ---help---
775 Enable the collection of statistical data on the slowpath
776 behavior of paravirtualized queued spinlocks and report
777 them on debugfs.
778
Borislav Petkov6276a072013-03-04 21:20:21 +0100779source "arch/x86/xen/Kconfig"
780
781config KVM_GUEST
782 bool "KVM Guest support (including kvmclock)"
783 depends on PARAVIRT
784 select PARAVIRT_CLOCK
785 default y
786 ---help---
787 This option enables various optimizations for running under the KVM
788 hypervisor. It includes a paravirtualized clock, so that instead
789 of relying on a PIT (or probably other) emulation by the
790 underlying device model, the host provides the guest with
791 timing infrastructure such as time of day, and system time
792
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530793config KVM_DEBUG_FS
794 bool "Enable debug information for KVM Guests in debugfs"
795 depends on KVM_GUEST && DEBUG_FS
796 default n
797 ---help---
798 This option enables collection of various statistics for KVM guest.
799 Statistics are displayed in debugfs filesystem. Enabling this option
800 may incur significant overhead.
801
Borislav Petkov6276a072013-03-04 21:20:21 +0100802config PARAVIRT_TIME_ACCOUNTING
803 bool "Paravirtual steal time accounting"
804 depends on PARAVIRT
805 default n
806 ---help---
807 Select this option to enable fine granularity task steal time
808 accounting. Time spent executing other tasks in parallel with
809 the current vCPU is discounted from the vCPU power. To account for
810 that, there can be a small performance impact.
811
812 If in doubt, say N here.
813
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200814config PARAVIRT_CLOCK
815 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200816
Jan Kiszka4a362602017-11-27 09:11:46 +0100817config JAILHOUSE_GUEST
818 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100819 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100820 select X86_PM_TIMER
Jan Kiszka4a362602017-11-27 09:11:46 +0100821 ---help---
822 This option allows to run Linux as guest in a Jailhouse non-root
823 cell. You can leave this option disabled if you only want to start
824 Jailhouse and run Linux afterwards in the root cell.
825
Borislav Petkov6276a072013-03-04 21:20:21 +0100826endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400827
Yinghai Lu08677212010-02-10 01:20:20 -0800828config NO_BOOTMEM
Yinghai Lu774ea0b2010-08-25 13:39:18 -0700829 def_bool y
Yinghai Lu08677212010-02-10 01:20:20 -0800830
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100831source "arch/x86/Kconfig.cpu"
832
833config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100834 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100835 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100836 ---help---
837 Use the IA-PC HPET (High Precision Event Timer) to manage
838 time in preference to the PIT and RTC, if a HPET is
839 present.
840 HPET is the next generation timer replacing legacy 8254s.
841 The HPET provides a stable time base on SMP
842 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200843 as it is off-chip. The interface used is documented
844 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100845
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100846 You can safely choose Y here. However, HPET will only be
847 activated if the platform and the BIOS support this feature.
848 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100849
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100850 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100851
852config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100853 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800854 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100855
Jacob Panbb24c472009-09-02 07:37:17 -0700856config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000857 def_bool y if X86_INTEL_MID
858 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100859 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000860 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700861 help
862 APB timer is the replacement for 8254, HPET on X86 MID platforms.
863 The APBT provides a stable time base on SMP
864 systems, unlike the TSC, but it is more expensive to access,
865 as it is off-chip. APB timers are always running regardless of CPU
866 C states, they are used as per CPU clockevent device when possible.
867
David Rientjes6a108a12011-01-20 14:44:16 -0800868# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100869# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700870config DMI
871 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800872 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800873 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100874 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700875 Enabled scanning of DMI to identify machine quirks. Say Y
876 here unless you have verified that your setup is not
877 affected by entries in the DMI blacklist. Required by PNP
878 BIOS code.
879
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100880config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700881 bool "Old AMD GART IOMMU support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100882 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200883 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100884 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200885 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
886 GART based hardware IOMMUs.
887
888 The GART supports full DMA access for devices with 32-bit access
889 limitations, on systems with more than 3 GB. This is usually needed
890 for USB, sound, many IDE/SATA chipsets and some other devices.
891
892 Newer systems typically have a modern AMD IOMMU, supported via
893 the CONFIG_AMD_IOMMU=y config option.
894
895 In normal configurations this driver is only active when needed:
896 there's more than 3 GB of memory and the system contains a
897 32-bit limited device.
898
899 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100900
901config CALGARY_IOMMU
902 bool "IBM Calgary IOMMU support"
903 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700904 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100905 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100906 Support for hardware IOMMUs in IBM's xSeries x366 and x460
907 systems. Needed to run systems with more than 3GB of memory
908 properly with 32-bit PCI devices that do not support DAC
909 (Double Address Cycle). Calgary also supports bus level
910 isolation, where all DMAs pass through the IOMMU. This
911 prevents them from going anywhere except their intended
912 destination. This catches hard-to-find kernel bugs and
913 mis-behaving drivers and devices that do not use the DMA-API
914 properly to set up their DMA buffers. The IOMMU can be
915 turned off at boot time with the iommu=off parameter.
916 Normally the kernel will make the right choice by itself.
917 If unsure, say Y.
918
919config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100920 def_bool y
921 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100922 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100923 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100924 Should Calgary be enabled by default? if you choose 'y', Calgary
925 will be used (if it exists). If you choose 'n', Calgary will not be
926 used even if it exists. If you choose 'n' and would like to use
927 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
928 If unsure, say Y.
929
930# need this always selected by IOMMU for the VIA workaround
931config SWIOTLB
Joerg Roedela1afd012008-11-18 12:44:21 +0100932 def_bool y if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100933 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100934 Support for software bounce buffers used on x86-64 systems
Joe Millenbach4454d322012-09-02 17:38:20 -0700935 which don't have a hardware IOMMU. Using this PCI devices
936 which can only access 32-bits of memory can be used on systems
937 with more than 3 GB of memory.
938 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100939
FUJITA Tomonoria8522502008-04-29 00:59:36 -0700940config IOMMU_HELPER
Jan Beulich3120e252012-09-10 12:41:45 +0100941 def_bool y
942 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
Linus Torvaldsd25e26b2008-08-25 14:15:38 -0700943
Mike Travis1184dc22008-05-12 21:21:12 +0200944config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200945 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700946 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800947 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100948 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200949 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200950 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100951
952config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800953 int "Maximum number of CPUs" if SMP && !MAXSMP
Michael K. Johnson2a3313f2009-04-21 21:44:48 -0400954 range 2 8 if SMP && X86_32 && !X86_BIGSMP
Thomas Gleixner7bbcbd32017-12-20 18:02:34 +0100955 range 2 64 if SMP && X86_32 && X86_BIGSMP
956 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK && X86_64
Josh Boyerb53b5ed2013-11-05 09:38:16 -0500957 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
Mike Travis78637a972008-12-16 17:34:00 -0800958 default "1" if !SMP
Josh Boyerb53b5ed2013-11-05 09:38:16 -0500959 default "8192" if MAXSMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800960 default "32" if SMP && X86_BIGSMP
Kirill A. Shutemovc5c19942015-05-08 13:25:45 +0300961 default "8" if SMP && X86_32
962 default "64" if SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100963 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100964 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500965 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +0300966 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100967 minimum value which makes sense is 2.
968
969 This is purely to save memory - each supported CPU adds
970 approximately eight kilobytes to the kernel image.
971
972config SCHED_SMT
973 bool "SMT (Hyperthreading) scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +0200974 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100975 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100976 SMT scheduler support improves the CPU scheduler's decision making
977 when dealing with Intel Pentium 4 chips with HyperThreading at a
978 cost of slightly increased overhead in some places. If unsure say
979 N here.
980
981config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100982 def_bool y
983 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +0200984 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100985 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100986 Multi-core scheduler support improves the CPU scheduler's decision
987 making when dealing with multi-core CPU chips at a cost of slightly
988 increased overhead in some places. If unsure say N here.
989
Tim Chende966cf2016-11-29 10:43:27 -0800990config SCHED_MC_PRIO
991 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +0100992 depends on SCHED_MC && CPU_SUP_INTEL
993 select X86_INTEL_PSTATE
994 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -0800995 default y
Tim Chen5e76b2a2016-11-22 12:23:55 -0800996 ---help---
Ingo Molnar0a21fc12016-11-30 08:33:54 +0100997 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
998 core ordering determined at manufacturing time, which allows
999 certain cores to reach higher turbo frequencies (when running
1000 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001001
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001002 Enabling this kernel feature teaches the scheduler about
1003 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1004 scheduler's CPU selection logic accordingly, so that higher
1005 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001006
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001007 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001008
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001009 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001010
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001011source "kernel/Kconfig.preempt"
1012
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001013config UP_LATE_INIT
1014 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +01001015 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001016
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001017config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001018 bool "Local APIC support on uniprocessors" if !PCI_MSI
1019 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001020 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001021 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001022 A local APIC (Advanced Programmable Interrupt Controller) is an
1023 integrated interrupt controller in the CPU. If you have a single-CPU
1024 system which has a processor with a local APIC, you can say Y here to
1025 enable and use it. If you say Y here even though your machine doesn't
1026 have a local APIC, then the kernel will still run with no slowdown at
1027 all. The local APIC supports CPU-generated self-interrupts (timer,
1028 performance counters), and the NMI watchdog which detects hard
1029 lockups.
