blob: 1f5fa2f2c1684c6452b3357ada5997ec84d958fd [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
Daniel Micay6974f0c2017-07-12 14:36:10 -070055 select ARCH_HAS_FORTIFY_SOURCE
Riku Voipio957e3fa2014-12-12 16:57:44 -080056 select ARCH_HAS_GCOV_PROFILE_ALL
Dmitry Vyukov5c9a8752016-03-22 14:27:30 -070057 select ARCH_HAS_KCOV if X86_64
Mathieu Desnoyers10bcc802018-01-29 15:20:18 -050058 select ARCH_HAS_MEMBARRIER_SYNC_CORE
Ingo Molnarc763ea22016-11-15 10:26:39 +010059 select ARCH_HAS_PMEM_API if X86_64
Kees Cook39208aa2017-09-02 13:09:46 -070060 select ARCH_HAS_REFCOUNT
Dan Williams0aed55a2017-05-29 12:22:50 -070061 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Daniel Borkmannd2852a22017-02-21 16:09:33 +010062 select ARCH_HAS_SET_MEMORY
Ingo Molnar6471b822015-06-03 10:00:13 +020063 select ARCH_HAS_SG_CHAIN
Laura Abbottad21fc42017-02-06 16:31:57 -080064 select ARCH_HAS_STRICT_KERNEL_RWX
65 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050066 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Andrey Ryabininc6d30852016-01-20 15:00:55 -080067 select ARCH_HAS_UBSAN_SANITIZE_ALL
Oliver O'Halloran65f7d042017-06-28 11:32:31 +100068 select ARCH_HAS_ZONE_DEVICE if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020069 select ARCH_HAVE_NMI_SAFE_CMPXCHG
70 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040071 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080072 select ARCH_MIGHT_HAVE_PC_SERIO
Ingo Molnar6471b822015-06-03 10:00:13 +020073 select ARCH_SUPPORTS_ATOMIC_RMW
Ingo Molnar6471b822015-06-03 10:00:13 +020074 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
75 select ARCH_USE_BUILTIN_BSWAP
Ingo Molnar6471b822015-06-03 10:00:13 +020076 select ARCH_USE_QUEUED_RWLOCKS
77 select ARCH_USE_QUEUED_SPINLOCKS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -070078 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Ingo Molnarc763ea22016-11-15 10:26:39 +010079 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Huang Ying38d8b4e2017-07-06 15:37:18 -070080 select ARCH_WANTS_THP_SWAP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020081 select BUILDTIME_EXTABLE_SORT
82 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +020083 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
84 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +020085 select DCACHE_WORD_ACCESS
Christoph Hellwigfec777c2018-03-19 11:38:15 +010086 select DMA_DIRECT_OPS
Linus Torvalds45471cd2015-06-24 19:52:06 -070087 select EDAC_ATOMIC_SCRUB
88 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +020089 select GENERIC_CLOCKEVENTS
90 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
91 select GENERIC_CLOCKEVENTS_MIN_ADJUST
92 select GENERIC_CMOS_UPDATE
93 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +010094 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +020095 select GENERIC_EARLY_IOREMAP
96 select GENERIC_FIND_FIRST_BIT
97 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +020098 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +020099 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +0200100 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200101 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200102 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200103 select GENERIC_IRQ_SHOW
104 select GENERIC_PENDING_IRQ if SMP
105 select GENERIC_SMP_IDLE_THREAD
106 select GENERIC_STRNCPY_FROM_USER
107 select GENERIC_STRNLEN_USER
108 select GENERIC_TIME_VSYSCALL
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200109 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200110 select HAVE_ACPI_APEI if ACPI
111 select HAVE_ACPI_APEI_NMI if ACPI
112 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200113 select HAVE_ARCH_AUDITSYSCALL
114 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
115 select HAVE_ARCH_JUMP_LABEL
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800116 select HAVE_ARCH_KASAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200117 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800118 select HAVE_ARCH_MMAP_RND_BITS if MMU
119 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300120 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ingo Molnar6471b822015-06-03 10:00:13 +0200121 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700122 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Ingo Molnar6471b822015-06-03 10:00:13 +0200123 select HAVE_ARCH_TRACEHOOK
124 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Matthew Wilcoxa00cc7d2017-02-24 14:57:02 -0800125 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
Andy Lutomirskie37e43a2016-08-11 02:35:23 -0700126 select HAVE_ARCH_VMAP_STACK if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100127 select HAVE_ARCH_WITHIN_STACK_FRAMES
Ingo Molnar6471b822015-06-03 10:00:13 +0200128 select HAVE_CC_STACKPROTECTOR
129 select HAVE_CMPXCHG_DOUBLE
130 select HAVE_CMPXCHG_LOCAL
131 select HAVE_CONTEXT_TRACKING if X86_64
Josh Triplettc1bd55f2015-06-30 15:00:00 -0700132 select HAVE_COPY_THREAD_TLS
Ingo Molnar6471b822015-06-03 10:00:13 +0200133 select HAVE_C_RECORDMCOUNT
134 select HAVE_DEBUG_KMEMLEAK
135 select HAVE_DEBUG_STACKOVERFLOW
136 select HAVE_DMA_API_DEBUG
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
Wang YanQing03f57812018-05-03 14:10:43 +0800140 select HAVE_EBPF_JIT
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
Mike Travisdd5af902008-01-30 13:33:32 +0100276config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900277 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100278
Tejun Heo08fc4582009-08-14 15:00:49 +0900279config NEED_PER_CPU_EMBED_FIRST_CHUNK
280 def_bool y
281
282config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900283 def_bool y
284
Johannes Berg801e4062007-12-08 02:12:39 +0100285config ARCH_HIBERNATION_POSSIBLE
286 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100287
Johannes Bergf4cb5702007-12-08 02:14:00 +0100288config ARCH_SUSPEND_POSSIBLE
289 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100290
Steve Cappercfe28c52013-04-29 14:29:48 +0100291config ARCH_WANT_HUGE_PMD_SHARE
292 def_bool y
293
Steve Capper53313b22013-04-30 08:03:42 +0100294config ARCH_WANT_GENERAL_HUGETLB
295 def_bool y
296
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100297config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000298 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100299
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100300config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000301 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100302
Ingo Molnar765c68b2008-04-09 11:03:37 +0200303config ARCH_SUPPORTS_OPTIMIZED_INLINING
304 def_bool y
305
Akinobu Mita6a11f752009-03-31 15:23:17 -0700306config ARCH_SUPPORTS_DEBUG_PAGEALLOC
307 def_bool y
308
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300309config KASAN_SHADOW_OFFSET
310 hex
311 depends on KASAN
312 default 0xdffffc0000000000
313
Shane Wang69575d32009-09-01 18:25:07 -0700314config HAVE_INTEL_TXT
315 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700316 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700317
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100318config X86_32_SMP
319 def_bool y
320 depends on X86_32 && SMP
321
322config X86_64_SMP
323 def_bool y
324 depends on X86_64 && SMP
325
Tejun Heoccbeed32009-02-09 22:17:40 +0900326config X86_32_LAZY_GS
327 def_bool y
Kees Cook2bc2f682018-02-06 15:37:41 -0800328 depends on X86_32 && CC_STACKPROTECTOR_NONE
Tejun Heoccbeed32009-02-09 22:17:40 +0900329
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530330config ARCH_SUPPORTS_UPROBES
331 def_bool y
332
Rob Herringd20642f2014-04-18 17:19:54 -0500333config FIX_EARLYCON_MEM
334 def_bool y
335
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700336config PGTABLE_LEVELS
337 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300338 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700339 default 4 if X86_64
340 default 3 if X86_PAE
341 default 2
342
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100343source "init/Kconfig"
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700344source "kernel/Kconfig.freezer"
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100345
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100346menu "Processor type and features"
347
Randy Dunlap5ee71532012-01-16 11:57:18 -0800348config ZONE_DMA
349 bool "DMA memory allocation support" if EXPERT
350 default y
351 help
352 DMA memory allocation support allows devices with less than 32-bit
353 addressing to allocate within the first 16MB of address space.
354 Disable if no such devices will be used.
355
356 If unsure, say Y.
357
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100358config SMP
359 bool "Symmetric multi-processing support"
360 ---help---
361 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800362 a system with only one CPU, say N. If you have a system with more
363 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100364
Robert Graffham4a474152014-01-23 15:55:29 -0800365 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100366 machines, but will use only one CPU of a multiprocessor machine. If
367 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800368 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100369 will run faster if you say N here.
370
371 Note that if you say Y here and choose architecture "586" or
372 "Pentium" under "Processor family", the kernel will not work on 486
373 architectures. Similarly, multiprocessor kernels for the "PPro"
374 architecture may not work on all Pentium based boards.
375
376 People using multiprocessor machines who say Y here should also say
377 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
378 Management" code will be disabled if you say Y here.
379
Paul Bolle395cf962011-08-15 02:02:26 +0200380 See also <file:Documentation/x86/i386/IO-APIC.txt>,
Benjamin Petersonc9525a32017-05-20 17:20:16 -0700381 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100382 <http://www.tldp.org/docs.html#howto>.
383
384 If you don't know what to do here, say N.
385
Josh Triplett9def39be2013-10-30 08:09:45 -0700386config X86_FEATURE_NAMES
387 bool "Processor feature human-readable names" if EMBEDDED
388 default y
389 ---help---
390 This option compiles in a table of x86 feature bits and corresponding
391 names. This is required to support /proc/cpuinfo and a few kernel
392 messages. You can disable this to save space, at the expense of
393 making those few kernel messages show numeric feature bits instead.
394
395 If in doubt, say Y.
396
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800397config X86_X2APIC
398 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200399 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800400 ---help---
401 This enables x2apic support on CPUs that have this feature.
402
403 This allows 32-bit apic IDs (so it can support very large systems),
404 and accesses the local apic via MSRs not via mmio.
405
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800406 If you don't know what to do here, say N.
407
Yinghai Lu6695c852008-06-19 12:13:09 -0700408config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700409 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000410 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200411 depends on X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100412 ---help---
Yinghai Lu6695c852008-06-19 12:13:09 -0700413 For old smp systems that do not have proper acpi support. Newer systems
414 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700415
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000416config GOLDFISH
417 def_bool y
418 depends on X86_GOLDFISH
419
David Woodhouse76b04382018-01-11 21:46:25 +0000420config RETPOLINE
421 bool "Avoid speculative indirect branches in kernel"
422 default y
Peter Zijlstrad5028ba2018-02-06 09:46:13 +0100423 select STACK_VALIDATION if HAVE_STACK_VALIDATION
David Woodhouse76b04382018-01-11 21:46:25 +0000424 help
425 Compile kernel with the retpoline compiler options to guard against
426 kernel-to-user data leaks by avoiding speculative indirect
427 branches. Requires a compiler with -mindirect-branch=thunk-extern
428 support for full protection. The kernel may run slower.
429
430 Without compiler support, at least indirect branches in assembler
431 code are eliminated. Since this includes the syscall entry path,
432 it is not entirely pointless.
433
Vikas Shivappaf01d7d52017-07-25 14:14:22 -0700434config INTEL_RDT
435 bool "Intel Resource Director Technology support"
Fenghua Yu78e99b42016-10-22 06:19:53 -0700436 default n
437 depends on X86 && CPU_SUP_INTEL
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100438 select KERNFS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700439 help
Vikas Shivappaf01d7d52017-07-25 14:14:22 -0700440 Select to enable resource allocation and monitoring which are
441 sub-features of Intel Resource Director Technology(RDT). More
442 information about RDT can be found in the Intel x86
443 Architecture Software Developer Manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700444
445 Say N if unsure.
446
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800447if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800448config X86_BIGSMP
449 bool "Support for big SMP systems with more than 8 CPUs"
450 depends on SMP
451 ---help---
452 This option is needed for the systems that have more than 8 CPUs
453
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800454config X86_EXTENDED_PLATFORM
455 bool "Support for extended (non-PC) x86 platforms"
456 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100457 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100458 If you disable this option then the kernel will only support
459 standard PC platforms. (which covers the vast majority of
460 systems out there.)
