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Greg Kroah-Hartmanb2441312017-11-01 15:07:57 +01001# SPDX-License-Identifier: GPL-2.0
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01002# Select 32 or 64 bit
3config 64BIT
Sam Ravnborg68409992007-11-17 15:37:31 +01004 bool "64-bit kernel" if ARCH = "x86"
David Woodhouseffee0de2012-12-20 21:51:55 +00005 default ARCH != "i386"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01006 ---help---
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01007 Say yes to build a 64-bit kernel - formerly known as x86_64
8 Say no to build a 32-bit kernel - formerly known as i386
9
10config X86_32
Jan Beulich3120e252012-09-10 12:41:45 +010011 def_bool y
12 depends on !64BIT
Ingo Molnar341c7872016-11-15 10:04:55 +010013 # Options that are inherently 32-bit kernel only:
14 select ARCH_WANT_IPC_PARSE_VERSION
15 select CLKSRC_I8253
16 select CLONE_BACKWARDS
17 select HAVE_AOUT
18 select HAVE_GENERIC_DMA_COHERENT
19 select MODULES_USE_ELF_REL
20 select OLD_SIGACTION
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +010021
22config X86_64
Jan Beulich3120e252012-09-10 12:41:45 +010023 def_bool y
24 depends on 64BIT
Ingo Molnard94e0682016-11-15 10:11:57 +010025 # Options that are inherently 64-bit kernel only:
Aneesh Kumar K.Ve1073d12017-07-06 15:39:17 -070026 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
Ingo Molnard94e0682016-11-15 10:11:57 +010027 select ARCH_SUPPORTS_INT128
28 select ARCH_USE_CMPXCHG_LOCKREF
29 select HAVE_ARCH_SOFT_DIRTY
30 select MODULES_USE_ELF_RELA
Christoph Hellwigf616ab52018-05-09 06:53:49 +020031 select NEED_DMA_MAP_STATE
Christoph Hellwig09230cb2018-04-24 09:00:54 +020032 select SWIOTLB
Ingo Molnard94e0682016-11-15 10:11:57 +010033 select X86_DEV_DMA_OPS
Dominik Brodowskif8781c42018-04-05 11:53:05 +020034 select ARCH_HAS_SYSCALL_WRAPPER
Sam Ravnborg1032c0b2007-11-06 21:35:08 +010035
Ingo Molnard94e0682016-11-15 10:11:57 +010036#
37# Arch settings
38#
39# ( Note that options that are marked 'if X86_64' could in principle be
40# ported to 32-bit as well. )
41#
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +010042config X86
Harvey Harrison3c2362e2008-01-30 13:31:03 +010043 def_bool y
Ingo Molnarc763ea22016-11-15 10:26:39 +010044 #
45 # Note: keep this list sorted alphabetically
46 #
Ingo Molnar6471b822015-06-03 10:00:13 +020047 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
48 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
49 select ANON_INODES
50 select ARCH_CLOCKSOURCE_DATA
51 select ARCH_DISCARD_MEMBLOCK
Ingo Molnarc763ea22016-11-15 10:26:39 +010052 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
Laura Abbottfa5b6ec2017-01-10 13:35:40 -080053 select ARCH_HAS_DEBUG_VIRTUAL
Dan Williams21266be2015-11-19 18:19:29 -080054 select ARCH_HAS_DEVMEM_IS_ALLOWED
Ingo Molnar6471b822015-06-03 10:00:13 +020055 select ARCH_HAS_ELF_RANDOMIZE
Linus Torvalds72d93102014-09-13 11:14:53 -070056 select ARCH_HAS_FAST_MULTIPLIER
Dave Hansen316d0972018-04-20 15:20:28 -070057 select ARCH_HAS_FILTER_PGPROT
Daniel Micay6974f0c2017-07-12 14:36:10 -070058 select ARCH_HAS_FORTIFY_SOURCE
Riku Voipio957e3fa2014-12-12 16:57:44 -080059 select ARCH_HAS_GCOV_PROFILE_ALL
Dmitry Vyukov5c9a8752016-03-22 14:27:30 -070060 select ARCH_HAS_KCOV if X86_64
Mathieu Desnoyers10bcc802018-01-29 15:20:18 -050061 select ARCH_HAS_MEMBARRIER_SYNC_CORE
Ingo Molnarc763ea22016-11-15 10:26:39 +010062 select ARCH_HAS_PMEM_API if X86_64
Kees Cook39208aa2017-09-02 13:09:46 -070063 select ARCH_HAS_REFCOUNT
Dan Williams0aed55a2017-05-29 12:22:50 -070064 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Daniel Borkmannd2852a22017-02-21 16:09:33 +010065 select ARCH_HAS_SET_MEMORY
Ingo Molnar6471b822015-06-03 10:00:13 +020066 select ARCH_HAS_SG_CHAIN
Laura Abbottad21fc42017-02-06 16:31:57 -080067 select ARCH_HAS_STRICT_KERNEL_RWX
68 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050069 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Andrey Ryabininc6d30852016-01-20 15:00:55 -080070 select ARCH_HAS_UBSAN_SANITIZE_ALL
Oliver O'Halloran65f7d042017-06-28 11:32:31 +100071 select ARCH_HAS_ZONE_DEVICE if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020072 select ARCH_HAVE_NMI_SAFE_CMPXCHG
73 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040074 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080075 select ARCH_MIGHT_HAVE_PC_SERIO
Ingo Molnar6471b822015-06-03 10:00:13 +020076 select ARCH_SUPPORTS_ATOMIC_RMW
Ingo Molnar6471b822015-06-03 10:00:13 +020077 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
78 select ARCH_USE_BUILTIN_BSWAP
Ingo Molnar6471b822015-06-03 10:00:13 +020079 select ARCH_USE_QUEUED_RWLOCKS
80 select ARCH_USE_QUEUED_SPINLOCKS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -070081 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Ingo Molnarc763ea22016-11-15 10:26:39 +010082 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Huang Ying38d8b4e2017-07-06 15:37:18 -070083 select ARCH_WANTS_THP_SWAP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020084 select BUILDTIME_EXTABLE_SORT
85 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +020086 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
87 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +020088 select DCACHE_WORD_ACCESS
Christoph Hellwigfec777c2018-03-19 11:38:15 +010089 select DMA_DIRECT_OPS
Linus Torvalds45471cd2015-06-24 19:52:06 -070090 select EDAC_ATOMIC_SCRUB
91 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +020092 select GENERIC_CLOCKEVENTS
93 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
94 select GENERIC_CLOCKEVENTS_MIN_ADJUST
95 select GENERIC_CMOS_UPDATE
96 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +010097 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +020098 select GENERIC_EARLY_IOREMAP
99 select GENERIC_FIND_FIRST_BIT
100 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +0200101 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +0200102 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +0200103 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200104 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200105 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200106 select GENERIC_IRQ_SHOW
107 select GENERIC_PENDING_IRQ if SMP
108 select GENERIC_SMP_IDLE_THREAD
109 select GENERIC_STRNCPY_FROM_USER
110 select GENERIC_STRNLEN_USER
111 select GENERIC_TIME_VSYSCALL
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200112 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200113 select HAVE_ACPI_APEI if ACPI
114 select HAVE_ACPI_APEI_NMI if ACPI
115 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200116 select HAVE_ARCH_AUDITSYSCALL
117 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
118 select HAVE_ARCH_JUMP_LABEL
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800119 select HAVE_ARCH_KASAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200120 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800121 select HAVE_ARCH_MMAP_RND_BITS if MMU
122 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300123 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ingo Molnar6471b822015-06-03 10:00:13 +0200124 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700125 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Ingo Molnar6471b822015-06-03 10:00:13 +0200126 select HAVE_ARCH_TRACEHOOK
127 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Matthew Wilcoxa00cc7d2017-02-24 14:57:02 -0800128 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
Andy Lutomirskie37e43a2016-08-11 02:35:23 -0700129 select HAVE_ARCH_VMAP_STACK if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100130 select HAVE_ARCH_WITHIN_STACK_FRAMES
Ingo Molnar6471b822015-06-03 10:00:13 +0200131 select HAVE_CC_STACKPROTECTOR
132 select HAVE_CMPXCHG_DOUBLE
133 select HAVE_CMPXCHG_LOCAL
134 select HAVE_CONTEXT_TRACKING if X86_64
Josh Triplettc1bd55f2015-06-30 15:00:00 -0700135 select HAVE_COPY_THREAD_TLS
Ingo Molnar6471b822015-06-03 10:00:13 +0200136 select HAVE_C_RECORDMCOUNT
137 select HAVE_DEBUG_KMEMLEAK
138 select HAVE_DEBUG_STACKOVERFLOW
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700139 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400140 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900141 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Ingo Molnarc763ea22016-11-15 10:26:39 +0100142 select HAVE_EBPF_JIT if X86_64
Johannes Berg58340a02008-07-25 01:45:33 -0700143 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Jiri Slaby5f56a5d2016-05-20 17:00:16 -0700144 select HAVE_EXIT_THREAD
Steven Rostedt (VMware)644e0e82017-03-23 10:33:52 -0400145 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
Ingo Molnar6471b822015-06-03 10:00:13 +0200146 select HAVE_FTRACE_MCOUNT_RECORD
Ingo Molnar6471b822015-06-03 10:00:13 +0200147 select HAVE_FUNCTION_GRAPH_TRACER
148 select HAVE_FUNCTION_TRACER
Emese Revfy6b90bd42016-05-24 00:09:38 +0200149 select HAVE_GCC_PLUGINS
K.Prasad0067f122009-06-01 23:43:57 +0530150 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200151 select HAVE_IDE
152 select HAVE_IOREMAP_PROT
153 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
154 select HAVE_IRQ_TIME_ACCOUNTING
155 select HAVE_KERNEL_BZIP2
156 select HAVE_KERNEL_GZIP
157 select HAVE_KERNEL_LZ4
158 select HAVE_KERNEL_LZMA
159 select HAVE_KERNEL_LZO
160 select HAVE_KERNEL_XZ
161 select HAVE_KPROBES
162 select HAVE_KPROBES_ON_FTRACE
Masami Hiramatsu540adea2018-01-13 02:55:03 +0900163 select HAVE_FUNCTION_ERROR_INJECTION
Ingo Molnar6471b822015-06-03 10:00:13 +0200164 select HAVE_KRETPROBES
165 select HAVE_KVM
166 select HAVE_LIVEPATCH if X86_64
167 select HAVE_MEMBLOCK
168 select HAVE_MEMBLOCK_NODE_MAP
Frederic Weisbecker01027522010-04-11 18:55:56 +0200169 select HAVE_MIXED_BREAKPOINTS_REGS
Josh Poimboeufee9f8fc2017-07-24 18:36:57 -0500170 select HAVE_MOD_ARCH_SPECIFIC
Petr Mladek42a0bb32016-05-20 17:00:33 -0700171 select HAVE_NMI
Ingo Molnar6471b822015-06-03 10:00:13 +0200172 select HAVE_OPROFILE
173 select HAVE_OPTPROBES
174 select HAVE_PCSPKR_PLATFORM
175 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200176 select HAVE_PERF_EVENTS_NMI
Nicholas Piggin92e5aae2017-08-18 15:15:51 -0700177 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
Jiri Olsac5e63192012-08-07 15:20:36 +0200178 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200179 select HAVE_PERF_USER_STACK_DUMP
Vitaly Kuznetsov9e52fc22017-08-28 10:22:51 +0200180 select HAVE_RCU_TABLE_FREE
Ingo Molnar6471b822015-06-03 10:00:13 +0200181 select HAVE_REGS_AND_STACK_ACCESS_API
Josh Poimboeuf11af8472017-10-13 15:02:00 -0500182 select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
Ingo Molnarc763ea22016-11-15 10:26:39 +0100183 select HAVE_STACK_VALIDATION if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200184 select HAVE_SYSCALL_TRACEPOINTS
Ingo Molnar6471b822015-06-03 10:00:13 +0200185 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300186 select HAVE_USER_RETURN_NOTIFIER
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100187 select IRQ_FORCED_THREADING
Christoph Hellwig86596f02018-04-05 09:44:52 +0200188 select NEED_SG_DMA_LENGTH
Thomas Gleixnerdf65c1b2017-03-16 22:50:07 +0100189 select PCI_LOCKLESS_CONFIG
Ingo Molnar6471b822015-06-03 10:00:13 +0200190 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500191 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200192 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200193 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500194 select SRCU
Ingo Molnar6471b822015-06-03 10:00:13 +0200195 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700196 select THREAD_INFO_IN_TASK
Ingo Molnar6471b822015-06-03 10:00:13 +0200197 select USER_STACKTRACE_SUPPORT
198 select VIRT_TO_BUS
Ingo Molnar6471b822015-06-03 10:00:13 +0200199 select X86_FEATURE_NAMES if PROC_FS
Balbir Singh7d8330a2008-02-10 12:46:28 +0530200
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200201config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100202 def_bool y
203 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200204
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700205config OUTPUT_FORMAT
206 string
207 default "elf32-i386" if X86_32
208 default "elf64-x86-64" if X86_64
209
Sam Ravnborg73531902008-05-25 23:03:18 +0200210config ARCH_DEFCONFIG
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200211 string
Sam Ravnborg73531902008-05-25 23:03:18 +0200212 default "arch/x86/configs/i386_defconfig" if X86_32
213 default "arch/x86/configs/x86_64_defconfig" if X86_64
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200214
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100215config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100216 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100217
218config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100219 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100220
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100221config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100222 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100223
Daniel Cashman9e08f572016-01-14 15:20:06 -0800224config ARCH_MMAP_RND_BITS_MIN
225 default 28 if 64BIT
226 default 8
227
228config ARCH_MMAP_RND_BITS_MAX
229 default 32 if 64BIT
230 default 16
231
232config ARCH_MMAP_RND_COMPAT_BITS_MIN
233 default 8
234
235config ARCH_MMAP_RND_COMPAT_BITS_MAX
236 default 16
237
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100238config SBUS
239 bool
240
241config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100242 def_bool y
243 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100244
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100245config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100246 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100247 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000248 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
249
250config GENERIC_BUG_RELATIVE_POINTERS
251 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100252
253config GENERIC_HWEIGHT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100254 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100255
256config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100257 def_bool y
258 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100259
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100260config RWSEM_XCHGADD_ALGORITHM
Jan Beulich3120e252012-09-10 12:41:45 +0100261 def_bool y
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100262
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100263config GENERIC_CALIBRATE_DELAY
264 def_bool y
265
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800266config ARCH_HAS_CPU_RELAX
267 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100268
Pekka Enberg1b27d052008-04-28 02:12:22 -0700269config ARCH_HAS_CACHE_LINE_SIZE
270 def_bool y
271
Dave Hansen316d0972018-04-20 15:20:28 -0700272config ARCH_HAS_FILTER_PGPROT
273 def_bool y
274
Mike Travisdd5af902008-01-30 13:33:32 +0100275config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900276 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100277
Tejun Heo08fc4582009-08-14 15:00:49 +0900278config NEED_PER_CPU_EMBED_FIRST_CHUNK
279 def_bool y
280
281config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900282 def_bool y
283
Johannes Berg801e4062007-12-08 02:12:39 +0100284config ARCH_HIBERNATION_POSSIBLE
285 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100286
