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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
Ingo Molnar6471b822015-06-03 10:00:13 +020027 select ARCH_HAS_ELF_RANDOMIZE
Linus Torvalds72d93102014-09-13 11:14:53 -070028 select ARCH_HAS_FAST_MULTIPLIER
Riku Voipio957e3fa2014-12-12 16:57:44 -080029 select ARCH_HAS_GCOV_PROFILE_ALL
Dan Williams96601ad2015-08-24 18:29:38 -040030 select ARCH_HAS_PMEM_API if X86_64
Ross Zwisler67a3e8f2015-08-27 13:14:20 -060031 select ARCH_HAS_MMIO_FLUSH
Ingo Molnar6471b822015-06-03 10:00:13 +020032 select ARCH_HAS_SG_CHAIN
33 select ARCH_HAVE_NMI_SAFE_CMPXCHG
34 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040035 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080036 select ARCH_MIGHT_HAVE_PC_SERIO
Ingo Molnar6471b822015-06-03 10:00:13 +020037 select ARCH_SUPPORTS_ATOMIC_RMW
Mel Gorman3b242c62015-06-30 14:57:13 -070038 select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
Ingo Molnar6471b822015-06-03 10:00:13 +020039 select ARCH_SUPPORTS_INT128 if X86_64
40 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
41 select ARCH_USE_BUILTIN_BSWAP
42 select ARCH_USE_CMPXCHG_LOCKREF if X86_64
43 select ARCH_USE_QUEUED_RWLOCKS
44 select ARCH_USE_QUEUED_SPINLOCKS
Mel Gorman72b252a2015-09-04 15:47:32 -070045 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP
Ingo Molnar5aaeb5c2015-07-17 12:28:12 +020046 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Ingo Molnarda4276b2009-01-07 11:05:10 +010047 select ARCH_WANT_FRAME_POINTERS
Ingo Molnar6471b822015-06-03 10:00:13 +020048 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
49 select ARCH_WANT_OPTIONAL_GPIOLIB
50 select BUILDTIME_EXTABLE_SORT
51 select CLKEVT_I8253
52 select CLKSRC_I8253 if X86_32
53 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
54 select CLOCKSOURCE_WATCHDOG
55 select CLONE_BACKWARDS if X86_32
56 select COMPAT_OLD_SIGACTION if IA32_EMULATION
57 select DCACHE_WORD_ACCESS
Linus Torvalds45471cd2015-06-24 19:52:06 -070058 select EDAC_ATOMIC_SCRUB
59 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +020060 select GENERIC_CLOCKEVENTS
61 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
62 select GENERIC_CLOCKEVENTS_MIN_ADJUST
63 select GENERIC_CMOS_UPDATE
64 select GENERIC_CPU_AUTOPROBE
65 select GENERIC_EARLY_IOREMAP
66 select GENERIC_FIND_FIRST_BIT
67 select GENERIC_IOMAP
68 select GENERIC_IRQ_PROBE
69 select GENERIC_IRQ_SHOW
70 select GENERIC_PENDING_IRQ if SMP
71 select GENERIC_SMP_IDLE_THREAD
72 select GENERIC_STRNCPY_FROM_USER
73 select GENERIC_STRNLEN_USER
74 select GENERIC_TIME_VSYSCALL
75 select HAVE_ACPI_APEI if ACPI
76 select HAVE_ACPI_APEI_NMI if ACPI
77 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
78 select HAVE_AOUT if X86_32
79 select HAVE_ARCH_AUDITSYSCALL
80 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
81 select HAVE_ARCH_JUMP_LABEL
82 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
83 select HAVE_ARCH_KGDB
84 select HAVE_ARCH_KMEMCHECK
85 select HAVE_ARCH_SECCOMP_FILTER
86 select HAVE_ARCH_SOFT_DIRTY if X86_64
87 select HAVE_ARCH_TRACEHOOK
88 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
89 select HAVE_BPF_JIT if X86_64
90 select HAVE_CC_STACKPROTECTOR
91 select HAVE_CMPXCHG_DOUBLE
92 select HAVE_CMPXCHG_LOCAL
93 select HAVE_CONTEXT_TRACKING if X86_64
Josh Triplettc1bd55f2015-06-30 15:00:00 -070094 select HAVE_COPY_THREAD_TLS
Ingo Molnar6471b822015-06-03 10:00:13 +020095 select HAVE_C_RECORDMCOUNT
96 select HAVE_DEBUG_KMEMLEAK
97 select HAVE_DEBUG_STACKOVERFLOW
98 select HAVE_DMA_API_DEBUG
FUJITA Tomonori7c095e42009-06-17 16:28:12 -070099 select HAVE_DMA_ATTRS
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700100 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400101 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900102 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Johannes Berg58340a02008-07-25 01:45:33 -0700103 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Ingo Molnar6471b822015-06-03 10:00:13 +0200104 select HAVE_FENTRY if X86_64
105 select HAVE_FTRACE_MCOUNT_RECORD
106 select HAVE_FUNCTION_GRAPH_FP_TEST
107 select HAVE_FUNCTION_GRAPH_TRACER
108 select HAVE_FUNCTION_TRACER
109 select HAVE_GENERIC_DMA_COHERENT if X86_32
K.Prasad0067f122009-06-01 23:43:57 +0530110 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200111 select HAVE_IDE
112 select HAVE_IOREMAP_PROT
113 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
114 select HAVE_IRQ_TIME_ACCOUNTING
115 select HAVE_KERNEL_BZIP2
116 select HAVE_KERNEL_GZIP
117 select HAVE_KERNEL_LZ4
118 select HAVE_KERNEL_LZMA
119 select HAVE_KERNEL_LZO
120 select HAVE_KERNEL_XZ
121 select HAVE_KPROBES
122 select HAVE_KPROBES_ON_FTRACE
123 select HAVE_KRETPROBES
124 select HAVE_KVM
125 select HAVE_LIVEPATCH if X86_64
126 select HAVE_MEMBLOCK
127 select HAVE_MEMBLOCK_NODE_MAP
Frederic Weisbecker01027522010-04-11 18:55:56 +0200128 select HAVE_MIXED_BREAKPOINTS_REGS
Ingo Molnar6471b822015-06-03 10:00:13 +0200129 select HAVE_OPROFILE
130 select HAVE_OPTPROBES
131 select HAVE_PCSPKR_PLATFORM
132 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200133 select HAVE_PERF_EVENTS_NMI
Jiri Olsac5e63192012-08-07 15:20:36 +0200134 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200135 select HAVE_PERF_USER_STACK_DUMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200136 select HAVE_REGS_AND_STACK_ACCESS_API
137 select HAVE_SYSCALL_TRACEPOINTS
Brian Gerst0c3619e2015-06-22 07:55:20 -0400138 select HAVE_UID16 if X86_32 || IA32_EMULATION
Ingo Molnar6471b822015-06-03 10:00:13 +0200139 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300140 select HAVE_USER_RETURN_NOTIFIER
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100141 select IRQ_FORCED_THREADING
Ingo Molnar6471b822015-06-03 10:00:13 +0200142 select MODULES_USE_ELF_RELA if X86_64
143 select MODULES_USE_ELF_REL if X86_32
144 select OLD_SIGACTION if X86_32
145 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
146 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500147 select RTC_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200148 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500149 select SRCU
Ingo Molnar6471b822015-06-03 10:00:13 +0200150 select SYSCTL_EXCEPTION_TRACE
151 select USER_STACKTRACE_SUPPORT
152 select VIRT_TO_BUS
153 select X86_DEV_DMA_OPS if X86_64
154 select X86_FEATURE_NAMES if PROC_FS
Balbir Singh7d8330a2008-02-10 12:46:28 +0530155
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200156config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100157 def_bool y
158 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200159
Peter Zijlstra7fb0f1d2014-10-24 09:12:35 +0200160config PERF_EVENTS_INTEL_UNCORE
161 def_bool y
Peter Zijlstra (Intel)ce5686d2014-10-29 11:17:04 +0100162 depends on PERF_EVENTS && CPU_SUP_INTEL && PCI
Peter Zijlstra7fb0f1d2014-10-24 09:12:35 +0200163
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700164config OUTPUT_FORMAT
165 string
166 default "elf32-i386" if X86_32
167 default "elf64-x86-64" if X86_64
168
Sam Ravnborg73531902008-05-25 23:03:18 +0200169config ARCH_DEFCONFIG
Sam Ravnborgb9b39bf2008-04-29 12:48:15 +0200170 string
Sam Ravnborg73531902008-05-25 23:03:18 +0200171 default "arch/x86/configs/i386_defconfig" if X86_32
172 default "arch/x86/configs/x86_64_defconfig" if X86_64
Sam Ravnborgb9b39bf2008-04-29 12:48:15 +0200173
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100174config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100175 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100176
177config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100178 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100179
Heiko Carstensaa7d9352008-02-01 17:45:14 +0100180config HAVE_LATENCYTOP_SUPPORT
181 def_bool y
182
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
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100186config SBUS
187 bool
188
FUJITA Tomonori3bc4e452010-03-10 15:23:22 -0800189config NEED_DMA_MAP_STATE
Jan Beulich3120e252012-09-10 12:41:45 +0100190 def_bool y
Konrad Rzeszutek Wilka6dfa122015-04-17 15:04:48 -0400191 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
FUJITA Tomonori3bc4e452010-03-10 15:23:22 -0800192
FUJITA Tomonori18e98302010-05-26 14:44:32 -0700193config NEED_SG_DMA_LENGTH
Andrew Morton4a14d842010-05-26 14:44:33 -0700194 def_bool y
FUJITA Tomonori18e98302010-05-26 14:44:32 -0700195
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100196config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100197 def_bool y
198 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100199
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100200config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100201 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100202 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000203 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
204
205config GENERIC_BUG_RELATIVE_POINTERS
206 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100207
208config GENERIC_HWEIGHT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100209 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100210
211config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100212 def_bool y
213 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100214
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100215config RWSEM_XCHGADD_ALGORITHM
Jan Beulich3120e252012-09-10 12:41:45 +0100216 def_bool y
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100217
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100218config GENERIC_CALIBRATE_DELAY
219 def_bool y
220
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800221config ARCH_HAS_CPU_RELAX
222 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100223
Pekka Enberg1b27d052008-04-28 02:12:22 -0700224config ARCH_HAS_CACHE_LINE_SIZE
225 def_bool y
226
Mike Travisdd5af902008-01-30 13:33:32 +0100227config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900228 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100229
Tejun Heo08fc4582009-08-14 15:00:49 +0900230config NEED_PER_CPU_EMBED_FIRST_CHUNK
231 def_bool y
232
233config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900234 def_bool y
235
Johannes Berg801e4062007-12-08 02:12:39 +0100236config ARCH_HIBERNATION_POSSIBLE
237 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100238
Johannes Bergf4cb5702007-12-08 02:14:00 +0100239config ARCH_SUSPEND_POSSIBLE
240 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100241
Steve Cappercfe28c52013-04-29 14:29:48 +0100242config ARCH_WANT_HUGE_PMD_SHARE
243 def_bool y
244
Steve Capper53313b22013-04-30 08:03:42 +0100245config ARCH_WANT_GENERAL_HUGETLB
246 def_bool y
247
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100248config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000249 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100250
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100251config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000252 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100253
Ingo Molnar765c68b2008-04-09 11:03:37 +0200254config ARCH_SUPPORTS_OPTIMIZED_INLINING
255 def_bool y
256
Akinobu Mita6a11f752009-03-31 15:23:17 -0700257config ARCH_SUPPORTS_DEBUG_PAGEALLOC
258 def_bool y
259
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300260config KASAN_SHADOW_OFFSET
261 hex
262 depends on KASAN
263 default 0xdffffc0000000000
264
Shane Wang69575d32009-09-01 18:25:07 -0700265config HAVE_INTEL_TXT
266 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700267 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700268
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100269config X86_32_SMP
270 def_bool y
271 depends on X86_32 && SMP
272
273config X86_64_SMP
274 def_bool y
275 depends on X86_64 && SMP
276
Tejun Heoccbeed32009-02-09 22:17:40 +0900277config X86_32_LAZY_GS
278 def_bool y
Tejun Heo60a53172009-02-09 22:17:40 +0900279 depends on X86_32 && !CC_STACKPROTECTOR