461
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800462 If you enable this option then you'll be able to select support
463 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100464 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800465 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800466 RDC R-321x SoC
467 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200468 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200469 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100470
471 If you have one of these systems, or if you want to build a
472 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800473endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100474
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800475if X86_64
476config X86_EXTENDED_PLATFORM
477 bool "Support for extended (non-PC) x86 platforms"
478 default y
479 ---help---
480 If you disable this option then the kernel will only support
481 standard PC platforms. (which covers the vast majority of
482 systems out there.)
483
484 If you enable this option then you'll be able to select support
485 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800486 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800487 ScaleMP vSMP
488 SGI Ultraviolet
489
490 If you have one of these systems, or if you want to build a
491 generic distribution kernel, say Y here - otherwise say N.
492endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800493# This is an alphabetically sorted list of 64 bit extended platforms
494# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800495config X86_NUMACHIP
496 bool "Numascale NumaChip"
497 depends on X86_64
498 depends on X86_EXTENDED_PLATFORM
499 depends on NUMA
500 depends on SMP
501 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700502 depends on PCI_MMCONFIG
Steffen Persvold44b111b52011-12-06 00:07:26 +0800503 ---help---
504 Adds support for Numascale NumaChip large-SMP systems. Needed to
505 enable more than ~168 cores.
506 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100507
Ingo Molnar6a485652009-01-27 18:29:13 +0100508config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800509 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100510 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100511 select PARAVIRT
512 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800513 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300514 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100515 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100516 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
517 supposed to run on these EM64T-based machines. Only choose this option
518 if you have one of these machines.
519
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800520config X86_UV
521 bool "SGI Ultraviolet"
522 depends on X86_64
523 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500524 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800525 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700526 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200527 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800528 ---help---
529 This option is needed in order to support SGI Ultraviolet systems.
530 If you don't have one of these, you should say N here.
531
532# Following is an alphabetically sorted list of 32 bit extended platforms
533# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100534
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000535config X86_GOLDFISH
536 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100537 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000538 ---help---
539 Enable support for the Goldfish virtual platform used primarily
540 for Android development. Unless you are building for the Android
541 Goldfish emulator say N here.
542
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800543config X86_INTEL_CE
544 bool "CE4100 TV platform"
545 depends on PCI
546 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800547 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800548 depends on X86_32
549 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800550 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100551 select OF
552 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800553 ---help---
554 Select for the Intel CE media processor (CE4100) SOC.
555 This option compiles in support for the CE4100 SOC for settop
556 boxes and media devices.
557
David Cohen4cb9b002013-12-16 17:37:26 -0800558config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100559 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100560 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800561 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000562 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200563 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000564 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000565 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800566 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000567 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000568 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000569 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000570 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000571 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800572 Select to build a kernel capable of supporting Intel MID (Mobile
573 Internet Device) platform systems which do not have the PCI legacy
574 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000575
David Cohen4cb9b002013-12-16 17:37:26 -0800576 Intel MID platforms are based on an Intel processor and chipset which
577 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100578
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000579config X86_INTEL_QUARK
580 bool "Intel Quark platform support"
581 depends on X86_32
582 depends on X86_EXTENDED_PLATFORM
583 depends on X86_PLATFORM_DEVICES
584 depends on X86_TSC
585 depends on PCI
586 depends on PCI_GOANY
587 depends on X86_IO_APIC
588 select IOSF_MBI
589 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200590 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000591 ---help---
592 Select to include support for Quark X1000 SoC.
593 Say Y here if you have a Quark based system such as the Arduino
594 compatible Intel Galileo.
595
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000596config X86_INTEL_LPSS
597 bool "Intel Low Power Subsystem Support"
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100598 depends on X86 && ACPI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000599 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300600 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100601 select IOSF_MBI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000602 ---help---
603 Select to build support for Intel Low Power Subsystem such as
604 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300605 things like clock tree (common clock framework) and pincontrol
606 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000607
Ken Xue92082a82015-02-06 08:27:51 +0800608config X86_AMD_PLATFORM_DEVICE
609 bool "AMD ACPI2Platform devices support"
610 depends on ACPI
611 select COMMON_CLK
612 select PINCTRL
613 ---help---
614 Select to interpret AMD specific ACPI device to platform device
615 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
616 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
617 implemented under PINCTRL subsystem.
618
David E. Boxced3ce72014-09-17 22:13:50 -0700619config IOSF_MBI
620 tristate "Intel SoC IOSF Sideband support for SoC platforms"
621 depends on PCI
622 ---help---
623 This option enables sideband register access support for Intel SoC
624 platforms. On these platforms the IOSF sideband is used in lieu of
625 MSR's for some register accesses, mostly but not limited to thermal
626 and power. Drivers may query the availability of this device to
627 determine if they need the sideband in order to work on these
628 platforms. The sideband is available on the following SoC products.
629 This list is not meant to be exclusive.
630 - BayTrail
631 - Braswell
632 - Quark
633
634 You should say Y if you are running a kernel on one of these SoC's.
635
David E. Boxed2226b2014-09-17 22:13:51 -0700636config IOSF_MBI_DEBUG
637 bool "Enable IOSF sideband access through debugfs"
638 depends on IOSF_MBI && DEBUG_FS
639 ---help---
640 Select this option to expose the IOSF sideband access registers (MCR,
641 MDR, MCRX) through debugfs to write and read register information from
642 different units on the SoC. This is most useful for obtaining device
643 state information for debug and analysis. As this is a general access
644 mechanism, users of this option would have specific knowledge of the
645 device they want to access.
646
647 If you don't require the option or are in doubt, say N.
648
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800649config X86_RDC321X
650 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100651 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800652 depends on X86_EXTENDED_PLATFORM
653 select M486
654 select X86_REBOOTFIXUPS
655 ---help---
656 This option is needed for RDC R-321x system-on-chip, also known
657 as R-8610-(G).
658 If you don't have one of these chips, you should say N here.
659
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100660config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100661 bool "Support non-standard 32-bit SMP architectures"
662 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800663 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100664 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800665 This option compiles in the bigsmp and STA2X11 default
666 subarchitectures. It is intended for a generic binary
667 kernel. If you select them all, kernel will probe it one by
668 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700669
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800670# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700671
Linus Torvaldsd949f362009-09-26 09:35:07 -0700672config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100673 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700674 # MCE code calls memory_failure():
675 depends on X86_MCE
676 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700677 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
678 depends on X86_64 || !SPARSEMEM
679 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700680
Alessandro Rubini83125a32012-04-04 19:40:21 +0200681config STA2X11
682 bool "STA2X11 Companion Chip Support"
683 depends on X86_32_NON_STANDARD && PCI
Christoph Hellwigb6e05472018-03-19 11:38:24 +0100684 select ARCH_HAS_PHYS_TO_DMA
Alessandro Rubini83125a32012-04-04 19:40:21 +0200685 select X86_DEV_DMA_OPS
686 select X86_DMA_REMAP
687 select SWIOTLB
688 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200689 select GPIOLIB
Alessandro Rubini83125a32012-04-04 19:40:21 +0200690 default n
691 ---help---
692 This adds support for boards based on the STA2X11 IO-Hub,
693 a.k.a. "ConneXt". The chip is used in place of the standard
694 PC chipset, so all "standard" peripherals are missing. If this
695 option is selected the kernel will still be able to boot on
696 standard PC machines.
697
Shérab82148d12010-09-25 06:06:57 +0200698config X86_32_IRIS
699 tristate "Eurobraille/Iris poweroff module"
700 depends on X86_32
701 ---help---
702 The Iris machines from EuroBraille do not have APM or ACPI support
703 to shut themselves down properly. A special I/O sequence is
704 needed to do so, which is what this module does at
705 kernel shutdown.
706
707 This is only for Iris machines from EuroBraille.
708
709 If unused, say N.
710
Ingo Molnarae1e9132008-11-11 09:05:16 +0100711config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100712 def_bool y
713 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800714 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100715 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100716 Calculate simpler /proc/<PID>/wchan values. If this option
717 is disabled then wchan values will recurse back to the
718 caller function. This provides more accurate wchan values,
719 at the expense of slightly more scheduling overhead.
720
721 If in doubt, say "Y".
722
Borislav Petkov6276a072013-03-04 21:20:21 +0100723menuconfig HYPERVISOR_GUEST
724 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100725 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100726 Say Y here to enable options for running Linux under various hyper-
727 visors. This option enables basic hypervisor detection and platform
728 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100729
Borislav Petkov6276a072013-03-04 21:20:21 +0100730 If you say N, all options in this submenu will be skipped and
731 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100732
Borislav Petkov6276a072013-03-04 21:20:21 +0100733if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100734
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100735config PARAVIRT
736 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100737 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100738 This changes the kernel so it can modify itself when it is run
739 under a hypervisor, potentially improving performance significantly
740 over full virtualization. However, when run without a hypervisor
741 the kernel is theoretically slower and slightly larger.
742
Borislav Petkov6276a072013-03-04 21:20:21 +0100743config PARAVIRT_DEBUG
744 bool "paravirt-ops debugging"
745 depends on PARAVIRT && DEBUG_KERNEL
746 ---help---
747 Enable to debug paravirt_ops internals. Specifically, BUG if
748 a paravirt_op is missing when it is called.
749
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700750config PARAVIRT_SPINLOCKS
751 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700752 depends on PARAVIRT && SMP
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700753 ---help---
754 Paravirtualized spinlocks allow a pvops backend to replace the
755 spinlock implementation with something virtualization-friendly
756 (for example, block the virtual CPU rather than spinning).
757
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530758 It has a minimal impact on native kernels and gives a nice performance
759 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700760
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530761 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700762
Waiman Long45e898b2015-11-09 19:09:25 -0500763config QUEUED_LOCK_STAT
764 bool "Paravirt queued spinlock statistics"
Peter Zijlstracfd89832016-05-18 20:43:02 +0200765 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
Waiman Long45e898b2015-11-09 19:09:25 -0500766 ---help---
767 Enable the collection of statistical data on the slowpath
768 behavior of paravirtualized queued spinlocks and report
769 them on debugfs.
770
Borislav Petkov6276a072013-03-04 21:20:21 +0100771source "arch/x86/xen/Kconfig"
772
773config KVM_GUEST
774 bool "KVM Guest support (including kvmclock)"
775 depends on PARAVIRT
776 select PARAVIRT_CLOCK
777 default y
778 ---help---
779 This option enables various optimizations for running under the KVM
780 hypervisor. It includes a paravirtualized clock, so that instead
781 of relying on a PIT (or probably other) emulation by the
782 underlying device model, the host provides the guest with
783 timing infrastructure such as time of day, and system time
784
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530785config KVM_DEBUG_FS
786 bool "Enable debug information for KVM Guests in debugfs"
787 depends on KVM_GUEST && DEBUG_FS
788 default n
789 ---help---
790 This option enables collection of various statistics for KVM guest.
791 Statistics are displayed in debugfs filesystem. Enabling this option
792 may incur significant overhead.
793
Borislav Petkov6276a072013-03-04 21:20:21 +0100794config PARAVIRT_TIME_ACCOUNTING
795 bool "Paravirtual steal time accounting"
796 depends on PARAVIRT
797 default n
798 ---help---
799 Select this option to enable fine granularity task steal time
800 accounting. Time spent executing other tasks in parallel with
801 the current vCPU is discounted from the vCPU power. To account for
802 that, there can be a small performance impact.
