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Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01001# Select 32 or 64 bit
2config 64BIT
Sam Ravnborg68409992007-11-17 15:37:31 +01003 bool "64-bit kernel" if ARCH = "x86"
David Woodhouseffee0de2012-12-20 21:51:55 +00004 default ARCH != "i386"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01005 ---help---
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01006 Say yes to build a 64-bit kernel - formerly known as x86_64
7 Say no to build a 32-bit kernel - formerly known as i386
8
9config X86_32
Jan Beulich3120e252012-09-10 12:41:45 +010010 def_bool y
11 depends on !64BIT
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +010012
13config X86_64
Jan Beulich3120e252012-09-10 12:41:45 +010014 def_bool y
15 depends on 64BIT
Sam Ravnborg1032c0b2007-11-06 21:35:08 +010016
17### Arch settings
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +010018config X86
Harvey Harrison3c2362e2008-01-30 13:31:03 +010019 def_bool y
Ingo Molnar6471b822015-06-03 10:00:13 +020020 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
21 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
Ingo Molnar6471b822015-06-03 10:00:13 +020022 select ARCH_CLOCKSOURCE_DATA
23 select ARCH_DISCARD_MEMBLOCK
Aleksey Makarov91dda512016-06-20 13:56:12 +030024 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
Dan Williams21266be2015-11-19 18:19:29 -080025 select ARCH_HAS_DEVMEM_IS_ALLOWED
Ingo Molnar6471b822015-06-03 10:00:13 +020026 select ARCH_HAS_ELF_RANDOMIZE
Linus Torvalds72d93102014-09-13 11:14:53 -070027 select ARCH_HAS_FAST_MULTIPLIER
Riku Voipio957e3fa2014-12-12 16:57:44 -080028 select ARCH_HAS_GCOV_PROFILE_ALL
Yisheng Xie461a7182016-10-07 17:01:46 -070029 select ARCH_HAS_GIGANTIC_PAGE if X86_64
Dmitry Vyukov5c9a8752016-03-22 14:27:30 -070030 select ARCH_HAS_KCOV if X86_64
Dan Williams96601ad2015-08-24 18:29:38 -040031 select ARCH_HAS_PMEM_API if X86_64
Ross Zwisler67a3e8f2015-08-27 13:14:20 -060032 select ARCH_HAS_MMIO_FLUSH
Ingo Molnar6471b822015-06-03 10:00:13 +020033 select ARCH_HAS_SG_CHAIN
Andrey Ryabininc6d30852016-01-20 15:00:55 -080034 select ARCH_HAS_UBSAN_SANITIZE_ALL
Ingo Molnar6471b822015-06-03 10:00:13 +020035 select ARCH_HAVE_NMI_SAFE_CMPXCHG
36 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040037 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080038 select ARCH_MIGHT_HAVE_PC_SERIO
Ingo Molnar6471b822015-06-03 10:00:13 +020039 select ARCH_SUPPORTS_ATOMIC_RMW
Mel Gorman3b242c62015-06-30 14:57:13 -070040 select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
Ingo Molnar6471b822015-06-03 10:00:13 +020041 select ARCH_SUPPORTS_INT128 if X86_64
42 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
43 select ARCH_USE_BUILTIN_BSWAP
44 select ARCH_USE_CMPXCHG_LOCKREF if X86_64
45 select ARCH_USE_QUEUED_RWLOCKS
46 select ARCH_USE_QUEUED_SPINLOCKS
Andy Lutomirski3e5daac2017-05-28 10:00:14 -070047 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Ingo Molnar5aaeb5c2015-07-17 12:28:12 +020048 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Ingo Molnarda4276b2009-01-07 11:05:10 +010049 select ARCH_WANT_FRAME_POINTERS
Ingo Molnar6471b822015-06-03 10:00:13 +020050 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
Ingo Molnar6471b822015-06-03 10:00:13 +020051 select BUILDTIME_EXTABLE_SORT
52 select CLKEVT_I8253
53 select CLKSRC_I8253 if X86_32
54 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
55 select CLOCKSOURCE_WATCHDOG
56 select CLONE_BACKWARDS if X86_32
57 select COMPAT_OLD_SIGACTION if IA32_EMULATION
58 select DCACHE_WORD_ACCESS
Linus Torvalds45471cd2015-06-24 19:52:06 -070059 select EDAC_ATOMIC_SCRUB
60 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +020061 select GENERIC_CLOCKEVENTS
62 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
63 select GENERIC_CLOCKEVENTS_MIN_ADJUST
64 select GENERIC_CMOS_UPDATE
65 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner45a98822018-01-07 22:48:01 +010066 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +020067 select GENERIC_EARLY_IOREMAP
68 select GENERIC_FIND_FIRST_BIT
69 select GENERIC_IOMAP
70 select GENERIC_IRQ_PROBE
71 select GENERIC_IRQ_SHOW
72 select GENERIC_PENDING_IRQ if SMP
73 select GENERIC_SMP_IDLE_THREAD
74 select GENERIC_STRNCPY_FROM_USER
75 select GENERIC_STRNLEN_USER
76 select GENERIC_TIME_VSYSCALL
77 select HAVE_ACPI_APEI if ACPI
78 select HAVE_ACPI_APEI_NMI if ACPI
79 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
80 select HAVE_AOUT if X86_32
81 select HAVE_ARCH_AUDITSYSCALL
Kees Cook5b710f32016-06-23 15:04:01 -070082 select HAVE_ARCH_HARDENED_USERCOPY
Ingo Molnar6471b822015-06-03 10:00:13 +020083 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
84 select HAVE_ARCH_JUMP_LABEL
85 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
86 select HAVE_ARCH_KGDB
87 select HAVE_ARCH_KMEMCHECK
Daniel Cashman9e08f572016-01-14 15:20:06 -080088 select HAVE_ARCH_MMAP_RND_BITS if MMU
89 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Ingo Molnar6471b822015-06-03 10:00:13 +020090 select HAVE_ARCH_SECCOMP_FILTER
91 select HAVE_ARCH_SOFT_DIRTY if X86_64
92 select HAVE_ARCH_TRACEHOOK
93 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Kees Cook0f60a8e2016-07-12 16:19:48 -070094 select HAVE_ARCH_WITHIN_STACK_FRAMES
Daniel Borkmann60777762016-05-13 19:08:28 +020095 select HAVE_EBPF_JIT if X86_64
Andy Lutomirskie37e43a2016-08-11 02:35:23 -070096 select HAVE_ARCH_VMAP_STACK if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020097 select HAVE_CC_STACKPROTECTOR
98 select HAVE_CMPXCHG_DOUBLE
99 select HAVE_CMPXCHG_LOCAL
100 select HAVE_CONTEXT_TRACKING if X86_64
Josh Triplettc1bd55f2015-06-30 15:00:00 -0700101 select HAVE_COPY_THREAD_TLS
Ingo Molnar6471b822015-06-03 10:00:13 +0200102 select HAVE_C_RECORDMCOUNT
103 select HAVE_DEBUG_KMEMLEAK
104 select HAVE_DEBUG_STACKOVERFLOW
105 select HAVE_DMA_API_DEBUG
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700106 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400107 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900108 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Johannes Berg58340a02008-07-25 01:45:33 -0700109 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Jiri Slaby5f56a5d2016-05-20 17:00:16 -0700110 select HAVE_EXIT_THREAD
Ingo Molnar6471b822015-06-03 10:00:13 +0200111 select HAVE_FENTRY if X86_64
112 select HAVE_FTRACE_MCOUNT_RECORD
Ingo Molnar6471b822015-06-03 10:00:13 +0200113 select HAVE_FUNCTION_GRAPH_TRACER
114 select HAVE_FUNCTION_TRACER
Emese Revfy6b90bd42016-05-24 00:09:38 +0200115 select HAVE_GCC_PLUGINS
Ingo Molnar6471b822015-06-03 10:00:13 +0200116 select HAVE_GENERIC_DMA_COHERENT if X86_32
K.Prasad0067f122009-06-01 23:43:57 +0530117 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200118 select HAVE_IDE
119 select HAVE_IOREMAP_PROT
120 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
121 select HAVE_IRQ_TIME_ACCOUNTING
122 select HAVE_KERNEL_BZIP2
123 select HAVE_KERNEL_GZIP
124 select HAVE_KERNEL_LZ4
125 select HAVE_KERNEL_LZMA
126 select HAVE_KERNEL_LZO
127 select HAVE_KERNEL_XZ
128 select HAVE_KPROBES
129 select HAVE_KPROBES_ON_FTRACE
130 select HAVE_KRETPROBES
131 select HAVE_KVM
132 select HAVE_LIVEPATCH if X86_64
133 select HAVE_MEMBLOCK
134 select HAVE_MEMBLOCK_NODE_MAP
Frederic Weisbecker01027522010-04-11 18:55:56 +0200135 select HAVE_MIXED_BREAKPOINTS_REGS
Petr Mladek42a0bb32016-05-20 17:00:33 -0700136 select HAVE_NMI
Ingo Molnar6471b822015-06-03 10:00:13 +0200137 select HAVE_OPROFILE
138 select HAVE_OPTPROBES
139 select HAVE_PCSPKR_PLATFORM
140 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200141 select HAVE_PERF_EVENTS_NMI
Jiri Olsac5e63192012-08-07 15:20:36 +0200142 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200143 select HAVE_PERF_USER_STACK_DUMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200144 select HAVE_REGS_AND_STACK_ACCESS_API
145 select HAVE_SYSCALL_TRACEPOINTS
Brian Gerst0c3619e2015-06-22 07:55:20 -0400146 select HAVE_UID16 if X86_32 || IA32_EMULATION
Ingo Molnar6471b822015-06-03 10:00:13 +0200147 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300148 select HAVE_USER_RETURN_NOTIFIER
Thomas Gleixnerf37486c2018-05-29 17:48:27 +0200149 select HOTPLUG_SMT if SMP
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100150 select IRQ_FORCED_THREADING
Ingo Molnar6471b822015-06-03 10:00:13 +0200151 select MODULES_USE_ELF_RELA if X86_64
152 select MODULES_USE_ELF_REL if X86_32
153 select OLD_SIGACTION if X86_32
154 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
155 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500156 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200157 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200158 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500159 select SRCU
Ingo Molnar6471b822015-06-03 10:00:13 +0200160 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700161 select THREAD_INFO_IN_TASK
Ingo Molnar6471b822015-06-03 10:00:13 +0200162 select USER_STACKTRACE_SUPPORT
163 select VIRT_TO_BUS
164 select X86_DEV_DMA_OPS if X86_64
165 select X86_FEATURE_NAMES if PROC_FS
Josh Poimboeufd4883d52016-02-28 22:22:43 -0600166 select HAVE_STACK_VALIDATION if X86_64
Dave Hansen63c17fb2016-02-12 13:02:08 -0800167 select ARCH_USES_HIGH_VMA_FLAGS if X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen66d37572016-02-12 13:02:32 -0800168 select ARCH_HAS_PKEYS if X86_INTEL_MEMORY_PROTECTION_KEYS
Balbir Singh7d8330a2008-02-10 12:46:28 +0530169
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200170config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100171 def_bool y
172 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200173
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700174config OUTPUT_FORMAT
175 string
176 default "elf32-i386" if X86_32
177 default "elf64-x86-64" if X86_64
178
Sam Ravnborg73531902008-05-25 23:03:18 +0200179config ARCH_DEFCONFIG
Sam Ravnborgb9b39bf2008-04-29 12:48:15 +0200180 string
Sam Ravnborg73531902008-05-25 23:03:18 +0200181 default "arch/x86/configs/i386_defconfig" if X86_32
182 default "arch/x86/configs/x86_64_defconfig" if X86_64
Sam Ravnborgb9b39bf2008-04-29 12:48:15 +0200183
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100184config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100185 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100186
187config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100188 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100189
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100190config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100191 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100192
Daniel Cashman9e08f572016-01-14 15:20:06 -0800193config ARCH_MMAP_RND_BITS_MIN
194 default 28 if 64BIT
195 default 8
196
197config ARCH_MMAP_RND_BITS_MAX
198 default 32 if 64BIT
199 default 16
200
201config ARCH_MMAP_RND_COMPAT_BITS_MIN
202 default 8
203
204config ARCH_MMAP_RND_COMPAT_BITS_MAX
205 default 16
206
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100207config SBUS
208 bool
209
FUJITA Tomonori3bc4e452010-03-10 15:23:22 -0800210config NEED_DMA_MAP_STATE
Jan Beulich3120e252012-09-10 12:41:45 +0100211 def_bool y
Konrad Rzeszutek Wilka6dfa122015-04-17 15:04:48 -0400212 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
FUJITA Tomonori3bc4e452010-03-10 15:23:22 -0800213
FUJITA Tomonori18e98302010-05-26 14:44:32 -0700214config NEED_SG_DMA_LENGTH
Andrew Morton4a14d842010-05-26 14:44:33 -0700215 def_bool y
FUJITA Tomonori18e98302010-05-26 14:44:32 -0700216
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100217config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100218 def_bool y
219 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100220
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100221config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100222 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100223 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000224 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
225
226config GENERIC_BUG_RELATIVE_POINTERS
227 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100228
229config GENERIC_HWEIGHT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100230 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100231
232config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100233 def_bool y
234 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100235
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100236config RWSEM_XCHGADD_ALGORITHM
Jan Beulich3120e252012-09-10 12:41:45 +0100237 def_bool y
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100238
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100239config GENERIC_CALIBRATE_DELAY
240 def_bool y
241
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800242config ARCH_HAS_CPU_RELAX
243 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100244
Pekka Enberg1b27d052008-04-28 02:12:22 -0700245config ARCH_HAS_CACHE_LINE_SIZE
246 def_bool y
247
Mike Travisdd5af902008-01-30 13:33:32 +0100248config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900249 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100250
Tejun Heo08fc4582009-08-14 15:00:49 +0900251config NEED_PER_CPU_EMBED_FIRST_CHUNK
252 def_bool y
253
254config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900255 def_bool y
256
Johannes Berg801e4062007-12-08 02:12:39 +0100257config ARCH_HIBERNATION_POSSIBLE
258 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100259
Johannes Bergf4cb5702007-12-08 02:14:00 +0100260config ARCH_SUSPEND_POSSIBLE
261 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100262
Steve Cappercfe28c52013-04-29 14:29:48 +0100263config ARCH_WANT_HUGE_PMD_SHARE
264 def_bool y
265
Steve Capper53313b22013-04-30 08:03:42 +0100266config ARCH_WANT_GENERAL_HUGETLB
267 def_bool y
268
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100269config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000270 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100271
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100272config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000273 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100274
Ingo Molnar765c68b2008-04-09 11:03:37 +0200275config ARCH_SUPPORTS_OPTIMIZED_INLINING
276 def_bool y
277
Akinobu Mita6a11f752009-03-31 15:23:17 -0700278config ARCH_SUPPORTS_DEBUG_PAGEALLOC
279 def_bool y
280
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300281config KASAN_SHADOW_OFFSET
282 hex
283 depends on KASAN
284 default 0xdffffc0000000000
285
Shane Wang69575d32009-09-01 18:25:07 -0700286config HAVE_INTEL_TXT
