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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
Masahiro Yamada104daea2018-05-28 18:21:40 +09004 bool "64-bit kernel" if "$(ARCH)" = "x86"
5 default "$(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
Laurent Dufour3010a5e2018-06-07 17:06:08 -070063 select ARCH_HAS_PTE_SPECIAL
Kees Cook39208aa2017-09-02 13:09:46 -070064 select ARCH_HAS_REFCOUNT
Dan Williams0aed55a2017-05-29 12:22:50 -070065 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Dan Williams87803562018-05-03 17:06:31 -070066 select ARCH_HAS_UACCESS_MCSAFE if X86_64
Daniel Borkmannd2852a22017-02-21 16:09:33 +010067 select ARCH_HAS_SET_MEMORY
Ingo Molnar6471b822015-06-03 10:00:13 +020068 select ARCH_HAS_SG_CHAIN
Laura Abbottad21fc42017-02-06 16:31:57 -080069 select ARCH_HAS_STRICT_KERNEL_RWX
70 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050071 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Andrey Ryabininc6d30852016-01-20 15:00:55 -080072 select ARCH_HAS_UBSAN_SANITIZE_ALL
Oliver O'Halloran65f7d042017-06-28 11:32:31 +100073 select ARCH_HAS_ZONE_DEVICE if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020074 select ARCH_HAVE_NMI_SAFE_CMPXCHG
75 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040076 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080077 select ARCH_MIGHT_HAVE_PC_SERIO
Ingo Molnar6471b822015-06-03 10:00:13 +020078 select ARCH_SUPPORTS_ATOMIC_RMW
Ingo Molnar6471b822015-06-03 10:00:13 +020079 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
80 select ARCH_USE_BUILTIN_BSWAP
Ingo Molnar6471b822015-06-03 10:00:13 +020081 select ARCH_USE_QUEUED_RWLOCKS
82 select ARCH_USE_QUEUED_SPINLOCKS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -070083 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Ingo Molnarc763ea22016-11-15 10:26:39 +010084 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Huang Ying38d8b4e2017-07-06 15:37:18 -070085 select ARCH_WANTS_THP_SWAP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020086 select BUILDTIME_EXTABLE_SORT
87 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +020088 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
89 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +020090 select DCACHE_WORD_ACCESS
Christoph Hellwigfec777c2018-03-19 11:38:15 +010091 select DMA_DIRECT_OPS
Linus Torvalds45471cd2015-06-24 19:52:06 -070092 select EDAC_ATOMIC_SCRUB
93 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +020094 select GENERIC_CLOCKEVENTS
95 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
96 select GENERIC_CLOCKEVENTS_MIN_ADJUST
97 select GENERIC_CMOS_UPDATE
98 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +010099 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +0200100 select GENERIC_EARLY_IOREMAP
101 select GENERIC_FIND_FIRST_BIT
102 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +0200103 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +0200104 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +0200105 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200106 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200107 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200108 select GENERIC_IRQ_SHOW
109 select GENERIC_PENDING_IRQ if SMP
110 select GENERIC_SMP_IDLE_THREAD
111 select GENERIC_STRNCPY_FROM_USER
112 select GENERIC_STRNLEN_USER
113 select GENERIC_TIME_VSYSCALL
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200114 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200115 select HAVE_ACPI_APEI if ACPI
116 select HAVE_ACPI_APEI_NMI if ACPI
117 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200118 select HAVE_ARCH_AUDITSYSCALL
119 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
120 select HAVE_ARCH_JUMP_LABEL
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800121 select HAVE_ARCH_KASAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200122 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800123 select HAVE_ARCH_MMAP_RND_BITS if MMU
124 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300125 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ingo Molnar6471b822015-06-03 10:00:13 +0200126 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700127 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Ingo Molnar6471b822015-06-03 10:00:13 +0200128 select HAVE_ARCH_TRACEHOOK
129 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Matthew Wilcoxa00cc7d2017-02-24 14:57:02 -0800130 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
Andy Lutomirskie37e43a2016-08-11 02:35:23 -0700131 select HAVE_ARCH_VMAP_STACK if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100132 select HAVE_ARCH_WITHIN_STACK_FRAMES
Ingo Molnar6471b822015-06-03 10:00:13 +0200133 select HAVE_CC_STACKPROTECTOR
134 select HAVE_CMPXCHG_DOUBLE
135 select HAVE_CMPXCHG_LOCAL
136 select HAVE_CONTEXT_TRACKING if X86_64
Josh Triplettc1bd55f2015-06-30 15:00:00 -0700137 select HAVE_COPY_THREAD_TLS
Ingo Molnar6471b822015-06-03 10:00:13 +0200138 select HAVE_C_RECORDMCOUNT
139 select HAVE_DEBUG_KMEMLEAK
140 select HAVE_DEBUG_STACKOVERFLOW
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700141 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400142 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900143 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Wang YanQing03f57812018-05-03 14:10:43 +0800144 select HAVE_EBPF_JIT
Johannes Berg58340a02008-07-25 01:45:33 -0700145 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Jiri Slaby5f56a5d2016-05-20 17:00:16 -0700146 select HAVE_EXIT_THREAD
Steven Rostedt (VMware)644e0e82017-03-23 10:33:52 -0400147 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
Ingo Molnar6471b822015-06-03 10:00:13 +0200148 select HAVE_FTRACE_MCOUNT_RECORD
Ingo Molnar6471b822015-06-03 10:00:13 +0200149 select HAVE_FUNCTION_GRAPH_TRACER
150 select HAVE_FUNCTION_TRACER
Emese Revfy6b90bd42016-05-24 00:09:38 +0200151 select HAVE_GCC_PLUGINS
K.Prasad0067f122009-06-01 23:43:57 +0530152 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200153 select HAVE_IDE
154 select HAVE_IOREMAP_PROT
155 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
156 select HAVE_IRQ_TIME_ACCOUNTING
157 select HAVE_KERNEL_BZIP2
158 select HAVE_KERNEL_GZIP
159 select HAVE_KERNEL_LZ4
160 select HAVE_KERNEL_LZMA
161 select HAVE_KERNEL_LZO
162 select HAVE_KERNEL_XZ
163 select HAVE_KPROBES
164 select HAVE_KPROBES_ON_FTRACE
Masami Hiramatsu540adea2018-01-13 02:55:03 +0900165 select HAVE_FUNCTION_ERROR_INJECTION
Ingo Molnar6471b822015-06-03 10:00:13 +0200166 select HAVE_KRETPROBES
167 select HAVE_KVM
168 select HAVE_LIVEPATCH if X86_64
169 select HAVE_MEMBLOCK
170 select HAVE_MEMBLOCK_NODE_MAP
Frederic Weisbecker01027522010-04-11 18:55:56 +0200171 select HAVE_MIXED_BREAKPOINTS_REGS
Josh Poimboeufee9f8fc2017-07-24 18:36:57 -0500172 select HAVE_MOD_ARCH_SPECIFIC
Petr Mladek42a0bb32016-05-20 17:00:33 -0700173 select HAVE_NMI
Ingo Molnar6471b822015-06-03 10:00:13 +0200174 select HAVE_OPROFILE
175 select HAVE_OPTPROBES
176 select HAVE_PCSPKR_PLATFORM
177 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200178 select HAVE_PERF_EVENTS_NMI
Nicholas Piggin92e5aae2017-08-18 15:15:51 -0700179 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
Jiri Olsac5e63192012-08-07 15:20:36 +0200180 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200181 select HAVE_PERF_USER_STACK_DUMP
Vitaly Kuznetsov9e52fc22017-08-28 10:22:51 +0200182 select HAVE_RCU_TABLE_FREE
Ingo Molnar6471b822015-06-03 10:00:13 +0200183 select HAVE_REGS_AND_STACK_ACCESS_API
Josh Poimboeuf11af8472017-10-13 15:02:00 -0500184 select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
Ingo Molnarc763ea22016-11-15 10:26:39 +0100185 select HAVE_STACK_VALIDATION if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200186 select HAVE_SYSCALL_TRACEPOINTS
Ingo Molnar6471b822015-06-03 10:00:13 +0200187 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300188 select HAVE_USER_RETURN_NOTIFIER
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100189 select IRQ_FORCED_THREADING
Christoph Hellwig86596f02018-04-05 09:44:52 +0200190 select NEED_SG_DMA_LENGTH
Thomas Gleixnerdf65c1b2017-03-16 22:50:07 +0100191 select PCI_LOCKLESS_CONFIG
Ingo Molnar6471b822015-06-03 10:00:13 +0200192 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500193 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200194 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200195 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500196 select SRCU
Ingo Molnar6471b822015-06-03 10:00:13 +0200197 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700198 select THREAD_INFO_IN_TASK
Ingo Molnar6471b822015-06-03 10:00:13 +0200199 select USER_STACKTRACE_SUPPORT
200 select VIRT_TO_BUS
Ingo Molnar6471b822015-06-03 10:00:13 +0200201 select X86_FEATURE_NAMES if PROC_FS
Balbir Singh7d8330a2008-02-10 12:46:28 +0530202
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200203config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100204 def_bool y
205 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200206
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700207config OUTPUT_FORMAT
208 string
209 default "elf32-i386" if X86_32
210 default "elf64-x86-64" if X86_64
211
Sam Ravnborg73531902008-05-25 23:03:18 +0200212config ARCH_DEFCONFIG
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200213 string
Sam Ravnborg73531902008-05-25 23:03:18 +0200214 default "arch/x86/configs/i386_defconfig" if X86_32
215 default "arch/x86/configs/x86_64_defconfig" if X86_64
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200216
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100217config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100218 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100219
220config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100221 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100222
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100223config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100224 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100225
Daniel Cashman9e08f572016-01-14 15:20:06 -0800226config ARCH_MMAP_RND_BITS_MIN
227 default 28 if 64BIT
228 default 8
229
230config ARCH_MMAP_RND_BITS_MAX
231 default 32 if 64BIT
232 default 16
233
234config ARCH_MMAP_RND_COMPAT_BITS_MIN
235 default 8
236
237config ARCH_MMAP_RND_COMPAT_BITS_MAX
238 default 16
239
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100240config SBUS
241 bool
242
243config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100244 def_bool y
245 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100246
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100247config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100248 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100249 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000250 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
251
252config GENERIC_BUG_RELATIVE_POINTERS
253 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100254
255config GENERIC_HWEIGHT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100256 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100257
258config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100259 def_bool y
260 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100261
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100262config RWSEM_XCHGADD_ALGORITHM
Jan Beulich3120e252012-09-10 12:41:45 +0100263 def_bool y
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100264
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100265config GENERIC_CALIBRATE_DELAY
266 def_bool y
267
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800268config ARCH_HAS_CPU_RELAX
269 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100270
Pekka Enberg1b27d052008-04-28 02:12:22 -0700271config ARCH_HAS_CACHE_LINE_SIZE
272 def_bool y
273
Dave Hansen316d0972018-04-20 15:20:28 -0700274config ARCH_HAS_FILTER_PGPROT
275 def_bool y
276
Mike Travisdd5af902008-01-30 13:33:32 +0100277config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900278 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100279
Tejun Heo08fc4582009-08-14 15:00:49 +0900280config NEED_PER_CPU_EMBED_FIRST_CHUNK
281 def_bool y
282
283config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900284 def_bool y
285
Johannes Berg801e4062007-12-08 02:12:39 +0100286config ARCH_HIBERNATION_POSSIBLE
287 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100288
Johannes Bergf4cb5702007-12-08 02:14:00 +0100289config ARCH_SUSPEND_POSSIBLE
290 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100291
Steve Cappercfe28c52013-04-29 14:29:48 +0100292config ARCH_WANT_HUGE_PMD_SHARE
293 def_bool y
294
Steve Capper53313b22013-04-30 08:03:42 +0100295config ARCH_WANT_GENERAL_HUGETLB
296 def_bool y
297
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100298config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000299 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100300
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100301config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000302 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100303
Ingo Molnar765c68b2008-04-09 11:03:37 +0200304config ARCH_SUPPORTS_OPTIMIZED_INLINING
305 def_bool y
306
Akinobu Mita6a11f752009-03-31 15:23:17 -0700307config ARCH_SUPPORTS_DEBUG_PAGEALLOC
308 def_bool y
309
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300310config KASAN_SHADOW_OFFSET
311 hex
312 depends on KASAN
313 default 0xdffffc0000000000
314
Shane Wang69575d32009-09-01 18:25:07 -0700315config HAVE_INTEL_TXT
316 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700317 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700318
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100319config X86_32_SMP
320 def_bool y
321 depends on X86_32 && SMP
322
323config X86_64_SMP
324 def_bool y
325 depends on X86_64 && SMP
326
Tejun Heoccbeed32009-02-09 22:17:40 +0900327config X86_32_LAZY_GS
328 def_bool y
Kees Cook2bc2f682018-02-06 15:37:41 -0800329 depends on X86_32 && CC_STACKPROTECTOR_NONE
Tejun Heoccbeed32009-02-09 22:17:40 +0900330
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530331config ARCH_SUPPORTS_UPROBES
332 def_bool y
333
Rob Herringd20642f2014-04-18 17:19:54 -0500334config FIX_EARLYCON_MEM
335 def_bool y
336
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700337config PGTABLE_LEVELS
338 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300339 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700340 default 4 if X86_64
341 default 3 if X86_PAE
342 default 2
343
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100344source "init/Kconfig"
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700345source "kernel/Kconfig.freezer"
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100346
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100347menu "Processor type and features"
348
Randy Dunlap5ee71532012-01-16 11:57:18 -0800349config ZONE_DMA
350 bool "DMA memory allocation support" if EXPERT
351 default y
352 help
353 DMA memory allocation support allows devices with less than 32-bit
354 addressing to allocate within the first 16MB of address space.
