blob: 4faa505ab8ecb0d1d7c45cdff0cf0498f939beae [file] [log] [blame]
Greg Kroah-Hartmanb2441312017-11-01 15:07:57 +01001# SPDX-License-Identifier: GPL-2.0
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01002# Select 32 or 64 bit
3config 64BIT
Sam Ravnborg68409992007-11-17 15:37:31 +01004 bool "64-bit kernel" if ARCH = "x86"
David Woodhouseffee0de2012-12-20 21:51:55 +00005 default ARCH != "i386"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01006 ---help---
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01007 Say yes to build a 64-bit kernel - formerly known as x86_64
8 Say no to build a 32-bit kernel - formerly known as i386
9
10config X86_32
Jan Beulich3120e252012-09-10 12:41:45 +010011 def_bool y
12 depends on !64BIT
Ingo Molnar341c7872016-11-15 10:04:55 +010013 # Options that are inherently 32-bit kernel only:
14 select ARCH_WANT_IPC_PARSE_VERSION
15 select CLKSRC_I8253
16 select CLONE_BACKWARDS
17 select HAVE_AOUT
18 select HAVE_GENERIC_DMA_COHERENT
19 select MODULES_USE_ELF_REL
20 select OLD_SIGACTION
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +010021
22config X86_64
Jan Beulich3120e252012-09-10 12:41:45 +010023 def_bool y
24 depends on 64BIT
Ingo Molnard94e0682016-11-15 10:11:57 +010025 # Options that are inherently 64-bit kernel only:
Aneesh Kumar K.Ve1073d12017-07-06 15:39:17 -070026 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
Ingo Molnard94e0682016-11-15 10:11:57 +010027 select ARCH_SUPPORTS_INT128
28 select ARCH_USE_CMPXCHG_LOCKREF
29 select HAVE_ARCH_SOFT_DIRTY
30 select MODULES_USE_ELF_RELA
31 select X86_DEV_DMA_OPS
Dominik Brodowskif8781c42018-04-05 11:53:05 +020032 select ARCH_HAS_SYSCALL_WRAPPER
Sam Ravnborg1032c0b2007-11-06 21:35:08 +010033
Ingo Molnard94e0682016-11-15 10:11:57 +010034#
35# Arch settings
36#
37# ( Note that options that are marked 'if X86_64' could in principle be
38# ported to 32-bit as well. )
39#
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +010040config X86
Harvey Harrison3c2362e2008-01-30 13:31:03 +010041 def_bool y
Ingo Molnarc763ea22016-11-15 10:26:39 +010042 #
43 # Note: keep this list sorted alphabetically
44 #
Ingo Molnar6471b822015-06-03 10:00:13 +020045 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
46 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
47 select ANON_INODES
48 select ARCH_CLOCKSOURCE_DATA
49 select ARCH_DISCARD_MEMBLOCK
Ingo Molnarc763ea22016-11-15 10:26:39 +010050 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
Laura Abbottfa5b6ec2017-01-10 13:35:40 -080051 select ARCH_HAS_DEBUG_VIRTUAL
Dan Williams21266be2015-11-19 18:19:29 -080052 select ARCH_HAS_DEVMEM_IS_ALLOWED
Ingo Molnar6471b822015-06-03 10:00:13 +020053 select ARCH_HAS_ELF_RANDOMIZE
Linus Torvalds72d93102014-09-13 11:14:53 -070054 select ARCH_HAS_FAST_MULTIPLIER
Dave Hansen316d0972018-04-20 15:20:28 -070055 select ARCH_HAS_FILTER_PGPROT
Daniel Micay6974f0c2017-07-12 14:36:10 -070056 select ARCH_HAS_FORTIFY_SOURCE
Riku Voipio957e3fa2014-12-12 16:57:44 -080057 select ARCH_HAS_GCOV_PROFILE_ALL
Dmitry Vyukov5c9a8752016-03-22 14:27:30 -070058 select ARCH_HAS_KCOV if X86_64
Mathieu Desnoyers10bcc802018-01-29 15:20:18 -050059 select ARCH_HAS_MEMBARRIER_SYNC_CORE
Ingo Molnarc763ea22016-11-15 10:26:39 +010060 select ARCH_HAS_PMEM_API if X86_64
Kees Cook39208aa2017-09-02 13:09:46 -070061 select ARCH_HAS_REFCOUNT
Dan Williams0aed55a2017-05-29 12:22:50 -070062 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Daniel Borkmannd2852a22017-02-21 16:09:33 +010063 select ARCH_HAS_SET_MEMORY
Ingo Molnar6471b822015-06-03 10:00:13 +020064 select ARCH_HAS_SG_CHAIN
Laura Abbottad21fc42017-02-06 16:31:57 -080065 select ARCH_HAS_STRICT_KERNEL_RWX
66 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050067 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Andrey Ryabininc6d30852016-01-20 15:00:55 -080068 select ARCH_HAS_UBSAN_SANITIZE_ALL
Oliver O'Halloran65f7d042017-06-28 11:32:31 +100069 select ARCH_HAS_ZONE_DEVICE if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020070 select ARCH_HAVE_NMI_SAFE_CMPXCHG
71 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040072 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080073 select ARCH_MIGHT_HAVE_PC_SERIO
Ingo Molnar6471b822015-06-03 10:00:13 +020074 select ARCH_SUPPORTS_ATOMIC_RMW
Ingo Molnar6471b822015-06-03 10:00:13 +020075 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
76 select ARCH_USE_BUILTIN_BSWAP
Ingo Molnar6471b822015-06-03 10:00:13 +020077 select ARCH_USE_QUEUED_RWLOCKS
78 select ARCH_USE_QUEUED_SPINLOCKS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -070079 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Ingo Molnarc763ea22016-11-15 10:26:39 +010080 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Huang Ying38d8b4e2017-07-06 15:37:18 -070081 select ARCH_WANTS_THP_SWAP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020082 select BUILDTIME_EXTABLE_SORT
83 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +020084 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
85 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +020086 select DCACHE_WORD_ACCESS
Christoph Hellwigfec777c2018-03-19 11:38:15 +010087 select DMA_DIRECT_OPS
Linus Torvalds45471cd2015-06-24 19:52:06 -070088 select EDAC_ATOMIC_SCRUB
89 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +020090 select GENERIC_CLOCKEVENTS
91 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
92 select GENERIC_CLOCKEVENTS_MIN_ADJUST
93 select GENERIC_CMOS_UPDATE
94 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +010095 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +020096 select GENERIC_EARLY_IOREMAP
97 select GENERIC_FIND_FIRST_BIT
98 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +020099 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +0200100 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +0200101 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200102 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200103 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200104 select GENERIC_IRQ_SHOW
105 select GENERIC_PENDING_IRQ if SMP
106 select GENERIC_SMP_IDLE_THREAD
107 select GENERIC_STRNCPY_FROM_USER
108 select GENERIC_STRNLEN_USER
109 select GENERIC_TIME_VSYSCALL
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200110 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200111 select HAVE_ACPI_APEI if ACPI
112 select HAVE_ACPI_APEI_NMI if ACPI
113 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200114 select HAVE_ARCH_AUDITSYSCALL
115 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
116 select HAVE_ARCH_JUMP_LABEL
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800117 select HAVE_ARCH_KASAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200118 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800119 select HAVE_ARCH_MMAP_RND_BITS if MMU
120 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300121 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ingo Molnar6471b822015-06-03 10:00:13 +0200122 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700123 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Ingo Molnar6471b822015-06-03 10:00:13 +0200124 select HAVE_ARCH_TRACEHOOK
125 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Matthew Wilcoxa00cc7d2017-02-24 14:57:02 -0800126 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
Andy Lutomirskie37e43a2016-08-11 02:35:23 -0700127 select HAVE_ARCH_VMAP_STACK if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100128 select HAVE_ARCH_WITHIN_STACK_FRAMES
Ingo Molnar6471b822015-06-03 10:00:13 +0200129 select HAVE_CC_STACKPROTECTOR
130 select HAVE_CMPXCHG_DOUBLE
131 select HAVE_CMPXCHG_LOCAL
132 select HAVE_CONTEXT_TRACKING if X86_64
Josh Triplettc1bd55f2015-06-30 15:00:00 -0700133 select HAVE_COPY_THREAD_TLS
Ingo Molnar6471b822015-06-03 10:00:13 +0200134 select HAVE_C_RECORDMCOUNT
135 select HAVE_DEBUG_KMEMLEAK
136 select HAVE_DEBUG_STACKOVERFLOW
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700137 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400138 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900139 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Ingo Molnarc763ea22016-11-15 10:26:39 +0100140 select HAVE_EBPF_JIT if X86_64
Johannes Berg58340a02008-07-25 01:45:33 -0700141 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Jiri Slaby5f56a5d2016-05-20 17:00:16 -0700142 select HAVE_EXIT_THREAD
Steven Rostedt (VMware)644e0e82017-03-23 10:33:52 -0400143 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
Ingo Molnar6471b822015-06-03 10:00:13 +0200144 select HAVE_FTRACE_MCOUNT_RECORD
Ingo Molnar6471b822015-06-03 10:00:13 +0200145 select HAVE_FUNCTION_GRAPH_TRACER
146 select HAVE_FUNCTION_TRACER
Emese Revfy6b90bd42016-05-24 00:09:38 +0200147 select HAVE_GCC_PLUGINS
K.Prasad0067f122009-06-01 23:43:57 +0530148 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200149 select HAVE_IDE
150 select HAVE_IOREMAP_PROT
151 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
152 select HAVE_IRQ_TIME_ACCOUNTING
153 select HAVE_KERNEL_BZIP2
154 select HAVE_KERNEL_GZIP
155 select HAVE_KERNEL_LZ4
156 select HAVE_KERNEL_LZMA
157 select HAVE_KERNEL_LZO
158 select HAVE_KERNEL_XZ
159 select HAVE_KPROBES
160 select HAVE_KPROBES_ON_FTRACE
Masami Hiramatsu540adea2018-01-13 02:55:03 +0900161 select HAVE_FUNCTION_ERROR_INJECTION
Ingo Molnar6471b822015-06-03 10:00:13 +0200162 select HAVE_KRETPROBES
163 select HAVE_KVM
164 select HAVE_LIVEPATCH if X86_64
165 select HAVE_MEMBLOCK
166 select HAVE_MEMBLOCK_NODE_MAP
Frederic Weisbecker01027522010-04-11 18:55:56 +0200167 select HAVE_MIXED_BREAKPOINTS_REGS
Josh Poimboeufee9f8fc2017-07-24 18:36:57 -0500168 select HAVE_MOD_ARCH_SPECIFIC
Petr Mladek42a0bb32016-05-20 17:00:33 -0700169 select HAVE_NMI
Ingo Molnar6471b822015-06-03 10:00:13 +0200170 select HAVE_OPROFILE
171 select HAVE_OPTPROBES
172 select HAVE_PCSPKR_PLATFORM
173 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200174 select HAVE_PERF_EVENTS_NMI
Nicholas Piggin92e5aae2017-08-18 15:15:51 -0700175 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
Jiri Olsac5e63192012-08-07 15:20:36 +0200176 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200177 select HAVE_PERF_USER_STACK_DUMP
Vitaly Kuznetsov9e52fc22017-08-28 10:22:51 +0200178 select HAVE_RCU_TABLE_FREE
Ingo Molnar6471b822015-06-03 10:00:13 +0200179 select HAVE_REGS_AND_STACK_ACCESS_API
Josh Poimboeuf11af8472017-10-13 15:02:00 -0500180 select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
Ingo Molnarc763ea22016-11-15 10:26:39 +0100181 select HAVE_STACK_VALIDATION if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200182 select HAVE_SYSCALL_TRACEPOINTS
Ingo Molnar6471b822015-06-03 10:00:13 +0200183 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300184 select HAVE_USER_RETURN_NOTIFIER
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100185 select IRQ_FORCED_THREADING
Thomas Gleixnerdf65c1b2017-03-16 22:50:07 +0100186 select PCI_LOCKLESS_CONFIG
Ingo Molnar6471b822015-06-03 10:00:13 +0200187 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500188 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200189 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200190 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500191 select SRCU
Ingo Molnar6471b822015-06-03 10:00:13 +0200192 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700193 select THREAD_INFO_IN_TASK
Ingo Molnar6471b822015-06-03 10:00:13 +0200194 select USER_STACKTRACE_SUPPORT
195 select VIRT_TO_BUS
Ingo Molnar6471b822015-06-03 10:00:13 +0200196 select X86_FEATURE_NAMES if PROC_FS
Balbir Singh7d8330a2008-02-10 12:46:28 +0530197
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200198config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100199 def_bool y
200 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200201
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700202config OUTPUT_FORMAT
203 string
204 default "elf32-i386" if X86_32
205 default "elf64-x86-64" if X86_64
206
Sam Ravnborg73531902008-05-25 23:03:18 +0200207config ARCH_DEFCONFIG
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200208 string
Sam Ravnborg73531902008-05-25 23:03:18 +0200209 default "arch/x86/configs/i386_defconfig" if X86_32
210 default "arch/x86/configs/x86_64_defconfig" if X86_64
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200211
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100212config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100213 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100214
215config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100216 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100217
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100218config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100219 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100220
Daniel Cashman9e08f572016-01-14 15:20:06 -0800221config ARCH_MMAP_RND_BITS_MIN
222 default 28 if 64BIT
223 default 8
224
225config ARCH_MMAP_RND_BITS_MAX
226 default 32 if 64BIT
227 default 16
228
229config ARCH_MMAP_RND_COMPAT_BITS_MIN
230 default 8
231
232config ARCH_MMAP_RND_COMPAT_BITS_MAX
233 default 16
234
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100235config SBUS
236 bool
237
FUJITA Tomonori3bc4e452010-03-10 15:23:22 -0800238config NEED_DMA_MAP_STATE
Jan Beulich3120e252012-09-10 12:41:45 +0100239 def_bool y
Konrad Rzeszutek Wilka6dfa122015-04-17 15:04:48 -0400240 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
FUJITA Tomonori3bc4e452010-03-10 15:23:22 -0800241
FUJITA Tomonori18e98302010-05-26 14:44:32 -0700242config NEED_SG_DMA_LENGTH
Andrew Morton4a14d842010-05-26 14:44:33 -0700243 def_bool y
FUJITA Tomonori18e98302010-05-26 14:44:32 -0700244
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100245config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100246 def_bool y
247 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100248
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100249config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100250 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100251 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000252 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
253
254config GENERIC_BUG_RELATIVE_POINTERS
255 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100256
257config GENERIC_HWEIGHT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100258 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100259
260config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100261 def_bool y
262 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100263
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100264config RWSEM_XCHGADD_ALGORITHM
Jan Beulich3120e252012-09-10 12:41:45 +0100265 def_bool y
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100266
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100267config GENERIC_CALIBRATE_DELAY
268 def_bool y
269
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800270config ARCH_HAS_CPU_RELAX
271 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100272
Pekka Enberg1b27d052008-04-28 02:12:22 -0700273config ARCH_HAS_CACHE_LINE_SIZE
274 def_bool y
275
Dave Hansen316d0972018-04-20 15:20:28 -0700276config ARCH_HAS_FILTER_PGPROT
277 def_bool y
278
Mike Travisdd5af902008-01-30 13:33:32 +0100279config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900280 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100281
Tejun Heo08fc4582009-08-14 15:00:49 +0900282config NEED_PER_CPU_EMBED_FIRST_CHUNK
283 def_bool y
284
285config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900286 def_bool y
287