Johannes Bergf4cb5702007-12-08 02:14:00 +0100287config ARCH_SUSPEND_POSSIBLE
288 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100289
Steve Cappercfe28c52013-04-29 14:29:48 +0100290config ARCH_WANT_HUGE_PMD_SHARE
291 def_bool y
292
Steve Capper53313b22013-04-30 08:03:42 +0100293config ARCH_WANT_GENERAL_HUGETLB
294 def_bool y
295
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100296config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000297 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100298
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100299config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000300 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100301
Ingo Molnar765c68b2008-04-09 11:03:37 +0200302config ARCH_SUPPORTS_OPTIMIZED_INLINING
303 def_bool y
304
Akinobu Mita6a11f752009-03-31 15:23:17 -0700305config ARCH_SUPPORTS_DEBUG_PAGEALLOC
306 def_bool y
307
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300308config KASAN_SHADOW_OFFSET
309 hex
310 depends on KASAN
311 default 0xdffffc0000000000
312
Shane Wang69575d32009-09-01 18:25:07 -0700313config HAVE_INTEL_TXT
314 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700315 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700316
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100317config X86_32_SMP
318 def_bool y
319 depends on X86_32 && SMP
320
321config X86_64_SMP
322 def_bool y
323 depends on X86_64 && SMP
324
Tejun Heoccbeed32009-02-09 22:17:40 +0900325config X86_32_LAZY_GS
326 def_bool y
Kees Cook2bc2f682018-02-06 15:37:41 -0800327 depends on X86_32 && CC_STACKPROTECTOR_NONE
Tejun Heoccbeed32009-02-09 22:17:40 +0900328
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530329config ARCH_SUPPORTS_UPROBES
330 def_bool y
331
Rob Herringd20642f2014-04-18 17:19:54 -0500332config FIX_EARLYCON_MEM
333 def_bool y
334
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700335config PGTABLE_LEVELS
336 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300337 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700338 default 4 if X86_64
339 default 3 if X86_PAE
340 default 2
341
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100342source "init/Kconfig"
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700343source "kernel/Kconfig.freezer"
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100344
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100345menu "Processor type and features"
346
Randy Dunlap5ee71532012-01-16 11:57:18 -0800347config ZONE_DMA
348 bool "DMA memory allocation support" if EXPERT
349 default y
350 help
351 DMA memory allocation support allows devices with less than 32-bit
352 addressing to allocate within the first 16MB of address space.
353 Disable if no such devices will be used.
354
355 If unsure, say Y.
356
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100357config SMP
358 bool "Symmetric multi-processing support"
359 ---help---
360 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800361 a system with only one CPU, say N. If you have a system with more
362 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100363
Robert Graffham4a474152014-01-23 15:55:29 -0800364 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100365 machines, but will use only one CPU of a multiprocessor machine. If
366 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800367 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100368 will run faster if you say N here.
369
370 Note that if you say Y here and choose architecture "586" or
371 "Pentium" under "Processor family", the kernel will not work on 486
372 architectures. Similarly, multiprocessor kernels for the "PPro"
373 architecture may not work on all Pentium based boards.
374
375 People using multiprocessor machines who say Y here should also say
376 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
377 Management" code will be disabled if you say Y here.
378
Paul Bolle395cf962011-08-15 02:02:26 +0200379 See also <file:Documentation/x86/i386/IO-APIC.txt>,
Benjamin Petersonc9525a32017-05-20 17:20:16 -0700380 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100381 <http://www.tldp.org/docs.html#howto>.
382
383 If you don't know what to do here, say N.
384
Josh Triplett9def39be2013-10-30 08:09:45 -0700385config X86_FEATURE_NAMES
386 bool "Processor feature human-readable names" if EMBEDDED
387 default y
388 ---help---
389 This option compiles in a table of x86 feature bits and corresponding
390 names. This is required to support /proc/cpuinfo and a few kernel
391 messages. You can disable this to save space, at the expense of
392 making those few kernel messages show numeric feature bits instead.
393
394 If in doubt, say Y.
395
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800396config X86_X2APIC
397 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200398 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800399 ---help---
400 This enables x2apic support on CPUs that have this feature.
401
402 This allows 32-bit apic IDs (so it can support very large systems),
403 and accesses the local apic via MSRs not via mmio.
404
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800405 If you don't know what to do here, say N.
406
Yinghai Lu6695c852008-06-19 12:13:09 -0700407config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700408 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000409 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200410 depends on X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100411 ---help---
Yinghai Lu6695c852008-06-19 12:13:09 -0700412 For old smp systems that do not have proper acpi support. Newer systems
413 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700414
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000415config GOLDFISH
416 def_bool y
417 depends on X86_GOLDFISH
418
David Woodhouse76b04382018-01-11 21:46:25 +0000419config RETPOLINE
420 bool "Avoid speculative indirect branches in kernel"
421 default y
Peter Zijlstrad5028ba2018-02-06 09:46:13 +0100422 select STACK_VALIDATION if HAVE_STACK_VALIDATION
David Woodhouse76b04382018-01-11 21:46:25 +0000423 help
424 Compile kernel with the retpoline compiler options to guard against
425 kernel-to-user data leaks by avoiding speculative indirect
426 branches. Requires a compiler with -mindirect-branch=thunk-extern
427 support for full protection. The kernel may run slower.
428
429 Without compiler support, at least indirect branches in assembler
430 code are eliminated. Since this includes the syscall entry path,
431 it is not entirely pointless.
432
Vikas Shivappaf01d7d52017-07-25 14:14:22 -0700433config INTEL_RDT
434 bool "Intel Resource Director Technology support"
Fenghua Yu78e99b42016-10-22 06:19:53 -0700435 default n
436 depends on X86 && CPU_SUP_INTEL
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100437 select KERNFS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700438 help
Vikas Shivappaf01d7d52017-07-25 14:14:22 -0700439 Select to enable resource allocation and monitoring which are
440 sub-features of Intel Resource Director Technology(RDT). More
441 information about RDT can be found in the Intel x86
442 Architecture Software Developer Manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700443
444 Say N if unsure.
445
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800446if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800447config X86_BIGSMP
448 bool "Support for big SMP systems with more than 8 CPUs"
449 depends on SMP
450 ---help---
451 This option is needed for the systems that have more than 8 CPUs
452
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800453config X86_EXTENDED_PLATFORM
454 bool "Support for extended (non-PC) x86 platforms"
455 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100456 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100457 If you disable this option then the kernel will only support
458 standard PC platforms. (which covers the vast majority of
459 systems out there.)
460
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800461 If you enable this option then you'll be able to select support
462 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100463 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800464 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800465 RDC R-321x SoC
466 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200467 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200468 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100469
470 If you have one of these systems, or if you want to build a
471 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800472endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100473
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800474if X86_64
475config X86_EXTENDED_PLATFORM
476 bool "Support for extended (non-PC) x86 platforms"
477 default y
478 ---help---
479 If you disable this option then the kernel will only support
480 standard PC platforms. (which covers the vast majority of
481 systems out there.)
482
483 If you enable this option then you'll be able to select support
484 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800485 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800486 ScaleMP vSMP
487 SGI Ultraviolet
488
489 If you have one of these systems, or if you want to build a
490 generic distribution kernel, say Y here - otherwise say N.
491endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800492# This is an alphabetically sorted list of 64 bit extended platforms
493# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800494config X86_NUMACHIP
495 bool "Numascale NumaChip"
496 depends on X86_64
497 depends on X86_EXTENDED_PLATFORM
498 depends on NUMA
499 depends on SMP
500 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700501 depends on PCI_MMCONFIG
Steffen Persvold44b111b52011-12-06 00:07:26 +0800502 ---help---
503 Adds support for Numascale NumaChip large-SMP systems. Needed to
504 enable more than ~168 cores.
505 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100506
Ingo Molnar6a485652009-01-27 18:29:13 +0100507config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800508 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100509 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100510 select PARAVIRT
511 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800512 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300513 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100514 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100515 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
516 supposed to run on these EM64T-based machines. Only choose this option
517 if you have one of these machines.
518
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800519config X86_UV
520 bool "SGI Ultraviolet"
521 depends on X86_64
522 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500523 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800524 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700525 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200526 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800527 ---help---
528 This option is needed in order to support SGI Ultraviolet systems.
529 If you don't have one of these, you should say N here.
530
531# Following is an alphabetically sorted list of 32 bit extended platforms
532# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100533
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000534config X86_GOLDFISH
535 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100536 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000537 ---help---
538 Enable support for the Goldfish virtual platform used primarily
539 for Android development. Unless you are building for the Android
540 Goldfish emulator say N here.
541
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800542config X86_INTEL_CE
543 bool "CE4100 TV platform"
544 depends on PCI
545 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800546 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800547 depends on X86_32
548 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800549 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100550 select OF
551 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800552 ---help---
553 Select for the Intel CE media processor (CE4100) SOC.
554 This option compiles in support for the CE4100 SOC for settop
555 boxes and media devices.
556
David Cohen4cb9b002013-12-16 17:37:26 -0800557config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100558 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100559 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800560 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000561 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200562 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000563 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000564 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800565 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000566 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000567 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000568 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000569 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000570 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800571 Select to build a kernel capable of supporting Intel MID (Mobile
572 Internet Device) platform systems which do not have the PCI legacy
573 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000574
David Cohen4cb9b002013-12-16 17:37:26 -0800575 Intel MID platforms are based on an Intel processor and chipset which
576 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100577
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000578config X86_INTEL_QUARK
579 bool "Intel Quark platform support"
580 depends on X86_32
581 depends on X86_EXTENDED_PLATFORM
582 depends on X86_PLATFORM_DEVICES
583 depends on X86_TSC
584 depends on PCI
585 depends on PCI_GOANY
586 depends on X86_IO_APIC
587 select IOSF_MBI
588 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200589 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000590 ---help---
591 Select to include support for Quark X1000 SoC.
592 Say Y here if you have a Quark based system such as the Arduino
593 compatible Intel Galileo.
594
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000595config X86_INTEL_LPSS
596 bool "Intel Low Power Subsystem Support"
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100597 depends on X86 && ACPI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000598 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300599 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100600 select IOSF_MBI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000601 ---help---
602 Select to build support for Intel Low Power Subsystem such as
603 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300604 things like clock tree (common clock framework) and pincontrol
605 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000606
Ken Xue92082a82015-02-06 08:27:51 +0800607config X86_AMD_PLATFORM_DEVICE
608 bool "AMD ACPI2Platform devices support"
609 depends on ACPI
610 select COMMON_CLK
611 select PINCTRL
612 ---help---
613 Select to interpret AMD specific ACPI device to platform device
614 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
615 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
616 implemented under PINCTRL subsystem.