803
804 If in doubt, say N here.
805
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200806config PARAVIRT_CLOCK
807 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200808
Jan Kiszka4a362602017-11-27 09:11:46 +0100809config JAILHOUSE_GUEST
810 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100811 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100812 select X86_PM_TIMER
Jan Kiszka4a362602017-11-27 09:11:46 +0100813 ---help---
814 This option allows to run Linux as guest in a Jailhouse non-root
815 cell. You can leave this option disabled if you only want to start
816 Jailhouse and run Linux afterwards in the root cell.
817
Borislav Petkov6276a072013-03-04 21:20:21 +0100818endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400819
Yinghai Lu08677212010-02-10 01:20:20 -0800820config NO_BOOTMEM
Yinghai Lu774ea0b2010-08-25 13:39:18 -0700821 def_bool y
Yinghai Lu08677212010-02-10 01:20:20 -0800822
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100823source "arch/x86/Kconfig.cpu"
824
825config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100826 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100827 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100828 ---help---
829 Use the IA-PC HPET (High Precision Event Timer) to manage
830 time in preference to the PIT and RTC, if a HPET is
831 present.
832 HPET is the next generation timer replacing legacy 8254s.
833 The HPET provides a stable time base on SMP
834 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200835 as it is off-chip. The interface used is documented
836 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100837
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100838 You can safely choose Y here. However, HPET will only be
839 activated if the platform and the BIOS support this feature.
840 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100841
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100842 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100843
844config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100845 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800846 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100847
Jacob Panbb24c472009-09-02 07:37:17 -0700848config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000849 def_bool y if X86_INTEL_MID
850 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100851 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000852 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700853 help
854 APB timer is the replacement for 8254, HPET on X86 MID platforms.
855 The APBT provides a stable time base on SMP
856 systems, unlike the TSC, but it is more expensive to access,
857 as it is off-chip. APB timers are always running regardless of CPU
858 C states, they are used as per CPU clockevent device when possible.
859
David Rientjes6a108a12011-01-20 14:44:16 -0800860# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100861# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700862config DMI
863 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800864 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800865 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100866 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700867 Enabled scanning of DMI to identify machine quirks. Say Y
868 here unless you have verified that your setup is not
869 affected by entries in the DMI blacklist. Required by PNP
870 BIOS code.
871
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100872config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700873 bool "Old AMD GART IOMMU support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100874 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200875 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100876 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200877 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
878 GART based hardware IOMMUs.
879
880 The GART supports full DMA access for devices with 32-bit access
881 limitations, on systems with more than 3 GB. This is usually needed
882 for USB, sound, many IDE/SATA chipsets and some other devices.
883
884 Newer systems typically have a modern AMD IOMMU, supported via
885 the CONFIG_AMD_IOMMU=y config option.
886
887 In normal configurations this driver is only active when needed:
888 there's more than 3 GB of memory and the system contains a
889 32-bit limited device.
890
891 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100892
893config CALGARY_IOMMU
894 bool "IBM Calgary IOMMU support"
895 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700896 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100897 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100898 Support for hardware IOMMUs in IBM's xSeries x366 and x460
899 systems. Needed to run systems with more than 3GB of memory
900 properly with 32-bit PCI devices that do not support DAC
901 (Double Address Cycle). Calgary also supports bus level
902 isolation, where all DMAs pass through the IOMMU. This
903 prevents them from going anywhere except their intended
904 destination. This catches hard-to-find kernel bugs and
905 mis-behaving drivers and devices that do not use the DMA-API
906 properly to set up their DMA buffers. The IOMMU can be
907 turned off at boot time with the iommu=off parameter.
908 Normally the kernel will make the right choice by itself.
909 If unsure, say Y.
910
911config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100912 def_bool y
913 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100914 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100915 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100916 Should Calgary be enabled by default? if you choose 'y', Calgary
917 will be used (if it exists). If you choose 'n', Calgary will not be
918 used even if it exists. If you choose 'n' and would like to use
919 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
920 If unsure, say Y.
921
922# need this always selected by IOMMU for the VIA workaround
923config SWIOTLB
Joerg Roedela1afd012008-11-18 12:44:21 +0100924 def_bool y if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100925 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100926 Support for software bounce buffers used on x86-64 systems
Joe Millenbach4454d322012-09-02 17:38:20 -0700927 which don't have a hardware IOMMU. Using this PCI devices
928 which can only access 32-bits of memory can be used on systems
929 with more than 3 GB of memory.
930 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100931
FUJITA Tomonoria8522502008-04-29 00:59:36 -0700932config IOMMU_HELPER
Jan Beulich3120e252012-09-10 12:41:45 +0100933 def_bool y
934 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
Linus Torvaldsd25e26b2008-08-25 14:15:38 -0700935
Mike Travis1184dc22008-05-12 21:21:12 +0200936config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200937 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700938 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800939 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100940 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200941 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200942 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100943
Ingo Molnaraec64872018-02-10 12:36:29 +0100944#
945# The maximum number of CPUs supported:
946#
947# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
948# and which can be configured interactively in the
949# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
950#
951# The ranges are different on 32-bit and 64-bit kernels, depending on
952# hardware capabilities and scalability features of the kernel.
953#
954# ( If MAXSMP is enabled we just use the highest possible value and disable
955# interactive configuration. )
956#
957
958config NR_CPUS_RANGE_BEGIN
959 int
960 default NR_CPUS_RANGE_END if MAXSMP
961 default 1 if !SMP
962 default 2
963
964config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800965 int
966 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100967 default 64 if SMP && X86_BIGSMP
968 default 8 if SMP && !X86_BIGSMP
969 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800970
Ingo Molnaraec64872018-02-10 12:36:29 +0100971config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800972 int
973 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100974 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
975 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
976 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800977
Ingo Molnaraec64872018-02-10 12:36:29 +0100978config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800979 int
980 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100981 default 32 if X86_BIGSMP
982 default 8 if SMP
983 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800984
Ingo Molnaraec64872018-02-10 12:36:29 +0100985config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800986 int
987 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100988 default 8192 if MAXSMP
989 default 64 if SMP
990 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800991
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100992config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800993 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +0100994 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
995 default NR_CPUS_DEFAULT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100996 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100997 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500998 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +0300999 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001000 minimum value which makes sense is 2.
1001
Ingo Molnaraec64872018-02-10 12:36:29 +01001002 This is purely to save memory: each supported CPU adds about 8KB
1003 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001004
1005config SCHED_SMT
1006 bool "SMT (Hyperthreading) scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001007 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001008 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001009 SMT scheduler support improves the CPU scheduler's decision making
1010 when dealing with Intel Pentium 4 chips with HyperThreading at a
1011 cost of slightly increased overhead in some places. If unsure say
1012 N here.
1013
1014config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001015 def_bool y
1016 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001017 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001018 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001019 Multi-core scheduler support improves the CPU scheduler's decision
1020 making when dealing with multi-core CPU chips at a cost of slightly
1021 increased overhead in some places. If unsure say N here.
1022
Tim Chende966cf2016-11-29 10:43:27 -08001023config SCHED_MC_PRIO
1024 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001025 depends on SCHED_MC && CPU_SUP_INTEL
1026 select X86_INTEL_PSTATE
1027 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001028 default y
Tim Chen5e76b2a2016-11-22 12:23:55 -08001029 ---help---
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001030 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1031 core ordering determined at manufacturing time, which allows
1032 certain cores to reach higher turbo frequencies (when running
1033 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001034
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001035 Enabling this kernel feature teaches the scheduler about
1036 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1037 scheduler's CPU selection logic accordingly, so that higher
1038 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001039
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001040 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001041
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001042 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001043
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001044source "kernel/Kconfig.preempt"
1045
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001046config UP_LATE_INIT
1047 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +01001048 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001049
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001050config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001051 bool "Local APIC support on uniprocessors" if !PCI_MSI
1052 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001053 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001054 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001055 A local APIC (Advanced Programmable Interrupt Controller) is an
1056 integrated interrupt controller in the CPU. If you have a single-CPU
1057 system which has a processor with a local APIC, you can say Y here to
1058 enable and use it. If you say Y here even though your machine doesn't
1059 have a local APIC, then the kernel will still run with no slowdown at
1060 all. The local APIC supports CPU-generated self-interrupts (timer,
1061 performance counters), and the NMI watchdog which detects hard
1062 lockups.
1063
1064config X86_UP_IOAPIC
1065 bool "IO-APIC support on uniprocessors"
1066 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001067 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001068 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1069 SMP-capable replacement for PC-style interrupt controllers. Most
1070 SMP systems and many recent uniprocessor systems have one.
1071
1072 If you have a single-CPU system with an IO-APIC, you can say Y here
1073 to use it. If you say Y here even though your machine doesn't have
1074 an IO-APIC, then the kernel will still run with no slowdown at all.
1075
1076config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001077 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001078 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001079 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001080 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001081
1082config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001083 def_bool y
1084 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001085
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001086config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1087 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001088 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001089 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001090 This option enables a workaround that fixes a source of
1091 spurious interrupts. This is recommended when threaded
1092 interrupt handling is used on systems where the generation of
1093 superfluous "boot interrupts" cannot be disabled.
1094
1095 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1096 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1097 kernel does during interrupt handling). On chipsets where this
1098 boot IRQ generation cannot be disabled, this workaround keeps
1099 the original IRQ line masked so that only the equivalent "boot
1100 IRQ" is delivered to the CPUs. The workaround also tells the
1101 kernel to set up the IRQ handler on the boot IRQ line. In this
1102 way only one interrupt is delivered to the kernel. Otherwise
1103 the spurious second interrupt may cause the kernel to bring
1104 down (vital) interrupt lines.
1105
1106 Only affects "broken" chipsets. Interrupt sharing may be
1107 increased on these systems.
1108
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001109config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001110 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001111 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001112 default y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001113 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +02001114 Machine Check support allows the processor to notify the
1115 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001116 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001117 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001118
Tony Luck5de97c92017-03-27 11:33:03 +02001119config X86_MCELOG_LEGACY
1120 bool "Support for deprecated /dev/mcelog character device"
1121 depends on X86_MCE
1122 ---help---
1123 Enable support for /dev/mcelog which is needed by the old mcelog
1124 userspace logging daemon. Consider switching to the new generation
1125 rasdaemon solution.
1126
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001127config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001128 def_bool y
1129 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001130 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001131 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001132 Additional support for intel specific MCE features such as
1133 the thermal monitor.
1134
1135config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001136 def_bool y
1137 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001138 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001139 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001140 Additional support for AMD specific MCE features such as
1141 the DRAM Error Threshold.
1142
Andi Kleen4efc0672009-04-28 19:07:31 +02001143config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001144 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001145 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001146 ---help---
1147 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001148 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001149 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001150
Andi Kleenb2762682009-02-12 13:49:31 +01001151config X86_MCE_THRESHOLD
1152 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001153 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001154
Andi Kleenea149b32009-04-29 19:31:00 +02001155config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001156 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001157 tristate "Machine check injector support"
1158 ---help---
1159 Provide support for injecting machine checks for testing purposes.
1160 If you don't know what a machine check is and you don't do kernel
1161 QA it is safe to say n.
1162
Andi Kleen4efc0672009-04-28 19:07:31 +02001163config X86_THERMAL_VECTOR
1164 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001165 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001166
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001167source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001168
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001169config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001170 bool "Legacy VM86 support"
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001171 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001172 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001173 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001174 This option allows user programs to put the CPU into V8086
1175 mode, which is an 80286-era approximation of 16-bit real mode.