Johannes Berg801e4062007-12-08 02:12:39 +0100288config ARCH_HIBERNATION_POSSIBLE
289 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100290
Johannes Bergf4cb5702007-12-08 02:14:00 +0100291config ARCH_SUSPEND_POSSIBLE
292 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100293
Steve Cappercfe28c52013-04-29 14:29:48 +0100294config ARCH_WANT_HUGE_PMD_SHARE
295 def_bool y
296
Steve Capper53313b22013-04-30 08:03:42 +0100297config ARCH_WANT_GENERAL_HUGETLB
298 def_bool y
299
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100300config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000301 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100302
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100303config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000304 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100305
Ingo Molnar765c68b2008-04-09 11:03:37 +0200306config ARCH_SUPPORTS_OPTIMIZED_INLINING
307 def_bool y
308
Akinobu Mita6a11f752009-03-31 15:23:17 -0700309config ARCH_SUPPORTS_DEBUG_PAGEALLOC
310 def_bool y
311
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300312config KASAN_SHADOW_OFFSET
313 hex
314 depends on KASAN
315 default 0xdffffc0000000000
316
Shane Wang69575d32009-09-01 18:25:07 -0700317config HAVE_INTEL_TXT
318 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700319 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700320
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100321config X86_32_SMP
322 def_bool y
323 depends on X86_32 && SMP
324
325config X86_64_SMP
326 def_bool y
327 depends on X86_64 && SMP
328
Tejun Heoccbeed32009-02-09 22:17:40 +0900329config X86_32_LAZY_GS
330 def_bool y
Kees Cook2bc2f682018-02-06 15:37:41 -0800331 depends on X86_32 && CC_STACKPROTECTOR_NONE
Tejun Heoccbeed32009-02-09 22:17:40 +0900332
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530333config ARCH_SUPPORTS_UPROBES
334 def_bool y
335
Rob Herringd20642f2014-04-18 17:19:54 -0500336config FIX_EARLYCON_MEM
337 def_bool y
338
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700339config PGTABLE_LEVELS
340 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300341 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700342 default 4 if X86_64
343 default 3 if X86_PAE
344 default 2
345
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100346source "init/Kconfig"
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700347source "kernel/Kconfig.freezer"
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100348
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100349menu "Processor type and features"
350
Randy Dunlap5ee71532012-01-16 11:57:18 -0800351config ZONE_DMA
352 bool "DMA memory allocation support" if EXPERT
353 default y
354 help
355 DMA memory allocation support allows devices with less than 32-bit
356 addressing to allocate within the first 16MB of address space.
357 Disable if no such devices will be used.
358
359 If unsure, say Y.
360
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100361config SMP
362 bool "Symmetric multi-processing support"
363 ---help---
364 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800365 a system with only one CPU, say N. If you have a system with more
366 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100367
Robert Graffham4a474152014-01-23 15:55:29 -0800368 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100369 machines, but will use only one CPU of a multiprocessor machine. If
370 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800371 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100372 will run faster if you say N here.
373
374 Note that if you say Y here and choose architecture "586" or
375 "Pentium" under "Processor family", the kernel will not work on 486
376 architectures. Similarly, multiprocessor kernels for the "PPro"
377 architecture may not work on all Pentium based boards.
378
379 People using multiprocessor machines who say Y here should also say
380 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
381 Management" code will be disabled if you say Y here.
382
Paul Bolle395cf962011-08-15 02:02:26 +0200383 See also <file:Documentation/x86/i386/IO-APIC.txt>,
Benjamin Petersonc9525a32017-05-20 17:20:16 -0700384 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100385 <http://www.tldp.org/docs.html#howto>.
386
387 If you don't know what to do here, say N.
388
Josh Triplett9def39be2013-10-30 08:09:45 -0700389config X86_FEATURE_NAMES
390 bool "Processor feature human-readable names" if EMBEDDED
391 default y
392 ---help---
393 This option compiles in a table of x86 feature bits and corresponding
394 names. This is required to support /proc/cpuinfo and a few kernel
395 messages. You can disable this to save space, at the expense of
396 making those few kernel messages show numeric feature bits instead.
397
398 If in doubt, say Y.
399
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800400config X86_X2APIC
401 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200402 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800403 ---help---
404 This enables x2apic support on CPUs that have this feature.
405
406 This allows 32-bit apic IDs (so it can support very large systems),
407 and accesses the local apic via MSRs not via mmio.
408
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800409 If you don't know what to do here, say N.
410
Yinghai Lu6695c852008-06-19 12:13:09 -0700411config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700412 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000413 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200414 depends on X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100415 ---help---
Yinghai Lu6695c852008-06-19 12:13:09 -0700416 For old smp systems that do not have proper acpi support. Newer systems
417 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700418
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000419config GOLDFISH
420 def_bool y
421 depends on X86_GOLDFISH
422
David Woodhouse76b04382018-01-11 21:46:25 +0000423config RETPOLINE
424 bool "Avoid speculative indirect branches in kernel"
425 default y
Peter Zijlstrad5028ba2018-02-06 09:46:13 +0100426 select STACK_VALIDATION if HAVE_STACK_VALIDATION
David Woodhouse76b04382018-01-11 21:46:25 +0000427 help
428 Compile kernel with the retpoline compiler options to guard against
429 kernel-to-user data leaks by avoiding speculative indirect
430 branches. Requires a compiler with -mindirect-branch=thunk-extern
431 support for full protection. The kernel may run slower.
432
433 Without compiler support, at least indirect branches in assembler
434 code are eliminated. Since this includes the syscall entry path,
435 it is not entirely pointless.
436
Vikas Shivappaf01d7d512017-07-25 14:14:22 -0700437config INTEL_RDT
438 bool "Intel Resource Director Technology support"
Fenghua Yu78e99b42016-10-22 06:19:53 -0700439 default n
440 depends on X86 && CPU_SUP_INTEL
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100441 select KERNFS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700442 help
Vikas Shivappaf01d7d512017-07-25 14:14:22 -0700443 Select to enable resource allocation and monitoring which are
444 sub-features of Intel Resource Director Technology(RDT). More
445 information about RDT can be found in the Intel x86
446 Architecture Software Developer Manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700447
448 Say N if unsure.
449
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800450if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800451config X86_BIGSMP
452 bool "Support for big SMP systems with more than 8 CPUs"
453 depends on SMP
454 ---help---
455 This option is needed for the systems that have more than 8 CPUs
456
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800457config X86_EXTENDED_PLATFORM
458 bool "Support for extended (non-PC) x86 platforms"
459 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100460 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100461 If you disable this option then the kernel will only support
462 standard PC platforms. (which covers the vast majority of
463 systems out there.)
464
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800465 If you enable this option then you'll be able to select support
466 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100467 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800468 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800469 RDC R-321x SoC
470 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200471 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200472 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100473
474 If you have one of these systems, or if you want to build a
475 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800476endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100477
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800478if X86_64
479config X86_EXTENDED_PLATFORM
480 bool "Support for extended (non-PC) x86 platforms"
481 default y
482 ---help---
483 If you disable this option then the kernel will only support
484 standard PC platforms. (which covers the vast majority of
485 systems out there.)
486
487 If you enable this option then you'll be able to select support
488 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800489 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800490 ScaleMP vSMP
491 SGI Ultraviolet
492
493 If you have one of these systems, or if you want to build a
494 generic distribution kernel, say Y here - otherwise say N.
495endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800496# This is an alphabetically sorted list of 64 bit extended platforms
497# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800498config X86_NUMACHIP
499 bool "Numascale NumaChip"
500 depends on X86_64
501 depends on X86_EXTENDED_PLATFORM
502 depends on NUMA
503 depends on SMP
504 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700505 depends on PCI_MMCONFIG
Steffen Persvold44b111b52011-12-06 00:07:26 +0800506 ---help---
507 Adds support for Numascale NumaChip large-SMP systems. Needed to
508 enable more than ~168 cores.
509 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100510
Ingo Molnar6a485652009-01-27 18:29:13 +0100511config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800512 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100513 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100514 select PARAVIRT
515 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800516 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300517 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100518 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100519 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
520 supposed to run on these EM64T-based machines. Only choose this option
521 if you have one of these machines.
522
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800523config X86_UV
524 bool "SGI Ultraviolet"
525 depends on X86_64
526 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500527 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800528 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700529 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200530 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800531 ---help---
532 This option is needed in order to support SGI Ultraviolet systems.
533 If you don't have one of these, you should say N here.
534
535# Following is an alphabetically sorted list of 32 bit extended platforms
536# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100537
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000538config X86_GOLDFISH
539 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100540 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000541 ---help---
542 Enable support for the Goldfish virtual platform used primarily
543 for Android development. Unless you are building for the Android
544 Goldfish emulator say N here.
545
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800546config X86_INTEL_CE
547 bool "CE4100 TV platform"
548 depends on PCI
549 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800550 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800551 depends on X86_32
552 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800553 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100554 select OF
555 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800556 ---help---
557 Select for the Intel CE media processor (CE4100) SOC.
558 This option compiles in support for the CE4100 SOC for settop
559 boxes and media devices.
560
David Cohen4cb9b002013-12-16 17:37:26 -0800561config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100562 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100563 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800564 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000565 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200566 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000567 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000568 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800569 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000570 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000571 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000572 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000573 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000574 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800575 Select to build a kernel capable of supporting Intel MID (Mobile
576 Internet Device) platform systems which do not have the PCI legacy
577 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000578
David Cohen4cb9b002013-12-16 17:37:26 -0800579 Intel MID platforms are based on an Intel processor and chipset which
580 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100581
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000582config X86_INTEL_QUARK
583 bool "Intel Quark platform support"
584 depends on X86_32
585 depends on X86_EXTENDED_PLATFORM
586 depends on X86_PLATFORM_DEVICES
587 depends on X86_TSC
588 depends on PCI
589 depends on PCI_GOANY
590 depends on X86_IO_APIC
591 select IOSF_MBI
592 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200593 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000594 ---help---
595 Select to include support for Quark X1000 SoC.
596 Say Y here if you have a Quark based system such as the Arduino
597 compatible Intel Galileo.
598
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000599config X86_INTEL_LPSS
600 bool "Intel Low Power Subsystem Support"
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100601 depends on X86 && ACPI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000602 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300603 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100604 select IOSF_MBI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000605 ---help---
606 Select to build support for Intel Low Power Subsystem such as
607 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300608 things like clock tree (common clock framework) and pincontrol
609 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000610
Ken Xue92082a82015-02-06 08:27:51 +0800611config X86_AMD_PLATFORM_DEVICE
612 bool "AMD ACPI2Platform devices support"
613 depends on ACPI
614 select COMMON_CLK
615 select PINCTRL
616 ---help---
617 Select to interpret AMD specific ACPI device to platform device
618 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
619 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
620 implemented under PINCTRL subsystem.