617
David E. Boxced3ce72014-09-17 22:13:50 -0700618config IOSF_MBI
619 tristate "Intel SoC IOSF Sideband support for SoC platforms"
620 depends on PCI
621 ---help---
622 This option enables sideband register access support for Intel SoC
623 platforms. On these platforms the IOSF sideband is used in lieu of
624 MSR's for some register accesses, mostly but not limited to thermal
625 and power. Drivers may query the availability of this device to
626 determine if they need the sideband in order to work on these
627 platforms. The sideband is available on the following SoC products.
628 This list is not meant to be exclusive.
629 - BayTrail
630 - Braswell
631 - Quark
632
633 You should say Y if you are running a kernel on one of these SoC's.
634
David E. Boxed2226b2014-09-17 22:13:51 -0700635config IOSF_MBI_DEBUG
636 bool "Enable IOSF sideband access through debugfs"
637 depends on IOSF_MBI && DEBUG_FS
638 ---help---
639 Select this option to expose the IOSF sideband access registers (MCR,
640 MDR, MCRX) through debugfs to write and read register information from
641 different units on the SoC. This is most useful for obtaining device
642 state information for debug and analysis. As this is a general access
643 mechanism, users of this option would have specific knowledge of the
644 device they want to access.
645
646 If you don't require the option or are in doubt, say N.
647
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800648config X86_RDC321X
649 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100650 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800651 depends on X86_EXTENDED_PLATFORM
652 select M486
653 select X86_REBOOTFIXUPS
654 ---help---
655 This option is needed for RDC R-321x system-on-chip, also known
656 as R-8610-(G).
657 If you don't have one of these chips, you should say N here.
658
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100659config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100660 bool "Support non-standard 32-bit SMP architectures"
661 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800662 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100663 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800664 This option compiles in the bigsmp and STA2X11 default
665 subarchitectures. It is intended for a generic binary
666 kernel. If you select them all, kernel will probe it one by
667 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700668
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800669# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700670
Linus Torvaldsd949f362009-09-26 09:35:07 -0700671config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100672 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700673 # MCE code calls memory_failure():
674 depends on X86_MCE
675 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700676 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
677 depends on X86_64 || !SPARSEMEM
678 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700679
Alessandro Rubini83125a32012-04-04 19:40:21 +0200680config STA2X11
681 bool "STA2X11 Companion Chip Support"
682 depends on X86_32_NON_STANDARD && PCI
Christoph Hellwigb6e05472018-03-19 11:38:24 +0100683 select ARCH_HAS_PHYS_TO_DMA
Alessandro Rubini83125a32012-04-04 19:40:21 +0200684 select X86_DEV_DMA_OPS
685 select X86_DMA_REMAP
686 select SWIOTLB
687 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200688 select GPIOLIB
Alessandro Rubini83125a32012-04-04 19:40:21 +0200689 default n
690 ---help---
691 This adds support for boards based on the STA2X11 IO-Hub,
692 a.k.a. "ConneXt". The chip is used in place of the standard
693 PC chipset, so all "standard" peripherals are missing. If this
694 option is selected the kernel will still be able to boot on
695 standard PC machines.
696
Shérab82148d12010-09-25 06:06:57 +0200697config X86_32_IRIS
698 tristate "Eurobraille/Iris poweroff module"
699 depends on X86_32
700 ---help---
701 The Iris machines from EuroBraille do not have APM or ACPI support
702 to shut themselves down properly. A special I/O sequence is
703 needed to do so, which is what this module does at
704 kernel shutdown.
705
706 This is only for Iris machines from EuroBraille.
707
708 If unused, say N.
709
Ingo Molnarae1e9132008-11-11 09:05:16 +0100710config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100711 def_bool y
712 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800713 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100714 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100715 Calculate simpler /proc/<PID>/wchan values. If this option
716 is disabled then wchan values will recurse back to the
717 caller function. This provides more accurate wchan values,
718 at the expense of slightly more scheduling overhead.
719
720 If in doubt, say "Y".
721
Borislav Petkov6276a072013-03-04 21:20:21 +0100722menuconfig HYPERVISOR_GUEST
723 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100724 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100725 Say Y here to enable options for running Linux under various hyper-
726 visors. This option enables basic hypervisor detection and platform
727 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100728
Borislav Petkov6276a072013-03-04 21:20:21 +0100729 If you say N, all options in this submenu will be skipped and
730 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100731
Borislav Petkov6276a072013-03-04 21:20:21 +0100732if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100733
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100734config PARAVIRT
735 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100736 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100737 This changes the kernel so it can modify itself when it is run
738 under a hypervisor, potentially improving performance significantly
739 over full virtualization. However, when run without a hypervisor
740 the kernel is theoretically slower and slightly larger.
741
Borislav Petkov6276a072013-03-04 21:20:21 +0100742config PARAVIRT_DEBUG
743 bool "paravirt-ops debugging"
744 depends on PARAVIRT && DEBUG_KERNEL
745 ---help---
746 Enable to debug paravirt_ops internals. Specifically, BUG if
747 a paravirt_op is missing when it is called.
748
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700749config PARAVIRT_SPINLOCKS
750 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700751 depends on PARAVIRT && SMP
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700752 ---help---
753 Paravirtualized spinlocks allow a pvops backend to replace the
754 spinlock implementation with something virtualization-friendly
755 (for example, block the virtual CPU rather than spinning).
756
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530757 It has a minimal impact on native kernels and gives a nice performance
758 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700759
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530760 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700761
Waiman Long45e898b2015-11-09 19:09:25 -0500762config QUEUED_LOCK_STAT
763 bool "Paravirt queued spinlock statistics"
Peter Zijlstracfd89832016-05-18 20:43:02 +0200764 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
Waiman Long45e898b2015-11-09 19:09:25 -0500765 ---help---
766 Enable the collection of statistical data on the slowpath
767 behavior of paravirtualized queued spinlocks and report
768 them on debugfs.
769
Borislav Petkov6276a072013-03-04 21:20:21 +0100770source "arch/x86/xen/Kconfig"
771
772config KVM_GUEST
773 bool "KVM Guest support (including kvmclock)"
774 depends on PARAVIRT
775 select PARAVIRT_CLOCK
776 default y
777 ---help---
778 This option enables various optimizations for running under the KVM
779 hypervisor. It includes a paravirtualized clock, so that instead
780 of relying on a PIT (or probably other) emulation by the
781 underlying device model, the host provides the guest with
782 timing infrastructure such as time of day, and system time
783
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530784config KVM_DEBUG_FS
785 bool "Enable debug information for KVM Guests in debugfs"
786 depends on KVM_GUEST && DEBUG_FS
787 default n
788 ---help---
789 This option enables collection of various statistics for KVM guest.
790 Statistics are displayed in debugfs filesystem. Enabling this option
791 may incur significant overhead.
792
Borislav Petkov6276a072013-03-04 21:20:21 +0100793config PARAVIRT_TIME_ACCOUNTING
794 bool "Paravirtual steal time accounting"
795 depends on PARAVIRT
796 default n
797 ---help---
798 Select this option to enable fine granularity task steal time
799 accounting. Time spent executing other tasks in parallel with
800 the current vCPU is discounted from the vCPU power. To account for
801 that, there can be a small performance impact.
802
803 If in doubt, say N here.
804
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200805config PARAVIRT_CLOCK
806 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200807
Jan Kiszka4a362602017-11-27 09:11:46 +0100808config JAILHOUSE_GUEST
809 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100810 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100811 select X86_PM_TIMER
Jan Kiszka4a362602017-11-27 09:11:46 +0100812 ---help---
813 This option allows to run Linux as guest in a Jailhouse non-root
814 cell. You can leave this option disabled if you only want to start
815 Jailhouse and run Linux afterwards in the root cell.
816
Borislav Petkov6276a072013-03-04 21:20:21 +0100817endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400818
Yinghai Lu08677212010-02-10 01:20:20 -0800819config NO_BOOTMEM
Yinghai Lu774ea0b2010-08-25 13:39:18 -0700820 def_bool y
Yinghai Lu08677212010-02-10 01:20:20 -0800821
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100822source "arch/x86/Kconfig.cpu"
823
824config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100825 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100826 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100827 ---help---
828 Use the IA-PC HPET (High Precision Event Timer) to manage
829 time in preference to the PIT and RTC, if a HPET is
830 present.
831 HPET is the next generation timer replacing legacy 8254s.
832 The HPET provides a stable time base on SMP
833 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200834 as it is off-chip. The interface used is documented
835 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100836
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100837 You can safely choose Y here. However, HPET will only be
838 activated if the platform and the BIOS support this feature.
839 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100840
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100841 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100842
843config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100844 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800845 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100846
Jacob Panbb24c472009-09-02 07:37:17 -0700847config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000848 def_bool y if X86_INTEL_MID
849 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100850 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000851 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700852 help
853 APB timer is the replacement for 8254, HPET on X86 MID platforms.
854 The APBT provides a stable time base on SMP
855 systems, unlike the TSC, but it is more expensive to access,
856 as it is off-chip. APB timers are always running regardless of CPU
857 C states, they are used as per CPU clockevent device when possible.
858
David Rientjes6a108a12011-01-20 14:44:16 -0800859# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100860# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700861config DMI
862 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800863 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800864 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100865 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700866 Enabled scanning of DMI to identify machine quirks. Say Y
867 here unless you have verified that your setup is not
868 affected by entries in the DMI blacklist. Required by PNP
869 BIOS code.
870
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100871config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700872 bool "Old AMD GART IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200873 select IOMMU_HELPER
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"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200895 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100896 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700897 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100898 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100899 Support for hardware IOMMUs in IBM's xSeries x366 and x460
900 systems. Needed to run systems with more than 3GB of memory
901 properly with 32-bit PCI devices that do not support DAC
902 (Double Address Cycle). Calgary also supports bus level
903 isolation, where all DMAs pass through the IOMMU. This
904 prevents them from going anywhere except their intended
905 destination. This catches hard-to-find kernel bugs and
906 mis-behaving drivers and devices that do not use the DMA-API
907 properly to set up their DMA buffers. The IOMMU can be
908 turned off at boot time with the iommu=off parameter.
909 Normally the kernel will make the right choice by itself.
910 If unsure, say Y.
911
912config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100913 def_bool y
914 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100915 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100916 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100917 Should Calgary be enabled by default? if you choose 'y', Calgary
918 will be used (if it exists). If you choose 'n', Calgary will not be
919 used even if it exists. If you choose 'n' and would like to use
920 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
921 If unsure, say Y.
922
Mike Travis1184dc22008-05-12 21:21:12 +0200923config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200924 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700925 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800926 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100927 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200928 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200929 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100930
Ingo Molnaraec64872018-02-10 12:36:29 +0100931#
932# The maximum number of CPUs supported:
933#
934# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
935# and which can be configured interactively in the
936# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
937#
938# The ranges are different on 32-bit and 64-bit kernels, depending on
939# hardware capabilities and scalability features of the kernel.
940#
941# ( If MAXSMP is enabled we just use the highest possible value and disable
942# interactive configuration. )
943#
944
945config NR_CPUS_RANGE_BEGIN
946 int
947 default NR_CPUS_RANGE_END if MAXSMP
948 default 1 if !SMP
949 default 2
950
951config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800952 int
953 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100954 default 64 if SMP && X86_BIGSMP
955 default 8 if SMP && !X86_BIGSMP
956 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800957
Ingo Molnaraec64872018-02-10 12:36:29 +0100958config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800959 int
960 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100961 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
962 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
963 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800964
Ingo Molnaraec64872018-02-10 12:36:29 +0100965config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800966 int
967 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100968 default 32 if X86_BIGSMP
969 default 8 if SMP
970 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800971
Ingo Molnaraec64872018-02-10 12:36:29 +0100972config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800973 int
974 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100975 default 8192 if MAXSMP
976 default 64 if SMP
977 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800978
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100979config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800980 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +0100981 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
982 default NR_CPUS_DEFAULT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100983 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100984 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500985 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +0300986 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100987 minimum value which makes sense is 2.
988
Ingo Molnaraec64872018-02-10 12:36:29 +0100989 This is purely to save memory: each supported CPU adds about 8KB
990 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100991
992config SCHED_SMT
993 bool "SMT (Hyperthreading) scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +0200994 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100995 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100996 SMT scheduler support improves the CPU scheduler's decision making
997 when dealing with Intel Pentium 4 chips with HyperThreading at a
998 cost of slightly increased overhead in some places. If unsure say
999 N here.
1000
1001config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001002 def_bool y
1003 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001004 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001005 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001006 Multi-core scheduler support improves the CPU scheduler's decision
1007 making when dealing with multi-core CPU chips at a cost of slightly
1008 increased overhead in some places. If unsure say N here.