Tejun Heoccbeed32009-02-09 22:17:40 +0900280
Borislav Petkovd61931d2010-03-05 17:34:46 +0100281config ARCH_HWEIGHT_CFLAGS
282 string
283 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
284 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
285
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530286config ARCH_SUPPORTS_UPROBES
287 def_bool y
288
Rob Herringd20642f2014-04-18 17:19:54 -0500289config FIX_EARLYCON_MEM
290 def_bool y
291
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700292config PGTABLE_LEVELS
293 int
294 default 4 if X86_64
295 default 3 if X86_PAE
296 default 2
297
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100298source "init/Kconfig"
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700299source "kernel/Kconfig.freezer"
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100300
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100301menu "Processor type and features"
302
Randy Dunlap5ee71532012-01-16 11:57:18 -0800303config ZONE_DMA
304 bool "DMA memory allocation support" if EXPERT
305 default y
306 help
307 DMA memory allocation support allows devices with less than 32-bit
308 addressing to allocate within the first 16MB of address space.
309 Disable if no such devices will be used.
310
311 If unsure, say Y.
312
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100313config SMP
314 bool "Symmetric multi-processing support"
315 ---help---
316 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800317 a system with only one CPU, say N. If you have a system with more
318 than one CPU, say Y.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100319
Robert Graffham4a474152014-01-23 15:55:29 -0800320 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100321 machines, but will use only one CPU of a multiprocessor machine. If
322 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800323 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100324 will run faster if you say N here.
325
326 Note that if you say Y here and choose architecture "586" or
327 "Pentium" under "Processor family", the kernel will not work on 486
328 architectures. Similarly, multiprocessor kernels for the "PPro"
329 architecture may not work on all Pentium based boards.
330
331 People using multiprocessor machines who say Y here should also say
332 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
333 Management" code will be disabled if you say Y here.
334
Paul Bolle395cf962011-08-15 02:02:26 +0200335 See also <file:Documentation/x86/i386/IO-APIC.txt>,
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100336 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
337 <http://www.tldp.org/docs.html#howto>.
338
339 If you don't know what to do here, say N.
340
Josh Triplett9def39be2013-10-30 08:09:45 -0700341config X86_FEATURE_NAMES
342 bool "Processor feature human-readable names" if EMBEDDED
343 default y
344 ---help---
345 This option compiles in a table of x86 feature bits and corresponding
346 names. This is required to support /proc/cpuinfo and a few kernel
347 messages. You can disable this to save space, at the expense of
348 making those few kernel messages show numeric feature bits instead.
349
350 If in doubt, say Y.
351
Borislav Petkov6e1315f2015-12-07 10:39:42 +0100352config X86_FAST_FEATURE_TESTS
353 bool "Fast CPU feature tests" if EMBEDDED
354 default y
355 ---help---
356 Some fast-paths in the kernel depend on the capabilities of the CPU.
357 Say Y here for the kernel to patch in the appropriate code at runtime
358 based on the capabilities of the CPU. The infrastructure for patching
359 code at runtime takes up some additional space; space-constrained
360 embedded systems may wish to say N here to produce smaller, slightly
361 slower code.
362
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800363config X86_X2APIC
364 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200365 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800366 ---help---
367 This enables x2apic support on CPUs that have this feature.
368
369 This allows 32-bit apic IDs (so it can support very large systems),
370 and accesses the local apic via MSRs not via mmio.
371
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800372 If you don't know what to do here, say N.
373
Yinghai Lu6695c852008-06-19 12:13:09 -0700374config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700375 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000376 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200377 depends on X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100378 ---help---
Yinghai Lu6695c852008-06-19 12:13:09 -0700379 For old smp systems that do not have proper acpi support. Newer systems
380 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700381
Yinghai Lu26f7ef12009-01-29 14:19:22 -0800382config X86_BIGSMP
383 bool "Support for big SMP systems with more than 8 CPUs"
384 depends on X86_32 && SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100385 ---help---
Yinghai Lu26f7ef12009-01-29 14:19:22 -0800386 This option is needed for the systems that have more than 8 CPUs
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100387
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000388config GOLDFISH
389 def_bool y
390 depends on X86_GOLDFISH
391
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800392if X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800393config X86_EXTENDED_PLATFORM
394 bool "Support for extended (non-PC) x86 platforms"
395 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100396 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100397 If you disable this option then the kernel will only support
398 standard PC platforms. (which covers the vast majority of
399 systems out there.)
400
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800401 If you enable this option then you'll be able to select support
402 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100403 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800404 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800405 RDC R-321x SoC
406 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200407 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200408 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100409
410 If you have one of these systems, or if you want to build a
411 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800412endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100413
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800414if X86_64
415config X86_EXTENDED_PLATFORM
416 bool "Support for extended (non-PC) x86 platforms"
417 default y
418 ---help---
419 If you disable this option then the kernel will only support
420 standard PC platforms. (which covers the vast majority of
421 systems out there.)
422
423 If you enable this option then you'll be able to select support
424 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800425 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800426 ScaleMP vSMP
427 SGI Ultraviolet
428
429 If you have one of these systems, or if you want to build a
430 generic distribution kernel, say Y here - otherwise say N.
431endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800432# This is an alphabetically sorted list of 64 bit extended platforms
433# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800434config X86_NUMACHIP
435 bool "Numascale NumaChip"
436 depends on X86_64
437 depends on X86_EXTENDED_PLATFORM
438 depends on NUMA
439 depends on SMP
440 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700441 depends on PCI_MMCONFIG
Steffen Persvold44b111b52011-12-06 00:07:26 +0800442 ---help---
443 Adds support for Numascale NumaChip large-SMP systems. Needed to
444 enable more than ~168 cores.
445 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100446
Ingo Molnar6a485652009-01-27 18:29:13 +0100447config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800448 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100449 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100450 select PARAVIRT
451 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800452 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300453 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100454 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100455 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
456 supposed to run on these EM64T-based machines. Only choose this option
457 if you have one of these machines.
458
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800459config X86_UV
460 bool "SGI Ultraviolet"
461 depends on X86_64
462 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500463 depends on NUMA
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700464 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200465 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800466 ---help---
467 This option is needed in order to support SGI Ultraviolet systems.
468 If you don't have one of these, you should say N here.
469
470# Following is an alphabetically sorted list of 32 bit extended platforms
471# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100472
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000473config X86_GOLDFISH
474 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100475 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000476 ---help---
477 Enable support for the Goldfish virtual platform used primarily
478 for Android development. Unless you are building for the Android
479 Goldfish emulator say N here.
480
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800481config X86_INTEL_CE
482 bool "CE4100 TV platform"
483 depends on PCI
484 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800485 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800486 depends on X86_32
487 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800488 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100489 select OF
490 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800491 ---help---
492 Select for the Intel CE media processor (CE4100) SOC.
493 This option compiles in support for the CE4100 SOC for settop
494 boxes and media devices.
495
David Cohen4cb9b002013-12-16 17:37:26 -0800496config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100497 bool "Intel MID platform support"
498 depends on X86_32
499 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800500 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000501 depends on PCI
502 depends on PCI_GOANY
503 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000504 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800505 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000506 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000507 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000508 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000509 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000510 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800511 Select to build a kernel capable of supporting Intel MID (Mobile
512 Internet Device) platform systems which do not have the PCI legacy
513 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000514
David Cohen4cb9b002013-12-16 17:37:26 -0800515 Intel MID platforms are based on an Intel processor and chipset which
516 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100517
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000518config X86_INTEL_QUARK
519 bool "Intel Quark platform support"
520 depends on X86_32
521 depends on X86_EXTENDED_PLATFORM
522 depends on X86_PLATFORM_DEVICES
523 depends on X86_TSC
524 depends on PCI
525 depends on PCI_GOANY
526 depends on X86_IO_APIC
527 select IOSF_MBI
528 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200529 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000530 ---help---
531 Select to include support for Quark X1000 SoC.
532 Say Y here if you have a Quark based system such as the Arduino
533 compatible Intel Galileo.