1030
1031config X86_UP_IOAPIC
1032 bool "IO-APIC support on uniprocessors"
1033 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001034 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001035 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1036 SMP-capable replacement for PC-style interrupt controllers. Most
1037 SMP systems and many recent uniprocessor systems have one.
1038
1039 If you have a single-CPU system with an IO-APIC, you can say Y here
1040 to use it. If you say Y here even though your machine doesn't have
1041 an IO-APIC, then the kernel will still run with no slowdown at all.
1042
1043config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001044 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001045 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001046 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001047 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001048
1049config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001050 def_bool y
1051 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001052
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001053config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1054 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001055 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001056 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001057 This option enables a workaround that fixes a source of
1058 spurious interrupts. This is recommended when threaded
1059 interrupt handling is used on systems where the generation of
1060 superfluous "boot interrupts" cannot be disabled.
1061
1062 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1063 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1064 kernel does during interrupt handling). On chipsets where this
1065 boot IRQ generation cannot be disabled, this workaround keeps
1066 the original IRQ line masked so that only the equivalent "boot
1067 IRQ" is delivered to the CPUs. The workaround also tells the
1068 kernel to set up the IRQ handler on the boot IRQ line. In this
1069 way only one interrupt is delivered to the kernel. Otherwise
1070 the spurious second interrupt may cause the kernel to bring
1071 down (vital) interrupt lines.
1072
1073 Only affects "broken" chipsets. Interrupt sharing may be
1074 increased on these systems.
1075
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001076config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001077 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001078 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001079 default y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001080 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +02001081 Machine Check support allows the processor to notify the
1082 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001083 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001084 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001085
Tony Luck5de97c92017-03-27 11:33:03 +02001086config X86_MCELOG_LEGACY
1087 bool "Support for deprecated /dev/mcelog character device"
1088 depends on X86_MCE
1089 ---help---
1090 Enable support for /dev/mcelog which is needed by the old mcelog
1091 userspace logging daemon. Consider switching to the new generation
1092 rasdaemon solution.
1093
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001094config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001095 def_bool y
1096 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001097 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001098 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001099 Additional support for intel specific MCE features such as
1100 the thermal monitor.
1101
1102config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001103 def_bool y
1104 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001105 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001106 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001107 Additional support for AMD specific MCE features such as
1108 the DRAM Error Threshold.
1109
Andi Kleen4efc0672009-04-28 19:07:31 +02001110config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001111 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001112 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001113 ---help---
1114 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001115 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001116 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001117
Andi Kleenb2762682009-02-12 13:49:31 +01001118config X86_MCE_THRESHOLD
1119 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001120 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001121
Andi Kleenea149b32009-04-29 19:31:00 +02001122config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001123 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001124 tristate "Machine check injector support"
1125 ---help---
1126 Provide support for injecting machine checks for testing purposes.
1127 If you don't know what a machine check is and you don't do kernel
1128 QA it is safe to say n.
1129
Andi Kleen4efc0672009-04-28 19:07:31 +02001130config X86_THERMAL_VECTOR
1131 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001132 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001133
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001134source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001135
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001136config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001137 bool "Legacy VM86 support"
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001138 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001139 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001140 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001141 This option allows user programs to put the CPU into V8086
1142 mode, which is an 80286-era approximation of 16-bit real mode.
1143
1144 Some very old versions of X and/or vbetool require this option
1145 for user mode setting. Similarly, DOSEMU will use it if
1146 available to accelerate real mode DOS programs. However, any
1147 recent version of DOSEMU, X, or vbetool should be fully
1148 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001149 fall back to software emulation. Nevertheless, if you are using
1150 a 16-bit DOS program where 16-bit performance matters, vm86
1151 mode might be faster than emulation and you might want to
1152 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001153
Ingo Molnar1e642812015-09-05 08:58:10 +02001154 Note that any app that works on a 64-bit kernel is unlikely to
1155 need this option, as 64-bit kernels don't, and can't, support
1156 V8086 mode. This option is also unrelated to 16-bit protected
1157 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001158
Ingo Molnar1e642812015-09-05 08:58:10 +02001159 Enabling this option increases the complexity of the kernel
1160 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001161
Ingo Molnar1e642812015-09-05 08:58:10 +02001162 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001163
1164config VM86
1165 bool
1166 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001167
1168config X86_16BIT
1169 bool "Enable support for 16-bit segments" if EXPERT
1170 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001171 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001172 ---help---
1173 This option is required by programs like Wine to run 16-bit
1174 protected mode legacy code on x86 processors. Disabling
1175 this option saves about 300 bytes on i386, or around 6K text
1176 plus 16K runtime memory on x86-64,
1177
1178config X86_ESPFIX32
1179 def_bool y
1180 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001181
H. Peter Anvin197725d2014-05-04 10:00:49 -07001182config X86_ESPFIX64
1183 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001184 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001185
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001186config X86_VSYSCALL_EMULATION
1187 bool "Enable vsyscall emulation" if EXPERT
1188 default y
1189 depends on X86_64
1190 ---help---
1191 This enables emulation of the legacy vsyscall page. Disabling
1192 it is roughly equivalent to booting with vsyscall=none, except
1193 that it will also disable the helpful warning if a program
1194 tries to use a vsyscall. With this option set to N, offending
1195 programs will just segfault, citing addresses of the form
1196 0xffffffffff600?00.
1197
1198 This option is required by many programs built before 2013, and
1199 care should be used even with newer programs if set to N.
1200
1201 Disabling this option saves about 7K of kernel size and
1202 possibly 4K of additional runtime pagetable memory.
1203
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001204config TOSHIBA
1205 tristate "Toshiba Laptop support"
1206 depends on X86_32
1207 ---help---
1208 This adds a driver to safely access the System Management Mode of
1209 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1210 not work on models with a Phoenix BIOS. The System Management Mode
1211 is used to set the BIOS and power saving options on Toshiba portables.
1212
1213 For information on utilities to make use of this driver see the
1214 Toshiba Linux utilities web site at:
1215 <http://www.buzzard.org.uk/toshiba/>.
1216
1217 Say Y if you intend to run this kernel on a Toshiba portable.
1218 Say N otherwise.
1219
1220config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001221 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001222 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001223 select SENSORS_DELL_SMM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001224 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001225 This option enables legacy /proc/i8k userspace interface in hwmon
1226 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1227 temperature and allows controlling fan speeds of Dell laptops via
1228 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1229 it reports also power and hotkey status. For fan speed control is
1230 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001231
Pali Rohár039ae582015-05-14 13:16:37 +02001232 Say Y if you intend to run this kernel on old Dell laptops or want to
1233 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001234 Say N otherwise.
1235
1236config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001237 bool "Enable X86 board specific fixups for reboot"
1238 depends on X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001239 ---help---
1240 This enables chipset and/or board specific fixups to be done
1241 in order to get reboot to work correctly. This is only needed on
1242 some combinations of hardware and BIOS. The symptom, for which
1243 this config is intended, is when reboot ends with a stalled/hung
1244 system.
1245
1246 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001247 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001248
1249 Say Y if you want to enable the fixup. Currently, it's safe to
1250 enable this option even if you don't need it.
1251 Say N otherwise.
1252
1253config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001254 bool "CPU microcode loading support"
1255 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001256 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001257 select FW_LOADER
1258 ---help---
1259 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001260 Intel and AMD processors. The Intel support is for the IA32 family,
1261 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1262 AMD support is for families 0x10 and later. You will obviously need
1263 the actual microcode binary data itself which is not shipped with
1264 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001265
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001266 The preferred method to load microcode from a detached initrd is described
1267 in Documentation/x86/early-microcode.txt. For that you need to enable
1268 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1269 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001270
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001271 In addition, you can build the microcode into the kernel. For that you
1272 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1273 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001274
Peter Oruba8d86f392008-07-28 18:44:21 +02001275config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001276 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001277 depends on MICROCODE
1278 default MICROCODE
1279 select FW_LOADER
1280 ---help---
1281 This options enables microcode patch loading support for Intel
1282 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001283
Alanb8989db2014-01-20 18:01:56 +00001284 For the current Intel microcode data package go to
1285 <https://downloadcenter.intel.com> and search for
1286 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001287
Peter Oruba80cc9f12008-07-28 18:44:22 +02001288config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001289 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001290 depends on MICROCODE
1291 select FW_LOADER
1292 ---help---
1293 If you select this option, microcode patch loading support for AMD
1294 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001295
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001296config MICROCODE_OLD_INTERFACE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001297 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001298 depends on MICROCODE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001299
1300config X86_MSR
1301 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001302 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001303 This device gives privileged processes access to the x86
1304 Model-Specific Registers (MSRs). It is a character device with
1305 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1306 MSR accesses are directed to a specific CPU on multi-processor
1307 systems.
1308
1309config X86_CPUID
1310 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001311 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001312 This device gives processes access to the x86 CPUID instruction to
1313 be executed on a specific processor. It is a character device
1314 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1315 /dev/cpu/31/cpuid.
