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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
22 select ANON_INODES
23 select ARCH_CLOCKSOURCE_DATA
24 select ARCH_DISCARD_MEMBLOCK
25 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
Stephen Boyd446f24d2013-04-30 15:28:42 -070026 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
Dan Williams21266be2015-11-19 18:19:29 -080027 select ARCH_HAS_DEVMEM_IS_ALLOWED
Ingo Molnar6471b822015-06-03 10:00:13 +020028 select ARCH_HAS_ELF_RANDOMIZE
Linus Torvalds72d93102014-09-13 11:14:53 -070029 select ARCH_HAS_FAST_MULTIPLIER
Riku Voipio957e3fa2014-12-12 16:57:44 -080030 select ARCH_HAS_GCOV_PROFILE_ALL
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
Mel Gorman72b252a2015-09-04 15:47:32 -070047 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP
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
51 select ARCH_WANT_OPTIONAL_GPIOLIB
52 select BUILDTIME_EXTABLE_SORT
53 select CLKEVT_I8253
54 select CLKSRC_I8253 if X86_32
55 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
56 select CLOCKSOURCE_WATCHDOG
57 select CLONE_BACKWARDS if X86_32
58 select COMPAT_OLD_SIGACTION if IA32_EMULATION
59 select DCACHE_WORD_ACCESS
Linus Torvalds45471cd2015-06-24 19:52:06 -070060 select EDAC_ATOMIC_SCRUB
61 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +020062 select GENERIC_CLOCKEVENTS
63 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
64 select GENERIC_CLOCKEVENTS_MIN_ADJUST
65 select GENERIC_CMOS_UPDATE
66 select GENERIC_CPU_AUTOPROBE
67 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
82 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
83 select HAVE_ARCH_JUMP_LABEL
84 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
85 select HAVE_ARCH_KGDB
86 select HAVE_ARCH_KMEMCHECK
Daniel Cashman9e08f572016-01-14 15:20:06 -080087 select HAVE_ARCH_MMAP_RND_BITS if MMU
88 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Ingo Molnar6471b822015-06-03 10:00:13 +020089 select HAVE_ARCH_SECCOMP_FILTER
90 select HAVE_ARCH_SOFT_DIRTY if X86_64
91 select HAVE_ARCH_TRACEHOOK
92 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
93 select HAVE_BPF_JIT if X86_64
94 select HAVE_CC_STACKPROTECTOR
95 select HAVE_CMPXCHG_DOUBLE
96 select HAVE_CMPXCHG_LOCAL
97 select HAVE_CONTEXT_TRACKING if X86_64
Josh Triplettc1bd55f2015-06-30 15:00:00 -070098 select HAVE_COPY_THREAD_TLS
Ingo Molnar6471b822015-06-03 10:00:13 +020099 select HAVE_C_RECORDMCOUNT
100 select HAVE_DEBUG_KMEMLEAK
101 select HAVE_DEBUG_STACKOVERFLOW
102 select HAVE_DMA_API_DEBUG
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700103 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400104 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900105 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Johannes Berg58340a02008-07-25 01:45:33 -0700106 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Ingo Molnar6471b822015-06-03 10:00:13 +0200107 select HAVE_FENTRY if X86_64
108 select HAVE_FTRACE_MCOUNT_RECORD
109 select HAVE_FUNCTION_GRAPH_FP_TEST
110 select HAVE_FUNCTION_GRAPH_TRACER
111 select HAVE_FUNCTION_TRACER
112 select HAVE_GENERIC_DMA_COHERENT if X86_32
K.Prasad0067f122009-06-01 23:43:57 +0530113 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200114 select HAVE_IDE
115 select HAVE_IOREMAP_PROT
116 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
117 select HAVE_IRQ_TIME_ACCOUNTING
118 select HAVE_KERNEL_BZIP2
119 select HAVE_KERNEL_GZIP
120 select HAVE_KERNEL_LZ4
121 select HAVE_KERNEL_LZMA
122 select HAVE_KERNEL_LZO
123 select HAVE_KERNEL_XZ
124 select HAVE_KPROBES
125 select HAVE_KPROBES_ON_FTRACE
126 select HAVE_KRETPROBES
127 select HAVE_KVM
128 select HAVE_LIVEPATCH if X86_64
129 select HAVE_MEMBLOCK
130 select HAVE_MEMBLOCK_NODE_MAP
Frederic Weisbecker01027522010-04-11 18:55:56 +0200131 select HAVE_MIXED_BREAKPOINTS_REGS
Ingo Molnar6471b822015-06-03 10:00:13 +0200132 select HAVE_OPROFILE
133 select HAVE_OPTPROBES
134 select HAVE_PCSPKR_PLATFORM
135 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200136 select HAVE_PERF_EVENTS_NMI
Jiri Olsac5e63192012-08-07 15:20:36 +0200137 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200138 select HAVE_PERF_USER_STACK_DUMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200139 select HAVE_REGS_AND_STACK_ACCESS_API
140 select HAVE_SYSCALL_TRACEPOINTS
Brian Gerst0c3619e2015-06-22 07:55:20 -0400141 select HAVE_UID16 if X86_32 || IA32_EMULATION
Ingo Molnar6471b822015-06-03 10:00:13 +0200142 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300143 select HAVE_USER_RETURN_NOTIFIER
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100144 select IRQ_FORCED_THREADING
Ingo Molnar6471b822015-06-03 10:00:13 +0200145 select MODULES_USE_ELF_RELA if X86_64
146 select MODULES_USE_ELF_REL if X86_32
147 select OLD_SIGACTION if X86_32
148 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
149 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500150 select RTC_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200151 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500152 select SRCU
Ingo Molnar6471b822015-06-03 10:00:13 +0200153 select SYSCTL_EXCEPTION_TRACE
154 select USER_STACKTRACE_SUPPORT
155 select VIRT_TO_BUS
156 select X86_DEV_DMA_OPS if X86_64
157 select X86_FEATURE_NAMES if PROC_FS
Balbir Singh7d8330a2008-02-10 12:46:28 +0530158
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200159config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100160 def_bool y
161 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200162
Peter Zijlstra7fb0f1d2014-10-24 09:12:35 +0200163config PERF_EVENTS_INTEL_UNCORE
164 def_bool y
Peter Zijlstra (Intel)ce5686d2014-10-29 11:17:04 +0100165 depends on PERF_EVENTS && CPU_SUP_INTEL && PCI
Peter Zijlstra7fb0f1d2014-10-24 09:12:35 +0200166
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700167config OUTPUT_FORMAT
168 string
169 default "elf32-i386" if X86_32
170 default "elf64-x86-64" if X86_64
171
Sam Ravnborg73531902008-05-25 23:03:18 +0200172config ARCH_DEFCONFIG
Sam Ravnborgb9b39bf2008-04-29 12:48:15 +0200173 string
Sam Ravnborg73531902008-05-25 23:03:18 +0200174 default "arch/x86/configs/i386_defconfig" if X86_32
175 default "arch/x86/configs/x86_64_defconfig" if X86_64
Sam Ravnborgb9b39bf2008-04-29 12:48:15 +0200176
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100177config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100178 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100179
180config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100181 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100182
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100183config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100184 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100185
Daniel Cashman9e08f572016-01-14 15:20:06 -0800186config ARCH_MMAP_RND_BITS_MIN
187 default 28 if 64BIT
188 default 8
189
190config ARCH_MMAP_RND_BITS_MAX
191 default 32 if 64BIT
192 default 16
193
194config ARCH_MMAP_RND_COMPAT_BITS_MIN
195 default 8
196
197config ARCH_MMAP_RND_COMPAT_BITS_MAX
198 default 16
199
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100200config SBUS
201 bool
202
FUJITA Tomonori3bc4e452010-03-10 15:23:22 -0800203config NEED_DMA_MAP_STATE
Jan Beulich3120e252012-09-10 12:41:45 +0100204 def_bool y
Konrad Rzeszutek Wilka6dfa122015-04-17 15:04:48 -0400205 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
FUJITA Tomonori3bc4e452010-03-10 15:23:22 -0800206
FUJITA Tomonori18e98302010-05-26 14:44:32 -0700207config NEED_SG_DMA_LENGTH
Andrew Morton4a14d842010-05-26 14:44:33 -0700208 def_bool y
FUJITA Tomonori18e98302010-05-26 14:44:32 -0700209
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100210config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100211 def_bool y
212 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100213
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100214config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100215 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100216 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000217 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
218
219config GENERIC_BUG_RELATIVE_POINTERS
220 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100221
222config GENERIC_HWEIGHT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100223 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100224
225config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100226 def_bool y
227 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100228
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100229config RWSEM_XCHGADD_ALGORITHM
Jan Beulich3120e252012-09-10 12:41:45 +0100230 def_bool y
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100231
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100232config GENERIC_CALIBRATE_DELAY
233 def_bool y
234
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800235config ARCH_HAS_CPU_RELAX
236 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100237
Pekka Enberg1b27d052008-04-28 02:12:22 -0700238config ARCH_HAS_CACHE_LINE_SIZE
239 def_bool y
240
Mike Travisdd5af902008-01-30 13:33:32 +0100241config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900242 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100243
Tejun Heo08fc4582009-08-14 15:00:49 +0900244config NEED_PER_CPU_EMBED_FIRST_CHUNK
245 def_bool y
246
247config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900248 def_bool y
249
Johannes Berg801e4062007-12-08 02:12:39 +0100250config ARCH_HIBERNATION_POSSIBLE
251 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100252
Johannes Bergf4cb5702007-12-08 02:14:00 +0100253config ARCH_SUSPEND_POSSIBLE
254 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100255
Steve Cappercfe28c52013-04-29 14:29:48 +0100256config ARCH_WANT_HUGE_PMD_SHARE
257 def_bool y
258
Steve Capper53313b22013-04-30 08:03:42 +0100259config ARCH_WANT_GENERAL_HUGETLB
260 def_bool y
261
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100262config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000263 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100264
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100265config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000266 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100267
Ingo Molnar765c68b2008-04-09 11:03:37 +0200268config ARCH_SUPPORTS_OPTIMIZED_INLINING
269 def_bool y
270
Akinobu Mita6a11f752009-03-31 15:23:17 -0700271config ARCH_SUPPORTS_DEBUG_PAGEALLOC
272 def_bool y
273
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300274config KASAN_SHADOW_OFFSET
275 hex
276 depends on KASAN
277 default 0xdffffc0000000000
278
Shane Wang69575d32009-09-01 18:25:07 -0700279config HAVE_INTEL_TXT
280 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700281 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700282
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100283config X86_32_SMP
284 def_bool y
285 depends on X86_32 && SMP
286
287config X86_64_SMP
288 def_bool y
289 depends on X86_64 && SMP
290
Tejun Heoccbeed32009-02-09 22:17:40 +0900291config X86_32_LAZY_GS
292 def_bool y
Tejun Heo60a53172009-02-09 22:17:40 +0900293 depends on X86_32 && !CC_STACKPROTECTOR
Tejun Heoccbeed32009-02-09 22:17:40 +0900294
Borislav Petkovd61931d2010-03-05 17:34:46 +0100295config ARCH_HWEIGHT_CFLAGS
296 string
297 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
298 default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
299
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530300config ARCH_SUPPORTS_UPROBES
301 def_bool y
302
Rob Herringd20642f2014-04-18 17:19:54 -0500303config FIX_EARLYCON_MEM
304 def_bool y
305
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700306config PGTABLE_LEVELS
307 int
308 default 4 if X86_64
309 default 3 if X86_PAE
310 default 2
311
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100312source "init/Kconfig"
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700313source "kernel/Kconfig.freezer"
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100314
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100315menu "Processor type and features"
316
Randy Dunlap5ee71532012-01-16 11:57:18 -0800317config ZONE_DMA
318 bool "DMA memory allocation support" if EXPERT
319 default y
320 help
321 DMA memory allocation support allows devices with less than 32-bit
322 addressing to allocate within the first 16MB of address space.