1176
1177 Some very old versions of X and/or vbetool require this option
1178 for user mode setting. Similarly, DOSEMU will use it if
1179 available to accelerate real mode DOS programs. However, any
1180 recent version of DOSEMU, X, or vbetool should be fully
1181 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001182 fall back to software emulation. Nevertheless, if you are using
1183 a 16-bit DOS program where 16-bit performance matters, vm86
1184 mode might be faster than emulation and you might want to
1185 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001186
Ingo Molnar1e642812015-09-05 08:58:10 +02001187 Note that any app that works on a 64-bit kernel is unlikely to
1188 need this option, as 64-bit kernels don't, and can't, support
1189 V8086 mode. This option is also unrelated to 16-bit protected
1190 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001191
Ingo Molnar1e642812015-09-05 08:58:10 +02001192 Enabling this option increases the complexity of the kernel
1193 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001194
Ingo Molnar1e642812015-09-05 08:58:10 +02001195 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001196
1197config VM86
1198 bool
1199 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001200
1201config X86_16BIT
1202 bool "Enable support for 16-bit segments" if EXPERT
1203 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001204 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001205 ---help---
1206 This option is required by programs like Wine to run 16-bit
1207 protected mode legacy code on x86 processors. Disabling
1208 this option saves about 300 bytes on i386, or around 6K text
1209 plus 16K runtime memory on x86-64,
1210
1211config X86_ESPFIX32
1212 def_bool y
1213 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001214
H. Peter Anvin197725d2014-05-04 10:00:49 -07001215config X86_ESPFIX64
1216 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001217 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001218
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001219config X86_VSYSCALL_EMULATION
1220 bool "Enable vsyscall emulation" if EXPERT
1221 default y
1222 depends on X86_64
1223 ---help---
1224 This enables emulation of the legacy vsyscall page. Disabling
1225 it is roughly equivalent to booting with vsyscall=none, except
1226 that it will also disable the helpful warning if a program
1227 tries to use a vsyscall. With this option set to N, offending
1228 programs will just segfault, citing addresses of the form
1229 0xffffffffff600?00.
1230
1231 This option is required by many programs built before 2013, and
1232 care should be used even with newer programs if set to N.
1233
1234 Disabling this option saves about 7K of kernel size and
1235 possibly 4K of additional runtime pagetable memory.
1236
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001237config TOSHIBA
1238 tristate "Toshiba Laptop support"
1239 depends on X86_32
1240 ---help---
1241 This adds a driver to safely access the System Management Mode of
1242 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1243 not work on models with a Phoenix BIOS. The System Management Mode
1244 is used to set the BIOS and power saving options on Toshiba portables.
1245
1246 For information on utilities to make use of this driver see the
1247 Toshiba Linux utilities web site at:
1248 <http://www.buzzard.org.uk/toshiba/>.
1249
1250 Say Y if you intend to run this kernel on a Toshiba portable.
1251 Say N otherwise.
1252
1253config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001254 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001255 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001256 select SENSORS_DELL_SMM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001257 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001258 This option enables legacy /proc/i8k userspace interface in hwmon
1259 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1260 temperature and allows controlling fan speeds of Dell laptops via
1261 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1262 it reports also power and hotkey status. For fan speed control is
1263 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001264
Pali Rohár039ae582015-05-14 13:16:37 +02001265 Say Y if you intend to run this kernel on old Dell laptops or want to
1266 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001267 Say N otherwise.
1268
1269config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001270 bool "Enable X86 board specific fixups for reboot"
1271 depends on X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001272 ---help---
1273 This enables chipset and/or board specific fixups to be done
1274 in order to get reboot to work correctly. This is only needed on
1275 some combinations of hardware and BIOS. The symptom, for which
1276 this config is intended, is when reboot ends with a stalled/hung
1277 system.
1278
1279 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001280 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001281
1282 Say Y if you want to enable the fixup. Currently, it's safe to
1283 enable this option even if you don't need it.
1284 Say N otherwise.
1285
1286config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001287 bool "CPU microcode loading support"
1288 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001289 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001290 select FW_LOADER
1291 ---help---
1292 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001293 Intel and AMD processors. The Intel support is for the IA32 family,
1294 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1295 AMD support is for families 0x10 and later. You will obviously need
1296 the actual microcode binary data itself which is not shipped with
1297 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001298
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001299 The preferred method to load microcode from a detached initrd is described
Jaak Ristioja1897a962018-02-09 11:22:16 +02001300 in Documentation/x86/microcode.txt. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001301 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1302 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001303
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001304 In addition, you can build the microcode into the kernel. For that you
1305 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1306 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001307
Peter Oruba8d86f392008-07-28 18:44:21 +02001308config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001309 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001310 depends on MICROCODE
1311 default MICROCODE
1312 select FW_LOADER
1313 ---help---
1314 This options enables microcode patch loading support for Intel
1315 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001316
Alanb8989db2014-01-20 18:01:56 +00001317 For the current Intel microcode data package go to
1318 <https://downloadcenter.intel.com> and search for
1319 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001320
Peter Oruba80cc9f12008-07-28 18:44:22 +02001321config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001322 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001323 depends on MICROCODE
1324 select FW_LOADER
1325 ---help---
1326 If you select this option, microcode patch loading support for AMD
1327 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001328
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001329config MICROCODE_OLD_INTERFACE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001330 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001331 depends on MICROCODE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001332
1333config X86_MSR
1334 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001335 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001336 This device gives privileged processes access to the x86
1337 Model-Specific Registers (MSRs). It is a character device with
1338 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1339 MSR accesses are directed to a specific CPU on multi-processor
1340 systems.
1341
1342config X86_CPUID
1343 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001344 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001345 This device gives processes access to the x86 CPUID instruction to
1346 be executed on a specific processor. It is a character device
1347 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1348 /dev/cpu/31/cpuid.
1349
1350choice
1351 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001352 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001353 depends on X86_32
1354
1355config NOHIGHMEM
1356 bool "off"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001357 ---help---
1358 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1359 However, the address space of 32-bit x86 processors is only 4
1360 Gigabytes large. That means that, if you have a large amount of
1361 physical memory, not all of it can be "permanently mapped" by the
1362 kernel. The physical memory that's not permanently mapped is called
1363 "high memory".
1364
1365 If you are compiling a kernel which will never run on a machine with
1366 more than 1 Gigabyte total physical RAM, answer "off" here (default
1367 choice and suitable for most users). This will result in a "3GB/1GB"
1368 split: 3GB are mapped so that each process sees a 3GB virtual memory
1369 space and the remaining part of the 4GB virtual memory space is used
1370 by the kernel to permanently map as much physical memory as
1371 possible.
1372
1373 If the machine has between 1 and 4 Gigabytes physical RAM, then
1374 answer "4GB" here.
1375
1376 If more than 4 Gigabytes is used then answer "64GB" here. This
1377 selection turns Intel PAE (Physical Address Extension) mode on.
1378 PAE implements 3-level paging on IA32 processors. PAE is fully
1379 supported by Linux, PAE mode is implemented on all recent Intel
1380 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1381 then the kernel will not boot on CPUs that don't support PAE!
1382
1383 The actual amount of total physical memory will either be
1384 auto detected or can be forced by using a kernel command line option
1385 such as "mem=256M". (Try "man bootparam" or see the documentation of
1386 your boot loader (lilo or loadlin) about how to pass options to the
1387 kernel at boot time.)
1388
1389 If unsure, say "off".
1390
1391config HIGHMEM4G
1392 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001393 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001394 Select this if you have a 32-bit processor and between 1 and 4
1395 gigabytes of physical RAM.
1396
1397config HIGHMEM64G
1398 bool "64GB"
Matthew Whitehead69b8d3f2018-02-15 11:54:55 -05001399 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001400 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001401 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001402 Select this if you have a 32-bit processor and more than 4
1403 gigabytes of physical RAM.
1404
1405endchoice
1406
1407choice
David Rientjes6a108a12011-01-20 14:44:16 -08001408 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001409 default VMSPLIT_3G
1410 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001411 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001412 Select the desired split between kernel and user memory.
1413
1414 If the address range available to the kernel is less than the
1415 physical memory installed, the remaining memory will be available
1416 as "high memory". Accessing high memory is a little more costly
1417 than low memory, as it needs to be mapped into the kernel first.
1418 Note that increasing the kernel address space limits the range
1419 available to user programs, making the address space there
1420 tighter. Selecting anything other than the default 3G/1G split
1421 will also likely make your kernel incompatible with binary-only
1422 kernel modules.
1423
1424 If you are not absolutely sure what you are doing, leave this
1425 option alone!
1426
1427 config VMSPLIT_3G
1428 bool "3G/1G user/kernel split"
1429 config VMSPLIT_3G_OPT
1430 depends on !X86_PAE
1431 bool "3G/1G user/kernel split (for full 1G low memory)"
1432 config VMSPLIT_2G
1433 bool "2G/2G user/kernel split"
1434 config VMSPLIT_2G_OPT
1435 depends on !X86_PAE
1436 bool "2G/2G user/kernel split (for full 2G low memory)"
1437 config VMSPLIT_1G
1438 bool "1G/3G user/kernel split"
1439endchoice
1440
1441config PAGE_OFFSET
1442 hex
1443 default 0xB0000000 if VMSPLIT_3G_OPT
1444 default 0x80000000 if VMSPLIT_2G
1445 default 0x78000000 if VMSPLIT_2G_OPT
1446 default 0x40000000 if VMSPLIT_1G
1447 default 0xC0000000
1448 depends on X86_32
1449
1450config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001451 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001452 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001453
1454config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001455 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001456 depends on X86_32 && !HIGHMEM4G
Christian Melki9d99c712015-10-05 17:31:33 +02001457 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001458 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001459 PAE is required for NX support, and furthermore enables
1460 larger swapspace support for non-overcommit purposes. It
1461 has the cost of more pagetable lookup overhead, and also
1462 consumes more pagetable space per process.
1463
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001464config X86_5LEVEL
1465 bool "Enable 5-level page tables support"
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001466 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001467 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001468 depends on X86_64
1469 ---help---
1470 5-level paging enables access to larger address space:
1471 upto 128 PiB of virtual address space and 4 PiB of
1472 physical address space.
1473
1474 It will be supported by future Intel CPUs.
1475
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001476 A kernel with the option enabled can be booted on machines that
1477 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001478
1479 See Documentation/x86/x86_64/5level-paging.txt for more
1480 information.
1481
1482 Say N if unsure.
1483
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001484config ARCH_PHYS_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001485 def_bool y
1486 depends on X86_64 || X86_PAE
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001487
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001488config ARCH_DMA_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001489 def_bool y
1490 depends on X86_64 || HIGHMEM64G
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001491
Ingo Molnar10971ab2015-03-05 08:18:23 +01001492config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001493 def_bool y
Levin, Alexander (Sasha Levin)4675ff02017-11-15 17:36:02 -08001494 depends on X86_64 && !DEBUG_PAGEALLOC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001495 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001496 Certain kernel features effectively disable kernel
1497 linear 1 GB mappings (even if the CPU otherwise
1498 supports them), so don't confuse the user by printing
1499 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001500
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001501config ARCH_HAS_MEM_ENCRYPT
1502 def_bool y
1503
1504config AMD_MEM_ENCRYPT
1505 bool "AMD Secure Memory Encryption (SME) support"
1506 depends on X86_64 && CPU_SUP_AMD
1507 ---help---
1508 Say yes to enable support for the encryption of system memory.
1509 This requires an AMD processor that supports Secure Memory
1510 Encryption (SME).
1511
1512config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1513 bool "Activate AMD Secure Memory Encryption (SME) by default"
1514 default y
1515 depends on AMD_MEM_ENCRYPT
1516 ---help---
1517 Say yes to have system memory encrypted by default if running on
1518 an AMD processor that supports Secure Memory Encryption (SME).
1519
1520 If set to Y, then the encryption of system memory can be
1521 deactivated with the mem_encrypt=off command line option.
1522
1523 If set to N, then the encryption of system memory can be
1524 activated with the mem_encrypt=on command line option.
1525
Tom Lendackyf88a68f2017-07-17 16:10:09 -05001526config ARCH_USE_MEMREMAP_PROT
1527 def_bool y
1528 depends on AMD_MEM_ENCRYPT
1529
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001530# Common NUMA Features
1531config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001532 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001533 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001534 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1535 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001536 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001537 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001538
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001539 The kernel will try to allocate memory used by a CPU on the
1540 local memory controller of the CPU and add some more
1541 NUMA awareness to the kernel.
1542
Ingo Molnarc280ea52008-11-08 13:29:45 +01001543 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001544 (or later), AMD Opteron, or EM64T NUMA.