1009
Tim Chende966cf2016-11-29 10:43:27 -08001010config SCHED_MC_PRIO
1011 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001012 depends on SCHED_MC && CPU_SUP_INTEL
1013 select X86_INTEL_PSTATE
1014 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001015 default y
Tim Chen5e76b2a2016-11-22 12:23:55 -08001016 ---help---
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001017 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1018 core ordering determined at manufacturing time, which allows
1019 certain cores to reach higher turbo frequencies (when running
1020 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001021
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001022 Enabling this kernel feature teaches the scheduler about
1023 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1024 scheduler's CPU selection logic accordingly, so that higher
1025 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001026
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001027 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001028
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001029 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001030
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001031source "kernel/Kconfig.preempt"
1032
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001033config UP_LATE_INIT
1034 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +01001035 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001036
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001037config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001038 bool "Local APIC support on uniprocessors" if !PCI_MSI
1039 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001040 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001041 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001042 A local APIC (Advanced Programmable Interrupt Controller) is an
1043 integrated interrupt controller in the CPU. If you have a single-CPU
1044 system which has a processor with a local APIC, you can say Y here to
1045 enable and use it. If you say Y here even though your machine doesn't
1046 have a local APIC, then the kernel will still run with no slowdown at
1047 all. The local APIC supports CPU-generated self-interrupts (timer,
1048 performance counters), and the NMI watchdog which detects hard
1049 lockups.
1050
1051config X86_UP_IOAPIC
1052 bool "IO-APIC support on uniprocessors"
1053 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001054 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001055 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1056 SMP-capable replacement for PC-style interrupt controllers. Most
1057 SMP systems and many recent uniprocessor systems have one.
1058
1059 If you have a single-CPU system with an IO-APIC, you can say Y here
1060 to use it. If you say Y here even though your machine doesn't have
1061 an IO-APIC, then the kernel will still run with no slowdown at all.
1062
1063config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001064 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001065 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001066 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001067 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001068
1069config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001070 def_bool y
1071 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001072
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001073config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1074 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001075 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001076 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001077 This option enables a workaround that fixes a source of
1078 spurious interrupts. This is recommended when threaded
1079 interrupt handling is used on systems where the generation of
1080 superfluous "boot interrupts" cannot be disabled.
1081
1082 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1083 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1084 kernel does during interrupt handling). On chipsets where this
1085 boot IRQ generation cannot be disabled, this workaround keeps
1086 the original IRQ line masked so that only the equivalent "boot
1087 IRQ" is delivered to the CPUs. The workaround also tells the
1088 kernel to set up the IRQ handler on the boot IRQ line. In this
1089 way only one interrupt is delivered to the kernel. Otherwise
1090 the spurious second interrupt may cause the kernel to bring
1091 down (vital) interrupt lines.
1092
1093 Only affects "broken" chipsets. Interrupt sharing may be
1094 increased on these systems.
1095
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001096config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001097 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001098 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001099 default y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001100 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +02001101 Machine Check support allows the processor to notify the
1102 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001103 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001104 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001105
Tony Luck5de97c92017-03-27 11:33:03 +02001106config X86_MCELOG_LEGACY
1107 bool "Support for deprecated /dev/mcelog character device"
1108 depends on X86_MCE
1109 ---help---
1110 Enable support for /dev/mcelog which is needed by the old mcelog
1111 userspace logging daemon. Consider switching to the new generation
1112 rasdaemon solution.
1113
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001114config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001115 def_bool y
1116 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001117 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001118 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001119 Additional support for intel specific MCE features such as
1120 the thermal monitor.
1121
1122config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001123 def_bool y
1124 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001125 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001126 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001127 Additional support for AMD specific MCE features such as
1128 the DRAM Error Threshold.
1129
Andi Kleen4efc0672009-04-28 19:07:31 +02001130config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001131 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001132 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001133 ---help---
1134 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001135 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001136 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001137
Andi Kleenb2762682009-02-12 13:49:31 +01001138config X86_MCE_THRESHOLD
1139 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001140 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001141
Andi Kleenea149b32009-04-29 19:31:00 +02001142config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001143 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001144 tristate "Machine check injector support"
1145 ---help---
1146 Provide support for injecting machine checks for testing purposes.
1147 If you don't know what a machine check is and you don't do kernel
1148 QA it is safe to say n.
1149
Andi Kleen4efc0672009-04-28 19:07:31 +02001150config X86_THERMAL_VECTOR
1151 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001152 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001153
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001154source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001155
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001156config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001157 bool "Legacy VM86 support"
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001158 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001159 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001160 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001161 This option allows user programs to put the CPU into V8086
1162 mode, which is an 80286-era approximation of 16-bit real mode.
1163
1164 Some very old versions of X and/or vbetool require this option
1165 for user mode setting. Similarly, DOSEMU will use it if
1166 available to accelerate real mode DOS programs. However, any
1167 recent version of DOSEMU, X, or vbetool should be fully
1168 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001169 fall back to software emulation. Nevertheless, if you are using
1170 a 16-bit DOS program where 16-bit performance matters, vm86
1171 mode might be faster than emulation and you might want to
1172 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001173
Ingo Molnar1e642812015-09-05 08:58:10 +02001174 Note that any app that works on a 64-bit kernel is unlikely to
1175 need this option, as 64-bit kernels don't, and can't, support
1176 V8086 mode. This option is also unrelated to 16-bit protected
1177 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001178
Ingo Molnar1e642812015-09-05 08:58:10 +02001179 Enabling this option increases the complexity of the kernel
1180 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001181
Ingo Molnar1e642812015-09-05 08:58:10 +02001182 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001183
1184config VM86
1185 bool
1186 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001187
1188config X86_16BIT
1189 bool "Enable support for 16-bit segments" if EXPERT
1190 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001191 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001192 ---help---
1193 This option is required by programs like Wine to run 16-bit
1194 protected mode legacy code on x86 processors. Disabling
1195 this option saves about 300 bytes on i386, or around 6K text
1196 plus 16K runtime memory on x86-64,
1197
1198config X86_ESPFIX32
1199 def_bool y
1200 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001201
H. Peter Anvin197725d2014-05-04 10:00:49 -07001202config X86_ESPFIX64
1203 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001204 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001205
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001206config X86_VSYSCALL_EMULATION
1207 bool "Enable vsyscall emulation" if EXPERT
1208 default y
1209 depends on X86_64
1210 ---help---
1211 This enables emulation of the legacy vsyscall page. Disabling
1212 it is roughly equivalent to booting with vsyscall=none, except
1213 that it will also disable the helpful warning if a program
1214 tries to use a vsyscall. With this option set to N, offending
1215 programs will just segfault, citing addresses of the form
1216 0xffffffffff600?00.
1217
1218 This option is required by many programs built before 2013, and
1219 care should be used even with newer programs if set to N.
1220
1221 Disabling this option saves about 7K of kernel size and
1222 possibly 4K of additional runtime pagetable memory.
1223
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001224config TOSHIBA
1225 tristate "Toshiba Laptop support"
1226 depends on X86_32
1227 ---help---
1228 This adds a driver to safely access the System Management Mode of
1229 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1230 not work on models with a Phoenix BIOS. The System Management Mode
1231 is used to set the BIOS and power saving options on Toshiba portables.
1232
1233 For information on utilities to make use of this driver see the
1234 Toshiba Linux utilities web site at:
1235 <http://www.buzzard.org.uk/toshiba/>.
1236
1237 Say Y if you intend to run this kernel on a Toshiba portable.
1238 Say N otherwise.
1239
1240config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001241 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001242 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001243 select SENSORS_DELL_SMM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001244 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001245 This option enables legacy /proc/i8k userspace interface in hwmon
1246 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1247 temperature and allows controlling fan speeds of Dell laptops via
1248 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1249 it reports also power and hotkey status. For fan speed control is
1250 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001251
Pali Rohár039ae582015-05-14 13:16:37 +02001252 Say Y if you intend to run this kernel on old Dell laptops or want to
1253 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001254 Say N otherwise.
1255
1256config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001257 bool "Enable X86 board specific fixups for reboot"
1258 depends on X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001259 ---help---
1260 This enables chipset and/or board specific fixups to be done
1261 in order to get reboot to work correctly. This is only needed on
1262 some combinations of hardware and BIOS. The symptom, for which
1263 this config is intended, is when reboot ends with a stalled/hung
1264 system.
1265
1266 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001267 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001268
1269 Say Y if you want to enable the fixup. Currently, it's safe to
1270 enable this option even if you don't need it.
1271 Say N otherwise.
1272
1273config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001274 bool "CPU microcode loading support"
1275 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001276 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001277 select FW_LOADER
1278 ---help---
1279 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001280 Intel and AMD processors. The Intel support is for the IA32 family,
1281 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1282 AMD support is for families 0x10 and later. You will obviously need
1283 the actual microcode binary data itself which is not shipped with
1284 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001285
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001286 The preferred method to load microcode from a detached initrd is described
Jaak Ristioja1897a962018-02-09 11:22:16 +02001287 in Documentation/x86/microcode.txt. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001288 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1289 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001290
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001291 In addition, you can build the microcode into the kernel. For that you
1292 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1293 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001294
Peter Oruba8d86f392008-07-28 18:44:21 +02001295config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001296 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001297 depends on MICROCODE
1298 default MICROCODE
1299 select FW_LOADER
1300 ---help---
1301 This options enables microcode patch loading support for Intel
1302 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001303
Alanb8989db2014-01-20 18:01:56 +00001304 For the current Intel microcode data package go to
1305 <https://downloadcenter.intel.com> and search for
1306 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001307
Peter Oruba80cc9f12008-07-28 18:44:22 +02001308config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001309 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001310 depends on MICROCODE
1311 select FW_LOADER
1312 ---help---
1313 If you select this option, microcode patch loading support for AMD
1314 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001315
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001316config MICROCODE_OLD_INTERFACE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001317 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001318 depends on MICROCODE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001319
1320config X86_MSR
1321 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001322 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001323 This device gives privileged processes access to the x86
1324 Model-Specific Registers (MSRs). It is a character device with
1325 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1326 MSR accesses are directed to a specific CPU on multi-processor
1327 systems.
1328
1329config X86_CPUID
1330 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001331 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001332 This device gives processes access to the x86 CPUID instruction to
1333 be executed on a specific processor. It is a character device
1334 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1335 /dev/cpu/31/cpuid.
1336
1337choice
1338 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001339 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001340 depends on X86_32
1341
1342config NOHIGHMEM
1343 bool "off"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001344 ---help---
1345 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1346 However, the address space of 32-bit x86 processors is only 4
1347 Gigabytes large. That means that, if you have a large amount of
1348 physical memory, not all of it can be "permanently mapped" by the
1349 kernel. The physical memory that's not permanently mapped is called
1350 "high memory".
1351
1352 If you are compiling a kernel which will never run on a machine with
1353 more than 1 Gigabyte total physical RAM, answer "off" here (default
1354 choice and suitable for most users). This will result in a "3GB/1GB"
1355 split: 3GB are mapped so that each process sees a 3GB virtual memory
1356 space and the remaining part of the 4GB virtual memory space is used
1357 by the kernel to permanently map as much physical memory as
1358 possible.
1359
1360 If the machine has between 1 and 4 Gigabytes physical RAM, then
1361 answer "4GB" here.
1362
1363 If more than 4 Gigabytes is used then answer "64GB" here. This
1364 selection turns Intel PAE (Physical Address Extension) mode on.
1365 PAE implements 3-level paging on IA32 processors. PAE is fully
1366 supported by Linux, PAE mode is implemented on all recent Intel
1367 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1368 then the kernel will not boot on CPUs that don't support PAE!
1369
1370 The actual amount of total physical memory will either be
1371 auto detected or can be forced by using a kernel command line option
1372 such as "mem=256M". (Try "man bootparam" or see the documentation of
1373 your boot loader (lilo or loadlin) about how to pass options to the
1374 kernel at boot time.)
1375
1376 If unsure, say "off".
1377
1378config HIGHMEM4G
1379 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001380 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001381 Select this if you have a 32-bit processor and between 1 and 4
1382 gigabytes of physical RAM.
1383
1384config HIGHMEM64G
1385 bool "64GB"
Matthew Whitehead69b8d3f2018-02-15 11:54:55 -05001386 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001387 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001388 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001389 Select this if you have a 32-bit processor and more than 4
1390 gigabytes of physical RAM.
1391
1392endchoice
1393
1394choice
David Rientjes6a108a12011-01-20 14:44:16 -08001395 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001396 default VMSPLIT_3G
1397 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001398 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001399 Select the desired split between kernel and user memory.
1400
1401 If the address range available to the kernel is less than the
1402 physical memory installed, the remaining memory will be available
1403 as "high memory". Accessing high memory is a little more costly
1404 than low memory, as it needs to be mapped into the kernel first.
1405 Note that increasing the kernel address space limits the range
1406 available to user programs, making the address space there
1407 tighter. Selecting anything other than the default 3G/1G split
1408 will also likely make your kernel incompatible with binary-only
1409 kernel modules.