323 Disable if no such devices will be used.
324
325 If unsure, say Y.
326
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100327config SMP
328 bool "Symmetric multi-processing support"
329 ---help---
330 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800331 a system with only one CPU, say N. If you have a system with more
332 than one CPU, say Y.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100333
Robert Graffham4a474152014-01-23 15:55:29 -0800334 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100335 machines, but will use only one CPU of a multiprocessor machine. If
336 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800337 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100338 will run faster if you say N here.
339
340 Note that if you say Y here and choose architecture "586" or
341 "Pentium" under "Processor family", the kernel will not work on 486
342 architectures. Similarly, multiprocessor kernels for the "PPro"
343 architecture may not work on all Pentium based boards.
344
345 People using multiprocessor machines who say Y here should also say
346 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
347 Management" code will be disabled if you say Y here.
348
Paul Bolle395cf962011-08-15 02:02:26 +0200349 See also <file:Documentation/x86/i386/IO-APIC.txt>,
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100350 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
351 <http://www.tldp.org/docs.html#howto>.
352
353 If you don't know what to do here, say N.
354
Josh Triplett9def39be2013-10-30 08:09:45 -0700355config X86_FEATURE_NAMES
356 bool "Processor feature human-readable names" if EMBEDDED
357 default y
358 ---help---
359 This option compiles in a table of x86 feature bits and corresponding
360 names. This is required to support /proc/cpuinfo and a few kernel
361 messages. You can disable this to save space, at the expense of
362 making those few kernel messages show numeric feature bits instead.
363
364 If in doubt, say Y.
365
Borislav Petkov6e1315f2015-12-07 10:39:42 +0100366config X86_FAST_FEATURE_TESTS
367 bool "Fast CPU feature tests" if EMBEDDED
368 default y
369 ---help---
370 Some fast-paths in the kernel depend on the capabilities of the CPU.
371 Say Y here for the kernel to patch in the appropriate code at runtime
372 based on the capabilities of the CPU. The infrastructure for patching
373 code at runtime takes up some additional space; space-constrained
374 embedded systems may wish to say N here to produce smaller, slightly
375 slower code.
376
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800377config X86_X2APIC
378 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200379 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800380 ---help---
381 This enables x2apic support on CPUs that have this feature.
382
383 This allows 32-bit apic IDs (so it can support very large systems),
384 and accesses the local apic via MSRs not via mmio.
385
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800386 If you don't know what to do here, say N.
387
Yinghai Lu6695c852008-06-19 12:13:09 -0700388config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700389 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000390 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200391 depends on X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100392 ---help---
Yinghai Lu6695c852008-06-19 12:13:09 -0700393 For old smp systems that do not have proper acpi support. Newer systems
394 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700395
Yinghai Lu26f7ef12009-01-29 14:19:22 -0800396config X86_BIGSMP
397 bool "Support for big SMP systems with more than 8 CPUs"
398 depends on X86_32 && SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100399 ---help---
Yinghai Lu26f7ef12009-01-29 14:19:22 -0800400 This option is needed for the systems that have more than 8 CPUs
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100401
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000402config GOLDFISH
403 def_bool y
404 depends on X86_GOLDFISH
405
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800406if X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800407config X86_EXTENDED_PLATFORM
408 bool "Support for extended (non-PC) x86 platforms"
409 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100410 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100411 If you disable this option then the kernel will only support
412 standard PC platforms. (which covers the vast majority of
413 systems out there.)
414
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800415 If you enable this option then you'll be able to select support
416 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100417 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800418 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800419 RDC R-321x SoC
420 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200421 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200422 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100423
424 If you have one of these systems, or if you want to build a
425 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800426endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100427
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800428if X86_64
429config X86_EXTENDED_PLATFORM
430 bool "Support for extended (non-PC) x86 platforms"
431 default y
432 ---help---
433 If you disable this option then the kernel will only support
434 standard PC platforms. (which covers the vast majority of
435 systems out there.)
436
437 If you enable this option then you'll be able to select support
438 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800439 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800440 ScaleMP vSMP
441 SGI Ultraviolet
442
443 If you have one of these systems, or if you want to build a
444 generic distribution kernel, say Y here - otherwise say N.
445endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800446# This is an alphabetically sorted list of 64 bit extended platforms
447# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800448config X86_NUMACHIP
449 bool "Numascale NumaChip"
450 depends on X86_64
451 depends on X86_EXTENDED_PLATFORM
452 depends on NUMA
453 depends on SMP
454 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700455 depends on PCI_MMCONFIG
Steffen Persvold44b111b52011-12-06 00:07:26 +0800456 ---help---
457 Adds support for Numascale NumaChip large-SMP systems. Needed to
458 enable more than ~168 cores.
459 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100460
Ingo Molnar6a485652009-01-27 18:29:13 +0100461config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800462 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100463 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100464 select PARAVIRT
465 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800466 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300467 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100468 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100469 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
470 supposed to run on these EM64T-based machines. Only choose this option
471 if you have one of these machines.
472
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800473config X86_UV
474 bool "SGI Ultraviolet"
475 depends on X86_64
476 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500477 depends on NUMA
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700478 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200479 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800480 ---help---
481 This option is needed in order to support SGI Ultraviolet systems.
482 If you don't have one of these, you should say N here.
483
484# Following is an alphabetically sorted list of 32 bit extended platforms
485# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100486
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000487config X86_GOLDFISH
488 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100489 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000490 ---help---
491 Enable support for the Goldfish virtual platform used primarily
492 for Android development. Unless you are building for the Android
493 Goldfish emulator say N here.
494
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800495config X86_INTEL_CE
496 bool "CE4100 TV platform"
497 depends on PCI
498 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800499 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800500 depends on X86_32
501 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800502 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100503 select OF
504 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800505 ---help---
506 Select for the Intel CE media processor (CE4100) SOC.
507 This option compiles in support for the CE4100 SOC for settop
508 boxes and media devices.
509
David Cohen4cb9b002013-12-16 17:37:26 -0800510config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100511 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100512 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800513 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000514 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200515 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000516 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000517 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800518 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000519 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000520 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000521 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000522 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000523 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800524 Select to build a kernel capable of supporting Intel MID (Mobile
525 Internet Device) platform systems which do not have the PCI legacy
526 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000527
David Cohen4cb9b002013-12-16 17:37:26 -0800528 Intel MID platforms are based on an Intel processor and chipset which
529 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100530
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000531config X86_INTEL_QUARK
532 bool "Intel Quark platform support"
533 depends on X86_32
534 depends on X86_EXTENDED_PLATFORM
535 depends on X86_PLATFORM_DEVICES
536 depends on X86_TSC
537 depends on PCI
538 depends on PCI_GOANY
539 depends on X86_IO_APIC
540 select IOSF_MBI
541 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200542 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000543 ---help---
544 Select to include support for Quark X1000 SoC.
545 Say Y here if you have a Quark based system such as the Arduino
546 compatible Intel Galileo.
547
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000548config X86_INTEL_LPSS
549 bool "Intel Low Power Subsystem Support"
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100550 depends on X86 && ACPI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000551 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300552 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100553 select IOSF_MBI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000554 ---help---
555 Select to build support for Intel Low Power Subsystem such as
556 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300557 things like clock tree (common clock framework) and pincontrol
558 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000559
Ken Xue92082a82015-02-06 08:27:51 +0800560config X86_AMD_PLATFORM_DEVICE
561 bool "AMD ACPI2Platform devices support"
562 depends on ACPI
563 select COMMON_CLK
564 select PINCTRL
565 ---help---
566 Select to interpret AMD specific ACPI device to platform device
567 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
568 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
569 implemented under PINCTRL subsystem.
570
David E. Boxced3ce72014-09-17 22:13:50 -0700571config IOSF_MBI
572 tristate "Intel SoC IOSF Sideband support for SoC platforms"
573 depends on PCI
574 ---help---
575 This option enables sideband register access support for Intel SoC
576 platforms. On these platforms the IOSF sideband is used in lieu of
577 MSR's for some register accesses, mostly but not limited to thermal
578 and power. Drivers may query the availability of this device to
579 determine if they need the sideband in order to work on these
580 platforms. The sideband is available on the following SoC products.
581 This list is not meant to be exclusive.
582 - BayTrail
583 - Braswell
584 - Quark
585
586 You should say Y if you are running a kernel on one of these SoC's.
587
David E. Boxed2226b2014-09-17 22:13:51 -0700588config IOSF_MBI_DEBUG
589 bool "Enable IOSF sideband access through debugfs"
590 depends on IOSF_MBI && DEBUG_FS
591 ---help---
592 Select this option to expose the IOSF sideband access registers (MCR,
593 MDR, MCRX) through debugfs to write and read register information from
594 different units on the SoC. This is most useful for obtaining device
595 state information for debug and analysis. As this is a general access
596 mechanism, users of this option would have specific knowledge of the
597 device they want to access.
598
599 If you don't require the option or are in doubt, say N.
600
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800601config X86_RDC321X
602 bool "RDC R-321x SoC"
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100603 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800604 depends on X86_EXTENDED_PLATFORM
605 select M486
606 select X86_REBOOTFIXUPS
607 ---help---
608 This option is needed for RDC R-321x system-on-chip, also known
609 as R-8610-(G).
610 If you don't have one of these chips, you should say N here.
611
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100612config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100613 bool "Support non-standard 32-bit SMP architectures"
614 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800615 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100616 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800617 This option compiles in the bigsmp and STA2X11 default
618 subarchitectures. It is intended for a generic binary
619 kernel. If you select them all, kernel will probe it one by
620 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700621
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800622# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700623
Linus Torvaldsd949f362009-09-26 09:35:07 -0700624config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100625 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700626 # MCE code calls memory_failure():
627 depends on X86_MCE
628 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700629 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
630 depends on X86_64 || !SPARSEMEM
631 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700632
Alessandro Rubini83125a32012-04-04 19:40:21 +0200633config STA2X11
634 bool "STA2X11 Companion Chip Support"
635 depends on X86_32_NON_STANDARD && PCI
636 select X86_DEV_DMA_OPS
637 select X86_DMA_REMAP
638 select SWIOTLB
639 select MFD_STA2X11
640 select ARCH_REQUIRE_GPIOLIB
641 default n
642 ---help---
643 This adds support for boards based on the STA2X11 IO-Hub,
644 a.k.a. "ConneXt". The chip is used in place of the standard
645 PC chipset, so all "standard" peripherals are missing. If this
646 option is selected the kernel will still be able to boot on
647 standard PC machines.
648
Shérab82148d12010-09-25 06:06:57 +0200649config X86_32_IRIS
650 tristate "Eurobraille/Iris poweroff module"
651 depends on X86_32
652 ---help---
653 The Iris machines from EuroBraille do not have APM or ACPI support
654 to shut themselves down properly. A special I/O sequence is
655 needed to do so, which is what this module does at
656 kernel shutdown.
657
658 This is only for Iris machines from EuroBraille.
659
660 If unused, say N.
661
Ingo Molnarae1e9132008-11-11 09:05:16 +0100662config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100663 def_bool y
664 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800665 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100666 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100667 Calculate simpler /proc/<PID>/wchan values. If this option
668 is disabled then wchan values will recurse back to the
669 caller function. This provides more accurate wchan values,
670 at the expense of slightly more scheduling overhead.
671
672 If in doubt, say "Y".
673
Borislav Petkov6276a072013-03-04 21:20:21 +0100674menuconfig HYPERVISOR_GUEST
675 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100676 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100677 Say Y here to enable options for running Linux under various hyper-
678 visors. This option enables basic hypervisor detection and platform
679 setup.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100680
Borislav Petkov6276a072013-03-04 21:20:21 +0100681 If you say N, all options in this submenu will be skipped and
682 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100683
Borislav Petkov6276a072013-03-04 21:20:21 +0100684if HYPERVISOR_GUEST
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100685
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100686config PARAVIRT
687 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100688 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100689 This changes the kernel so it can modify itself when it is run
690 under a hypervisor, potentially improving performance significantly
691 over full virtualization. However, when run without a hypervisor
692 the kernel is theoretically slower and slightly larger.