534
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000535config X86_INTEL_LPSS
536 bool "Intel Low Power Subsystem Support"
537 depends on ACPI
538 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300539 select PINCTRL
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000540 ---help---
541 Select to build support for Intel Low Power Subsystem such as
542 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300543 things like clock tree (common clock framework) and pincontrol
544 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000545
Ken Xue92082a82015-02-06 08:27:51 +0800546config X86_AMD_PLATFORM_DEVICE
547 bool "AMD ACPI2Platform devices support"
548 depends on ACPI
549 select COMMON_CLK
550 select PINCTRL
551 ---help---
552 Select to interpret AMD specific ACPI device to platform device
553 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
554 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
555 implemented under PINCTRL subsystem.
556
David E. Boxced3ce72014-09-17 22:13:50 -0700557config IOSF_MBI
558 tristate "Intel SoC IOSF Sideband support for SoC platforms"
559 depends on PCI
560 ---help---
561 This option enables sideband register access support for Intel SoC
562 platforms. On these platforms the IOSF sideband is used in lieu of
563 MSR's for some register accesses, mostly but not limited to thermal
564 and power. Drivers may query the availability of this device to
565 determine if they need the sideband in order to work on these
566 platforms. The sideband is available on the following SoC products.
567 This list is not meant to be exclusive.
568 - BayTrail
569 - Braswell
570 - Quark
571
572 You should say Y if you are running a kernel on one of these SoC's.
573
David E. Boxed2226b2014-09-17 22:13:51 -0700574config IOSF_MBI_DEBUG
575 bool "Enable IOSF sideband access through debugfs"
576 depends on IOSF_MBI && DEBUG_FS
577 ---help---
578 Select this option to expose the IOSF sideband access registers (MCR,
579 MDR, MCRX) through debugfs to write and read register information from
580 different units on the SoC. This is most useful for obtaining device
581 state information for debug and analysis. As this is a general access
582 mechanism, users of this option would have specific knowledge of the
583 device they want to access.
584
585 If you don't require the option or are in doubt, say N.
586
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800587config X86_RDC321X
588 bool "RDC R-321x SoC"
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100589 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800590 depends on X86_EXTENDED_PLATFORM
591 select M486
592 select X86_REBOOTFIXUPS
593 ---help---
594 This option is needed for RDC R-321x system-on-chip, also known
595 as R-8610-(G).
596 If you don't have one of these chips, you should say N here.
597
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100598config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100599 bool "Support non-standard 32-bit SMP architectures"
600 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800601 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100602 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800603 This option compiles in the bigsmp and STA2X11 default
604 subarchitectures. It is intended for a generic binary
605 kernel. If you select them all, kernel will probe it one by
606 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700607
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800608# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700609
Linus Torvaldsd949f362009-09-26 09:35:07 -0700610config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100611 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700612 # MCE code calls memory_failure():
613 depends on X86_MCE
614 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700615 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
616 depends on X86_64 || !SPARSEMEM
617 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700618
Alessandro Rubini83125a32012-04-04 19:40:21 +0200619config STA2X11
620 bool "STA2X11 Companion Chip Support"
621 depends on X86_32_NON_STANDARD && PCI
622 select X86_DEV_DMA_OPS
623 select X86_DMA_REMAP
624 select SWIOTLB
625 select MFD_STA2X11
626 select ARCH_REQUIRE_GPIOLIB
627 default n
628 ---help---
629 This adds support for boards based on the STA2X11 IO-Hub,
630 a.k.a. "ConneXt". The chip is used in place of the standard
631 PC chipset, so all "standard" peripherals are missing. If this
632 option is selected the kernel will still be able to boot on
633 standard PC machines.
634
Shérab82148d12010-09-25 06:06:57 +0200635config X86_32_IRIS
636 tristate "Eurobraille/Iris poweroff module"
637 depends on X86_32
638 ---help---
639 The Iris machines from EuroBraille do not have APM or ACPI support
640 to shut themselves down properly. A special I/O sequence is
641 needed to do so, which is what this module does at
642 kernel shutdown.
643
644 This is only for Iris machines from EuroBraille.
645
646 If unused, say N.
647
Ingo Molnarae1e9132008-11-11 09:05:16 +0100648config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100649 def_bool y
650 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800651 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100652 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100653 Calculate simpler /proc/<PID>/wchan values. If this option
654 is disabled then wchan values will recurse back to the
655 caller function. This provides more accurate wchan values,
656 at the expense of slightly more scheduling overhead.
657
658 If in doubt, say "Y".
659
Borislav Petkov6276a072013-03-04 21:20:21 +0100660menuconfig HYPERVISOR_GUEST
661 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100662 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100663 Say Y here to enable options for running Linux under various hyper-
664 visors. This option enables basic hypervisor detection and platform
665 setup.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100666
Borislav Petkov6276a072013-03-04 21:20:21 +0100667 If you say N, all options in this submenu will be skipped and
668 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100669
Borislav Petkov6276a072013-03-04 21:20:21 +0100670if HYPERVISOR_GUEST
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100671
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100672config PARAVIRT
673 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100674 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100675 This changes the kernel so it can modify itself when it is run
676 under a hypervisor, potentially improving performance significantly
677 over full virtualization. However, when run without a hypervisor
678 the kernel is theoretically slower and slightly larger.
679
Borislav Petkov6276a072013-03-04 21:20:21 +0100680config PARAVIRT_DEBUG
681 bool "paravirt-ops debugging"
682 depends on PARAVIRT && DEBUG_KERNEL
683 ---help---
684 Enable to debug paravirt_ops internals. Specifically, BUG if
685 a paravirt_op is missing when it is called.
686
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700687config PARAVIRT_SPINLOCKS
688 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700689 depends on PARAVIRT && SMP
Ingo Molnar62c7a1e2015-05-11 09:47:23 +0200690 select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700691 ---help---
692 Paravirtualized spinlocks allow a pvops backend to replace the
693 spinlock implementation with something virtualization-friendly
694 (for example, block the virtual CPU rather than spinning).
695
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530696 It has a minimal impact on native kernels and gives a nice performance
697 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700698
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530699 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700700
Borislav Petkov6276a072013-03-04 21:20:21 +0100701source "arch/x86/xen/Kconfig"
702
703config KVM_GUEST
704 bool "KVM Guest support (including kvmclock)"
705 depends on PARAVIRT
706 select PARAVIRT_CLOCK
707 default y
708 ---help---
709 This option enables various optimizations for running under the KVM
710 hypervisor. It includes a paravirtualized clock, so that instead
711 of relying on a PIT (or probably other) emulation by the
712 underlying device model, the host provides the guest with
713 timing infrastructure such as time of day, and system time
714
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530715config KVM_DEBUG_FS
716 bool "Enable debug information for KVM Guests in debugfs"
717 depends on KVM_GUEST && DEBUG_FS
718 default n
719 ---help---
720 This option enables collection of various statistics for KVM guest.
721 Statistics are displayed in debugfs filesystem. Enabling this option
722 may incur significant overhead.
723
Borislav Petkov6276a072013-03-04 21:20:21 +0100724source "arch/x86/lguest/Kconfig"
725
726config PARAVIRT_TIME_ACCOUNTING
727 bool "Paravirtual steal time accounting"
728 depends on PARAVIRT
729 default n
730 ---help---
731 Select this option to enable fine granularity task steal time
732 accounting. Time spent executing other tasks in parallel with
733 the current vCPU is discounted from the vCPU power. To account for
734 that, there can be a small performance impact.
735
736 If in doubt, say N here.
737
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200738config PARAVIRT_CLOCK
739 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200740
Borislav Petkov6276a072013-03-04 21:20:21 +0100741endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400742
Yinghai Lu08677212010-02-10 01:20:20 -0800743config NO_BOOTMEM
Yinghai Lu774ea0b2010-08-25 13:39:18 -0700744 def_bool y
Yinghai Lu08677212010-02-10 01:20:20 -0800745
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100746source "arch/x86/Kconfig.cpu"
747
748config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100749 def_bool X86_64
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100750 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100751 ---help---
752 Use the IA-PC HPET (High Precision Event Timer) to manage
753 time in preference to the PIT and RTC, if a HPET is
754 present.
755 HPET is the next generation timer replacing legacy 8254s.
756 The HPET provides a stable time base on SMP
757 systems, unlike the TSC, but it is more expensive to access,
758 as it is off-chip. You can find the HPET spec at
759 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100760
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100761 You can safely choose Y here. However, HPET will only be
762 activated if the platform and the BIOS support this feature.
763 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100764
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100765 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100766
767config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100768 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800769 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100770
Jacob Panbb24c472009-09-02 07:37:17 -0700771config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000772 def_bool y if X86_INTEL_MID
773 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100774 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000775 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700776 help
777 APB timer is the replacement for 8254, HPET on X86 MID platforms.
778 The APBT 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. APB timers are always running regardless of CPU
781 C states, they are used as per CPU clockevent device when possible.
782
David Rientjes6a108a12011-01-20 14:44:16 -0800783# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100784# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700785config DMI
786 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800787 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800788 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100789 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700790 Enabled scanning of DMI to identify machine quirks. Say Y
791 here unless you have verified that your setup is not
792 affected by entries in the DMI blacklist. Required by PNP
793 BIOS code.
794
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100795config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700796 bool "Old AMD GART IOMMU support"
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100797 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200798 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100799 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200800 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
801 GART based hardware IOMMUs.
802
803 The GART supports full DMA access for devices with 32-bit access
804 limitations, on systems with more than 3 GB. This is usually needed
805 for USB, sound, many IDE/SATA chipsets and some other devices.