355 Disable if no such devices will be used.
356
357 If unsure, say Y.
358
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100359config SMP
360 bool "Symmetric multi-processing support"
361 ---help---
362 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800363 a system with only one CPU, say N. If you have a system with more
364 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100365
Robert Graffham4a474152014-01-23 15:55:29 -0800366 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100367 machines, but will use only one CPU of a multiprocessor machine. If
368 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800369 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100370 will run faster if you say N here.
371
372 Note that if you say Y here and choose architecture "586" or
373 "Pentium" under "Processor family", the kernel will not work on 486
374 architectures. Similarly, multiprocessor kernels for the "PPro"
375 architecture may not work on all Pentium based boards.
376
377 People using multiprocessor machines who say Y here should also say
378 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
379 Management" code will be disabled if you say Y here.
380
Paul Bolle395cf962011-08-15 02:02:26 +0200381 See also <file:Documentation/x86/i386/IO-APIC.txt>,
Benjamin Petersonc9525a32017-05-20 17:20:16 -0700382 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100383 <http://www.tldp.org/docs.html#howto>.
384
385 If you don't know what to do here, say N.
386
Josh Triplett9def39be2013-10-30 08:09:45 -0700387config X86_FEATURE_NAMES
388 bool "Processor feature human-readable names" if EMBEDDED
389 default y
390 ---help---
391 This option compiles in a table of x86 feature bits and corresponding
392 names. This is required to support /proc/cpuinfo and a few kernel
393 messages. You can disable this to save space, at the expense of
394 making those few kernel messages show numeric feature bits instead.
395
396 If in doubt, say Y.
397
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800398config X86_X2APIC
399 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200400 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800401 ---help---
402 This enables x2apic support on CPUs that have this feature.
403
404 This allows 32-bit apic IDs (so it can support very large systems),
405 and accesses the local apic via MSRs not via mmio.
406
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800407 If you don't know what to do here, say N.
408
Yinghai Lu6695c852008-06-19 12:13:09 -0700409config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700410 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000411 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200412 depends on X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100413 ---help---
Yinghai Lu6695c852008-06-19 12:13:09 -0700414 For old smp systems that do not have proper acpi support. Newer systems
415 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700416
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000417config GOLDFISH
418 def_bool y
419 depends on X86_GOLDFISH
420
David Woodhouse76b04382018-01-11 21:46:25 +0000421config RETPOLINE
422 bool "Avoid speculative indirect branches in kernel"
423 default y
Peter Zijlstrad5028ba2018-02-06 09:46:13 +0100424 select STACK_VALIDATION if HAVE_STACK_VALIDATION
David Woodhouse76b04382018-01-11 21:46:25 +0000425 help
426 Compile kernel with the retpoline compiler options to guard against
427 kernel-to-user data leaks by avoiding speculative indirect
428 branches. Requires a compiler with -mindirect-branch=thunk-extern
429 support for full protection. The kernel may run slower.
430
431 Without compiler support, at least indirect branches in assembler
432 code are eliminated. Since this includes the syscall entry path,
433 it is not entirely pointless.
434
Vikas Shivappaf01d7d512017-07-25 14:14:22 -0700435config INTEL_RDT
436 bool "Intel Resource Director Technology support"
Fenghua Yu78e99b42016-10-22 06:19:53 -0700437 default n
438 depends on X86 && CPU_SUP_INTEL
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100439 select KERNFS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700440 help
Vikas Shivappaf01d7d512017-07-25 14:14:22 -0700441 Select to enable resource allocation and monitoring which are
442 sub-features of Intel Resource Director Technology(RDT). More
443 information about RDT can be found in the Intel x86
444 Architecture Software Developer Manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700445
446 Say N if unsure.
447
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800448if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800449config X86_BIGSMP
450 bool "Support for big SMP systems with more than 8 CPUs"
451 depends on SMP
452 ---help---
453 This option is needed for the systems that have more than 8 CPUs
454
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800455config X86_EXTENDED_PLATFORM
456 bool "Support for extended (non-PC) x86 platforms"
457 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100458 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100459 If you disable this option then the kernel will only support
460 standard PC platforms. (which covers the vast majority of
461 systems out there.)
462
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800463 If you enable this option then you'll be able to select support
464 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100465 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800466 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800467 RDC R-321x SoC
468 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200469 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200470 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100471
472 If you have one of these systems, or if you want to build a
473 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800474endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100475
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800476if X86_64
477config X86_EXTENDED_PLATFORM
478 bool "Support for extended (non-PC) x86 platforms"
479 default y
480 ---help---
481 If you disable this option then the kernel will only support
482 standard PC platforms. (which covers the vast majority of
483 systems out there.)
484
485 If you enable this option then you'll be able to select support
486 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800487 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800488 ScaleMP vSMP
489 SGI Ultraviolet
490
491 If you have one of these systems, or if you want to build a
492 generic distribution kernel, say Y here - otherwise say N.
493endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800494# This is an alphabetically sorted list of 64 bit extended platforms
495# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800496config X86_NUMACHIP
497 bool "Numascale NumaChip"
498 depends on X86_64
499 depends on X86_EXTENDED_PLATFORM
500 depends on NUMA
501 depends on SMP
502 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700503 depends on PCI_MMCONFIG
Steffen Persvold44b111b52011-12-06 00:07:26 +0800504 ---help---
505 Adds support for Numascale NumaChip large-SMP systems. Needed to
506 enable more than ~168 cores.
507 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100508
Ingo Molnar6a485652009-01-27 18:29:13 +0100509config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800510 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100511 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100512 select PARAVIRT
513 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800514 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300515 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100516 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100517 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
518 supposed to run on these EM64T-based machines. Only choose this option
519 if you have one of these machines.
520
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800521config X86_UV
522 bool "SGI Ultraviolet"
523 depends on X86_64
524 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500525 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800526 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700527 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200528 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800529 ---help---
530 This option is needed in order to support SGI Ultraviolet systems.
531 If you don't have one of these, you should say N here.
532
533# Following is an alphabetically sorted list of 32 bit extended platforms
534# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100535
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000536config X86_GOLDFISH
537 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100538 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000539 ---help---
540 Enable support for the Goldfish virtual platform used primarily
541 for Android development. Unless you are building for the Android
542 Goldfish emulator say N here.
543
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800544config X86_INTEL_CE
545 bool "CE4100 TV platform"
546 depends on PCI
547 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800548 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800549 depends on X86_32
550 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800551 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100552 select OF
553 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800554 ---help---
555 Select for the Intel CE media processor (CE4100) SOC.
556 This option compiles in support for the CE4100 SOC for settop
557 boxes and media devices.
558
David Cohen4cb9b002013-12-16 17:37:26 -0800559config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100560 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100561 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800562 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000563 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200564 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000565 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000566 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800567 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000568 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000569 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000570 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000571 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000572 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800573 Select to build a kernel capable of supporting Intel MID (Mobile
574 Internet Device) platform systems which do not have the PCI legacy
575 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000576
David Cohen4cb9b002013-12-16 17:37:26 -0800577 Intel MID platforms are based on an Intel processor and chipset which
578 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100579
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000580config X86_INTEL_QUARK
581 bool "Intel Quark platform support"
582 depends on X86_32
583 depends on X86_EXTENDED_PLATFORM
584 depends on X86_PLATFORM_DEVICES
585 depends on X86_TSC
586 depends on PCI
587 depends on PCI_GOANY
588 depends on X86_IO_APIC
589 select IOSF_MBI
590 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200591 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000592 ---help---
593 Select to include support for Quark X1000 SoC.
594 Say Y here if you have a Quark based system such as the Arduino
595 compatible Intel Galileo.
596
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000597config X86_INTEL_LPSS
598 bool "Intel Low Power Subsystem Support"
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100599 depends on X86 && ACPI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000600 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300601 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100602 select IOSF_MBI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000603 ---help---
604 Select to build support for Intel Low Power Subsystem such as
605 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300606 things like clock tree (common clock framework) and pincontrol
607 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000608
Ken Xue92082a82015-02-06 08:27:51 +0800609config X86_AMD_PLATFORM_DEVICE
610 bool "AMD ACPI2Platform devices support"
611 depends on ACPI
612 select COMMON_CLK
613 select PINCTRL
614 ---help---
615 Select to interpret AMD specific ACPI device to platform device
616 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
617 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
618 implemented under PINCTRL subsystem.
619
David E. Boxced3ce72014-09-17 22:13:50 -0700620config IOSF_MBI
621 tristate "Intel SoC IOSF Sideband support for SoC platforms"
622 depends on PCI
623 ---help---
624 This option enables sideband register access support for Intel SoC
625 platforms. On these platforms the IOSF sideband is used in lieu of
626 MSR's for some register accesses, mostly but not limited to thermal
627 and power. Drivers may query the availability of this device to
628 determine if they need the sideband in order to work on these
629 platforms. The sideband is available on the following SoC products.
630 This list is not meant to be exclusive.
631 - BayTrail
632 - Braswell
633 - Quark
634
635 You should say Y if you are running a kernel on one of these SoC's.
636
David E. Boxed2226b2014-09-17 22:13:51 -0700637config IOSF_MBI_DEBUG
638 bool "Enable IOSF sideband access through debugfs"
639 depends on IOSF_MBI && DEBUG_FS
640 ---help---
641 Select this option to expose the IOSF sideband access registers (MCR,
642 MDR, MCRX) through debugfs to write and read register information from
643 different units on the SoC. This is most useful for obtaining device
644 state information for debug and analysis. As this is a general access
645 mechanism, users of this option would have specific knowledge of the
646 device they want to access.
647
648 If you don't require the option or are in doubt, say N.
649
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800650config X86_RDC321X
651 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100652 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800653 depends on X86_EXTENDED_PLATFORM
654 select M486
655 select X86_REBOOTFIXUPS
656 ---help---
657 This option is needed for RDC R-321x system-on-chip, also known
658 as R-8610-(G).
659 If you don't have one of these chips, you should say N here.
660
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100661config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100662 bool "Support non-standard 32-bit SMP architectures"
663 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800664 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100665 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800666 This option compiles in the bigsmp and STA2X11 default
667 subarchitectures. It is intended for a generic binary
668 kernel. If you select them all, kernel will probe it one by
669 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700670
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800671# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700672
Linus Torvaldsd949f362009-09-26 09:35:07 -0700673config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100674 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700675 # MCE code calls memory_failure():
676 depends on X86_MCE
677 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700678 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
679 depends on X86_64 || !SPARSEMEM
680 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700681
Alessandro Rubini83125a32012-04-04 19:40:21 +0200682config STA2X11
683 bool "STA2X11 Companion Chip Support"
684 depends on X86_32_NON_STANDARD && PCI
Christoph Hellwigb6e05472018-03-19 11:38:24 +0100685 select ARCH_HAS_PHYS_TO_DMA
Alessandro Rubini83125a32012-04-04 19:40:21 +0200686 select X86_DEV_DMA_OPS
687 select X86_DMA_REMAP
688 select SWIOTLB
689 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200690 select GPIOLIB
Alessandro Rubini83125a32012-04-04 19:40:21 +0200691 default n
692 ---help---
693 This adds support for boards based on the STA2X11 IO-Hub,
694 a.k.a. "ConneXt". The chip is used in place of the standard
695 PC chipset, so all "standard" peripherals are missing. If this
696 option is selected the kernel will still be able to boot on
697 standard PC machines.