1410
1411 If you are not absolutely sure what you are doing, leave this
1412 option alone!
1413
1414 config VMSPLIT_3G
1415 bool "3G/1G user/kernel split"
1416 config VMSPLIT_3G_OPT
1417 depends on !X86_PAE
1418 bool "3G/1G user/kernel split (for full 1G low memory)"
1419 config VMSPLIT_2G
1420 bool "2G/2G user/kernel split"
1421 config VMSPLIT_2G_OPT
1422 depends on !X86_PAE
1423 bool "2G/2G user/kernel split (for full 2G low memory)"
1424 config VMSPLIT_1G
1425 bool "1G/3G user/kernel split"
1426endchoice
1427
1428config PAGE_OFFSET
1429 hex
1430 default 0xB0000000 if VMSPLIT_3G_OPT
1431 default 0x80000000 if VMSPLIT_2G
1432 default 0x78000000 if VMSPLIT_2G_OPT
1433 default 0x40000000 if VMSPLIT_1G
1434 default 0xC0000000
1435 depends on X86_32
1436
1437config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001438 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001439 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001440
1441config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001442 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001443 depends on X86_32 && !HIGHMEM4G
Christoph Hellwigd4a451d2018-04-03 16:24:20 +02001444 select PHYS_ADDR_T_64BIT
Christian Melki9d99c712015-10-05 17:31:33 +02001445 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001446 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001447 PAE is required for NX support, and furthermore enables
1448 larger swapspace support for non-overcommit purposes. It
1449 has the cost of more pagetable lookup overhead, and also
1450 consumes more pagetable space per process.
1451
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001452config X86_5LEVEL
1453 bool "Enable 5-level page tables support"
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001454 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001455 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001456 depends on X86_64
1457 ---help---
1458 5-level paging enables access to larger address space:
1459 upto 128 PiB of virtual address space and 4 PiB of
1460 physical address space.
1461
1462 It will be supported by future Intel CPUs.
1463
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001464 A kernel with the option enabled can be booted on machines that
1465 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001466
1467 See Documentation/x86/x86_64/5level-paging.txt for more
1468 information.
1469
1470 Say N if unsure.
1471
Ingo Molnar10971ab2015-03-05 08:18:23 +01001472config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001473 def_bool y
Levin, Alexander (Sasha Levin)4675ff02017-11-15 17:36:02 -08001474 depends on X86_64 && !DEBUG_PAGEALLOC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001475 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001476 Certain kernel features effectively disable kernel
1477 linear 1 GB mappings (even if the CPU otherwise
1478 supports them), so don't confuse the user by printing
1479 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001480
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001481config ARCH_HAS_MEM_ENCRYPT
1482 def_bool y
1483
1484config AMD_MEM_ENCRYPT
1485 bool "AMD Secure Memory Encryption (SME) support"
1486 depends on X86_64 && CPU_SUP_AMD
1487 ---help---
1488 Say yes to enable support for the encryption of system memory.
1489 This requires an AMD processor that supports Secure Memory
1490 Encryption (SME).
1491
1492config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1493 bool "Activate AMD Secure Memory Encryption (SME) by default"
1494 default y
1495 depends on AMD_MEM_ENCRYPT
1496 ---help---
1497 Say yes to have system memory encrypted by default if running on
1498 an AMD processor that supports Secure Memory Encryption (SME).
1499
1500 If set to Y, then the encryption of system memory can be
1501 deactivated with the mem_encrypt=off command line option.
1502
1503 If set to N, then the encryption of system memory can be
1504 activated with the mem_encrypt=on command line option.
1505
Tom Lendackyf88a68f2017-07-17 16:10:09 -05001506config ARCH_USE_MEMREMAP_PROT
1507 def_bool y
1508 depends on AMD_MEM_ENCRYPT
1509
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001510# Common NUMA Features
1511config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001512 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001513 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001514 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1515 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001516 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001517 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001518
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001519 The kernel will try to allocate memory used by a CPU on the
1520 local memory controller of the CPU and add some more
1521 NUMA awareness to the kernel.
1522
Ingo Molnarc280ea52008-11-08 13:29:45 +01001523 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001524 (or later), AMD Opteron, or EM64T NUMA.
1525
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001526 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001527 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001528
1529 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001530
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001531config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001532 def_bool y
1533 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001534 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001535 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001536 Enable AMD NUMA node topology detection. You should say Y here if
1537 you have a multi processor AMD system. This uses an old method to
1538 read the NUMA configuration directly from the builtin Northbridge
1539 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1540 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001541
1542config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001543 def_bool y
1544 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001545 depends on X86_64 && NUMA && ACPI && PCI
1546 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001547 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001548 Enable ACPI SRAT based node topology detection.
1549
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001550# Some NUMA nodes have memory ranges that span
1551# other nodes. Even though a pfn is valid and
1552# between a node's start and end pfns, it may not
1553# reside on that node. See memmap_init_zone()
1554# for details.
1555config NODES_SPAN_OTHER_NODES
1556 def_bool y
1557 depends on X86_64_ACPI_NUMA
1558
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001559config NUMA_EMU
1560 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001561 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001562 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001563 Enable NUMA emulation. A flat machine will be split
1564 into virtual nodes when booted with "numa=fake=N", where N is the
1565 number of nodes. This is only useful for debugging.
1566
1567config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001568 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001569 range 1 10
1570 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001571 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001572 default "3"
1573 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001574 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001575 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001576 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001577
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001578config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001579 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001580 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001581
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001582config ARCH_FLATMEM_ENABLE
1583 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001584 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001585
1586config ARCH_DISCONTIGMEM_ENABLE
1587 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001588 depends on NUMA && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001589
1590config ARCH_DISCONTIGMEM_DEFAULT
1591 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001592 depends on NUMA && X86_32
1593
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001594config ARCH_SPARSEMEM_ENABLE
1595 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001596 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001597 select SPARSEMEM_STATIC if X86_32
1598 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1599
Tejun Heo3b166512011-04-01 11:15:12 +02001600config ARCH_SPARSEMEM_DEFAULT
1601 def_bool y
1602 depends on X86_64
1603
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001604config ARCH_SELECT_MEMORY_MODEL
1605 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001606 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001607
1608config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001609 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001610 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001611 help
1612 This option enables a sysfs memory/probe interface for testing.
1613 See Documentation/memory-hotplug.txt for more information.
1614 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001615
Tejun Heo3b166512011-04-01 11:15:12 +02001616config ARCH_PROC_KCORE_TEXT
1617 def_bool y
1618 depends on X86_64 && PROC_KCORE
1619
Avi Kivitya29815a2010-01-10 16:28:09 +02001620config ILLEGAL_POINTER_VALUE
1621 hex
1622 default 0 if X86_32
1623 default 0xdead000000000000 if X86_64
1624
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001625source "mm/Kconfig"
1626
Dan Williams7a678322015-08-19 00:34:34 -04001627config X86_PMEM_LEGACY_DEVICE
1628 bool
1629
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001630config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001631 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001632 depends on PHYS_ADDR_T_64BIT
1633 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001634 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001635 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001636 help
1637 Treat memory marked using the non-standard e820 type of 12 as used
1638 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1639 The kernel will offer these regions to the 'pmem' driver so
1640 they can be used for persistent storage.
1641
1642 Say Y if unsure.
1643
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001644config HIGHPTE
1645 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001646 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001647 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001648 The VM uses one page table entry for each page of physical memory.
1649 For systems with a lot of RAM, this can be wasteful of precious
1650 low memory. Setting this option will put user-space page table
1651 entries in high memory.
1652
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001653config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001654 bool "Check for low memory corruption"
1655 ---help---
1656 Periodically check for memory corruption in low memory, which
1657 is suspected to be caused by BIOS. Even when enabled in the
1658 configuration, it is disabled at runtime. Enable it by
1659 setting "memory_corruption_check=1" on the kernel command
1660 line. By default it scans the low 64k of memory every 60
1661 seconds; see the memory_corruption_check_size and
1662 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001663 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001664
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001665 When enabled with the default parameters, this option has
1666 almost no overhead, as it reserves a relatively small amount
1667 of memory and scans it infrequently. It both detects corruption
1668 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001669
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001670 It is, however, intended as a diagnostic tool; if repeatable
1671 BIOS-originated corruption always affects the same memory,
1672 you can use memmap= to prevent the kernel from using that
1673 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001674
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001675config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001676 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001677 depends on X86_CHECK_BIOS_CORRUPTION
1678 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001679 ---help---
1680 Set whether the default state of memory_corruption_check is
1681 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001682
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001683config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001684 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1685 default 64
1686 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001687 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001688 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001689
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001690 The first page contains BIOS data structures that the kernel
1691 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001692
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001693 By default we reserve the first 64K of physical RAM, as a
1694 number of BIOSes are known to corrupt that memory range
1695 during events such as suspend/resume or monitor cable
1696 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001697
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001698 You can set this to 4 if you are absolutely sure that you
1699 trust the BIOS to get all its memory reservations and usages
1700 right. If you know your BIOS have problems beyond the
1701 default 64K area, you can set this to 640 to avoid using the
1702 entire low memory range.
1703
1704 If you have doubts about the BIOS (e.g. suspend/resume does
1705 not work or there's kernel crashes after certain hardware
1706 hotplug events) then you might want to enable
1707 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1708 typical corruption patterns.
1709
1710 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001711
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001712config MATH_EMULATION
1713 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001714 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001715 prompt "Math emulation" if X86_32
1716 ---help---
1717 Linux can emulate a math coprocessor (used for floating point
1718 operations) if you don't have one. 486DX and Pentium processors have
1719 a math coprocessor built in, 486SX and 386 do not, unless you added
1720 a 487DX or 387, respectively. (The messages during boot time can
1721 give you some hints here ["man dmesg"].) Everyone needs either a
1722 coprocessor or this emulation.
1723
1724 If you don't have a math coprocessor, you need to say Y here; if you
1725 say Y here even though you have a coprocessor, the coprocessor will
1726 be used nevertheless. (This behavior can be changed with the kernel
1727 command line option "no387", which comes handy if your coprocessor
1728 is broken. Try "man bootparam" or see the documentation of your boot
1729 loader (lilo or loadlin) about how to pass options to the kernel at
1730 boot time.) This means that it is a good idea to say Y here if you
1731 intend to use this kernel on different machines.
1732
1733 More information about the internals of the Linux math coprocessor
1734 emulation can be found in <file:arch/x86/math-emu/README>.
1735
1736 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1737 kernel, it won't hurt.
1738
1739config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001740 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001741 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001742 ---help---
1743 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1744 the Memory Type Range Registers (MTRRs) may be used to control
1745 processor access to memory ranges. This is most useful if you have
1746 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1747 allows bus write transfers to be combined into a larger transfer
1748 before bursting over the PCI/AGP bus. This can increase performance
1749 of image write operations 2.5 times or more. Saying Y here creates a
1750 /proc/mtrr file which may be used to manipulate your processor's
1751 MTRRs. Typically the X server should use this.
1752
1753 This code has a reasonably generic interface so that similar
1754 control registers on other processors can be easily supported
1755 as well:
1756
1757 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1758 Registers (ARRs) which provide a similar functionality to MTRRs. For
1759 these, the ARRs are used to emulate the MTRRs.
1760 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1761 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1762 write-combining. All of these processors are supported by this code
1763 and it makes sense to say Y here if you have one of them.
1764
1765 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1766 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1767 can lead to all sorts of problems, so it's good to say Y here.
1768
1769 You can safely say Y even if your machine doesn't have MTRRs, you'll
1770 just add about 9 KB to your kernel.
1771
Randy Dunlap7225e752008-07-26 17:54:22 -07001772 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001773
Yinghai Lu95ffa242008-04-29 03:52:33 -07001774config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001775 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001776 prompt "MTRR cleanup support"
1777 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001778 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001779 Convert MTRR layout from continuous to discrete, so X drivers can
1780 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001781
Thomas Gleixneraba37282008-07-15 14:48:48 +02001782 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001783 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001784 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001785
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001786 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001787
1788config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001789 int "MTRR cleanup enable value (0-1)"
1790 range 0 1
1791 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001792 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001793 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001794 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001795
Yinghai Lu12031a62008-05-02 02:40:22 -07001796config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1797 int "MTRR cleanup spare reg num (0-7)"
1798 range 0 7
1799 default "1"
1800 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001801 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001802 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001803 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001804
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001805config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001806 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001807 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001808 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001809 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001810 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001811
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001812 PATs are the modern equivalents of MTRRs and are much more
1813 flexible than MTRRs.
1814
1815 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001816 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001817
1818 If unsure, say Y.
1819
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001820config ARCH_USES_PG_UNCACHED
1821 def_bool y
1822 depends on X86_PAT
1823
H. Peter Anvin628c6242011-07-31 13:59:29 -07001824config ARCH_RANDOM
1825 def_bool y
1826 prompt "x86 architectural random number generator" if EXPERT
1827 ---help---
1828 Enable the x86 architectural RDRAND instruction
1829 (Intel Bull Mountain technology) to generate random numbers.