1545
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001546 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001547 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001548
1549 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001550
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001551config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001552 def_bool y
1553 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001554 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001555 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001556 Enable AMD NUMA node topology detection. You should say Y here if
1557 you have a multi processor AMD system. This uses an old method to
1558 read the NUMA configuration directly from the builtin Northbridge
1559 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1560 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001561
1562config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001563 def_bool y
1564 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001565 depends on X86_64 && NUMA && ACPI && PCI
1566 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001567 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001568 Enable ACPI SRAT based node topology detection.
1569
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001570# Some NUMA nodes have memory ranges that span
1571# other nodes. Even though a pfn is valid and
1572# between a node's start and end pfns, it may not
1573# reside on that node. See memmap_init_zone()
1574# for details.
1575config NODES_SPAN_OTHER_NODES
1576 def_bool y
1577 depends on X86_64_ACPI_NUMA
1578
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001579config NUMA_EMU
1580 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001581 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001582 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001583 Enable NUMA emulation. A flat machine will be split
1584 into virtual nodes when booted with "numa=fake=N", where N is the
1585 number of nodes. This is only useful for debugging.
1586
1587config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001588 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001589 range 1 10
1590 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001591 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001592 default "3"
1593 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001594 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001595 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001596 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001597
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001598config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001599 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001600 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001601
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001602config ARCH_FLATMEM_ENABLE
1603 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001604 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001605
1606config ARCH_DISCONTIGMEM_ENABLE
1607 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001608 depends on NUMA && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001609
1610config ARCH_DISCONTIGMEM_DEFAULT
1611 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001612 depends on NUMA && X86_32
1613
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001614config ARCH_SPARSEMEM_ENABLE
1615 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001616 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001617 select SPARSEMEM_STATIC if X86_32
1618 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1619
Tejun Heo3b166512011-04-01 11:15:12 +02001620config ARCH_SPARSEMEM_DEFAULT
1621 def_bool y
1622 depends on X86_64
1623
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001624config ARCH_SELECT_MEMORY_MODEL
1625 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001626 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001627
1628config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001629 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001630 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001631 help
1632 This option enables a sysfs memory/probe interface for testing.
1633 See Documentation/memory-hotplug.txt for more information.
1634 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001635
Tejun Heo3b166512011-04-01 11:15:12 +02001636config ARCH_PROC_KCORE_TEXT
1637 def_bool y
1638 depends on X86_64 && PROC_KCORE
1639
Avi Kivitya29815a2010-01-10 16:28:09 +02001640config ILLEGAL_POINTER_VALUE
1641 hex
1642 default 0 if X86_32
1643 default 0xdead000000000000 if X86_64
1644
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001645source "mm/Kconfig"
1646
Dan Williams7a678322015-08-19 00:34:34 -04001647config X86_PMEM_LEGACY_DEVICE
1648 bool
1649
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001650config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001651 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001652 depends on PHYS_ADDR_T_64BIT
1653 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001654 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001655 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001656 help
1657 Treat memory marked using the non-standard e820 type of 12 as used
1658 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1659 The kernel will offer these regions to the 'pmem' driver so
1660 they can be used for persistent storage.
1661
1662 Say Y if unsure.
1663
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001664config HIGHPTE
1665 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001666 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001667 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001668 The VM uses one page table entry for each page of physical memory.
1669 For systems with a lot of RAM, this can be wasteful of precious
1670 low memory. Setting this option will put user-space page table
1671 entries in high memory.
1672
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001673config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001674 bool "Check for low memory corruption"
1675 ---help---
1676 Periodically check for memory corruption in low memory, which
1677 is suspected to be caused by BIOS. Even when enabled in the
1678 configuration, it is disabled at runtime. Enable it by
1679 setting "memory_corruption_check=1" on the kernel command
1680 line. By default it scans the low 64k of memory every 60
1681 seconds; see the memory_corruption_check_size and
1682 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001683 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001684
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001685 When enabled with the default parameters, this option has
1686 almost no overhead, as it reserves a relatively small amount
1687 of memory and scans it infrequently. It both detects corruption
1688 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001689
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001690 It is, however, intended as a diagnostic tool; if repeatable
1691 BIOS-originated corruption always affects the same memory,
1692 you can use memmap= to prevent the kernel from using that
1693 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001694
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001695config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001696 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001697 depends on X86_CHECK_BIOS_CORRUPTION
1698 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001699 ---help---
1700 Set whether the default state of memory_corruption_check is
1701 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001702
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001703config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001704 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1705 default 64
1706 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001707 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001708 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001709
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001710 The first page contains BIOS data structures that the kernel
1711 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001712
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001713 By default we reserve the first 64K of physical RAM, as a
1714 number of BIOSes are known to corrupt that memory range
1715 during events such as suspend/resume or monitor cable
1716 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001717
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001718 You can set this to 4 if you are absolutely sure that you
1719 trust the BIOS to get all its memory reservations and usages
1720 right. If you know your BIOS have problems beyond the
1721 default 64K area, you can set this to 640 to avoid using the
1722 entire low memory range.
1723
1724 If you have doubts about the BIOS (e.g. suspend/resume does
1725 not work or there's kernel crashes after certain hardware
1726 hotplug events) then you might want to enable
1727 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1728 typical corruption patterns.
1729
1730 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001731
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001732config MATH_EMULATION
1733 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001734 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001735 prompt "Math emulation" if X86_32
1736 ---help---
1737 Linux can emulate a math coprocessor (used for floating point
1738 operations) if you don't have one. 486DX and Pentium processors have
1739 a math coprocessor built in, 486SX and 386 do not, unless you added
1740 a 487DX or 387, respectively. (The messages during boot time can
1741 give you some hints here ["man dmesg"].) Everyone needs either a
1742 coprocessor or this emulation.
1743
1744 If you don't have a math coprocessor, you need to say Y here; if you
1745 say Y here even though you have a coprocessor, the coprocessor will
1746 be used nevertheless. (This behavior can be changed with the kernel
1747 command line option "no387", which comes handy if your coprocessor
1748 is broken. Try "man bootparam" or see the documentation of your boot
1749 loader (lilo or loadlin) about how to pass options to the kernel at
1750 boot time.) This means that it is a good idea to say Y here if you
1751 intend to use this kernel on different machines.
1752
1753 More information about the internals of the Linux math coprocessor
1754 emulation can be found in <file:arch/x86/math-emu/README>.
1755
1756 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1757 kernel, it won't hurt.
1758
1759config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001760 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001761 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001762 ---help---
1763 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1764 the Memory Type Range Registers (MTRRs) may be used to control
1765 processor access to memory ranges. This is most useful if you have
1766 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1767 allows bus write transfers to be combined into a larger transfer
1768 before bursting over the PCI/AGP bus. This can increase performance
1769 of image write operations 2.5 times or more. Saying Y here creates a
1770 /proc/mtrr file which may be used to manipulate your processor's
1771 MTRRs. Typically the X server should use this.
1772
1773 This code has a reasonably generic interface so that similar
1774 control registers on other processors can be easily supported
1775 as well:
1776
1777 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1778 Registers (ARRs) which provide a similar functionality to MTRRs. For
1779 these, the ARRs are used to emulate the MTRRs.
1780 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1781 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1782 write-combining. All of these processors are supported by this code
1783 and it makes sense to say Y here if you have one of them.
1784
1785 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1786 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1787 can lead to all sorts of problems, so it's good to say Y here.
1788
1789 You can safely say Y even if your machine doesn't have MTRRs, you'll
1790 just add about 9 KB to your kernel.
1791
Randy Dunlap7225e752008-07-26 17:54:22 -07001792 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001793
Yinghai Lu95ffa242008-04-29 03:52:33 -07001794config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001795 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001796 prompt "MTRR cleanup support"
1797 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001798 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001799 Convert MTRR layout from continuous to discrete, so X drivers can
1800 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001801
Thomas Gleixneraba37282008-07-15 14:48:48 +02001802 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001803 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001804 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001805
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001806 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001807
1808config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001809 int "MTRR cleanup enable value (0-1)"
1810 range 0 1
1811 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001812 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001813 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001814 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001815
Yinghai Lu12031a62008-05-02 02:40:22 -07001816config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1817 int "MTRR cleanup spare reg num (0-7)"
1818 range 0 7
1819 default "1"
1820 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001821 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001822 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001823 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001824
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001825config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001826 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001827 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001828 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001829 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001830 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001831
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001832 PATs are the modern equivalents of MTRRs and are much more
1833 flexible than MTRRs.
1834
1835 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001836 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001837
1838 If unsure, say Y.
1839
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001840config ARCH_USES_PG_UNCACHED
1841 def_bool y
1842 depends on X86_PAT
1843
H. Peter Anvin628c6242011-07-31 13:59:29 -07001844config ARCH_RANDOM
1845 def_bool y
1846 prompt "x86 architectural random number generator" if EXPERT
1847 ---help---
1848 Enable the x86 architectural RDRAND instruction
1849 (Intel Bull Mountain technology) to generate random numbers.
1850 If supported, this is a high bandwidth, cryptographically
1851 secure hardware random number generator.
1852
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001853config X86_SMAP
1854 def_bool y
1855 prompt "Supervisor Mode Access Prevention" if EXPERT
1856 ---help---
1857 Supervisor Mode Access Prevention (SMAP) is a security
1858 feature in newer Intel processors. There is a small
1859 performance cost if this enabled and turned on; there is
1860 also a small increase in the kernel size if this is enabled.
1861
1862 If unsure, say Y.
1863
Ricardo Neriaa35f892017-11-05 18:27:54 -08001864config X86_INTEL_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001865 def_bool y
Ricardo Neriaa35f892017-11-05 18:27:54 -08001866 depends on CPU_SUP_INTEL
1867 prompt "Intel User Mode Instruction Prevention" if EXPERT
1868 ---help---
1869 The User Mode Instruction Prevention (UMIP) is a security
1870 feature in newer Intel processors. If enabled, a general
Ricardo Neri796ebc82017-11-13 22:29:42 -08001871 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1872 or STR instructions are executed in user mode. These instructions
1873 unnecessarily expose information about the hardware state.
1874
1875 The vast majority of applications do not use these instructions.
1876 For the very few that do, software emulation is provided in
1877 specific cases in protected and virtual-8086 modes. Emulated
1878 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001879
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001880config X86_INTEL_MPX
1881 prompt "Intel MPX (Memory Protection Extensions)"
1882 def_bool n
Rik van Rieldf3735c2017-09-06 16:25:11 -07001883 # Note: only available in 64-bit mode due to VMA flags shortage
1884 depends on CPU_SUP_INTEL && X86_64
1885 select ARCH_USES_HIGH_VMA_FLAGS
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001886 ---help---
1887 MPX provides hardware features that can be used in
1888 conjunction with compiler-instrumented code to check
1889 memory references. It is designed to detect buffer
1890 overflow or underflow bugs.
1891
1892 This option enables running applications which are
1893 instrumented or otherwise use MPX. It does not use MPX
1894 itself inside the kernel or to protect the kernel
1895 against bad memory references.
1896
1897 Enabling this option will make the kernel larger:
1898 ~8k of kernel text and 36 bytes of data on a 64-bit
1899 defconfig. It adds a long to the 'mm_struct' which
1900 will increase the kernel memory overhead of each
1901 process and adds some branches to paths used during
1902 exec() and munmap().
1903
1904 For details, see Documentation/x86/intel_mpx.txt
1905
1906 If unsure, say N.
1907
Dave Hansen35e97792016-02-12 13:02:00 -08001908config X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001909 prompt "Intel Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001910 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001911 # Note: only available in 64-bit mode
Dave Hansen35e97792016-02-12 13:02:00 -08001912 depends on CPU_SUP_INTEL && X86_64
Ingo Molnar52c8e602016-11-15 10:15:03 +01001913 select ARCH_USES_HIGH_VMA_FLAGS
1914 select ARCH_HAS_PKEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001915 ---help---
1916 Memory Protection Keys provides a mechanism for enforcing
1917 page-based protections, but without requiring modification of the
1918 page tables when an application changes protection domains.