698
Shérab82148d12010-09-25 06:06:57 +0200699config X86_32_IRIS
700 tristate "Eurobraille/Iris poweroff module"
701 depends on X86_32
702 ---help---
703 The Iris machines from EuroBraille do not have APM or ACPI support
704 to shut themselves down properly. A special I/O sequence is
705 needed to do so, which is what this module does at
706 kernel shutdown.
707
708 This is only for Iris machines from EuroBraille.
709
710 If unused, say N.
711
Ingo Molnarae1e9132008-11-11 09:05:16 +0100712config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100713 def_bool y
714 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800715 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100716 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100717 Calculate simpler /proc/<PID>/wchan values. If this option
718 is disabled then wchan values will recurse back to the
719 caller function. This provides more accurate wchan values,
720 at the expense of slightly more scheduling overhead.
721
722 If in doubt, say "Y".
723
Borislav Petkov6276a072013-03-04 21:20:21 +0100724menuconfig HYPERVISOR_GUEST
725 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100726 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100727 Say Y here to enable options for running Linux under various hyper-
728 visors. This option enables basic hypervisor detection and platform
729 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100730
Borislav Petkov6276a072013-03-04 21:20:21 +0100731 If you say N, all options in this submenu will be skipped and
732 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100733
Borislav Petkov6276a072013-03-04 21:20:21 +0100734if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100735
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100736config PARAVIRT
737 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100738 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100739 This changes the kernel so it can modify itself when it is run
740 under a hypervisor, potentially improving performance significantly
741 over full virtualization. However, when run without a hypervisor
742 the kernel is theoretically slower and slightly larger.
743
Borislav Petkov6276a072013-03-04 21:20:21 +0100744config PARAVIRT_DEBUG
745 bool "paravirt-ops debugging"
746 depends on PARAVIRT && DEBUG_KERNEL
747 ---help---
748 Enable to debug paravirt_ops internals. Specifically, BUG if
749 a paravirt_op is missing when it is called.
750
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700751config PARAVIRT_SPINLOCKS
752 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700753 depends on PARAVIRT && SMP
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700754 ---help---
755 Paravirtualized spinlocks allow a pvops backend to replace the
756 spinlock implementation with something virtualization-friendly
757 (for example, block the virtual CPU rather than spinning).
758
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530759 It has a minimal impact on native kernels and gives a nice performance
760 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700761
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530762 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700763
Waiman Long45e898b2015-11-09 19:09:25 -0500764config QUEUED_LOCK_STAT
765 bool "Paravirt queued spinlock statistics"
Peter Zijlstracfd89832016-05-18 20:43:02 +0200766 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
Waiman Long45e898b2015-11-09 19:09:25 -0500767 ---help---
768 Enable the collection of statistical data on the slowpath
769 behavior of paravirtualized queued spinlocks and report
770 them on debugfs.
771
Borislav Petkov6276a072013-03-04 21:20:21 +0100772source "arch/x86/xen/Kconfig"
773
774config KVM_GUEST
775 bool "KVM Guest support (including kvmclock)"
776 depends on PARAVIRT
777 select PARAVIRT_CLOCK
778 default y
779 ---help---
780 This option enables various optimizations for running under the KVM
781 hypervisor. It includes a paravirtualized clock, so that instead
782 of relying on a PIT (or probably other) emulation by the
783 underlying device model, the host provides the guest with
784 timing infrastructure such as time of day, and system time
785
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530786config KVM_DEBUG_FS
787 bool "Enable debug information for KVM Guests in debugfs"
788 depends on KVM_GUEST && DEBUG_FS
789 default n
790 ---help---
791 This option enables collection of various statistics for KVM guest.
792 Statistics are displayed in debugfs filesystem. Enabling this option
793 may incur significant overhead.
794
Borislav Petkov6276a072013-03-04 21:20:21 +0100795config PARAVIRT_TIME_ACCOUNTING
796 bool "Paravirtual steal time accounting"
797 depends on PARAVIRT
798 default n
799 ---help---
800 Select this option to enable fine granularity task steal time
801 accounting. Time spent executing other tasks in parallel with
802 the current vCPU is discounted from the vCPU power. To account for
803 that, there can be a small performance impact.
804
805 If in doubt, say N here.
806
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200807config PARAVIRT_CLOCK
808 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200809
Jan Kiszka4a362602017-11-27 09:11:46 +0100810config JAILHOUSE_GUEST
811 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100812 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100813 select X86_PM_TIMER
Jan Kiszka4a362602017-11-27 09:11:46 +0100814 ---help---
815 This option allows to run Linux as guest in a Jailhouse non-root
816 cell. You can leave this option disabled if you only want to start
817 Jailhouse and run Linux afterwards in the root cell.
818
Borislav Petkov6276a072013-03-04 21:20:21 +0100819endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400820
Yinghai Lu08677212010-02-10 01:20:20 -0800821config NO_BOOTMEM
Yinghai Lu774ea0b2010-08-25 13:39:18 -0700822 def_bool y
Yinghai Lu08677212010-02-10 01:20:20 -0800823
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100824source "arch/x86/Kconfig.cpu"
825
826config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100827 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100828 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100829 ---help---
830 Use the IA-PC HPET (High Precision Event Timer) to manage
831 time in preference to the PIT and RTC, if a HPET is
832 present.
833 HPET is the next generation timer replacing legacy 8254s.
834 The HPET provides a stable time base on SMP
835 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200836 as it is off-chip. The interface used is documented
837 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100838
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100839 You can safely choose Y here. However, HPET will only be
840 activated if the platform and the BIOS support this feature.
841 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100842
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100843 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100844
845config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100846 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800847 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100848
Jacob Panbb24c472009-09-02 07:37:17 -0700849config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000850 def_bool y if X86_INTEL_MID
851 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100852 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000853 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700854 help
855 APB timer is the replacement for 8254, HPET on X86 MID platforms.
856 The APBT provides a stable time base on SMP
857 systems, unlike the TSC, but it is more expensive to access,
858 as it is off-chip. APB timers are always running regardless of CPU
859 C states, they are used as per CPU clockevent device when possible.
860
David Rientjes6a108a12011-01-20 14:44:16 -0800861# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100862# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700863config DMI
864 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800865 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800866 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100867 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700868 Enabled scanning of DMI to identify machine quirks. Say Y
869 here unless you have verified that your setup is not
870 affected by entries in the DMI blacklist. Required by PNP
871 BIOS code.
872
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100873config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700874 bool "Old AMD GART IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200875 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100876 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200877 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100878 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200879 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
880 GART based hardware IOMMUs.
881
882 The GART supports full DMA access for devices with 32-bit access
883 limitations, on systems with more than 3 GB. This is usually needed
884 for USB, sound, many IDE/SATA chipsets and some other devices.
885
886 Newer systems typically have a modern AMD IOMMU, supported via
887 the CONFIG_AMD_IOMMU=y config option.
888
889 In normal configurations this driver is only active when needed:
890 there's more than 3 GB of memory and the system contains a
891 32-bit limited device.
892
893 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100894
895config CALGARY_IOMMU
896 bool "IBM Calgary IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200897 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100898 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700899 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100900 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100901 Support for hardware IOMMUs in IBM's xSeries x366 and x460
902 systems. Needed to run systems with more than 3GB of memory
903 properly with 32-bit PCI devices that do not support DAC
904 (Double Address Cycle). Calgary also supports bus level
905 isolation, where all DMAs pass through the IOMMU. This
906 prevents them from going anywhere except their intended
907 destination. This catches hard-to-find kernel bugs and
908 mis-behaving drivers and devices that do not use the DMA-API
909 properly to set up their DMA buffers. The IOMMU can be
910 turned off at boot time with the iommu=off parameter.
911 Normally the kernel will make the right choice by itself.
912 If unsure, say Y.
913
914config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100915 def_bool y
916 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100917 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100918 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100919 Should Calgary be enabled by default? if you choose 'y', Calgary
920 will be used (if it exists). If you choose 'n', Calgary will not be
921 used even if it exists. If you choose 'n' and would like to use
922 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
923 If unsure, say Y.
924
Mike Travis1184dc22008-05-12 21:21:12 +0200925config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200926 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700927 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800928 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100929 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200930 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200931 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100932
Ingo Molnaraec64872018-02-10 12:36:29 +0100933#
934# The maximum number of CPUs supported:
935#
936# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
937# and which can be configured interactively in the
938# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
939#
940# The ranges are different on 32-bit and 64-bit kernels, depending on
941# hardware capabilities and scalability features of the kernel.
942#
943# ( If MAXSMP is enabled we just use the highest possible value and disable
944# interactive configuration. )
945#
946
947config NR_CPUS_RANGE_BEGIN
948 int
949 default NR_CPUS_RANGE_END if MAXSMP
950 default 1 if !SMP
951 default 2
952
953config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800954 int
955 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100956 default 64 if SMP && X86_BIGSMP
957 default 8 if SMP && !X86_BIGSMP
958 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800959
Ingo Molnaraec64872018-02-10 12:36:29 +0100960config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800961 int
962 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100963 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
964 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
965 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800966
Ingo Molnaraec64872018-02-10 12:36:29 +0100967config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800968 int
969 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100970 default 32 if X86_BIGSMP
971 default 8 if SMP
972 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800973
Ingo Molnaraec64872018-02-10 12:36:29 +0100974config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800975 int
976 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100977 default 8192 if MAXSMP
978 default 64 if SMP
979 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800980
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100981config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800982 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +0100983 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
984 default NR_CPUS_DEFAULT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100985 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100986 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500987 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +0300988 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100989 minimum value which makes sense is 2.
990
Ingo Molnaraec64872018-02-10 12:36:29 +0100991 This is purely to save memory: each supported CPU adds about 8KB
992 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100993
994config SCHED_SMT
995 bool "SMT (Hyperthreading) scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +0200996 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100997 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100998 SMT scheduler support improves the CPU scheduler's decision making
999 when dealing with Intel Pentium 4 chips with HyperThreading at a
1000 cost of slightly increased overhead in some places. If unsure say
1001 N here.
1002
1003config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001004 def_bool y
1005 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001006 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001007 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001008 Multi-core scheduler support improves the CPU scheduler's decision
1009 making when dealing with multi-core CPU chips at a cost of slightly
1010 increased overhead in some places. If unsure say N here.
1011
Tim Chende966cf2016-11-29 10:43:27 -08001012config SCHED_MC_PRIO
1013 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001014 depends on SCHED_MC && CPU_SUP_INTEL
1015 select X86_INTEL_PSTATE
1016 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001017 default y
Tim Chen5e76b2a2016-11-22 12:23:55 -08001018 ---help---
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001019 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1020 core ordering determined at manufacturing time, which allows
1021 certain cores to reach higher turbo frequencies (when running
1022 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001023
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001024 Enabling this kernel feature teaches the scheduler about
1025 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1026 scheduler's CPU selection logic accordingly, so that higher
1027 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001028
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001029 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001030
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001031 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001032
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001033source "kernel/Kconfig.preempt"
1034
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001035config UP_LATE_INIT
1036 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +01001037 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001038
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001039config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001040 bool "Local APIC support on uniprocessors" if !PCI_MSI
1041 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001042 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001043 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001044 A local APIC (Advanced Programmable Interrupt Controller) is an
1045 integrated interrupt controller in the CPU. If you have a single-CPU
1046 system which has a processor with a local APIC, you can say Y here to
1047 enable and use it. If you say Y here even though your machine doesn't
1048 have a local APIC, then the kernel will still run with no slowdown at
1049 all. The local APIC supports CPU-generated self-interrupts (timer,
1050 performance counters), and the NMI watchdog which detects hard
1051 lockups.
1052
1053config X86_UP_IOAPIC
1054 bool "IO-APIC support on uniprocessors"
1055 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001056 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001057 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1058 SMP-capable replacement for PC-style interrupt controllers. Most
1059 SMP systems and many recent uniprocessor systems have one.
1060
1061 If you have a single-CPU system with an IO-APIC, you can say Y here
1062 to use it. If you say Y here even though your machine doesn't have
1063 an IO-APIC, then the kernel will still run with no slowdown at all.
1064
1065config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001066 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001067 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001068 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001069 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001070
1071config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001072 def_bool y
1073 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001074
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001075config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1076 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001077 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001078 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001079 This option enables a workaround that fixes a source of
1080 spurious interrupts. This is recommended when threaded
1081 interrupt handling is used on systems where the generation of
1082 superfluous "boot interrupts" cannot be disabled.