1830 If supported, this is a high bandwidth, cryptographically
1831 secure hardware random number generator.
1832
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001833config X86_SMAP
1834 def_bool y
1835 prompt "Supervisor Mode Access Prevention" if EXPERT
1836 ---help---
1837 Supervisor Mode Access Prevention (SMAP) is a security
1838 feature in newer Intel processors. There is a small
1839 performance cost if this enabled and turned on; there is
1840 also a small increase in the kernel size if this is enabled.
1841
1842 If unsure, say Y.
1843
Ricardo Neriaa35f892017-11-05 18:27:54 -08001844config X86_INTEL_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001845 def_bool y
Ricardo Neriaa35f892017-11-05 18:27:54 -08001846 depends on CPU_SUP_INTEL
1847 prompt "Intel User Mode Instruction Prevention" if EXPERT
1848 ---help---
1849 The User Mode Instruction Prevention (UMIP) is a security
1850 feature in newer Intel processors. If enabled, a general
Ricardo Neri796ebc82017-11-13 22:29:42 -08001851 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1852 or STR instructions are executed in user mode. These instructions
1853 unnecessarily expose information about the hardware state.
1854
1855 The vast majority of applications do not use these instructions.
1856 For the very few that do, software emulation is provided in
1857 specific cases in protected and virtual-8086 modes. Emulated
1858 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001859
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001860config X86_INTEL_MPX
1861 prompt "Intel MPX (Memory Protection Extensions)"
1862 def_bool n
Rik van Rieldf3735c2017-09-06 16:25:11 -07001863 # Note: only available in 64-bit mode due to VMA flags shortage
1864 depends on CPU_SUP_INTEL && X86_64
1865 select ARCH_USES_HIGH_VMA_FLAGS
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001866 ---help---
1867 MPX provides hardware features that can be used in
1868 conjunction with compiler-instrumented code to check
1869 memory references. It is designed to detect buffer
1870 overflow or underflow bugs.
1871
1872 This option enables running applications which are
1873 instrumented or otherwise use MPX. It does not use MPX
1874 itself inside the kernel or to protect the kernel
1875 against bad memory references.
1876
1877 Enabling this option will make the kernel larger:
1878 ~8k of kernel text and 36 bytes of data on a 64-bit
1879 defconfig. It adds a long to the 'mm_struct' which
1880 will increase the kernel memory overhead of each
1881 process and adds some branches to paths used during
1882 exec() and munmap().
1883
1884 For details, see Documentation/x86/intel_mpx.txt
1885
1886 If unsure, say N.
1887
Dave Hansen35e97792016-02-12 13:02:00 -08001888config X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001889 prompt "Intel Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001890 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001891 # Note: only available in 64-bit mode
Dave Hansen35e97792016-02-12 13:02:00 -08001892 depends on CPU_SUP_INTEL && X86_64
Ingo Molnar52c8e602016-11-15 10:15:03 +01001893 select ARCH_USES_HIGH_VMA_FLAGS
1894 select ARCH_HAS_PKEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001895 ---help---
1896 Memory Protection Keys provides a mechanism for enforcing
1897 page-based protections, but without requiring modification of the
1898 page tables when an application changes protection domains.
1899
1900 For details, see Documentation/x86/protection-keys.txt
1901
1902 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001903
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001904config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001905 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001906 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001907 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001908 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001909 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001910 This enables the kernel to use EFI runtime services that are
1911 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001912
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001913 This option is only useful on systems that have EFI firmware.
1914 In addition, you should use the latest ELILO loader available
1915 at <http://elilo.sourceforge.net> in order to take advantage
1916 of EFI runtime services. However, even with this option, the
1917 resultant kernel should continue to boot on existing non-EFI
1918 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001919
Matt Fleming291f3632011-12-12 21:27:52 +00001920config EFI_STUB
1921 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001922 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001923 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001924 ---help---
1925 This kernel feature allows a bzImage to be loaded directly
1926 by EFI firmware without the use of a bootloader.
1927
Roy Franz4172fe22013-09-22 15:45:25 -07001928 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001929
Matt Fleming7d453ee2014-01-10 18:52:06 +00001930config EFI_MIXED
1931 bool "EFI mixed-mode support"
1932 depends on EFI_STUB && X86_64
1933 ---help---
1934 Enabling this feature allows a 64-bit kernel to be booted
1935 on a 32-bit firmware, provided that your CPU supports 64-bit
1936 mode.
1937
1938 Note that it is not possible to boot a mixed-mode enabled
1939 kernel via the EFI boot stub - a bootloader that supports
1940 the EFI handover protocol must be used.
1941
1942 If unsure, say N.
1943
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001944config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001945 def_bool y
1946 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001947 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001948 This kernel feature is useful for number crunching applications
1949 that may need to compute untrusted bytecode during their
1950 execution. By using pipes or other transports made available to
1951 the process as file descriptors supporting the read/write
1952 syscalls, it's possible to isolate those applications in
1953 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001954 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001955 and the task is only allowed to execute a few safe syscalls
1956 defined by each seccomp mode.
1957
1958 If unsure, say Y. Only embedded should say N here.
1959
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001960source kernel/Kconfig.hz
1961
1962config KEXEC
1963 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001964 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001965 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001966 kexec is a system call that implements the ability to shutdown your
1967 current kernel, and to start another kernel. It is like a reboot
1968 but it is independent of the system firmware. And like a reboot
1969 you can start any kernel with it, not just Linux.
1970
1971 The name comes from the similarity to the exec system call.
1972
1973 It is an ongoing process to be certain the hardware in a machine
1974 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001975 initially work for you. As of this writing the exact hardware
1976 interface is strongly in flux, so no good recommendation can be
1977 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001978
Vivek Goyal74ca3172014-08-29 15:18:46 -07001979config KEXEC_FILE
1980 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07001981 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07001982 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07001983 depends on X86_64
1984 depends on CRYPTO=y
1985 depends on CRYPTO_SHA256=y
1986 ---help---
1987 This is new version of kexec system call. This system call is
1988 file based and takes file descriptors as system call argument
1989 for kernel and initramfs as opposed to list of segments as
1990 accepted by previous system call.
1991
AKASHI Takahirob799a092018-04-13 15:35:45 -07001992config ARCH_HAS_KEXEC_PURGATORY
1993 def_bool KEXEC_FILE
1994
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001995config KEXEC_VERIFY_SIG
1996 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07001997 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001998 ---help---
1999 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002000 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002001
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002002 In addition to that option, you need to enable signature
2003 verification for the corresponding kernel image type being
2004 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002005
2006config KEXEC_BZIMAGE_VERIFY_SIG
2007 bool "Enable bzImage signature verification support"
2008 depends on KEXEC_VERIFY_SIG
2009 depends on SIGNED_PE_FILE_VERIFICATION
2010 select SYSTEM_TRUSTED_KEYRING
2011 ---help---
2012 Enable bzImage signature verification support.
2013
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002014config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002015 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002016 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002017 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002018 Generate crash dump after being started by kexec.
2019 This should be normally only set in special crash dump kernels
2020 which are loaded in the main kernel with kexec-tools into
2021 a specially reserved region and then later executed after
2022 a crash by kdump/kexec. The crash dump kernel must be compiled
2023 to a memory address not used by the main kernel or BIOS using
2024 PHYSICAL_START, or it must be built as a relocatable image
2025 (CONFIG_RELOCATABLE=y).
2026 For more details see Documentation/kdump/kdump.txt
2027
Huang Ying3ab83522008-07-25 19:45:07 -07002028config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002029 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002030 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002031 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07002032 Jump between original kernel and kexeced kernel and invoke
2033 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002034
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002035config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002036 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002037 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002038 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002039 This gives the physical address where the kernel is loaded.
2040
2041 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2042 bzImage will decompress itself to above physical address and
2043 run from there. Otherwise, bzImage will run from the address where
2044 it has been loaded by the boot loader and will ignore above physical
2045 address.
2046
2047 In normal kdump cases one does not have to set/change this option
2048 as now bzImage can be compiled as a completely relocatable image
2049 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2050 address. This option is mainly useful for the folks who don't want
2051 to use a bzImage for capturing the crash dump and want to use a
2052 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2053 to be specifically compiled to run from a specific memory area
2054 (normally a reserved region) and this option comes handy.
2055
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002056 So if you are using bzImage for capturing the crash dump,
2057 leave the value here unchanged to 0x1000000 and set
2058 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2059 for capturing the crash dump change this value to start of
2060 the reserved region. In other words, it can be set based on
2061 the "X" value as specified in the "crashkernel=YM@XM"
2062 command line boot parameter passed to the panic-ed
2063 kernel. Please take a look at Documentation/kdump/kdump.txt
2064 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002065
2066 Usage of bzImage for capturing the crash dump is recommended as
2067 one does not have to build two kernels. Same kernel can be used
2068 as production kernel and capture kernel. Above option should have
2069 gone away after relocatable bzImage support is introduced. But it
2070 is present because there are users out there who continue to use
2071 vmlinux for dump capture. This option should go away down the
2072 line.
2073
2074 Don't change this unless you know what you are doing.
2075
2076config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002077 bool "Build a relocatable kernel"
2078 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002079 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002080 This builds a kernel image that retains relocation information
2081 so it can be loaded someplace besides the default 1MB.
2082 The relocations tend to make the kernel binary about 10% larger,
2083 but are discarded at runtime.
2084
2085 One use is for the kexec on panic case where the recovery kernel
2086 must live at a different physical address than the primary
2087 kernel.
2088
2089 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2090 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002091 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002092
Kees Cook8ab38202013-10-10 17:18:14 -07002093config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002094 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002095 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002096 default y
Kees Cook8ab38202013-10-10 17:18:14 -07002097 ---help---
Baoquan Hee8581e32016-04-20 13:55:43 -07002098 In support of Kernel Address Space Layout Randomization (KASLR),
2099 this randomizes the physical address at which the kernel image
2100 is decompressed and the virtual address where the kernel
2101 image is mapped, as a security feature that deters exploit
2102 attempts relying on knowledge of the location of kernel
2103 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002104
Kees Cooked9f0072016-05-25 15:45:33 -07002105 On 64-bit, the kernel physical and virtual addresses are
2106 randomized separately. The physical address will be anywhere
2107 between 16MB and the top of physical memory (up to 64TB). The
2108 virtual address will be randomized from 16MB up to 1GB (9 bits
2109 of entropy). Note that this also reduces the memory space
2110 available to kernel modules from 1.5GB to 1GB.
2111
2112 On 32-bit, the kernel physical and virtual addresses are
2113 randomized together. They will be randomized from 16MB up to
2114 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002115
Baoquan Hee8581e32016-04-20 13:55:43 -07002116 Entropy is generated using the RDRAND instruction if it is
2117 supported. If RDTSC is supported, its value is mixed into
2118 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002119 supported, then entropy is read from the i8254 timer. The
2120 usable entropy is limited by the kernel being built using
2121 2GB addressing, and that PHYSICAL_ALIGN must be at a
2122 minimum of 2MB. As a result, only 10 bits of entropy are
2123 theoretically possible, but the implementations are further
2124 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002125
Ingo Molnar6807c842017-04-18 11:08:12 +02002126 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002127
2128# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002129config X86_NEED_RELOCS
2130 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002131 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002132
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002133config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002134 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002135 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002136 range 0x2000 0x1000000 if X86_32
2137 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002138 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002139 This value puts the alignment restrictions on physical address
2140 where kernel is loaded and run from. Kernel is compiled for an
2141 address which meets above alignment restriction.
2142
2143 If bootloader loads the kernel at a non-aligned address and
2144 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2145 address aligned to above value and run from there.
2146
2147 If bootloader loads the kernel at a non-aligned address and
2148 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2149 load address and decompress itself to the address it has been
2150 compiled for and run from there. The address for which kernel is
2151 compiled already meets above alignment restrictions. Hence the
2152 end result is that kernel runs from a physical address meeting
2153 above alignment restrictions.
2154
Kees Cooka0215062013-07-08 09:15:17 -07002155 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2156 this value must be a multiple of 0x200000.
2157
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002158 Don't change this unless you know what you are doing.
2159
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002160config DYNAMIC_MEMORY_LAYOUT
2161 bool
2162 ---help---
2163 This option makes base addresses of vmalloc and vmemmap as well as
2164 __PAGE_OFFSET movable during boot.
2165
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002166config RANDOMIZE_MEMORY
2167 bool "Randomize the kernel memory sections"
2168 depends on X86_64
2169 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002170 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002171 default RANDOMIZE_BASE
2172 ---help---
2173 Randomizes the base virtual address of kernel memory sections
2174 (physical memory mapping, vmalloc & vmemmap). This security feature
2175 makes exploits relying on predictable memory locations less reliable.