693
Borislav Petkov6276a072013-03-04 21:20:21 +0100694config PARAVIRT_DEBUG
695 bool "paravirt-ops debugging"
696 depends on PARAVIRT && DEBUG_KERNEL
697 ---help---
698 Enable to debug paravirt_ops internals. Specifically, BUG if
699 a paravirt_op is missing when it is called.
700
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700701config PARAVIRT_SPINLOCKS
702 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700703 depends on PARAVIRT && SMP
Ingo Molnar62c7a1e2015-05-11 09:47:23 +0200704 select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700705 ---help---
706 Paravirtualized spinlocks allow a pvops backend to replace the
707 spinlock implementation with something virtualization-friendly
708 (for example, block the virtual CPU rather than spinning).
709
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530710 It has a minimal impact on native kernels and gives a nice performance
711 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700712
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530713 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700714
Waiman Long45e898b2015-11-09 19:09:25 -0500715config QUEUED_LOCK_STAT
716 bool "Paravirt queued spinlock statistics"
717 depends on PARAVIRT_SPINLOCKS && DEBUG_FS && QUEUED_SPINLOCKS
718 ---help---
719 Enable the collection of statistical data on the slowpath
720 behavior of paravirtualized queued spinlocks and report
721 them on debugfs.
722
Borislav Petkov6276a072013-03-04 21:20:21 +0100723source "arch/x86/xen/Kconfig"
724
725config KVM_GUEST
726 bool "KVM Guest support (including kvmclock)"
727 depends on PARAVIRT
728 select PARAVIRT_CLOCK
729 default y
730 ---help---
731 This option enables various optimizations for running under the KVM
732 hypervisor. It includes a paravirtualized clock, so that instead
733 of relying on a PIT (or probably other) emulation by the
734 underlying device model, the host provides the guest with
735 timing infrastructure such as time of day, and system time
736
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530737config KVM_DEBUG_FS
738 bool "Enable debug information for KVM Guests in debugfs"
739 depends on KVM_GUEST && DEBUG_FS
740 default n
741 ---help---
742 This option enables collection of various statistics for KVM guest.
743 Statistics are displayed in debugfs filesystem. Enabling this option
744 may incur significant overhead.
745
Borislav Petkov6276a072013-03-04 21:20:21 +0100746source "arch/x86/lguest/Kconfig"
747
748config PARAVIRT_TIME_ACCOUNTING
749 bool "Paravirtual steal time accounting"
750 depends on PARAVIRT
751 default n
752 ---help---
753 Select this option to enable fine granularity task steal time
754 accounting. Time spent executing other tasks in parallel with
755 the current vCPU is discounted from the vCPU power. To account for
756 that, there can be a small performance impact.
757
758 If in doubt, say N here.
759
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200760config PARAVIRT_CLOCK
761 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200762
Borislav Petkov6276a072013-03-04 21:20:21 +0100763endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400764
Yinghai Lu08677212010-02-10 01:20:20 -0800765config NO_BOOTMEM
Yinghai Lu774ea0b2010-08-25 13:39:18 -0700766 def_bool y
Yinghai Lu08677212010-02-10 01:20:20 -0800767
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100768source "arch/x86/Kconfig.cpu"
769
770config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100771 def_bool X86_64
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100772 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100773 ---help---
774 Use the IA-PC HPET (High Precision Event Timer) to manage
775 time in preference to the PIT and RTC, if a HPET is
776 present.
777 HPET is the next generation timer replacing legacy 8254s.
778 The HPET provides a stable time base on SMP
779 systems, unlike the TSC, but it is more expensive to access,
780 as it is off-chip. You can find the HPET spec at
781 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100782
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100783 You can safely choose Y here. However, HPET will only be
784 activated if the platform and the BIOS support this feature.
785 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100786
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100787 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100788
789config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100790 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800791 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100792
Jacob Panbb24c472009-09-02 07:37:17 -0700793config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000794 def_bool y if X86_INTEL_MID
795 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100796 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000797 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700798 help
799 APB timer is the replacement for 8254, HPET on X86 MID platforms.
800 The APBT provides a stable time base on SMP
801 systems, unlike the TSC, but it is more expensive to access,
802 as it is off-chip. APB timers are always running regardless of CPU
803 C states, they are used as per CPU clockevent device when possible.
804
David Rientjes6a108a12011-01-20 14:44:16 -0800805# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100806# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700807config DMI
808 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800809 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800810 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100811 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700812 Enabled scanning of DMI to identify machine quirks. Say Y
813 here unless you have verified that your setup is not
814 affected by entries in the DMI blacklist. Required by PNP
815 BIOS code.
816
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100817config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700818 bool "Old AMD GART IOMMU support"
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100819 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200820 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100821 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200822 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
823 GART based hardware IOMMUs.
824
825 The GART supports full DMA access for devices with 32-bit access
826 limitations, on systems with more than 3 GB. This is usually needed
827 for USB, sound, many IDE/SATA chipsets and some other devices.
828
829 Newer systems typically have a modern AMD IOMMU, supported via
830 the CONFIG_AMD_IOMMU=y config option.
831
832 In normal configurations this driver is only active when needed:
833 there's more than 3 GB of memory and the system contains a
834 32-bit limited device.
835
836 If unsure, say Y.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100837
838config CALGARY_IOMMU
839 bool "IBM Calgary IOMMU support"
840 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700841 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100842 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100843 Support for hardware IOMMUs in IBM's xSeries x366 and x460
844 systems. Needed to run systems with more than 3GB of memory
845 properly with 32-bit PCI devices that do not support DAC
846 (Double Address Cycle). Calgary also supports bus level
847 isolation, where all DMAs pass through the IOMMU. This
848 prevents them from going anywhere except their intended
849 destination. This catches hard-to-find kernel bugs and
850 mis-behaving drivers and devices that do not use the DMA-API
851 properly to set up their DMA buffers. The IOMMU can be
852 turned off at boot time with the iommu=off parameter.
853 Normally the kernel will make the right choice by itself.
854 If unsure, say Y.
855
856config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100857 def_bool y
858 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100859 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100860 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100861 Should Calgary be enabled by default? if you choose 'y', Calgary
862 will be used (if it exists). If you choose 'n', Calgary will not be
863 used even if it exists. If you choose 'n' and would like to use
864 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
865 If unsure, say Y.
866
867# need this always selected by IOMMU for the VIA workaround
868config SWIOTLB
Joerg Roedela1afd012008-11-18 12:44:21 +0100869 def_bool y if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100870 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100871 Support for software bounce buffers used on x86-64 systems
Joe Millenbach4454d322012-09-02 17:38:20 -0700872 which don't have a hardware IOMMU. Using this PCI devices
873 which can only access 32-bits of memory can be used on systems
874 with more than 3 GB of memory.
875 If unsure, say Y.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100876
FUJITA Tomonoria8522502008-04-29 00:59:36 -0700877config IOMMU_HELPER
Jan Beulich3120e252012-09-10 12:41:45 +0100878 def_bool y
879 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
Linus Torvaldsd25e26b2008-08-25 14:15:38 -0700880
Mike Travis1184dc22008-05-12 21:21:12 +0200881config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200882 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700883 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800884 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100885 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200886 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200887 If unsure, say N.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100888
889config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800890 int "Maximum number of CPUs" if SMP && !MAXSMP
Michael K. Johnson2a3313f2009-04-21 21:44:48 -0400891 range 2 8 if SMP && X86_32 && !X86_BIGSMP
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500892 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
Josh Boyerb53b5ed2013-11-05 09:38:16 -0500893 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
Mike Travis78637a972008-12-16 17:34:00 -0800894 default "1" if !SMP
Josh Boyerb53b5ed2013-11-05 09:38:16 -0500895 default "8192" if MAXSMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800896 default "32" if SMP && X86_BIGSMP
Kirill A. Shutemovc5c19942015-05-08 13:25:45 +0300897 default "8" if SMP && X86_32
898 default "64" if SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100899 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100900 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500901 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +0300902 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100903 minimum value which makes sense is 2.
904
905 This is purely to save memory - each supported CPU adds
906 approximately eight kilobytes to the kernel image.
907
908config SCHED_SMT
909 bool "SMT (Hyperthreading) scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +0200910 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100911 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100912 SMT scheduler support improves the CPU scheduler's decision making
913 when dealing with Intel Pentium 4 chips with HyperThreading at a
914 cost of slightly increased overhead in some places. If unsure say
915 N here.
916
917config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100918 def_bool y
919 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +0200920 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100921 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100922 Multi-core scheduler support improves the CPU scheduler's decision
923 making when dealing with multi-core CPU chips at a cost of slightly
924 increased overhead in some places. If unsure say N here.
925
926source "kernel/Kconfig.preempt"
927
Thomas Gleixner30b8b002015-01-15 21:22:39 +0000928config UP_LATE_INIT
929 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +0100930 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +0000931
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100932config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +0000933 bool "Local APIC support on uniprocessors" if !PCI_MSI
934 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +0000935 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100936 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100937 A local APIC (Advanced Programmable Interrupt Controller) is an
938 integrated interrupt controller in the CPU. If you have a single-CPU
939 system which has a processor with a local APIC, you can say Y here to
940 enable and use it. If you say Y here even though your machine doesn't
941 have a local APIC, then the kernel will still run with no slowdown at
942 all. The local APIC supports CPU-generated self-interrupts (timer,
943 performance counters), and the NMI watchdog which detects hard
944 lockups.
945
946config X86_UP_IOAPIC
947 bool "IO-APIC support on uniprocessors"
948 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100949 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100950 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
951 SMP-capable replacement for PC-style interrupt controllers. Most
952 SMP systems and many recent uniprocessor systems have one.
953
954 If you have a single-CPU system with an IO-APIC, you can say Y here
955 to use it. If you say Y here even though your machine doesn't have
956 an IO-APIC, then the kernel will still run with no slowdown at all.
957
958config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100959 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +0200960 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +0800961 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +0800962 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100963
964config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +0000965 def_bool y
966 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100967
Stefan Assmann41b9eb22008-07-15 13:48:55 +0200968config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
969 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +0200970 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100971 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +0200972 This option enables a workaround that fixes a source of
973 spurious interrupts. This is recommended when threaded
974 interrupt handling is used on systems where the generation of
975 superfluous "boot interrupts" cannot be disabled.
976
977 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
978 entry in the chipset's IO-APIC is masked (as, e.g. the RT
979 kernel does during interrupt handling). On chipsets where this
980 boot IRQ generation cannot be disabled, this workaround keeps
981 the original IRQ line masked so that only the equivalent "boot
982 IRQ" is delivered to the CPUs. The workaround also tells the
983 kernel to set up the IRQ handler on the boot IRQ line. In this
984 way only one interrupt is delivered to the kernel. Otherwise
985 the spurious second interrupt may cause the kernel to bring
986 down (vital) interrupt lines.
987
988 Only affects "broken" chipsets. Interrupt sharing may be
989 increased on these systems.
990
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100991config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +0200992 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +0200993 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +0200994 default y
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100995 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +0200996 Machine Check support allows the processor to notify the
997 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100998 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +0200999 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001000
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001001config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001002 def_bool y
1003 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001004 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001005 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001006 Additional support for intel specific MCE features such as
1007 the thermal monitor.
1008
1009config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001010 def_bool y
1011 prompt "AMD MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001012 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001013 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001014 Additional support for AMD specific MCE features such as
1015 the DRAM Error Threshold.