1083
1084 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1085 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1086 kernel does during interrupt handling). On chipsets where this
1087 boot IRQ generation cannot be disabled, this workaround keeps
1088 the original IRQ line masked so that only the equivalent "boot
1089 IRQ" is delivered to the CPUs. The workaround also tells the
1090 kernel to set up the IRQ handler on the boot IRQ line. In this
1091 way only one interrupt is delivered to the kernel. Otherwise
1092 the spurious second interrupt may cause the kernel to bring
1093 down (vital) interrupt lines.
1094
1095 Only affects "broken" chipsets. Interrupt sharing may be
1096 increased on these systems.
1097
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001098config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001099 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001100 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001101 default y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001102 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +02001103 Machine Check support allows the processor to notify the
1104 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001105 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001106 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001107
Tony Luck5de97c92017-03-27 11:33:03 +02001108config X86_MCELOG_LEGACY
1109 bool "Support for deprecated /dev/mcelog character device"
1110 depends on X86_MCE
1111 ---help---
1112 Enable support for /dev/mcelog which is needed by the old mcelog
1113 userspace logging daemon. Consider switching to the new generation
1114 rasdaemon solution.
1115
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001116config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001117 def_bool y
1118 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001119 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001120 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001121 Additional support for intel specific MCE features such as
1122 the thermal monitor.
1123
1124config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001125 def_bool y
1126 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001127 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001128 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001129 Additional support for AMD specific MCE features such as
1130 the DRAM Error Threshold.
1131
Andi Kleen4efc0672009-04-28 19:07:31 +02001132config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001133 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001134 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001135 ---help---
1136 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001137 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001138 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001139
Andi Kleenb2762682009-02-12 13:49:31 +01001140config X86_MCE_THRESHOLD
1141 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001142 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001143
Andi Kleenea149b32009-04-29 19:31:00 +02001144config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001145 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001146 tristate "Machine check injector support"
1147 ---help---
1148 Provide support for injecting machine checks for testing purposes.
1149 If you don't know what a machine check is and you don't do kernel
1150 QA it is safe to say n.
1151
Andi Kleen4efc0672009-04-28 19:07:31 +02001152config X86_THERMAL_VECTOR
1153 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001154 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001155
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001156source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001157
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001158config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001159 bool "Legacy VM86 support"
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001160 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001161 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001162 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001163 This option allows user programs to put the CPU into V8086
1164 mode, which is an 80286-era approximation of 16-bit real mode.
1165
1166 Some very old versions of X and/or vbetool require this option
1167 for user mode setting. Similarly, DOSEMU will use it if
1168 available to accelerate real mode DOS programs. However, any
1169 recent version of DOSEMU, X, or vbetool should be fully
1170 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001171 fall back to software emulation. Nevertheless, if you are using
1172 a 16-bit DOS program where 16-bit performance matters, vm86
1173 mode might be faster than emulation and you might want to
1174 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001175
Ingo Molnar1e642812015-09-05 08:58:10 +02001176 Note that any app that works on a 64-bit kernel is unlikely to
1177 need this option, as 64-bit kernels don't, and can't, support
1178 V8086 mode. This option is also unrelated to 16-bit protected
1179 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001180
Ingo Molnar1e642812015-09-05 08:58:10 +02001181 Enabling this option increases the complexity of the kernel
1182 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001183
Ingo Molnar1e642812015-09-05 08:58:10 +02001184 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001185
1186config VM86
1187 bool
1188 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001189
1190config X86_16BIT
1191 bool "Enable support for 16-bit segments" if EXPERT
1192 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001193 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001194 ---help---
1195 This option is required by programs like Wine to run 16-bit
1196 protected mode legacy code on x86 processors. Disabling
1197 this option saves about 300 bytes on i386, or around 6K text
1198 plus 16K runtime memory on x86-64,
1199
1200config X86_ESPFIX32
1201 def_bool y
1202 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001203
H. Peter Anvin197725d2014-05-04 10:00:49 -07001204config X86_ESPFIX64
1205 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001206 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001207
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001208config X86_VSYSCALL_EMULATION
1209 bool "Enable vsyscall emulation" if EXPERT
1210 default y
1211 depends on X86_64
1212 ---help---
1213 This enables emulation of the legacy vsyscall page. Disabling
1214 it is roughly equivalent to booting with vsyscall=none, except
1215 that it will also disable the helpful warning if a program
1216 tries to use a vsyscall. With this option set to N, offending
1217 programs will just segfault, citing addresses of the form
1218 0xffffffffff600?00.
1219
1220 This option is required by many programs built before 2013, and
1221 care should be used even with newer programs if set to N.
1222
1223 Disabling this option saves about 7K of kernel size and
1224 possibly 4K of additional runtime pagetable memory.
1225
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001226config TOSHIBA
1227 tristate "Toshiba Laptop support"
1228 depends on X86_32
1229 ---help---
1230 This adds a driver to safely access the System Management Mode of
1231 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1232 not work on models with a Phoenix BIOS. The System Management Mode
1233 is used to set the BIOS and power saving options on Toshiba portables.
1234
1235 For information on utilities to make use of this driver see the
1236 Toshiba Linux utilities web site at:
1237 <http://www.buzzard.org.uk/toshiba/>.
1238
1239 Say Y if you intend to run this kernel on a Toshiba portable.
1240 Say N otherwise.
1241
1242config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001243 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001244 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001245 select SENSORS_DELL_SMM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001246 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001247 This option enables legacy /proc/i8k userspace interface in hwmon
1248 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1249 temperature and allows controlling fan speeds of Dell laptops via
1250 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1251 it reports also power and hotkey status. For fan speed control is
1252 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001253
Pali Rohár039ae582015-05-14 13:16:37 +02001254 Say Y if you intend to run this kernel on old Dell laptops or want to
1255 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001256 Say N otherwise.
1257
1258config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001259 bool "Enable X86 board specific fixups for reboot"
1260 depends on X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001261 ---help---
1262 This enables chipset and/or board specific fixups to be done
1263 in order to get reboot to work correctly. This is only needed on
1264 some combinations of hardware and BIOS. The symptom, for which
1265 this config is intended, is when reboot ends with a stalled/hung
1266 system.
1267
1268 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001269 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001270
1271 Say Y if you want to enable the fixup. Currently, it's safe to
1272 enable this option even if you don't need it.
1273 Say N otherwise.
1274
1275config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001276 bool "CPU microcode loading support"
1277 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001278 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001279 select FW_LOADER
1280 ---help---
1281 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001282 Intel and AMD processors. The Intel support is for the IA32 family,
1283 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1284 AMD support is for families 0x10 and later. You will obviously need
1285 the actual microcode binary data itself which is not shipped with
1286 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001287
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001288 The preferred method to load microcode from a detached initrd is described
Jaak Ristioja1897a962018-02-09 11:22:16 +02001289 in Documentation/x86/microcode.txt. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001290 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1291 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001292
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001293 In addition, you can build the microcode into the kernel. For that you
1294 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1295 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001296
Peter Oruba8d86f392008-07-28 18:44:21 +02001297config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001298 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001299 depends on MICROCODE
1300 default MICROCODE
1301 select FW_LOADER
1302 ---help---
1303 This options enables microcode patch loading support for Intel
1304 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001305
Alanb8989db2014-01-20 18:01:56 +00001306 For the current Intel microcode data package go to
1307 <https://downloadcenter.intel.com> and search for
1308 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001309
Peter Oruba80cc9f12008-07-28 18:44:22 +02001310config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001311 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001312 depends on MICROCODE
1313 select FW_LOADER
1314 ---help---
1315 If you select this option, microcode patch loading support for AMD
1316 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001317
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001318config MICROCODE_OLD_INTERFACE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001319 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001320 depends on MICROCODE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001321
1322config X86_MSR
1323 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001324 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001325 This device gives privileged processes access to the x86
1326 Model-Specific Registers (MSRs). It is a character device with
1327 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1328 MSR accesses are directed to a specific CPU on multi-processor
1329 systems.
1330
1331config X86_CPUID
1332 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001333 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001334 This device gives processes access to the x86 CPUID instruction to
1335 be executed on a specific processor. It is a character device
1336 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1337 /dev/cpu/31/cpuid.
1338
1339choice
1340 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001341 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001342 depends on X86_32
1343
1344config NOHIGHMEM
1345 bool "off"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001346 ---help---
1347 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1348 However, the address space of 32-bit x86 processors is only 4
1349 Gigabytes large. That means that, if you have a large amount of
1350 physical memory, not all of it can be "permanently mapped" by the
1351 kernel. The physical memory that's not permanently mapped is called
1352 "high memory".
1353
1354 If you are compiling a kernel which will never run on a machine with
1355 more than 1 Gigabyte total physical RAM, answer "off" here (default
1356 choice and suitable for most users). This will result in a "3GB/1GB"
1357 split: 3GB are mapped so that each process sees a 3GB virtual memory
1358 space and the remaining part of the 4GB virtual memory space is used
1359 by the kernel to permanently map as much physical memory as
1360 possible.
1361
1362 If the machine has between 1 and 4 Gigabytes physical RAM, then
1363 answer "4GB" here.
1364
1365 If more than 4 Gigabytes is used then answer "64GB" here. This
1366 selection turns Intel PAE (Physical Address Extension) mode on.
1367 PAE implements 3-level paging on IA32 processors. PAE is fully
1368 supported by Linux, PAE mode is implemented on all recent Intel
1369 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1370 then the kernel will not boot on CPUs that don't support PAE!
1371
1372 The actual amount of total physical memory will either be
1373 auto detected or can be forced by using a kernel command line option
1374 such as "mem=256M". (Try "man bootparam" or see the documentation of
1375 your boot loader (lilo or loadlin) about how to pass options to the
1376 kernel at boot time.)
1377
1378 If unsure, say "off".
1379
1380config HIGHMEM4G
1381 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001382 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001383 Select this if you have a 32-bit processor and between 1 and 4
1384 gigabytes of physical RAM.
1385
1386config HIGHMEM64G
1387 bool "64GB"
Matthew Whitehead69b8d3f2018-02-15 11:54:55 -05001388 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001389 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001390 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001391 Select this if you have a 32-bit processor and more than 4
1392 gigabytes of physical RAM.
1393
1394endchoice
1395
1396choice
David Rientjes6a108a12011-01-20 14:44:16 -08001397 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001398 default VMSPLIT_3G
1399 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001400 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001401 Select the desired split between kernel and user memory.
1402
1403 If the address range available to the kernel is less than the
1404 physical memory installed, the remaining memory will be available
1405 as "high memory". Accessing high memory is a little more costly
1406 than low memory, as it needs to be mapped into the kernel first.
1407 Note that increasing the kernel address space limits the range
1408 available to user programs, making the address space there
1409 tighter. Selecting anything other than the default 3G/1G split
1410 will also likely make your kernel incompatible with binary-only
1411 kernel modules.
1412
1413 If you are not absolutely sure what you are doing, leave this
1414 option alone!
1415
1416 config VMSPLIT_3G
1417 bool "3G/1G user/kernel split"
1418 config VMSPLIT_3G_OPT
1419 depends on !X86_PAE
1420 bool "3G/1G user/kernel split (for full 1G low memory)"
1421 config VMSPLIT_2G
1422 bool "2G/2G user/kernel split"
1423 config VMSPLIT_2G_OPT
1424 depends on !X86_PAE
1425 bool "2G/2G user/kernel split (for full 2G low memory)"
1426 config VMSPLIT_1G
1427 bool "1G/3G user/kernel split"
1428endchoice
1429
1430config PAGE_OFFSET
1431 hex
1432 default 0xB0000000 if VMSPLIT_3G_OPT
1433 default 0x80000000 if VMSPLIT_2G
1434 default 0x78000000 if VMSPLIT_2G_OPT
1435 default 0x40000000 if VMSPLIT_1G
1436 default 0xC0000000
1437 depends on X86_32
1438
1439config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001440 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001441 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001442
1443config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001444 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001445 depends on X86_32 && !HIGHMEM4G
Christoph Hellwigd4a451d2018-04-03 16:24:20 +02001446 select PHYS_ADDR_T_64BIT
Christian Melki9d99c712015-10-05 17:31:33 +02001447 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001448 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001449 PAE is required for NX support, and furthermore enables
1450 larger swapspace support for non-overcommit purposes. It
1451 has the cost of more pagetable lookup overhead, and also
1452 consumes more pagetable space per process.