1316
1317choice
1318 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001319 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001320 depends on X86_32
1321
1322config NOHIGHMEM
1323 bool "off"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001324 ---help---
1325 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1326 However, the address space of 32-bit x86 processors is only 4
1327 Gigabytes large. That means that, if you have a large amount of
1328 physical memory, not all of it can be "permanently mapped" by the
1329 kernel. The physical memory that's not permanently mapped is called
1330 "high memory".
1331
1332 If you are compiling a kernel which will never run on a machine with
1333 more than 1 Gigabyte total physical RAM, answer "off" here (default
1334 choice and suitable for most users). This will result in a "3GB/1GB"
1335 split: 3GB are mapped so that each process sees a 3GB virtual memory
1336 space and the remaining part of the 4GB virtual memory space is used
1337 by the kernel to permanently map as much physical memory as
1338 possible.
1339
1340 If the machine has between 1 and 4 Gigabytes physical RAM, then
1341 answer "4GB" here.
1342
1343 If more than 4 Gigabytes is used then answer "64GB" here. This
1344 selection turns Intel PAE (Physical Address Extension) mode on.
1345 PAE implements 3-level paging on IA32 processors. PAE is fully
1346 supported by Linux, PAE mode is implemented on all recent Intel
1347 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1348 then the kernel will not boot on CPUs that don't support PAE!
1349
1350 The actual amount of total physical memory will either be
1351 auto detected or can be forced by using a kernel command line option
1352 such as "mem=256M". (Try "man bootparam" or see the documentation of
1353 your boot loader (lilo or loadlin) about how to pass options to the
1354 kernel at boot time.)
1355
1356 If unsure, say "off".
1357
1358config HIGHMEM4G
1359 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001360 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001361 Select this if you have a 32-bit processor and between 1 and 4
1362 gigabytes of physical RAM.
1363
1364config HIGHMEM64G
1365 bool "64GB"
H. Peter Anvineb068e72012-11-28 11:50:23 -08001366 depends on !M486
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001367 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001368 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001369 Select this if you have a 32-bit processor and more than 4
1370 gigabytes of physical RAM.
1371
1372endchoice
1373
1374choice
David Rientjes6a108a12011-01-20 14:44:16 -08001375 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001376 default VMSPLIT_3G
1377 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001378 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001379 Select the desired split between kernel and user memory.
1380
1381 If the address range available to the kernel is less than the
1382 physical memory installed, the remaining memory will be available
1383 as "high memory". Accessing high memory is a little more costly
1384 than low memory, as it needs to be mapped into the kernel first.
1385 Note that increasing the kernel address space limits the range
1386 available to user programs, making the address space there
1387 tighter. Selecting anything other than the default 3G/1G split
1388 will also likely make your kernel incompatible with binary-only
1389 kernel modules.
1390
1391 If you are not absolutely sure what you are doing, leave this
1392 option alone!
1393
1394 config VMSPLIT_3G
1395 bool "3G/1G user/kernel split"
1396 config VMSPLIT_3G_OPT
1397 depends on !X86_PAE
1398 bool "3G/1G user/kernel split (for full 1G low memory)"
1399 config VMSPLIT_2G
1400 bool "2G/2G user/kernel split"
1401 config VMSPLIT_2G_OPT
1402 depends on !X86_PAE
1403 bool "2G/2G user/kernel split (for full 2G low memory)"
1404 config VMSPLIT_1G
1405 bool "1G/3G user/kernel split"
1406endchoice
1407
1408config PAGE_OFFSET
1409 hex
1410 default 0xB0000000 if VMSPLIT_3G_OPT
1411 default 0x80000000 if VMSPLIT_2G
1412 default 0x78000000 if VMSPLIT_2G_OPT
1413 default 0x40000000 if VMSPLIT_1G
1414 default 0xC0000000
1415 depends on X86_32
1416
1417config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001418 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001419 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001420
1421config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001422 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001423 depends on X86_32 && !HIGHMEM4G
Christian Melki9d99c712015-10-05 17:31:33 +02001424 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001425 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001426 PAE is required for NX support, and furthermore enables
1427 larger swapspace support for non-overcommit purposes. It
1428 has the cost of more pagetable lookup overhead, and also
1429 consumes more pagetable space per process.
1430
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001431config X86_5LEVEL
1432 bool "Enable 5-level page tables support"
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001433 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001434 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001435 depends on X86_64
1436 ---help---
1437 5-level paging enables access to larger address space:
1438 upto 128 PiB of virtual address space and 4 PiB of
1439 physical address space.
1440
1441 It will be supported by future Intel CPUs.
1442
1443 Note: a kernel with this option enabled can only be booted
1444 on machines that support the feature.
1445
1446 See Documentation/x86/x86_64/5level-paging.txt for more
1447 information.
1448
1449 Say N if unsure.
1450
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001451config ARCH_PHYS_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001452 def_bool y
1453 depends on X86_64 || X86_PAE
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001454
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001455config ARCH_DMA_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001456 def_bool y
1457 depends on X86_64 || HIGHMEM64G
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001458
Ingo Molnar10971ab2015-03-05 08:18:23 +01001459config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001460 def_bool y
Levin, Alexander (Sasha Levin)4675ff02017-11-15 17:36:02 -08001461 depends on X86_64 && !DEBUG_PAGEALLOC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001462 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001463 Certain kernel features effectively disable kernel
1464 linear 1 GB mappings (even if the CPU otherwise
1465 supports them), so don't confuse the user by printing
1466 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001467
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001468config ARCH_HAS_MEM_ENCRYPT
1469 def_bool y
1470
1471config AMD_MEM_ENCRYPT
1472 bool "AMD Secure Memory Encryption (SME) support"
1473 depends on X86_64 && CPU_SUP_AMD
1474 ---help---
1475 Say yes to enable support for the encryption of system memory.
1476 This requires an AMD processor that supports Secure Memory
1477 Encryption (SME).
1478
1479config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1480 bool "Activate AMD Secure Memory Encryption (SME) by default"
1481 default y
1482 depends on AMD_MEM_ENCRYPT
1483 ---help---
1484 Say yes to have system memory encrypted by default if running on
1485 an AMD processor that supports Secure Memory Encryption (SME).
1486
1487 If set to Y, then the encryption of system memory can be
1488 deactivated with the mem_encrypt=off command line option.
1489
1490 If set to N, then the encryption of system memory can be
1491 activated with the mem_encrypt=on command line option.
1492
Tom Lendackyf88a68f2017-07-17 16:10:09 -05001493config ARCH_USE_MEMREMAP_PROT
1494 def_bool y
1495 depends on AMD_MEM_ENCRYPT
1496
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001497# Common NUMA Features
1498config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001499 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001500 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001501 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1502 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001503 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001504 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001505
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001506 The kernel will try to allocate memory used by a CPU on the
1507 local memory controller of the CPU and add some more
1508 NUMA awareness to the kernel.
1509
Ingo Molnarc280ea52008-11-08 13:29:45 +01001510 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001511 (or later), AMD Opteron, or EM64T NUMA.
1512
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001513 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001514 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001515
1516 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001517
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001518config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001519 def_bool y
1520 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001521 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001522 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001523 Enable AMD NUMA node topology detection. You should say Y here if
1524 you have a multi processor AMD system. This uses an old method to
1525 read the NUMA configuration directly from the builtin Northbridge
1526 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1527 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001528
1529config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001530 def_bool y
1531 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001532 depends on X86_64 && NUMA && ACPI && PCI
1533 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001534 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001535 Enable ACPI SRAT based node topology detection.
1536
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001537# Some NUMA nodes have memory ranges that span
1538# other nodes. Even though a pfn is valid and
1539# between a node's start and end pfns, it may not
1540# reside on that node. See memmap_init_zone()
1541# for details.
1542config NODES_SPAN_OTHER_NODES
1543 def_bool y
1544 depends on X86_64_ACPI_NUMA
1545
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001546config NUMA_EMU
1547 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001548 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001549 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001550 Enable NUMA emulation. A flat machine will be split
1551 into virtual nodes when booted with "numa=fake=N", where N is the
1552 number of nodes. This is only useful for debugging.
1553
1554config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001555 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001556 range 1 10
1557 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001558 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001559 default "3"
1560 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001561 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001562 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001563 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001564
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001565config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001566 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001567 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001568
1569config NEED_NODE_MEMMAP_SIZE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001570 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001571 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001572
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001573config ARCH_FLATMEM_ENABLE
1574 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001575 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001576
1577config ARCH_DISCONTIGMEM_ENABLE
1578 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001579 depends on NUMA && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001580
1581config ARCH_DISCONTIGMEM_DEFAULT
1582 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001583 depends on NUMA && X86_32
1584
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001585config ARCH_SPARSEMEM_ENABLE
1586 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001587 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001588 select SPARSEMEM_STATIC if X86_32
1589 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1590
Tejun Heo3b166512011-04-01 11:15:12 +02001591config ARCH_SPARSEMEM_DEFAULT
1592 def_bool y
1593 depends on X86_64
1594
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001595config ARCH_SELECT_MEMORY_MODEL
1596 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001597 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001598
1599config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001600 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001601 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001602 help
1603 This option enables a sysfs memory/probe interface for testing.
1604 See Documentation/memory-hotplug.txt for more information.
1605 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001606
Tejun Heo3b166512011-04-01 11:15:12 +02001607config ARCH_PROC_KCORE_TEXT
1608 def_bool y
1609 depends on X86_64 && PROC_KCORE
1610
Avi Kivitya29815a2010-01-10 16:28:09 +02001611config ILLEGAL_POINTER_VALUE
1612 hex
1613 default 0 if X86_32
1614 default 0xdead000000000000 if X86_64
1615
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001616source "mm/Kconfig"
1617
Dan Williams7a678322015-08-19 00:34:34 -04001618config X86_PMEM_LEGACY_DEVICE
1619 bool
1620
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001621config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001622 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001623 depends on PHYS_ADDR_T_64BIT
1624 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001625 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001626 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001627 help
1628 Treat memory marked using the non-standard e820 type of 12 as used
1629 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1630 The kernel will offer these regions to the 'pmem' driver so
1631 they can be used for persistent storage.