287 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700288 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700289
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100290config X86_32_SMP
291 def_bool y
292 depends on X86_32 && SMP
293
294config X86_64_SMP
295 def_bool y
296 depends on X86_64 && SMP
297
Tejun Heoccbeed32009-02-09 22:17:40 +0900298config X86_32_LAZY_GS
299 def_bool y
Tejun Heo60a53172009-02-09 22:17:40 +0900300 depends on X86_32 && !CC_STACKPROTECTOR
Tejun Heoccbeed32009-02-09 22:17:40 +0900301
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530302config ARCH_SUPPORTS_UPROBES
303 def_bool y
304
Rob Herringd20642f2014-04-18 17:19:54 -0500305config FIX_EARLYCON_MEM
306 def_bool y
307
Kees Cook9ccaf772016-02-17 14:41:14 -0800308config DEBUG_RODATA
309 def_bool y
310
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700311config PGTABLE_LEVELS
312 int
313 default 4 if X86_64
314 default 3 if X86_PAE
315 default 2
316
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100317source "init/Kconfig"
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700318source "kernel/Kconfig.freezer"
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100319
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100320menu "Processor type and features"
321
Randy Dunlap5ee71532012-01-16 11:57:18 -0800322config ZONE_DMA
323 bool "DMA memory allocation support" if EXPERT
324 default y
325 help
326 DMA memory allocation support allows devices with less than 32-bit
327 addressing to allocate within the first 16MB of address space.
328 Disable if no such devices will be used.
329
330 If unsure, say Y.
331
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100332config SMP
333 bool "Symmetric multi-processing support"
334 ---help---
335 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800336 a system with only one CPU, say N. If you have a system with more
337 than one CPU, say Y.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100338
Robert Graffham4a474152014-01-23 15:55:29 -0800339 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100340 machines, but will use only one CPU of a multiprocessor machine. If
341 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800342 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100343 will run faster if you say N here.
344
345 Note that if you say Y here and choose architecture "586" or
346 "Pentium" under "Processor family", the kernel will not work on 486
347 architectures. Similarly, multiprocessor kernels for the "PPro"
348 architecture may not work on all Pentium based boards.
349
350 People using multiprocessor machines who say Y here should also say
351 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
352 Management" code will be disabled if you say Y here.
353
Paul Bolle395cf962011-08-15 02:02:26 +0200354 See also <file:Documentation/x86/i386/IO-APIC.txt>,
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100355 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
356 <http://www.tldp.org/docs.html#howto>.
357
358 If you don't know what to do here, say N.
359
Josh Triplett9def39be2013-10-30 08:09:45 -0700360config X86_FEATURE_NAMES
361 bool "Processor feature human-readable names" if EMBEDDED
362 default y
363 ---help---
364 This option compiles in a table of x86 feature bits and corresponding
365 names. This is required to support /proc/cpuinfo and a few kernel
366 messages. You can disable this to save space, at the expense of
367 making those few kernel messages show numeric feature bits instead.
368
369 If in doubt, say Y.
370
Borislav Petkov6e1315f2015-12-07 10:39:42 +0100371config X86_FAST_FEATURE_TESTS
372 bool "Fast CPU feature tests" if EMBEDDED
373 default y
374 ---help---
375 Some fast-paths in the kernel depend on the capabilities of the CPU.
376 Say Y here for the kernel to patch in the appropriate code at runtime
377 based on the capabilities of the CPU. The infrastructure for patching
378 code at runtime takes up some additional space; space-constrained
379 embedded systems may wish to say N here to produce smaller, slightly
380 slower code.
381
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800382config X86_X2APIC
383 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200384 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800385 ---help---
386 This enables x2apic support on CPUs that have this feature.
387
388 This allows 32-bit apic IDs (so it can support very large systems),
389 and accesses the local apic via MSRs not via mmio.
390
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800391 If you don't know what to do here, say N.
392
Yinghai Lu6695c852008-06-19 12:13:09 -0700393config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700394 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000395 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200396 depends on X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100397 ---help---
Yinghai Lu6695c852008-06-19 12:13:09 -0700398 For old smp systems that do not have proper acpi support. Newer systems
399 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700400
Yinghai Lu26f7ef12009-01-29 14:19:22 -0800401config X86_BIGSMP
402 bool "Support for big SMP systems with more than 8 CPUs"
403 depends on X86_32 && SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100404 ---help---
Yinghai Lu26f7ef12009-01-29 14:19:22 -0800405 This option is needed for the systems that have more than 8 CPUs
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100406
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000407config GOLDFISH
408 def_bool y
409 depends on X86_GOLDFISH
410
David Woodhouse2bb5de42018-01-11 21:46:25 +0000411config RETPOLINE
412 bool "Avoid speculative indirect branches in kernel"
413 default y
414 ---help---
415 Compile kernel with the retpoline compiler options to guard against
416 kernel-to-user data leaks by avoiding speculative indirect
417 branches. Requires a compiler with -mindirect-branch=thunk-extern
418 support for full protection. The kernel may run slower.
419
420 Without compiler support, at least indirect branches in assembler
421 code are eliminated. Since this includes the syscall entry path,
422 it is not entirely pointless.
423
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800424if X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800425config X86_EXTENDED_PLATFORM
426 bool "Support for extended (non-PC) x86 platforms"
427 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100428 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100429 If you disable this option then the kernel will only support
430 standard PC platforms. (which covers the vast majority of
431 systems out there.)
432
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800433 If you enable this option then you'll be able to select support
434 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100435 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800436 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800437 RDC R-321x SoC
438 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200439 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200440 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100441
442 If you have one of these systems, or if you want to build a
443 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800444endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100445
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800446if X86_64
447config X86_EXTENDED_PLATFORM
448 bool "Support for extended (non-PC) x86 platforms"
449 default y
450 ---help---
451 If you disable this option then the kernel will only support
452 standard PC platforms. (which covers the vast majority of
453 systems out there.)
454
455 If you enable this option then you'll be able to select support
456 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b2011-12-06 00:07:26 +0800457 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800458 ScaleMP vSMP
459 SGI Ultraviolet
460
461 If you have one of these systems, or if you want to build a
462 generic distribution kernel, say Y here - otherwise say N.
463endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800464# This is an alphabetically sorted list of 64 bit extended platforms
465# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b2011-12-06 00:07:26 +0800466config X86_NUMACHIP
467 bool "Numascale NumaChip"
468 depends on X86_64
469 depends on X86_EXTENDED_PLATFORM
470 depends on NUMA
471 depends on SMP
472 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700473 depends on PCI_MMCONFIG
Steffen Persvold44b111b2011-12-06 00:07:26 +0800474 ---help---
475 Adds support for Numascale NumaChip large-SMP systems. Needed to
476 enable more than ~168 cores.
477 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100478
Ingo Molnar6a485652009-01-27 18:29:13 +0100479config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800480 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100481 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100482 select PARAVIRT
483 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800484 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300485 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100486 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100487 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
488 supposed to run on these EM64T-based machines. Only choose this option
489 if you have one of these machines.
490
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800491config X86_UV
492 bool "SGI Ultraviolet"
493 depends on X86_64
494 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500495 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800496 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700497 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200498 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800499 ---help---
500 This option is needed in order to support SGI Ultraviolet systems.
501 If you don't have one of these, you should say N here.
502
503# Following is an alphabetically sorted list of 32 bit extended platforms
504# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100505
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000506config X86_GOLDFISH
507 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100508 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000509 ---help---
510 Enable support for the Goldfish virtual platform used primarily
511 for Android development. Unless you are building for the Android
512 Goldfish emulator say N here.
513
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800514config X86_INTEL_CE
515 bool "CE4100 TV platform"
516 depends on PCI
517 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800518 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800519 depends on X86_32
520 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800521 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100522 select OF
523 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800524 ---help---
525 Select for the Intel CE media processor (CE4100) SOC.
526 This option compiles in support for the CE4100 SOC for settop
527 boxes and media devices.
528
David Cohen4cb9b002013-12-16 17:37:26 -0800529config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100530 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100531 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800532 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000533 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200534 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000535 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000536 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800537 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000538 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000539 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000540 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000541 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000542 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800543 Select to build a kernel capable of supporting Intel MID (Mobile
544 Internet Device) platform systems which do not have the PCI legacy
545 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000546
David Cohen4cb9b002013-12-16 17:37:26 -0800547 Intel MID platforms are based on an Intel processor and chipset which
548 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100549
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000550config X86_INTEL_QUARK
551 bool "Intel Quark platform support"
552 depends on X86_32
553 depends on X86_EXTENDED_PLATFORM
554 depends on X86_PLATFORM_DEVICES
555 depends on X86_TSC
556 depends on PCI
557 depends on PCI_GOANY
558 depends on X86_IO_APIC
559 select IOSF_MBI
560 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200561 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000562 ---help---
563 Select to include support for Quark X1000 SoC.
564 Say Y here if you have a Quark based system such as the Arduino
565 compatible Intel Galileo.
566
Vadim Pasternak58cbbee2016-09-22 21:13:42 +0000567config MLX_PLATFORM
568 tristate "Mellanox Technologies platform support"
569 depends on X86_64
570 depends on X86_EXTENDED_PLATFORM
571 ---help---
572 This option enables system support for the Mellanox Technologies
573 platform.
574
575 Say Y here if you are building a kernel for Mellanox system.
576
577 Otherwise, say N.
578
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000579config X86_INTEL_LPSS
580 bool "Intel Low Power Subsystem Support"
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100581 depends on X86 && ACPI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000582 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300583 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100584 select IOSF_MBI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000585 ---help---
586 Select to build support for Intel Low Power Subsystem such as
587 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300588 things like clock tree (common clock framework) and pincontrol
589 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000590
Ken Xue92082a82015-02-06 08:27:51 +0800591config X86_AMD_PLATFORM_DEVICE
592 bool "AMD ACPI2Platform devices support"
593 depends on ACPI
594 select COMMON_CLK
595 select PINCTRL
596 ---help---
597 Select to interpret AMD specific ACPI device to platform device
598 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
599 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
600 implemented under PINCTRL subsystem.