1453
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001454config X86_5LEVEL
1455 bool "Enable 5-level page tables support"
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001456 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001457 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001458 depends on X86_64
1459 ---help---
1460 5-level paging enables access to larger address space:
1461 upto 128 PiB of virtual address space and 4 PiB of
1462 physical address space.
1463
1464 It will be supported by future Intel CPUs.
1465
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001466 A kernel with the option enabled can be booted on machines that
1467 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001468
1469 See Documentation/x86/x86_64/5level-paging.txt for more
1470 information.
1471
1472 Say N if unsure.
1473
Ingo Molnar10971ab2015-03-05 08:18:23 +01001474config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001475 def_bool y
Levin, Alexander (Sasha Levin)4675ff02017-11-15 17:36:02 -08001476 depends on X86_64 && !DEBUG_PAGEALLOC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001477 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001478 Certain kernel features effectively disable kernel
1479 linear 1 GB mappings (even if the CPU otherwise
1480 supports them), so don't confuse the user by printing
1481 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001482
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001483config ARCH_HAS_MEM_ENCRYPT
1484 def_bool y
1485
1486config AMD_MEM_ENCRYPT
1487 bool "AMD Secure Memory Encryption (SME) support"
1488 depends on X86_64 && CPU_SUP_AMD
1489 ---help---
1490 Say yes to enable support for the encryption of system memory.
1491 This requires an AMD processor that supports Secure Memory
1492 Encryption (SME).
1493
1494config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1495 bool "Activate AMD Secure Memory Encryption (SME) by default"
1496 default y
1497 depends on AMD_MEM_ENCRYPT
1498 ---help---
1499 Say yes to have system memory encrypted by default if running on
1500 an AMD processor that supports Secure Memory Encryption (SME).
1501
1502 If set to Y, then the encryption of system memory can be
1503 deactivated with the mem_encrypt=off command line option.
1504
1505 If set to N, then the encryption of system memory can be
1506 activated with the mem_encrypt=on command line option.
1507
Tom Lendackyf88a68f2017-07-17 16:10:09 -05001508config ARCH_USE_MEMREMAP_PROT
1509 def_bool y
1510 depends on AMD_MEM_ENCRYPT
1511
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001512# Common NUMA Features
1513config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001514 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001515 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001516 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1517 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001518 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001519 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001520
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001521 The kernel will try to allocate memory used by a CPU on the
1522 local memory controller of the CPU and add some more
1523 NUMA awareness to the kernel.
1524
Ingo Molnarc280ea52008-11-08 13:29:45 +01001525 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001526 (or later), AMD Opteron, or EM64T NUMA.
1527
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001528 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001529 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001530
1531 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001532
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001533config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001534 def_bool y
1535 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001536 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001537 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001538 Enable AMD NUMA node topology detection. You should say Y here if
1539 you have a multi processor AMD system. This uses an old method to
1540 read the NUMA configuration directly from the builtin Northbridge
1541 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1542 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001543
1544config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001545 def_bool y
1546 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001547 depends on X86_64 && NUMA && ACPI && PCI
1548 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001549 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001550 Enable ACPI SRAT based node topology detection.
1551
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001552# Some NUMA nodes have memory ranges that span
1553# other nodes. Even though a pfn is valid and
1554# between a node's start and end pfns, it may not
1555# reside on that node. See memmap_init_zone()
1556# for details.
1557config NODES_SPAN_OTHER_NODES
1558 def_bool y
1559 depends on X86_64_ACPI_NUMA
1560
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001561config NUMA_EMU
1562 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001563 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001564 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001565 Enable NUMA emulation. A flat machine will be split
1566 into virtual nodes when booted with "numa=fake=N", where N is the
1567 number of nodes. This is only useful for debugging.
1568
1569config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001570 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001571 range 1 10
1572 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001573 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001574 default "3"
1575 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001576 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001577 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001578 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001579
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001580config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001581 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001582 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001583
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001584config ARCH_FLATMEM_ENABLE
1585 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001586 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001587
1588config ARCH_DISCONTIGMEM_ENABLE
1589 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001590 depends on NUMA && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001591
1592config ARCH_DISCONTIGMEM_DEFAULT
1593 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001594 depends on NUMA && X86_32
1595
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001596config ARCH_SPARSEMEM_ENABLE
1597 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001598 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001599 select SPARSEMEM_STATIC if X86_32
1600 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1601
Tejun Heo3b166512011-04-01 11:15:12 +02001602config ARCH_SPARSEMEM_DEFAULT
1603 def_bool y
1604 depends on X86_64
1605
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001606config ARCH_SELECT_MEMORY_MODEL
1607 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001608 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001609
1610config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001611 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001612 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001613 help
1614 This option enables a sysfs memory/probe interface for testing.
1615 See Documentation/memory-hotplug.txt for more information.
1616 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001617
Tejun Heo3b166512011-04-01 11:15:12 +02001618config ARCH_PROC_KCORE_TEXT
1619 def_bool y
1620 depends on X86_64 && PROC_KCORE
1621
Avi Kivitya29815a2010-01-10 16:28:09 +02001622config ILLEGAL_POINTER_VALUE
1623 hex
1624 default 0 if X86_32
1625 default 0xdead000000000000 if X86_64
1626
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001627source "mm/Kconfig"
1628
Dan Williams7a678322015-08-19 00:34:34 -04001629config X86_PMEM_LEGACY_DEVICE
1630 bool
1631
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001632config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001633 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001634 depends on PHYS_ADDR_T_64BIT
1635 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001636 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001637 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001638 help
1639 Treat memory marked using the non-standard e820 type of 12 as used
1640 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1641 The kernel will offer these regions to the 'pmem' driver so
1642 they can be used for persistent storage.
1643
1644 Say Y if unsure.
1645
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001646config HIGHPTE
1647 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001648 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001649 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001650 The VM uses one page table entry for each page of physical memory.
1651 For systems with a lot of RAM, this can be wasteful of precious
1652 low memory. Setting this option will put user-space page table
1653 entries in high memory.
1654
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001655config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001656 bool "Check for low memory corruption"
1657 ---help---
1658 Periodically check for memory corruption in low memory, which
1659 is suspected to be caused by BIOS. Even when enabled in the
1660 configuration, it is disabled at runtime. Enable it by
1661 setting "memory_corruption_check=1" on the kernel command
1662 line. By default it scans the low 64k of memory every 60
1663 seconds; see the memory_corruption_check_size and
1664 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001665 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001666
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001667 When enabled with the default parameters, this option has
1668 almost no overhead, as it reserves a relatively small amount
1669 of memory and scans it infrequently. It both detects corruption
1670 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001671
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001672 It is, however, intended as a diagnostic tool; if repeatable
1673 BIOS-originated corruption always affects the same memory,
1674 you can use memmap= to prevent the kernel from using that
1675 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001676
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001677config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001678 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001679 depends on X86_CHECK_BIOS_CORRUPTION
1680 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001681 ---help---
1682 Set whether the default state of memory_corruption_check is
1683 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001684
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001685config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001686 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1687 default 64
1688 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001689 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001690 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001691
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001692 The first page contains BIOS data structures that the kernel
1693 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001694
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001695 By default we reserve the first 64K of physical RAM, as a
1696 number of BIOSes are known to corrupt that memory range
1697 during events such as suspend/resume or monitor cable
1698 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001699
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001700 You can set this to 4 if you are absolutely sure that you
1701 trust the BIOS to get all its memory reservations and usages
1702 right. If you know your BIOS have problems beyond the
1703 default 64K area, you can set this to 640 to avoid using the
1704 entire low memory range.
1705
1706 If you have doubts about the BIOS (e.g. suspend/resume does
1707 not work or there's kernel crashes after certain hardware
1708 hotplug events) then you might want to enable
1709 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1710 typical corruption patterns.
1711
1712 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001713
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001714config MATH_EMULATION
1715 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001716 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001717 prompt "Math emulation" if X86_32
1718 ---help---
1719 Linux can emulate a math coprocessor (used for floating point
1720 operations) if you don't have one. 486DX and Pentium processors have
1721 a math coprocessor built in, 486SX and 386 do not, unless you added
1722 a 487DX or 387, respectively. (The messages during boot time can
1723 give you some hints here ["man dmesg"].) Everyone needs either a
1724 coprocessor or this emulation.
1725
1726 If you don't have a math coprocessor, you need to say Y here; if you
1727 say Y here even though you have a coprocessor, the coprocessor will
1728 be used nevertheless. (This behavior can be changed with the kernel
1729 command line option "no387", which comes handy if your coprocessor
1730 is broken. Try "man bootparam" or see the documentation of your boot
1731 loader (lilo or loadlin) about how to pass options to the kernel at
1732 boot time.) This means that it is a good idea to say Y here if you
1733 intend to use this kernel on different machines.
1734
1735 More information about the internals of the Linux math coprocessor
1736 emulation can be found in <file:arch/x86/math-emu/README>.
1737
1738 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1739 kernel, it won't hurt.
1740
1741config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001742 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001743 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001744 ---help---
1745 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1746 the Memory Type Range Registers (MTRRs) may be used to control
1747 processor access to memory ranges. This is most useful if you have
1748 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1749 allows bus write transfers to be combined into a larger transfer
1750 before bursting over the PCI/AGP bus. This can increase performance
1751 of image write operations 2.5 times or more. Saying Y here creates a
1752 /proc/mtrr file which may be used to manipulate your processor's
1753 MTRRs. Typically the X server should use this.
1754
1755 This code has a reasonably generic interface so that similar
1756 control registers on other processors can be easily supported
1757 as well:
1758
1759 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1760 Registers (ARRs) which provide a similar functionality to MTRRs. For
1761 these, the ARRs are used to emulate the MTRRs.
1762 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1763 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1764 write-combining. All of these processors are supported by this code
1765 and it makes sense to say Y here if you have one of them.
1766
1767 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1768 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1769 can lead to all sorts of problems, so it's good to say Y here.
1770
1771 You can safely say Y even if your machine doesn't have MTRRs, you'll
1772 just add about 9 KB to your kernel.
1773
Randy Dunlap7225e752008-07-26 17:54:22 -07001774 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001775
Yinghai Lu95ffa242008-04-29 03:52:33 -07001776config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001777 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001778 prompt "MTRR cleanup support"
1779 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001780 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001781 Convert MTRR layout from continuous to discrete, so X drivers can
1782 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001783
Thomas Gleixneraba37282008-07-15 14:48:48 +02001784 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001785 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001786 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001787
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001788 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001789
1790config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001791 int "MTRR cleanup enable value (0-1)"
1792 range 0 1
1793 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001794 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001795 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001796 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001797
Yinghai Lu12031a62008-05-02 02:40:22 -07001798config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1799 int "MTRR cleanup spare reg num (0-7)"
1800 range 0 7
1801 default "1"
1802 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001803 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001804 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001805 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001806
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001807config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001808 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001809 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001810 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001811 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001812 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001813
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001814 PATs are the modern equivalents of MTRRs and are much more
1815 flexible than MTRRs.
1816
1817 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001818 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001819
1820 If unsure, say Y.
1821
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001822config ARCH_USES_PG_UNCACHED
1823 def_bool y
1824 depends on X86_PAT
1825
H. Peter Anvin628c6242011-07-31 13:59:29 -07001826config ARCH_RANDOM
1827 def_bool y
1828 prompt "x86 architectural random number generator" if EXPERT
1829 ---help---
1830 Enable the x86 architectural RDRAND instruction
1831 (Intel Bull Mountain technology) to generate random numbers.
1832 If supported, this is a high bandwidth, cryptographically
1833 secure hardware random number generator.
1834
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001835config X86_SMAP
1836 def_bool y
1837 prompt "Supervisor Mode Access Prevention" if EXPERT
1838 ---help---
1839 Supervisor Mode Access Prevention (SMAP) is a security
1840 feature in newer Intel processors. There is a small
1841 performance cost if this enabled and turned on; there is
1842 also a small increase in the kernel size if this is enabled.
1843
1844 If unsure, say Y.
1845
Ricardo Neriaa35f892017-11-05 18:27:54 -08001846config X86_INTEL_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001847 def_bool y
Ricardo Neriaa35f892017-11-05 18:27:54 -08001848 depends on CPU_SUP_INTEL
1849 prompt "Intel User Mode Instruction Prevention" if EXPERT
1850 ---help---
1851 The User Mode Instruction Prevention (UMIP) is a security
1852 feature in newer Intel processors. If enabled, a general
Ricardo Neri796ebc82017-11-13 22:29:42 -08001853 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1854 or STR instructions are executed in user mode. These instructions
1855 unnecessarily expose information about the hardware state.