621
David E. Boxced3ce72014-09-17 22:13:50 -0700622config IOSF_MBI
623 tristate "Intel SoC IOSF Sideband support for SoC platforms"
624 depends on PCI
625 ---help---
626 This option enables sideband register access support for Intel SoC
627 platforms. On these platforms the IOSF sideband is used in lieu of
628 MSR's for some register accesses, mostly but not limited to thermal
629 and power. Drivers may query the availability of this device to
630 determine if they need the sideband in order to work on these
631 platforms. The sideband is available on the following SoC products.
632 This list is not meant to be exclusive.
633 - BayTrail
634 - Braswell
635 - Quark
636
637 You should say Y if you are running a kernel on one of these SoC's.
638
David E. Boxed2226b2014-09-17 22:13:51 -0700639config IOSF_MBI_DEBUG
640 bool "Enable IOSF sideband access through debugfs"
641 depends on IOSF_MBI && DEBUG_FS
642 ---help---
643 Select this option to expose the IOSF sideband access registers (MCR,
644 MDR, MCRX) through debugfs to write and read register information from
645 different units on the SoC. This is most useful for obtaining device
646 state information for debug and analysis. As this is a general access
647 mechanism, users of this option would have specific knowledge of the
648 device they want to access.
649
650 If you don't require the option or are in doubt, say N.
651
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800652config X86_RDC321X
653 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100654 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800655 depends on X86_EXTENDED_PLATFORM
656 select M486
657 select X86_REBOOTFIXUPS
658 ---help---
659 This option is needed for RDC R-321x system-on-chip, also known
660 as R-8610-(G).
661 If you don't have one of these chips, you should say N here.
662
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100663config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100664 bool "Support non-standard 32-bit SMP architectures"
665 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800666 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100667 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800668 This option compiles in the bigsmp and STA2X11 default
669 subarchitectures. It is intended for a generic binary
670 kernel. If you select them all, kernel will probe it one by
671 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700672
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800673# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700674
Linus Torvaldsd949f362009-09-26 09:35:07 -0700675config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100676 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700677 # MCE code calls memory_failure():
678 depends on X86_MCE
679 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700680 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
681 depends on X86_64 || !SPARSEMEM
682 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700683
Alessandro Rubini83125a32012-04-04 19:40:21 +0200684config STA2X11
685 bool "STA2X11 Companion Chip Support"
686 depends on X86_32_NON_STANDARD && PCI
Christoph Hellwigb6e05472018-03-19 11:38:24 +0100687 select ARCH_HAS_PHYS_TO_DMA
Alessandro Rubini83125a32012-04-04 19:40:21 +0200688 select X86_DEV_DMA_OPS
689 select X86_DMA_REMAP
690 select SWIOTLB
691 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200692 select GPIOLIB
Alessandro Rubini83125a32012-04-04 19:40:21 +0200693 default n
694 ---help---
695 This adds support for boards based on the STA2X11 IO-Hub,
696 a.k.a. "ConneXt". The chip is used in place of the standard
697 PC chipset, so all "standard" peripherals are missing. If this
698 option is selected the kernel will still be able to boot on
699 standard PC machines.
700
Shérab82148d12010-09-25 06:06:57 +0200701config X86_32_IRIS
702 tristate "Eurobraille/Iris poweroff module"
703 depends on X86_32
704 ---help---
705 The Iris machines from EuroBraille do not have APM or ACPI support
706 to shut themselves down properly. A special I/O sequence is
707 needed to do so, which is what this module does at
708 kernel shutdown.
709
710 This is only for Iris machines from EuroBraille.
711
712 If unused, say N.
713
Ingo Molnarae1e9132008-11-11 09:05:16 +0100714config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100715 def_bool y
716 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800717 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100718 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100719 Calculate simpler /proc/<PID>/wchan values. If this option
720 is disabled then wchan values will recurse back to the
721 caller function. This provides more accurate wchan values,
722 at the expense of slightly more scheduling overhead.
723
724 If in doubt, say "Y".
725
Borislav Petkov6276a072013-03-04 21:20:21 +0100726menuconfig HYPERVISOR_GUEST
727 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100728 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100729 Say Y here to enable options for running Linux under various hyper-
730 visors. This option enables basic hypervisor detection and platform
731 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100732
Borislav Petkov6276a072013-03-04 21:20:21 +0100733 If you say N, all options in this submenu will be skipped and
734 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100735
Borislav Petkov6276a072013-03-04 21:20:21 +0100736if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100737
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100738config PARAVIRT
739 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100740 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100741 This changes the kernel so it can modify itself when it is run
742 under a hypervisor, potentially improving performance significantly
743 over full virtualization. However, when run without a hypervisor
744 the kernel is theoretically slower and slightly larger.
745
Borislav Petkov6276a072013-03-04 21:20:21 +0100746config PARAVIRT_DEBUG
747 bool "paravirt-ops debugging"
748 depends on PARAVIRT && DEBUG_KERNEL
749 ---help---
750 Enable to debug paravirt_ops internals. Specifically, BUG if
751 a paravirt_op is missing when it is called.
752
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700753config PARAVIRT_SPINLOCKS
754 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700755 depends on PARAVIRT && SMP
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700756 ---help---
757 Paravirtualized spinlocks allow a pvops backend to replace the
758 spinlock implementation with something virtualization-friendly
759 (for example, block the virtual CPU rather than spinning).
760
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530761 It has a minimal impact on native kernels and gives a nice performance
762 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700763
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530764 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700765
Waiman Long45e898b2015-11-09 19:09:25 -0500766config QUEUED_LOCK_STAT
767 bool "Paravirt queued spinlock statistics"
Peter Zijlstracfd89832016-05-18 20:43:02 +0200768 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
Waiman Long45e898b2015-11-09 19:09:25 -0500769 ---help---
770 Enable the collection of statistical data on the slowpath
771 behavior of paravirtualized queued spinlocks and report
772 them on debugfs.
773
Borislav Petkov6276a072013-03-04 21:20:21 +0100774source "arch/x86/xen/Kconfig"
775
776config KVM_GUEST
777 bool "KVM Guest support (including kvmclock)"
778 depends on PARAVIRT
779 select PARAVIRT_CLOCK
780 default y
781 ---help---
782 This option enables various optimizations for running under the KVM
783 hypervisor. It includes a paravirtualized clock, so that instead
784 of relying on a PIT (or probably other) emulation by the
785 underlying device model, the host provides the guest with
786 timing infrastructure such as time of day, and system time
787
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530788config KVM_DEBUG_FS
789 bool "Enable debug information for KVM Guests in debugfs"
790 depends on KVM_GUEST && DEBUG_FS
791 default n
792 ---help---
793 This option enables collection of various statistics for KVM guest.
794 Statistics are displayed in debugfs filesystem. Enabling this option
795 may incur significant overhead.
796
Borislav Petkov6276a072013-03-04 21:20:21 +0100797config PARAVIRT_TIME_ACCOUNTING
798 bool "Paravirtual steal time accounting"
799 depends on PARAVIRT
800 default n
801 ---help---
802 Select this option to enable fine granularity task steal time
803 accounting. Time spent executing other tasks in parallel with
804 the current vCPU is discounted from the vCPU power. To account for
805 that, there can be a small performance impact.
806
807 If in doubt, say N here.
808
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200809config PARAVIRT_CLOCK
810 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200811
Jan Kiszka4a362602017-11-27 09:11:46 +0100812config JAILHOUSE_GUEST
813 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100814 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100815 select X86_PM_TIMER
Jan Kiszka4a362602017-11-27 09:11:46 +0100816 ---help---
817 This option allows to run Linux as guest in a Jailhouse non-root
818 cell. You can leave this option disabled if you only want to start
819 Jailhouse and run Linux afterwards in the root cell.
820
Borislav Petkov6276a072013-03-04 21:20:21 +0100821endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400822
Yinghai Lu08677212010-02-10 01:20:20 -0800823config NO_BOOTMEM
Yinghai Lu774ea0b2010-08-25 13:39:18 -0700824 def_bool y
Yinghai Lu08677212010-02-10 01:20:20 -0800825
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100826source "arch/x86/Kconfig.cpu"
827
828config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100829 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100830 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100831 ---help---
832 Use the IA-PC HPET (High Precision Event Timer) to manage
833 time in preference to the PIT and RTC, if a HPET is
834 present.
835 HPET is the next generation timer replacing legacy 8254s.
836 The HPET provides a stable time base on SMP
837 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200838 as it is off-chip. The interface used is documented
839 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100840
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100841 You can safely choose Y here. However, HPET will only be
842 activated if the platform and the BIOS support this feature.
843 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100844
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100845 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100846
847config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100848 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800849 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100850
Jacob Panbb24c472009-09-02 07:37:17 -0700851config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000852 def_bool y if X86_INTEL_MID
853 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100854 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000855 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700856 help
857 APB timer is the replacement for 8254, HPET on X86 MID platforms.
858 The APBT provides a stable time base on SMP
859 systems, unlike the TSC, but it is more expensive to access,
860 as it is off-chip. APB timers are always running regardless of CPU
861 C states, they are used as per CPU clockevent device when possible.
862
David Rientjes6a108a12011-01-20 14:44:16 -0800863# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100864# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700865config DMI
866 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800867 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800868 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100869 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700870 Enabled scanning of DMI to identify machine quirks. Say Y
871 here unless you have verified that your setup is not
872 affected by entries in the DMI blacklist. Required by PNP
873 BIOS code.
874
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100875config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700876 bool "Old AMD GART IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200877 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100878 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200879 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100880 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200881 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
882 GART based hardware IOMMUs.
883
884 The GART supports full DMA access for devices with 32-bit access
885 limitations, on systems with more than 3 GB. This is usually needed
886 for USB, sound, many IDE/SATA chipsets and some other devices.
887
888 Newer systems typically have a modern AMD IOMMU, supported via
889 the CONFIG_AMD_IOMMU=y config option.
890
891 In normal configurations this driver is only active when needed:
892 there's more than 3 GB of memory and the system contains a
893 32-bit limited device.
894
895 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100896
897config CALGARY_IOMMU
898 bool "IBM Calgary IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200899 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100900 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700901 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100902 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100903 Support for hardware IOMMUs in IBM's xSeries x366 and x460
904 systems. Needed to run systems with more than 3GB of memory
905 properly with 32-bit PCI devices that do not support DAC
906 (Double Address Cycle). Calgary also supports bus level
907 isolation, where all DMAs pass through the IOMMU. This
908 prevents them from going anywhere except their intended
909 destination. This catches hard-to-find kernel bugs and
910 mis-behaving drivers and devices that do not use the DMA-API
911 properly to set up their DMA buffers. The IOMMU can be
912 turned off at boot time with the iommu=off parameter.
913 Normally the kernel will make the right choice by itself.
914 If unsure, say Y.
915
916config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100917 def_bool y
918 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100919 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100920 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100921 Should Calgary be enabled by default? if you choose 'y', Calgary
922 will be used (if it exists). If you choose 'n', Calgary will not be
923 used even if it exists. If you choose 'n' and would like to use
924 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
925 If unsure, say Y.
926
927# need this always selected by IOMMU for the VIA workaround
928config SWIOTLB
Joerg Roedela1afd012008-11-18 12:44:21 +0100929 def_bool y if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100930 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100931 Support for software bounce buffers used on x86-64 systems
Joe Millenbach4454d322012-09-02 17:38:20 -0700932 which don't have a hardware IOMMU. Using this PCI devices
933 which can only access 32-bits of memory can be used on systems
934 with more than 3 GB of memory.
935 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100936
Mike Travis1184dc22008-05-12 21:21:12 +0200937config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200938 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700939 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800940 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100941 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200942 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200943 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100944
Ingo Molnaraec64872018-02-10 12:36:29 +0100945#
946# The maximum number of CPUs supported:
947#
948# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
949# and which can be configured interactively in the
950# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
951#
952# The ranges are different on 32-bit and 64-bit kernels, depending on
953# hardware capabilities and scalability features of the kernel.
954#
955# ( If MAXSMP is enabled we just use the highest possible value and disable
956# interactive configuration. )
957#
958
959config NR_CPUS_RANGE_BEGIN
960 int
961 default NR_CPUS_RANGE_END if MAXSMP
962 default 1 if !SMP
963 default 2
964
965config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800966 int
967 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100968 default 64 if SMP && X86_BIGSMP
969 default 8 if SMP && !X86_BIGSMP
970 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800971
Ingo Molnaraec64872018-02-10 12:36:29 +0100972config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800973 int
974 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100975 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
976 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
977 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800978
Ingo Molnaraec64872018-02-10 12:36:29 +0100979config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800980 int
981 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100982 default 32 if X86_BIGSMP
983 default 8 if SMP
984 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800985
Ingo Molnaraec64872018-02-10 12:36:29 +0100986config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800987 int
988 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100989 default 8192 if MAXSMP
990 default 64 if SMP
991 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800992
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100993config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800994 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +0100995 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
996 default NR_CPUS_DEFAULT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100997 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100998 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500999 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +03001000 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001001 minimum value which makes sense is 2.