1919
1920 For details, see Documentation/x86/protection-keys.txt
1921
1922 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001923
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001924config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001925 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001926 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001927 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001928 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001929 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001930 This enables the kernel to use EFI runtime services that are
1931 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001932
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001933 This option is only useful on systems that have EFI firmware.
1934 In addition, you should use the latest ELILO loader available
1935 at <http://elilo.sourceforge.net> in order to take advantage
1936 of EFI runtime services. However, even with this option, the
1937 resultant kernel should continue to boot on existing non-EFI
1938 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001939
Matt Fleming291f3632011-12-12 21:27:52 +00001940config EFI_STUB
1941 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001942 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001943 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001944 ---help---
1945 This kernel feature allows a bzImage to be loaded directly
1946 by EFI firmware without the use of a bootloader.
1947
Roy Franz4172fe22013-09-22 15:45:25 -07001948 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001949
Matt Fleming7d453ee2014-01-10 18:52:06 +00001950config EFI_MIXED
1951 bool "EFI mixed-mode support"
1952 depends on EFI_STUB && X86_64
1953 ---help---
1954 Enabling this feature allows a 64-bit kernel to be booted
1955 on a 32-bit firmware, provided that your CPU supports 64-bit
1956 mode.
1957
1958 Note that it is not possible to boot a mixed-mode enabled
1959 kernel via the EFI boot stub - a bootloader that supports
1960 the EFI handover protocol must be used.
1961
1962 If unsure, say N.
1963
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001964config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001965 def_bool y
1966 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001967 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001968 This kernel feature is useful for number crunching applications
1969 that may need to compute untrusted bytecode during their
1970 execution. By using pipes or other transports made available to
1971 the process as file descriptors supporting the read/write
1972 syscalls, it's possible to isolate those applications in
1973 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001974 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001975 and the task is only allowed to execute a few safe syscalls
1976 defined by each seccomp mode.
1977
1978 If unsure, say Y. Only embedded should say N here.
1979
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001980source kernel/Kconfig.hz
1981
1982config KEXEC
1983 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001984 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001985 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001986 kexec is a system call that implements the ability to shutdown your
1987 current kernel, and to start another kernel. It is like a reboot
1988 but it is independent of the system firmware. And like a reboot
1989 you can start any kernel with it, not just Linux.
1990
1991 The name comes from the similarity to the exec system call.
1992
1993 It is an ongoing process to be certain the hardware in a machine
1994 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001995 initially work for you. As of this writing the exact hardware
1996 interface is strongly in flux, so no good recommendation can be
1997 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001998
Vivek Goyal74ca3172014-08-29 15:18:46 -07001999config KEXEC_FILE
2000 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07002001 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07002002 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07002003 depends on X86_64
2004 depends on CRYPTO=y
2005 depends on CRYPTO_SHA256=y
2006 ---help---
2007 This is new version of kexec system call. This system call is
2008 file based and takes file descriptors as system call argument
2009 for kernel and initramfs as opposed to list of segments as
2010 accepted by previous system call.
2011
AKASHI Takahirob799a092018-04-13 15:35:45 -07002012config ARCH_HAS_KEXEC_PURGATORY
2013 def_bool KEXEC_FILE
2014
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002015config KEXEC_VERIFY_SIG
2016 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07002017 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002018 ---help---
2019 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002020 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002021
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002022 In addition to that option, you need to enable signature
2023 verification for the corresponding kernel image type being
2024 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002025
2026config KEXEC_BZIMAGE_VERIFY_SIG
2027 bool "Enable bzImage signature verification support"
2028 depends on KEXEC_VERIFY_SIG
2029 depends on SIGNED_PE_FILE_VERIFICATION
2030 select SYSTEM_TRUSTED_KEYRING
2031 ---help---
2032 Enable bzImage signature verification support.
2033
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002034config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002035 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002036 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002037 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002038 Generate crash dump after being started by kexec.
2039 This should be normally only set in special crash dump kernels
2040 which are loaded in the main kernel with kexec-tools into
2041 a specially reserved region and then later executed after
2042 a crash by kdump/kexec. The crash dump kernel must be compiled
2043 to a memory address not used by the main kernel or BIOS using
2044 PHYSICAL_START, or it must be built as a relocatable image
2045 (CONFIG_RELOCATABLE=y).
2046 For more details see Documentation/kdump/kdump.txt
2047
Huang Ying3ab83522008-07-25 19:45:07 -07002048config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002049 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002050 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002051 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07002052 Jump between original kernel and kexeced kernel and invoke
2053 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002054
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002055config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002056 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002057 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002058 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002059 This gives the physical address where the kernel is loaded.
2060
2061 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2062 bzImage will decompress itself to above physical address and
2063 run from there. Otherwise, bzImage will run from the address where
2064 it has been loaded by the boot loader and will ignore above physical
2065 address.
2066
2067 In normal kdump cases one does not have to set/change this option
2068 as now bzImage can be compiled as a completely relocatable image
2069 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2070 address. This option is mainly useful for the folks who don't want
2071 to use a bzImage for capturing the crash dump and want to use a
2072 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2073 to be specifically compiled to run from a specific memory area
2074 (normally a reserved region) and this option comes handy.
2075
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002076 So if you are using bzImage for capturing the crash dump,
2077 leave the value here unchanged to 0x1000000 and set
2078 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2079 for capturing the crash dump change this value to start of
2080 the reserved region. In other words, it can be set based on
2081 the "X" value as specified in the "crashkernel=YM@XM"
2082 command line boot parameter passed to the panic-ed
2083 kernel. Please take a look at Documentation/kdump/kdump.txt
2084 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002085
2086 Usage of bzImage for capturing the crash dump is recommended as
2087 one does not have to build two kernels. Same kernel can be used
2088 as production kernel and capture kernel. Above option should have
2089 gone away after relocatable bzImage support is introduced. But it
2090 is present because there are users out there who continue to use
2091 vmlinux for dump capture. This option should go away down the
2092 line.
2093
2094 Don't change this unless you know what you are doing.
2095
2096config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002097 bool "Build a relocatable kernel"
2098 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002099 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002100 This builds a kernel image that retains relocation information
2101 so it can be loaded someplace besides the default 1MB.
2102 The relocations tend to make the kernel binary about 10% larger,
2103 but are discarded at runtime.
2104
2105 One use is for the kexec on panic case where the recovery kernel
2106 must live at a different physical address than the primary
2107 kernel.
2108
2109 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2110 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002111 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002112
Kees Cook8ab38202013-10-10 17:18:14 -07002113config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002114 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002115 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002116 default y
Kees Cook8ab38202013-10-10 17:18:14 -07002117 ---help---
Baoquan Hee8581e32016-04-20 13:55:43 -07002118 In support of Kernel Address Space Layout Randomization (KASLR),
2119 this randomizes the physical address at which the kernel image
2120 is decompressed and the virtual address where the kernel
2121 image is mapped, as a security feature that deters exploit
2122 attempts relying on knowledge of the location of kernel
2123 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002124
Kees Cooked9f0072016-05-25 15:45:33 -07002125 On 64-bit, the kernel physical and virtual addresses are
2126 randomized separately. The physical address will be anywhere
2127 between 16MB and the top of physical memory (up to 64TB). The
2128 virtual address will be randomized from 16MB up to 1GB (9 bits
2129 of entropy). Note that this also reduces the memory space
2130 available to kernel modules from 1.5GB to 1GB.
2131
2132 On 32-bit, the kernel physical and virtual addresses are
2133 randomized together. They will be randomized from 16MB up to
2134 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002135
Baoquan Hee8581e32016-04-20 13:55:43 -07002136 Entropy is generated using the RDRAND instruction if it is
2137 supported. If RDTSC is supported, its value is mixed into
2138 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002139 supported, then entropy is read from the i8254 timer. The
2140 usable entropy is limited by the kernel being built using
2141 2GB addressing, and that PHYSICAL_ALIGN must be at a
2142 minimum of 2MB. As a result, only 10 bits of entropy are
2143 theoretically possible, but the implementations are further
2144 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002145
Ingo Molnar6807c842017-04-18 11:08:12 +02002146 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002147
2148# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002149config X86_NEED_RELOCS
2150 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002151 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002152
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002153config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002154 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002155 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002156 range 0x2000 0x1000000 if X86_32
2157 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002158 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002159 This value puts the alignment restrictions on physical address
2160 where kernel is loaded and run from. Kernel is compiled for an
2161 address which meets above alignment restriction.
2162
2163 If bootloader loads the kernel at a non-aligned address and
2164 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2165 address aligned to above value and run from there.
2166
2167 If bootloader loads the kernel at a non-aligned address and
2168 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2169 load address and decompress itself to the address it has been
2170 compiled for and run from there. The address for which kernel is
2171 compiled already meets above alignment restrictions. Hence the
2172 end result is that kernel runs from a physical address meeting
2173 above alignment restrictions.
2174
Kees Cooka0215062013-07-08 09:15:17 -07002175 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2176 this value must be a multiple of 0x200000.
2177
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002178 Don't change this unless you know what you are doing.
2179
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002180config DYNAMIC_MEMORY_LAYOUT
2181 bool
2182 ---help---
2183 This option makes base addresses of vmalloc and vmemmap as well as
2184 __PAGE_OFFSET movable during boot.
2185
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002186config RANDOMIZE_MEMORY
2187 bool "Randomize the kernel memory sections"
2188 depends on X86_64
2189 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002190 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002191 default RANDOMIZE_BASE
2192 ---help---
2193 Randomizes the base virtual address of kernel memory sections
2194 (physical memory mapping, vmalloc & vmemmap). This security feature
2195 makes exploits relying on predictable memory locations less reliable.
2196
2197 The order of allocations remains unchanged. Entropy is generated in
2198 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2199 configuration have in average 30,000 different possible virtual
2200 addresses for each memory section.
2201
Ingo Molnar6807c842017-04-18 11:08:12 +02002202 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002203
Thomas Garnier90397a42016-06-21 17:47:06 -07002204config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2205 hex "Physical memory mapping padding" if EXPERT
2206 depends on RANDOMIZE_MEMORY
2207 default "0xa" if MEMORY_HOTPLUG
2208 default "0x0"
2209 range 0x1 0x40 if MEMORY_HOTPLUG
2210 range 0x0 0x40
2211 ---help---
2212 Define the padding in terabytes added to the existing physical
2213 memory size during kernel memory randomization. It is useful
2214 for memory hotplug support but reduces the entropy available for
2215 address randomization.
2216
2217 If unsure, leave at the default value.
2218
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002219config HOTPLUG_CPU
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002220 bool "Support for hot-pluggable CPUs"
Stephen Rothwell40b31362013-05-21 13:49:35 +10002221 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002222 ---help---
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002223 Say Y here to allow turning CPUs off and on. CPUs can be
2224 controlled through /sys/devices/system/cpu.
2225 ( Note: power management support will enable this option
2226 automatically on SMP systems. )
2227 Say N if you want to disable CPU hotplug.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002228
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002229config BOOTPARAM_HOTPLUG_CPU0
2230 bool "Set default setting of cpu0_hotpluggable"
2231 default n
Kees Cook2c922cd2013-01-22 13:01:19 -08002232 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002233 ---help---
2234 Set whether default state of cpu0_hotpluggable is on or off.
2235
2236 Say Y here to enable CPU0 hotplug by default. If this switch
2237 is turned on, there is no need to give cpu0_hotplug kernel
2238 parameter and the CPU0 hotplug feature is enabled by default.
2239
2240 Please note: there are two known CPU0 dependencies if you want
2241 to enable the CPU0 hotplug feature either by this switch or by
2242 cpu0_hotplug kernel parameter.