1016
Andi Kleen4efc0672009-04-28 19:07:31 +02001017config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001018 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001019 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001020 ---help---
1021 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001022 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001023 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001024
Andi Kleenb2762682009-02-12 13:49:31 +01001025config X86_MCE_THRESHOLD
1026 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001027 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001028
Andi Kleenea149b32009-04-29 19:31:00 +02001029config X86_MCE_INJECT
Andi Kleenc1ebf832009-07-09 00:31:41 +02001030 depends on X86_MCE
Andi Kleenea149b32009-04-29 19:31:00 +02001031 tristate "Machine check injector support"
1032 ---help---
1033 Provide support for injecting machine checks for testing purposes.
1034 If you don't know what a machine check is and you don't do kernel
1035 QA it is safe to say n.
1036
Andi Kleen4efc0672009-04-28 19:07:31 +02001037config X86_THERMAL_VECTOR
1038 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001039 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001040
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001041config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001042 bool "Legacy VM86 support"
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001043 default n
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001044 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001045 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001046 This option allows user programs to put the CPU into V8086
1047 mode, which is an 80286-era approximation of 16-bit real mode.
1048
1049 Some very old versions of X and/or vbetool require this option
1050 for user mode setting. Similarly, DOSEMU will use it if
1051 available to accelerate real mode DOS programs. However, any
1052 recent version of DOSEMU, X, or vbetool should be fully
1053 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001054 fall back to software emulation. Nevertheless, if you are using
1055 a 16-bit DOS program where 16-bit performance matters, vm86
1056 mode might be faster than emulation and you might want to
1057 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001058
Ingo Molnar1e642812015-09-05 08:58:10 +02001059 Note that any app that works on a 64-bit kernel is unlikely to
1060 need this option, as 64-bit kernels don't, and can't, support
1061 V8086 mode. This option is also unrelated to 16-bit protected
1062 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001063
Ingo Molnar1e642812015-09-05 08:58:10 +02001064 Enabling this option increases the complexity of the kernel
1065 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001066
Ingo Molnar1e642812015-09-05 08:58:10 +02001067 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001068
1069config VM86
1070 bool
1071 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001072
1073config X86_16BIT
1074 bool "Enable support for 16-bit segments" if EXPERT
1075 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001076 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001077 ---help---
1078 This option is required by programs like Wine to run 16-bit
1079 protected mode legacy code on x86 processors. Disabling
1080 this option saves about 300 bytes on i386, or around 6K text
1081 plus 16K runtime memory on x86-64,
1082
1083config X86_ESPFIX32
1084 def_bool y
1085 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001086
H. Peter Anvin197725d2014-05-04 10:00:49 -07001087config X86_ESPFIX64
1088 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001089 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001090
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001091config X86_VSYSCALL_EMULATION
1092 bool "Enable vsyscall emulation" if EXPERT
1093 default y
1094 depends on X86_64
1095 ---help---
1096 This enables emulation of the legacy vsyscall page. Disabling
1097 it is roughly equivalent to booting with vsyscall=none, except
1098 that it will also disable the helpful warning if a program
1099 tries to use a vsyscall. With this option set to N, offending
1100 programs will just segfault, citing addresses of the form
1101 0xffffffffff600?00.
1102
1103 This option is required by many programs built before 2013, and
1104 care should be used even with newer programs if set to N.
1105
1106 Disabling this option saves about 7K of kernel size and
1107 possibly 4K of additional runtime pagetable memory.
1108
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001109config TOSHIBA
1110 tristate "Toshiba Laptop support"
1111 depends on X86_32
1112 ---help---
1113 This adds a driver to safely access the System Management Mode of
1114 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1115 not work on models with a Phoenix BIOS. The System Management Mode
1116 is used to set the BIOS and power saving options on Toshiba portables.
1117
1118 For information on utilities to make use of this driver see the
1119 Toshiba Linux utilities web site at:
1120 <http://www.buzzard.org.uk/toshiba/>.
1121
1122 Say Y if you intend to run this kernel on a Toshiba portable.
1123 Say N otherwise.
1124
1125config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001126 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001127 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001128 select SENSORS_DELL_SMM
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001129 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001130 This option enables legacy /proc/i8k userspace interface in hwmon
1131 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1132 temperature and allows controlling fan speeds of Dell laptops via
1133 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1134 it reports also power and hotkey status. For fan speed control is
1135 needed userspace package i8kutils.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001136
Pali Rohár039ae582015-05-14 13:16:37 +02001137 Say Y if you intend to run this kernel on old Dell laptops or want to
1138 use userspace package i8kutils.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001139 Say N otherwise.
1140
1141config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001142 bool "Enable X86 board specific fixups for reboot"
1143 depends on X86_32
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001144 ---help---
1145 This enables chipset and/or board specific fixups to be done
1146 in order to get reboot to work correctly. This is only needed on
1147 some combinations of hardware and BIOS. The symptom, for which
1148 this config is intended, is when reboot ends with a stalled/hung
1149 system.
1150
1151 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001152 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001153
1154 Say Y if you want to enable the fixup. Currently, it's safe to
1155 enable this option even if you don't need it.
1156 Say N otherwise.
1157
1158config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001159 bool "CPU microcode loading support"
1160 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001161 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Borislav Petkovfe055892015-10-20 11:54:45 +02001162 depends on BLK_DEV_INITRD
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001163 select FW_LOADER
1164 ---help---
Borislav Petkove43f6e62012-08-01 19:17:01 +02001165
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001166 If you say Y here, you will be able to update the microcode on
Peter Oruba80cc9f12008-07-28 18:44:22 +02001167 certain Intel and AMD processors. The Intel support is for the
Borislav Petkove43f6e62012-08-01 19:17:01 +02001168 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1169 Xeon etc. The AMD support is for families 0x10 and later. You will
1170 obviously need the actual microcode binary data itself which is not
1171 shipped with the Linux kernel.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001172
Peter Oruba8d86f392008-07-28 18:44:21 +02001173 This option selects the general module only, you need to select
1174 at least one vendor specific module as well.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001175
Borislav Petkove43f6e62012-08-01 19:17:01 +02001176 To compile this driver as a module, choose M here: the module
1177 will be called microcode.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001178
Peter Oruba8d86f392008-07-28 18:44:21 +02001179config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001180 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001181 depends on MICROCODE
1182 default MICROCODE
1183 select FW_LOADER
1184 ---help---
1185 This options enables microcode patch loading support for Intel
1186 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001187
Alanb8989db2014-01-20 18:01:56 +00001188 For the current Intel microcode data package go to
1189 <https://downloadcenter.intel.com> and search for
1190 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001191
Peter Oruba80cc9f12008-07-28 18:44:22 +02001192config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001193 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001194 depends on MICROCODE
1195 select FW_LOADER
1196 ---help---
1197 If you select this option, microcode patch loading support for AMD
1198 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001199
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001200config MICROCODE_OLD_INTERFACE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001201 def_bool y
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001202 depends on MICROCODE
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001203
1204config X86_MSR
1205 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001206 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001207 This device gives privileged processes access to the x86
1208 Model-Specific Registers (MSRs). It is a character device with
1209 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1210 MSR accesses are directed to a specific CPU on multi-processor
1211 systems.
1212
1213config X86_CPUID
1214 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001215 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001216 This device gives processes access to the x86 CPUID instruction to
1217 be executed on a specific processor. It is a character device
1218 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1219 /dev/cpu/31/cpuid.
1220
1221choice
1222 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001223 default HIGHMEM4G
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001224 depends on X86_32
1225
1226config NOHIGHMEM
1227 bool "off"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001228 ---help---
1229 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1230 However, the address space of 32-bit x86 processors is only 4
1231 Gigabytes large. That means that, if you have a large amount of
1232 physical memory, not all of it can be "permanently mapped" by the
1233 kernel. The physical memory that's not permanently mapped is called
1234 "high memory".
1235
1236 If you are compiling a kernel which will never run on a machine with
1237 more than 1 Gigabyte total physical RAM, answer "off" here (default
1238 choice and suitable for most users). This will result in a "3GB/1GB"
1239 split: 3GB are mapped so that each process sees a 3GB virtual memory
1240 space and the remaining part of the 4GB virtual memory space is used
1241 by the kernel to permanently map as much physical memory as
1242 possible.
1243
1244 If the machine has between 1 and 4 Gigabytes physical RAM, then
1245 answer "4GB" here.
1246
1247 If more than 4 Gigabytes is used then answer "64GB" here. This
1248 selection turns Intel PAE (Physical Address Extension) mode on.
1249 PAE implements 3-level paging on IA32 processors. PAE is fully
1250 supported by Linux, PAE mode is implemented on all recent Intel
1251 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1252 then the kernel will not boot on CPUs that don't support PAE!
1253
1254 The actual amount of total physical memory will either be
1255 auto detected or can be forced by using a kernel command line option
1256 such as "mem=256M". (Try "man bootparam" or see the documentation of
1257 your boot loader (lilo or loadlin) about how to pass options to the
1258 kernel at boot time.)
1259
1260 If unsure, say "off".
1261
1262config HIGHMEM4G
1263 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001264 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001265 Select this if you have a 32-bit processor and between 1 and 4
1266 gigabytes of physical RAM.
1267
1268config HIGHMEM64G
1269 bool "64GB"
H. Peter Anvineb068e72012-11-28 11:50:23 -08001270 depends on !M486
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001271 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001272 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001273 Select this if you have a 32-bit processor and more than 4
1274 gigabytes of physical RAM.
1275
1276endchoice
1277
1278choice
David Rientjes6a108a12011-01-20 14:44:16 -08001279 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001280 default VMSPLIT_3G
1281 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001282 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001283 Select the desired split between kernel and user memory.
1284
1285 If the address range available to the kernel is less than the
1286 physical memory installed, the remaining memory will be available
1287 as "high memory". Accessing high memory is a little more costly
1288 than low memory, as it needs to be mapped into the kernel first.
1289 Note that increasing the kernel address space limits the range
1290 available to user programs, making the address space there
1291 tighter. Selecting anything other than the default 3G/1G split
1292 will also likely make your kernel incompatible with binary-only
1293 kernel modules.
1294
1295 If you are not absolutely sure what you are doing, leave this
1296 option alone!
1297
1298 config VMSPLIT_3G
1299 bool "3G/1G user/kernel split"
1300 config VMSPLIT_3G_OPT
1301 depends on !X86_PAE
1302 bool "3G/1G user/kernel split (for full 1G low memory)"
1303 config VMSPLIT_2G
1304 bool "2G/2G user/kernel split"
1305 config VMSPLIT_2G_OPT
1306 depends on !X86_PAE
1307 bool "2G/2G user/kernel split (for full 2G low memory)"
1308 config VMSPLIT_1G
1309 bool "1G/3G user/kernel split"
1310endchoice
1311
1312config PAGE_OFFSET
1313 hex
1314 default 0xB0000000 if VMSPLIT_3G_OPT
1315 default 0x80000000 if VMSPLIT_2G
1316 default 0x78000000 if VMSPLIT_2G_OPT
1317 default 0x40000000 if VMSPLIT_1G
1318 default 0xC0000000
1319 depends on X86_32
1320
1321config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001322 def_bool y
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001323 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001324
1325config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001326 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001327 depends on X86_32 && !HIGHMEM4G
Christian Melki9d99c712015-10-05 17:31:33 +02001328 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001329 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001330 PAE is required for NX support, and furthermore enables
1331 larger swapspace support for non-overcommit purposes. It
1332 has the cost of more pagetable lookup overhead, and also
1333 consumes more pagetable space per process.
1334
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001335config ARCH_PHYS_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001336 def_bool y
1337 depends on X86_64 || X86_PAE
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001338
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001339config ARCH_DMA_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001340 def_bool y
1341 depends on X86_64 || HIGHMEM64G
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001342
Ingo Molnar10971ab2015-03-05 08:18:23 +01001343config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001344 def_bool y
1345 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001346 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001347 Certain kernel features effectively disable kernel
1348 linear 1 GB mappings (even if the CPU otherwise
1349 supports them), so don't confuse the user by printing
1350 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001351
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001352# Common NUMA Features
1353config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001354 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001355 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001356 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1357 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001358 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001359 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001360
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001361 The kernel will try to allocate memory used by a CPU on the
1362 local memory controller of the CPU and add some more
1363 NUMA awareness to the kernel.
1364
Ingo Molnarc280ea52008-11-08 13:29:45 +01001365 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001366 (or later), AMD Opteron, or EM64T NUMA.