1002
Ingo Molnaraec64872018-02-10 12:36:29 +01001003 This is purely to save memory: each supported CPU adds about 8KB
1004 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001005
1006config SCHED_SMT
1007 bool "SMT (Hyperthreading) scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001008 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001009 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001010 SMT scheduler support improves the CPU scheduler's decision making
1011 when dealing with Intel Pentium 4 chips with HyperThreading at a
1012 cost of slightly increased overhead in some places. If unsure say
1013 N here.
1014
1015config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001016 def_bool y
1017 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001018 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001019 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001020 Multi-core scheduler support improves the CPU scheduler's decision
1021 making when dealing with multi-core CPU chips at a cost of slightly
1022 increased overhead in some places. If unsure say N here.
1023
Tim Chende966cf2016-11-29 10:43:27 -08001024config SCHED_MC_PRIO
1025 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001026 depends on SCHED_MC && CPU_SUP_INTEL
1027 select X86_INTEL_PSTATE
1028 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001029 default y
Tim Chen5e76b2a2016-11-22 12:23:55 -08001030 ---help---
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001031 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1032 core ordering determined at manufacturing time, which allows
1033 certain cores to reach higher turbo frequencies (when running
1034 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001035
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001036 Enabling this kernel feature teaches the scheduler about
1037 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1038 scheduler's CPU selection logic accordingly, so that higher
1039 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001040
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001041 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001042
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001043 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001044
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001045source "kernel/Kconfig.preempt"
1046
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001047config UP_LATE_INIT
1048 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +01001049 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001050
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001051config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001052 bool "Local APIC support on uniprocessors" if !PCI_MSI
1053 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001054 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001055 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001056 A local APIC (Advanced Programmable Interrupt Controller) is an
1057 integrated interrupt controller in the CPU. If you have a single-CPU
1058 system which has a processor with a local APIC, you can say Y here to
1059 enable and use it. If you say Y here even though your machine doesn't
1060 have a local APIC, then the kernel will still run with no slowdown at
1061 all. The local APIC supports CPU-generated self-interrupts (timer,
1062 performance counters), and the NMI watchdog which detects hard
1063 lockups.
1064
1065config X86_UP_IOAPIC
1066 bool "IO-APIC support on uniprocessors"
1067 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001068 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001069 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1070 SMP-capable replacement for PC-style interrupt controllers. Most
1071 SMP systems and many recent uniprocessor systems have one.
1072
1073 If you have a single-CPU system with an IO-APIC, you can say Y here
1074 to use it. If you say Y here even though your machine doesn't have
1075 an IO-APIC, then the kernel will still run with no slowdown at all.
1076
1077config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001078 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001079 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001080 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001081 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001082
1083config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001084 def_bool y
1085 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001086
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001087config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1088 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001089 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001090 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001091 This option enables a workaround that fixes a source of
1092 spurious interrupts. This is recommended when threaded
1093 interrupt handling is used on systems where the generation of
1094 superfluous "boot interrupts" cannot be disabled.
1095
1096 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1097 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1098 kernel does during interrupt handling). On chipsets where this
1099 boot IRQ generation cannot be disabled, this workaround keeps
1100 the original IRQ line masked so that only the equivalent "boot
1101 IRQ" is delivered to the CPUs. The workaround also tells the
1102 kernel to set up the IRQ handler on the boot IRQ line. In this
1103 way only one interrupt is delivered to the kernel. Otherwise
1104 the spurious second interrupt may cause the kernel to bring
1105 down (vital) interrupt lines.
1106
1107 Only affects "broken" chipsets. Interrupt sharing may be
1108 increased on these systems.
1109
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001110config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001111 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001112 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001113 default y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001114 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +02001115 Machine Check support allows the processor to notify the
1116 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001117 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001118 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001119
Tony Luck5de97c92017-03-27 11:33:03 +02001120config X86_MCELOG_LEGACY
1121 bool "Support for deprecated /dev/mcelog character device"
1122 depends on X86_MCE
1123 ---help---
1124 Enable support for /dev/mcelog which is needed by the old mcelog
1125 userspace logging daemon. Consider switching to the new generation
1126 rasdaemon solution.
1127
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001128config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001129 def_bool y
1130 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001131 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001132 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001133 Additional support for intel specific MCE features such as
1134 the thermal monitor.
1135
1136config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001137 def_bool y
1138 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001139 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001140 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001141 Additional support for AMD specific MCE features such as
1142 the DRAM Error Threshold.
1143
Andi Kleen4efc0672009-04-28 19:07:31 +02001144config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001145 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001146 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001147 ---help---
1148 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001149 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001150 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001151
Andi Kleenb2762682009-02-12 13:49:31 +01001152config X86_MCE_THRESHOLD
1153 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001154 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001155
Andi Kleenea149b32009-04-29 19:31:00 +02001156config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001157 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001158 tristate "Machine check injector support"
1159 ---help---
1160 Provide support for injecting machine checks for testing purposes.
1161 If you don't know what a machine check is and you don't do kernel
1162 QA it is safe to say n.
1163
Andi Kleen4efc0672009-04-28 19:07:31 +02001164config X86_THERMAL_VECTOR
1165 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001166 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001167
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001168source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001169
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001170config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001171 bool "Legacy VM86 support"
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001172 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001173 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001174 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001175 This option allows user programs to put the CPU into V8086
1176 mode, which is an 80286-era approximation of 16-bit real mode.
1177
1178 Some very old versions of X and/or vbetool require this option
1179 for user mode setting. Similarly, DOSEMU will use it if
1180 available to accelerate real mode DOS programs. However, any
1181 recent version of DOSEMU, X, or vbetool should be fully
1182 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001183 fall back to software emulation. Nevertheless, if you are using
1184 a 16-bit DOS program where 16-bit performance matters, vm86
1185 mode might be faster than emulation and you might want to
1186 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001187
Ingo Molnar1e642812015-09-05 08:58:10 +02001188 Note that any app that works on a 64-bit kernel is unlikely to
1189 need this option, as 64-bit kernels don't, and can't, support
1190 V8086 mode. This option is also unrelated to 16-bit protected
1191 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001192
Ingo Molnar1e642812015-09-05 08:58:10 +02001193 Enabling this option increases the complexity of the kernel
1194 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001195
Ingo Molnar1e642812015-09-05 08:58:10 +02001196 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001197
1198config VM86
1199 bool
1200 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001201
1202config X86_16BIT
1203 bool "Enable support for 16-bit segments" if EXPERT
1204 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001205 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001206 ---help---
1207 This option is required by programs like Wine to run 16-bit
1208 protected mode legacy code on x86 processors. Disabling
1209 this option saves about 300 bytes on i386, or around 6K text
1210 plus 16K runtime memory on x86-64,
1211
1212config X86_ESPFIX32
1213 def_bool y
1214 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001215
H. Peter Anvin197725d2014-05-04 10:00:49 -07001216config X86_ESPFIX64
1217 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001218 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001219
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001220config X86_VSYSCALL_EMULATION
1221 bool "Enable vsyscall emulation" if EXPERT
1222 default y
1223 depends on X86_64
1224 ---help---
1225 This enables emulation of the legacy vsyscall page. Disabling
1226 it is roughly equivalent to booting with vsyscall=none, except
1227 that it will also disable the helpful warning if a program
1228 tries to use a vsyscall. With this option set to N, offending
1229 programs will just segfault, citing addresses of the form
1230 0xffffffffff600?00.
1231
1232 This option is required by many programs built before 2013, and
1233 care should be used even with newer programs if set to N.
1234
1235 Disabling this option saves about 7K of kernel size and
1236 possibly 4K of additional runtime pagetable memory.
1237
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001238config TOSHIBA
1239 tristate "Toshiba Laptop support"
1240 depends on X86_32
1241 ---help---
1242 This adds a driver to safely access the System Management Mode of
1243 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1244 not work on models with a Phoenix BIOS. The System Management Mode
1245 is used to set the BIOS and power saving options on Toshiba portables.
1246
1247 For information on utilities to make use of this driver see the
1248 Toshiba Linux utilities web site at:
1249 <http://www.buzzard.org.uk/toshiba/>.
1250
1251 Say Y if you intend to run this kernel on a Toshiba portable.
1252 Say N otherwise.
1253
1254config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001255 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001256 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001257 select SENSORS_DELL_SMM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001258 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001259 This option enables legacy /proc/i8k userspace interface in hwmon
1260 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1261 temperature and allows controlling fan speeds of Dell laptops via
1262 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1263 it reports also power and hotkey status. For fan speed control is
1264 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001265
Pali Rohár039ae582015-05-14 13:16:37 +02001266 Say Y if you intend to run this kernel on old Dell laptops or want to
1267 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001268 Say N otherwise.
1269
1270config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001271 bool "Enable X86 board specific fixups for reboot"
1272 depends on X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001273 ---help---
1274 This enables chipset and/or board specific fixups to be done
1275 in order to get reboot to work correctly. This is only needed on
1276 some combinations of hardware and BIOS. The symptom, for which
1277 this config is intended, is when reboot ends with a stalled/hung
1278 system.
1279
1280 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001281 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001282
1283 Say Y if you want to enable the fixup. Currently, it's safe to
1284 enable this option even if you don't need it.
1285 Say N otherwise.
1286
1287config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001288 bool "CPU microcode loading support"
1289 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001290 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001291 select FW_LOADER
1292 ---help---
1293 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001294 Intel and AMD processors. The Intel support is for the IA32 family,
1295 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1296 AMD support is for families 0x10 and later. You will obviously need
1297 the actual microcode binary data itself which is not shipped with
1298 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001299
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001300 The preferred method to load microcode from a detached initrd is described
Jaak Ristioja1897a962018-02-09 11:22:16 +02001301 in Documentation/x86/microcode.txt. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001302 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1303 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001304
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001305 In addition, you can build the microcode into the kernel. For that you
1306 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1307 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001308
Peter Oruba8d86f392008-07-28 18:44:21 +02001309config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001310 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001311 depends on MICROCODE
1312 default MICROCODE
1313 select FW_LOADER
1314 ---help---
1315 This options enables microcode patch loading support for Intel
1316 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001317
Alanb8989db2014-01-20 18:01:56 +00001318 For the current Intel microcode data package go to
1319 <https://downloadcenter.intel.com> and search for
1320 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001321
Peter Oruba80cc9f12008-07-28 18:44:22 +02001322config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001323 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001324 depends on MICROCODE
1325 select FW_LOADER
1326 ---help---
1327 If you select this option, microcode patch loading support for AMD
1328 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001329
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001330config MICROCODE_OLD_INTERFACE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001331 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001332 depends on MICROCODE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001333
1334config X86_MSR
1335 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001336 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001337 This device gives privileged processes access to the x86
1338 Model-Specific Registers (MSRs). It is a character device with
1339 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1340 MSR accesses are directed to a specific CPU on multi-processor
1341 systems.
1342
1343config X86_CPUID
1344 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001345 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001346 This device gives processes access to the x86 CPUID instruction to
1347 be executed on a specific processor. It is a character device
1348 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1349 /dev/cpu/31/cpuid.
1350
1351choice
1352 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001353 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001354 depends on X86_32
1355
1356config NOHIGHMEM
1357 bool "off"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001358 ---help---
1359 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1360 However, the address space of 32-bit x86 processors is only 4
1361 Gigabytes large. That means that, if you have a large amount of
1362 physical memory, not all of it can be "permanently mapped" by the
1363 kernel. The physical memory that's not permanently mapped is called
1364 "high memory".
1365
1366 If you are compiling a kernel which will never run on a machine with
1367 more than 1 Gigabyte total physical RAM, answer "off" here (default
1368 choice and suitable for most users). This will result in a "3GB/1GB"
1369 split: 3GB are mapped so that each process sees a 3GB virtual memory
1370 space and the remaining part of the 4GB virtual memory space is used
1371 by the kernel to permanently map as much physical memory as
1372 possible.
1373
1374 If the machine has between 1 and 4 Gigabytes physical RAM, then
1375 answer "4GB" here.
1376
1377 If more than 4 Gigabytes is used then answer "64GB" here. This
1378 selection turns Intel PAE (Physical Address Extension) mode on.
1379 PAE implements 3-level paging on IA32 processors. PAE is fully
1380 supported by Linux, PAE mode is implemented on all recent Intel
1381 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1382 then the kernel will not boot on CPUs that don't support PAE!
1383
1384 The actual amount of total physical memory will either be
1385 auto detected or can be forced by using a kernel command line option
1386 such as "mem=256M". (Try "man bootparam" or see the documentation of
1387 your boot loader (lilo or loadlin) about how to pass options to the
1388 kernel at boot time.)
1389
1390 If unsure, say "off".
1391
1392config HIGHMEM4G
1393 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001394 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001395 Select this if you have a 32-bit processor and between 1 and 4
1396 gigabytes of physical RAM.
1397
1398config HIGHMEM64G
1399 bool "64GB"
Matthew Whitehead69b8d3f2018-02-15 11:54:55 -05001400 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001401 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001402 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001403 Select this if you have a 32-bit processor and more than 4
1404 gigabytes of physical RAM.