601
David E. Boxced3ce72014-09-17 22:13:50 -0700602config IOSF_MBI
603 tristate "Intel SoC IOSF Sideband support for SoC platforms"
604 depends on PCI
605 ---help---
606 This option enables sideband register access support for Intel SoC
607 platforms. On these platforms the IOSF sideband is used in lieu of
608 MSR's for some register accesses, mostly but not limited to thermal
609 and power. Drivers may query the availability of this device to
610 determine if they need the sideband in order to work on these
611 platforms. The sideband is available on the following SoC products.
612 This list is not meant to be exclusive.
613 - BayTrail
614 - Braswell
615 - Quark
616
617 You should say Y if you are running a kernel on one of these SoC's.
618
David E. Boxed2226b2014-09-17 22:13:51 -0700619config IOSF_MBI_DEBUG
620 bool "Enable IOSF sideband access through debugfs"
621 depends on IOSF_MBI && DEBUG_FS
622 ---help---
623 Select this option to expose the IOSF sideband access registers (MCR,
624 MDR, MCRX) through debugfs to write and read register information from
625 different units on the SoC. This is most useful for obtaining device
626 state information for debug and analysis. As this is a general access
627 mechanism, users of this option would have specific knowledge of the
628 device they want to access.
629
630 If you don't require the option or are in doubt, say N.
631
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800632config X86_RDC321X
633 bool "RDC R-321x SoC"
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100634 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800635 depends on X86_EXTENDED_PLATFORM
636 select M486
637 select X86_REBOOTFIXUPS
638 ---help---
639 This option is needed for RDC R-321x system-on-chip, also known
640 as R-8610-(G).
641 If you don't have one of these chips, you should say N here.
642
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100643config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100644 bool "Support non-standard 32-bit SMP architectures"
645 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800646 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100647 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800648 This option compiles in the bigsmp and STA2X11 default
649 subarchitectures. It is intended for a generic binary
650 kernel. If you select them all, kernel will probe it one by
651 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700652
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800653# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700654
Linus Torvaldsd949f362009-09-26 09:35:07 -0700655config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100656 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700657 # MCE code calls memory_failure():
658 depends on X86_MCE
659 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700660 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
661 depends on X86_64 || !SPARSEMEM
662 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700663
Alessandro Rubini83125a32012-04-04 19:40:21 +0200664config STA2X11
665 bool "STA2X11 Companion Chip Support"
666 depends on X86_32_NON_STANDARD && PCI
667 select X86_DEV_DMA_OPS
668 select X86_DMA_REMAP
669 select SWIOTLB
670 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200671 select GPIOLIB
Alessandro Rubini83125a32012-04-04 19:40:21 +0200672 default n
673 ---help---
674 This adds support for boards based on the STA2X11 IO-Hub,
675 a.k.a. "ConneXt". The chip is used in place of the standard
676 PC chipset, so all "standard" peripherals are missing. If this
677 option is selected the kernel will still be able to boot on
678 standard PC machines.
679
Shérab82148d12010-09-25 06:06:57 +0200680config X86_32_IRIS
681 tristate "Eurobraille/Iris poweroff module"
682 depends on X86_32
683 ---help---
684 The Iris machines from EuroBraille do not have APM or ACPI support
685 to shut themselves down properly. A special I/O sequence is
686 needed to do so, which is what this module does at
687 kernel shutdown.
688
689 This is only for Iris machines from EuroBraille.
690
691 If unused, say N.
692
Ingo Molnarae1e9132008-11-11 09:05:16 +0100693config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100694 def_bool y
695 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800696 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100697 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100698 Calculate simpler /proc/<PID>/wchan values. If this option
699 is disabled then wchan values will recurse back to the
700 caller function. This provides more accurate wchan values,
701 at the expense of slightly more scheduling overhead.
702
703 If in doubt, say "Y".
704
Borislav Petkov6276a072013-03-04 21:20:21 +0100705menuconfig HYPERVISOR_GUEST
706 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100707 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100708 Say Y here to enable options for running Linux under various hyper-
709 visors. This option enables basic hypervisor detection and platform
710 setup.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100711
Borislav Petkov6276a072013-03-04 21:20:21 +0100712 If you say N, all options in this submenu will be skipped and
713 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100714
Borislav Petkov6276a072013-03-04 21:20:21 +0100715if HYPERVISOR_GUEST
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100716
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100717config PARAVIRT
718 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100719 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100720 This changes the kernel so it can modify itself when it is run
721 under a hypervisor, potentially improving performance significantly
722 over full virtualization. However, when run without a hypervisor
723 the kernel is theoretically slower and slightly larger.
724
Borislav Petkov6276a072013-03-04 21:20:21 +0100725config PARAVIRT_DEBUG
726 bool "paravirt-ops debugging"
727 depends on PARAVIRT && DEBUG_KERNEL
728 ---help---
729 Enable to debug paravirt_ops internals. Specifically, BUG if
730 a paravirt_op is missing when it is called.
731
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700732config PARAVIRT_SPINLOCKS
733 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700734 depends on PARAVIRT && SMP
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700735 ---help---
736 Paravirtualized spinlocks allow a pvops backend to replace the
737 spinlock implementation with something virtualization-friendly
738 (for example, block the virtual CPU rather than spinning).
739
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530740 It has a minimal impact on native kernels and gives a nice performance
741 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700742
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530743 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700744
Waiman Long45e898b2015-11-09 19:09:25 -0500745config QUEUED_LOCK_STAT
746 bool "Paravirt queued spinlock statistics"
Peter Zijlstracfd89832016-05-18 20:43:02 +0200747 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
Waiman Long45e898b2015-11-09 19:09:25 -0500748 ---help---
749 Enable the collection of statistical data on the slowpath
750 behavior of paravirtualized queued spinlocks and report
751 them on debugfs.
752
Borislav Petkov6276a072013-03-04 21:20:21 +0100753source "arch/x86/xen/Kconfig"
754
755config KVM_GUEST
756 bool "KVM Guest support (including kvmclock)"
757 depends on PARAVIRT
758 select PARAVIRT_CLOCK
759 default y
760 ---help---
761 This option enables various optimizations for running under the KVM
762 hypervisor. It includes a paravirtualized clock, so that instead
763 of relying on a PIT (or probably other) emulation by the
764 underlying device model, the host provides the guest with
765 timing infrastructure such as time of day, and system time
766
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530767config KVM_DEBUG_FS
768 bool "Enable debug information for KVM Guests in debugfs"
769 depends on KVM_GUEST && DEBUG_FS
770 default n
771 ---help---
772 This option enables collection of various statistics for KVM guest.
773 Statistics are displayed in debugfs filesystem. Enabling this option
774 may incur significant overhead.
775
Borislav Petkov6276a072013-03-04 21:20:21 +0100776source "arch/x86/lguest/Kconfig"
777
778config PARAVIRT_TIME_ACCOUNTING
779 bool "Paravirtual steal time accounting"
780 depends on PARAVIRT
781 default n
782 ---help---
783 Select this option to enable fine granularity task steal time
784 accounting. Time spent executing other tasks in parallel with
785 the current vCPU is discounted from the vCPU power. To account for
786 that, there can be a small performance impact.
787
788 If in doubt, say N here.
789
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200790config PARAVIRT_CLOCK
791 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200792
Borislav Petkov6276a072013-03-04 21:20:21 +0100793endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400794
Yinghai Lu08677212010-02-10 01:20:20 -0800795config NO_BOOTMEM
Yinghai Lu774ea0b2010-08-25 13:39:18 -0700796 def_bool y
Yinghai Lu08677212010-02-10 01:20:20 -0800797
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100798source "arch/x86/Kconfig.cpu"
799
800config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100801 def_bool X86_64
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100802 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100803 ---help---
804 Use the IA-PC HPET (High Precision Event Timer) to manage
805 time in preference to the PIT and RTC, if a HPET is
806 present.
807 HPET is the next generation timer replacing legacy 8254s.
808 The HPET provides a stable time base on SMP
809 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200810 as it is off-chip. The interface used is documented
811 in the HPET spec, revision 1.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100812
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100813 You can safely choose Y here. However, HPET will only be
814 activated if the platform and the BIOS support this feature.
815 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100816
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100817 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100818
819config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100820 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800821 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100822
Jacob Panbb24c472009-09-02 07:37:17 -0700823config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000824 def_bool y if X86_INTEL_MID
825 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100826 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000827 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700828 help
829 APB timer is the replacement for 8254, HPET on X86 MID platforms.
830 The APBT provides a stable time base on SMP
831 systems, unlike the TSC, but it is more expensive to access,
832 as it is off-chip. APB timers are always running regardless of CPU
833 C states, they are used as per CPU clockevent device when possible.
834
David Rientjes6a108a12011-01-20 14:44:16 -0800835# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100836# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700837config DMI
838 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800839 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800840 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100841 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700842 Enabled scanning of DMI to identify machine quirks. Say Y
843 here unless you have verified that your setup is not
844 affected by entries in the DMI blacklist. Required by PNP
845 BIOS code.
846
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100847config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700848 bool "Old AMD GART IOMMU support"
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100849 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200850 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100851 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200852 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
853 GART based hardware IOMMUs.
854
855 The GART supports full DMA access for devices with 32-bit access
856 limitations, on systems with more than 3 GB. This is usually needed
857 for USB, sound, many IDE/SATA chipsets and some other devices.
858
859 Newer systems typically have a modern AMD IOMMU, supported via
860 the CONFIG_AMD_IOMMU=y config option.
861
862 In normal configurations this driver is only active when needed:
863 there's more than 3 GB of memory and the system contains a
864 32-bit limited device.
865
866 If unsure, say Y.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100867
868config CALGARY_IOMMU
869 bool "IBM Calgary IOMMU support"
870 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700871 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100872 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100873 Support for hardware IOMMUs in IBM's xSeries x366 and x460
874 systems. Needed to run systems with more than 3GB of memory
875 properly with 32-bit PCI devices that do not support DAC
876 (Double Address Cycle). Calgary also supports bus level
877 isolation, where all DMAs pass through the IOMMU. This
878 prevents them from going anywhere except their intended
879 destination. This catches hard-to-find kernel bugs and
880 mis-behaving drivers and devices that do not use the DMA-API
881 properly to set up their DMA buffers. The IOMMU can be
882 turned off at boot time with the iommu=off parameter.
883 Normally the kernel will make the right choice by itself.
884 If unsure, say Y.
885
886config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100887 def_bool y
888 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100889 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100890 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100891 Should Calgary be enabled by default? if you choose 'y', Calgary
892 will be used (if it exists). If you choose 'n', Calgary will not be
893 used even if it exists. If you choose 'n' and would like to use
894 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
895 If unsure, say Y.
896
897# need this always selected by IOMMU for the VIA workaround
898config SWIOTLB
Joerg Roedela1afd012008-11-18 12:44:21 +0100899 def_bool y if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100900 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100901 Support for software bounce buffers used on x86-64 systems
Joe Millenbach4454d322012-09-02 17:38:20 -0700902 which don't have a hardware IOMMU. Using this PCI devices
903 which can only access 32-bits of memory can be used on systems
904 with more than 3 GB of memory.
905 If unsure, say Y.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100906
FUJITA Tomonoria8522502008-04-29 00:59:36 -0700907config IOMMU_HELPER
Jan Beulich3120e252012-09-10 12:41:45 +0100908 def_bool y
909 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
Linus Torvaldsd25e26b2008-08-25 14:15:38 -0700910
Mike Travis1184dc22008-05-12 21:21:12 +0200911config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200912 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700913 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800914 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100915 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200916 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200917 If unsure, say N.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100918
919config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800920 int "Maximum number of CPUs" if SMP && !MAXSMP
Michael K. Johnson2a3313f2009-04-21 21:44:48 -0400921 range 2 8 if SMP && X86_32 && !X86_BIGSMP
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500922 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
Josh Boyerb53b5ed2013-11-05 09:38:16 -0500923 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
Mike Travis78637a972008-12-16 17:34:00 -0800924 default "1" if !SMP
Josh Boyerb53b5ed2013-11-05 09:38:16 -0500925 default "8192" if MAXSMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800926 default "32" if SMP && X86_BIGSMP
Kirill A. Shutemovc5c19942015-05-08 13:25:45 +0300927 default "8" if SMP && X86_32
928 default "64" if SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100929 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100930 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500931 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +0300932 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100933 minimum value which makes sense is 2.
934
935 This is purely to save memory - each supported CPU adds
936 approximately eight kilobytes to the kernel image.
937
938config SCHED_SMT
Thomas Gleixner4cc15492018-11-25 19:33:37 +0100939 def_bool y if SMP
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100940
941config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100942 def_bool y
943 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +0200944 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100945 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100946 Multi-core scheduler support improves the CPU scheduler's decision
947 making when dealing with multi-core CPU chips at a cost of slightly
948 increased overhead in some places. If unsure say N here.