806
807 Newer systems typically have a modern AMD IOMMU, supported via
808 the CONFIG_AMD_IOMMU=y config option.
809
810 In normal configurations this driver is only active when needed:
811 there's more than 3 GB of memory and the system contains a
812 32-bit limited device.
813
814 If unsure, say Y.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100815
816config CALGARY_IOMMU
817 bool "IBM Calgary IOMMU support"
818 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700819 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100820 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100821 Support for hardware IOMMUs in IBM's xSeries x366 and x460
822 systems. Needed to run systems with more than 3GB of memory
823 properly with 32-bit PCI devices that do not support DAC
824 (Double Address Cycle). Calgary also supports bus level
825 isolation, where all DMAs pass through the IOMMU. This
826 prevents them from going anywhere except their intended
827 destination. This catches hard-to-find kernel bugs and
828 mis-behaving drivers and devices that do not use the DMA-API
829 properly to set up their DMA buffers. The IOMMU can be
830 turned off at boot time with the iommu=off parameter.
831 Normally the kernel will make the right choice by itself.
832 If unsure, say Y.
833
834config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100835 def_bool y
836 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100837 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100838 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100839 Should Calgary be enabled by default? if you choose 'y', Calgary
840 will be used (if it exists). If you choose 'n', Calgary will not be
841 used even if it exists. If you choose 'n' and would like to use
842 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
843 If unsure, say Y.
844
845# need this always selected by IOMMU for the VIA workaround
846config SWIOTLB
Joerg Roedela1afd012008-11-18 12:44:21 +0100847 def_bool y if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100848 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100849 Support for software bounce buffers used on x86-64 systems
Joe Millenbach4454d322012-09-02 17:38:20 -0700850 which don't have a hardware IOMMU. Using this PCI devices
851 which can only access 32-bits of memory can be used on systems
852 with more than 3 GB of memory.
853 If unsure, say Y.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100854
FUJITA Tomonoria8522502008-04-29 00:59:36 -0700855config IOMMU_HELPER
Jan Beulich3120e252012-09-10 12:41:45 +0100856 def_bool y
857 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
Linus Torvaldsd25e26b2008-08-25 14:15:38 -0700858
Mike Travis1184dc22008-05-12 21:21:12 +0200859config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200860 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700861 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800862 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100863 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200864 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200865 If unsure, say N.
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100866
867config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800868 int "Maximum number of CPUs" if SMP && !MAXSMP
Michael K. Johnson2a3313f2009-04-21 21:44:48 -0400869 range 2 8 if SMP && X86_32 && !X86_BIGSMP
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500870 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
Josh Boyerb53b5ed2013-11-05 09:38:16 -0500871 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
Mike Travis78637a972008-12-16 17:34:00 -0800872 default "1" if !SMP
Josh Boyerb53b5ed2013-11-05 09:38:16 -0500873 default "8192" if MAXSMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800874 default "32" if SMP && X86_BIGSMP
Kirill A. Shutemovc5c19942015-05-08 13:25:45 +0300875 default "8" if SMP && X86_32
876 default "64" if SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100877 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100878 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500879 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +0300880 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100881 minimum value which makes sense is 2.
882
883 This is purely to save memory - each supported CPU adds
884 approximately eight kilobytes to the kernel image.
885
886config SCHED_SMT
887 bool "SMT (Hyperthreading) scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +0200888 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100889 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100890 SMT scheduler support improves the CPU scheduler's decision making
891 when dealing with Intel Pentium 4 chips with HyperThreading at a
892 cost of slightly increased overhead in some places. If unsure say
893 N here.
894
895config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100896 def_bool y
897 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +0200898 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100899 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100900 Multi-core scheduler support improves the CPU scheduler's decision
901 making when dealing with multi-core CPU chips at a cost of slightly
902 increased overhead in some places. If unsure say N here.
903
904source "kernel/Kconfig.preempt"
905
Thomas Gleixner30b8b002015-01-15 21:22:39 +0000906config UP_LATE_INIT
907 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +0100908 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +0000909
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100910config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +0000911 bool "Local APIC support on uniprocessors" if !PCI_MSI
912 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +0000913 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100914 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100915 A local APIC (Advanced Programmable Interrupt Controller) is an
916 integrated interrupt controller in the CPU. If you have a single-CPU
917 system which has a processor with a local APIC, you can say Y here to
918 enable and use it. If you say Y here even though your machine doesn't
919 have a local APIC, then the kernel will still run with no slowdown at
920 all. The local APIC supports CPU-generated self-interrupts (timer,
921 performance counters), and the NMI watchdog which detects hard
922 lockups.
923
924config X86_UP_IOAPIC
925 bool "IO-APIC support on uniprocessors"
926 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100927 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100928 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
929 SMP-capable replacement for PC-style interrupt controllers. Most
930 SMP systems and many recent uniprocessor systems have one.
931
932 If you have a single-CPU system with an IO-APIC, you can say Y here
933 to use it. If you say Y here even though your machine doesn't have
934 an IO-APIC, then the kernel will still run with no slowdown at all.
935
936config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100937 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +0200938 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +0800939 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +0800940 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100941
942config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +0000943 def_bool y
944 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100945
Stefan Assmann41b9eb22008-07-15 13:48:55 +0200946config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
947 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +0200948 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100949 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +0200950 This option enables a workaround that fixes a source of
951 spurious interrupts. This is recommended when threaded
952 interrupt handling is used on systems where the generation of
953 superfluous "boot interrupts" cannot be disabled.
954
955 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
956 entry in the chipset's IO-APIC is masked (as, e.g. the RT
957 kernel does during interrupt handling). On chipsets where this
958 boot IRQ generation cannot be disabled, this workaround keeps
959 the original IRQ line masked so that only the equivalent "boot
960 IRQ" is delivered to the CPUs. The workaround also tells the
961 kernel to set up the IRQ handler on the boot IRQ line. In this
962 way only one interrupt is delivered to the kernel. Otherwise
963 the spurious second interrupt may cause the kernel to bring
964 down (vital) interrupt lines.
965
966 Only affects "broken" chipsets. Interrupt sharing may be
967 increased on these systems.
968
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100969config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +0200970 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +0200971 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +0200972 default y
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100973 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +0200974 Machine Check support allows the processor to notify the
975 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100976 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +0200977 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +0200978
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100979config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100980 def_bool y
981 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +0200982 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100983 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100984 Additional support for intel specific MCE features such as
985 the thermal monitor.
986
987config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100988 def_bool y
989 prompt "AMD MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +0200990 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100991 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +0100992 Additional support for AMD specific MCE features such as
993 the DRAM Error Threshold.
994
Andi Kleen4efc0672009-04-28 19:07:31 +0200995config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100996 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +0200997 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +0900998 ---help---
999 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001000 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001001 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001002
Andi Kleenb2762682009-02-12 13:49:31 +01001003config X86_MCE_THRESHOLD
1004 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001005 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001006
Andi Kleenea149b32009-04-29 19:31:00 +02001007config X86_MCE_INJECT
Andi Kleenc1ebf832009-07-09 00:31:41 +02001008 depends on X86_MCE
Andi Kleenea149b32009-04-29 19:31:00 +02001009 tristate "Machine check injector support"
1010 ---help---
1011 Provide support for injecting machine checks for testing purposes.
1012 If you don't know what a machine check is and you don't do kernel
1013 QA it is safe to say n.
1014
Andi Kleen4efc0672009-04-28 19:07:31 +02001015config X86_THERMAL_VECTOR
1016 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001017 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001018
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001019config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001020 bool "Legacy VM86 support"
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001021 default n
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001022 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001023 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001024 This option allows user programs to put the CPU into V8086
1025 mode, which is an 80286-era approximation of 16-bit real mode.
1026
1027 Some very old versions of X and/or vbetool require this option
1028 for user mode setting. Similarly, DOSEMU will use it if
1029 available to accelerate real mode DOS programs. However, any
1030 recent version of DOSEMU, X, or vbetool should be fully
1031 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001032 fall back to software emulation. Nevertheless, if you are using
1033 a 16-bit DOS program where 16-bit performance matters, vm86
1034 mode might be faster than emulation and you might want to
1035 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001036
Ingo Molnar1e642812015-09-05 08:58:10 +02001037 Note that any app that works on a 64-bit kernel is unlikely to
1038 need this option, as 64-bit kernels don't, and can't, support
1039 V8086 mode. This option is also unrelated to 16-bit protected
1040 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001041
Ingo Molnar1e642812015-09-05 08:58:10 +02001042 Enabling this option increases the complexity of the kernel
1043 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001044
Ingo Molnar1e642812015-09-05 08:58:10 +02001045 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001046
1047config VM86
1048 bool
1049 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001050
1051config X86_16BIT
1052 bool "Enable support for 16-bit segments" if EXPERT
1053 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001054 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001055 ---help---
1056 This option is required by programs like Wine to run 16-bit
1057 protected mode legacy code on x86 processors. Disabling
1058 this option saves about 300 bytes on i386, or around 6K text
1059 plus 16K runtime memory on x86-64,
1060
1061config X86_ESPFIX32
1062 def_bool y
1063 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001064
H. Peter Anvin197725d2014-05-04 10:00:49 -07001065config X86_ESPFIX64
1066 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001067 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001068
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001069config X86_VSYSCALL_EMULATION
1070 bool "Enable vsyscall emulation" if EXPERT
1071 default y
1072 depends on X86_64
1073 ---help---
1074 This enables emulation of the legacy vsyscall page. Disabling
1075 it is roughly equivalent to booting with vsyscall=none, except
1076 that it will also disable the helpful warning if a program
1077 tries to use a vsyscall. With this option set to N, offending
1078 programs will just segfault, citing addresses of the form
1079 0xffffffffff600?00.
1080
1081 This option is required by many programs built before 2013, and
1082 care should be used even with newer programs if set to N.
1083
1084 Disabling this option saves about 7K of kernel size and
1085 possibly 4K of additional runtime pagetable memory.