1367
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001368 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001369 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001370
1371 Otherwise, you should say N.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001372
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001373config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001374 def_bool y
1375 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001376 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001377 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001378 Enable AMD NUMA node topology detection. You should say Y here if
1379 you have a multi processor AMD system. This uses an old method to
1380 read the NUMA configuration directly from the builtin Northbridge
1381 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1382 which also takes priority if both are compiled in.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001383
1384config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001385 def_bool y
1386 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001387 depends on X86_64 && NUMA && ACPI && PCI
1388 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001389 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001390 Enable ACPI SRAT based node topology detection.
1391
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001392# Some NUMA nodes have memory ranges that span
1393# other nodes. Even though a pfn is valid and
1394# between a node's start and end pfns, it may not
1395# reside on that node. See memmap_init_zone()
1396# for details.
1397config NODES_SPAN_OTHER_NODES
1398 def_bool y
1399 depends on X86_64_ACPI_NUMA
1400
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001401config NUMA_EMU
1402 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001403 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001404 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001405 Enable NUMA emulation. A flat machine will be split
1406 into virtual nodes when booted with "numa=fake=N", where N is the
1407 number of nodes. This is only useful for debugging.
1408
1409config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001410 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001411 range 1 10
1412 default "10" if MAXSMP
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001413 default "6" if X86_64
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001414 default "3"
1415 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001416 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001417 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001418 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001419
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001420config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001421 def_bool y
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001422 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001423
1424config NEED_NODE_MEMMAP_SIZE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001425 def_bool y
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001426 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001427
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001428config ARCH_FLATMEM_ENABLE
1429 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001430 depends on X86_32 && !NUMA
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001431
1432config ARCH_DISCONTIGMEM_ENABLE
1433 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001434 depends on NUMA && X86_32
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001435
1436config ARCH_DISCONTIGMEM_DEFAULT
1437 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001438 depends on NUMA && X86_32
1439
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001440config ARCH_SPARSEMEM_ENABLE
1441 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001442 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001443 select SPARSEMEM_STATIC if X86_32
1444 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1445
Tejun Heo3b166512011-04-01 11:15:12 +02001446config ARCH_SPARSEMEM_DEFAULT
1447 def_bool y
1448 depends on X86_64
1449
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001450config ARCH_SELECT_MEMORY_MODEL
1451 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001452 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001453
1454config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001455 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001456 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001457 help
1458 This option enables a sysfs memory/probe interface for testing.
1459 See Documentation/memory-hotplug.txt for more information.
1460 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001461
Tejun Heo3b166512011-04-01 11:15:12 +02001462config ARCH_PROC_KCORE_TEXT
1463 def_bool y
1464 depends on X86_64 && PROC_KCORE
1465
Avi Kivitya29815a2010-01-10 16:28:09 +02001466config ILLEGAL_POINTER_VALUE
1467 hex
1468 default 0 if X86_32
1469 default 0xdead000000000000 if X86_64
1470
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001471source "mm/Kconfig"
1472
Dan Williams7a678322015-08-19 00:34:34 -04001473config X86_PMEM_LEGACY_DEVICE
1474 bool
1475
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001476config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001477 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001478 depends on PHYS_ADDR_T_64BIT
1479 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001480 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001481 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001482 help
1483 Treat memory marked using the non-standard e820 type of 12 as used
1484 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1485 The kernel will offer these regions to the 'pmem' driver so
1486 they can be used for persistent storage.
1487
1488 Say Y if unsure.
1489
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001490config HIGHPTE
1491 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001492 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001493 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001494 The VM uses one page table entry for each page of physical memory.
1495 For systems with a lot of RAM, this can be wasteful of precious
1496 low memory. Setting this option will put user-space page table
1497 entries in high memory.
1498
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001499config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001500 bool "Check for low memory corruption"
1501 ---help---
1502 Periodically check for memory corruption in low memory, which
1503 is suspected to be caused by BIOS. Even when enabled in the
1504 configuration, it is disabled at runtime. Enable it by
1505 setting "memory_corruption_check=1" on the kernel command
1506 line. By default it scans the low 64k of memory every 60
1507 seconds; see the memory_corruption_check_size and
1508 memory_corruption_check_period parameters in
1509 Documentation/kernel-parameters.txt to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001510
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001511 When enabled with the default parameters, this option has
1512 almost no overhead, as it reserves a relatively small amount
1513 of memory and scans it infrequently. It both detects corruption
1514 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001515
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001516 It is, however, intended as a diagnostic tool; if repeatable
1517 BIOS-originated corruption always affects the same memory,
1518 you can use memmap= to prevent the kernel from using that
1519 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001520
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001521config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001522 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001523 depends on X86_CHECK_BIOS_CORRUPTION
1524 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001525 ---help---
1526 Set whether the default state of memory_corruption_check is
1527 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001528
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001529config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001530 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1531 default 64
1532 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001533 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001534 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001535
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001536 The first page contains BIOS data structures that the kernel
1537 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001538
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001539 By default we reserve the first 64K of physical RAM, as a
1540 number of BIOSes are known to corrupt that memory range
1541 during events such as suspend/resume or monitor cable
1542 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001543
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001544 You can set this to 4 if you are absolutely sure that you
1545 trust the BIOS to get all its memory reservations and usages
1546 right. If you know your BIOS have problems beyond the
1547 default 64K area, you can set this to 640 to avoid using the
1548 entire low memory range.
1549
1550 If you have doubts about the BIOS (e.g. suspend/resume does
1551 not work or there's kernel crashes after certain hardware
1552 hotplug events) then you might want to enable
1553 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1554 typical corruption patterns.
1555
1556 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001557
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001558config MATH_EMULATION
1559 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001560 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001561 prompt "Math emulation" if X86_32
1562 ---help---
1563 Linux can emulate a math coprocessor (used for floating point
1564 operations) if you don't have one. 486DX and Pentium processors have
1565 a math coprocessor built in, 486SX and 386 do not, unless you added
1566 a 487DX or 387, respectively. (The messages during boot time can
1567 give you some hints here ["man dmesg"].) Everyone needs either a
1568 coprocessor or this emulation.
1569
1570 If you don't have a math coprocessor, you need to say Y here; if you
1571 say Y here even though you have a coprocessor, the coprocessor will
1572 be used nevertheless. (This behavior can be changed with the kernel
1573 command line option "no387", which comes handy if your coprocessor
1574 is broken. Try "man bootparam" or see the documentation of your boot
1575 loader (lilo or loadlin) about how to pass options to the kernel at
1576 boot time.) This means that it is a good idea to say Y here if you
1577 intend to use this kernel on different machines.
1578
1579 More information about the internals of the Linux math coprocessor
1580 emulation can be found in <file:arch/x86/math-emu/README>.
1581
1582 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1583 kernel, it won't hurt.
1584
1585config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001586 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001587 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001588 ---help---
1589 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1590 the Memory Type Range Registers (MTRRs) may be used to control
1591 processor access to memory ranges. This is most useful if you have
1592 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1593 allows bus write transfers to be combined into a larger transfer
1594 before bursting over the PCI/AGP bus. This can increase performance
1595 of image write operations 2.5 times or more. Saying Y here creates a
1596 /proc/mtrr file which may be used to manipulate your processor's
1597 MTRRs. Typically the X server should use this.
1598
1599 This code has a reasonably generic interface so that similar
1600 control registers on other processors can be easily supported
1601 as well:
1602
1603 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1604 Registers (ARRs) which provide a similar functionality to MTRRs. For
1605 these, the ARRs are used to emulate the MTRRs.
1606 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1607 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1608 write-combining. All of these processors are supported by this code
1609 and it makes sense to say Y here if you have one of them.
1610
1611 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1612 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1613 can lead to all sorts of problems, so it's good to say Y here.
1614
1615 You can safely say Y even if your machine doesn't have MTRRs, you'll
1616 just add about 9 KB to your kernel.
1617
Randy Dunlap7225e752008-07-26 17:54:22 -07001618 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001619
Yinghai Lu95ffa242008-04-29 03:52:33 -07001620config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001621 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001622 prompt "MTRR cleanup support"
1623 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001624 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001625 Convert MTRR layout from continuous to discrete, so X drivers can
1626 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001627
Thomas Gleixneraba37282008-07-15 14:48:48 +02001628 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001629 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001630 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001631
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001632 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001633
1634config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001635 int "MTRR cleanup enable value (0-1)"
1636 range 0 1
1637 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001638 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001639 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001640 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001641
Yinghai Lu12031a62008-05-02 02:40:22 -07001642config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1643 int "MTRR cleanup spare reg num (0-7)"
1644 range 0 7
1645 default "1"
1646 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001647 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001648 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001649 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001650
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001651config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001652 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001653 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001654 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001655 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001656 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001657
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001658 PATs are the modern equivalents of MTRRs and are much more
1659 flexible than MTRRs.
1660
1661 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001662 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001663
1664 If unsure, say Y.
1665
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001666config ARCH_USES_PG_UNCACHED
1667 def_bool y
1668 depends on X86_PAT
1669
H. Peter Anvin628c6242011-07-31 13:59:29 -07001670config ARCH_RANDOM
1671 def_bool y
1672 prompt "x86 architectural random number generator" if EXPERT
1673 ---help---
1674 Enable the x86 architectural RDRAND instruction
1675 (Intel Bull Mountain technology) to generate random numbers.
1676 If supported, this is a high bandwidth, cryptographically
1677 secure hardware random number generator.
1678
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001679config X86_SMAP
1680 def_bool y
1681 prompt "Supervisor Mode Access Prevention" if EXPERT
1682 ---help---
1683 Supervisor Mode Access Prevention (SMAP) is a security
1684 feature in newer Intel processors. There is a small
1685 performance cost if this enabled and turned on; there is
1686 also a small increase in the kernel size if this is enabled.
1687
1688 If unsure, say Y.
1689
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001690config X86_INTEL_MPX
1691 prompt "Intel MPX (Memory Protection Extensions)"
1692 def_bool n
1693 depends on CPU_SUP_INTEL
1694 ---help---
1695 MPX provides hardware features that can be used in
1696 conjunction with compiler-instrumented code to check
1697 memory references. It is designed to detect buffer
1698 overflow or underflow bugs.
1699
1700 This option enables running applications which are
1701 instrumented or otherwise use MPX. It does not use MPX
1702 itself inside the kernel or to protect the kernel
1703 against bad memory references.
1704
1705 Enabling this option will make the kernel larger:
1706 ~8k of kernel text and 36 bytes of data on a 64-bit
1707 defconfig. It adds a long to the 'mm_struct' which
1708 will increase the kernel memory overhead of each
1709 process and adds some branches to paths used during
1710 exec() and munmap().
1711
1712 For details, see Documentation/x86/intel_mpx.txt
1713
1714 If unsure, say N.
1715
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001716config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001717 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001718 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001719 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001720 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001721 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001722 This enables the kernel to use EFI runtime services that are
1723 available (such as the EFI variable services).
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001724
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001725 This option is only useful on systems that have EFI firmware.
1726 In addition, you should use the latest ELILO loader available
1727 at <http://elilo.sourceforge.net> in order to take advantage
1728 of EFI runtime services. However, even with this option, the
1729 resultant kernel should continue to boot on existing non-EFI
1730 platforms.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001731
Matt Fleming291f3632011-12-12 21:27:52 +00001732config EFI_STUB
1733 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001734 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001735 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001736 ---help---
1737 This kernel feature allows a bzImage to be loaded directly
1738 by EFI firmware without the use of a bootloader.