1856
1857 The vast majority of applications do not use these instructions.
1858 For the very few that do, software emulation is provided in
1859 specific cases in protected and virtual-8086 modes. Emulated
1860 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001861
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001862config X86_INTEL_MPX
1863 prompt "Intel MPX (Memory Protection Extensions)"
1864 def_bool n
Rik van Rieldf3735c2017-09-06 16:25:11 -07001865 # Note: only available in 64-bit mode due to VMA flags shortage
1866 depends on CPU_SUP_INTEL && X86_64
1867 select ARCH_USES_HIGH_VMA_FLAGS
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001868 ---help---
1869 MPX provides hardware features that can be used in
1870 conjunction with compiler-instrumented code to check
1871 memory references. It is designed to detect buffer
1872 overflow or underflow bugs.
1873
1874 This option enables running applications which are
1875 instrumented or otherwise use MPX. It does not use MPX
1876 itself inside the kernel or to protect the kernel
1877 against bad memory references.
1878
1879 Enabling this option will make the kernel larger:
1880 ~8k of kernel text and 36 bytes of data on a 64-bit
1881 defconfig. It adds a long to the 'mm_struct' which
1882 will increase the kernel memory overhead of each
1883 process and adds some branches to paths used during
1884 exec() and munmap().
1885
1886 For details, see Documentation/x86/intel_mpx.txt
1887
1888 If unsure, say N.
1889
Dave Hansen35e97792016-02-12 13:02:00 -08001890config X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001891 prompt "Intel Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001892 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001893 # Note: only available in 64-bit mode
Dave Hansen35e97792016-02-12 13:02:00 -08001894 depends on CPU_SUP_INTEL && X86_64
Ingo Molnar52c8e602016-11-15 10:15:03 +01001895 select ARCH_USES_HIGH_VMA_FLAGS
1896 select ARCH_HAS_PKEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001897 ---help---
1898 Memory Protection Keys provides a mechanism for enforcing
1899 page-based protections, but without requiring modification of the
1900 page tables when an application changes protection domains.
1901
1902 For details, see Documentation/x86/protection-keys.txt
1903
1904 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001905
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001906config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001907 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001908 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001909 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001910 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001911 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001912 This enables the kernel to use EFI runtime services that are
1913 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001914
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001915 This option is only useful on systems that have EFI firmware.
1916 In addition, you should use the latest ELILO loader available
1917 at <http://elilo.sourceforge.net> in order to take advantage
1918 of EFI runtime services. However, even with this option, the
1919 resultant kernel should continue to boot on existing non-EFI
1920 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001921
Matt Fleming291f3632011-12-12 21:27:52 +00001922config EFI_STUB
1923 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001924 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001925 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001926 ---help---
1927 This kernel feature allows a bzImage to be loaded directly
1928 by EFI firmware without the use of a bootloader.
1929
Roy Franz4172fe22013-09-22 15:45:25 -07001930 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001931
Matt Fleming7d453ee2014-01-10 18:52:06 +00001932config EFI_MIXED
1933 bool "EFI mixed-mode support"
1934 depends on EFI_STUB && X86_64
1935 ---help---
1936 Enabling this feature allows a 64-bit kernel to be booted
1937 on a 32-bit firmware, provided that your CPU supports 64-bit
1938 mode.
1939
1940 Note that it is not possible to boot a mixed-mode enabled
1941 kernel via the EFI boot stub - a bootloader that supports
1942 the EFI handover protocol must be used.
1943
1944 If unsure, say N.
1945
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001946config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001947 def_bool y
1948 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001949 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001950 This kernel feature is useful for number crunching applications
1951 that may need to compute untrusted bytecode during their
1952 execution. By using pipes or other transports made available to
1953 the process as file descriptors supporting the read/write
1954 syscalls, it's possible to isolate those applications in
1955 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001956 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001957 and the task is only allowed to execute a few safe syscalls
1958 defined by each seccomp mode.
1959
1960 If unsure, say Y. Only embedded should say N here.
1961
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001962source kernel/Kconfig.hz
1963
1964config KEXEC
1965 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001966 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001967 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001968 kexec is a system call that implements the ability to shutdown your
1969 current kernel, and to start another kernel. It is like a reboot
1970 but it is independent of the system firmware. And like a reboot
1971 you can start any kernel with it, not just Linux.
1972
1973 The name comes from the similarity to the exec system call.
1974
1975 It is an ongoing process to be certain the hardware in a machine
1976 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001977 initially work for you. As of this writing the exact hardware
1978 interface is strongly in flux, so no good recommendation can be
1979 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001980
Vivek Goyal74ca3172014-08-29 15:18:46 -07001981config KEXEC_FILE
1982 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07001983 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07001984 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07001985 depends on X86_64
1986 depends on CRYPTO=y
1987 depends on CRYPTO_SHA256=y
1988 ---help---
1989 This is new version of kexec system call. This system call is
1990 file based and takes file descriptors as system call argument
1991 for kernel and initramfs as opposed to list of segments as
1992 accepted by previous system call.
1993
AKASHI Takahirob799a092018-04-13 15:35:45 -07001994config ARCH_HAS_KEXEC_PURGATORY
1995 def_bool KEXEC_FILE
1996
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001997config KEXEC_VERIFY_SIG
1998 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07001999 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002000 ---help---
2001 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002002 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002003
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002004 In addition to that option, you need to enable signature
2005 verification for the corresponding kernel image type being
2006 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002007
2008config KEXEC_BZIMAGE_VERIFY_SIG
2009 bool "Enable bzImage signature verification support"
2010 depends on KEXEC_VERIFY_SIG
2011 depends on SIGNED_PE_FILE_VERIFICATION
2012 select SYSTEM_TRUSTED_KEYRING
2013 ---help---
2014 Enable bzImage signature verification support.
2015
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002016config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002017 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002018 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002019 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002020 Generate crash dump after being started by kexec.
2021 This should be normally only set in special crash dump kernels
2022 which are loaded in the main kernel with kexec-tools into
2023 a specially reserved region and then later executed after
2024 a crash by kdump/kexec. The crash dump kernel must be compiled
2025 to a memory address not used by the main kernel or BIOS using
2026 PHYSICAL_START, or it must be built as a relocatable image
2027 (CONFIG_RELOCATABLE=y).
2028 For more details see Documentation/kdump/kdump.txt
2029
Huang Ying3ab83522008-07-25 19:45:07 -07002030config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002031 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002032 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002033 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07002034 Jump between original kernel and kexeced kernel and invoke
2035 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002036
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002037config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002038 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002039 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002040 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002041 This gives the physical address where the kernel is loaded.
2042
2043 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2044 bzImage will decompress itself to above physical address and
2045 run from there. Otherwise, bzImage will run from the address where
2046 it has been loaded by the boot loader and will ignore above physical
2047 address.
2048
2049 In normal kdump cases one does not have to set/change this option
2050 as now bzImage can be compiled as a completely relocatable image
2051 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2052 address. This option is mainly useful for the folks who don't want
2053 to use a bzImage for capturing the crash dump and want to use a
2054 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2055 to be specifically compiled to run from a specific memory area
2056 (normally a reserved region) and this option comes handy.
2057
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002058 So if you are using bzImage for capturing the crash dump,
2059 leave the value here unchanged to 0x1000000 and set
2060 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2061 for capturing the crash dump change this value to start of
2062 the reserved region. In other words, it can be set based on
2063 the "X" value as specified in the "crashkernel=YM@XM"
2064 command line boot parameter passed to the panic-ed
2065 kernel. Please take a look at Documentation/kdump/kdump.txt
2066 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002067
2068 Usage of bzImage for capturing the crash dump is recommended as
2069 one does not have to build two kernels. Same kernel can be used
2070 as production kernel and capture kernel. Above option should have
2071 gone away after relocatable bzImage support is introduced. But it
2072 is present because there are users out there who continue to use
2073 vmlinux for dump capture. This option should go away down the
2074 line.
2075
2076 Don't change this unless you know what you are doing.
2077
2078config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002079 bool "Build a relocatable kernel"
2080 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002081 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002082 This builds a kernel image that retains relocation information
2083 so it can be loaded someplace besides the default 1MB.
2084 The relocations tend to make the kernel binary about 10% larger,
2085 but are discarded at runtime.
2086
2087 One use is for the kexec on panic case where the recovery kernel
2088 must live at a different physical address than the primary
2089 kernel.
2090
2091 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2092 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002093 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002094
Kees Cook8ab38202013-10-10 17:18:14 -07002095config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002096 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002097 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002098 default y
Kees Cook8ab38202013-10-10 17:18:14 -07002099 ---help---
Baoquan Hee8581e32016-04-20 13:55:43 -07002100 In support of Kernel Address Space Layout Randomization (KASLR),
2101 this randomizes the physical address at which the kernel image
2102 is decompressed and the virtual address where the kernel
2103 image is mapped, as a security feature that deters exploit
2104 attempts relying on knowledge of the location of kernel
2105 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002106
Kees Cooked9f0072016-05-25 15:45:33 -07002107 On 64-bit, the kernel physical and virtual addresses are
2108 randomized separately. The physical address will be anywhere
2109 between 16MB and the top of physical memory (up to 64TB). The
2110 virtual address will be randomized from 16MB up to 1GB (9 bits
2111 of entropy). Note that this also reduces the memory space
2112 available to kernel modules from 1.5GB to 1GB.
2113
2114 On 32-bit, the kernel physical and virtual addresses are
2115 randomized together. They will be randomized from 16MB up to
2116 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002117
Baoquan Hee8581e32016-04-20 13:55:43 -07002118 Entropy is generated using the RDRAND instruction if it is
2119 supported. If RDTSC is supported, its value is mixed into
2120 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002121 supported, then entropy is read from the i8254 timer. The
2122 usable entropy is limited by the kernel being built using
2123 2GB addressing, and that PHYSICAL_ALIGN must be at a
2124 minimum of 2MB. As a result, only 10 bits of entropy are
2125 theoretically possible, but the implementations are further
2126 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002127
Ingo Molnar6807c842017-04-18 11:08:12 +02002128 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002129
2130# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002131config X86_NEED_RELOCS
2132 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002133 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002134
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002135config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002136 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002137 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002138 range 0x2000 0x1000000 if X86_32
2139 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002140 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002141 This value puts the alignment restrictions on physical address
2142 where kernel is loaded and run from. Kernel is compiled for an
2143 address which meets above alignment restriction.
2144
2145 If bootloader loads the kernel at a non-aligned address and
2146 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2147 address aligned to above value and run from there.
2148
2149 If bootloader loads the kernel at a non-aligned address and
2150 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2151 load address and decompress itself to the address it has been
2152 compiled for and run from there. The address for which kernel is
2153 compiled already meets above alignment restrictions. Hence the
2154 end result is that kernel runs from a physical address meeting
2155 above alignment restrictions.
2156
Kees Cooka0215062013-07-08 09:15:17 -07002157 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2158 this value must be a multiple of 0x200000.
2159
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002160 Don't change this unless you know what you are doing.
2161
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002162config DYNAMIC_MEMORY_LAYOUT
2163 bool
2164 ---help---
2165 This option makes base addresses of vmalloc and vmemmap as well as
2166 __PAGE_OFFSET movable during boot.
2167
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002168config RANDOMIZE_MEMORY
2169 bool "Randomize the kernel memory sections"
2170 depends on X86_64
2171 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002172 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002173 default RANDOMIZE_BASE
2174 ---help---
2175 Randomizes the base virtual address of kernel memory sections
2176 (physical memory mapping, vmalloc & vmemmap). This security feature
2177 makes exploits relying on predictable memory locations less reliable.
2178
2179 The order of allocations remains unchanged. Entropy is generated in
2180 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2181 configuration have in average 30,000 different possible virtual
2182 addresses for each memory section.
2183
Ingo Molnar6807c842017-04-18 11:08:12 +02002184 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002185
Thomas Garnier90397a42016-06-21 17:47:06 -07002186config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2187 hex "Physical memory mapping padding" if EXPERT
2188 depends on RANDOMIZE_MEMORY
2189 default "0xa" if MEMORY_HOTPLUG
2190 default "0x0"
2191 range 0x1 0x40 if MEMORY_HOTPLUG
2192 range 0x0 0x40
2193 ---help---
2194 Define the padding in terabytes added to the existing physical
2195 memory size during kernel memory randomization. It is useful
2196 for memory hotplug support but reduces the entropy available for
2197 address randomization.