1086
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001087config TOSHIBA
1088 tristate "Toshiba Laptop support"
1089 depends on X86_32
1090 ---help---
1091 This adds a driver to safely access the System Management Mode of
1092 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1093 not work on models with a Phoenix BIOS. The System Management Mode
1094 is used to set the BIOS and power saving options on Toshiba portables.
1095
1096 For information on utilities to make use of this driver see the
1097 Toshiba Linux utilities web site at:
1098 <http://www.buzzard.org.uk/toshiba/>.
1099
1100 Say Y if you intend to run this kernel on a Toshiba portable.
1101 Say N otherwise.
1102
1103config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001104 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001105 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001106 select SENSORS_DELL_SMM
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001107 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001108 This option enables legacy /proc/i8k userspace interface in hwmon
1109 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1110 temperature and allows controlling fan speeds of Dell laptops via
1111 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1112 it reports also power and hotkey status. For fan speed control is
1113 needed userspace package i8kutils.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001114
Pali Rohár039ae582015-05-14 13:16:37 +02001115 Say Y if you intend to run this kernel on old Dell laptops or want to
1116 use userspace package i8kutils.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001117 Say N otherwise.
1118
1119config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001120 bool "Enable X86 board specific fixups for reboot"
1121 depends on X86_32
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001122 ---help---
1123 This enables chipset and/or board specific fixups to be done
1124 in order to get reboot to work correctly. This is only needed on
1125 some combinations of hardware and BIOS. The symptom, for which
1126 this config is intended, is when reboot ends with a stalled/hung
1127 system.
1128
1129 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001130 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001131
1132 Say Y if you want to enable the fixup. Currently, it's safe to
1133 enable this option even if you don't need it.
1134 Say N otherwise.
1135
1136config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001137 bool "CPU microcode loading support"
1138 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001139 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Borislav Petkovfe055892015-10-20 11:54:45 +02001140 depends on BLK_DEV_INITRD
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001141 select FW_LOADER
1142 ---help---
Borislav Petkove43f6e62012-08-01 19:17:01 +02001143
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001144 If you say Y here, you will be able to update the microcode on
Peter Oruba80cc9f12008-07-28 18:44:22 +02001145 certain Intel and AMD processors. The Intel support is for the
Borislav Petkove43f6e62012-08-01 19:17:01 +02001146 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1147 Xeon etc. The AMD support is for families 0x10 and later. You will
1148 obviously need the actual microcode binary data itself which is not
1149 shipped with the Linux kernel.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001150
Peter Oruba8d86f392008-07-28 18:44:21 +02001151 This option selects the general module only, you need to select
1152 at least one vendor specific module as well.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001153
Borislav Petkove43f6e62012-08-01 19:17:01 +02001154 To compile this driver as a module, choose M here: the module
1155 will be called microcode.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001156
Peter Oruba8d86f392008-07-28 18:44:21 +02001157config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001158 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001159 depends on MICROCODE
1160 default MICROCODE
1161 select FW_LOADER
1162 ---help---
1163 This options enables microcode patch loading support for Intel
1164 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001165
Alanb8989db2014-01-20 18:01:56 +00001166 For the current Intel microcode data package go to
1167 <https://downloadcenter.intel.com> and search for
1168 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001169
Peter Oruba80cc9f12008-07-28 18:44:22 +02001170config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001171 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001172 depends on MICROCODE
1173 select FW_LOADER
1174 ---help---
1175 If you select this option, microcode patch loading support for AMD
1176 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001177
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001178config MICROCODE_OLD_INTERFACE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001179 def_bool y
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001180 depends on MICROCODE
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001181
1182config X86_MSR
1183 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001184 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001185 This device gives privileged processes access to the x86
1186 Model-Specific Registers (MSRs). It is a character device with
1187 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1188 MSR accesses are directed to a specific CPU on multi-processor
1189 systems.
1190
1191config X86_CPUID
1192 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001193 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001194 This device gives processes access to the x86 CPUID instruction to
1195 be executed on a specific processor. It is a character device
1196 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1197 /dev/cpu/31/cpuid.
1198
1199choice
1200 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001201 default HIGHMEM4G
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001202 depends on X86_32
1203
1204config NOHIGHMEM
1205 bool "off"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001206 ---help---
1207 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1208 However, the address space of 32-bit x86 processors is only 4
1209 Gigabytes large. That means that, if you have a large amount of
1210 physical memory, not all of it can be "permanently mapped" by the
1211 kernel. The physical memory that's not permanently mapped is called
1212 "high memory".
1213
1214 If you are compiling a kernel which will never run on a machine with
1215 more than 1 Gigabyte total physical RAM, answer "off" here (default
1216 choice and suitable for most users). This will result in a "3GB/1GB"
1217 split: 3GB are mapped so that each process sees a 3GB virtual memory
1218 space and the remaining part of the 4GB virtual memory space is used
1219 by the kernel to permanently map as much physical memory as
1220 possible.
1221
1222 If the machine has between 1 and 4 Gigabytes physical RAM, then
1223 answer "4GB" here.
1224
1225 If more than 4 Gigabytes is used then answer "64GB" here. This
1226 selection turns Intel PAE (Physical Address Extension) mode on.
1227 PAE implements 3-level paging on IA32 processors. PAE is fully
1228 supported by Linux, PAE mode is implemented on all recent Intel
1229 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1230 then the kernel will not boot on CPUs that don't support PAE!
1231
1232 The actual amount of total physical memory will either be
1233 auto detected or can be forced by using a kernel command line option
1234 such as "mem=256M". (Try "man bootparam" or see the documentation of
1235 your boot loader (lilo or loadlin) about how to pass options to the
1236 kernel at boot time.)
1237
1238 If unsure, say "off".
1239
1240config HIGHMEM4G
1241 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001242 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001243 Select this if you have a 32-bit processor and between 1 and 4
1244 gigabytes of physical RAM.
1245
1246config HIGHMEM64G
1247 bool "64GB"
H. Peter Anvineb068e72012-11-28 11:50:23 -08001248 depends on !M486
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001249 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001250 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001251 Select this if you have a 32-bit processor and more than 4
1252 gigabytes of physical RAM.
1253
1254endchoice
1255
1256choice
David Rientjes6a108a12011-01-20 14:44:16 -08001257 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001258 default VMSPLIT_3G
1259 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001260 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001261 Select the desired split between kernel and user memory.
1262
1263 If the address range available to the kernel is less than the
1264 physical memory installed, the remaining memory will be available
1265 as "high memory". Accessing high memory is a little more costly
1266 than low memory, as it needs to be mapped into the kernel first.
1267 Note that increasing the kernel address space limits the range
1268 available to user programs, making the address space there
1269 tighter. Selecting anything other than the default 3G/1G split
1270 will also likely make your kernel incompatible with binary-only
1271 kernel modules.
1272
1273 If you are not absolutely sure what you are doing, leave this
1274 option alone!
1275
1276 config VMSPLIT_3G
1277 bool "3G/1G user/kernel split"
1278 config VMSPLIT_3G_OPT
1279 depends on !X86_PAE
1280 bool "3G/1G user/kernel split (for full 1G low memory)"
1281 config VMSPLIT_2G
1282 bool "2G/2G user/kernel split"
1283 config VMSPLIT_2G_OPT
1284 depends on !X86_PAE
1285 bool "2G/2G user/kernel split (for full 2G low memory)"
1286 config VMSPLIT_1G
1287 bool "1G/3G user/kernel split"
1288endchoice
1289
1290config PAGE_OFFSET
1291 hex
1292 default 0xB0000000 if VMSPLIT_3G_OPT
1293 default 0x80000000 if VMSPLIT_2G
1294 default 0x78000000 if VMSPLIT_2G_OPT
1295 default 0x40000000 if VMSPLIT_1G
1296 default 0xC0000000
1297 depends on X86_32
1298
1299config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001300 def_bool y
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001301 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001302
1303config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001304 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001305 depends on X86_32 && !HIGHMEM4G
Christian Melki9d99c712015-10-05 17:31:33 +02001306 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001307 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001308 PAE is required for NX support, and furthermore enables
1309 larger swapspace support for non-overcommit purposes. It
1310 has the cost of more pagetable lookup overhead, and also
1311 consumes more pagetable space per process.
1312
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001313config ARCH_PHYS_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001314 def_bool y
1315 depends on X86_64 || X86_PAE
Jeremy Fitzhardinge600715d2008-09-11 01:31:45 -07001316
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001317config ARCH_DMA_ADDR_T_64BIT
Jan Beulich3120e252012-09-10 12:41:45 +01001318 def_bool y
1319 depends on X86_64 || HIGHMEM64G
FUJITA Tomonori66f2b062010-10-20 15:55:35 -07001320
Ingo Molnar10971ab2015-03-05 08:18:23 +01001321config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001322 def_bool y
1323 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001324 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001325 Certain kernel features effectively disable kernel
1326 linear 1 GB mappings (even if the CPU otherwise
1327 supports them), so don't confuse the user by printing
1328 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001329
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001330# Common NUMA Features
1331config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001332 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001333 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001334 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1335 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001336 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001337 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001338
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001339 The kernel will try to allocate memory used by a CPU on the
1340 local memory controller of the CPU and add some more
1341 NUMA awareness to the kernel.
1342
Ingo Molnarc280ea52008-11-08 13:29:45 +01001343 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001344 (or later), AMD Opteron, or EM64T NUMA.
1345
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001346 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001347 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001348
1349 Otherwise, you should say N.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001350
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001351config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001352 def_bool y
1353 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001354 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001355 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001356 Enable AMD NUMA node topology detection. You should say Y here if
1357 you have a multi processor AMD system. This uses an old method to
1358 read the NUMA configuration directly from the builtin Northbridge
1359 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1360 which also takes priority if both are compiled in.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001361
1362config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001363 def_bool y
1364 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001365 depends on X86_64 && NUMA && ACPI && PCI
1366 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001367 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001368 Enable ACPI SRAT based node topology detection.