1632
1633 Say Y if unsure.
1634
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001635config HIGHPTE
1636 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001637 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001638 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001639 The VM uses one page table entry for each page of physical memory.
1640 For systems with a lot of RAM, this can be wasteful of precious
1641 low memory. Setting this option will put user-space page table
1642 entries in high memory.
1643
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001644config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001645 bool "Check for low memory corruption"
1646 ---help---
1647 Periodically check for memory corruption in low memory, which
1648 is suspected to be caused by BIOS. Even when enabled in the
1649 configuration, it is disabled at runtime. Enable it by
1650 setting "memory_corruption_check=1" on the kernel command
1651 line. By default it scans the low 64k of memory every 60
1652 seconds; see the memory_corruption_check_size and
1653 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001654 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001655
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001656 When enabled with the default parameters, this option has
1657 almost no overhead, as it reserves a relatively small amount
1658 of memory and scans it infrequently. It both detects corruption
1659 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001660
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001661 It is, however, intended as a diagnostic tool; if repeatable
1662 BIOS-originated corruption always affects the same memory,
1663 you can use memmap= to prevent the kernel from using that
1664 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001665
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001666config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001667 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001668 depends on X86_CHECK_BIOS_CORRUPTION
1669 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001670 ---help---
1671 Set whether the default state of memory_corruption_check is
1672 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001673
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001674config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001675 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1676 default 64
1677 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001678 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001679 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001680
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001681 The first page contains BIOS data structures that the kernel
1682 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001683
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001684 By default we reserve the first 64K of physical RAM, as a
1685 number of BIOSes are known to corrupt that memory range
1686 during events such as suspend/resume or monitor cable
1687 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001688
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001689 You can set this to 4 if you are absolutely sure that you
1690 trust the BIOS to get all its memory reservations and usages
1691 right. If you know your BIOS have problems beyond the
1692 default 64K area, you can set this to 640 to avoid using the
1693 entire low memory range.
1694
1695 If you have doubts about the BIOS (e.g. suspend/resume does
1696 not work or there's kernel crashes after certain hardware
1697 hotplug events) then you might want to enable
1698 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1699 typical corruption patterns.
1700
1701 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001702
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001703config MATH_EMULATION
1704 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001705 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001706 prompt "Math emulation" if X86_32
1707 ---help---
1708 Linux can emulate a math coprocessor (used for floating point
1709 operations) if you don't have one. 486DX and Pentium processors have
1710 a math coprocessor built in, 486SX and 386 do not, unless you added
1711 a 487DX or 387, respectively. (The messages during boot time can
1712 give you some hints here ["man dmesg"].) Everyone needs either a
1713 coprocessor or this emulation.
1714
1715 If you don't have a math coprocessor, you need to say Y here; if you
1716 say Y here even though you have a coprocessor, the coprocessor will
1717 be used nevertheless. (This behavior can be changed with the kernel
1718 command line option "no387", which comes handy if your coprocessor
1719 is broken. Try "man bootparam" or see the documentation of your boot
1720 loader (lilo or loadlin) about how to pass options to the kernel at
1721 boot time.) This means that it is a good idea to say Y here if you
1722 intend to use this kernel on different machines.
1723
1724 More information about the internals of the Linux math coprocessor
1725 emulation can be found in <file:arch/x86/math-emu/README>.
1726
1727 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1728 kernel, it won't hurt.
1729
1730config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001731 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001732 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001733 ---help---
1734 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1735 the Memory Type Range Registers (MTRRs) may be used to control
1736 processor access to memory ranges. This is most useful if you have
1737 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1738 allows bus write transfers to be combined into a larger transfer
1739 before bursting over the PCI/AGP bus. This can increase performance
1740 of image write operations 2.5 times or more. Saying Y here creates a
1741 /proc/mtrr file which may be used to manipulate your processor's
1742 MTRRs. Typically the X server should use this.
1743
1744 This code has a reasonably generic interface so that similar
1745 control registers on other processors can be easily supported
1746 as well:
1747
1748 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1749 Registers (ARRs) which provide a similar functionality to MTRRs. For
1750 these, the ARRs are used to emulate the MTRRs.
1751 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1752 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1753 write-combining. All of these processors are supported by this code
1754 and it makes sense to say Y here if you have one of them.
1755
1756 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1757 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1758 can lead to all sorts of problems, so it's good to say Y here.
1759
1760 You can safely say Y even if your machine doesn't have MTRRs, you'll
1761 just add about 9 KB to your kernel.
1762
Randy Dunlap7225e752008-07-26 17:54:22 -07001763 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001764
Yinghai Lu95ffa242008-04-29 03:52:33 -07001765config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001766 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001767 prompt "MTRR cleanup support"
1768 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001769 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001770 Convert MTRR layout from continuous to discrete, so X drivers can
1771 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001772
Thomas Gleixneraba37282008-07-15 14:48:48 +02001773 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001774 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001775 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001776
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001777 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001778
1779config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001780 int "MTRR cleanup enable value (0-1)"
1781 range 0 1
1782 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001783 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001784 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001785 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001786
Yinghai Lu12031a62008-05-02 02:40:22 -07001787config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1788 int "MTRR cleanup spare reg num (0-7)"
1789 range 0 7
1790 default "1"
1791 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001792 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001793 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001794 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001795
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001796config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001797 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001798 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001799 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001800 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001801 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001802
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001803 PATs are the modern equivalents of MTRRs and are much more
1804 flexible than MTRRs.
1805
1806 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001807 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001808
1809 If unsure, say Y.
1810
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001811config ARCH_USES_PG_UNCACHED
1812 def_bool y
1813 depends on X86_PAT
1814
H. Peter Anvin628c6242011-07-31 13:59:29 -07001815config ARCH_RANDOM
1816 def_bool y
1817 prompt "x86 architectural random number generator" if EXPERT
1818 ---help---
1819 Enable the x86 architectural RDRAND instruction
1820 (Intel Bull Mountain technology) to generate random numbers.
1821 If supported, this is a high bandwidth, cryptographically
1822 secure hardware random number generator.
1823
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001824config X86_SMAP
1825 def_bool y
1826 prompt "Supervisor Mode Access Prevention" if EXPERT
1827 ---help---
1828 Supervisor Mode Access Prevention (SMAP) is a security
1829 feature in newer Intel processors. There is a small
1830 performance cost if this enabled and turned on; there is
1831 also a small increase in the kernel size if this is enabled.
1832
1833 If unsure, say Y.
1834
Ricardo Neriaa35f892017-11-05 18:27:54 -08001835config X86_INTEL_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001836 def_bool y
Ricardo Neriaa35f892017-11-05 18:27:54 -08001837 depends on CPU_SUP_INTEL
1838 prompt "Intel User Mode Instruction Prevention" if EXPERT
1839 ---help---
1840 The User Mode Instruction Prevention (UMIP) is a security
1841 feature in newer Intel processors. If enabled, a general
Ricardo Neri796ebc82017-11-13 22:29:42 -08001842 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1843 or STR instructions are executed in user mode. These instructions
1844 unnecessarily expose information about the hardware state.
1845
1846 The vast majority of applications do not use these instructions.
1847 For the very few that do, software emulation is provided in
1848 specific cases in protected and virtual-8086 modes. Emulated
1849 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001850
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001851config X86_INTEL_MPX
1852 prompt "Intel MPX (Memory Protection Extensions)"
1853 def_bool n
Rik van Rieldf3735c2017-09-06 16:25:11 -07001854 # Note: only available in 64-bit mode due to VMA flags shortage
1855 depends on CPU_SUP_INTEL && X86_64
1856 select ARCH_USES_HIGH_VMA_FLAGS
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001857 ---help---
1858 MPX provides hardware features that can be used in
1859 conjunction with compiler-instrumented code to check
1860 memory references. It is designed to detect buffer
1861 overflow or underflow bugs.
1862
1863 This option enables running applications which are
1864 instrumented or otherwise use MPX. It does not use MPX
1865 itself inside the kernel or to protect the kernel
1866 against bad memory references.
1867
1868 Enabling this option will make the kernel larger:
1869 ~8k of kernel text and 36 bytes of data on a 64-bit
1870 defconfig. It adds a long to the 'mm_struct' which
1871 will increase the kernel memory overhead of each
1872 process and adds some branches to paths used during
1873 exec() and munmap().