1405
1406endchoice
1407
1408choice
David Rientjes6a108a12011-01-20 14:44:16 -08001409 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001410 default VMSPLIT_3G
1411 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001412 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001413 Select the desired split between kernel and user memory.
1414
1415 If the address range available to the kernel is less than the
1416 physical memory installed, the remaining memory will be available
1417 as "high memory". Accessing high memory is a little more costly
1418 than low memory, as it needs to be mapped into the kernel first.
1419 Note that increasing the kernel address space limits the range
1420 available to user programs, making the address space there
1421 tighter. Selecting anything other than the default 3G/1G split
1422 will also likely make your kernel incompatible with binary-only
1423 kernel modules.
1424
1425 If you are not absolutely sure what you are doing, leave this
1426 option alone!
1427
1428 config VMSPLIT_3G
1429 bool "3G/1G user/kernel split"
1430 config VMSPLIT_3G_OPT
1431 depends on !X86_PAE
1432 bool "3G/1G user/kernel split (for full 1G low memory)"
1433 config VMSPLIT_2G
1434 bool "2G/2G user/kernel split"
1435 config VMSPLIT_2G_OPT
1436 depends on !X86_PAE
1437 bool "2G/2G user/kernel split (for full 2G low memory)"
1438 config VMSPLIT_1G
1439 bool "1G/3G user/kernel split"
1440endchoice
1441
1442config PAGE_OFFSET
1443 hex
1444 default 0xB0000000 if VMSPLIT_3G_OPT
1445 default 0x80000000 if VMSPLIT_2G
1446 default 0x78000000 if VMSPLIT_2G_OPT
1447 default 0x40000000 if VMSPLIT_1G
1448 default 0xC0000000
1449 depends on X86_32
1450
1451config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001452 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001453 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001454
1455config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001456 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001457 depends on X86_32 && !HIGHMEM4G
Christian Melki9d99c712015-10-05 17:31:33 +02001458 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001459 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001460 PAE is required for NX support, and furthermore enables
1461 larger swapspace support for non-overcommit purposes. It
1462 has the cost of more pagetable lookup overhead, and also
1463 consumes more pagetable space per process.
1464
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001465config X86_5LEVEL
1466 bool "Enable 5-level page tables support"
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001467 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001468 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001469 depends on X86_64
1470 ---help---
1471 5-level paging enables access to larger address space:
1472 upto 128 PiB of virtual address space and 4 PiB of
1473 physical address space.
1474
1475 It will be supported by future Intel CPUs.
1476
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001477 A kernel with the option enabled can be booted on machines that
1478 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001479
1480 See Documentation/x86/x86_64/5level-paging.txt for more
1481 information.
1482
1483 Say N if unsure.
1484
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001485config ARCH_PHYS_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001486 def_bool y
1487 depends on X86_64 || X86_PAE
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001488
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001489config ARCH_DMA_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001490 def_bool y
1491 depends on X86_64 || HIGHMEM64G
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001492
Ingo Molnar10971ab2015-03-05 08:18:23 +01001493config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001494 def_bool y
Levin, Alexander (Sasha Levin)4675ff02017-11-15 17:36:02 -08001495 depends on X86_64 && !DEBUG_PAGEALLOC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001496 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001497 Certain kernel features effectively disable kernel
1498 linear 1 GB mappings (even if the CPU otherwise
1499 supports them), so don't confuse the user by printing
1500 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001501
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001502config ARCH_HAS_MEM_ENCRYPT
1503 def_bool y
1504
1505config AMD_MEM_ENCRYPT
1506 bool "AMD Secure Memory Encryption (SME) support"
1507 depends on X86_64 && CPU_SUP_AMD
1508 ---help---
1509 Say yes to enable support for the encryption of system memory.
1510 This requires an AMD processor that supports Secure Memory
1511 Encryption (SME).
1512
1513config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1514 bool "Activate AMD Secure Memory Encryption (SME) by default"
1515 default y
1516 depends on AMD_MEM_ENCRYPT
1517 ---help---
1518 Say yes to have system memory encrypted by default if running on
1519 an AMD processor that supports Secure Memory Encryption (SME).
1520
1521 If set to Y, then the encryption of system memory can be
1522 deactivated with the mem_encrypt=off command line option.
1523
1524 If set to N, then the encryption of system memory can be
1525 activated with the mem_encrypt=on command line option.
1526
Tom Lendackyf88a68f2017-07-17 16:10:09 -05001527config ARCH_USE_MEMREMAP_PROT
1528 def_bool y
1529 depends on AMD_MEM_ENCRYPT
1530
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001531# Common NUMA Features
1532config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001533 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001534 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001535 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1536 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001537 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001538 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001539
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001540 The kernel will try to allocate memory used by a CPU on the
1541 local memory controller of the CPU and add some more
1542 NUMA awareness to the kernel.
1543
Ingo Molnarc280ea52008-11-08 13:29:45 +01001544 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001545 (or later), AMD Opteron, or EM64T NUMA.
1546
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001547 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001548 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001549
1550 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001551
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001552config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001553 def_bool y
1554 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001555 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001556 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001557 Enable AMD NUMA node topology detection. You should say Y here if
1558 you have a multi processor AMD system. This uses an old method to
1559 read the NUMA configuration directly from the builtin Northbridge
1560 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1561 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001562
1563config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001564 def_bool y
1565 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001566 depends on X86_64 && NUMA && ACPI && PCI
1567 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001568 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001569 Enable ACPI SRAT based node topology detection.
1570
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001571# Some NUMA nodes have memory ranges that span
1572# other nodes. Even though a pfn is valid and
1573# between a node's start and end pfns, it may not
1574# reside on that node. See memmap_init_zone()
1575# for details.
1576config NODES_SPAN_OTHER_NODES
1577 def_bool y
1578 depends on X86_64_ACPI_NUMA
1579
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001580config NUMA_EMU
1581 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001582 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001583 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001584 Enable NUMA emulation. A flat machine will be split
1585 into virtual nodes when booted with "numa=fake=N", where N is the
1586 number of nodes. This is only useful for debugging.
1587
1588config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001589 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001590 range 1 10
1591 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001592 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001593 default "3"
1594 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001595 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001596 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001597 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001598
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001599config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001600 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001601 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001602
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001603config ARCH_FLATMEM_ENABLE
1604 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001605 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001606
1607config ARCH_DISCONTIGMEM_ENABLE
1608 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001609 depends on NUMA && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001610
1611config ARCH_DISCONTIGMEM_DEFAULT
1612 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001613 depends on NUMA && X86_32
1614
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001615config ARCH_SPARSEMEM_ENABLE
1616 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001617 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001618 select SPARSEMEM_STATIC if X86_32
1619 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1620
Tejun Heo3b166512011-04-01 11:15:12 +02001621config ARCH_SPARSEMEM_DEFAULT
1622 def_bool y
1623 depends on X86_64
1624
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001625config ARCH_SELECT_MEMORY_MODEL
1626 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001627 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001628
1629config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001630 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001631 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001632 help
1633 This option enables a sysfs memory/probe interface for testing.
1634 See Documentation/memory-hotplug.txt for more information.
1635 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001636
Tejun Heo3b166512011-04-01 11:15:12 +02001637config ARCH_PROC_KCORE_TEXT
1638 def_bool y
1639 depends on X86_64 && PROC_KCORE
1640
Avi Kivitya29815a2010-01-10 16:28:09 +02001641config ILLEGAL_POINTER_VALUE
1642 hex
1643 default 0 if X86_32
1644 default 0xdead000000000000 if X86_64
1645
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001646source "mm/Kconfig"
1647
Dan Williams7a678322015-08-19 00:34:34 -04001648config X86_PMEM_LEGACY_DEVICE
1649 bool
1650
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001651config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001652 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001653 depends on PHYS_ADDR_T_64BIT
1654 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001655 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001656 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001657 help
1658 Treat memory marked using the non-standard e820 type of 12 as used
1659 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1660 The kernel will offer these regions to the 'pmem' driver so
1661 they can be used for persistent storage.
1662
1663 Say Y if unsure.
1664
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001665config HIGHPTE
1666 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001667 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001668 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001669 The VM uses one page table entry for each page of physical memory.
1670 For systems with a lot of RAM, this can be wasteful of precious
1671 low memory. Setting this option will put user-space page table
1672 entries in high memory.
1673
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001674config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001675 bool "Check for low memory corruption"
1676 ---help---
1677 Periodically check for memory corruption in low memory, which
1678 is suspected to be caused by BIOS. Even when enabled in the
1679 configuration, it is disabled at runtime. Enable it by
1680 setting "memory_corruption_check=1" on the kernel command
1681 line. By default it scans the low 64k of memory every 60
1682 seconds; see the memory_corruption_check_size and
1683 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001684 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001685
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001686 When enabled with the default parameters, this option has
1687 almost no overhead, as it reserves a relatively small amount
1688 of memory and scans it infrequently. It both detects corruption
1689 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001690
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001691 It is, however, intended as a diagnostic tool; if repeatable
1692 BIOS-originated corruption always affects the same memory,
1693 you can use memmap= to prevent the kernel from using that
1694 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001695
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001696config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001697 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001698 depends on X86_CHECK_BIOS_CORRUPTION
1699 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001700 ---help---
1701 Set whether the default state of memory_corruption_check is
1702 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001703
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001704config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001705 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1706 default 64
1707 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001708 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001709 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001710
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001711 The first page contains BIOS data structures that the kernel
1712 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001713
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001714 By default we reserve the first 64K of physical RAM, as a
1715 number of BIOSes are known to corrupt that memory range
1716 during events such as suspend/resume or monitor cable
1717 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001718
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001719 You can set this to 4 if you are absolutely sure that you
1720 trust the BIOS to get all its memory reservations and usages
1721 right. If you know your BIOS have problems beyond the
1722 default 64K area, you can set this to 640 to avoid using the
1723 entire low memory range.
1724
1725 If you have doubts about the BIOS (e.g. suspend/resume does
1726 not work or there's kernel crashes after certain hardware
1727 hotplug events) then you might want to enable
1728 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1729 typical corruption patterns.
1730
1731 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001732
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001733config MATH_EMULATION
1734 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001735 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001736 prompt "Math emulation" if X86_32
1737 ---help---
1738 Linux can emulate a math coprocessor (used for floating point
1739 operations) if you don't have one. 486DX and Pentium processors have
1740 a math coprocessor built in, 486SX and 386 do not, unless you added
1741 a 487DX or 387, respectively. (The messages during boot time can
1742 give you some hints here ["man dmesg"].) Everyone needs either a
1743 coprocessor or this emulation.
1744
1745 If you don't have a math coprocessor, you need to say Y here; if you
1746 say Y here even though you have a coprocessor, the coprocessor will
1747 be used nevertheless. (This behavior can be changed with the kernel
1748 command line option "no387", which comes handy if your coprocessor
1749 is broken. Try "man bootparam" or see the documentation of your boot
1750 loader (lilo or loadlin) about how to pass options to the kernel at
1751 boot time.) This means that it is a good idea to say Y here if you
1752 intend to use this kernel on different machines.
1753
1754 More information about the internals of the Linux math coprocessor
1755 emulation can be found in <file:arch/x86/math-emu/README>.
1756
1757 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1758 kernel, it won't hurt.
1759
1760config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001761 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001762 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001763 ---help---
1764 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1765 the Memory Type Range Registers (MTRRs) may be used to control
1766 processor access to memory ranges. This is most useful if you have
1767 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1768 allows bus write transfers to be combined into a larger transfer
1769 before bursting over the PCI/AGP bus. This can increase performance
1770 of image write operations 2.5 times or more. Saying Y here creates a
1771 /proc/mtrr file which may be used to manipulate your processor's
1772 MTRRs. Typically the X server should use this.
1773
1774 This code has a reasonably generic interface so that similar
1775 control registers on other processors can be easily supported
1776 as well:
1777
1778 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1779 Registers (ARRs) which provide a similar functionality to MTRRs. For
1780 these, the ARRs are used to emulate the MTRRs.
1781 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1782 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1783 write-combining. All of these processors are supported by this code
1784 and it makes sense to say Y here if you have one of them.
1785
1786 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1787 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1788 can lead to all sorts of problems, so it's good to say Y here.
1789
1790 You can safely say Y even if your machine doesn't have MTRRs, you'll
1791 just add about 9 KB to your kernel.
1792
Randy Dunlap7225e752008-07-26 17:54:22 -07001793 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001794
Yinghai Lu95ffa242008-04-29 03:52:33 -07001795config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001796 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001797 prompt "MTRR cleanup support"
1798 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001799 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001800 Convert MTRR layout from continuous to discrete, so X drivers can
1801 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001802
Thomas Gleixneraba37282008-07-15 14:48:48 +02001803 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001804 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001805 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001806
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001807 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001808
1809config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001810 int "MTRR cleanup enable value (0-1)"
1811 range 0 1
1812 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001813 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001814 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001815 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001816
Yinghai Lu12031a62008-05-02 02:40:22 -07001817config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1818 int "MTRR cleanup spare reg num (0-7)"
1819 range 0 7
1820 default "1"
1821 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001822 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001823 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001824 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001825
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001826config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001827 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001828 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001829 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001830 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001831 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001832
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001833 PATs are the modern equivalents of MTRRs and are much more
1834 flexible than MTRRs.