2176
2177 The order of allocations remains unchanged. Entropy is generated in
2178 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2179 configuration have in average 30,000 different possible virtual
2180 addresses for each memory section.
2181
Ingo Molnar6807c842017-04-18 11:08:12 +02002182 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002183
Thomas Garnier90397a42016-06-21 17:47:06 -07002184config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2185 hex "Physical memory mapping padding" if EXPERT
2186 depends on RANDOMIZE_MEMORY
2187 default "0xa" if MEMORY_HOTPLUG
2188 default "0x0"
2189 range 0x1 0x40 if MEMORY_HOTPLUG
2190 range 0x0 0x40
2191 ---help---
2192 Define the padding in terabytes added to the existing physical
2193 memory size during kernel memory randomization. It is useful
2194 for memory hotplug support but reduces the entropy available for
2195 address randomization.
2196
2197 If unsure, leave at the default value.
2198
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002199config HOTPLUG_CPU
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002200 bool "Support for hot-pluggable CPUs"
Stephen Rothwell40b31362013-05-21 13:49:35 +10002201 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002202 ---help---
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002203 Say Y here to allow turning CPUs off and on. CPUs can be
2204 controlled through /sys/devices/system/cpu.
2205 ( Note: power management support will enable this option
2206 automatically on SMP systems. )
2207 Say N if you want to disable CPU hotplug.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002208
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002209config BOOTPARAM_HOTPLUG_CPU0
2210 bool "Set default setting of cpu0_hotpluggable"
2211 default n
Kees Cook2c922cd2013-01-22 13:01:19 -08002212 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002213 ---help---
2214 Set whether default state of cpu0_hotpluggable is on or off.
2215
2216 Say Y here to enable CPU0 hotplug by default. If this switch
2217 is turned on, there is no need to give cpu0_hotplug kernel
2218 parameter and the CPU0 hotplug feature is enabled by default.
2219
2220 Please note: there are two known CPU0 dependencies if you want
2221 to enable the CPU0 hotplug feature either by this switch or by
2222 cpu0_hotplug kernel parameter.
2223
2224 First, resume from hibernate or suspend always starts from CPU0.
2225 So hibernate and suspend are prevented if CPU0 is offline.
2226
2227 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2228 offline if any interrupt can not migrate out of CPU0. There may
2229 be other CPU0 dependencies.
2230
2231 Please make sure the dependencies are under your control before
2232 you enable this feature.
2233
2234 Say N if you don't want to enable CPU0 hotplug feature by default.
2235 You still can enable the CPU0 hotplug feature at boot by kernel
2236 parameter cpu0_hotplug.
2237
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002238config DEBUG_HOTPLUG_CPU0
2239 def_bool n
2240 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002241 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002242 ---help---
2243 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2244 soon as possible and boots up userspace with CPU0 offlined. User
2245 can online CPU0 back after boot time.
2246
2247 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2248 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2249 compilation or giving cpu0_hotplug kernel parameter at boot.
2250
2251 If unsure, say N.
2252
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002253config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002254 def_bool n
2255 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002256 depends on COMPAT_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002257 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002258 Certain buggy versions of glibc will crash if they are
2259 presented with a 32-bit vDSO that is not mapped at the address
2260 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002261
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002262 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2263 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2264 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2265 the only released version with the bug, but OpenSUSE 9
2266 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002267
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002268 The symptom of the bug is that everything crashes on startup, saying:
2269 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2270
2271 Saying Y here changes the default value of the vdso32 boot
2272 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2273 This works around the glibc bug but hurts performance.
2274
2275 If unsure, say N: if you are compiling your own kernel, you
2276 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002277
Kees Cook3dc33bd2015-08-12 17:55:19 -07002278choice
2279 prompt "vsyscall table for legacy applications"
2280 depends on X86_64
2281 default LEGACY_VSYSCALL_EMULATE
2282 help
2283 Legacy user code that does not know how to find the vDSO expects
2284 to be able to issue three syscalls by calling fixed addresses in
2285 kernel space. Since this location is not randomized with ASLR,
2286 it can be used to assist security vulnerability exploitation.
2287
2288 This setting can be changed at boot time via the kernel command
Andy Lutomirski076ca272018-03-07 11:12:27 -08002289 line parameter vsyscall=[emulate|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002290
2291 On a system with recent enough glibc (2.14 or newer) and no
2292 static binaries, you can say None without a performance penalty
2293 to improve security.
2294
2295 If unsure, select "Emulate".
2296
Kees Cook3dc33bd2015-08-12 17:55:19 -07002297 config LEGACY_VSYSCALL_EMULATE
2298 bool "Emulate"
2299 help
2300 The kernel traps and emulates calls into the fixed
2301 vsyscall address mapping. This makes the mapping
2302 non-executable, but it still contains known contents,
2303 which could be used in certain rare security vulnerability
2304 exploits. This configuration is recommended when userspace
2305 still uses the vsyscall area.
2306
2307 config LEGACY_VSYSCALL_NONE
2308 bool "None"
2309 help
2310 There will be no vsyscall mapping at all. This will
2311 eliminate any risk of ASLR bypass due to the vsyscall
2312 fixed address mapping. Attempts to use the vsyscalls
2313 will be reported to dmesg, so that either old or
2314 malicious userspace programs can be identified.
2315
2316endchoice
2317
Tim Bird516cbf32008-08-12 12:52:36 -07002318config CMDLINE_BOOL
2319 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002320 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002321 Allow for specifying boot arguments to the kernel at
2322 build time. On some systems (e.g. embedded ones), it is
2323 necessary or convenient to provide some or all of the
2324 kernel boot arguments with the kernel itself (that is,
2325 to not rely on the boot loader to provide them.)
2326
2327 To compile command line arguments into the kernel,
2328 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002329 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002330
2331 Systems with fully functional boot loaders (i.e. non-embedded)
2332 should leave this option set to 'N'.
2333
2334config CMDLINE
2335 string "Built-in kernel command string"
2336 depends on CMDLINE_BOOL
2337 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002338 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002339 Enter arguments here that should be compiled into the kernel
2340 image and used at boot time. If the boot loader provides a
2341 command line at boot time, it is appended to this string to
2342 form the full kernel command line, when the system boots.
2343
2344 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2345 change this behavior.
2346
2347 In most cases, the command line (whether built-in or provided
2348 by the boot loader) should specify the device for the root
2349 file system.
2350
2351config CMDLINE_OVERRIDE
2352 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002353 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002354 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002355 Set this option to 'Y' to have the kernel ignore the boot loader
2356 command line, and use ONLY the built-in command line.
2357
2358 This is used to work around broken boot loaders. This should
2359 be set to 'N' under normal conditions.
2360
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002361config MODIFY_LDT_SYSCALL
2362 bool "Enable the LDT (local descriptor table)" if EXPERT
2363 default y
2364 ---help---
2365 Linux can allow user programs to install a per-process x86
2366 Local Descriptor Table (LDT) using the modify_ldt(2) system
2367 call. This is required to run 16-bit or segmented code such as
2368 DOSEMU or some Wine programs. It is also used by some very old
2369 threading libraries.
2370
2371 Enabling this feature adds a small amount of overhead to
2372 context switches and increases the low-level kernel attack
2373 surface. Disabling it removes the modify_ldt(2) system call.
2374
2375 Saying 'N' here may make sense for embedded or server kernels.
2376
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002377source "kernel/livepatch/Kconfig"
2378
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002379endmenu
2380
Michal Hocko3072e412017-09-08 16:11:39 -07002381config ARCH_HAS_ADD_PAGES
2382 def_bool y
2383 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2384
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002385config ARCH_ENABLE_MEMORY_HOTPLUG
2386 def_bool y
2387 depends on X86_64 || (X86_32 && HIGHMEM)
2388
Gary Hade35551052008-10-31 10:52:03 -07002389config ARCH_ENABLE_MEMORY_HOTREMOVE
2390 def_bool y
2391 depends on MEMORY_HOTPLUG
2392
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002393config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002394 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002395 depends on NUMA
2396
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002397config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2398 def_bool y
2399 depends on X86_64 || X86_PAE
2400
Naoya Horiguchic177c812014-06-04 16:05:35 -07002401config ARCH_ENABLE_HUGEPAGE_MIGRATION
2402 def_bool y
2403 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2404
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002405config ARCH_ENABLE_THP_MIGRATION
2406 def_bool y
2407 depends on X86_64 && TRANSPARENT_HUGEPAGE
2408
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002409menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002410
2411config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002412 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002413 depends on X86_64 && HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002414
2415source "kernel/power/Kconfig"
2416
2417source "drivers/acpi/Kconfig"
2418
Feng Tangefafc8b2009-08-14 15:23:29 -04002419source "drivers/sfi/Kconfig"
2420
Andi Kleena6b68072008-01-30 13:32:49 +01002421config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002422 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002423 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002424
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002425menuconfig APM
2426 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002427 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002428 ---help---
2429 APM is a BIOS specification for saving power using several different
2430 techniques. This is mostly useful for battery powered laptops with
2431 APM compliant BIOSes. If you say Y here, the system time will be
2432 reset after a RESUME operation, the /proc/apm device will provide
2433 battery status information, and user-space programs will receive
2434 notification of APM "events" (e.g. battery status change).
2435
2436 If you select "Y" here, you can disable actual use of the APM
2437 BIOS by passing the "apm=off" option to the kernel at boot time.
2438
2439 Note that the APM support is almost completely disabled for
2440 machines with more than one CPU.
2441
2442 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002443 and more information, read <file:Documentation/power/apm-acpi.txt>
2444 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002445 <http://www.tldp.org/docs.html#howto>.
2446
2447 This driver does not spin down disk drives (see the hdparm(8)
2448 manpage ("man 8 hdparm") for that), and it doesn't turn off
2449 VESA-compliant "green" monitors.
2450
2451 This driver does not support the TI 4000M TravelMate and the ACER
2452 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2453 desktop machines also don't have compliant BIOSes, and this driver
2454 may cause those machines to panic during the boot phase.
2455
2456 Generally, if you don't have a battery in your machine, there isn't
2457 much point in using this driver and you should say N. If you get
2458 random kernel OOPSes or reboots that don't seem to be related to
2459 anything, try disabling/enabling this option (or disabling/enabling
2460 APM in your BIOS).
2461
2462 Some other things you should try when experiencing seemingly random,
2463 "weird" problems:
2464
2465 1) make sure that you have enough swap space and that it is
2466 enabled.
2467 2) pass the "no-hlt" option to the kernel
2468 3) switch on floating point emulation in the kernel and pass
2469 the "no387" option to the kernel
2470 4) pass the "floppy=nodma" option to the kernel
2471 5) pass the "mem=4M" option to the kernel (thereby disabling
2472 all but the first 4 MB of RAM)
2473 6) make sure that the CPU is not over clocked.
2474 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2475 8) disable the cache from your BIOS settings
2476 9) install a fan for the video card or exchange video RAM
2477 10) install a better fan for the CPU
2478 11) exchange RAM chips
2479 12) exchange the motherboard.
2480
2481 To compile this driver as a module, choose M here: the
2482 module will be called apm.
2483
2484if APM
2485
2486config APM_IGNORE_USER_SUSPEND
2487 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002488 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002489 This option will ignore USER SUSPEND requests. On machines with a
2490 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2491 series notebooks, it is necessary to say Y because of a BIOS bug.
2492
2493config APM_DO_ENABLE
2494 bool "Enable PM at boot time"
2495 ---help---
2496 Enable APM features at boot time. From page 36 of the APM BIOS
2497 specification: "When disabled, the APM BIOS does not automatically
2498 power manage devices, enter the Standby State, enter the Suspend
2499 State, or take power saving steps in response to CPU Idle calls."
2500 This driver will make CPU Idle calls when Linux is idle (unless this
2501 feature is turned off -- see "Do CPU IDLE calls", below). This
2502 should always save battery power, but more complicated APM features
2503 will be dependent on your BIOS implementation. You may need to turn
2504 this option off if your computer hangs at boot time when using APM
2505 support, or if it beeps continuously instead of suspending. Turn
2506 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2507 T400CDT. This is off by default since most machines do fine without
2508 this feature.
2509
2510config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002511 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002512 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002513 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002514 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2515 On some machines, this can activate improved power savings, such as
2516 a slowed CPU clock rate, when the machine is idle. These idle calls
2517 are made after the idle loop has run for some length of time (e.g.,
2518 333 mS). On some machines, this will cause a hang at boot time or
2519 whenever the CPU becomes idle. (On machines with more than one CPU,
2520 this option does nothing.)
2521
2522config APM_DISPLAY_BLANK
2523 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002524 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002525 Enable console blanking using the APM. Some laptops can use this to
2526 turn off the LCD backlight when the screen blanker of the Linux
2527 virtual console blanks the screen. Note that this is only used by
2528 the virtual console screen blanker, and won't turn off the backlight
2529 when using the X Window system. This also doesn't have anything to
2530 do with your VESA-compliant power-saving monitor. Further, this
2531 option doesn't work for all laptops -- it might not turn off your
2532 backlight at all, or it might print a lot of errors to the console,
2533 especially if you are using gpm.