949
950source "kernel/Kconfig.preempt"
951
Thomas Gleixner30b8b002015-01-15 21:22:39 +0000952config UP_LATE_INIT
953 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +0100954 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +0000955
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100956config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +0000957 bool "Local APIC support on uniprocessors" if !PCI_MSI
958 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +0000959 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100960 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100961 A local APIC (Advanced Programmable Interrupt Controller) is an
962 integrated interrupt controller in the CPU. If you have a single-CPU
963 system which has a processor with a local APIC, you can say Y here to
964 enable and use it. If you say Y here even though your machine doesn't
965 have a local APIC, then the kernel will still run with no slowdown at
966 all. The local APIC supports CPU-generated self-interrupts (timer,
967 performance counters), and the NMI watchdog which detects hard
968 lockups.
969
970config X86_UP_IOAPIC
971 bool "IO-APIC support on uniprocessors"
972 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100973 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100974 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
975 SMP-capable replacement for PC-style interrupt controllers. Most
976 SMP systems and many recent uniprocessor systems have one.
977
978 If you have a single-CPU system with an IO-APIC, you can say Y here
979 to use it. If you say Y here even though your machine doesn't have
980 an IO-APIC, then the kernel will still run with no slowdown at all.
981
982config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100983 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +0200984 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +0800985 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +0800986 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100987
988config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +0000989 def_bool y
990 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100991
Stefan Assmann41b9eb22008-07-15 13:48:55 +0200992config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
993 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +0200994 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100995 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +0200996 This option enables a workaround that fixes a source of
997 spurious interrupts. This is recommended when threaded
998 interrupt handling is used on systems where the generation of
999 superfluous "boot interrupts" cannot be disabled.
1000
1001 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1002 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1003 kernel does during interrupt handling). On chipsets where this
1004 boot IRQ generation cannot be disabled, this workaround keeps
1005 the original IRQ line masked so that only the equivalent "boot
1006 IRQ" is delivered to the CPUs. The workaround also tells the
1007 kernel to set up the IRQ handler on the boot IRQ line. In this
1008 way only one interrupt is delivered to the kernel. Otherwise
1009 the spurious second interrupt may cause the kernel to bring
1010 down (vital) interrupt lines.
1011
1012 Only affects "broken" chipsets. Interrupt sharing may be
1013 increased on these systems.
1014
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001015config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001016 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001017 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001018 default y
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001019 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +02001020 Machine Check support allows the processor to notify the
1021 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001022 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001023 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001024
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001025config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001026 def_bool y
1027 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001028 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001029 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001030 Additional support for intel specific MCE features such as
1031 the thermal monitor.
1032
1033config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001034 def_bool y
1035 prompt "AMD MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001036 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001037 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001038 Additional support for AMD specific MCE features such as
1039 the DRAM Error Threshold.
1040
Andi Kleen4efc0672009-04-28 19:07:31 +02001041config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001042 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001043 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001044 ---help---
1045 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001046 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001047 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001048
Andi Kleenb2762682009-02-12 13:49:31 +01001049config X86_MCE_THRESHOLD
1050 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001051 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001052
Andi Kleenea149b32009-04-29 19:31:00 +02001053config X86_MCE_INJECT
Borislav Petkov10170a92017-01-23 19:35:06 +01001054 depends on X86_MCE && X86_LOCAL_APIC
Andi Kleenea149b32009-04-29 19:31:00 +02001055 tristate "Machine check injector support"
1056 ---help---
1057 Provide support for injecting machine checks for testing purposes.
1058 If you don't know what a machine check is and you don't do kernel
1059 QA it is safe to say n.
1060
Andi Kleen4efc0672009-04-28 19:07:31 +02001061config X86_THERMAL_VECTOR
1062 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001063 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001064
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001065source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001066
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001067config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001068 bool "Legacy VM86 support"
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001069 default n
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001070 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001071 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001072 This option allows user programs to put the CPU into V8086
1073 mode, which is an 80286-era approximation of 16-bit real mode.
1074
1075 Some very old versions of X and/or vbetool require this option
1076 for user mode setting. Similarly, DOSEMU will use it if
1077 available to accelerate real mode DOS programs. However, any
1078 recent version of DOSEMU, X, or vbetool should be fully
1079 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001080 fall back to software emulation. Nevertheless, if you are using
1081 a 16-bit DOS program where 16-bit performance matters, vm86
1082 mode might be faster than emulation and you might want to
1083 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001084
Ingo Molnar1e642812015-09-05 08:58:10 +02001085 Note that any app that works on a 64-bit kernel is unlikely to
1086 need this option, as 64-bit kernels don't, and can't, support
1087 V8086 mode. This option is also unrelated to 16-bit protected
1088 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001089
Ingo Molnar1e642812015-09-05 08:58:10 +02001090 Enabling this option increases the complexity of the kernel
1091 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001092
Ingo Molnar1e642812015-09-05 08:58:10 +02001093 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001094
1095config VM86
1096 bool
1097 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001098
1099config X86_16BIT
1100 bool "Enable support for 16-bit segments" if EXPERT
1101 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001102 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001103 ---help---
1104 This option is required by programs like Wine to run 16-bit
1105 protected mode legacy code on x86 processors. Disabling
1106 this option saves about 300 bytes on i386, or around 6K text
1107 plus 16K runtime memory on x86-64,
1108
1109config X86_ESPFIX32
1110 def_bool y
1111 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001112
H. Peter Anvin197725d2014-05-04 10:00:49 -07001113config X86_ESPFIX64
1114 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001115 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001116
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001117config X86_VSYSCALL_EMULATION
1118 bool "Enable vsyscall emulation" if EXPERT
1119 default y
1120 depends on X86_64
1121 ---help---
1122 This enables emulation of the legacy vsyscall page. Disabling
1123 it is roughly equivalent to booting with vsyscall=none, except
1124 that it will also disable the helpful warning if a program
1125 tries to use a vsyscall. With this option set to N, offending
1126 programs will just segfault, citing addresses of the form
1127 0xffffffffff600?00.
1128
1129 This option is required by many programs built before 2013, and
1130 care should be used even with newer programs if set to N.
1131
1132 Disabling this option saves about 7K of kernel size and
1133 possibly 4K of additional runtime pagetable memory.
1134
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001135config TOSHIBA
1136 tristate "Toshiba Laptop support"
1137 depends on X86_32
1138 ---help---
1139 This adds a driver to safely access the System Management Mode of
1140 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1141 not work on models with a Phoenix BIOS. The System Management Mode
1142 is used to set the BIOS and power saving options on Toshiba portables.
1143
1144 For information on utilities to make use of this driver see the
1145 Toshiba Linux utilities web site at:
1146 <http://www.buzzard.org.uk/toshiba/>.
1147
1148 Say Y if you intend to run this kernel on a Toshiba portable.
1149 Say N otherwise.
1150
1151config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001152 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001153 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001154 select SENSORS_DELL_SMM
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001155 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001156 This option enables legacy /proc/i8k userspace interface in hwmon
1157 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1158 temperature and allows controlling fan speeds of Dell laptops via
1159 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1160 it reports also power and hotkey status. For fan speed control is
1161 needed userspace package i8kutils.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001162
Pali Rohár039ae582015-05-14 13:16:37 +02001163 Say Y if you intend to run this kernel on old Dell laptops or want to
1164 use userspace package i8kutils.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001165 Say N otherwise.
1166
1167config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001168 bool "Enable X86 board specific fixups for reboot"
1169 depends on X86_32
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001170 ---help---
1171 This enables chipset and/or board specific fixups to be done
1172 in order to get reboot to work correctly. This is only needed on
1173 some combinations of hardware and BIOS. The symptom, for which
1174 this config is intended, is when reboot ends with a stalled/hung
1175 system.
1176
1177 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001178 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001179
1180 Say Y if you want to enable the fixup. Currently, it's safe to
1181 enable this option even if you don't need it.
1182 Say N otherwise.
1183
1184config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001185 bool "CPU microcode loading support"
1186 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001187 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001188 select FW_LOADER
1189 ---help---
1190 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001191 Intel and AMD processors. The Intel support is for the IA32 family,
1192 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1193 AMD support is for families 0x10 and later. You will obviously need
1194 the actual microcode binary data itself which is not shipped with
1195 the Linux kernel.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001196
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001197 The preferred method to load microcode from a detached initrd is described
1198 in Documentation/x86/early-microcode.txt. For that you need to enable
1199 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1200 initrd for microcode blobs.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001201
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001202 In addition, you can build-in the microcode into the kernel. For that you
1203 need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode
1204 to the CONFIG_EXTRA_FIRMWARE config option.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001205
Peter Oruba8d86f392008-07-28 18:44:21 +02001206config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001207 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001208 depends on MICROCODE
1209 default MICROCODE
1210 select FW_LOADER
1211 ---help---
1212 This options enables microcode patch loading support for Intel
1213 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001214
Alanb8989db2014-01-20 18:01:56 +00001215 For the current Intel microcode data package go to
1216 <https://downloadcenter.intel.com> and search for
1217 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001218
Peter Oruba80cc9f12008-07-28 18:44:22 +02001219config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001220 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001221 depends on MICROCODE
1222 select FW_LOADER
1223 ---help---
1224 If you select this option, microcode patch loading support for AMD
1225 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001226
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001227config MICROCODE_OLD_INTERFACE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001228 def_bool y
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001229 depends on MICROCODE
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001230
1231config X86_MSR
1232 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001233 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001234 This device gives privileged processes access to the x86
1235 Model-Specific Registers (MSRs). It is a character device with
1236 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1237 MSR accesses are directed to a specific CPU on multi-processor
1238 systems.
1239
1240config X86_CPUID
1241 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001242 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001243 This device gives processes access to the x86 CPUID instruction to
1244 be executed on a specific processor. It is a character device
1245 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1246 /dev/cpu/31/cpuid.
1247
1248choice
1249 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001250 default HIGHMEM4G
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001251 depends on X86_32
1252
1253config NOHIGHMEM
1254 bool "off"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001255 ---help---
1256 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1257 However, the address space of 32-bit x86 processors is only 4
1258 Gigabytes large. That means that, if you have a large amount of
1259 physical memory, not all of it can be "permanently mapped" by the
1260 kernel. The physical memory that's not permanently mapped is called
1261 "high memory".
1262
1263 If you are compiling a kernel which will never run on a machine with
1264 more than 1 Gigabyte total physical RAM, answer "off" here (default
1265 choice and suitable for most users). This will result in a "3GB/1GB"
1266 split: 3GB are mapped so that each process sees a 3GB virtual memory
1267 space and the remaining part of the 4GB virtual memory space is used
1268 by the kernel to permanently map as much physical memory as
1269 possible.
1270
1271 If the machine has between 1 and 4 Gigabytes physical RAM, then
1272 answer "4GB" here.
1273
1274 If more than 4 Gigabytes is used then answer "64GB" here. This
1275 selection turns Intel PAE (Physical Address Extension) mode on.
1276 PAE implements 3-level paging on IA32 processors. PAE is fully
1277 supported by Linux, PAE mode is implemented on all recent Intel
1278 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1279 then the kernel will not boot on CPUs that don't support PAE!
1280
1281 The actual amount of total physical memory will either be
1282 auto detected or can be forced by using a kernel command line option
1283 such as "mem=256M". (Try "man bootparam" or see the documentation of
1284 your boot loader (lilo or loadlin) about how to pass options to the
1285 kernel at boot time.)
1286
1287 If unsure, say "off".
1288
1289config HIGHMEM4G
1290 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001291 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001292 Select this if you have a 32-bit processor and between 1 and 4
1293 gigabytes of physical RAM.
1294
1295config HIGHMEM64G
1296 bool "64GB"
H. Peter Anvineb068e72012-11-28 11:50:23 -08001297 depends on !M486
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001298 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001299 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001300 Select this if you have a 32-bit processor and more than 4
1301 gigabytes of physical RAM.
1302
1303endchoice
1304
1305choice
David Rientjes6a108a12011-01-20 14:44:16 -08001306 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001307 default VMSPLIT_3G
1308 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001309 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001310 Select the desired split between kernel and user memory.
1311
1312 If the address range available to the kernel is less than the
1313 physical memory installed, the remaining memory will be available
1314 as "high memory". Accessing high memory is a little more costly
1315 than low memory, as it needs to be mapped into the kernel first.
1316 Note that increasing the kernel address space limits the range
1317 available to user programs, making the address space there
1318 tighter. Selecting anything other than the default 3G/1G split
1319 will also likely make your kernel incompatible with binary-only
1320 kernel modules.
1321
1322 If you are not absolutely sure what you are doing, leave this
1323 option alone!