1835
1836 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001837 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001838
1839 If unsure, say Y.
1840
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001841config ARCH_USES_PG_UNCACHED
1842 def_bool y
1843 depends on X86_PAT
1844
H. Peter Anvin628c6242011-07-31 13:59:29 -07001845config ARCH_RANDOM
1846 def_bool y
1847 prompt "x86 architectural random number generator" if EXPERT
1848 ---help---
1849 Enable the x86 architectural RDRAND instruction
1850 (Intel Bull Mountain technology) to generate random numbers.
1851 If supported, this is a high bandwidth, cryptographically
1852 secure hardware random number generator.
1853
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001854config X86_SMAP
1855 def_bool y
1856 prompt "Supervisor Mode Access Prevention" if EXPERT
1857 ---help---
1858 Supervisor Mode Access Prevention (SMAP) is a security
1859 feature in newer Intel processors. There is a small
1860 performance cost if this enabled and turned on; there is
1861 also a small increase in the kernel size if this is enabled.
1862
1863 If unsure, say Y.
1864
Ricardo Neriaa35f892017-11-05 18:27:54 -08001865config X86_INTEL_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001866 def_bool y
Ricardo Neriaa35f892017-11-05 18:27:54 -08001867 depends on CPU_SUP_INTEL
1868 prompt "Intel User Mode Instruction Prevention" if EXPERT
1869 ---help---
1870 The User Mode Instruction Prevention (UMIP) is a security
1871 feature in newer Intel processors. If enabled, a general
Ricardo Neri796ebc82017-11-13 22:29:42 -08001872 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1873 or STR instructions are executed in user mode. These instructions
1874 unnecessarily expose information about the hardware state.
1875
1876 The vast majority of applications do not use these instructions.
1877 For the very few that do, software emulation is provided in
1878 specific cases in protected and virtual-8086 modes. Emulated
1879 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001880
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001881config X86_INTEL_MPX
1882 prompt "Intel MPX (Memory Protection Extensions)"
1883 def_bool n
Rik van Rieldf3735c2017-09-06 16:25:11 -07001884 # Note: only available in 64-bit mode due to VMA flags shortage
1885 depends on CPU_SUP_INTEL && X86_64
1886 select ARCH_USES_HIGH_VMA_FLAGS
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001887 ---help---
1888 MPX provides hardware features that can be used in
1889 conjunction with compiler-instrumented code to check
1890 memory references. It is designed to detect buffer
1891 overflow or underflow bugs.
1892
1893 This option enables running applications which are
1894 instrumented or otherwise use MPX. It does not use MPX
1895 itself inside the kernel or to protect the kernel
1896 against bad memory references.
1897
1898 Enabling this option will make the kernel larger:
1899 ~8k of kernel text and 36 bytes of data on a 64-bit
1900 defconfig. It adds a long to the 'mm_struct' which
1901 will increase the kernel memory overhead of each
1902 process and adds some branches to paths used during
1903 exec() and munmap().
1904
1905 For details, see Documentation/x86/intel_mpx.txt
1906
1907 If unsure, say N.
1908
Dave Hansen35e97792016-02-12 13:02:00 -08001909config X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001910 prompt "Intel Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001911 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001912 # Note: only available in 64-bit mode
Dave Hansen35e97792016-02-12 13:02:00 -08001913 depends on CPU_SUP_INTEL && X86_64
Ingo Molnar52c8e602016-11-15 10:15:03 +01001914 select ARCH_USES_HIGH_VMA_FLAGS
1915 select ARCH_HAS_PKEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001916 ---help---
1917 Memory Protection Keys provides a mechanism for enforcing
1918 page-based protections, but without requiring modification of the
1919 page tables when an application changes protection domains.
1920
1921 For details, see Documentation/x86/protection-keys.txt
1922
1923 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001924
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001925config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001926 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001927 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001928 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001929 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001930 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001931 This enables the kernel to use EFI runtime services that are
1932 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001933
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001934 This option is only useful on systems that have EFI firmware.
1935 In addition, you should use the latest ELILO loader available
1936 at <http://elilo.sourceforge.net> in order to take advantage
1937 of EFI runtime services. However, even with this option, the
1938 resultant kernel should continue to boot on existing non-EFI
1939 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001940
Matt Fleming291f3632011-12-12 21:27:52 +00001941config EFI_STUB
1942 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001943 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001944 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001945 ---help---
1946 This kernel feature allows a bzImage to be loaded directly
1947 by EFI firmware without the use of a bootloader.
1948
Roy Franz4172fe22013-09-22 15:45:25 -07001949 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001950
Matt Fleming7d453ee2014-01-10 18:52:06 +00001951config EFI_MIXED
1952 bool "EFI mixed-mode support"
1953 depends on EFI_STUB && X86_64
1954 ---help---
1955 Enabling this feature allows a 64-bit kernel to be booted
1956 on a 32-bit firmware, provided that your CPU supports 64-bit
1957 mode.
1958
1959 Note that it is not possible to boot a mixed-mode enabled
1960 kernel via the EFI boot stub - a bootloader that supports
1961 the EFI handover protocol must be used.
1962
1963 If unsure, say N.
1964
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001965config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001966 def_bool y
1967 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001968 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001969 This kernel feature is useful for number crunching applications
1970 that may need to compute untrusted bytecode during their
1971 execution. By using pipes or other transports made available to
1972 the process as file descriptors supporting the read/write
1973 syscalls, it's possible to isolate those applications in
1974 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001975 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001976 and the task is only allowed to execute a few safe syscalls
1977 defined by each seccomp mode.
1978
1979 If unsure, say Y. Only embedded should say N here.
1980
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001981source kernel/Kconfig.hz
1982
1983config KEXEC
1984 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001985 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001986 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001987 kexec is a system call that implements the ability to shutdown your
1988 current kernel, and to start another kernel. It is like a reboot
1989 but it is independent of the system firmware. And like a reboot
1990 you can start any kernel with it, not just Linux.
1991
1992 The name comes from the similarity to the exec system call.
1993
1994 It is an ongoing process to be certain the hardware in a machine
1995 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001996 initially work for you. As of this writing the exact hardware
1997 interface is strongly in flux, so no good recommendation can be
1998 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001999
Vivek Goyal74ca3172014-08-29 15:18:46 -07002000config KEXEC_FILE
2001 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07002002 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07002003 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07002004 depends on X86_64
2005 depends on CRYPTO=y
2006 depends on CRYPTO_SHA256=y
2007 ---help---
2008 This is new version of kexec system call. This system call is
2009 file based and takes file descriptors as system call argument
2010 for kernel and initramfs as opposed to list of segments as
2011 accepted by previous system call.
2012
AKASHI Takahirob799a092018-04-13 15:35:45 -07002013config ARCH_HAS_KEXEC_PURGATORY
2014 def_bool KEXEC_FILE
2015
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002016config KEXEC_VERIFY_SIG
2017 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07002018 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002019 ---help---
2020 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002021 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002022
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002023 In addition to that option, you need to enable signature
2024 verification for the corresponding kernel image type being
2025 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002026
2027config KEXEC_BZIMAGE_VERIFY_SIG
2028 bool "Enable bzImage signature verification support"
2029 depends on KEXEC_VERIFY_SIG
2030 depends on SIGNED_PE_FILE_VERIFICATION
2031 select SYSTEM_TRUSTED_KEYRING
2032 ---help---
2033 Enable bzImage signature verification support.
2034
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002035config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002036 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002037 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002038 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002039 Generate crash dump after being started by kexec.
2040 This should be normally only set in special crash dump kernels
2041 which are loaded in the main kernel with kexec-tools into
2042 a specially reserved region and then later executed after
2043 a crash by kdump/kexec. The crash dump kernel must be compiled
2044 to a memory address not used by the main kernel or BIOS using
2045 PHYSICAL_START, or it must be built as a relocatable image
2046 (CONFIG_RELOCATABLE=y).
2047 For more details see Documentation/kdump/kdump.txt
2048
Huang Ying3ab83522008-07-25 19:45:07 -07002049config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002050 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002051 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002052 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07002053 Jump between original kernel and kexeced kernel and invoke
2054 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002055
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002056config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002057 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002058 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002059 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002060 This gives the physical address where the kernel is loaded.
2061
2062 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2063 bzImage will decompress itself to above physical address and
2064 run from there. Otherwise, bzImage will run from the address where
2065 it has been loaded by the boot loader and will ignore above physical
2066 address.
2067
2068 In normal kdump cases one does not have to set/change this option
2069 as now bzImage can be compiled as a completely relocatable image
2070 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2071 address. This option is mainly useful for the folks who don't want
2072 to use a bzImage for capturing the crash dump and want to use a
2073 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2074 to be specifically compiled to run from a specific memory area
2075 (normally a reserved region) and this option comes handy.
2076
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002077 So if you are using bzImage for capturing the crash dump,
2078 leave the value here unchanged to 0x1000000 and set
2079 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2080 for capturing the crash dump change this value to start of
2081 the reserved region. In other words, it can be set based on
2082 the "X" value as specified in the "crashkernel=YM@XM"
2083 command line boot parameter passed to the panic-ed
2084 kernel. Please take a look at Documentation/kdump/kdump.txt
2085 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002086
2087 Usage of bzImage for capturing the crash dump is recommended as
2088 one does not have to build two kernels. Same kernel can be used
2089 as production kernel and capture kernel. Above option should have
2090 gone away after relocatable bzImage support is introduced. But it
2091 is present because there are users out there who continue to use
2092 vmlinux for dump capture. This option should go away down the
2093 line.
2094
2095 Don't change this unless you know what you are doing.
2096
2097config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002098 bool "Build a relocatable kernel"
2099 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002100 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002101 This builds a kernel image that retains relocation information
2102 so it can be loaded someplace besides the default 1MB.
2103 The relocations tend to make the kernel binary about 10% larger,
2104 but are discarded at runtime.
2105
2106 One use is for the kexec on panic case where the recovery kernel
2107 must live at a different physical address than the primary
2108 kernel.
2109
2110 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2111 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002112 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002113
Kees Cook8ab38202013-10-10 17:18:14 -07002114config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002115 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002116 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002117 default y
Kees Cook8ab38202013-10-10 17:18:14 -07002118 ---help---
Baoquan Hee8581e32016-04-20 13:55:43 -07002119 In support of Kernel Address Space Layout Randomization (KASLR),
2120 this randomizes the physical address at which the kernel image
2121 is decompressed and the virtual address where the kernel
2122 image is mapped, as a security feature that deters exploit
2123 attempts relying on knowledge of the location of kernel
2124 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002125
Kees Cooked9f0072016-05-25 15:45:33 -07002126 On 64-bit, the kernel physical and virtual addresses are
2127 randomized separately. The physical address will be anywhere
2128 between 16MB and the top of physical memory (up to 64TB). The
2129 virtual address will be randomized from 16MB up to 1GB (9 bits
2130 of entropy). Note that this also reduces the memory space
2131 available to kernel modules from 1.5GB to 1GB.
2132
2133 On 32-bit, the kernel physical and virtual addresses are
2134 randomized together. They will be randomized from 16MB up to
2135 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002136
Baoquan Hee8581e32016-04-20 13:55:43 -07002137 Entropy is generated using the RDRAND instruction if it is
2138 supported. If RDTSC is supported, its value is mixed into
2139 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002140 supported, then entropy is read from the i8254 timer. The
2141 usable entropy is limited by the kernel being built using
2142 2GB addressing, and that PHYSICAL_ALIGN must be at a
2143 minimum of 2MB. As a result, only 10 bits of entropy are
2144 theoretically possible, but the implementations are further
2145 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002146
Ingo Molnar6807c842017-04-18 11:08:12 +02002147 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002148
2149# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002150config X86_NEED_RELOCS
2151 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002152 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002153
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002154config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002155 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002156 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002157 range 0x2000 0x1000000 if X86_32
2158 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002159 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002160 This value puts the alignment restrictions on physical address
2161 where kernel is loaded and run from. Kernel is compiled for an
2162 address which meets above alignment restriction.
2163
2164 If bootloader loads the kernel at a non-aligned address and
2165 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2166 address aligned to above value and run from there.
2167
2168 If bootloader loads the kernel at a non-aligned address and
2169 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2170 load address and decompress itself to the address it has been
2171 compiled for and run from there. The address for which kernel is
2172 compiled already meets above alignment restrictions. Hence the
2173 end result is that kernel runs from a physical address meeting
2174 above alignment restrictions.
2175
Kees Cooka0215062013-07-08 09:15:17 -07002176 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2177 this value must be a multiple of 0x200000.
2178
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002179 Don't change this unless you know what you are doing.
2180
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002181config DYNAMIC_MEMORY_LAYOUT
2182 bool
2183 ---help---
2184 This option makes base addresses of vmalloc and vmemmap as well as
2185 __PAGE_OFFSET movable during boot.