2534
2535config APM_ALLOW_INTS
2536 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002537 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002538 Normally we disable external interrupts while we are making calls to
2539 the APM BIOS as a measure to lessen the effects of a badly behaving
2540 BIOS implementation. The BIOS should reenable interrupts if it
2541 needs to. Unfortunately, some BIOSes do not -- especially those in
2542 many of the newer IBM Thinkpads. If you experience hangs when you
2543 suspend, try setting this to Y. Otherwise, say N.
2544
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002545endif # APM
2546
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002547source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002548
2549source "drivers/cpuidle/Kconfig"
2550
Andy Henroid27471fd2008-10-09 11:45:22 -07002551source "drivers/idle/Kconfig"
2552
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002553endmenu
2554
2555
2556menu "Bus options (PCI etc.)"
2557
2558config PCI
Ingo Molnar1ac97012008-05-19 14:10:14 +02002559 bool "PCI support"
Adrian Bunk1c858082008-01-30 13:32:32 +01002560 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002561 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002562 Find out whether you have a PCI motherboard. PCI is the name of a
2563 bus system, i.e. the way the CPU talks to the other stuff inside
2564 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2565 VESA. If you have PCI, say Y, otherwise N.
2566
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002567choice
2568 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002569 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002570 default PCI_GOANY
2571 ---help---
2572 On PCI systems, the BIOS can be used to detect the PCI devices and
2573 determine their configuration. However, some old PCI motherboards
2574 have BIOS bugs and may crash if this is done. Also, some embedded
2575 PCI-based systems don't have any BIOS at all. Linux can also try to
2576 detect the PCI hardware directly without using the BIOS.
2577
2578 With this option, you can specify how Linux should detect the
2579 PCI devices. If you choose "BIOS", the BIOS will be used,
2580 if you choose "Direct", the BIOS won't be used, and if you
2581 choose "MMConfig", then PCI Express MMCONFIG will be used.
2582 If you choose "Any", the kernel will try MMCONFIG, then the
2583 direct access method and falls back to the BIOS if that doesn't
2584 work. If unsure, go with the default, which is "Any".
2585
2586config PCI_GOBIOS
2587 bool "BIOS"
2588
2589config PCI_GOMMCONFIG
2590 bool "MMConfig"
2591
2592config PCI_GODIRECT
2593 bool "Direct"
2594
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002595config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002596 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002597 depends on OLPC
2598
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002599config PCI_GOANY
2600 bool "Any"
2601
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002602endchoice
2603
2604config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002605 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002606 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002607
2608# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2609config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002610 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002611 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002612
2613config PCI_MMCONFIG
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002614 bool "Support mmconfig PCI config space access" if X86_64
2615 default y
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002616 depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002617 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002618
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002619config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002620 def_bool y
2621 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002622
Alex Nixonb5401a92010-03-18 16:31:34 -04002623config PCI_XEN
2624 def_bool y
2625 depends on PCI && XEN
2626 select SWIOTLB_XEN
2627
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002628config PCI_DOMAINS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002629 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002630 depends on PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002631
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002632config MMCONF_FAM10H
2633 def_bool y
2634 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002635
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002636config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002637 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002638 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002639 help
2640 Read the PCI windows out of the CNB20LE host bridge. This allows
2641 PCI hotplug to work on systems with the CNB20LE chipset which do
2642 not have ACPI.
2643
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002644 There's no public spec for this chipset, and this functionality
2645 is known to be incomplete.
2646
2647 You should say N unless you know you need this.
2648
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002649source "drivers/pci/Kconfig"
2650
William Breathitt Gray3a495512016-05-27 18:08:27 -04002651config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002652 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002653 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002654 Expose ISA bus device drivers and options available for selection and
2655 configuration. Enable this option if your target machine has an ISA
2656 bus. ISA is an older system, displaced by PCI and newer bus
2657 architectures -- if your target machine is modern, it probably does
2658 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002659
2660 If unsure, say N.
2661
David Rientjes1c00f012011-03-22 16:34:59 -07002662# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002663config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002664 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2665 default y
2666 help
2667 Enables ISA-style DMA support for devices requiring such controllers.
2668 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002669
Linus Torvalds51e68d02016-05-21 10:25:19 -07002670if X86_32
2671
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002672config ISA
2673 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002674 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002675 Find out whether you have ISA slots on your motherboard. ISA is the
2676 name of a bus system, i.e. the way the CPU talks to the other stuff
2677 inside your box. Other bus systems are PCI, EISA, MicroChannel
2678 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2679 newer boards don't support it. If you have ISA, say Y, otherwise N.
2680
2681config EISA
2682 bool "EISA support"
2683 depends on ISA
2684 ---help---
2685 The Extended Industry Standard Architecture (EISA) bus was
2686 developed as an open alternative to the IBM MicroChannel bus.
2687
2688 The EISA bus provided some of the features of the IBM MicroChannel
2689 bus while maintaining backward compatibility with cards made for
2690 the older ISA bus. The EISA bus saw limited use between 1988 and
2691 1995 when it was made obsolete by the PCI bus.
2692
2693 Say Y here if you are building a kernel for an EISA-based machine.
2694
2695 Otherwise, say N.
2696
2697source "drivers/eisa/Kconfig"
2698
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002699config SCx200
2700 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002701 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002702 This provides basic support for National Semiconductor's
2703 (now AMD's) Geode processors. The driver probes for the
2704 PCI-IDs of several on-chip devices, so its a good dependency
2705 for other scx200_* drivers.
2706
2707 If compiled as a module, the driver is named scx200.
2708
2709config SCx200HR_TIMER
2710 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002711 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002712 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002713 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002714 This driver provides a clocksource built upon the on-chip
2715 27MHz high-resolution timer. Its also a workaround for
2716 NSC Geode SC-1100's buggy TSC, which loses time when the
2717 processor goes idle (as is done by the scheduler). The
2718 other workaround is idle=poll boot option.
2719
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002720config OLPC
2721 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002722 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002723 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002724 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002725 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002726 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002727 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002728 Add support for detecting the unique features of the OLPC
2729 XO hardware.
2730
Daniel Drakea3128582011-06-25 17:34:10 +01002731config OLPC_XO1_PM
2732 bool "OLPC XO-1 Power Management"
Daniel Drake97c4cb72011-06-25 17:34:11 +01002733 depends on OLPC && MFD_CS5535 && PM_SLEEP
Daniel Drakea3128582011-06-25 17:34:10 +01002734 select MFD_CORE
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002735 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002736 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002737
Daniel Drakecfee9592011-06-25 17:34:17 +01002738config OLPC_XO1_RTC
2739 bool "OLPC XO-1 Real Time Clock"
2740 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2741 ---help---
2742 Add support for the XO-1 real time clock, which can be used as a
2743 programmable wakeup source.
2744
Daniel Drake7feda8e2011-06-25 17:34:12 +01002745config OLPC_XO1_SCI
2746 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002747 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002748 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002749 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002750 ---help---
2751 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002752 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002753 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002754 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002755 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002756 - AC adapter status updates
2757 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002758
Daniel Drakea0f30f52011-06-25 17:34:18 +01002759config OLPC_XO15_SCI
2760 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002761 depends on OLPC && ACPI
2762 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002763 ---help---
2764 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2765 - EC-driven system wakeups
2766 - AC adapter status updates
2767 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002768
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002769config ALIX
2770 bool "PCEngines ALIX System Support (LED setup)"
2771 select GPIOLIB
2772 ---help---
2773 This option enables system support for the PCEngines ALIX.
2774 At present this just sets up LEDs for GPIO control on
2775 ALIX2/3/6 boards. However, other system specific setup should
2776 get added here.
2777
2778 Note: You must still enable the drivers for GPIO and LED support
2779 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2780
2781 Note: You have to set alix.force=1 for boards with Award BIOS.
2782
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002783config NET5501
2784 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2785 select GPIOLIB
2786 ---help---
2787 This option enables system support for the Soekris Engineering net5501.
2788
Philip A. Prindeville31970592012-01-14 01:45:39 -07002789config GEOS
2790 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2791 select GPIOLIB
2792 depends on DMI
2793 ---help---
2794 This option enables system support for the Traverse Technologies GEOS.
2795
Vivien Didelot7d029122013-01-04 16:18:14 -05002796config TS5500
2797 bool "Technologic Systems TS-5500 platform support"
2798 depends on MELAN
2799 select CHECK_SIGNATURE
2800 select NEW_LEDS
2801 select LEDS_CLASS
2802 ---help---
2803 This option enables system support for the Technologic Systems TS-5500.
2804
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002805endif # X86_32
2806
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002807config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002808 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002809 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002810
2811source "drivers/pcmcia/Kconfig"
2812
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002813config RAPIDIO
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002814 tristate "RapidIO support"
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002815 depends on PCI
2816 default n
2817 help
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002818 If enabled this option will include drivers and the core
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002819 infrastructure code to support RapidIO interconnect devices.
2820
2821source "drivers/rapidio/Kconfig"
2822
David Herrmanne3263ab2013-08-02 14:05:22 +02002823config X86_SYSFB
2824 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2825 help
2826 Firmwares often provide initial graphics framebuffers so the BIOS,
2827 bootloader or kernel can show basic video-output during boot for
2828 user-guidance and debugging. Historically, x86 used the VESA BIOS
2829 Extensions and EFI-framebuffers for this, which are mostly limited
2830 to x86.
2831 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2832 framebuffers so the new generic system-framebuffer drivers can be
2833 used on x86. If the framebuffer is not compatible with the generic
2834 modes, it is adverticed as fallback platform framebuffer so legacy
2835 drivers like efifb, vesafb and uvesafb can pick it up.
2836 If this option is not selected, all system framebuffers are always
2837 marked as fallback platform framebuffers as usual.
2838
2839 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2840 not be able to pick up generic system framebuffers if this option
2841 is selected. You are highly encouraged to enable simplefb as
2842 replacement if you select this option. simplefb can correctly deal
2843 with generic system framebuffers. But you should still keep vesafb
2844 and others enabled as fallback if a system framebuffer is
2845 incompatible with simplefb.
2846
2847 If unsure, say Y.
2848
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002849endmenu
2850
2851
2852menu "Executable file formats / Emulations"
2853
2854source "fs/Kconfig.binfmt"
2855
2856config IA32_EMULATION
2857 bool "IA32 Emulation"
2858 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002859 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002860 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002861 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002862 select COMPAT_OLD_SIGACTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002863 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002864 Include code to run legacy 32-bit programs under a
2865 64-bit kernel. You should likely turn this on, unless you're
2866 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002867
2868config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002869 tristate "IA32 a.out support"
2870 depends on IA32_EMULATION
2871 ---help---
2872 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002873
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002874config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002875 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002876 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002877 ---help---
2878 Include code to run binaries for the x32 native 32-bit ABI
2879 for 64-bit processors. An x32 process gets access to the
2880 full 64-bit register file and wide data path while leaving
2881 pointers at 32 bits for smaller memory footprint.
2882
2883 You will need a recent binutils (2.22 or later) with
2884 elf32_x86_64 support enabled to compile a kernel with this
2885 option set.
2886
Ingo Molnar953fee12016-11-15 10:22:52 +01002887config COMPAT_32
2888 def_bool y
2889 depends on IA32_EMULATION || X86_32
2890 select HAVE_UID16
2891 select OLD_SIGSUSPEND3
2892
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002893config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002894 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002895 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002896
Jan Beulich3120e252012-09-10 12:41:45 +01002897if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002898config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002899 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002900
2901config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002902 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002903 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002904endif
David Howellsee009e4a02011-03-07 15:06:20 +00002905
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002906endmenu
2907
2908
Keith Packarde5beae12008-11-03 18:21:45 +01002909config HAVE_ATOMIC_IOMAP
2910 def_bool y
2911 depends on X86_32
2912
Alessandro Rubini4692d772012-04-04 19:39:58 +02002913config X86_DEV_DMA_OPS
2914 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002915 depends on X86_64 || STA2X11
Alessandro Rubini4692d772012-04-04 19:39:58 +02002916
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002917config X86_DMA_REMAP
2918 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002919 depends on STA2X11
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002920
Kirill A. Shutemove5855132017-06-06 14:31:20 +03002921config HAVE_GENERIC_GUP
2922 def_bool y
2923
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002924source "net/Kconfig"
2925
2926source "drivers/Kconfig"
2927
2928source "drivers/firmware/Kconfig"
2929
2930source "fs/Kconfig"
2931
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002932source "arch/x86/Kconfig.debug"
2933
2934source "security/Kconfig"
2935
2936source "crypto/Kconfig"
2937
Avi Kivityedf88412007-12-16 11:02:48 +02002938source "arch/x86/kvm/Kconfig"
2939
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002940source "lib/Kconfig"