1324
1325 config VMSPLIT_3G
1326 bool "3G/1G user/kernel split"
1327 config VMSPLIT_3G_OPT
1328 depends on !X86_PAE
1329 bool "3G/1G user/kernel split (for full 1G low memory)"
1330 config VMSPLIT_2G
1331 bool "2G/2G user/kernel split"
1332 config VMSPLIT_2G_OPT
1333 depends on !X86_PAE
1334 bool "2G/2G user/kernel split (for full 2G low memory)"
1335 config VMSPLIT_1G
1336 bool "1G/3G user/kernel split"
1337endchoice
1338
1339config PAGE_OFFSET
1340 hex
1341 default 0xB0000000 if VMSPLIT_3G_OPT
1342 default 0x80000000 if VMSPLIT_2G
1343 default 0x78000000 if VMSPLIT_2G_OPT
1344 default 0x40000000 if VMSPLIT_1G
1345 default 0xC0000000
1346 depends on X86_32
1347
1348config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001349 def_bool y
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001350 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001351
1352config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001353 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001354 depends on X86_32 && !HIGHMEM4G
Christian Melki9d99c712015-10-05 17:31:33 +02001355 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001356 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001357 PAE is required for NX support, and furthermore enables
1358 larger swapspace support for non-overcommit purposes. It
1359 has the cost of more pagetable lookup overhead, and also
1360 consumes more pagetable space per process.
1361
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001362config ARCH_PHYS_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001363 def_bool y
1364 depends on X86_64 || X86_PAE
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001365
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001366config ARCH_DMA_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001367 def_bool y
1368 depends on X86_64 || HIGHMEM64G
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001369
Ingo Molnar10971ab2015-03-05 08:18:23 +01001370config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001371 def_bool y
1372 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001373 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001374 Certain kernel features effectively disable kernel
1375 linear 1 GB mappings (even if the CPU otherwise
1376 supports them), so don't confuse the user by printing
1377 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001378
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001379# Common NUMA Features
1380config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001381 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001382 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001383 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1384 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001385 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001386 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001387
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001388 The kernel will try to allocate memory used by a CPU on the
1389 local memory controller of the CPU and add some more
1390 NUMA awareness to the kernel.
1391
Ingo Molnarc280ea52008-11-08 13:29:45 +01001392 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001393 (or later), AMD Opteron, or EM64T NUMA.
1394
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001395 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001396 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001397
1398 Otherwise, you should say N.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001399
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001400config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001401 def_bool y
1402 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001403 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001404 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001405 Enable AMD NUMA node topology detection. You should say Y here if
1406 you have a multi processor AMD system. This uses an old method to
1407 read the NUMA configuration directly from the builtin Northbridge
1408 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1409 which also takes priority if both are compiled in.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001410
1411config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001412 def_bool y
1413 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001414 depends on X86_64 && NUMA && ACPI && PCI
1415 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001416 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001417 Enable ACPI SRAT based node topology detection.
1418
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001419# Some NUMA nodes have memory ranges that span
1420# other nodes. Even though a pfn is valid and
1421# between a node's start and end pfns, it may not
1422# reside on that node. See memmap_init_zone()
1423# for details.
1424config NODES_SPAN_OTHER_NODES
1425 def_bool y
1426 depends on X86_64_ACPI_NUMA
1427
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001428config NUMA_EMU
1429 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001430 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001431 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001432 Enable NUMA emulation. A flat machine will be split
1433 into virtual nodes when booted with "numa=fake=N", where N is the
1434 number of nodes. This is only useful for debugging.
1435
1436config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001437 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001438 range 1 10
1439 default "10" if MAXSMP
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001440 default "6" if X86_64
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001441 default "3"
1442 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001443 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001444 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001445 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001446
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001447config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001448 def_bool y
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001449 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001450
1451config NEED_NODE_MEMMAP_SIZE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001452 def_bool y
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001453 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001454
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001455config ARCH_FLATMEM_ENABLE
1456 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001457 depends on X86_32 && !NUMA
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001458
1459config ARCH_DISCONTIGMEM_ENABLE
1460 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001461 depends on NUMA && X86_32
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001462
1463config ARCH_DISCONTIGMEM_DEFAULT
1464 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001465 depends on NUMA && X86_32
1466
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001467config ARCH_SPARSEMEM_ENABLE
1468 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001469 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001470 select SPARSEMEM_STATIC if X86_32
1471 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1472
Tejun Heo3b166512011-04-01 11:15:12 +02001473config ARCH_SPARSEMEM_DEFAULT
1474 def_bool y
1475 depends on X86_64
1476
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001477config ARCH_SELECT_MEMORY_MODEL
1478 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001479 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001480
1481config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001482 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001483 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001484 help
1485 This option enables a sysfs memory/probe interface for testing.
1486 See Documentation/memory-hotplug.txt for more information.
1487 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001488
Tejun Heo3b166512011-04-01 11:15:12 +02001489config ARCH_PROC_KCORE_TEXT
1490 def_bool y
1491 depends on X86_64 && PROC_KCORE
1492
Avi Kivitya29815a2010-01-10 16:28:09 +02001493config ILLEGAL_POINTER_VALUE
1494 hex
1495 default 0 if X86_32
1496 default 0xdead000000000000 if X86_64
1497
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001498source "mm/Kconfig"
1499
Dan Williams7a678322015-08-19 00:34:34 -04001500config X86_PMEM_LEGACY_DEVICE
1501 bool
1502
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001503config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001504 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001505 depends on PHYS_ADDR_T_64BIT
1506 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001507 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001508 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001509 help
1510 Treat memory marked using the non-standard e820 type of 12 as used
1511 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1512 The kernel will offer these regions to the 'pmem' driver so
1513 they can be used for persistent storage.
1514
1515 Say Y if unsure.
1516
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001517config HIGHPTE
1518 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001519 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001520 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001521 The VM uses one page table entry for each page of physical memory.
1522 For systems with a lot of RAM, this can be wasteful of precious
1523 low memory. Setting this option will put user-space page table
1524 entries in high memory.
1525
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001526config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001527 bool "Check for low memory corruption"
1528 ---help---
1529 Periodically check for memory corruption in low memory, which
1530 is suspected to be caused by BIOS. Even when enabled in the
1531 configuration, it is disabled at runtime. Enable it by
1532 setting "memory_corruption_check=1" on the kernel command
1533 line. By default it scans the low 64k of memory every 60
1534 seconds; see the memory_corruption_check_size and
1535 memory_corruption_check_period parameters in
1536 Documentation/kernel-parameters.txt to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001537
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001538 When enabled with the default parameters, this option has
1539 almost no overhead, as it reserves a relatively small amount
1540 of memory and scans it infrequently. It both detects corruption
1541 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001542
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001543 It is, however, intended as a diagnostic tool; if repeatable
1544 BIOS-originated corruption always affects the same memory,
1545 you can use memmap= to prevent the kernel from using that
1546 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001547
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001548config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001549 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001550 depends on X86_CHECK_BIOS_CORRUPTION
1551 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001552 ---help---
1553 Set whether the default state of memory_corruption_check is
1554 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001555
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001556config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001557 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1558 default 64
1559 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001560 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001561 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001562
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001563 The first page contains BIOS data structures that the kernel
1564 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001565
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001566 By default we reserve the first 64K of physical RAM, as a
1567 number of BIOSes are known to corrupt that memory range
1568 during events such as suspend/resume or monitor cable
1569 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001570
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001571 You can set this to 4 if you are absolutely sure that you
1572 trust the BIOS to get all its memory reservations and usages
1573 right. If you know your BIOS have problems beyond the
1574 default 64K area, you can set this to 640 to avoid using the
1575 entire low memory range.
1576
1577 If you have doubts about the BIOS (e.g. suspend/resume does
1578 not work or there's kernel crashes after certain hardware
1579 hotplug events) then you might want to enable
1580 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1581 typical corruption patterns.
1582
1583 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001584
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001585config MATH_EMULATION
1586 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001587 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001588 prompt "Math emulation" if X86_32
1589 ---help---
1590 Linux can emulate a math coprocessor (used for floating point
1591 operations) if you don't have one. 486DX and Pentium processors have
1592 a math coprocessor built in, 486SX and 386 do not, unless you added
1593 a 487DX or 387, respectively. (The messages during boot time can
1594 give you some hints here ["man dmesg"].) Everyone needs either a
1595 coprocessor or this emulation.
1596
1597 If you don't have a math coprocessor, you need to say Y here; if you
1598 say Y here even though you have a coprocessor, the coprocessor will
1599 be used nevertheless. (This behavior can be changed with the kernel
1600 command line option "no387", which comes handy if your coprocessor
1601 is broken. Try "man bootparam" or see the documentation of your boot
1602 loader (lilo or loadlin) about how to pass options to the kernel at
1603 boot time.) This means that it is a good idea to say Y here if you
1604 intend to use this kernel on different machines.
1605
1606 More information about the internals of the Linux math coprocessor
1607 emulation can be found in <file:arch/x86/math-emu/README>.
1608
1609 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1610 kernel, it won't hurt.
1611
1612config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001613 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001614 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001615 ---help---
1616 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1617 the Memory Type Range Registers (MTRRs) may be used to control
1618 processor access to memory ranges. This is most useful if you have
1619 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1620 allows bus write transfers to be combined into a larger transfer
1621 before bursting over the PCI/AGP bus. This can increase performance
1622 of image write operations 2.5 times or more. Saying Y here creates a
1623 /proc/mtrr file which may be used to manipulate your processor's
1624 MTRRs. Typically the X server should use this.
1625
1626 This code has a reasonably generic interface so that similar
1627 control registers on other processors can be easily supported
1628 as well:
1629
1630 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1631 Registers (ARRs) which provide a similar functionality to MTRRs. For
1632 these, the ARRs are used to emulate the MTRRs.
1633 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1634 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1635 write-combining. All of these processors are supported by this code
1636 and it makes sense to say Y here if you have one of them.
1637
1638 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1639 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1640 can lead to all sorts of problems, so it's good to say Y here.
1641
1642 You can safely say Y even if your machine doesn't have MTRRs, you'll
1643 just add about 9 KB to your kernel.
1644
Randy Dunlap7225e752008-07-26 17:54:22 -07001645 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001646
Yinghai Lu95ffa242008-04-29 03:52:33 -07001647config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001648 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001649 prompt "MTRR cleanup support"
1650 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001651 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001652 Convert MTRR layout from continuous to discrete, so X drivers can
1653 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001654
Thomas Gleixneraba37282008-07-15 14:48:48 +02001655 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001656 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001657 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001658
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001659 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001660
1661config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001662 int "MTRR cleanup enable value (0-1)"
1663 range 0 1
1664 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001665 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001666 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001667 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001668
Yinghai Lu12031a62008-05-02 02:40:22 -07001669config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1670 int "MTRR cleanup spare reg num (0-7)"
1671 range 0 7
1672 default "1"
1673 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001674 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001675 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001676 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001677
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001678config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001679 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001680 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001681 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001682 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001683 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001684
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001685 PATs are the modern equivalents of MTRRs and are much more
1686 flexible than MTRRs.
1687
1688 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001689 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001690
1691 If unsure, say Y.
1692
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001693config ARCH_USES_PG_UNCACHED
1694 def_bool y
1695 depends on X86_PAT
1696
H. Peter Anvin628c6242011-07-31 13:59:29 -07001697config ARCH_RANDOM
1698 def_bool y
1699 prompt "x86 architectural random number generator" if EXPERT
1700 ---help---
1701 Enable the x86 architectural RDRAND instruction
1702 (Intel Bull Mountain technology) to generate random numbers.
1703 If supported, this is a high bandwidth, cryptographically
1704 secure hardware random number generator.
1705
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001706config X86_SMAP
1707 def_bool y
1708 prompt "Supervisor Mode Access Prevention" if EXPERT
1709 ---help---
1710 Supervisor Mode Access Prevention (SMAP) is a security
1711 feature in newer Intel processors. There is a small
1712 performance cost if this enabled and turned on; there is
1713 also a small increase in the kernel size if this is enabled.
1714
1715 If unsure, say Y.
1716
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001717config X86_INTEL_MPX
1718 prompt "Intel MPX (Memory Protection Extensions)"
1719 def_bool n
1720 depends on CPU_SUP_INTEL
1721 ---help---
1722 MPX provides hardware features that can be used in
1723 conjunction with compiler-instrumented code to check
1724 memory references. It is designed to detect buffer
1725 overflow or underflow bugs.
1726
1727 This option enables running applications which are
1728 instrumented or otherwise use MPX. It does not use MPX
1729 itself inside the kernel or to protect the kernel
1730 against bad memory references.
1731
1732 Enabling this option will make the kernel larger:
1733 ~8k of kernel text and 36 bytes of data on a 64-bit
1734 defconfig. It adds a long to the 'mm_struct' which
1735 will increase the kernel memory overhead of each
1736 process and adds some branches to paths used during
1737 exec() and munmap().