1874
1875 For details, see Documentation/x86/intel_mpx.txt
1876
1877 If unsure, say N.
1878
Dave Hansen35e97792016-02-12 13:02:00 -08001879config X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001880 prompt "Intel Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001881 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001882 # Note: only available in 64-bit mode
Dave Hansen35e97792016-02-12 13:02:00 -08001883 depends on CPU_SUP_INTEL && X86_64
Ingo Molnar52c8e602016-11-15 10:15:03 +01001884 select ARCH_USES_HIGH_VMA_FLAGS
1885 select ARCH_HAS_PKEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001886 ---help---
1887 Memory Protection Keys provides a mechanism for enforcing
1888 page-based protections, but without requiring modification of the
1889 page tables when an application changes protection domains.
1890
1891 For details, see Documentation/x86/protection-keys.txt
1892
1893 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001894
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001895config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001896 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001897 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001898 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001899 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001900 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001901 This enables the kernel to use EFI runtime services that are
1902 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001903
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001904 This option is only useful on systems that have EFI firmware.
1905 In addition, you should use the latest ELILO loader available
1906 at <http://elilo.sourceforge.net> in order to take advantage
1907 of EFI runtime services. However, even with this option, the
1908 resultant kernel should continue to boot on existing non-EFI
1909 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001910
Matt Fleming291f3632011-12-12 21:27:52 +00001911config EFI_STUB
1912 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001913 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001914 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001915 ---help---
1916 This kernel feature allows a bzImage to be loaded directly
1917 by EFI firmware without the use of a bootloader.
1918
Roy Franz4172fe22013-09-22 15:45:25 -07001919 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001920
Matt Fleming7d453ee2014-01-10 18:52:06 +00001921config EFI_MIXED
1922 bool "EFI mixed-mode support"
1923 depends on EFI_STUB && X86_64
1924 ---help---
1925 Enabling this feature allows a 64-bit kernel to be booted
1926 on a 32-bit firmware, provided that your CPU supports 64-bit
1927 mode.
1928
1929 Note that it is not possible to boot a mixed-mode enabled
1930 kernel via the EFI boot stub - a bootloader that supports
1931 the EFI handover protocol must be used.
1932
1933 If unsure, say N.
1934
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001935config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001936 def_bool y
1937 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001938 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001939 This kernel feature is useful for number crunching applications
1940 that may need to compute untrusted bytecode during their
1941 execution. By using pipes or other transports made available to
1942 the process as file descriptors supporting the read/write
1943 syscalls, it's possible to isolate those applications in
1944 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001945 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001946 and the task is only allowed to execute a few safe syscalls
1947 defined by each seccomp mode.
1948
1949 If unsure, say Y. Only embedded should say N here.
1950
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001951source kernel/Kconfig.hz
1952
1953config KEXEC
1954 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001955 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001956 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001957 kexec is a system call that implements the ability to shutdown your
1958 current kernel, and to start another kernel. It is like a reboot
1959 but it is independent of the system firmware. And like a reboot
1960 you can start any kernel with it, not just Linux.
1961
1962 The name comes from the similarity to the exec system call.
1963
1964 It is an ongoing process to be certain the hardware in a machine
1965 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001966 initially work for you. As of this writing the exact hardware
1967 interface is strongly in flux, so no good recommendation can be
1968 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001969
Vivek Goyal74ca3172014-08-29 15:18:46 -07001970config KEXEC_FILE
1971 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07001972 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07001973 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07001974 depends on X86_64
1975 depends on CRYPTO=y
1976 depends on CRYPTO_SHA256=y
1977 ---help---
1978 This is new version of kexec system call. This system call is
1979 file based and takes file descriptors as system call argument
1980 for kernel and initramfs as opposed to list of segments as
1981 accepted by previous system call.
1982
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001983config KEXEC_VERIFY_SIG
1984 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07001985 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001986 ---help---
1987 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01001988 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001989
Borislav Petkovd8eb8942015-03-13 14:04:37 +01001990 In addition to that option, you need to enable signature
1991 verification for the corresponding kernel image type being
1992 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001993
1994config KEXEC_BZIMAGE_VERIFY_SIG
1995 bool "Enable bzImage signature verification support"
1996 depends on KEXEC_VERIFY_SIG
1997 depends on SIGNED_PE_FILE_VERIFICATION
1998 select SYSTEM_TRUSTED_KEYRING
1999 ---help---
2000 Enable bzImage signature verification support.
2001
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002002config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002003 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002004 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002005 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002006 Generate crash dump after being started by kexec.
2007 This should be normally only set in special crash dump kernels
2008 which are loaded in the main kernel with kexec-tools into
2009 a specially reserved region and then later executed after
2010 a crash by kdump/kexec. The crash dump kernel must be compiled
2011 to a memory address not used by the main kernel or BIOS using
2012 PHYSICAL_START, or it must be built as a relocatable image
2013 (CONFIG_RELOCATABLE=y).
2014 For more details see Documentation/kdump/kdump.txt
2015
Huang Ying3ab83522008-07-25 19:45:07 -07002016config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002017 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002018 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002019 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07002020 Jump between original kernel and kexeced kernel and invoke
2021 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002022
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002023config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002024 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002025 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002026 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002027 This gives the physical address where the kernel is loaded.
2028
2029 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2030 bzImage will decompress itself to above physical address and
2031 run from there. Otherwise, bzImage will run from the address where
2032 it has been loaded by the boot loader and will ignore above physical
2033 address.
2034
2035 In normal kdump cases one does not have to set/change this option
2036 as now bzImage can be compiled as a completely relocatable image
2037 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2038 address. This option is mainly useful for the folks who don't want
2039 to use a bzImage for capturing the crash dump and want to use a
2040 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2041 to be specifically compiled to run from a specific memory area
2042 (normally a reserved region) and this option comes handy.
2043
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002044 So if you are using bzImage for capturing the crash dump,
2045 leave the value here unchanged to 0x1000000 and set
2046 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2047 for capturing the crash dump change this value to start of
2048 the reserved region. In other words, it can be set based on
2049 the "X" value as specified in the "crashkernel=YM@XM"
2050 command line boot parameter passed to the panic-ed
2051 kernel. Please take a look at Documentation/kdump/kdump.txt
2052 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002053
2054 Usage of bzImage for capturing the crash dump is recommended as
2055 one does not have to build two kernels. Same kernel can be used
2056 as production kernel and capture kernel. Above option should have
2057 gone away after relocatable bzImage support is introduced. But it
2058 is present because there are users out there who continue to use
2059 vmlinux for dump capture. This option should go away down the
2060 line.
2061
2062 Don't change this unless you know what you are doing.
2063
2064config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002065 bool "Build a relocatable kernel"
2066 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002067 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002068 This builds a kernel image that retains relocation information
2069 so it can be loaded someplace besides the default 1MB.
2070 The relocations tend to make the kernel binary about 10% larger,
2071 but are discarded at runtime.
2072
2073 One use is for the kexec on panic case where the recovery kernel
2074 must live at a different physical address than the primary
2075 kernel.
2076
2077 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2078 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002079 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002080
Kees Cook8ab38202013-10-10 17:18:14 -07002081config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002082 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002083 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002084 default y
Kees Cook8ab38202013-10-10 17:18:14 -07002085 ---help---
Baoquan Hee8581e32016-04-20 13:55:43 -07002086 In support of Kernel Address Space Layout Randomization (KASLR),
2087 this randomizes the physical address at which the kernel image
2088 is decompressed and the virtual address where the kernel
2089 image is mapped, as a security feature that deters exploit
2090 attempts relying on knowledge of the location of kernel
2091 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002092
Kees Cooked9f0072016-05-25 15:45:33 -07002093 On 64-bit, the kernel physical and virtual addresses are
2094 randomized separately. The physical address will be anywhere
2095 between 16MB and the top of physical memory (up to 64TB). The
2096 virtual address will be randomized from 16MB up to 1GB (9 bits
2097 of entropy). Note that this also reduces the memory space
2098 available to kernel modules from 1.5GB to 1GB.
2099
2100 On 32-bit, the kernel physical and virtual addresses are
2101 randomized together. They will be randomized from 16MB up to
2102 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002103
Baoquan Hee8581e32016-04-20 13:55:43 -07002104 Entropy is generated using the RDRAND instruction if it is
2105 supported. If RDTSC is supported, its value is mixed into
2106 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002107 supported, then entropy is read from the i8254 timer. The
2108 usable entropy is limited by the kernel being built using
2109 2GB addressing, and that PHYSICAL_ALIGN must be at a
2110 minimum of 2MB. As a result, only 10 bits of entropy are
2111 theoretically possible, but the implementations are further
2112 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002113
Ingo Molnar6807c842017-04-18 11:08:12 +02002114 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002115
2116# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002117config X86_NEED_RELOCS
2118 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002119 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002120
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002121config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002122 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002123 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002124 range 0x2000 0x1000000 if X86_32
2125 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002126 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002127 This value puts the alignment restrictions on physical address
2128 where kernel is loaded and run from. Kernel is compiled for an
2129 address which meets above alignment restriction.
2130
2131 If bootloader loads the kernel at a non-aligned address and
2132 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2133 address aligned to above value and run from there.