2243
2244 First, resume from hibernate or suspend always starts from CPU0.
2245 So hibernate and suspend are prevented if CPU0 is offline.
2246
2247 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2248 offline if any interrupt can not migrate out of CPU0. There may
2249 be other CPU0 dependencies.
2250
2251 Please make sure the dependencies are under your control before
2252 you enable this feature.
2253
2254 Say N if you don't want to enable CPU0 hotplug feature by default.
2255 You still can enable the CPU0 hotplug feature at boot by kernel
2256 parameter cpu0_hotplug.
2257
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002258config DEBUG_HOTPLUG_CPU0
2259 def_bool n
2260 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002261 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002262 ---help---
2263 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2264 soon as possible and boots up userspace with CPU0 offlined. User
2265 can online CPU0 back after boot time.
2266
2267 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2268 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2269 compilation or giving cpu0_hotplug kernel parameter at boot.
2270
2271 If unsure, say N.
2272
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002273config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002274 def_bool n
2275 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002276 depends on COMPAT_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002277 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002278 Certain buggy versions of glibc will crash if they are
2279 presented with a 32-bit vDSO that is not mapped at the address
2280 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002281
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002282 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2283 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2284 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2285 the only released version with the bug, but OpenSUSE 9
2286 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002287
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002288 The symptom of the bug is that everything crashes on startup, saying:
2289 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2290
2291 Saying Y here changes the default value of the vdso32 boot
2292 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2293 This works around the glibc bug but hurts performance.
2294
2295 If unsure, say N: if you are compiling your own kernel, you
2296 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002297
Kees Cook3dc33bd2015-08-12 17:55:19 -07002298choice
2299 prompt "vsyscall table for legacy applications"
2300 depends on X86_64
2301 default LEGACY_VSYSCALL_EMULATE
2302 help
2303 Legacy user code that does not know how to find the vDSO expects
2304 to be able to issue three syscalls by calling fixed addresses in
2305 kernel space. Since this location is not randomized with ASLR,
2306 it can be used to assist security vulnerability exploitation.
2307
2308 This setting can be changed at boot time via the kernel command
Andy Lutomirski076ca272018-03-07 11:12:27 -08002309 line parameter vsyscall=[emulate|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002310
2311 On a system with recent enough glibc (2.14 or newer) and no
2312 static binaries, you can say None without a performance penalty
2313 to improve security.
2314
2315 If unsure, select "Emulate".
2316
Kees Cook3dc33bd2015-08-12 17:55:19 -07002317 config LEGACY_VSYSCALL_EMULATE
2318 bool "Emulate"
2319 help
2320 The kernel traps and emulates calls into the fixed
2321 vsyscall address mapping. This makes the mapping
2322 non-executable, but it still contains known contents,
2323 which could be used in certain rare security vulnerability
2324 exploits. This configuration is recommended when userspace
2325 still uses the vsyscall area.
2326
2327 config LEGACY_VSYSCALL_NONE
2328 bool "None"
2329 help
2330 There will be no vsyscall mapping at all. This will
2331 eliminate any risk of ASLR bypass due to the vsyscall
2332 fixed address mapping. Attempts to use the vsyscalls
2333 will be reported to dmesg, so that either old or
2334 malicious userspace programs can be identified.
2335
2336endchoice
2337
Tim Bird516cbf32008-08-12 12:52:36 -07002338config CMDLINE_BOOL
2339 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002340 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002341 Allow for specifying boot arguments to the kernel at
2342 build time. On some systems (e.g. embedded ones), it is
2343 necessary or convenient to provide some or all of the
2344 kernel boot arguments with the kernel itself (that is,
2345 to not rely on the boot loader to provide them.)
2346
2347 To compile command line arguments into the kernel,
2348 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002349 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002350
2351 Systems with fully functional boot loaders (i.e. non-embedded)
2352 should leave this option set to 'N'.
2353
2354config CMDLINE
2355 string "Built-in kernel command string"
2356 depends on CMDLINE_BOOL
2357 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002358 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002359 Enter arguments here that should be compiled into the kernel
2360 image and used at boot time. If the boot loader provides a
2361 command line at boot time, it is appended to this string to
2362 form the full kernel command line, when the system boots.
2363
2364 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2365 change this behavior.
2366
2367 In most cases, the command line (whether built-in or provided
2368 by the boot loader) should specify the device for the root
2369 file system.
2370
2371config CMDLINE_OVERRIDE
2372 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002373 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002374 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002375 Set this option to 'Y' to have the kernel ignore the boot loader
2376 command line, and use ONLY the built-in command line.
2377
2378 This is used to work around broken boot loaders. This should
2379 be set to 'N' under normal conditions.
2380
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002381config MODIFY_LDT_SYSCALL
2382 bool "Enable the LDT (local descriptor table)" if EXPERT
2383 default y
2384 ---help---
2385 Linux can allow user programs to install a per-process x86
2386 Local Descriptor Table (LDT) using the modify_ldt(2) system
2387 call. This is required to run 16-bit or segmented code such as
2388 DOSEMU or some Wine programs. It is also used by some very old
2389 threading libraries.
2390
2391 Enabling this feature adds a small amount of overhead to
2392 context switches and increases the low-level kernel attack
2393 surface. Disabling it removes the modify_ldt(2) system call.
2394
2395 Saying 'N' here may make sense for embedded or server kernels.
2396
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002397source "kernel/livepatch/Kconfig"
2398
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002399endmenu
2400
Michal Hocko3072e412017-09-08 16:11:39 -07002401config ARCH_HAS_ADD_PAGES
2402 def_bool y
2403 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2404
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002405config ARCH_ENABLE_MEMORY_HOTPLUG
2406 def_bool y
2407 depends on X86_64 || (X86_32 && HIGHMEM)
2408
Gary Hade35551052008-10-31 10:52:03 -07002409config ARCH_ENABLE_MEMORY_HOTREMOVE
2410 def_bool y
2411 depends on MEMORY_HOTPLUG
2412
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002413config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002414 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002415 depends on NUMA
2416
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002417config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2418 def_bool y
2419 depends on X86_64 || X86_PAE
2420
Naoya Horiguchic177c812014-06-04 16:05:35 -07002421config ARCH_ENABLE_HUGEPAGE_MIGRATION
2422 def_bool y
2423 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2424
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002425config ARCH_ENABLE_THP_MIGRATION
2426 def_bool y
2427 depends on X86_64 && TRANSPARENT_HUGEPAGE
2428
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002429menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002430
2431config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002432 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002433 depends on X86_64 && HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002434
2435source "kernel/power/Kconfig"
2436
2437source "drivers/acpi/Kconfig"
2438
Feng Tangefafc8b2009-08-14 15:23:29 -04002439source "drivers/sfi/Kconfig"
2440
Andi Kleena6b68072008-01-30 13:32:49 +01002441config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002442 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002443 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002444
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002445menuconfig APM
2446 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002447 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002448 ---help---
2449 APM is a BIOS specification for saving power using several different
2450 techniques. This is mostly useful for battery powered laptops with
2451 APM compliant BIOSes. If you say Y here, the system time will be
2452 reset after a RESUME operation, the /proc/apm device will provide
2453 battery status information, and user-space programs will receive
2454 notification of APM "events" (e.g. battery status change).
2455
2456 If you select "Y" here, you can disable actual use of the APM
2457 BIOS by passing the "apm=off" option to the kernel at boot time.
2458
2459 Note that the APM support is almost completely disabled for
2460 machines with more than one CPU.
2461
2462 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002463 and more information, read <file:Documentation/power/apm-acpi.txt>
2464 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002465 <http://www.tldp.org/docs.html#howto>.
2466
2467 This driver does not spin down disk drives (see the hdparm(8)
2468 manpage ("man 8 hdparm") for that), and it doesn't turn off
2469 VESA-compliant "green" monitors.
2470
2471 This driver does not support the TI 4000M TravelMate and the ACER
2472 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2473 desktop machines also don't have compliant BIOSes, and this driver
2474 may cause those machines to panic during the boot phase.
2475
2476 Generally, if you don't have a battery in your machine, there isn't
2477 much point in using this driver and you should say N. If you get
2478 random kernel OOPSes or reboots that don't seem to be related to
2479 anything, try disabling/enabling this option (or disabling/enabling
2480 APM in your BIOS).
2481
2482 Some other things you should try when experiencing seemingly random,
2483 "weird" problems:
2484
2485 1) make sure that you have enough swap space and that it is
2486 enabled.
2487 2) pass the "no-hlt" option to the kernel
2488 3) switch on floating point emulation in the kernel and pass
2489 the "no387" option to the kernel
2490 4) pass the "floppy=nodma" option to the kernel
2491 5) pass the "mem=4M" option to the kernel (thereby disabling
2492 all but the first 4 MB of RAM)
2493 6) make sure that the CPU is not over clocked.
2494 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2495 8) disable the cache from your BIOS settings
2496 9) install a fan for the video card or exchange video RAM
2497 10) install a better fan for the CPU
2498 11) exchange RAM chips
2499 12) exchange the motherboard.
2500
2501 To compile this driver as a module, choose M here: the
2502 module will be called apm.
2503
2504if APM
2505
2506config APM_IGNORE_USER_SUSPEND
2507 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002508 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002509 This option will ignore USER SUSPEND requests. On machines with a
2510 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2511 series notebooks, it is necessary to say Y because of a BIOS bug.
2512
2513config APM_DO_ENABLE
2514 bool "Enable PM at boot time"
2515 ---help---
2516 Enable APM features at boot time. From page 36 of the APM BIOS
2517 specification: "When disabled, the APM BIOS does not automatically
2518 power manage devices, enter the Standby State, enter the Suspend
2519 State, or take power saving steps in response to CPU Idle calls."
2520 This driver will make CPU Idle calls when Linux is idle (unless this
2521 feature is turned off -- see "Do CPU IDLE calls", below). This
2522 should always save battery power, but more complicated APM features
2523 will be dependent on your BIOS implementation. You may need to turn
2524 this option off if your computer hangs at boot time when using APM
2525 support, or if it beeps continuously instead of suspending. Turn
2526 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2527 T400CDT. This is off by default since most machines do fine without
2528 this feature.
2529
2530config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002531 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002532 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002533 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002534 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2535 On some machines, this can activate improved power savings, such as
2536 a slowed CPU clock rate, when the machine is idle. These idle calls
2537 are made after the idle loop has run for some length of time (e.g.,
2538 333 mS). On some machines, this will cause a hang at boot time or
2539 whenever the CPU becomes idle. (On machines with more than one CPU,
2540 this option does nothing.)
2541
2542config APM_DISPLAY_BLANK
2543 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002544 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002545 Enable console blanking using the APM. Some laptops can use this to
2546 turn off the LCD backlight when the screen blanker of the Linux
2547 virtual console blanks the screen. Note that this is only used by
2548 the virtual console screen blanker, and won't turn off the backlight
2549 when using the X Window system. This also doesn't have anything to
2550 do with your VESA-compliant power-saving monitor. Further, this
2551 option doesn't work for all laptops -- it might not turn off your
2552 backlight at all, or it might print a lot of errors to the console,
2553 especially if you are using gpm.
2554
2555config APM_ALLOW_INTS
2556 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002557 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002558 Normally we disable external interrupts while we are making calls to
2559 the APM BIOS as a measure to lessen the effects of a badly behaving
2560 BIOS implementation. The BIOS should reenable interrupts if it
2561 needs to. Unfortunately, some BIOSes do not -- especially those in
2562 many of the newer IBM Thinkpads. If you experience hangs when you
2563 suspend, try setting this to Y. Otherwise, say N.
2564
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002565endif # APM
2566
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002567source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002568
2569source "drivers/cpuidle/Kconfig"
2570
Andy Henroid27471fd2008-10-09 11:45:22 -07002571source "drivers/idle/Kconfig"
2572
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002573endmenu
2574
2575
2576menu "Bus options (PCI etc.)"