1738
1739 For details, see Documentation/x86/intel_mpx.txt
1740
1741 If unsure, say N.
1742
Dave Hansen35e97792016-02-12 13:02:00 -08001743config X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001744 prompt "Intel Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001745 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001746 # Note: only available in 64-bit mode
Dave Hansen35e97792016-02-12 13:02:00 -08001747 depends on CPU_SUP_INTEL && X86_64
Dave Hansen284244a2016-02-12 13:02:28 -08001748 ---help---
1749 Memory Protection Keys provides a mechanism for enforcing
1750 page-based protections, but without requiring modification of the
1751 page tables when an application changes protection domains.
1752
1753 For details, see Documentation/x86/protection-keys.txt
1754
1755 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001756
Michal Hocko0fbf0802019-10-23 12:35:50 +02001757choice
1758 prompt "TSX enable mode"
1759 depends on CPU_SUP_INTEL
1760 default X86_INTEL_TSX_MODE_OFF
1761 help
1762 Intel's TSX (Transactional Synchronization Extensions) feature
1763 allows to optimize locking protocols through lock elision which
1764 can lead to a noticeable performance boost.
1765
1766 On the other hand it has been shown that TSX can be exploited
1767 to form side channel attacks (e.g. TAA) and chances are there
1768 will be more of those attacks discovered in the future.
1769
1770 Therefore TSX is not enabled by default (aka tsx=off). An admin
1771 might override this decision by tsx=on the command line parameter.
1772 Even with TSX enabled, the kernel will attempt to enable the best
1773 possible TAA mitigation setting depending on the microcode available
1774 for the particular machine.
1775
1776 This option allows to set the default tsx mode between tsx=on, =off
1777 and =auto. See Documentation/kernel-parameters.txt for more
1778 details.
1779
1780 Say off if not sure, auto if TSX is in use but it should be used on safe
1781 platforms or on if TSX is in use and the security aspect of tsx is not
1782 relevant.
1783
1784config X86_INTEL_TSX_MODE_OFF
1785 bool "off"
1786 help
1787 TSX is disabled if possible - equals to tsx=off command line parameter.
1788
1789config X86_INTEL_TSX_MODE_ON
1790 bool "on"
1791 help
1792 TSX is always enabled on TSX capable HW - equals the tsx=on command
1793 line parameter.
1794
1795config X86_INTEL_TSX_MODE_AUTO
1796 bool "auto"
1797 help
1798 TSX is enabled on TSX capable HW that is believed to be safe against
1799 side channel attacks- equals the tsx=auto command line parameter.
1800endchoice
1801
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001802config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001803 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001804 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001805 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001806 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001807 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001808 This enables the kernel to use EFI runtime services that are
1809 available (such as the EFI variable services).
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001810
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001811 This option is only useful on systems that have EFI firmware.
1812 In addition, you should use the latest ELILO loader available
1813 at <http://elilo.sourceforge.net> in order to take advantage
1814 of EFI runtime services. However, even with this option, the
1815 resultant kernel should continue to boot on existing non-EFI
1816 platforms.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001817
Matt Fleming291f3632011-12-12 21:27:52 +00001818config EFI_STUB
1819 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001820 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001821 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001822 ---help---
1823 This kernel feature allows a bzImage to be loaded directly
1824 by EFI firmware without the use of a bootloader.
1825
Roy Franz4172fe22013-09-22 15:45:25 -07001826 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001827
Matt Fleming7d453ee2014-01-10 18:52:06 +00001828config EFI_MIXED
1829 bool "EFI mixed-mode support"
1830 depends on EFI_STUB && X86_64
1831 ---help---
1832 Enabling this feature allows a 64-bit kernel to be booted
1833 on a 32-bit firmware, provided that your CPU supports 64-bit
1834 mode.
1835
1836 Note that it is not possible to boot a mixed-mode enabled
1837 kernel via the EFI boot stub - a bootloader that supports
1838 the EFI handover protocol must be used.
1839
1840 If unsure, say N.
1841
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001842config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001843 def_bool y
1844 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001845 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001846 This kernel feature is useful for number crunching applications
1847 that may need to compute untrusted bytecode during their
1848 execution. By using pipes or other transports made available to
1849 the process as file descriptors supporting the read/write
1850 syscalls, it's possible to isolate those applications in
1851 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001852 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001853 and the task is only allowed to execute a few safe syscalls
1854 defined by each seccomp mode.
1855
1856 If unsure, say Y. Only embedded should say N here.
1857
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001858source kernel/Kconfig.hz
1859
1860config KEXEC
1861 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001862 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001863 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001864 kexec is a system call that implements the ability to shutdown your
1865 current kernel, and to start another kernel. It is like a reboot
1866 but it is independent of the system firmware. And like a reboot
1867 you can start any kernel with it, not just Linux.
1868
1869 The name comes from the similarity to the exec system call.
1870
1871 It is an ongoing process to be certain the hardware in a machine
1872 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001873 initially work for you. As of this writing the exact hardware
1874 interface is strongly in flux, so no good recommendation can be
1875 made.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001876
Vivek Goyal74ca3172014-08-29 15:18:46 -07001877config KEXEC_FILE
1878 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07001879 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07001880 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07001881 depends on X86_64
1882 depends on CRYPTO=y
1883 depends on CRYPTO_SHA256=y
1884 ---help---
1885 This is new version of kexec system call. This system call is
1886 file based and takes file descriptors as system call argument
1887 for kernel and initramfs as opposed to list of segments as
1888 accepted by previous system call.
1889
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001890config KEXEC_VERIFY_SIG
1891 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07001892 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001893 ---help---
1894 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01001895 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001896
Borislav Petkovd8eb8942015-03-13 14:04:37 +01001897 In addition to that option, you need to enable signature
1898 verification for the corresponding kernel image type being
1899 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001900
1901config KEXEC_BZIMAGE_VERIFY_SIG
1902 bool "Enable bzImage signature verification support"
1903 depends on KEXEC_VERIFY_SIG
1904 depends on SIGNED_PE_FILE_VERIFICATION
1905 select SYSTEM_TRUSTED_KEYRING
1906 ---help---
1907 Enable bzImage signature verification support.
1908
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001909config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02001910 bool "kernel crash dumps"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001911 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001912 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001913 Generate crash dump after being started by kexec.
1914 This should be normally only set in special crash dump kernels
1915 which are loaded in the main kernel with kexec-tools into
1916 a specially reserved region and then later executed after
1917 a crash by kdump/kexec. The crash dump kernel must be compiled
1918 to a memory address not used by the main kernel or BIOS using
1919 PHYSICAL_START, or it must be built as a relocatable image
1920 (CONFIG_RELOCATABLE=y).
1921 For more details see Documentation/kdump/kdump.txt
1922
Huang Ying3ab83522008-07-25 19:45:07 -07001923config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07001924 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08001925 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001926 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07001927 Jump between original kernel and kexeced kernel and invoke
1928 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07001929
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001930config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08001931 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07001932 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001933 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001934 This gives the physical address where the kernel is loaded.
1935
1936 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1937 bzImage will decompress itself to above physical address and
1938 run from there. Otherwise, bzImage will run from the address where
1939 it has been loaded by the boot loader and will ignore above physical
1940 address.
1941
1942 In normal kdump cases one does not have to set/change this option
1943 as now bzImage can be compiled as a completely relocatable image
1944 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1945 address. This option is mainly useful for the folks who don't want
1946 to use a bzImage for capturing the crash dump and want to use a
1947 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1948 to be specifically compiled to run from a specific memory area
1949 (normally a reserved region) and this option comes handy.
1950
H. Peter Anvinceefccc2009-05-11 16:12:16 -07001951 So if you are using bzImage for capturing the crash dump,
1952 leave the value here unchanged to 0x1000000 and set
1953 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1954 for capturing the crash dump change this value to start of
1955 the reserved region. In other words, it can be set based on
1956 the "X" value as specified in the "crashkernel=YM@XM"
1957 command line boot parameter passed to the panic-ed
1958 kernel. Please take a look at Documentation/kdump/kdump.txt
1959 for more details about crash dumps.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001960
1961 Usage of bzImage for capturing the crash dump is recommended as
1962 one does not have to build two kernels. Same kernel can be used
1963 as production kernel and capture kernel. Above option should have
1964 gone away after relocatable bzImage support is introduced. But it
1965 is present because there are users out there who continue to use
1966 vmlinux for dump capture. This option should go away down the
1967 line.
1968
1969 Don't change this unless you know what you are doing.
1970
1971config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07001972 bool "Build a relocatable kernel"
1973 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001974 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001975 This builds a kernel image that retains relocation information
1976 so it can be loaded someplace besides the default 1MB.
1977 The relocations tend to make the kernel binary about 10% larger,
1978 but are discarded at runtime.
1979
1980 One use is for the kexec on panic case where the recovery kernel
1981 must live at a different physical address than the primary
1982 kernel.
1983
1984 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1985 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07001986 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001987
Kees Cook8ab38202013-10-10 17:18:14 -07001988config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07001989 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07001990 depends on RELOCATABLE
Kees Cook8ab38202013-10-10 17:18:14 -07001991 default n
1992 ---help---
Baoquan Hee8581e32016-04-20 13:55:43 -07001993 In support of Kernel Address Space Layout Randomization (KASLR),
1994 this randomizes the physical address at which the kernel image
1995 is decompressed and the virtual address where the kernel
1996 image is mapped, as a security feature that deters exploit
1997 attempts relying on knowledge of the location of kernel
1998 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07001999
Kees Cooked9f0072016-05-25 15:45:33 -07002000 On 64-bit, the kernel physical and virtual addresses are
2001 randomized separately. The physical address will be anywhere
2002 between 16MB and the top of physical memory (up to 64TB). The
2003 virtual address will be randomized from 16MB up to 1GB (9 bits
2004 of entropy). Note that this also reduces the memory space
2005 available to kernel modules from 1.5GB to 1GB.
2006
2007 On 32-bit, the kernel physical and virtual addresses are
2008 randomized together. They will be randomized from 16MB up to
2009 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002010
Baoquan Hee8581e32016-04-20 13:55:43 -07002011 Entropy is generated using the RDRAND instruction if it is
2012 supported. If RDTSC is supported, its value is mixed into
2013 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002014 supported, then entropy is read from the i8254 timer. The
2015 usable entropy is limited by the kernel being built using
2016 2GB addressing, and that PHYSICAL_ALIGN must be at a
2017 minimum of 2MB. As a result, only 10 bits of entropy are
2018 theoretically possible, but the implementations are further
2019 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002020
Baoquan Hee8581e32016-04-20 13:55:43 -07002021 If CONFIG_HIBERNATE is also enabled, KASLR is disabled at boot
2022 time. To enable it, boot with "kaslr" on the kernel command
2023 line (which will also disable hibernation).
Kees Cook6145cfe2013-10-10 17:18:18 -07002024
Baoquan Hee8581e32016-04-20 13:55:43 -07002025 If unsure, say N.
Kees Cook8ab38202013-10-10 17:18:14 -07002026
2027# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002028config X86_NEED_RELOCS
2029 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002030 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002031
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002032config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002033 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002034 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002035 range 0x2000 0x1000000 if X86_32
2036 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002037 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002038 This value puts the alignment restrictions on physical address
2039 where kernel is loaded and run from. Kernel is compiled for an
2040 address which meets above alignment restriction.
2041
2042 If bootloader loads the kernel at a non-aligned address and
2043 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2044 address aligned to above value and run from there.
2045
2046 If bootloader loads the kernel at a non-aligned address and
2047 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2048 load address and decompress itself to the address it has been
2049 compiled for and run from there. The address for which kernel is
2050 compiled already meets above alignment restrictions. Hence the
2051 end result is that kernel runs from a physical address meeting
2052 above alignment restrictions.
2053
Kees Cooka0215062013-07-08 09:15:17 -07002054 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2055 this value must be a multiple of 0x200000.
2056
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002057 Don't change this unless you know what you are doing.
2058
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002059config RANDOMIZE_MEMORY
2060 bool "Randomize the kernel memory sections"
2061 depends on X86_64
2062 depends on RANDOMIZE_BASE
2063 default RANDOMIZE_BASE
2064 ---help---
2065 Randomizes the base virtual address of kernel memory sections
2066 (physical memory mapping, vmalloc & vmemmap). This security feature
2067 makes exploits relying on predictable memory locations less reliable.
2068
2069 The order of allocations remains unchanged. Entropy is generated in
2070 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2071 configuration have in average 30,000 different possible virtual
2072 addresses for each memory section.