2134
2135 If bootloader loads the kernel at a non-aligned address and
2136 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2137 load address and decompress itself to the address it has been
2138 compiled for and run from there. The address for which kernel is
2139 compiled already meets above alignment restrictions. Hence the
2140 end result is that kernel runs from a physical address meeting
2141 above alignment restrictions.
2142
Kees Cooka0215062013-07-08 09:15:17 -07002143 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2144 this value must be a multiple of 0x200000.
2145
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002146 Don't change this unless you know what you are doing.
2147
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002148config DYNAMIC_MEMORY_LAYOUT
2149 bool
2150 ---help---
2151 This option makes base addresses of vmalloc and vmemmap as well as
2152 __PAGE_OFFSET movable during boot.
2153
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002154config RANDOMIZE_MEMORY
2155 bool "Randomize the kernel memory sections"
2156 depends on X86_64
2157 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002158 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002159 default RANDOMIZE_BASE
2160 ---help---
2161 Randomizes the base virtual address of kernel memory sections
2162 (physical memory mapping, vmalloc & vmemmap). This security feature
2163 makes exploits relying on predictable memory locations less reliable.
2164
2165 The order of allocations remains unchanged. Entropy is generated in
2166 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2167 configuration have in average 30,000 different possible virtual
2168 addresses for each memory section.
2169
Ingo Molnar6807c842017-04-18 11:08:12 +02002170 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002171
Thomas Garnier90397a42016-06-21 17:47:06 -07002172config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2173 hex "Physical memory mapping padding" if EXPERT
2174 depends on RANDOMIZE_MEMORY
2175 default "0xa" if MEMORY_HOTPLUG
2176 default "0x0"
2177 range 0x1 0x40 if MEMORY_HOTPLUG
2178 range 0x0 0x40
2179 ---help---
2180 Define the padding in terabytes added to the existing physical
2181 memory size during kernel memory randomization. It is useful
2182 for memory hotplug support but reduces the entropy available for
2183 address randomization.
2184
2185 If unsure, leave at the default value.
2186
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002187config HOTPLUG_CPU
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002188 bool "Support for hot-pluggable CPUs"
Stephen Rothwell40b31362013-05-21 13:49:35 +10002189 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002190 ---help---
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002191 Say Y here to allow turning CPUs off and on. CPUs can be
2192 controlled through /sys/devices/system/cpu.
2193 ( Note: power management support will enable this option
2194 automatically on SMP systems. )
2195 Say N if you want to disable CPU hotplug.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002196
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002197config BOOTPARAM_HOTPLUG_CPU0
2198 bool "Set default setting of cpu0_hotpluggable"
2199 default n
Kees Cook2c922cd2013-01-22 13:01:19 -08002200 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002201 ---help---
2202 Set whether default state of cpu0_hotpluggable is on or off.
2203
2204 Say Y here to enable CPU0 hotplug by default. If this switch
2205 is turned on, there is no need to give cpu0_hotplug kernel
2206 parameter and the CPU0 hotplug feature is enabled by default.
2207
2208 Please note: there are two known CPU0 dependencies if you want
2209 to enable the CPU0 hotplug feature either by this switch or by
2210 cpu0_hotplug kernel parameter.
2211
2212 First, resume from hibernate or suspend always starts from CPU0.
2213 So hibernate and suspend are prevented if CPU0 is offline.
2214
2215 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2216 offline if any interrupt can not migrate out of CPU0. There may
2217 be other CPU0 dependencies.
2218
2219 Please make sure the dependencies are under your control before
2220 you enable this feature.
2221
2222 Say N if you don't want to enable CPU0 hotplug feature by default.
2223 You still can enable the CPU0 hotplug feature at boot by kernel
2224 parameter cpu0_hotplug.
2225
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002226config DEBUG_HOTPLUG_CPU0
2227 def_bool n
2228 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002229 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002230 ---help---
2231 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2232 soon as possible and boots up userspace with CPU0 offlined. User
2233 can online CPU0 back after boot time.
2234
2235 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2236 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2237 compilation or giving cpu0_hotplug kernel parameter at boot.
2238
2239 If unsure, say N.
2240
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002241config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002242 def_bool n
2243 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002244 depends on COMPAT_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002245 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002246 Certain buggy versions of glibc will crash if they are
2247 presented with a 32-bit vDSO that is not mapped at the address
2248 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002249
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002250 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2251 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2252 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2253 the only released version with the bug, but OpenSUSE 9
2254 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002255
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002256 The symptom of the bug is that everything crashes on startup, saying:
2257 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2258
2259 Saying Y here changes the default value of the vdso32 boot
2260 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2261 This works around the glibc bug but hurts performance.
2262
2263 If unsure, say N: if you are compiling your own kernel, you
2264 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002265
Kees Cook3dc33bd2015-08-12 17:55:19 -07002266choice
2267 prompt "vsyscall table for legacy applications"
2268 depends on X86_64
2269 default LEGACY_VSYSCALL_EMULATE
2270 help
2271 Legacy user code that does not know how to find the vDSO expects
2272 to be able to issue three syscalls by calling fixed addresses in
2273 kernel space. Since this location is not randomized with ASLR,
2274 it can be used to assist security vulnerability exploitation.
2275
2276 This setting can be changed at boot time via the kernel command
2277 line parameter vsyscall=[native|emulate|none].
2278
2279 On a system with recent enough glibc (2.14 or newer) and no
2280 static binaries, you can say None without a performance penalty
2281 to improve security.
2282
2283 If unsure, select "Emulate".
2284
2285 config LEGACY_VSYSCALL_NATIVE
2286 bool "Native"
2287 help
2288 Actual executable code is located in the fixed vsyscall
2289 address mapping, implementing time() efficiently. Since
2290 this makes the mapping executable, it can be used during
2291 security vulnerability exploitation (traditionally as
2292 ROP gadgets). This configuration is not recommended.
2293
2294 config LEGACY_VSYSCALL_EMULATE
2295 bool "Emulate"
2296 help
2297 The kernel traps and emulates calls into the fixed
2298 vsyscall address mapping. This makes the mapping
2299 non-executable, but it still contains known contents,
2300 which could be used in certain rare security vulnerability
2301 exploits. This configuration is recommended when userspace
2302 still uses the vsyscall area.
2303
2304 config LEGACY_VSYSCALL_NONE
2305 bool "None"
2306 help
2307 There will be no vsyscall mapping at all. This will
2308 eliminate any risk of ASLR bypass due to the vsyscall
2309 fixed address mapping. Attempts to use the vsyscalls
2310 will be reported to dmesg, so that either old or
2311 malicious userspace programs can be identified.
2312
2313endchoice
2314
Tim Bird516cbf32008-08-12 12:52:36 -07002315config CMDLINE_BOOL
2316 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002317 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002318 Allow for specifying boot arguments to the kernel at
2319 build time. On some systems (e.g. embedded ones), it is
2320 necessary or convenient to provide some or all of the
2321 kernel boot arguments with the kernel itself (that is,
2322 to not rely on the boot loader to provide them.)
2323
2324 To compile command line arguments into the kernel,
2325 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002326 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002327
2328 Systems with fully functional boot loaders (i.e. non-embedded)
2329 should leave this option set to 'N'.
2330
2331config CMDLINE
2332 string "Built-in kernel command string"
2333 depends on CMDLINE_BOOL
2334 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002335 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002336 Enter arguments here that should be compiled into the kernel
2337 image and used at boot time. If the boot loader provides a
2338 command line at boot time, it is appended to this string to
2339 form the full kernel command line, when the system boots.
2340
2341 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2342 change this behavior.
2343
2344 In most cases, the command line (whether built-in or provided
2345 by the boot loader) should specify the device for the root
2346 file system.
2347
2348config CMDLINE_OVERRIDE
2349 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002350 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002351 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002352 Set this option to 'Y' to have the kernel ignore the boot loader
2353 command line, and use ONLY the built-in command line.
2354
2355 This is used to work around broken boot loaders. This should
2356 be set to 'N' under normal conditions.
2357
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002358config MODIFY_LDT_SYSCALL
2359 bool "Enable the LDT (local descriptor table)" if EXPERT
2360 default y
2361 ---help---
2362 Linux can allow user programs to install a per-process x86
2363 Local Descriptor Table (LDT) using the modify_ldt(2) system
2364 call. This is required to run 16-bit or segmented code such as
2365 DOSEMU or some Wine programs. It is also used by some very old
2366 threading libraries.
2367
2368 Enabling this feature adds a small amount of overhead to
2369 context switches and increases the low-level kernel attack
2370 surface. Disabling it removes the modify_ldt(2) system call.