2186
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002187config RANDOMIZE_MEMORY
2188 bool "Randomize the kernel memory sections"
2189 depends on X86_64
2190 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002191 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002192 default RANDOMIZE_BASE
2193 ---help---
2194 Randomizes the base virtual address of kernel memory sections
2195 (physical memory mapping, vmalloc & vmemmap). This security feature
2196 makes exploits relying on predictable memory locations less reliable.
2197
2198 The order of allocations remains unchanged. Entropy is generated in
2199 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2200 configuration have in average 30,000 different possible virtual
2201 addresses for each memory section.
2202
Ingo Molnar6807c842017-04-18 11:08:12 +02002203 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002204
Thomas Garnier90397a42016-06-21 17:47:06 -07002205config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2206 hex "Physical memory mapping padding" if EXPERT
2207 depends on RANDOMIZE_MEMORY
2208 default "0xa" if MEMORY_HOTPLUG
2209 default "0x0"
2210 range 0x1 0x40 if MEMORY_HOTPLUG
2211 range 0x0 0x40
2212 ---help---
2213 Define the padding in terabytes added to the existing physical
2214 memory size during kernel memory randomization. It is useful
2215 for memory hotplug support but reduces the entropy available for
2216 address randomization.
2217
2218 If unsure, leave at the default value.
2219
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002220config HOTPLUG_CPU
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002221 bool "Support for hot-pluggable CPUs"
Stephen Rothwell40b31362013-05-21 13:49:35 +10002222 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002223 ---help---
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002224 Say Y here to allow turning CPUs off and on. CPUs can be
2225 controlled through /sys/devices/system/cpu.
2226 ( Note: power management support will enable this option
2227 automatically on SMP systems. )
2228 Say N if you want to disable CPU hotplug.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002229
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002230config BOOTPARAM_HOTPLUG_CPU0
2231 bool "Set default setting of cpu0_hotpluggable"
2232 default n
Kees Cook2c922cd2013-01-22 13:01:19 -08002233 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002234 ---help---
2235 Set whether default state of cpu0_hotpluggable is on or off.
2236
2237 Say Y here to enable CPU0 hotplug by default. If this switch
2238 is turned on, there is no need to give cpu0_hotplug kernel
2239 parameter and the CPU0 hotplug feature is enabled by default.
2240
2241 Please note: there are two known CPU0 dependencies if you want
2242 to enable the CPU0 hotplug feature either by this switch or by
2243 cpu0_hotplug kernel parameter.
2244
2245 First, resume from hibernate or suspend always starts from CPU0.
2246 So hibernate and suspend are prevented if CPU0 is offline.
2247
2248 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2249 offline if any interrupt can not migrate out of CPU0. There may
2250 be other CPU0 dependencies.
2251
2252 Please make sure the dependencies are under your control before
2253 you enable this feature.
2254
2255 Say N if you don't want to enable CPU0 hotplug feature by default.
2256 You still can enable the CPU0 hotplug feature at boot by kernel
2257 parameter cpu0_hotplug.
2258
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002259config DEBUG_HOTPLUG_CPU0
2260 def_bool n
2261 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002262 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002263 ---help---
2264 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2265 soon as possible and boots up userspace with CPU0 offlined. User
2266 can online CPU0 back after boot time.
2267
2268 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2269 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2270 compilation or giving cpu0_hotplug kernel parameter at boot.
2271
2272 If unsure, say N.
2273
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002274config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002275 def_bool n
2276 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002277 depends on COMPAT_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002278 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002279 Certain buggy versions of glibc will crash if they are
2280 presented with a 32-bit vDSO that is not mapped at the address
2281 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002282
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002283 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2284 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2285 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2286 the only released version with the bug, but OpenSUSE 9
2287 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002288
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002289 The symptom of the bug is that everything crashes on startup, saying:
2290 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2291
2292 Saying Y here changes the default value of the vdso32 boot
2293 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2294 This works around the glibc bug but hurts performance.
2295
2296 If unsure, say N: if you are compiling your own kernel, you
2297 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002298
Kees Cook3dc33bd2015-08-12 17:55:19 -07002299choice
2300 prompt "vsyscall table for legacy applications"
2301 depends on X86_64
2302 default LEGACY_VSYSCALL_EMULATE
2303 help
2304 Legacy user code that does not know how to find the vDSO expects
2305 to be able to issue three syscalls by calling fixed addresses in
2306 kernel space. Since this location is not randomized with ASLR,
2307 it can be used to assist security vulnerability exploitation.
2308
2309 This setting can be changed at boot time via the kernel command
Andy Lutomirski076ca272018-03-07 11:12:27 -08002310 line parameter vsyscall=[emulate|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002311
2312 On a system with recent enough glibc (2.14 or newer) and no
2313 static binaries, you can say None without a performance penalty
2314 to improve security.
2315
2316 If unsure, select "Emulate".
2317
Kees Cook3dc33bd2015-08-12 17:55:19 -07002318 config LEGACY_VSYSCALL_EMULATE
2319 bool "Emulate"
2320 help
2321 The kernel traps and emulates calls into the fixed
2322 vsyscall address mapping. This makes the mapping
2323 non-executable, but it still contains known contents,
2324 which could be used in certain rare security vulnerability
2325 exploits. This configuration is recommended when userspace
2326 still uses the vsyscall area.
2327
2328 config LEGACY_VSYSCALL_NONE
2329 bool "None"
2330 help
2331 There will be no vsyscall mapping at all. This will
2332 eliminate any risk of ASLR bypass due to the vsyscall
2333 fixed address mapping. Attempts to use the vsyscalls
2334 will be reported to dmesg, so that either old or
2335 malicious userspace programs can be identified.
2336
2337endchoice
2338
Tim Bird516cbf32008-08-12 12:52:36 -07002339config CMDLINE_BOOL
2340 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002341 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002342 Allow for specifying boot arguments to the kernel at
2343 build time. On some systems (e.g. embedded ones), it is
2344 necessary or convenient to provide some or all of the
2345 kernel boot arguments with the kernel itself (that is,
2346 to not rely on the boot loader to provide them.)
2347
2348 To compile command line arguments into the kernel,
2349 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002350 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002351
2352 Systems with fully functional boot loaders (i.e. non-embedded)
2353 should leave this option set to 'N'.
2354
2355config CMDLINE
2356 string "Built-in kernel command string"
2357 depends on CMDLINE_BOOL
2358 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002359 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002360 Enter arguments here that should be compiled into the kernel
2361 image and used at boot time. If the boot loader provides a
2362 command line at boot time, it is appended to this string to
2363 form the full kernel command line, when the system boots.
2364
2365 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2366 change this behavior.
2367
2368 In most cases, the command line (whether built-in or provided
2369 by the boot loader) should specify the device for the root
2370 file system.
2371
2372config CMDLINE_OVERRIDE
2373 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002374 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002375 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002376 Set this option to 'Y' to have the kernel ignore the boot loader
2377 command line, and use ONLY the built-in command line.
2378
2379 This is used to work around broken boot loaders. This should
2380 be set to 'N' under normal conditions.
2381
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002382config MODIFY_LDT_SYSCALL
2383 bool "Enable the LDT (local descriptor table)" if EXPERT
2384 default y
2385 ---help---
2386 Linux can allow user programs to install a per-process x86
2387 Local Descriptor Table (LDT) using the modify_ldt(2) system
2388 call. This is required to run 16-bit or segmented code such as
2389 DOSEMU or some Wine programs. It is also used by some very old
2390 threading libraries.
2391
2392 Enabling this feature adds a small amount of overhead to
2393 context switches and increases the low-level kernel attack
2394 surface. Disabling it removes the modify_ldt(2) system call.
2395
2396 Saying 'N' here may make sense for embedded or server kernels.
2397
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002398source "kernel/livepatch/Kconfig"
2399
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002400endmenu
2401
Michal Hocko3072e412017-09-08 16:11:39 -07002402config ARCH_HAS_ADD_PAGES
2403 def_bool y
2404 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2405
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002406config ARCH_ENABLE_MEMORY_HOTPLUG
2407 def_bool y
2408 depends on X86_64 || (X86_32 && HIGHMEM)
2409
Gary Hade35551052008-10-31 10:52:03 -07002410config ARCH_ENABLE_MEMORY_HOTREMOVE
2411 def_bool y
2412 depends on MEMORY_HOTPLUG
2413
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002414config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002415 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002416 depends on NUMA
2417
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002418config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2419 def_bool y
2420 depends on X86_64 || X86_PAE
2421
Naoya Horiguchic177c812014-06-04 16:05:35 -07002422config ARCH_ENABLE_HUGEPAGE_MIGRATION
2423 def_bool y
2424 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2425
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002426config ARCH_ENABLE_THP_MIGRATION
2427 def_bool y
2428 depends on X86_64 && TRANSPARENT_HUGEPAGE
2429
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002430menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002431
2432config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002433 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002434 depends on X86_64 && HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002435
2436source "kernel/power/Kconfig"
2437
2438source "drivers/acpi/Kconfig"
2439
Feng Tangefafc8b2009-08-14 15:23:29 -04002440source "drivers/sfi/Kconfig"
2441
Andi Kleena6b68072008-01-30 13:32:49 +01002442config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002443 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002444 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002445
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002446menuconfig APM
2447 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002448 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002449 ---help---
2450 APM is a BIOS specification for saving power using several different
2451 techniques. This is mostly useful for battery powered laptops with
2452 APM compliant BIOSes. If you say Y here, the system time will be
2453 reset after a RESUME operation, the /proc/apm device will provide
2454 battery status information, and user-space programs will receive
2455 notification of APM "events" (e.g. battery status change).
2456
2457 If you select "Y" here, you can disable actual use of the APM
2458 BIOS by passing the "apm=off" option to the kernel at boot time.
2459
2460 Note that the APM support is almost completely disabled for
2461 machines with more than one CPU.
2462
2463 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002464 and more information, read <file:Documentation/power/apm-acpi.txt>
2465 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002466 <http://www.tldp.org/docs.html#howto>.
2467
2468 This driver does not spin down disk drives (see the hdparm(8)
2469 manpage ("man 8 hdparm") for that), and it doesn't turn off
2470 VESA-compliant "green" monitors.
2471
2472 This driver does not support the TI 4000M TravelMate and the ACER
2473 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2474 desktop machines also don't have compliant BIOSes, and this driver
2475 may cause those machines to panic during the boot phase.
2476
2477 Generally, if you don't have a battery in your machine, there isn't
2478 much point in using this driver and you should say N. If you get
2479 random kernel OOPSes or reboots that don't seem to be related to
2480 anything, try disabling/enabling this option (or disabling/enabling
2481 APM in your BIOS).
2482
2483 Some other things you should try when experiencing seemingly random,
2484 "weird" problems:
2485
2486 1) make sure that you have enough swap space and that it is
2487 enabled.
2488 2) pass the "no-hlt" option to the kernel
2489 3) switch on floating point emulation in the kernel and pass
2490 the "no387" option to the kernel
2491 4) pass the "floppy=nodma" option to the kernel
2492 5) pass the "mem=4M" option to the kernel (thereby disabling
2493 all but the first 4 MB of RAM)
2494 6) make sure that the CPU is not over clocked.
2495 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2496 8) disable the cache from your BIOS settings
2497 9) install a fan for the video card or exchange video RAM
2498 10) install a better fan for the CPU
2499 11) exchange RAM chips
2500 12) exchange the motherboard.
2501
2502 To compile this driver as a module, choose M here: the
2503 module will be called apm.
2504
2505if APM
2506
2507config APM_IGNORE_USER_SUSPEND
2508 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002509 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002510 This option will ignore USER SUSPEND requests. On machines with a
2511 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2512 series notebooks, it is necessary to say Y because of a BIOS bug.
2513
2514config APM_DO_ENABLE
2515 bool "Enable PM at boot time"
2516 ---help---
2517 Enable APM features at boot time. From page 36 of the APM BIOS
2518 specification: "When disabled, the APM BIOS does not automatically
2519 power manage devices, enter the Standby State, enter the Suspend
2520 State, or take power saving steps in response to CPU Idle calls."
2521 This driver will make CPU Idle calls when Linux is idle (unless this
2522 feature is turned off -- see "Do CPU IDLE calls", below). This
2523 should always save battery power, but more complicated APM features
2524 will be dependent on your BIOS implementation. You may need to turn
2525 this option off if your computer hangs at boot time when using APM
2526 support, or if it beeps continuously instead of suspending. Turn
2527 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2528 T400CDT. This is off by default since most machines do fine without
2529 this feature.
2530
2531config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002532 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002533 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002534 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002535 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2536 On some machines, this can activate improved power savings, such as
2537 a slowed CPU clock rate, when the machine is idle. These idle calls
2538 are made after the idle loop has run for some length of time (e.g.,
2539 333 mS). On some machines, this will cause a hang at boot time or
2540 whenever the CPU becomes idle. (On machines with more than one CPU,
2541 this option does nothing.)