2198
2199 If unsure, leave at the default value.
2200
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002201config HOTPLUG_CPU
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002202 bool "Support for hot-pluggable CPUs"
Stephen Rothwell40b31362013-05-21 13:49:35 +10002203 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002204 ---help---
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002205 Say Y here to allow turning CPUs off and on. CPUs can be
2206 controlled through /sys/devices/system/cpu.
2207 ( Note: power management support will enable this option
2208 automatically on SMP systems. )
2209 Say N if you want to disable CPU hotplug.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002210
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002211config BOOTPARAM_HOTPLUG_CPU0
2212 bool "Set default setting of cpu0_hotpluggable"
2213 default n
Kees Cook2c922cd2013-01-22 13:01:19 -08002214 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002215 ---help---
2216 Set whether default state of cpu0_hotpluggable is on or off.
2217
2218 Say Y here to enable CPU0 hotplug by default. If this switch
2219 is turned on, there is no need to give cpu0_hotplug kernel
2220 parameter and the CPU0 hotplug feature is enabled by default.
2221
2222 Please note: there are two known CPU0 dependencies if you want
2223 to enable the CPU0 hotplug feature either by this switch or by
2224 cpu0_hotplug kernel parameter.
2225
2226 First, resume from hibernate or suspend always starts from CPU0.
2227 So hibernate and suspend are prevented if CPU0 is offline.
2228
2229 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2230 offline if any interrupt can not migrate out of CPU0. There may
2231 be other CPU0 dependencies.
2232
2233 Please make sure the dependencies are under your control before
2234 you enable this feature.
2235
2236 Say N if you don't want to enable CPU0 hotplug feature by default.
2237 You still can enable the CPU0 hotplug feature at boot by kernel
2238 parameter cpu0_hotplug.
2239
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002240config DEBUG_HOTPLUG_CPU0
2241 def_bool n
2242 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002243 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002244 ---help---
2245 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2246 soon as possible and boots up userspace with CPU0 offlined. User
2247 can online CPU0 back after boot time.
2248
2249 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2250 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2251 compilation or giving cpu0_hotplug kernel parameter at boot.
2252
2253 If unsure, say N.
2254
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002255config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002256 def_bool n
2257 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002258 depends on COMPAT_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002259 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002260 Certain buggy versions of glibc will crash if they are
2261 presented with a 32-bit vDSO that is not mapped at the address
2262 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002263
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002264 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2265 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2266 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2267 the only released version with the bug, but OpenSUSE 9
2268 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002269
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002270 The symptom of the bug is that everything crashes on startup, saying:
2271 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2272
2273 Saying Y here changes the default value of the vdso32 boot
2274 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2275 This works around the glibc bug but hurts performance.
2276
2277 If unsure, say N: if you are compiling your own kernel, you
2278 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002279
Kees Cook3dc33bd2015-08-12 17:55:19 -07002280choice
2281 prompt "vsyscall table for legacy applications"
2282 depends on X86_64
2283 default LEGACY_VSYSCALL_EMULATE
2284 help
2285 Legacy user code that does not know how to find the vDSO expects
2286 to be able to issue three syscalls by calling fixed addresses in
2287 kernel space. Since this location is not randomized with ASLR,
2288 it can be used to assist security vulnerability exploitation.
2289
2290 This setting can be changed at boot time via the kernel command
Andy Lutomirski076ca272018-03-07 11:12:27 -08002291 line parameter vsyscall=[emulate|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002292
2293 On a system with recent enough glibc (2.14 or newer) and no
2294 static binaries, you can say None without a performance penalty
2295 to improve security.
2296
2297 If unsure, select "Emulate".
2298
Kees Cook3dc33bd2015-08-12 17:55:19 -07002299 config LEGACY_VSYSCALL_EMULATE
2300 bool "Emulate"
2301 help
2302 The kernel traps and emulates calls into the fixed
2303 vsyscall address mapping. This makes the mapping
2304 non-executable, but it still contains known contents,
2305 which could be used in certain rare security vulnerability
2306 exploits. This configuration is recommended when userspace
2307 still uses the vsyscall area.
2308
2309 config LEGACY_VSYSCALL_NONE
2310 bool "None"
2311 help
2312 There will be no vsyscall mapping at all. This will
2313 eliminate any risk of ASLR bypass due to the vsyscall
2314 fixed address mapping. Attempts to use the vsyscalls
2315 will be reported to dmesg, so that either old or
2316 malicious userspace programs can be identified.
2317
2318endchoice
2319
Tim Bird516cbf32008-08-12 12:52:36 -07002320config CMDLINE_BOOL
2321 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002322 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002323 Allow for specifying boot arguments to the kernel at
2324 build time. On some systems (e.g. embedded ones), it is
2325 necessary or convenient to provide some or all of the
2326 kernel boot arguments with the kernel itself (that is,
2327 to not rely on the boot loader to provide them.)
2328
2329 To compile command line arguments into the kernel,
2330 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002331 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002332
2333 Systems with fully functional boot loaders (i.e. non-embedded)
2334 should leave this option set to 'N'.
2335
2336config CMDLINE
2337 string "Built-in kernel command string"
2338 depends on CMDLINE_BOOL
2339 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002340 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002341 Enter arguments here that should be compiled into the kernel
2342 image and used at boot time. If the boot loader provides a
2343 command line at boot time, it is appended to this string to
2344 form the full kernel command line, when the system boots.
2345
2346 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2347 change this behavior.
2348
2349 In most cases, the command line (whether built-in or provided
2350 by the boot loader) should specify the device for the root
2351 file system.
2352
2353config CMDLINE_OVERRIDE
2354 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002355 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002356 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002357 Set this option to 'Y' to have the kernel ignore the boot loader
2358 command line, and use ONLY the built-in command line.
2359
2360 This is used to work around broken boot loaders. This should
2361 be set to 'N' under normal conditions.
2362
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002363config MODIFY_LDT_SYSCALL
2364 bool "Enable the LDT (local descriptor table)" if EXPERT
2365 default y
2366 ---help---
2367 Linux can allow user programs to install a per-process x86
2368 Local Descriptor Table (LDT) using the modify_ldt(2) system
2369 call. This is required to run 16-bit or segmented code such as
2370 DOSEMU or some Wine programs. It is also used by some very old
2371 threading libraries.
2372
2373 Enabling this feature adds a small amount of overhead to
2374 context switches and increases the low-level kernel attack
2375 surface. Disabling it removes the modify_ldt(2) system call.
2376
2377 Saying 'N' here may make sense for embedded or server kernels.
2378
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002379source "kernel/livepatch/Kconfig"
2380
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002381endmenu
2382
Michal Hocko3072e412017-09-08 16:11:39 -07002383config ARCH_HAS_ADD_PAGES
2384 def_bool y
2385 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2386
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002387config ARCH_ENABLE_MEMORY_HOTPLUG
2388 def_bool y
2389 depends on X86_64 || (X86_32 && HIGHMEM)
2390
Gary Hade35551052008-10-31 10:52:03 -07002391config ARCH_ENABLE_MEMORY_HOTREMOVE
2392 def_bool y
2393 depends on MEMORY_HOTPLUG
2394
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002395config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002396 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002397 depends on NUMA
2398
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002399config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2400 def_bool y
2401 depends on X86_64 || X86_PAE
2402
Naoya Horiguchic177c812014-06-04 16:05:35 -07002403config ARCH_ENABLE_HUGEPAGE_MIGRATION
2404 def_bool y
2405 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2406
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002407config ARCH_ENABLE_THP_MIGRATION
2408 def_bool y
2409 depends on X86_64 && TRANSPARENT_HUGEPAGE
2410
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002411menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002412
2413config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002414 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002415 depends on X86_64 && HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002416
2417source "kernel/power/Kconfig"
2418
2419source "drivers/acpi/Kconfig"
2420
Feng Tangefafc8b2009-08-14 15:23:29 -04002421source "drivers/sfi/Kconfig"
2422
Andi Kleena6b68072008-01-30 13:32:49 +01002423config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002424 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002425 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002426
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002427menuconfig APM
2428 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002429 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002430 ---help---
2431 APM is a BIOS specification for saving power using several different
2432 techniques. This is mostly useful for battery powered laptops with
2433 APM compliant BIOSes. If you say Y here, the system time will be
2434 reset after a RESUME operation, the /proc/apm device will provide
2435 battery status information, and user-space programs will receive
2436 notification of APM "events" (e.g. battery status change).
2437
2438 If you select "Y" here, you can disable actual use of the APM
2439 BIOS by passing the "apm=off" option to the kernel at boot time.
2440
2441 Note that the APM support is almost completely disabled for
2442 machines with more than one CPU.
2443
2444 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002445 and more information, read <file:Documentation/power/apm-acpi.txt>
2446 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002447 <http://www.tldp.org/docs.html#howto>.
2448
2449 This driver does not spin down disk drives (see the hdparm(8)
2450 manpage ("man 8 hdparm") for that), and it doesn't turn off
2451 VESA-compliant "green" monitors.
2452
2453 This driver does not support the TI 4000M TravelMate and the ACER
2454 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2455 desktop machines also don't have compliant BIOSes, and this driver
2456 may cause those machines to panic during the boot phase.
2457
2458 Generally, if you don't have a battery in your machine, there isn't
2459 much point in using this driver and you should say N. If you get
2460 random kernel OOPSes or reboots that don't seem to be related to
2461 anything, try disabling/enabling this option (or disabling/enabling
2462 APM in your BIOS).
2463
2464 Some other things you should try when experiencing seemingly random,
2465 "weird" problems:
2466
2467 1) make sure that you have enough swap space and that it is
2468 enabled.
2469 2) pass the "no-hlt" option to the kernel
2470 3) switch on floating point emulation in the kernel and pass
2471 the "no387" option to the kernel
2472 4) pass the "floppy=nodma" option to the kernel
2473 5) pass the "mem=4M" option to the kernel (thereby disabling
2474 all but the first 4 MB of RAM)
2475 6) make sure that the CPU is not over clocked.
2476 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2477 8) disable the cache from your BIOS settings
2478 9) install a fan for the video card or exchange video RAM
2479 10) install a better fan for the CPU
2480 11) exchange RAM chips
2481 12) exchange the motherboard.
2482
2483 To compile this driver as a module, choose M here: the
2484 module will be called apm.
2485
2486if APM
2487
2488config APM_IGNORE_USER_SUSPEND
2489 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002490 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002491 This option will ignore USER SUSPEND requests. On machines with a
2492 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2493 series notebooks, it is necessary to say Y because of a BIOS bug.
2494
2495config APM_DO_ENABLE
2496 bool "Enable PM at boot time"
2497 ---help---
2498 Enable APM features at boot time. From page 36 of the APM BIOS
2499 specification: "When disabled, the APM BIOS does not automatically
2500 power manage devices, enter the Standby State, enter the Suspend
2501 State, or take power saving steps in response to CPU Idle calls."
2502 This driver will make CPU Idle calls when Linux is idle (unless this
2503 feature is turned off -- see "Do CPU IDLE calls", below). This
2504 should always save battery power, but more complicated APM features
2505 will be dependent on your BIOS implementation. You may need to turn
2506 this option off if your computer hangs at boot time when using APM
2507 support, or if it beeps continuously instead of suspending. Turn
2508 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2509 T400CDT. This is off by default since most machines do fine without
2510 this feature.
2511
2512config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002513 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002514 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002515 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002516 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2517 On some machines, this can activate improved power savings, such as
2518 a slowed CPU clock rate, when the machine is idle. These idle calls
2519 are made after the idle loop has run for some length of time (e.g.,
2520 333 mS). On some machines, this will cause a hang at boot time or
2521 whenever the CPU becomes idle. (On machines with more than one CPU,
2522 this option does nothing.)
2523
2524config APM_DISPLAY_BLANK
2525 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002526 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002527 Enable console blanking using the APM. Some laptops can use this to
2528 turn off the LCD backlight when the screen blanker of the Linux
2529 virtual console blanks the screen. Note that this is only used by
2530 the virtual console screen blanker, and won't turn off the backlight
2531 when using the X Window system. This also doesn't have anything to
2532 do with your VESA-compliant power-saving monitor. Further, this
2533 option doesn't work for all laptops -- it might not turn off your
2534 backlight at all, or it might print a lot of errors to the console,
2535 especially if you are using gpm.