1369
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001370# Some NUMA nodes have memory ranges that span
1371# other nodes. Even though a pfn is valid and
1372# between a node's start and end pfns, it may not
1373# reside on that node. See memmap_init_zone()
1374# for details.
1375config NODES_SPAN_OTHER_NODES
1376 def_bool y
1377 depends on X86_64_ACPI_NUMA
1378
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001379config NUMA_EMU
1380 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001381 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001382 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001383 Enable NUMA emulation. A flat machine will be split
1384 into virtual nodes when booted with "numa=fake=N", where N is the
1385 number of nodes. This is only useful for debugging.
1386
1387config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001388 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001389 range 1 10
1390 default "10" if MAXSMP
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001391 default "6" if X86_64
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001392 default "3"
1393 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001394 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001395 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001396 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001397
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001398config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001399 def_bool y
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001400 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001401
1402config NEED_NODE_MEMMAP_SIZE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001403 def_bool y
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001404 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001405
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001406config ARCH_FLATMEM_ENABLE
1407 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001408 depends on X86_32 && !NUMA
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001409
1410config ARCH_DISCONTIGMEM_ENABLE
1411 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001412 depends on NUMA && X86_32
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001413
1414config ARCH_DISCONTIGMEM_DEFAULT
1415 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001416 depends on NUMA && X86_32
1417
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001418config ARCH_SPARSEMEM_ENABLE
1419 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001420 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001421 select SPARSEMEM_STATIC if X86_32
1422 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1423
Tejun Heo3b166512011-04-01 11:15:12 +02001424config ARCH_SPARSEMEM_DEFAULT
1425 def_bool y
1426 depends on X86_64
1427
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001428config ARCH_SELECT_MEMORY_MODEL
1429 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001430 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001431
1432config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001433 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001434 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001435 help
1436 This option enables a sysfs memory/probe interface for testing.
1437 See Documentation/memory-hotplug.txt for more information.
1438 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001439
Tejun Heo3b166512011-04-01 11:15:12 +02001440config ARCH_PROC_KCORE_TEXT
1441 def_bool y
1442 depends on X86_64 && PROC_KCORE
1443
Avi Kivitya29815a2010-01-10 16:28:09 +02001444config ILLEGAL_POINTER_VALUE
1445 hex
1446 default 0 if X86_32
1447 default 0xdead000000000000 if X86_64
1448
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001449source "mm/Kconfig"
1450
Dan Williams7a678322015-08-19 00:34:34 -04001451config X86_PMEM_LEGACY_DEVICE
1452 bool
1453
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001454config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001455 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001456 depends on PHYS_ADDR_T_64BIT
1457 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001458 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001459 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001460 help
1461 Treat memory marked using the non-standard e820 type of 12 as used
1462 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1463 The kernel will offer these regions to the 'pmem' driver so
1464 they can be used for persistent storage.
1465
1466 Say Y if unsure.
1467
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001468config HIGHPTE
1469 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001470 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001471 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001472 The VM uses one page table entry for each page of physical memory.
1473 For systems with a lot of RAM, this can be wasteful of precious
1474 low memory. Setting this option will put user-space page table
1475 entries in high memory.
1476
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001477config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001478 bool "Check for low memory corruption"
1479 ---help---
1480 Periodically check for memory corruption in low memory, which
1481 is suspected to be caused by BIOS. Even when enabled in the
1482 configuration, it is disabled at runtime. Enable it by
1483 setting "memory_corruption_check=1" on the kernel command
1484 line. By default it scans the low 64k of memory every 60
1485 seconds; see the memory_corruption_check_size and
1486 memory_corruption_check_period parameters in
1487 Documentation/kernel-parameters.txt to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001488
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001489 When enabled with the default parameters, this option has
1490 almost no overhead, as it reserves a relatively small amount
1491 of memory and scans it infrequently. It both detects corruption
1492 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001493
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001494 It is, however, intended as a diagnostic tool; if repeatable
1495 BIOS-originated corruption always affects the same memory,
1496 you can use memmap= to prevent the kernel from using that
1497 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001498
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001499config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001500 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001501 depends on X86_CHECK_BIOS_CORRUPTION
1502 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001503 ---help---
1504 Set whether the default state of memory_corruption_check is
1505 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001506
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001507config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001508 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1509 default 64
1510 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001511 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001512 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001513
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001514 The first page contains BIOS data structures that the kernel
1515 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001516
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001517 By default we reserve the first 64K of physical RAM, as a
1518 number of BIOSes are known to corrupt that memory range
1519 during events such as suspend/resume or monitor cable
1520 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001521
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001522 You can set this to 4 if you are absolutely sure that you
1523 trust the BIOS to get all its memory reservations and usages
1524 right. If you know your BIOS have problems beyond the
1525 default 64K area, you can set this to 640 to avoid using the
1526 entire low memory range.
1527
1528 If you have doubts about the BIOS (e.g. suspend/resume does
1529 not work or there's kernel crashes after certain hardware
1530 hotplug events) then you might want to enable
1531 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1532 typical corruption patterns.
1533
1534 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001535
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001536config MATH_EMULATION
1537 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001538 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001539 prompt "Math emulation" if X86_32
1540 ---help---
1541 Linux can emulate a math coprocessor (used for floating point
1542 operations) if you don't have one. 486DX and Pentium processors have
1543 a math coprocessor built in, 486SX and 386 do not, unless you added
1544 a 487DX or 387, respectively. (The messages during boot time can
1545 give you some hints here ["man dmesg"].) Everyone needs either a
1546 coprocessor or this emulation.
1547
1548 If you don't have a math coprocessor, you need to say Y here; if you
1549 say Y here even though you have a coprocessor, the coprocessor will
1550 be used nevertheless. (This behavior can be changed with the kernel
1551 command line option "no387", which comes handy if your coprocessor
1552 is broken. Try "man bootparam" or see the documentation of your boot
1553 loader (lilo or loadlin) about how to pass options to the kernel at
1554 boot time.) This means that it is a good idea to say Y here if you
1555 intend to use this kernel on different machines.
1556
1557 More information about the internals of the Linux math coprocessor
1558 emulation can be found in <file:arch/x86/math-emu/README>.
1559
1560 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1561 kernel, it won't hurt.
1562
1563config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001564 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001565 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001566 ---help---
1567 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1568 the Memory Type Range Registers (MTRRs) may be used to control
1569 processor access to memory ranges. This is most useful if you have
1570 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1571 allows bus write transfers to be combined into a larger transfer
1572 before bursting over the PCI/AGP bus. This can increase performance
1573 of image write operations 2.5 times or more. Saying Y here creates a
1574 /proc/mtrr file which may be used to manipulate your processor's
1575 MTRRs. Typically the X server should use this.
1576
1577 This code has a reasonably generic interface so that similar
1578 control registers on other processors can be easily supported
1579 as well:
1580
1581 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1582 Registers (ARRs) which provide a similar functionality to MTRRs. For
1583 these, the ARRs are used to emulate the MTRRs.
1584 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1585 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1586 write-combining. All of these processors are supported by this code
1587 and it makes sense to say Y here if you have one of them.
1588
1589 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1590 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1591 can lead to all sorts of problems, so it's good to say Y here.
1592
1593 You can safely say Y even if your machine doesn't have MTRRs, you'll
1594 just add about 9 KB to your kernel.
1595
Randy Dunlap7225e752008-07-26 17:54:22 -07001596 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001597
Yinghai Lu95ffa242008-04-29 03:52:33 -07001598config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001599 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001600 prompt "MTRR cleanup support"
1601 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001602 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001603 Convert MTRR layout from continuous to discrete, so X drivers can
1604 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001605
Thomas Gleixneraba37282008-07-15 14:48:48 +02001606 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001607 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001608 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001609
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001610 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001611
1612config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001613 int "MTRR cleanup enable value (0-1)"
1614 range 0 1
1615 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001616 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001617 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001618 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001619
Yinghai Lu12031a62008-05-02 02:40:22 -07001620config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1621 int "MTRR cleanup spare reg num (0-7)"
1622 range 0 7
1623 default "1"
1624 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001625 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001626 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001627 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001628
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001629config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001630 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001631 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001632 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001633 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001634 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001635
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001636 PATs are the modern equivalents of MTRRs and are much more
1637 flexible than MTRRs.
1638
1639 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001640 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001641
1642 If unsure, say Y.
1643
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001644config ARCH_USES_PG_UNCACHED
1645 def_bool y
1646 depends on X86_PAT
1647
H. Peter Anvin628c6242011-07-31 13:59:29 -07001648config ARCH_RANDOM
1649 def_bool y
1650 prompt "x86 architectural random number generator" if EXPERT
1651 ---help---
1652 Enable the x86 architectural RDRAND instruction
1653 (Intel Bull Mountain technology) to generate random numbers.
1654 If supported, this is a high bandwidth, cryptographically
1655 secure hardware random number generator.
1656
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001657config X86_SMAP
1658 def_bool y
1659 prompt "Supervisor Mode Access Prevention" if EXPERT
1660 ---help---
1661 Supervisor Mode Access Prevention (SMAP) is a security
1662 feature in newer Intel processors. There is a small
1663 performance cost if this enabled and turned on; there is
1664 also a small increase in the kernel size if this is enabled.
1665
1666 If unsure, say Y.
1667
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001668config X86_INTEL_MPX
1669 prompt "Intel MPX (Memory Protection Extensions)"
1670 def_bool n
1671 depends on CPU_SUP_INTEL
1672 ---help---
1673 MPX provides hardware features that can be used in
1674 conjunction with compiler-instrumented code to check
1675 memory references. It is designed to detect buffer
1676 overflow or underflow bugs.
1677
1678 This option enables running applications which are
1679 instrumented or otherwise use MPX. It does not use MPX
1680 itself inside the kernel or to protect the kernel
1681 against bad memory references.
1682
1683 Enabling this option will make the kernel larger:
1684 ~8k of kernel text and 36 bytes of data on a 64-bit
1685 defconfig. It adds a long to the 'mm_struct' which
1686 will increase the kernel memory overhead of each
1687 process and adds some branches to paths used during
1688 exec() and munmap().