2073
2074 If unsure, say N.
2075
Thomas Garnier90397a42016-06-21 17:47:06 -07002076config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2077 hex "Physical memory mapping padding" if EXPERT
2078 depends on RANDOMIZE_MEMORY
2079 default "0xa" if MEMORY_HOTPLUG
2080 default "0x0"
2081 range 0x1 0x40 if MEMORY_HOTPLUG
2082 range 0x0 0x40
2083 ---help---
2084 Define the padding in terabytes added to the existing physical
2085 memory size during kernel memory randomization. It is useful
2086 for memory hotplug support but reduces the entropy available for
2087 address randomization.
2088
2089 If unsure, leave at the default value.
2090
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002091config HOTPLUG_CPU
Thomas Gleixner6e9a7142019-03-26 17:36:06 +01002092 def_bool y
Stephen Rothwell40b31362013-05-21 13:49:35 +10002093 depends on SMP
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002094
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002095config BOOTPARAM_HOTPLUG_CPU0
2096 bool "Set default setting of cpu0_hotpluggable"
2097 default n
Kees Cook2c922cd2013-01-22 13:01:19 -08002098 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002099 ---help---
2100 Set whether default state of cpu0_hotpluggable is on or off.
2101
2102 Say Y here to enable CPU0 hotplug by default. If this switch
2103 is turned on, there is no need to give cpu0_hotplug kernel
2104 parameter and the CPU0 hotplug feature is enabled by default.
2105
2106 Please note: there are two known CPU0 dependencies if you want
2107 to enable the CPU0 hotplug feature either by this switch or by
2108 cpu0_hotplug kernel parameter.
2109
2110 First, resume from hibernate or suspend always starts from CPU0.
2111 So hibernate and suspend are prevented if CPU0 is offline.
2112
2113 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2114 offline if any interrupt can not migrate out of CPU0. There may
2115 be other CPU0 dependencies.
2116
2117 Please make sure the dependencies are under your control before
2118 you enable this feature.
2119
2120 Say N if you don't want to enable CPU0 hotplug feature by default.
2121 You still can enable the CPU0 hotplug feature at boot by kernel
2122 parameter cpu0_hotplug.
2123
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002124config DEBUG_HOTPLUG_CPU0
2125 def_bool n
2126 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002127 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002128 ---help---
2129 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2130 soon as possible and boots up userspace with CPU0 offlined. User
2131 can online CPU0 back after boot time.
2132
2133 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2134 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2135 compilation or giving cpu0_hotplug kernel parameter at boot.
2136
2137 If unsure, say N.
2138
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002139config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002140 def_bool n
2141 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Roland McGrathaf65d642008-01-30 13:30:43 +01002142 depends on X86_32 || IA32_EMULATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002143 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002144 Certain buggy versions of glibc will crash if they are
2145 presented with a 32-bit vDSO that is not mapped at the address
2146 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002147
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002148 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2149 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2150 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2151 the only released version with the bug, but OpenSUSE 9
2152 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002153
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002154 The symptom of the bug is that everything crashes on startup, saying:
2155 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2156
2157 Saying Y here changes the default value of the vdso32 boot
2158 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2159 This works around the glibc bug but hurts performance.
2160
2161 If unsure, say N: if you are compiling your own kernel, you
2162 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002163
Kees Cook3dc33bd2015-08-12 17:55:19 -07002164choice
2165 prompt "vsyscall table for legacy applications"
2166 depends on X86_64
2167 default LEGACY_VSYSCALL_EMULATE
2168 help
2169 Legacy user code that does not know how to find the vDSO expects
2170 to be able to issue three syscalls by calling fixed addresses in
2171 kernel space. Since this location is not randomized with ASLR,
2172 it can be used to assist security vulnerability exploitation.
2173
2174 This setting can be changed at boot time via the kernel command
2175 line parameter vsyscall=[native|emulate|none].
2176
2177 On a system with recent enough glibc (2.14 or newer) and no
2178 static binaries, you can say None without a performance penalty
2179 to improve security.
2180
2181 If unsure, select "Emulate".
2182
2183 config LEGACY_VSYSCALL_NATIVE
2184 bool "Native"
2185 help
2186 Actual executable code is located in the fixed vsyscall
2187 address mapping, implementing time() efficiently. Since
2188 this makes the mapping executable, it can be used during
2189 security vulnerability exploitation (traditionally as
2190 ROP gadgets). This configuration is not recommended.
2191
2192 config LEGACY_VSYSCALL_EMULATE
2193 bool "Emulate"
2194 help
2195 The kernel traps and emulates calls into the fixed
2196 vsyscall address mapping. This makes the mapping
2197 non-executable, but it still contains known contents,
2198 which could be used in certain rare security vulnerability
2199 exploits. This configuration is recommended when userspace
2200 still uses the vsyscall area.
2201
2202 config LEGACY_VSYSCALL_NONE
2203 bool "None"
2204 help
2205 There will be no vsyscall mapping at all. This will
2206 eliminate any risk of ASLR bypass due to the vsyscall
2207 fixed address mapping. Attempts to use the vsyscalls
2208 will be reported to dmesg, so that either old or
2209 malicious userspace programs can be identified.
2210
2211endchoice
2212
Tim Bird516cbf32008-08-12 12:52:36 -07002213config CMDLINE_BOOL
2214 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002215 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002216 Allow for specifying boot arguments to the kernel at
2217 build time. On some systems (e.g. embedded ones), it is
2218 necessary or convenient to provide some or all of the
2219 kernel boot arguments with the kernel itself (that is,
2220 to not rely on the boot loader to provide them.)
2221
2222 To compile command line arguments into the kernel,
2223 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002224 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002225
2226 Systems with fully functional boot loaders (i.e. non-embedded)
2227 should leave this option set to 'N'.
2228
2229config CMDLINE
2230 string "Built-in kernel command string"
2231 depends on CMDLINE_BOOL
2232 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002233 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002234 Enter arguments here that should be compiled into the kernel
2235 image and used at boot time. If the boot loader provides a
2236 command line at boot time, it is appended to this string to
2237 form the full kernel command line, when the system boots.
2238
2239 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2240 change this behavior.
2241
2242 In most cases, the command line (whether built-in or provided
2243 by the boot loader) should specify the device for the root
2244 file system.
2245
2246config CMDLINE_OVERRIDE
2247 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002248 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002249 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002250 Set this option to 'Y' to have the kernel ignore the boot loader
2251 command line, and use ONLY the built-in command line.
2252
2253 This is used to work around broken boot loaders. This should
2254 be set to 'N' under normal conditions.
2255
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002256config MODIFY_LDT_SYSCALL
2257 bool "Enable the LDT (local descriptor table)" if EXPERT
2258 default y
2259 ---help---
2260 Linux can allow user programs to install a per-process x86
2261 Local Descriptor Table (LDT) using the modify_ldt(2) system
2262 call. This is required to run 16-bit or segmented code such as
2263 DOSEMU or some Wine programs. It is also used by some very old
2264 threading libraries.
2265
2266 Enabling this feature adds a small amount of overhead to
2267 context switches and increases the low-level kernel attack
2268 surface. Disabling it removes the modify_ldt(2) system call.
2269
2270 Saying 'N' here may make sense for embedded or server kernels.
2271
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002272source "kernel/livepatch/Kconfig"
2273
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002274endmenu
2275
2276config ARCH_ENABLE_MEMORY_HOTPLUG
2277 def_bool y
2278 depends on X86_64 || (X86_32 && HIGHMEM)
2279
Gary Hade35551052008-10-31 10:52:03 -07002280config ARCH_ENABLE_MEMORY_HOTREMOVE
2281 def_bool y
2282 depends on MEMORY_HOTPLUG
2283
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002284config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002285 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002286 depends on NUMA
2287
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002288config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2289 def_bool y
2290 depends on X86_64 || X86_PAE
2291
Naoya Horiguchic177c812014-06-04 16:05:35 -07002292config ARCH_ENABLE_HUGEPAGE_MIGRATION
2293 def_bool y
2294 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2295
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002296menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002297
2298config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002299 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002300 depends on X86_64 && HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002301
2302source "kernel/power/Kconfig"
2303
2304source "drivers/acpi/Kconfig"
2305
Feng Tangefafc8b2009-08-14 15:23:29 -04002306source "drivers/sfi/Kconfig"
2307
Andi Kleena6b68072008-01-30 13:32:49 +01002308config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002309 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002310 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002311
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002312menuconfig APM
2313 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002314 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002315 ---help---
2316 APM is a BIOS specification for saving power using several different
2317 techniques. This is mostly useful for battery powered laptops with
2318 APM compliant BIOSes. If you say Y here, the system time will be
2319 reset after a RESUME operation, the /proc/apm device will provide
2320 battery status information, and user-space programs will receive
2321 notification of APM "events" (e.g. battery status change).
2322
2323 If you select "Y" here, you can disable actual use of the APM
2324 BIOS by passing the "apm=off" option to the kernel at boot time.
2325
2326 Note that the APM support is almost completely disabled for
2327 machines with more than one CPU.
2328
2329 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002330 and more information, read <file:Documentation/power/apm-acpi.txt>
2331 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002332 <http://www.tldp.org/docs.html#howto>.
2333
2334 This driver does not spin down disk drives (see the hdparm(8)
2335 manpage ("man 8 hdparm") for that), and it doesn't turn off
2336 VESA-compliant "green" monitors.
2337
2338 This driver does not support the TI 4000M TravelMate and the ACER
2339 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2340 desktop machines also don't have compliant BIOSes, and this driver
2341 may cause those machines to panic during the boot phase.
2342
2343 Generally, if you don't have a battery in your machine, there isn't
2344 much point in using this driver and you should say N. If you get
2345 random kernel OOPSes or reboots that don't seem to be related to
2346 anything, try disabling/enabling this option (or disabling/enabling
2347 APM in your BIOS).
2348
2349 Some other things you should try when experiencing seemingly random,
2350 "weird" problems:
2351
2352 1) make sure that you have enough swap space and that it is
2353 enabled.
2354 2) pass the "no-hlt" option to the kernel
2355 3) switch on floating point emulation in the kernel and pass
2356 the "no387" option to the kernel
2357 4) pass the "floppy=nodma" option to the kernel
2358 5) pass the "mem=4M" option to the kernel (thereby disabling
2359 all but the first 4 MB of RAM)
2360 6) make sure that the CPU is not over clocked.
2361 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2362 8) disable the cache from your BIOS settings
2363 9) install a fan for the video card or exchange video RAM
2364 10) install a better fan for the CPU
2365 11) exchange RAM chips
2366 12) exchange the motherboard.
2367
2368 To compile this driver as a module, choose M here: the
2369 module will be called apm.
2370
2371if APM
2372
2373config APM_IGNORE_USER_SUSPEND
2374 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002375 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002376 This option will ignore USER SUSPEND requests. On machines with a
2377 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2378 series notebooks, it is necessary to say Y because of a BIOS bug.
2379
2380config APM_DO_ENABLE
2381 bool "Enable PM at boot time"
2382 ---help---
2383 Enable APM features at boot time. From page 36 of the APM BIOS
2384 specification: "When disabled, the APM BIOS does not automatically
2385 power manage devices, enter the Standby State, enter the Suspend
2386 State, or take power saving steps in response to CPU Idle calls."
2387 This driver will make CPU Idle calls when Linux is idle (unless this
2388 feature is turned off -- see "Do CPU IDLE calls", below). This
2389 should always save battery power, but more complicated APM features
2390 will be dependent on your BIOS implementation. You may need to turn
2391 this option off if your computer hangs at boot time when using APM
2392 support, or if it beeps continuously instead of suspending. Turn
2393 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2394 T400CDT. This is off by default since most machines do fine without
2395 this feature.
2396
2397config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002398 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002399 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002400 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002401 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2402 On some machines, this can activate improved power savings, such as
2403 a slowed CPU clock rate, when the machine is idle. These idle calls
2404 are made after the idle loop has run for some length of time (e.g.,
2405 333 mS). On some machines, this will cause a hang at boot time or
2406 whenever the CPU becomes idle. (On machines with more than one CPU,
2407 this option does nothing.)
2408
2409config APM_DISPLAY_BLANK
2410 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002411 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002412 Enable console blanking using the APM. Some laptops can use this to
2413 turn off the LCD backlight when the screen blanker of the Linux
2414 virtual console blanks the screen. Note that this is only used by
2415 the virtual console screen blanker, and won't turn off the backlight
2416 when using the X Window system. This also doesn't have anything to
2417 do with your VESA-compliant power-saving monitor. Further, this
2418 option doesn't work for all laptops -- it might not turn off your
2419 backlight at all, or it might print a lot of errors to the console,
2420 especially if you are using gpm.