1739
Roy Franz4172fe22013-09-22 15:45:25 -07001740 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001741
Matt Fleming7d453ee2014-01-10 18:52:06 +00001742config EFI_MIXED
1743 bool "EFI mixed-mode support"
1744 depends on EFI_STUB && X86_64
1745 ---help---
1746 Enabling this feature allows a 64-bit kernel to be booted
1747 on a 32-bit firmware, provided that your CPU supports 64-bit
1748 mode.
1749
1750 Note that it is not possible to boot a mixed-mode enabled
1751 kernel via the EFI boot stub - a bootloader that supports
1752 the EFI handover protocol must be used.
1753
1754 If unsure, say N.
1755
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001756config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001757 def_bool y
1758 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001759 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001760 This kernel feature is useful for number crunching applications
1761 that may need to compute untrusted bytecode during their
1762 execution. By using pipes or other transports made available to
1763 the process as file descriptors supporting the read/write
1764 syscalls, it's possible to isolate those applications in
1765 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001766 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001767 and the task is only allowed to execute a few safe syscalls
1768 defined by each seccomp mode.
1769
1770 If unsure, say Y. Only embedded should say N here.
1771
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001772source kernel/Kconfig.hz
1773
1774config KEXEC
1775 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001776 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001777 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001778 kexec is a system call that implements the ability to shutdown your
1779 current kernel, and to start another kernel. It is like a reboot
1780 but it is independent of the system firmware. And like a reboot
1781 you can start any kernel with it, not just Linux.
1782
1783 The name comes from the similarity to the exec system call.
1784
1785 It is an ongoing process to be certain the hardware in a machine
1786 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001787 initially work for you. As of this writing the exact hardware
1788 interface is strongly in flux, so no good recommendation can be
1789 made.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001790
Vivek Goyal74ca3172014-08-29 15:18:46 -07001791config KEXEC_FILE
1792 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07001793 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07001794 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07001795 depends on X86_64
1796 depends on CRYPTO=y
1797 depends on CRYPTO_SHA256=y
1798 ---help---
1799 This is new version of kexec system call. This system call is
1800 file based and takes file descriptors as system call argument
1801 for kernel and initramfs as opposed to list of segments as
1802 accepted by previous system call.
1803
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001804config KEXEC_VERIFY_SIG
1805 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07001806 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001807 ---help---
1808 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01001809 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001810
Borislav Petkovd8eb8942015-03-13 14:04:37 +01001811 In addition to that option, you need to enable signature
1812 verification for the corresponding kernel image type being
1813 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001814
1815config KEXEC_BZIMAGE_VERIFY_SIG
1816 bool "Enable bzImage signature verification support"
1817 depends on KEXEC_VERIFY_SIG
1818 depends on SIGNED_PE_FILE_VERIFICATION
1819 select SYSTEM_TRUSTED_KEYRING
1820 ---help---
1821 Enable bzImage signature verification support.
1822
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001823config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02001824 bool "kernel crash dumps"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001825 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001826 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001827 Generate crash dump after being started by kexec.
1828 This should be normally only set in special crash dump kernels
1829 which are loaded in the main kernel with kexec-tools into
1830 a specially reserved region and then later executed after
1831 a crash by kdump/kexec. The crash dump kernel must be compiled
1832 to a memory address not used by the main kernel or BIOS using
1833 PHYSICAL_START, or it must be built as a relocatable image
1834 (CONFIG_RELOCATABLE=y).
1835 For more details see Documentation/kdump/kdump.txt
1836
Huang Ying3ab83522008-07-25 19:45:07 -07001837config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07001838 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08001839 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001840 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07001841 Jump between original kernel and kexeced kernel and invoke
1842 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07001843
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001844config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08001845 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07001846 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001847 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001848 This gives the physical address where the kernel is loaded.
1849
1850 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1851 bzImage will decompress itself to above physical address and
1852 run from there. Otherwise, bzImage will run from the address where
1853 it has been loaded by the boot loader and will ignore above physical
1854 address.
1855
1856 In normal kdump cases one does not have to set/change this option
1857 as now bzImage can be compiled as a completely relocatable image
1858 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1859 address. This option is mainly useful for the folks who don't want
1860 to use a bzImage for capturing the crash dump and want to use a
1861 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1862 to be specifically compiled to run from a specific memory area
1863 (normally a reserved region) and this option comes handy.
1864
H. Peter Anvinceefccc2009-05-11 16:12:16 -07001865 So if you are using bzImage for capturing the crash dump,
1866 leave the value here unchanged to 0x1000000 and set
1867 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1868 for capturing the crash dump change this value to start of
1869 the reserved region. In other words, it can be set based on
1870 the "X" value as specified in the "crashkernel=YM@XM"
1871 command line boot parameter passed to the panic-ed
1872 kernel. Please take a look at Documentation/kdump/kdump.txt
1873 for more details about crash dumps.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001874
1875 Usage of bzImage for capturing the crash dump is recommended as
1876 one does not have to build two kernels. Same kernel can be used
1877 as production kernel and capture kernel. Above option should have
1878 gone away after relocatable bzImage support is introduced. But it
1879 is present because there are users out there who continue to use
1880 vmlinux for dump capture. This option should go away down the
1881 line.
1882
1883 Don't change this unless you know what you are doing.
1884
1885config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07001886 bool "Build a relocatable kernel"
1887 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001888 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001889 This builds a kernel image that retains relocation information
1890 so it can be loaded someplace besides the default 1MB.
1891 The relocations tend to make the kernel binary about 10% larger,
1892 but are discarded at runtime.
1893
1894 One use is for the kexec on panic case where the recovery kernel
1895 must live at a different physical address than the primary
1896 kernel.
1897
1898 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1899 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07001900 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001901
Kees Cook8ab38202013-10-10 17:18:14 -07001902config RANDOMIZE_BASE
1903 bool "Randomize the address of the kernel image"
1904 depends on RELOCATABLE
Kees Cook8ab38202013-10-10 17:18:14 -07001905 default n
1906 ---help---
1907 Randomizes the physical and virtual address at which the
1908 kernel image is decompressed, as a security feature that
1909 deters exploit attempts relying on knowledge of the location
1910 of kernel internals.
1911
Kees Cooka653f352013-11-11 14:28:39 -08001912 Entropy is generated using the RDRAND instruction if it is
1913 supported. If RDTSC is supported, it is used as well. If
1914 neither RDRAND nor RDTSC are supported, then randomness is
1915 read from the i8254 timer.
Kees Cook8ab38202013-10-10 17:18:14 -07001916
1917 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
Kees Cooka653f352013-11-11 14:28:39 -08001918 and aligned according to PHYSICAL_ALIGN. Since the kernel is
1919 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1920 minimum of 2MiB, only 10 bits of entropy is theoretically
1921 possible. At best, due to page table layouts, 64-bit can use
1922 9 bits of entropy and 32-bit uses 8 bits.
Kees Cook8ab38202013-10-10 17:18:14 -07001923
Kees Cookda2b6fb2013-12-10 12:27:45 -08001924 If unsure, say N.
1925
Kees Cook8ab38202013-10-10 17:18:14 -07001926config RANDOMIZE_BASE_MAX_OFFSET
Kees Cookda2b6fb2013-12-10 12:27:45 -08001927 hex "Maximum kASLR offset allowed" if EXPERT
Kees Cook8ab38202013-10-10 17:18:14 -07001928 depends on RANDOMIZE_BASE
Kees Cook6145cfe2013-10-10 17:18:18 -07001929 range 0x0 0x20000000 if X86_32
1930 default "0x20000000" if X86_32
1931 range 0x0 0x40000000 if X86_64
1932 default "0x40000000" if X86_64
Kees Cook8ab38202013-10-10 17:18:14 -07001933 ---help---
Kees Cookda2b6fb2013-12-10 12:27:45 -08001934 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1935 memory is used to determine the maximal offset in bytes that will
1936 be applied to the kernel when kernel Address Space Layout
1937 Randomization (kASLR) is active. This must be a multiple of
1938 PHYSICAL_ALIGN.
Kees Cook6145cfe2013-10-10 17:18:18 -07001939
Kees Cookda2b6fb2013-12-10 12:27:45 -08001940 On 32-bit this is limited to 512MiB by page table layouts. The
1941 default is 512MiB.
Kees Cook6145cfe2013-10-10 17:18:18 -07001942
Kees Cookda2b6fb2013-12-10 12:27:45 -08001943 On 64-bit this is limited by how the kernel fixmap page table is
1944 positioned, so this cannot be larger than 1GiB currently. Without
1945 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1946 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1947 modules area will shrink to compensate, up to the current maximum
1948 1GiB to 1GiB split. The default is 1GiB.
1949
1950 If unsure, leave at the default value.
Kees Cook8ab38202013-10-10 17:18:14 -07001951
1952# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07001953config X86_NEED_RELOCS
1954 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07001955 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07001956
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001957config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07001958 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07001959 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07001960 range 0x2000 0x1000000 if X86_32
1961 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001962 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001963 This value puts the alignment restrictions on physical address
1964 where kernel is loaded and run from. Kernel is compiled for an
1965 address which meets above alignment restriction.
1966
1967 If bootloader loads the kernel at a non-aligned address and
1968 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1969 address aligned to above value and run from there.
1970
1971 If bootloader loads the kernel at a non-aligned address and
1972 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1973 load address and decompress itself to the address it has been
1974 compiled for and run from there. The address for which kernel is
1975 compiled already meets above alignment restrictions. Hence the
1976 end result is that kernel runs from a physical address meeting
1977 above alignment restrictions.
1978
Kees Cooka0215062013-07-08 09:15:17 -07001979 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1980 this value must be a multiple of 0x200000.
1981
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001982 Don't change this unless you know what you are doing.
1983
1984config HOTPLUG_CPU
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05001985 bool "Support for hot-pluggable CPUs"
Stephen Rothwell40b31362013-05-21 13:49:35 +10001986 depends on SMP
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001987 ---help---
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05001988 Say Y here to allow turning CPUs off and on. CPUs can be
1989 controlled through /sys/devices/system/cpu.
1990 ( Note: power management support will enable this option
1991 automatically on SMP systems. )
1992 Say N if you want to disable CPU hotplug.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001993
Fenghua Yu80aa1df2012-11-13 11:32:39 -08001994config BOOTPARAM_HOTPLUG_CPU0
1995 bool "Set default setting of cpu0_hotpluggable"
1996 default n
Kees Cook2c922cd2013-01-22 13:01:19 -08001997 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08001998 ---help---
1999 Set whether default state of cpu0_hotpluggable is on or off.
2000
2001 Say Y here to enable CPU0 hotplug by default. If this switch
2002 is turned on, there is no need to give cpu0_hotplug kernel
2003 parameter and the CPU0 hotplug feature is enabled by default.
2004
2005 Please note: there are two known CPU0 dependencies if you want
2006 to enable the CPU0 hotplug feature either by this switch or by
2007 cpu0_hotplug kernel parameter.
2008
2009 First, resume from hibernate or suspend always starts from CPU0.
2010 So hibernate and suspend are prevented if CPU0 is offline.
2011
2012 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2013 offline if any interrupt can not migrate out of CPU0. There may
2014 be other CPU0 dependencies.
2015
2016 Please make sure the dependencies are under your control before
2017 you enable this feature.
2018
2019 Say N if you don't want to enable CPU0 hotplug feature by default.
2020 You still can enable the CPU0 hotplug feature at boot by kernel
2021 parameter cpu0_hotplug.
2022
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002023config DEBUG_HOTPLUG_CPU0
2024 def_bool n
2025 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002026 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002027 ---help---
2028 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2029 soon as possible and boots up userspace with CPU0 offlined. User
2030 can online CPU0 back after boot time.
2031
2032 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2033 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2034 compilation or giving cpu0_hotplug kernel parameter at boot.