2577
2578config PCI
Ingo Molnar1ac97012008-05-19 14:10:14 +02002579 bool "PCI support"
Adrian Bunk1c858082008-01-30 13:32:32 +01002580 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002581 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002582 Find out whether you have a PCI motherboard. PCI is the name of a
2583 bus system, i.e. the way the CPU talks to the other stuff inside
2584 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2585 VESA. If you have PCI, say Y, otherwise N.
2586
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002587choice
2588 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002589 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002590 default PCI_GOANY
2591 ---help---
2592 On PCI systems, the BIOS can be used to detect the PCI devices and
2593 determine their configuration. However, some old PCI motherboards
2594 have BIOS bugs and may crash if this is done. Also, some embedded
2595 PCI-based systems don't have any BIOS at all. Linux can also try to
2596 detect the PCI hardware directly without using the BIOS.
2597
2598 With this option, you can specify how Linux should detect the
2599 PCI devices. If you choose "BIOS", the BIOS will be used,
2600 if you choose "Direct", the BIOS won't be used, and if you
2601 choose "MMConfig", then PCI Express MMCONFIG will be used.
2602 If you choose "Any", the kernel will try MMCONFIG, then the
2603 direct access method and falls back to the BIOS if that doesn't
2604 work. If unsure, go with the default, which is "Any".
2605
2606config PCI_GOBIOS
2607 bool "BIOS"
2608
2609config PCI_GOMMCONFIG
2610 bool "MMConfig"
2611
2612config PCI_GODIRECT
2613 bool "Direct"
2614
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002615config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002616 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002617 depends on OLPC
2618
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002619config PCI_GOANY
2620 bool "Any"
2621
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002622endchoice
2623
2624config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002625 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002626 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002627
2628# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2629config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002630 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002631 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002632
2633config PCI_MMCONFIG
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002634 bool "Support mmconfig PCI config space access" if X86_64
2635 default y
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002636 depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002637 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002638
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002639config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002640 def_bool y
2641 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002642
Alex Nixonb5401a92010-03-18 16:31:34 -04002643config PCI_XEN
2644 def_bool y
2645 depends on PCI && XEN
2646 select SWIOTLB_XEN
2647
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002648config PCI_DOMAINS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002649 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002650 depends on PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002651
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002652config MMCONF_FAM10H
2653 def_bool y
2654 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002655
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002656config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002657 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002658 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002659 help
2660 Read the PCI windows out of the CNB20LE host bridge. This allows
2661 PCI hotplug to work on systems with the CNB20LE chipset which do
2662 not have ACPI.
2663
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002664 There's no public spec for this chipset, and this functionality
2665 is known to be incomplete.
2666
2667 You should say N unless you know you need this.
2668
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002669source "drivers/pci/Kconfig"
2670
William Breathitt Gray3a495512016-05-27 18:08:27 -04002671config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002672 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002673 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002674 Expose ISA bus device drivers and options available for selection and
2675 configuration. Enable this option if your target machine has an ISA
2676 bus. ISA is an older system, displaced by PCI and newer bus
2677 architectures -- if your target machine is modern, it probably does
2678 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002679
2680 If unsure, say N.
2681
David Rientjes1c00f012011-03-22 16:34:59 -07002682# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002683config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002684 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2685 default y
2686 help
2687 Enables ISA-style DMA support for devices requiring such controllers.
2688 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002689
Linus Torvalds51e68d02016-05-21 10:25:19 -07002690if X86_32
2691
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002692config ISA
2693 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002694 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002695 Find out whether you have ISA slots on your motherboard. ISA is the
2696 name of a bus system, i.e. the way the CPU talks to the other stuff
2697 inside your box. Other bus systems are PCI, EISA, MicroChannel
2698 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2699 newer boards don't support it. If you have ISA, say Y, otherwise N.
2700
2701config EISA
2702 bool "EISA support"
2703 depends on ISA
2704 ---help---
2705 The Extended Industry Standard Architecture (EISA) bus was
2706 developed as an open alternative to the IBM MicroChannel bus.
2707
2708 The EISA bus provided some of the features of the IBM MicroChannel
2709 bus while maintaining backward compatibility with cards made for
2710 the older ISA bus. The EISA bus saw limited use between 1988 and
2711 1995 when it was made obsolete by the PCI bus.
2712
2713 Say Y here if you are building a kernel for an EISA-based machine.
2714
2715 Otherwise, say N.
2716
2717source "drivers/eisa/Kconfig"
2718
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002719config SCx200
2720 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002721 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002722 This provides basic support for National Semiconductor's
2723 (now AMD's) Geode processors. The driver probes for the
2724 PCI-IDs of several on-chip devices, so its a good dependency
2725 for other scx200_* drivers.
2726
2727 If compiled as a module, the driver is named scx200.
2728
2729config SCx200HR_TIMER
2730 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002731 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002732 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002733 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002734 This driver provides a clocksource built upon the on-chip
2735 27MHz high-resolution timer. Its also a workaround for
2736 NSC Geode SC-1100's buggy TSC, which loses time when the
2737 processor goes idle (as is done by the scheduler). The
2738 other workaround is idle=poll boot option.
2739
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002740config OLPC
2741 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002742 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002743 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002744 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002745 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002746 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002747 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002748 Add support for detecting the unique features of the OLPC
2749 XO hardware.
2750
Daniel Drakea3128582011-06-25 17:34:10 +01002751config OLPC_XO1_PM
2752 bool "OLPC XO-1 Power Management"
Daniel Drake97c4cb72011-06-25 17:34:11 +01002753 depends on OLPC && MFD_CS5535 && PM_SLEEP
Daniel Drakea3128582011-06-25 17:34:10 +01002754 select MFD_CORE
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002755 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002756 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002757
Daniel Drakecfee9592011-06-25 17:34:17 +01002758config OLPC_XO1_RTC
2759 bool "OLPC XO-1 Real Time Clock"
2760 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2761 ---help---
2762 Add support for the XO-1 real time clock, which can be used as a
2763 programmable wakeup source.
2764
Daniel Drake7feda8e2011-06-25 17:34:12 +01002765config OLPC_XO1_SCI
2766 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002767 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002768 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002769 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002770 ---help---
2771 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002772 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002773 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002774 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002775 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002776 - AC adapter status updates
2777 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002778
Daniel Drakea0f30f52011-06-25 17:34:18 +01002779config OLPC_XO15_SCI
2780 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002781 depends on OLPC && ACPI
2782 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002783 ---help---
2784 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2785 - EC-driven system wakeups
2786 - AC adapter status updates
2787 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002788
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002789config ALIX
2790 bool "PCEngines ALIX System Support (LED setup)"
2791 select GPIOLIB
2792 ---help---
2793 This option enables system support for the PCEngines ALIX.
2794 At present this just sets up LEDs for GPIO control on
2795 ALIX2/3/6 boards. However, other system specific setup should
2796 get added here.
2797
2798 Note: You must still enable the drivers for GPIO and LED support
2799 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2800
2801 Note: You have to set alix.force=1 for boards with Award BIOS.
2802
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002803config NET5501
2804 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2805 select GPIOLIB
2806 ---help---
2807 This option enables system support for the Soekris Engineering net5501.
2808
Philip A. Prindeville31970592012-01-14 01:45:39 -07002809config GEOS
2810 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2811 select GPIOLIB
2812 depends on DMI
2813 ---help---
2814 This option enables system support for the Traverse Technologies GEOS.
2815
Vivien Didelot7d029122013-01-04 16:18:14 -05002816config TS5500
2817 bool "Technologic Systems TS-5500 platform support"
2818 depends on MELAN
2819 select CHECK_SIGNATURE
2820 select NEW_LEDS
2821 select LEDS_CLASS
2822 ---help---
2823 This option enables system support for the Technologic Systems TS-5500.
2824
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002825endif # X86_32
2826
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002827config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002828 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002829 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002830
2831source "drivers/pcmcia/Kconfig"
2832
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002833config RAPIDIO
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002834 tristate "RapidIO support"
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002835 depends on PCI
2836 default n
2837 help
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002838 If enabled this option will include drivers and the core
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002839 infrastructure code to support RapidIO interconnect devices.
2840
2841source "drivers/rapidio/Kconfig"
2842
David Herrmanne3263ab2013-08-02 14:05:22 +02002843config X86_SYSFB
2844 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2845 help
2846 Firmwares often provide initial graphics framebuffers so the BIOS,
2847 bootloader or kernel can show basic video-output during boot for
2848 user-guidance and debugging. Historically, x86 used the VESA BIOS
2849 Extensions and EFI-framebuffers for this, which are mostly limited
2850 to x86.
2851 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2852 framebuffers so the new generic system-framebuffer drivers can be
2853 used on x86. If the framebuffer is not compatible with the generic
2854 modes, it is adverticed as fallback platform framebuffer so legacy
2855 drivers like efifb, vesafb and uvesafb can pick it up.
2856 If this option is not selected, all system framebuffers are always
2857 marked as fallback platform framebuffers as usual.
2858
2859 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2860 not be able to pick up generic system framebuffers if this option
2861 is selected. You are highly encouraged to enable simplefb as
2862 replacement if you select this option. simplefb can correctly deal
2863 with generic system framebuffers. But you should still keep vesafb
2864 and others enabled as fallback if a system framebuffer is
2865 incompatible with simplefb.
2866
2867 If unsure, say Y.
2868
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002869endmenu
2870
2871
2872menu "Executable file formats / Emulations"
2873
2874source "fs/Kconfig.binfmt"
2875
2876config IA32_EMULATION
2877 bool "IA32 Emulation"
2878 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002879 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002880 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002881 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002882 select COMPAT_OLD_SIGACTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002883 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002884 Include code to run legacy 32-bit programs under a
2885 64-bit kernel. You should likely turn this on, unless you're
2886 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002887
2888config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002889 tristate "IA32 a.out support"
2890 depends on IA32_EMULATION
2891 ---help---
2892 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002893
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002894config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002895 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002896 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002897 ---help---
2898 Include code to run binaries for the x32 native 32-bit ABI
2899 for 64-bit processors. An x32 process gets access to the
2900 full 64-bit register file and wide data path while leaving
2901 pointers at 32 bits for smaller memory footprint.
2902
2903 You will need a recent binutils (2.22 or later) with
2904 elf32_x86_64 support enabled to compile a kernel with this
2905 option set.
2906
Ingo Molnar953fee12016-11-15 10:22:52 +01002907config COMPAT_32
2908 def_bool y
2909 depends on IA32_EMULATION || X86_32
2910 select HAVE_UID16
2911 select OLD_SIGSUSPEND3
2912
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002913config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002914 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002915 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002916
Jan Beulich3120e252012-09-10 12:41:45 +01002917if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002918config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002919 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002920
2921config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002922 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002923 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002924endif
David Howellsee009e4a02011-03-07 15:06:20 +00002925
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002926endmenu
2927
2928
Keith Packarde5beae12008-11-03 18:21:45 +01002929config HAVE_ATOMIC_IOMAP
2930 def_bool y
2931 depends on X86_32
2932
Alessandro Rubini4692d772012-04-04 19:39:58 +02002933config X86_DEV_DMA_OPS
2934 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002935 depends on X86_64 || STA2X11
Alessandro Rubini4692d772012-04-04 19:39:58 +02002936
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002937config X86_DMA_REMAP
2938 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002939 depends on STA2X11
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002940
Kirill A. Shutemove5855132017-06-06 14:31:20 +03002941config HAVE_GENERIC_GUP
2942 def_bool y
2943
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002944source "net/Kconfig"
2945
2946source "drivers/Kconfig"
2947
2948source "drivers/firmware/Kconfig"
2949
2950source "fs/Kconfig"
2951
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002952source "arch/x86/Kconfig.debug"
2953
2954source "security/Kconfig"
2955
2956source "crypto/Kconfig"
2957
Avi Kivityedf88412007-12-16 11:02:48 +02002958source "arch/x86/kvm/Kconfig"
2959
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002960source "lib/Kconfig"