2421
2422config APM_ALLOW_INTS
2423 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002424 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002425 Normally we disable external interrupts while we are making calls to
2426 the APM BIOS as a measure to lessen the effects of a badly behaving
2427 BIOS implementation. The BIOS should reenable interrupts if it
2428 needs to. Unfortunately, some BIOSes do not -- especially those in
2429 many of the newer IBM Thinkpads. If you experience hangs when you
2430 suspend, try setting this to Y. Otherwise, say N.
2431
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002432endif # APM
2433
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002434source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002435
2436source "drivers/cpuidle/Kconfig"
2437
Andy Henroid27471fd2008-10-09 11:45:22 -07002438source "drivers/idle/Kconfig"
2439
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002440endmenu
2441
2442
2443menu "Bus options (PCI etc.)"
2444
2445config PCI
Ingo Molnar1ac97012008-05-19 14:10:14 +02002446 bool "PCI support"
Adrian Bunk1c858082008-01-30 13:32:32 +01002447 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002448 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002449 Find out whether you have a PCI motherboard. PCI is the name of a
2450 bus system, i.e. the way the CPU talks to the other stuff inside
2451 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2452 VESA. If you have PCI, say Y, otherwise N.
2453
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002454choice
2455 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002456 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002457 default PCI_GOANY
2458 ---help---
2459 On PCI systems, the BIOS can be used to detect the PCI devices and
2460 determine their configuration. However, some old PCI motherboards
2461 have BIOS bugs and may crash if this is done. Also, some embedded
2462 PCI-based systems don't have any BIOS at all. Linux can also try to
2463 detect the PCI hardware directly without using the BIOS.
2464
2465 With this option, you can specify how Linux should detect the
2466 PCI devices. If you choose "BIOS", the BIOS will be used,
2467 if you choose "Direct", the BIOS won't be used, and if you
2468 choose "MMConfig", then PCI Express MMCONFIG will be used.
2469 If you choose "Any", the kernel will try MMCONFIG, then the
2470 direct access method and falls back to the BIOS if that doesn't
2471 work. If unsure, go with the default, which is "Any".
2472
2473config PCI_GOBIOS
2474 bool "BIOS"
2475
2476config PCI_GOMMCONFIG
2477 bool "MMConfig"
2478
2479config PCI_GODIRECT
2480 bool "Direct"
2481
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002482config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002483 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002484 depends on OLPC
2485
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002486config PCI_GOANY
2487 bool "Any"
2488
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002489endchoice
2490
2491config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002492 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002493 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002494
2495# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2496config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002497 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002498 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002499
2500config PCI_MMCONFIG
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002501 def_bool y
Feng Tang5f0db7a2009-08-14 15:37:50 -04002502 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002503
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002504config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002505 def_bool y
2506 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002507
Alex Nixonb5401a92010-03-18 16:31:34 -04002508config PCI_XEN
2509 def_bool y
2510 depends on PCI && XEN
2511 select SWIOTLB_XEN
2512
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002513config PCI_DOMAINS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002514 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002515 depends on PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002516
2517config PCI_MMCONFIG
2518 bool "Support mmconfig PCI config space access"
2519 depends on X86_64 && PCI && ACPI
2520
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002521config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002522 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002523 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002524 help
2525 Read the PCI windows out of the CNB20LE host bridge. This allows
2526 PCI hotplug to work on systems with the CNB20LE chipset which do
2527 not have ACPI.
2528
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002529 There's no public spec for this chipset, and this functionality
2530 is known to be incomplete.
2531
2532 You should say N unless you know you need this.
2533
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002534source "drivers/pci/Kconfig"
2535
William Breathitt Gray3a495512016-05-27 18:08:27 -04002536config ISA_BUS
2537 bool "ISA-style bus support on modern systems" if EXPERT
2538 select ISA_BUS_API
2539 help
2540 Enables ISA-style drivers on modern systems. This is necessary to
2541 support PC/104 devices on X86_64 platforms.
2542
2543 If unsure, say N.
2544
David Rientjes1c00f012011-03-22 16:34:59 -07002545# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002546config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002547 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2548 default y
2549 help
2550 Enables ISA-style DMA support for devices requiring such controllers.
2551 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002552
Linus Torvalds51e68d02016-05-21 10:25:19 -07002553if X86_32
2554
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002555config ISA
2556 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002557 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002558 Find out whether you have ISA slots on your motherboard. ISA is the
2559 name of a bus system, i.e. the way the CPU talks to the other stuff
2560 inside your box. Other bus systems are PCI, EISA, MicroChannel
2561 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2562 newer boards don't support it. If you have ISA, say Y, otherwise N.
2563
2564config EISA
2565 bool "EISA support"
2566 depends on ISA
2567 ---help---
2568 The Extended Industry Standard Architecture (EISA) bus was
2569 developed as an open alternative to the IBM MicroChannel bus.
2570
2571 The EISA bus provided some of the features of the IBM MicroChannel
2572 bus while maintaining backward compatibility with cards made for
2573 the older ISA bus. The EISA bus saw limited use between 1988 and
2574 1995 when it was made obsolete by the PCI bus.
2575
2576 Say Y here if you are building a kernel for an EISA-based machine.
2577
2578 Otherwise, say N.
2579
2580source "drivers/eisa/Kconfig"
2581
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002582config SCx200
2583 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002584 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002585 This provides basic support for National Semiconductor's
2586 (now AMD's) Geode processors. The driver probes for the
2587 PCI-IDs of several on-chip devices, so its a good dependency
2588 for other scx200_* drivers.
2589
2590 If compiled as a module, the driver is named scx200.
2591
2592config SCx200HR_TIMER
2593 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002594 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002595 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002596 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002597 This driver provides a clocksource built upon the on-chip
2598 27MHz high-resolution timer. Its also a workaround for
2599 NSC Geode SC-1100's buggy TSC, which loses time when the
2600 processor goes idle (as is done by the scheduler). The
2601 other workaround is idle=poll boot option.
2602
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002603config OLPC
2604 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002605 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002606 select GPIOLIB
Thomas Gleixnerdc3119e72011-02-23 10:08:31 +01002607 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002608 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002609 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002610 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002611 Add support for detecting the unique features of the OLPC
2612 XO hardware.
2613
Daniel Drakea3128582011-06-25 17:34:10 +01002614config OLPC_XO1_PM
2615 bool "OLPC XO-1 Power Management"
Daniel Drake97c4cb72011-06-25 17:34:11 +01002616 depends on OLPC && MFD_CS5535 && PM_SLEEP
Daniel Drakea3128582011-06-25 17:34:10 +01002617 select MFD_CORE
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002618 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002619 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002620
Daniel Drakecfee9592011-06-25 17:34:17 +01002621config OLPC_XO1_RTC
2622 bool "OLPC XO-1 Real Time Clock"
2623 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2624 ---help---
2625 Add support for the XO-1 real time clock, which can be used as a
2626 programmable wakeup source.
2627
Daniel Drake7feda8e2011-06-25 17:34:12 +01002628config OLPC_XO1_SCI
2629 bool "OLPC XO-1 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002630 depends on OLPC && OLPC_XO1_PM
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002631 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002632 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002633 select GPIO_CS5535
2634 select MFD_CORE
2635 ---help---
2636 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002637 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002638 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002639 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002640 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002641 - AC adapter status updates
2642 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002643
Daniel Drakea0f30f52011-06-25 17:34:18 +01002644config OLPC_XO15_SCI
2645 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002646 depends on OLPC && ACPI
2647 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002648 ---help---
2649 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2650 - EC-driven system wakeups
2651 - AC adapter status updates
2652 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002653
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002654config ALIX
2655 bool "PCEngines ALIX System Support (LED setup)"
2656 select GPIOLIB
2657 ---help---
2658 This option enables system support for the PCEngines ALIX.
2659 At present this just sets up LEDs for GPIO control on
2660 ALIX2/3/6 boards. However, other system specific setup should
2661 get added here.
2662
2663 Note: You must still enable the drivers for GPIO and LED support
2664 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2665
2666 Note: You have to set alix.force=1 for boards with Award BIOS.
2667
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002668config NET5501
2669 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2670 select GPIOLIB
2671 ---help---
2672 This option enables system support for the Soekris Engineering net5501.
2673
Philip A. Prindeville31970592012-01-14 01:45:39 -07002674config GEOS
2675 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2676 select GPIOLIB
2677 depends on DMI
2678 ---help---
2679 This option enables system support for the Traverse Technologies GEOS.
2680
Vivien Didelot7d029122013-01-04 16:18:14 -05002681config TS5500
2682 bool "Technologic Systems TS-5500 platform support"
2683 depends on MELAN
2684 select CHECK_SIGNATURE
2685 select NEW_LEDS
2686 select LEDS_CLASS
2687 ---help---
2688 This option enables system support for the Technologic Systems TS-5500.
2689
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002690endif # X86_32
2691
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002692config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002693 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002694 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002695
2696source "drivers/pcmcia/Kconfig"
2697
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002698config RAPIDIO
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002699 tristate "RapidIO support"
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002700 depends on PCI
2701 default n
2702 help
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002703 If enabled this option will include drivers and the core
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002704 infrastructure code to support RapidIO interconnect devices.
2705
2706source "drivers/rapidio/Kconfig"
2707
David Herrmanne3263ab2013-08-02 14:05:22 +02002708config X86_SYSFB
2709 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2710 help
2711 Firmwares often provide initial graphics framebuffers so the BIOS,
2712 bootloader or kernel can show basic video-output during boot for
2713 user-guidance and debugging. Historically, x86 used the VESA BIOS
2714 Extensions and EFI-framebuffers for this, which are mostly limited
2715 to x86.
2716 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2717 framebuffers so the new generic system-framebuffer drivers can be
2718 used on x86. If the framebuffer is not compatible with the generic
2719 modes, it is adverticed as fallback platform framebuffer so legacy
2720 drivers like efifb, vesafb and uvesafb can pick it up.
2721 If this option is not selected, all system framebuffers are always
2722 marked as fallback platform framebuffers as usual.
2723
2724 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2725 not be able to pick up generic system framebuffers if this option
2726 is selected. You are highly encouraged to enable simplefb as
2727 replacement if you select this option. simplefb can correctly deal
2728 with generic system framebuffers. But you should still keep vesafb
2729 and others enabled as fallback if a system framebuffer is
2730 incompatible with simplefb.
2731
2732 If unsure, say Y.
2733
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002734endmenu
2735
2736
2737menu "Executable file formats / Emulations"
2738
2739source "fs/Kconfig.binfmt"
2740
2741config IA32_EMULATION
2742 bool "IA32 Emulation"
2743 depends on X86_64
Randy Dunlapd1603992013-06-18 12:33:40 -07002744 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002745 select COMPAT_BINFMT_ELF
Brian Gerst3bead552015-06-22 07:55:19 -04002746 select ARCH_WANT_OLD_COMPAT_IPC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002747 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002748 Include code to run legacy 32-bit programs under a
2749 64-bit kernel. You should likely turn this on, unless you're
2750 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002751
2752config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002753 tristate "IA32 a.out support"
2754 depends on IA32_EMULATION
2755 ---help---
2756 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002757
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002758config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002759 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002760 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002761 ---help---
2762 Include code to run binaries for the x32 native 32-bit ABI
2763 for 64-bit processors. An x32 process gets access to the
2764 full 64-bit register file and wide data path while leaving
2765 pointers at 32 bits for smaller memory footprint.
2766
2767 You will need a recent binutils (2.22 or later) with
2768 elf32_x86_64 support enabled to compile a kernel with this
2769 option set.
2770
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002771config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002772 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002773 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002774
Jan Beulich3120e252012-09-10 12:41:45 +01002775if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002776config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002777 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002778
2779config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002780 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002781 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002782endif
David Howellsee009e4a02011-03-07 15:06:20 +00002783
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002784endmenu
2785
2786
Keith Packarde5beae12008-11-03 18:21:45 +01002787config HAVE_ATOMIC_IOMAP
2788 def_bool y
2789 depends on X86_32
2790
Alessandro Rubini4692d772012-04-04 19:39:58 +02002791config X86_DEV_DMA_OPS
2792 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002793 depends on X86_64 || STA2X11
Alessandro Rubini4692d772012-04-04 19:39:58 +02002794
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002795config X86_DMA_REMAP
2796 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002797 depends on STA2X11
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002798
Li, Aubrey93e5ead2014-06-30 14:08:42 +08002799config PMC_ATOM
2800 def_bool y
2801 depends on PCI
2802
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002803source "net/Kconfig"
2804
2805source "drivers/Kconfig"
2806
2807source "drivers/firmware/Kconfig"
2808
2809source "fs/Kconfig"
2810
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002811source "arch/x86/Kconfig.debug"
2812
2813source "security/Kconfig"
2814
2815source "crypto/Kconfig"
2816
Avi Kivityedf88412007-12-16 11:02:48 +02002817source "arch/x86/kvm/Kconfig"
2818
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002819source "lib/Kconfig"