2035
2036 If unsure, say N.
2037
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002038config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002039 def_bool n
2040 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Roland McGrathaf65d642008-01-30 13:30:43 +01002041 depends on X86_32 || IA32_EMULATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002042 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002043 Certain buggy versions of glibc will crash if they are
2044 presented with a 32-bit vDSO that is not mapped at the address
2045 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002046
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002047 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2048 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2049 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2050 the only released version with the bug, but OpenSUSE 9
2051 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002052
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002053 The symptom of the bug is that everything crashes on startup, saying:
2054 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2055
2056 Saying Y here changes the default value of the vdso32 boot
2057 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2058 This works around the glibc bug but hurts performance.
2059
2060 If unsure, say N: if you are compiling your own kernel, you
2061 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002062
Kees Cook3dc33bd2015-08-12 17:55:19 -07002063choice
2064 prompt "vsyscall table for legacy applications"
2065 depends on X86_64
2066 default LEGACY_VSYSCALL_EMULATE
2067 help
2068 Legacy user code that does not know how to find the vDSO expects
2069 to be able to issue three syscalls by calling fixed addresses in
2070 kernel space. Since this location is not randomized with ASLR,
2071 it can be used to assist security vulnerability exploitation.
2072
2073 This setting can be changed at boot time via the kernel command
2074 line parameter vsyscall=[native|emulate|none].
2075
2076 On a system with recent enough glibc (2.14 or newer) and no
2077 static binaries, you can say None without a performance penalty
2078 to improve security.
2079
2080 If unsure, select "Emulate".
2081
2082 config LEGACY_VSYSCALL_NATIVE
2083 bool "Native"
2084 help
2085 Actual executable code is located in the fixed vsyscall
2086 address mapping, implementing time() efficiently. Since
2087 this makes the mapping executable, it can be used during
2088 security vulnerability exploitation (traditionally as
2089 ROP gadgets). This configuration is not recommended.
2090
2091 config LEGACY_VSYSCALL_EMULATE
2092 bool "Emulate"
2093 help
2094 The kernel traps and emulates calls into the fixed
2095 vsyscall address mapping. This makes the mapping
2096 non-executable, but it still contains known contents,
2097 which could be used in certain rare security vulnerability
2098 exploits. This configuration is recommended when userspace
2099 still uses the vsyscall area.
2100
2101 config LEGACY_VSYSCALL_NONE
2102 bool "None"
2103 help
2104 There will be no vsyscall mapping at all. This will
2105 eliminate any risk of ASLR bypass due to the vsyscall
2106 fixed address mapping. Attempts to use the vsyscalls
2107 will be reported to dmesg, so that either old or
2108 malicious userspace programs can be identified.
2109
2110endchoice
2111
Tim Bird516cbf32008-08-12 12:52:36 -07002112config CMDLINE_BOOL
2113 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002114 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002115 Allow for specifying boot arguments to the kernel at
2116 build time. On some systems (e.g. embedded ones), it is
2117 necessary or convenient to provide some or all of the
2118 kernel boot arguments with the kernel itself (that is,
2119 to not rely on the boot loader to provide them.)
2120
2121 To compile command line arguments into the kernel,
2122 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002123 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002124
2125 Systems with fully functional boot loaders (i.e. non-embedded)
2126 should leave this option set to 'N'.
2127
2128config CMDLINE
2129 string "Built-in kernel command string"
2130 depends on CMDLINE_BOOL
2131 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002132 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002133 Enter arguments here that should be compiled into the kernel
2134 image and used at boot time. If the boot loader provides a
2135 command line at boot time, it is appended to this string to
2136 form the full kernel command line, when the system boots.
2137
2138 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2139 change this behavior.
2140
2141 In most cases, the command line (whether built-in or provided
2142 by the boot loader) should specify the device for the root
2143 file system.
2144
2145config CMDLINE_OVERRIDE
2146 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002147 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002148 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002149 Set this option to 'Y' to have the kernel ignore the boot loader
2150 command line, and use ONLY the built-in command line.
2151
2152 This is used to work around broken boot loaders. This should
2153 be set to 'N' under normal conditions.
2154
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002155config MODIFY_LDT_SYSCALL
2156 bool "Enable the LDT (local descriptor table)" if EXPERT
2157 default y
2158 ---help---
2159 Linux can allow user programs to install a per-process x86
2160 Local Descriptor Table (LDT) using the modify_ldt(2) system
2161 call. This is required to run 16-bit or segmented code such as
2162 DOSEMU or some Wine programs. It is also used by some very old
2163 threading libraries.
2164
2165 Enabling this feature adds a small amount of overhead to
2166 context switches and increases the low-level kernel attack
2167 surface. Disabling it removes the modify_ldt(2) system call.
2168
2169 Saying 'N' here may make sense for embedded or server kernels.
2170
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002171source "kernel/livepatch/Kconfig"
2172
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002173endmenu
2174
2175config ARCH_ENABLE_MEMORY_HOTPLUG
2176 def_bool y
2177 depends on X86_64 || (X86_32 && HIGHMEM)
2178
Gary Hade35551052008-10-31 10:52:03 -07002179config ARCH_ENABLE_MEMORY_HOTREMOVE
2180 def_bool y
2181 depends on MEMORY_HOTPLUG
2182
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002183config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002184 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002185 depends on NUMA
2186
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002187config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2188 def_bool y
2189 depends on X86_64 || X86_PAE
2190
Naoya Horiguchic177c812014-06-04 16:05:35 -07002191config ARCH_ENABLE_HUGEPAGE_MIGRATION
2192 def_bool y
2193 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2194
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002195menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002196
2197config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002198 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002199 depends on X86_64 && HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002200
2201source "kernel/power/Kconfig"
2202
2203source "drivers/acpi/Kconfig"
2204
Feng Tangefafc8b2009-08-14 15:23:29 -04002205source "drivers/sfi/Kconfig"
2206
Andi Kleena6b68072008-01-30 13:32:49 +01002207config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002208 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002209 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002210
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002211menuconfig APM
2212 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002213 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002214 ---help---
2215 APM is a BIOS specification for saving power using several different
2216 techniques. This is mostly useful for battery powered laptops with
2217 APM compliant BIOSes. If you say Y here, the system time will be
2218 reset after a RESUME operation, the /proc/apm device will provide
2219 battery status information, and user-space programs will receive
2220 notification of APM "events" (e.g. battery status change).
2221
2222 If you select "Y" here, you can disable actual use of the APM
2223 BIOS by passing the "apm=off" option to the kernel at boot time.
2224
2225 Note that the APM support is almost completely disabled for
2226 machines with more than one CPU.
2227
2228 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002229 and more information, read <file:Documentation/power/apm-acpi.txt>
2230 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002231 <http://www.tldp.org/docs.html#howto>.
2232
2233 This driver does not spin down disk drives (see the hdparm(8)
2234 manpage ("man 8 hdparm") for that), and it doesn't turn off
2235 VESA-compliant "green" monitors.
2236
2237 This driver does not support the TI 4000M TravelMate and the ACER
2238 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2239 desktop machines also don't have compliant BIOSes, and this driver
2240 may cause those machines to panic during the boot phase.
2241
2242 Generally, if you don't have a battery in your machine, there isn't
2243 much point in using this driver and you should say N. If you get
2244 random kernel OOPSes or reboots that don't seem to be related to
2245 anything, try disabling/enabling this option (or disabling/enabling
2246 APM in your BIOS).
2247
2248 Some other things you should try when experiencing seemingly random,
2249 "weird" problems:
2250
2251 1) make sure that you have enough swap space and that it is
2252 enabled.
2253 2) pass the "no-hlt" option to the kernel
2254 3) switch on floating point emulation in the kernel and pass
2255 the "no387" option to the kernel
2256 4) pass the "floppy=nodma" option to the kernel
2257 5) pass the "mem=4M" option to the kernel (thereby disabling
2258 all but the first 4 MB of RAM)
2259 6) make sure that the CPU is not over clocked.
2260 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2261 8) disable the cache from your BIOS settings
2262 9) install a fan for the video card or exchange video RAM
2263 10) install a better fan for the CPU
2264 11) exchange RAM chips
2265 12) exchange the motherboard.
2266
2267 To compile this driver as a module, choose M here: the
2268 module will be called apm.
2269
2270if APM
2271
2272config APM_IGNORE_USER_SUSPEND
2273 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002274 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002275 This option will ignore USER SUSPEND requests. On machines with a
2276 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2277 series notebooks, it is necessary to say Y because of a BIOS bug.
2278
2279config APM_DO_ENABLE
2280 bool "Enable PM at boot time"
2281 ---help---
2282 Enable APM features at boot time. From page 36 of the APM BIOS
2283 specification: "When disabled, the APM BIOS does not automatically
2284 power manage devices, enter the Standby State, enter the Suspend
2285 State, or take power saving steps in response to CPU Idle calls."
2286 This driver will make CPU Idle calls when Linux is idle (unless this
2287 feature is turned off -- see "Do CPU IDLE calls", below). This
2288 should always save battery power, but more complicated APM features
2289 will be dependent on your BIOS implementation. You may need to turn
2290 this option off if your computer hangs at boot time when using APM
2291 support, or if it beeps continuously instead of suspending. Turn
2292 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2293 T400CDT. This is off by default since most machines do fine without
2294 this feature.
2295
2296config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002297 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002298 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002299 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002300 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2301 On some machines, this can activate improved power savings, such as
2302 a slowed CPU clock rate, when the machine is idle. These idle calls
2303 are made after the idle loop has run for some length of time (e.g.,
2304 333 mS). On some machines, this will cause a hang at boot time or
2305 whenever the CPU becomes idle. (On machines with more than one CPU,
2306 this option does nothing.)
2307
2308config APM_DISPLAY_BLANK
2309 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002310 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002311 Enable console blanking using the APM. Some laptops can use this to
2312 turn off the LCD backlight when the screen blanker of the Linux
2313 virtual console blanks the screen. Note that this is only used by
2314 the virtual console screen blanker, and won't turn off the backlight
2315 when using the X Window system. This also doesn't have anything to
2316 do with your VESA-compliant power-saving monitor. Further, this
2317 option doesn't work for all laptops -- it might not turn off your
2318 backlight at all, or it might print a lot of errors to the console,
2319 especially if you are using gpm.
2320
2321config APM_ALLOW_INTS
2322 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002323 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002324 Normally we disable external interrupts while we are making calls to
2325 the APM BIOS as a measure to lessen the effects of a badly behaving
2326 BIOS implementation. The BIOS should reenable interrupts if it
2327 needs to. Unfortunately, some BIOSes do not -- especially those in
2328 many of the newer IBM Thinkpads. If you experience hangs when you
2329 suspend, try setting this to Y. Otherwise, say N.
2330
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002331endif # APM
2332
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002333source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002334
2335source "drivers/cpuidle/Kconfig"
2336
Andy Henroid27471fd2008-10-09 11:45:22 -07002337source "drivers/idle/Kconfig"
2338
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002339endmenu
2340
2341
2342menu "Bus options (PCI etc.)"
2343
2344config PCI
Ingo Molnar1ac97012008-05-19 14:10:14 +02002345 bool "PCI support"
Adrian Bunk1c858082008-01-30 13:32:32 +01002346 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002347 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002348 Find out whether you have a PCI motherboard. PCI is the name of a
2349 bus system, i.e. the way the CPU talks to the other stuff inside
2350 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2351 VESA. If you have PCI, say Y, otherwise N.
2352
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002353choice
2354 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002355 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002356 default PCI_GOANY
2357 ---help---
2358 On PCI systems, the BIOS can be used to detect the PCI devices and
2359 determine their configuration. However, some old PCI motherboards
2360 have BIOS bugs and may crash if this is done. Also, some embedded
2361 PCI-based systems don't have any BIOS at all. Linux can also try to
2362 detect the PCI hardware directly without using the BIOS.