1689
1690 For details, see Documentation/x86/intel_mpx.txt
1691
1692 If unsure, say N.
1693
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001694config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001695 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001696 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001697 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001698 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001699 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001700 This enables the kernel to use EFI runtime services that are
1701 available (such as the EFI variable services).
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001702
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001703 This option is only useful on systems that have EFI firmware.
1704 In addition, you should use the latest ELILO loader available
1705 at <http://elilo.sourceforge.net> in order to take advantage
1706 of EFI runtime services. However, even with this option, the
1707 resultant kernel should continue to boot on existing non-EFI
1708 platforms.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001709
Matt Fleming291f3632011-12-12 21:27:52 +00001710config EFI_STUB
1711 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001712 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001713 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001714 ---help---
1715 This kernel feature allows a bzImage to be loaded directly
1716 by EFI firmware without the use of a bootloader.
1717
Roy Franz4172fe22013-09-22 15:45:25 -07001718 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001719
Matt Fleming7d453ee2014-01-10 18:52:06 +00001720config EFI_MIXED
1721 bool "EFI mixed-mode support"
1722 depends on EFI_STUB && X86_64
1723 ---help---
1724 Enabling this feature allows a 64-bit kernel to be booted
1725 on a 32-bit firmware, provided that your CPU supports 64-bit
1726 mode.
1727
1728 Note that it is not possible to boot a mixed-mode enabled
1729 kernel via the EFI boot stub - a bootloader that supports
1730 the EFI handover protocol must be used.
1731
1732 If unsure, say N.
1733
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001734config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001735 def_bool y
1736 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001737 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001738 This kernel feature is useful for number crunching applications
1739 that may need to compute untrusted bytecode during their
1740 execution. By using pipes or other transports made available to
1741 the process as file descriptors supporting the read/write
1742 syscalls, it's possible to isolate those applications in
1743 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001744 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001745 and the task is only allowed to execute a few safe syscalls
1746 defined by each seccomp mode.
1747
1748 If unsure, say Y. Only embedded should say N here.
1749
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001750source kernel/Kconfig.hz
1751
1752config KEXEC
1753 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001754 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001755 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001756 kexec is a system call that implements the ability to shutdown your
1757 current kernel, and to start another kernel. It is like a reboot
1758 but it is independent of the system firmware. And like a reboot
1759 you can start any kernel with it, not just Linux.
1760
1761 The name comes from the similarity to the exec system call.
1762
1763 It is an ongoing process to be certain the hardware in a machine
1764 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001765 initially work for you. As of this writing the exact hardware
1766 interface is strongly in flux, so no good recommendation can be
1767 made.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001768
Vivek Goyal74ca3172014-08-29 15:18:46 -07001769config KEXEC_FILE
1770 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07001771 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07001772 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07001773 depends on X86_64
1774 depends on CRYPTO=y
1775 depends on CRYPTO_SHA256=y
1776 ---help---
1777 This is new version of kexec system call. This system call is
1778 file based and takes file descriptors as system call argument
1779 for kernel and initramfs as opposed to list of segments as
1780 accepted by previous system call.
1781
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001782config KEXEC_VERIFY_SIG
1783 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07001784 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001785 ---help---
1786 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01001787 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001788
Borislav Petkovd8eb8942015-03-13 14:04:37 +01001789 In addition to that option, you need to enable signature
1790 verification for the corresponding kernel image type being
1791 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07001792
1793config KEXEC_BZIMAGE_VERIFY_SIG
1794 bool "Enable bzImage signature verification support"
1795 depends on KEXEC_VERIFY_SIG
1796 depends on SIGNED_PE_FILE_VERIFICATION
1797 select SYSTEM_TRUSTED_KEYRING
1798 ---help---
1799 Enable bzImage signature verification support.
1800
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001801config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02001802 bool "kernel crash dumps"
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001803 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001804 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001805 Generate crash dump after being started by kexec.
1806 This should be normally only set in special crash dump kernels
1807 which are loaded in the main kernel with kexec-tools into
1808 a specially reserved region and then later executed after
1809 a crash by kdump/kexec. The crash dump kernel must be compiled
1810 to a memory address not used by the main kernel or BIOS using
1811 PHYSICAL_START, or it must be built as a relocatable image
1812 (CONFIG_RELOCATABLE=y).
1813 For more details see Documentation/kdump/kdump.txt
1814
Huang Ying3ab83522008-07-25 19:45:07 -07001815config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07001816 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08001817 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001818 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07001819 Jump between original kernel and kexeced kernel and invoke
1820 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07001821
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001822config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08001823 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07001824 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001825 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001826 This gives the physical address where the kernel is loaded.
1827
1828 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1829 bzImage will decompress itself to above physical address and
1830 run from there. Otherwise, bzImage will run from the address where
1831 it has been loaded by the boot loader and will ignore above physical
1832 address.
1833
1834 In normal kdump cases one does not have to set/change this option
1835 as now bzImage can be compiled as a completely relocatable image
1836 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1837 address. This option is mainly useful for the folks who don't want
1838 to use a bzImage for capturing the crash dump and want to use a
1839 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1840 to be specifically compiled to run from a specific memory area
1841 (normally a reserved region) and this option comes handy.
1842
H. Peter Anvinceefccc2009-05-11 16:12:16 -07001843 So if you are using bzImage for capturing the crash dump,
1844 leave the value here unchanged to 0x1000000 and set
1845 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1846 for capturing the crash dump change this value to start of
1847 the reserved region. In other words, it can be set based on
1848 the "X" value as specified in the "crashkernel=YM@XM"
1849 command line boot parameter passed to the panic-ed
1850 kernel. Please take a look at Documentation/kdump/kdump.txt
1851 for more details about crash dumps.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001852
1853 Usage of bzImage for capturing the crash dump is recommended as
1854 one does not have to build two kernels. Same kernel can be used
1855 as production kernel and capture kernel. Above option should have
1856 gone away after relocatable bzImage support is introduced. But it
1857 is present because there are users out there who continue to use
1858 vmlinux for dump capture. This option should go away down the
1859 line.
1860
1861 Don't change this unless you know what you are doing.
1862
1863config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07001864 bool "Build a relocatable kernel"
1865 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001866 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001867 This builds a kernel image that retains relocation information
1868 so it can be loaded someplace besides the default 1MB.
1869 The relocations tend to make the kernel binary about 10% larger,
1870 but are discarded at runtime.
1871
1872 One use is for the kexec on panic case where the recovery kernel
1873 must live at a different physical address than the primary
1874 kernel.
1875
1876 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1877 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07001878 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001879
Kees Cook8ab38202013-10-10 17:18:14 -07001880config RANDOMIZE_BASE
1881 bool "Randomize the address of the kernel image"
1882 depends on RELOCATABLE
Kees Cook8ab38202013-10-10 17:18:14 -07001883 default n
1884 ---help---
1885 Randomizes the physical and virtual address at which the
1886 kernel image is decompressed, as a security feature that
1887 deters exploit attempts relying on knowledge of the location
1888 of kernel internals.
1889
Kees Cooka653f352013-11-11 14:28:39 -08001890 Entropy is generated using the RDRAND instruction if it is
1891 supported. If RDTSC is supported, it is used as well. If
1892 neither RDRAND nor RDTSC are supported, then randomness is
1893 read from the i8254 timer.
Kees Cook8ab38202013-10-10 17:18:14 -07001894
1895 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
Kees Cooka653f352013-11-11 14:28:39 -08001896 and aligned according to PHYSICAL_ALIGN. Since the kernel is
1897 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1898 minimum of 2MiB, only 10 bits of entropy is theoretically
1899 possible. At best, due to page table layouts, 64-bit can use
1900 9 bits of entropy and 32-bit uses 8 bits.
Kees Cook8ab38202013-10-10 17:18:14 -07001901
Kees Cookda2b6fb2013-12-10 12:27:45 -08001902 If unsure, say N.
1903
Kees Cook8ab38202013-10-10 17:18:14 -07001904config RANDOMIZE_BASE_MAX_OFFSET
Kees Cookda2b6fb2013-12-10 12:27:45 -08001905 hex "Maximum kASLR offset allowed" if EXPERT
Kees Cook8ab38202013-10-10 17:18:14 -07001906 depends on RANDOMIZE_BASE
Kees Cook6145cfe2013-10-10 17:18:18 -07001907 range 0x0 0x20000000 if X86_32
1908 default "0x20000000" if X86_32
1909 range 0x0 0x40000000 if X86_64
1910 default "0x40000000" if X86_64
Kees Cook8ab38202013-10-10 17:18:14 -07001911 ---help---
Kees Cookda2b6fb2013-12-10 12:27:45 -08001912 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1913 memory is used to determine the maximal offset in bytes that will
1914 be applied to the kernel when kernel Address Space Layout
1915 Randomization (kASLR) is active. This must be a multiple of
1916 PHYSICAL_ALIGN.
Kees Cook6145cfe2013-10-10 17:18:18 -07001917
Kees Cookda2b6fb2013-12-10 12:27:45 -08001918 On 32-bit this is limited to 512MiB by page table layouts. The
1919 default is 512MiB.
Kees Cook6145cfe2013-10-10 17:18:18 -07001920
Kees Cookda2b6fb2013-12-10 12:27:45 -08001921 On 64-bit this is limited by how the kernel fixmap page table is
1922 positioned, so this cannot be larger than 1GiB currently. Without
1923 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1924 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1925 modules area will shrink to compensate, up to the current maximum
1926 1GiB to 1GiB split. The default is 1GiB.
1927
1928 If unsure, leave at the default value.
Kees Cook8ab38202013-10-10 17:18:14 -07001929
1930# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07001931config X86_NEED_RELOCS
1932 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07001933 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07001934
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001935config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07001936 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07001937 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07001938 range 0x2000 0x1000000 if X86_32
1939 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001940 ---help---
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001941 This value puts the alignment restrictions on physical address
1942 where kernel is loaded and run from. Kernel is compiled for an
1943 address which meets above alignment restriction.