2371
2372 Saying 'N' here may make sense for embedded or server kernels.
2373
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002374source "kernel/livepatch/Kconfig"
2375
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002376endmenu
2377
Michal Hocko3072e412017-09-08 16:11:39 -07002378config ARCH_HAS_ADD_PAGES
2379 def_bool y
2380 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2381
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002382config ARCH_ENABLE_MEMORY_HOTPLUG
2383 def_bool y
2384 depends on X86_64 || (X86_32 && HIGHMEM)
2385
Gary Hade35551052008-10-31 10:52:03 -07002386config ARCH_ENABLE_MEMORY_HOTREMOVE
2387 def_bool y
2388 depends on MEMORY_HOTPLUG
2389
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002390config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002391 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002392 depends on NUMA
2393
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002394config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2395 def_bool y
2396 depends on X86_64 || X86_PAE
2397
Naoya Horiguchic177c812014-06-04 16:05:35 -07002398config ARCH_ENABLE_HUGEPAGE_MIGRATION
2399 def_bool y
2400 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2401
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002402config ARCH_ENABLE_THP_MIGRATION
2403 def_bool y
2404 depends on X86_64 && TRANSPARENT_HUGEPAGE
2405
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002406menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002407
2408config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002409 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002410 depends on X86_64 && HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002411
2412source "kernel/power/Kconfig"
2413
2414source "drivers/acpi/Kconfig"
2415
Feng Tangefafc8b2009-08-14 15:23:29 -04002416source "drivers/sfi/Kconfig"
2417
Andi Kleena6b68072008-01-30 13:32:49 +01002418config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002419 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002420 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002421
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002422menuconfig APM
2423 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002424 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002425 ---help---
2426 APM is a BIOS specification for saving power using several different
2427 techniques. This is mostly useful for battery powered laptops with
2428 APM compliant BIOSes. If you say Y here, the system time will be
2429 reset after a RESUME operation, the /proc/apm device will provide
2430 battery status information, and user-space programs will receive
2431 notification of APM "events" (e.g. battery status change).
2432
2433 If you select "Y" here, you can disable actual use of the APM
2434 BIOS by passing the "apm=off" option to the kernel at boot time.
2435
2436 Note that the APM support is almost completely disabled for
2437 machines with more than one CPU.
2438
2439 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002440 and more information, read <file:Documentation/power/apm-acpi.txt>
2441 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002442 <http://www.tldp.org/docs.html#howto>.
2443
2444 This driver does not spin down disk drives (see the hdparm(8)
2445 manpage ("man 8 hdparm") for that), and it doesn't turn off
2446 VESA-compliant "green" monitors.
2447
2448 This driver does not support the TI 4000M TravelMate and the ACER
2449 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2450 desktop machines also don't have compliant BIOSes, and this driver
2451 may cause those machines to panic during the boot phase.
2452
2453 Generally, if you don't have a battery in your machine, there isn't
2454 much point in using this driver and you should say N. If you get
2455 random kernel OOPSes or reboots that don't seem to be related to
2456 anything, try disabling/enabling this option (or disabling/enabling
2457 APM in your BIOS).
2458
2459 Some other things you should try when experiencing seemingly random,
2460 "weird" problems:
2461
2462 1) make sure that you have enough swap space and that it is
2463 enabled.
2464 2) pass the "no-hlt" option to the kernel
2465 3) switch on floating point emulation in the kernel and pass
2466 the "no387" option to the kernel
2467 4) pass the "floppy=nodma" option to the kernel
2468 5) pass the "mem=4M" option to the kernel (thereby disabling
2469 all but the first 4 MB of RAM)
2470 6) make sure that the CPU is not over clocked.
2471 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2472 8) disable the cache from your BIOS settings
2473 9) install a fan for the video card or exchange video RAM
2474 10) install a better fan for the CPU
2475 11) exchange RAM chips
2476 12) exchange the motherboard.
2477
2478 To compile this driver as a module, choose M here: the
2479 module will be called apm.
2480
2481if APM
2482
2483config APM_IGNORE_USER_SUSPEND
2484 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002485 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002486 This option will ignore USER SUSPEND requests. On machines with a
2487 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2488 series notebooks, it is necessary to say Y because of a BIOS bug.
2489
2490config APM_DO_ENABLE
2491 bool "Enable PM at boot time"
2492 ---help---
2493 Enable APM features at boot time. From page 36 of the APM BIOS
2494 specification: "When disabled, the APM BIOS does not automatically
2495 power manage devices, enter the Standby State, enter the Suspend
2496 State, or take power saving steps in response to CPU Idle calls."
2497 This driver will make CPU Idle calls when Linux is idle (unless this
2498 feature is turned off -- see "Do CPU IDLE calls", below). This
2499 should always save battery power, but more complicated APM features
2500 will be dependent on your BIOS implementation. You may need to turn
2501 this option off if your computer hangs at boot time when using APM
2502 support, or if it beeps continuously instead of suspending. Turn
2503 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2504 T400CDT. This is off by default since most machines do fine without
2505 this feature.
2506
2507config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002508 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002509 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002510 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002511 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2512 On some machines, this can activate improved power savings, such as
2513 a slowed CPU clock rate, when the machine is idle. These idle calls
2514 are made after the idle loop has run for some length of time (e.g.,
2515 333 mS). On some machines, this will cause a hang at boot time or
2516 whenever the CPU becomes idle. (On machines with more than one CPU,
2517 this option does nothing.)
2518
2519config APM_DISPLAY_BLANK
2520 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002521 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002522 Enable console blanking using the APM. Some laptops can use this to
2523 turn off the LCD backlight when the screen blanker of the Linux
2524 virtual console blanks the screen. Note that this is only used by
2525 the virtual console screen blanker, and won't turn off the backlight
2526 when using the X Window system. This also doesn't have anything to
2527 do with your VESA-compliant power-saving monitor. Further, this
2528 option doesn't work for all laptops -- it might not turn off your
2529 backlight at all, or it might print a lot of errors to the console,
2530 especially if you are using gpm.
2531
2532config APM_ALLOW_INTS
2533 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002534 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002535 Normally we disable external interrupts while we are making calls to
2536 the APM BIOS as a measure to lessen the effects of a badly behaving
2537 BIOS implementation. The BIOS should reenable interrupts if it
2538 needs to. Unfortunately, some BIOSes do not -- especially those in
2539 many of the newer IBM Thinkpads. If you experience hangs when you
2540 suspend, try setting this to Y. Otherwise, say N.
2541
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002542endif # APM
2543
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002544source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002545
2546source "drivers/cpuidle/Kconfig"
2547
Andy Henroid27471fd2008-10-09 11:45:22 -07002548source "drivers/idle/Kconfig"
2549
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002550endmenu
2551
2552
2553menu "Bus options (PCI etc.)"
2554
2555config PCI
Ingo Molnar1ac97012008-05-19 14:10:14 +02002556 bool "PCI support"
Adrian Bunk1c858082008-01-30 13:32:32 +01002557 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002558 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002559 Find out whether you have a PCI motherboard. PCI is the name of a
2560 bus system, i.e. the way the CPU talks to the other stuff inside
2561 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2562 VESA. If you have PCI, say Y, otherwise N.
2563
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002564choice
2565 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002566 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002567 default PCI_GOANY
2568 ---help---
2569 On PCI systems, the BIOS can be used to detect the PCI devices and
2570 determine their configuration. However, some old PCI motherboards
2571 have BIOS bugs and may crash if this is done. Also, some embedded
2572 PCI-based systems don't have any BIOS at all. Linux can also try to
2573 detect the PCI hardware directly without using the BIOS.
2574
2575 With this option, you can specify how Linux should detect the
2576 PCI devices. If you choose "BIOS", the BIOS will be used,
2577 if you choose "Direct", the BIOS won't be used, and if you
2578 choose "MMConfig", then PCI Express MMCONFIG will be used.
2579 If you choose "Any", the kernel will try MMCONFIG, then the
2580 direct access method and falls back to the BIOS if that doesn't
2581 work. If unsure, go with the default, which is "Any".
2582
2583config PCI_GOBIOS
2584 bool "BIOS"
2585
2586config PCI_GOMMCONFIG
2587 bool "MMConfig"
2588
2589config PCI_GODIRECT
2590 bool "Direct"
2591
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002592config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002593 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002594 depends on OLPC
2595
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002596config PCI_GOANY
2597 bool "Any"
2598
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002599endchoice
2600
2601config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002602 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002603 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002604
2605# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2606config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002607 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002608 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002609
2610config PCI_MMCONFIG
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002611 def_bool y
Feng Tang5f0db7a2009-08-14 15:37:50 -04002612 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002613
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002614config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002615 def_bool y
2616 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002617
Alex Nixonb5401a92010-03-18 16:31:34 -04002618config PCI_XEN
2619 def_bool y
2620 depends on PCI && XEN
2621 select SWIOTLB_XEN
2622
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002623config PCI_DOMAINS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002624 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002625 depends on PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002626
2627config PCI_MMCONFIG
2628 bool "Support mmconfig PCI config space access"
2629 depends on X86_64 && PCI && ACPI
2630
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002631config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002632 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002633 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002634 help
2635 Read the PCI windows out of the CNB20LE host bridge. This allows
2636 PCI hotplug to work on systems with the CNB20LE chipset which do
2637 not have ACPI.
2638
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002639 There's no public spec for this chipset, and this functionality
2640 is known to be incomplete.
2641
2642 You should say N unless you know you need this.
2643
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002644source "drivers/pci/Kconfig"
2645
William Breathitt Gray3a495512016-05-27 18:08:27 -04002646config ISA_BUS
2647 bool "ISA-style bus support on modern systems" if EXPERT
2648 select ISA_BUS_API
2649 help
2650 Enables ISA-style drivers on modern systems. This is necessary to
2651 support PC/104 devices on X86_64 platforms.