2542
2543config APM_DISPLAY_BLANK
2544 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002545 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002546 Enable console blanking using the APM. Some laptops can use this to
2547 turn off the LCD backlight when the screen blanker of the Linux
2548 virtual console blanks the screen. Note that this is only used by
2549 the virtual console screen blanker, and won't turn off the backlight
2550 when using the X Window system. This also doesn't have anything to
2551 do with your VESA-compliant power-saving monitor. Further, this
2552 option doesn't work for all laptops -- it might not turn off your
2553 backlight at all, or it might print a lot of errors to the console,
2554 especially if you are using gpm.
2555
2556config APM_ALLOW_INTS
2557 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002558 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002559 Normally we disable external interrupts while we are making calls to
2560 the APM BIOS as a measure to lessen the effects of a badly behaving
2561 BIOS implementation. The BIOS should reenable interrupts if it
2562 needs to. Unfortunately, some BIOSes do not -- especially those in
2563 many of the newer IBM Thinkpads. If you experience hangs when you
2564 suspend, try setting this to Y. Otherwise, say N.
2565
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002566endif # APM
2567
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002568source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002569
2570source "drivers/cpuidle/Kconfig"
2571
Andy Henroid27471fd2008-10-09 11:45:22 -07002572source "drivers/idle/Kconfig"
2573
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002574endmenu
2575
2576
2577menu "Bus options (PCI etc.)"
2578
2579config PCI
Ingo Molnar1ac97012008-05-19 14:10:14 +02002580 bool "PCI support"
Adrian Bunk1c858082008-01-30 13:32:32 +01002581 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002582 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002583 Find out whether you have a PCI motherboard. PCI is the name of a
2584 bus system, i.e. the way the CPU talks to the other stuff inside
2585 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2586 VESA. If you have PCI, say Y, otherwise N.
2587
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002588choice
2589 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002590 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002591 default PCI_GOANY
2592 ---help---
2593 On PCI systems, the BIOS can be used to detect the PCI devices and
2594 determine their configuration. However, some old PCI motherboards
2595 have BIOS bugs and may crash if this is done. Also, some embedded
2596 PCI-based systems don't have any BIOS at all. Linux can also try to
2597 detect the PCI hardware directly without using the BIOS.
2598
2599 With this option, you can specify how Linux should detect the
2600 PCI devices. If you choose "BIOS", the BIOS will be used,
2601 if you choose "Direct", the BIOS won't be used, and if you
2602 choose "MMConfig", then PCI Express MMCONFIG will be used.
2603 If you choose "Any", the kernel will try MMCONFIG, then the
2604 direct access method and falls back to the BIOS if that doesn't
2605 work. If unsure, go with the default, which is "Any".
2606
2607config PCI_GOBIOS
2608 bool "BIOS"
2609
2610config PCI_GOMMCONFIG
2611 bool "MMConfig"
2612
2613config PCI_GODIRECT
2614 bool "Direct"
2615
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002616config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002617 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002618 depends on OLPC
2619
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002620config PCI_GOANY
2621 bool "Any"
2622
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002623endchoice
2624
2625config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002626 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002627 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002628
2629# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2630config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002631 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002632 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002633
2634config PCI_MMCONFIG
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002635 bool "Support mmconfig PCI config space access" if X86_64
2636 default y
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002637 depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002638 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002639
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002640config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002641 def_bool y
2642 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002643
Alex Nixonb5401a92010-03-18 16:31:34 -04002644config PCI_XEN
2645 def_bool y
2646 depends on PCI && XEN
2647 select SWIOTLB_XEN
2648
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002649config PCI_DOMAINS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002650 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002651 depends on PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002652
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002653config MMCONF_FAM10H
2654 def_bool y
2655 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002656
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002657config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002658 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002659 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002660 help
2661 Read the PCI windows out of the CNB20LE host bridge. This allows
2662 PCI hotplug to work on systems with the CNB20LE chipset which do
2663 not have ACPI.
2664
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002665 There's no public spec for this chipset, and this functionality
2666 is known to be incomplete.
2667
2668 You should say N unless you know you need this.
2669
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002670source "drivers/pci/Kconfig"
2671
William Breathitt Gray3a495512016-05-27 18:08:27 -04002672config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002673 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002674 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002675 Expose ISA bus device drivers and options available for selection and
2676 configuration. Enable this option if your target machine has an ISA
2677 bus. ISA is an older system, displaced by PCI and newer bus
2678 architectures -- if your target machine is modern, it probably does
2679 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002680
2681 If unsure, say N.
2682
David Rientjes1c00f012011-03-22 16:34:59 -07002683# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002684config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002685 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2686 default y
2687 help
2688 Enables ISA-style DMA support for devices requiring such controllers.
2689 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002690
Linus Torvalds51e68d02016-05-21 10:25:19 -07002691if X86_32
2692
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002693config ISA
2694 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002695 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002696 Find out whether you have ISA slots on your motherboard. ISA is the
2697 name of a bus system, i.e. the way the CPU talks to the other stuff
2698 inside your box. Other bus systems are PCI, EISA, MicroChannel
2699 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2700 newer boards don't support it. If you have ISA, say Y, otherwise N.
2701
2702config EISA
2703 bool "EISA support"
2704 depends on ISA
2705 ---help---
2706 The Extended Industry Standard Architecture (EISA) bus was
2707 developed as an open alternative to the IBM MicroChannel bus.
2708
2709 The EISA bus provided some of the features of the IBM MicroChannel
2710 bus while maintaining backward compatibility with cards made for
2711 the older ISA bus. The EISA bus saw limited use between 1988 and
2712 1995 when it was made obsolete by the PCI bus.
2713
2714 Say Y here if you are building a kernel for an EISA-based machine.
2715
2716 Otherwise, say N.
2717
2718source "drivers/eisa/Kconfig"
2719
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002720config SCx200
2721 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002722 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002723 This provides basic support for National Semiconductor's
2724 (now AMD's) Geode processors. The driver probes for the
2725 PCI-IDs of several on-chip devices, so its a good dependency
2726 for other scx200_* drivers.
2727
2728 If compiled as a module, the driver is named scx200.
2729
2730config SCx200HR_TIMER
2731 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002732 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002733 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002734 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002735 This driver provides a clocksource built upon the on-chip
2736 27MHz high-resolution timer. Its also a workaround for
2737 NSC Geode SC-1100's buggy TSC, which loses time when the
2738 processor goes idle (as is done by the scheduler). The
2739 other workaround is idle=poll boot option.
2740
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002741config OLPC
2742 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002743 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002744 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002745 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002746 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002747 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002748 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002749 Add support for detecting the unique features of the OLPC
2750 XO hardware.
2751
Daniel Drakea3128582011-06-25 17:34:10 +01002752config OLPC_XO1_PM
2753 bool "OLPC XO-1 Power Management"
Daniel Drake97c4cb72011-06-25 17:34:11 +01002754 depends on OLPC && MFD_CS5535 && PM_SLEEP
Daniel Drakea3128582011-06-25 17:34:10 +01002755 select MFD_CORE
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002756 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002757 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002758
Daniel Drakecfee9592011-06-25 17:34:17 +01002759config OLPC_XO1_RTC
2760 bool "OLPC XO-1 Real Time Clock"
2761 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2762 ---help---
2763 Add support for the XO-1 real time clock, which can be used as a
2764 programmable wakeup source.
2765
Daniel Drake7feda8e2011-06-25 17:34:12 +01002766config OLPC_XO1_SCI
2767 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002768 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002769 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002770 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002771 ---help---
2772 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002773 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002774 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002775 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002776 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002777 - AC adapter status updates
2778 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002779
Daniel Drakea0f30f52011-06-25 17:34:18 +01002780config OLPC_XO15_SCI
2781 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002782 depends on OLPC && ACPI
2783 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002784 ---help---
2785 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2786 - EC-driven system wakeups
2787 - AC adapter status updates
2788 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002789
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002790config ALIX
2791 bool "PCEngines ALIX System Support (LED setup)"
2792 select GPIOLIB
2793 ---help---
2794 This option enables system support for the PCEngines ALIX.
2795 At present this just sets up LEDs for GPIO control on
2796 ALIX2/3/6 boards. However, other system specific setup should
2797 get added here.
2798
2799 Note: You must still enable the drivers for GPIO and LED support
2800 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2801
2802 Note: You have to set alix.force=1 for boards with Award BIOS.
2803
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002804config NET5501
2805 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2806 select GPIOLIB
2807 ---help---
2808 This option enables system support for the Soekris Engineering net5501.
2809
Philip A. Prindeville31970592012-01-14 01:45:39 -07002810config GEOS
2811 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2812 select GPIOLIB
2813 depends on DMI
2814 ---help---
2815 This option enables system support for the Traverse Technologies GEOS.
2816
Vivien Didelot7d029122013-01-04 16:18:14 -05002817config TS5500
2818 bool "Technologic Systems TS-5500 platform support"
2819 depends on MELAN
2820 select CHECK_SIGNATURE
2821 select NEW_LEDS
2822 select LEDS_CLASS
2823 ---help---
2824 This option enables system support for the Technologic Systems TS-5500.
2825
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002826endif # X86_32
2827
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002828config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002829 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002830 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002831
2832source "drivers/pcmcia/Kconfig"
2833
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002834config RAPIDIO
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002835 tristate "RapidIO support"
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002836 depends on PCI
2837 default n
2838 help
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002839 If enabled this option will include drivers and the core
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002840 infrastructure code to support RapidIO interconnect devices.
2841
2842source "drivers/rapidio/Kconfig"
2843
David Herrmanne3263ab2013-08-02 14:05:22 +02002844config X86_SYSFB
2845 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2846 help
2847 Firmwares often provide initial graphics framebuffers so the BIOS,
2848 bootloader or kernel can show basic video-output during boot for
2849 user-guidance and debugging. Historically, x86 used the VESA BIOS
2850 Extensions and EFI-framebuffers for this, which are mostly limited
2851 to x86.
2852 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2853 framebuffers so the new generic system-framebuffer drivers can be
2854 used on x86. If the framebuffer is not compatible with the generic
2855 modes, it is adverticed as fallback platform framebuffer so legacy
2856 drivers like efifb, vesafb and uvesafb can pick it up.
2857 If this option is not selected, all system framebuffers are always
2858 marked as fallback platform framebuffers as usual.
2859
2860 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2861 not be able to pick up generic system framebuffers if this option
2862 is selected. You are highly encouraged to enable simplefb as
2863 replacement if you select this option. simplefb can correctly deal
2864 with generic system framebuffers. But you should still keep vesafb
2865 and others enabled as fallback if a system framebuffer is
2866 incompatible with simplefb.
2867
2868 If unsure, say Y.
2869
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002870endmenu
2871
2872
2873menu "Executable file formats / Emulations"
2874
2875source "fs/Kconfig.binfmt"
2876
2877config IA32_EMULATION
2878 bool "IA32 Emulation"
2879 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002880 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002881 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002882 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002883 select COMPAT_OLD_SIGACTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002884 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002885 Include code to run legacy 32-bit programs under a
2886 64-bit kernel. You should likely turn this on, unless you're
2887 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002888
2889config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002890 tristate "IA32 a.out support"
2891 depends on IA32_EMULATION
2892 ---help---
2893 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002894
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002895config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002896 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002897 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002898 ---help---
2899 Include code to run binaries for the x32 native 32-bit ABI
2900 for 64-bit processors. An x32 process gets access to the
2901 full 64-bit register file and wide data path while leaving
2902 pointers at 32 bits for smaller memory footprint.
2903
2904 You will need a recent binutils (2.22 or later) with
2905 elf32_x86_64 support enabled to compile a kernel with this
2906 option set.
2907
Ingo Molnar953fee12016-11-15 10:22:52 +01002908config COMPAT_32
2909 def_bool y
2910 depends on IA32_EMULATION || X86_32
2911 select HAVE_UID16
2912 select OLD_SIGSUSPEND3
2913
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002914config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002915 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002916 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002917
Jan Beulich3120e252012-09-10 12:41:45 +01002918if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002919config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002920 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002921
2922config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002923 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002924 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002925endif
David Howellsee009e4a02011-03-07 15:06:20 +00002926
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002927endmenu
2928
2929
Keith Packarde5beae12008-11-03 18:21:45 +01002930config HAVE_ATOMIC_IOMAP
2931 def_bool y
2932 depends on X86_32
2933
Alessandro Rubini4692d772012-04-04 19:39:58 +02002934config X86_DEV_DMA_OPS
2935 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002936 depends on X86_64 || STA2X11
Alessandro Rubini4692d772012-04-04 19:39:58 +02002937
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002938config X86_DMA_REMAP
2939 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002940 depends on STA2X11
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002941
Kirill A. Shutemove5855132017-06-06 14:31:20 +03002942config HAVE_GENERIC_GUP
2943 def_bool y
2944
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002945source "net/Kconfig"
2946
2947source "drivers/Kconfig"
2948
2949source "drivers/firmware/Kconfig"
2950
2951source "fs/Kconfig"
2952
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002953source "arch/x86/Kconfig.debug"
2954
2955source "security/Kconfig"
2956
2957source "crypto/Kconfig"
2958
Avi Kivityedf88412007-12-16 11:02:48 +02002959source "arch/x86/kvm/Kconfig"
2960
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002961source "lib/Kconfig"