2536
2537config APM_ALLOW_INTS
2538 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002539 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002540 Normally we disable external interrupts while we are making calls to
2541 the APM BIOS as a measure to lessen the effects of a badly behaving
2542 BIOS implementation. The BIOS should reenable interrupts if it
2543 needs to. Unfortunately, some BIOSes do not -- especially those in
2544 many of the newer IBM Thinkpads. If you experience hangs when you
2545 suspend, try setting this to Y. Otherwise, say N.
2546
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002547endif # APM
2548
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002549source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002550
2551source "drivers/cpuidle/Kconfig"
2552
Andy Henroid27471fd2008-10-09 11:45:22 -07002553source "drivers/idle/Kconfig"
2554
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002555endmenu
2556
2557
2558menu "Bus options (PCI etc.)"
2559
2560config PCI
Ingo Molnar1ac97012008-05-19 14:10:14 +02002561 bool "PCI support"
Adrian Bunk1c858082008-01-30 13:32:32 +01002562 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002563 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002564 Find out whether you have a PCI motherboard. PCI is the name of a
2565 bus system, i.e. the way the CPU talks to the other stuff inside
2566 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2567 VESA. If you have PCI, say Y, otherwise N.
2568
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002569choice
2570 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002571 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002572 default PCI_GOANY
2573 ---help---
2574 On PCI systems, the BIOS can be used to detect the PCI devices and
2575 determine their configuration. However, some old PCI motherboards
2576 have BIOS bugs and may crash if this is done. Also, some embedded
2577 PCI-based systems don't have any BIOS at all. Linux can also try to
2578 detect the PCI hardware directly without using the BIOS.
2579
2580 With this option, you can specify how Linux should detect the
2581 PCI devices. If you choose "BIOS", the BIOS will be used,
2582 if you choose "Direct", the BIOS won't be used, and if you
2583 choose "MMConfig", then PCI Express MMCONFIG will be used.
2584 If you choose "Any", the kernel will try MMCONFIG, then the
2585 direct access method and falls back to the BIOS if that doesn't
2586 work. If unsure, go with the default, which is "Any".
2587
2588config PCI_GOBIOS
2589 bool "BIOS"
2590
2591config PCI_GOMMCONFIG
2592 bool "MMConfig"
2593
2594config PCI_GODIRECT
2595 bool "Direct"
2596
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002597config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002598 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002599 depends on OLPC
2600
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002601config PCI_GOANY
2602 bool "Any"
2603
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002604endchoice
2605
2606config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002607 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002608 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002609
2610# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2611config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002612 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002613 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002614
2615config PCI_MMCONFIG
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002616 bool "Support mmconfig PCI config space access" if X86_64
2617 default y
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002618 depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002619 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002620
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002621config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002622 def_bool y
2623 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002624
Alex Nixonb5401a92010-03-18 16:31:34 -04002625config PCI_XEN
2626 def_bool y
2627 depends on PCI && XEN
2628 select SWIOTLB_XEN
2629
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002630config PCI_DOMAINS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002631 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002632 depends on PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002633
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002634config MMCONF_FAM10H
2635 def_bool y
2636 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002637
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002638config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002639 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002640 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002641 help
2642 Read the PCI windows out of the CNB20LE host bridge. This allows
2643 PCI hotplug to work on systems with the CNB20LE chipset which do
2644 not have ACPI.
2645
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002646 There's no public spec for this chipset, and this functionality
2647 is known to be incomplete.
2648
2649 You should say N unless you know you need this.
2650
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002651source "drivers/pci/Kconfig"
2652
William Breathitt Gray3a495512016-05-27 18:08:27 -04002653config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002654 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002655 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002656 Expose ISA bus device drivers and options available for selection and
2657 configuration. Enable this option if your target machine has an ISA
2658 bus. ISA is an older system, displaced by PCI and newer bus
2659 architectures -- if your target machine is modern, it probably does
2660 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002661
2662 If unsure, say N.
2663
David Rientjes1c00f012011-03-22 16:34:59 -07002664# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002665config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002666 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2667 default y
2668 help
2669 Enables ISA-style DMA support for devices requiring such controllers.
2670 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002671
Linus Torvalds51e68d02016-05-21 10:25:19 -07002672if X86_32
2673
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002674config ISA
2675 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002676 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002677 Find out whether you have ISA slots on your motherboard. ISA is the
2678 name of a bus system, i.e. the way the CPU talks to the other stuff
2679 inside your box. Other bus systems are PCI, EISA, MicroChannel
2680 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2681 newer boards don't support it. If you have ISA, say Y, otherwise N.
2682
2683config EISA
2684 bool "EISA support"
2685 depends on ISA
2686 ---help---
2687 The Extended Industry Standard Architecture (EISA) bus was
2688 developed as an open alternative to the IBM MicroChannel bus.
2689
2690 The EISA bus provided some of the features of the IBM MicroChannel
2691 bus while maintaining backward compatibility with cards made for
2692 the older ISA bus. The EISA bus saw limited use between 1988 and
2693 1995 when it was made obsolete by the PCI bus.
2694
2695 Say Y here if you are building a kernel for an EISA-based machine.
2696
2697 Otherwise, say N.
2698
2699source "drivers/eisa/Kconfig"
2700
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002701config SCx200
2702 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002703 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002704 This provides basic support for National Semiconductor's
2705 (now AMD's) Geode processors. The driver probes for the
2706 PCI-IDs of several on-chip devices, so its a good dependency
2707 for other scx200_* drivers.
2708
2709 If compiled as a module, the driver is named scx200.
2710
2711config SCx200HR_TIMER
2712 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002713 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002714 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002715 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002716 This driver provides a clocksource built upon the on-chip
2717 27MHz high-resolution timer. Its also a workaround for
2718 NSC Geode SC-1100's buggy TSC, which loses time when the
2719 processor goes idle (as is done by the scheduler). The
2720 other workaround is idle=poll boot option.
2721
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002722config OLPC
2723 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002724 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002725 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002726 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002727 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002728 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002729 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002730 Add support for detecting the unique features of the OLPC
2731 XO hardware.
2732
Daniel Drakea3128582011-06-25 17:34:10 +01002733config OLPC_XO1_PM
2734 bool "OLPC XO-1 Power Management"
Daniel Drake97c4cb72011-06-25 17:34:11 +01002735 depends on OLPC && MFD_CS5535 && PM_SLEEP
Daniel Drakea3128582011-06-25 17:34:10 +01002736 select MFD_CORE
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002737 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002738 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002739
Daniel Drakecfee9592011-06-25 17:34:17 +01002740config OLPC_XO1_RTC
2741 bool "OLPC XO-1 Real Time Clock"
2742 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2743 ---help---
2744 Add support for the XO-1 real time clock, which can be used as a
2745 programmable wakeup source.
2746
Daniel Drake7feda8e2011-06-25 17:34:12 +01002747config OLPC_XO1_SCI
2748 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002749 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002750 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002751 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002752 ---help---
2753 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002754 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002755 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002756 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002757 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002758 - AC adapter status updates
2759 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002760
Daniel Drakea0f30f52011-06-25 17:34:18 +01002761config OLPC_XO15_SCI
2762 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002763 depends on OLPC && ACPI
2764 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002765 ---help---
2766 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2767 - EC-driven system wakeups
2768 - AC adapter status updates
2769 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002770
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002771config ALIX
2772 bool "PCEngines ALIX System Support (LED setup)"
2773 select GPIOLIB
2774 ---help---
2775 This option enables system support for the PCEngines ALIX.
2776 At present this just sets up LEDs for GPIO control on
2777 ALIX2/3/6 boards. However, other system specific setup should
2778 get added here.
2779
2780 Note: You must still enable the drivers for GPIO and LED support
2781 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2782
2783 Note: You have to set alix.force=1 for boards with Award BIOS.
2784
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002785config NET5501
2786 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2787 select GPIOLIB
2788 ---help---
2789 This option enables system support for the Soekris Engineering net5501.
2790
Philip A. Prindeville31970592012-01-14 01:45:39 -07002791config GEOS
2792 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2793 select GPIOLIB
2794 depends on DMI
2795 ---help---
2796 This option enables system support for the Traverse Technologies GEOS.
2797
Vivien Didelot7d029122013-01-04 16:18:14 -05002798config TS5500
2799 bool "Technologic Systems TS-5500 platform support"
2800 depends on MELAN
2801 select CHECK_SIGNATURE
2802 select NEW_LEDS
2803 select LEDS_CLASS
2804 ---help---
2805 This option enables system support for the Technologic Systems TS-5500.
2806
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002807endif # X86_32
2808
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002809config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002810 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002811 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002812
2813source "drivers/pcmcia/Kconfig"
2814
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002815config RAPIDIO
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002816 tristate "RapidIO support"
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002817 depends on PCI
2818 default n
2819 help
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002820 If enabled this option will include drivers and the core
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002821 infrastructure code to support RapidIO interconnect devices.
2822
2823source "drivers/rapidio/Kconfig"
2824
David Herrmanne3263ab2013-08-02 14:05:22 +02002825config X86_SYSFB
2826 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2827 help
2828 Firmwares often provide initial graphics framebuffers so the BIOS,
2829 bootloader or kernel can show basic video-output during boot for
2830 user-guidance and debugging. Historically, x86 used the VESA BIOS
2831 Extensions and EFI-framebuffers for this, which are mostly limited
2832 to x86.
2833 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2834 framebuffers so the new generic system-framebuffer drivers can be
2835 used on x86. If the framebuffer is not compatible with the generic
2836 modes, it is adverticed as fallback platform framebuffer so legacy
2837 drivers like efifb, vesafb and uvesafb can pick it up.
2838 If this option is not selected, all system framebuffers are always
2839 marked as fallback platform framebuffers as usual.
2840
2841 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2842 not be able to pick up generic system framebuffers if this option
2843 is selected. You are highly encouraged to enable simplefb as
2844 replacement if you select this option. simplefb can correctly deal
2845 with generic system framebuffers. But you should still keep vesafb
2846 and others enabled as fallback if a system framebuffer is
2847 incompatible with simplefb.
2848
2849 If unsure, say Y.
2850
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002851endmenu
2852
2853
2854menu "Executable file formats / Emulations"
2855
2856source "fs/Kconfig.binfmt"
2857
2858config IA32_EMULATION
2859 bool "IA32 Emulation"
2860 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002861 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002862 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002863 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002864 select COMPAT_OLD_SIGACTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002865 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002866 Include code to run legacy 32-bit programs under a
2867 64-bit kernel. You should likely turn this on, unless you're
2868 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002869
2870config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002871 tristate "IA32 a.out support"
2872 depends on IA32_EMULATION
2873 ---help---
2874 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002875
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002876config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002877 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002878 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002879 ---help---
2880 Include code to run binaries for the x32 native 32-bit ABI
2881 for 64-bit processors. An x32 process gets access to the
2882 full 64-bit register file and wide data path while leaving
2883 pointers at 32 bits for smaller memory footprint.
2884
2885 You will need a recent binutils (2.22 or later) with
2886 elf32_x86_64 support enabled to compile a kernel with this
2887 option set.
2888
Ingo Molnar953fee12016-11-15 10:22:52 +01002889config COMPAT_32
2890 def_bool y
2891 depends on IA32_EMULATION || X86_32
2892 select HAVE_UID16
2893 select OLD_SIGSUSPEND3
2894
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002895config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002896 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002897 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002898
Jan Beulich3120e252012-09-10 12:41:45 +01002899if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002900config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002901 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002902
2903config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002904 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002905 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002906endif
David Howellsee009e4a02011-03-07 15:06:20 +00002907
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002908endmenu
2909
2910
Keith Packarde5beae12008-11-03 18:21:45 +01002911config HAVE_ATOMIC_IOMAP
2912 def_bool y
2913 depends on X86_32
2914
Alessandro Rubini4692d772012-04-04 19:39:58 +02002915config X86_DEV_DMA_OPS
2916 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002917 depends on X86_64 || STA2X11
Alessandro Rubini4692d772012-04-04 19:39:58 +02002918
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002919config X86_DMA_REMAP
2920 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002921 depends on STA2X11
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002922
Kirill A. Shutemove5855132017-06-06 14:31:20 +03002923config HAVE_GENERIC_GUP
2924 def_bool y
2925
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002926source "net/Kconfig"
2927
2928source "drivers/Kconfig"
2929
2930source "drivers/firmware/Kconfig"
2931
2932source "fs/Kconfig"
2933
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002934source "arch/x86/Kconfig.debug"
2935
2936source "security/Kconfig"
2937
2938source "crypto/Kconfig"
2939
Avi Kivityedf88412007-12-16 11:02:48 +02002940source "arch/x86/kvm/Kconfig"
2941
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002942source "lib/Kconfig"