2652
2653 If unsure, say N.
2654
David Rientjes1c00f012011-03-22 16:34:59 -07002655# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002656config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002657 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2658 default y
2659 help
2660 Enables ISA-style DMA support for devices requiring such controllers.
2661 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002662
Linus Torvalds51e68d02016-05-21 10:25:19 -07002663if X86_32
2664
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002665config ISA
2666 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002667 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002668 Find out whether you have ISA slots on your motherboard. ISA is the
2669 name of a bus system, i.e. the way the CPU talks to the other stuff
2670 inside your box. Other bus systems are PCI, EISA, MicroChannel
2671 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2672 newer boards don't support it. If you have ISA, say Y, otherwise N.
2673
2674config EISA
2675 bool "EISA support"
2676 depends on ISA
2677 ---help---
2678 The Extended Industry Standard Architecture (EISA) bus was
2679 developed as an open alternative to the IBM MicroChannel bus.
2680
2681 The EISA bus provided some of the features of the IBM MicroChannel
2682 bus while maintaining backward compatibility with cards made for
2683 the older ISA bus. The EISA bus saw limited use between 1988 and
2684 1995 when it was made obsolete by the PCI bus.
2685
2686 Say Y here if you are building a kernel for an EISA-based machine.
2687
2688 Otherwise, say N.
2689
2690source "drivers/eisa/Kconfig"
2691
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002692config SCx200
2693 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002694 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002695 This provides basic support for National Semiconductor's
2696 (now AMD's) Geode processors. The driver probes for the
2697 PCI-IDs of several on-chip devices, so its a good dependency
2698 for other scx200_* drivers.
2699
2700 If compiled as a module, the driver is named scx200.
2701
2702config SCx200HR_TIMER
2703 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002704 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002705 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002706 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002707 This driver provides a clocksource built upon the on-chip
2708 27MHz high-resolution timer. Its also a workaround for
2709 NSC Geode SC-1100's buggy TSC, which loses time when the
2710 processor goes idle (as is done by the scheduler). The
2711 other workaround is idle=poll boot option.
2712
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002713config OLPC
2714 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002715 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002716 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002717 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002718 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002719 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002720 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002721 Add support for detecting the unique features of the OLPC
2722 XO hardware.
2723
Daniel Drakea3128582011-06-25 17:34:10 +01002724config OLPC_XO1_PM
2725 bool "OLPC XO-1 Power Management"
Daniel Drake97c4cb72011-06-25 17:34:11 +01002726 depends on OLPC && MFD_CS5535 && PM_SLEEP
Daniel Drakea3128582011-06-25 17:34:10 +01002727 select MFD_CORE
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002728 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002729 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002730
Daniel Drakecfee9592011-06-25 17:34:17 +01002731config OLPC_XO1_RTC
2732 bool "OLPC XO-1 Real Time Clock"
2733 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2734 ---help---
2735 Add support for the XO-1 real time clock, which can be used as a
2736 programmable wakeup source.
2737
Daniel Drake7feda8e2011-06-25 17:34:12 +01002738config OLPC_XO1_SCI
2739 bool "OLPC XO-1 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002740 depends on OLPC && OLPC_XO1_PM
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002741 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002742 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002743 select GPIO_CS5535
2744 select MFD_CORE
2745 ---help---
2746 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002747 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002748 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002749 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002750 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002751 - AC adapter status updates
2752 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002753
Daniel Drakea0f30f52011-06-25 17:34:18 +01002754config OLPC_XO15_SCI
2755 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002756 depends on OLPC && ACPI
2757 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002758 ---help---
2759 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2760 - EC-driven system wakeups
2761 - AC adapter status updates
2762 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002763
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002764config ALIX
2765 bool "PCEngines ALIX System Support (LED setup)"
2766 select GPIOLIB
2767 ---help---
2768 This option enables system support for the PCEngines ALIX.
2769 At present this just sets up LEDs for GPIO control on
2770 ALIX2/3/6 boards. However, other system specific setup should
2771 get added here.
2772
2773 Note: You must still enable the drivers for GPIO and LED support
2774 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2775
2776 Note: You have to set alix.force=1 for boards with Award BIOS.
2777
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002778config NET5501
2779 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2780 select GPIOLIB
2781 ---help---
2782 This option enables system support for the Soekris Engineering net5501.
2783
Philip A. Prindeville31970592012-01-14 01:45:39 -07002784config GEOS
2785 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2786 select GPIOLIB
2787 depends on DMI
2788 ---help---
2789 This option enables system support for the Traverse Technologies GEOS.
2790
Vivien Didelot7d029122013-01-04 16:18:14 -05002791config TS5500
2792 bool "Technologic Systems TS-5500 platform support"
2793 depends on MELAN
2794 select CHECK_SIGNATURE
2795 select NEW_LEDS
2796 select LEDS_CLASS
2797 ---help---
2798 This option enables system support for the Technologic Systems TS-5500.
2799
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002800endif # X86_32
2801
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002802config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002803 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002804 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002805
2806source "drivers/pcmcia/Kconfig"
2807
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002808config RAPIDIO
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002809 tristate "RapidIO support"
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002810 depends on PCI
2811 default n
2812 help
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002813 If enabled this option will include drivers and the core
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002814 infrastructure code to support RapidIO interconnect devices.
2815
2816source "drivers/rapidio/Kconfig"
2817
David Herrmanne3263ab2013-08-02 14:05:22 +02002818config X86_SYSFB
2819 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2820 help
2821 Firmwares often provide initial graphics framebuffers so the BIOS,
2822 bootloader or kernel can show basic video-output during boot for
2823 user-guidance and debugging. Historically, x86 used the VESA BIOS
2824 Extensions and EFI-framebuffers for this, which are mostly limited
2825 to x86.
2826 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2827 framebuffers so the new generic system-framebuffer drivers can be
2828 used on x86. If the framebuffer is not compatible with the generic
2829 modes, it is adverticed as fallback platform framebuffer so legacy
2830 drivers like efifb, vesafb and uvesafb can pick it up.
2831 If this option is not selected, all system framebuffers are always
2832 marked as fallback platform framebuffers as usual.
2833
2834 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2835 not be able to pick up generic system framebuffers if this option
2836 is selected. You are highly encouraged to enable simplefb as
2837 replacement if you select this option. simplefb can correctly deal
2838 with generic system framebuffers. But you should still keep vesafb
2839 and others enabled as fallback if a system framebuffer is
2840 incompatible with simplefb.
2841
2842 If unsure, say Y.
2843
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002844endmenu
2845
2846
2847menu "Executable file formats / Emulations"
2848
2849source "fs/Kconfig.binfmt"
2850
2851config IA32_EMULATION
2852 bool "IA32 Emulation"
2853 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002854 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002855 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002856 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002857 select COMPAT_OLD_SIGACTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002858 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002859 Include code to run legacy 32-bit programs under a
2860 64-bit kernel. You should likely turn this on, unless you're
2861 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002862
2863config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002864 tristate "IA32 a.out support"
2865 depends on IA32_EMULATION
2866 ---help---
2867 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002868
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002869config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002870 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002871 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002872 ---help---
2873 Include code to run binaries for the x32 native 32-bit ABI
2874 for 64-bit processors. An x32 process gets access to the
2875 full 64-bit register file and wide data path while leaving
2876 pointers at 32 bits for smaller memory footprint.
2877
2878 You will need a recent binutils (2.22 or later) with
2879 elf32_x86_64 support enabled to compile a kernel with this
2880 option set.
2881
Ingo Molnar953fee12016-11-15 10:22:52 +01002882config COMPAT_32
2883 def_bool y
2884 depends on IA32_EMULATION || X86_32
2885 select HAVE_UID16
2886 select OLD_SIGSUSPEND3
2887
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002888config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002889 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002890 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002891
Jan Beulich3120e252012-09-10 12:41:45 +01002892if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002893config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002894 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002895
2896config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002897 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002898 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002899endif
David Howellsee009e4a02011-03-07 15:06:20 +00002900
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002901endmenu
2902
2903
Keith Packarde5beae12008-11-03 18:21:45 +01002904config HAVE_ATOMIC_IOMAP
2905 def_bool y
2906 depends on X86_32
2907
Alessandro Rubini4692d772012-04-04 19:39:58 +02002908config X86_DEV_DMA_OPS
2909 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002910 depends on X86_64 || STA2X11
Alessandro Rubini4692d772012-04-04 19:39:58 +02002911
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002912config X86_DMA_REMAP
2913 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002914 depends on STA2X11
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002915
Kirill A. Shutemove5855132017-06-06 14:31:20 +03002916config HAVE_GENERIC_GUP
2917 def_bool y
2918
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002919source "net/Kconfig"
2920
2921source "drivers/Kconfig"
2922
2923source "drivers/firmware/Kconfig"
2924
2925source "fs/Kconfig"
2926
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002927source "arch/x86/Kconfig.debug"
2928
2929source "security/Kconfig"
2930
2931source "crypto/Kconfig"
2932
Avi Kivityedf88412007-12-16 11:02:48 +02002933source "arch/x86/kvm/Kconfig"
2934
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002935source "lib/Kconfig"