2363
2364 With this option, you can specify how Linux should detect the
2365 PCI devices. If you choose "BIOS", the BIOS will be used,
2366 if you choose "Direct", the BIOS won't be used, and if you
2367 choose "MMConfig", then PCI Express MMCONFIG will be used.
2368 If you choose "Any", the kernel will try MMCONFIG, then the
2369 direct access method and falls back to the BIOS if that doesn't
2370 work. If unsure, go with the default, which is "Any".
2371
2372config PCI_GOBIOS
2373 bool "BIOS"
2374
2375config PCI_GOMMCONFIG
2376 bool "MMConfig"
2377
2378config PCI_GODIRECT
2379 bool "Direct"
2380
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002381config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002382 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002383 depends on OLPC
2384
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002385config PCI_GOANY
2386 bool "Any"
2387
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002388endchoice
2389
2390config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002391 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002392 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002393
2394# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2395config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002396 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002397 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002398
2399config PCI_MMCONFIG
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002400 def_bool y
Feng Tang5f0db7a2009-08-14 15:37:50 -04002401 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002402
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002403config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002404 def_bool y
2405 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002406
Alex Nixonb5401a92010-03-18 16:31:34 -04002407config PCI_XEN
2408 def_bool y
2409 depends on PCI && XEN
2410 select SWIOTLB_XEN
2411
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002412config PCI_DOMAINS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002413 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002414 depends on PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002415
2416config PCI_MMCONFIG
2417 bool "Support mmconfig PCI config space access"
2418 depends on X86_64 && PCI && ACPI
2419
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002420config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002421 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002422 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002423 help
2424 Read the PCI windows out of the CNB20LE host bridge. This allows
2425 PCI hotplug to work on systems with the CNB20LE chipset which do
2426 not have ACPI.
2427
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002428 There's no public spec for this chipset, and this functionality
2429 is known to be incomplete.
2430
2431 You should say N unless you know you need this.
2432
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002433source "drivers/pci/pcie/Kconfig"
2434
2435source "drivers/pci/Kconfig"
2436
David Rientjes1c00f012011-03-22 16:34:59 -07002437# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002438config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002439 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2440 default y
2441 help
2442 Enables ISA-style DMA support for devices requiring such controllers.
2443 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002444
2445if X86_32
2446
2447config ISA
2448 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002449 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002450 Find out whether you have ISA slots on your motherboard. ISA is the
2451 name of a bus system, i.e. the way the CPU talks to the other stuff
2452 inside your box. Other bus systems are PCI, EISA, MicroChannel
2453 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2454 newer boards don't support it. If you have ISA, say Y, otherwise N.
2455
2456config EISA
2457 bool "EISA support"
2458 depends on ISA
2459 ---help---
2460 The Extended Industry Standard Architecture (EISA) bus was
2461 developed as an open alternative to the IBM MicroChannel bus.
2462
2463 The EISA bus provided some of the features of the IBM MicroChannel
2464 bus while maintaining backward compatibility with cards made for
2465 the older ISA bus. The EISA bus saw limited use between 1988 and
2466 1995 when it was made obsolete by the PCI bus.
2467
2468 Say Y here if you are building a kernel for an EISA-based machine.
2469
2470 Otherwise, say N.
2471
2472source "drivers/eisa/Kconfig"
2473
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002474config SCx200
2475 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002476 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002477 This provides basic support for National Semiconductor's
2478 (now AMD's) Geode processors. The driver probes for the
2479 PCI-IDs of several on-chip devices, so its a good dependency
2480 for other scx200_* drivers.
2481
2482 If compiled as a module, the driver is named scx200.
2483
2484config SCx200HR_TIMER
2485 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002486 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002487 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002488 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002489 This driver provides a clocksource built upon the on-chip
2490 27MHz high-resolution timer. Its also a workaround for
2491 NSC Geode SC-1100's buggy TSC, which loses time when the
2492 processor goes idle (as is done by the scheduler). The
2493 other workaround is idle=poll boot option.
2494
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002495config OLPC
2496 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002497 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002498 select GPIOLIB
Thomas Gleixnerdc3119e72011-02-23 10:08:31 +01002499 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002500 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002501 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002502 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002503 Add support for detecting the unique features of the OLPC
2504 XO hardware.
2505
Daniel Drakea3128582011-06-25 17:34:10 +01002506config OLPC_XO1_PM
2507 bool "OLPC XO-1 Power Management"
Daniel Drake97c4cb72011-06-25 17:34:11 +01002508 depends on OLPC && MFD_CS5535 && PM_SLEEP
Daniel Drakea3128582011-06-25 17:34:10 +01002509 select MFD_CORE
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002510 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002511 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002512
Daniel Drakecfee9592011-06-25 17:34:17 +01002513config OLPC_XO1_RTC
2514 bool "OLPC XO-1 Real Time Clock"
2515 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2516 ---help---
2517 Add support for the XO-1 real time clock, which can be used as a
2518 programmable wakeup source.
2519
Daniel Drake7feda8e2011-06-25 17:34:12 +01002520config OLPC_XO1_SCI
2521 bool "OLPC XO-1 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002522 depends on OLPC && OLPC_XO1_PM
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002523 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002524 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002525 select GPIO_CS5535
2526 select MFD_CORE
2527 ---help---
2528 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002529 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002530 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002531 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002532 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002533 - AC adapter status updates
2534 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002535
Daniel Drakea0f30f52011-06-25 17:34:18 +01002536config OLPC_XO15_SCI
2537 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002538 depends on OLPC && ACPI
2539 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002540 ---help---
2541 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2542 - EC-driven system wakeups
2543 - AC adapter status updates
2544 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002545
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002546config ALIX
2547 bool "PCEngines ALIX System Support (LED setup)"
2548 select GPIOLIB
2549 ---help---
2550 This option enables system support for the PCEngines ALIX.
2551 At present this just sets up LEDs for GPIO control on
2552 ALIX2/3/6 boards. However, other system specific setup should
2553 get added here.
2554
2555 Note: You must still enable the drivers for GPIO and LED support
2556 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2557
2558 Note: You have to set alix.force=1 for boards with Award BIOS.
2559
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002560config NET5501
2561 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2562 select GPIOLIB
2563 ---help---
2564 This option enables system support for the Soekris Engineering net5501.
2565
Philip A. Prindeville31970592012-01-14 01:45:39 -07002566config GEOS
2567 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2568 select GPIOLIB
2569 depends on DMI
2570 ---help---
2571 This option enables system support for the Traverse Technologies GEOS.
2572
Vivien Didelot7d029122013-01-04 16:18:14 -05002573config TS5500
2574 bool "Technologic Systems TS-5500 platform support"
2575 depends on MELAN
2576 select CHECK_SIGNATURE
2577 select NEW_LEDS
2578 select LEDS_CLASS
2579 ---help---
2580 This option enables system support for the Technologic Systems TS-5500.
2581
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002582endif # X86_32
2583
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002584config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002585 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002586 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002587
2588source "drivers/pcmcia/Kconfig"
2589
2590source "drivers/pci/hotplug/Kconfig"
2591
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002592config RAPIDIO
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002593 tristate "RapidIO support"
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002594 depends on PCI
2595 default n
2596 help
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002597 If enabled this option will include drivers and the core
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002598 infrastructure code to support RapidIO interconnect devices.
2599
2600source "drivers/rapidio/Kconfig"
2601
David Herrmanne3263ab2013-08-02 14:05:22 +02002602config X86_SYSFB
2603 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2604 help
2605 Firmwares often provide initial graphics framebuffers so the BIOS,
2606 bootloader or kernel can show basic video-output during boot for
2607 user-guidance and debugging. Historically, x86 used the VESA BIOS
2608 Extensions and EFI-framebuffers for this, which are mostly limited
2609 to x86.
2610 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2611 framebuffers so the new generic system-framebuffer drivers can be
2612 used on x86. If the framebuffer is not compatible with the generic
2613 modes, it is adverticed as fallback platform framebuffer so legacy
2614 drivers like efifb, vesafb and uvesafb can pick it up.
2615 If this option is not selected, all system framebuffers are always
2616 marked as fallback platform framebuffers as usual.
2617
2618 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2619 not be able to pick up generic system framebuffers if this option
2620 is selected. You are highly encouraged to enable simplefb as
2621 replacement if you select this option. simplefb can correctly deal
2622 with generic system framebuffers. But you should still keep vesafb
2623 and others enabled as fallback if a system framebuffer is
2624 incompatible with simplefb.
2625
2626 If unsure, say Y.
2627
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002628endmenu
2629
2630
2631menu "Executable file formats / Emulations"
2632
2633source "fs/Kconfig.binfmt"
2634
2635config IA32_EMULATION
2636 bool "IA32 Emulation"
2637 depends on X86_64
Randy Dunlapd1603992013-06-18 12:33:40 -07002638 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002639 select COMPAT_BINFMT_ELF
Brian Gerst3bead552015-06-22 07:55:19 -04002640 select ARCH_WANT_OLD_COMPAT_IPC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002641 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002642 Include code to run legacy 32-bit programs under a
2643 64-bit kernel. You should likely turn this on, unless you're
2644 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002645
2646config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002647 tristate "IA32 a.out support"
2648 depends on IA32_EMULATION
2649 ---help---
2650 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002651
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002652config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002653 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002654 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002655 ---help---
2656 Include code to run binaries for the x32 native 32-bit ABI
2657 for 64-bit processors. An x32 process gets access to the
2658 full 64-bit register file and wide data path while leaving
2659 pointers at 32 bits for smaller memory footprint.
2660
2661 You will need a recent binutils (2.22 or later) with
2662 elf32_x86_64 support enabled to compile a kernel with this
2663 option set.
2664
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002665config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002666 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002667 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002668
Jan Beulich3120e252012-09-10 12:41:45 +01002669if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002670config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002671 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002672
2673config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002674 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002675 depends on SYSVIPC
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002676
David Howellsee009e4a02011-03-07 15:06:20 +00002677config KEYS_COMPAT
Jan Beulich3120e252012-09-10 12:41:45 +01002678 def_bool y
2679 depends on KEYS
2680endif
David Howellsee009e4a02011-03-07 15:06:20 +00002681
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002682endmenu
2683
2684
Keith Packarde5beae12008-11-03 18:21:45 +01002685config HAVE_ATOMIC_IOMAP
2686 def_bool y
2687 depends on X86_32
2688
Alessandro Rubini4692d772012-04-04 19:39:58 +02002689config X86_DEV_DMA_OPS
2690 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002691 depends on X86_64 || STA2X11
Alessandro Rubini4692d772012-04-04 19:39:58 +02002692
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002693config X86_DMA_REMAP
2694 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002695 depends on STA2X11
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002696
Li, Aubrey93e5ead2014-06-30 14:08:42 +08002697config PMC_ATOM
2698 def_bool y
2699 depends on PCI
2700
Keith Busch185a3832016-01-12 13:18:10 -07002701config VMD
2702 depends on PCI_MSI
2703 tristate "Volume Management Device Driver"
2704 default N
2705 ---help---
2706 Adds support for the Intel Volume Management Device (VMD). VMD is a
2707 secondary PCI host bridge that allows PCI Express root ports,
2708 and devices attached to them, to be removed from the default
2709 PCI domain and placed within the VMD domain. This provides
2710 more bus resources than are otherwise possible with a
2711 single domain. If you know your system provides one of these and
2712 has devices attached to it, say Y; if you are not sure, say N.
2713
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002714source "net/Kconfig"
2715
2716source "drivers/Kconfig"
2717
2718source "drivers/firmware/Kconfig"
2719
2720source "fs/Kconfig"
2721
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002722source "arch/x86/Kconfig.debug"
2723
2724source "security/Kconfig"
2725
2726source "crypto/Kconfig"
2727
Avi Kivityedf88412007-12-16 11:02:48 +02002728source "arch/x86/kvm/Kconfig"
2729
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002730source "lib/Kconfig"