1944
1945 If bootloader loads the kernel at a non-aligned address and
1946 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1947 address aligned to above value and run from there.
1948
1949 If bootloader loads the kernel at a non-aligned address and
1950 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1951 load address and decompress itself to the address it has been
1952 compiled for and run from there. The address for which kernel is
1953 compiled already meets above alignment restrictions. Hence the
1954 end result is that kernel runs from a physical address meeting
1955 above alignment restrictions.
1956
Kees Cooka0215062013-07-08 09:15:17 -07001957 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1958 this value must be a multiple of 0x200000.
1959
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001960 Don't change this unless you know what you are doing.
1961
1962config HOTPLUG_CPU
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05001963 bool "Support for hot-pluggable CPUs"
Stephen Rothwell40b31362013-05-21 13:49:35 +10001964 depends on SMP
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001965 ---help---
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05001966 Say Y here to allow turning CPUs off and on. CPUs can be
1967 controlled through /sys/devices/system/cpu.
1968 ( Note: power management support will enable this option
1969 automatically on SMP systems. )
1970 Say N if you want to disable CPU hotplug.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01001971
Fenghua Yu80aa1df2012-11-13 11:32:39 -08001972config BOOTPARAM_HOTPLUG_CPU0
1973 bool "Set default setting of cpu0_hotpluggable"
1974 default n
Kees Cook2c922cd2013-01-22 13:01:19 -08001975 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08001976 ---help---
1977 Set whether default state of cpu0_hotpluggable is on or off.
1978
1979 Say Y here to enable CPU0 hotplug by default. If this switch
1980 is turned on, there is no need to give cpu0_hotplug kernel
1981 parameter and the CPU0 hotplug feature is enabled by default.
1982
1983 Please note: there are two known CPU0 dependencies if you want
1984 to enable the CPU0 hotplug feature either by this switch or by
1985 cpu0_hotplug kernel parameter.
1986
1987 First, resume from hibernate or suspend always starts from CPU0.
1988 So hibernate and suspend are prevented if CPU0 is offline.
1989
1990 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1991 offline if any interrupt can not migrate out of CPU0. There may
1992 be other CPU0 dependencies.
1993
1994 Please make sure the dependencies are under your control before
1995 you enable this feature.
1996
1997 Say N if you don't want to enable CPU0 hotplug feature by default.
1998 You still can enable the CPU0 hotplug feature at boot by kernel
1999 parameter cpu0_hotplug.
2000
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002001config DEBUG_HOTPLUG_CPU0
2002 def_bool n
2003 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002004 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002005 ---help---
2006 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2007 soon as possible and boots up userspace with CPU0 offlined. User
2008 can online CPU0 back after boot time.
2009
2010 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2011 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2012 compilation or giving cpu0_hotplug kernel parameter at boot.
2013
2014 If unsure, say N.
2015
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002016config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002017 def_bool n
2018 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Roland McGrathaf65d642008-01-30 13:30:43 +01002019 depends on X86_32 || IA32_EMULATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002020 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002021 Certain buggy versions of glibc will crash if they are
2022 presented with a 32-bit vDSO that is not mapped at the address
2023 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002024
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002025 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2026 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2027 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2028 the only released version with the bug, but OpenSUSE 9
2029 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002030
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002031 The symptom of the bug is that everything crashes on startup, saying:
2032 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2033
2034 Saying Y here changes the default value of the vdso32 boot
2035 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2036 This works around the glibc bug but hurts performance.
2037
2038 If unsure, say N: if you are compiling your own kernel, you
2039 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002040
Kees Cook3dc33bd2015-08-12 17:55:19 -07002041choice
2042 prompt "vsyscall table for legacy applications"
2043 depends on X86_64
2044 default LEGACY_VSYSCALL_EMULATE
2045 help
2046 Legacy user code that does not know how to find the vDSO expects
2047 to be able to issue three syscalls by calling fixed addresses in
2048 kernel space. Since this location is not randomized with ASLR,
2049 it can be used to assist security vulnerability exploitation.
2050
2051 This setting can be changed at boot time via the kernel command
2052 line parameter vsyscall=[native|emulate|none].
2053
2054 On a system with recent enough glibc (2.14 or newer) and no
2055 static binaries, you can say None without a performance penalty
2056 to improve security.
2057
2058 If unsure, select "Emulate".
2059
2060 config LEGACY_VSYSCALL_NATIVE
2061 bool "Native"
2062 help
2063 Actual executable code is located in the fixed vsyscall
2064 address mapping, implementing time() efficiently. Since
2065 this makes the mapping executable, it can be used during
2066 security vulnerability exploitation (traditionally as
2067 ROP gadgets). This configuration is not recommended.
2068
2069 config LEGACY_VSYSCALL_EMULATE
2070 bool "Emulate"
2071 help
2072 The kernel traps and emulates calls into the fixed
2073 vsyscall address mapping. This makes the mapping
2074 non-executable, but it still contains known contents,
2075 which could be used in certain rare security vulnerability
2076 exploits. This configuration is recommended when userspace
2077 still uses the vsyscall area.
2078
2079 config LEGACY_VSYSCALL_NONE
2080 bool "None"
2081 help
2082 There will be no vsyscall mapping at all. This will
2083 eliminate any risk of ASLR bypass due to the vsyscall
2084 fixed address mapping. Attempts to use the vsyscalls
2085 will be reported to dmesg, so that either old or
2086 malicious userspace programs can be identified.
2087
2088endchoice
2089
Tim Bird516cbf32008-08-12 12:52:36 -07002090config CMDLINE_BOOL
2091 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002092 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002093 Allow for specifying boot arguments to the kernel at
2094 build time. On some systems (e.g. embedded ones), it is
2095 necessary or convenient to provide some or all of the
2096 kernel boot arguments with the kernel itself (that is,
2097 to not rely on the boot loader to provide them.)
2098
2099 To compile command line arguments into the kernel,
2100 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002101 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002102
2103 Systems with fully functional boot loaders (i.e. non-embedded)
2104 should leave this option set to 'N'.
2105
2106config CMDLINE
2107 string "Built-in kernel command string"
2108 depends on CMDLINE_BOOL
2109 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002110 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002111 Enter arguments here that should be compiled into the kernel
2112 image and used at boot time. If the boot loader provides a
2113 command line at boot time, it is appended to this string to
2114 form the full kernel command line, when the system boots.
2115
2116 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2117 change this behavior.
2118
2119 In most cases, the command line (whether built-in or provided
2120 by the boot loader) should specify the device for the root
2121 file system.
2122
2123config CMDLINE_OVERRIDE
2124 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002125 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002126 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002127 Set this option to 'Y' to have the kernel ignore the boot loader
2128 command line, and use ONLY the built-in command line.
2129
2130 This is used to work around broken boot loaders. This should
2131 be set to 'N' under normal conditions.
2132
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002133config MODIFY_LDT_SYSCALL
2134 bool "Enable the LDT (local descriptor table)" if EXPERT
2135 default y
2136 ---help---
2137 Linux can allow user programs to install a per-process x86
2138 Local Descriptor Table (LDT) using the modify_ldt(2) system
2139 call. This is required to run 16-bit or segmented code such as
2140 DOSEMU or some Wine programs. It is also used by some very old
2141 threading libraries.
2142
2143 Enabling this feature adds a small amount of overhead to
2144 context switches and increases the low-level kernel attack
2145 surface. Disabling it removes the modify_ldt(2) system call.
2146
2147 Saying 'N' here may make sense for embedded or server kernels.
2148
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002149source "kernel/livepatch/Kconfig"
2150
Sam Ravnborg506f1d02007-11-09 21:56:54 +01002151endmenu
2152
2153config ARCH_ENABLE_MEMORY_HOTPLUG
2154 def_bool y
2155 depends on X86_64 || (X86_32 && HIGHMEM)
2156
Gary Hade35551052008-10-31 10:52:03 -07002157config ARCH_ENABLE_MEMORY_HOTREMOVE
2158 def_bool y
2159 depends on MEMORY_HOTPLUG
2160
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002161config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002162 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002163 depends on NUMA
2164
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002165config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2166 def_bool y
2167 depends on X86_64 || X86_PAE
2168
Naoya Horiguchic177c812014-06-04 16:05:35 -07002169config ARCH_ENABLE_HUGEPAGE_MIGRATION
2170 def_bool y
2171 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2172
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002173menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002174
2175config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002176 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002177 depends on X86_64 && HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002178
2179source "kernel/power/Kconfig"
2180
2181source "drivers/acpi/Kconfig"
2182
Feng Tangefafc8b2009-08-14 15:23:29 -04002183source "drivers/sfi/Kconfig"
2184
Andi Kleena6b68072008-01-30 13:32:49 +01002185config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002186 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002187 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002188
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002189menuconfig APM
2190 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002191 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002192 ---help---
2193 APM is a BIOS specification for saving power using several different
2194 techniques. This is mostly useful for battery powered laptops with
2195 APM compliant BIOSes. If you say Y here, the system time will be
2196 reset after a RESUME operation, the /proc/apm device will provide
2197 battery status information, and user-space programs will receive
2198 notification of APM "events" (e.g. battery status change).
2199
2200 If you select "Y" here, you can disable actual use of the APM
2201 BIOS by passing the "apm=off" option to the kernel at boot time.
2202
2203 Note that the APM support is almost completely disabled for
2204 machines with more than one CPU.
2205
2206 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002207 and more information, read <file:Documentation/power/apm-acpi.txt>
2208 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002209 <http://www.tldp.org/docs.html#howto>.
2210
2211 This driver does not spin down disk drives (see the hdparm(8)
2212 manpage ("man 8 hdparm") for that), and it doesn't turn off
2213 VESA-compliant "green" monitors.
2214
2215 This driver does not support the TI 4000M TravelMate and the ACER
2216 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2217 desktop machines also don't have compliant BIOSes, and this driver
2218 may cause those machines to panic during the boot phase.
2219
2220 Generally, if you don't have a battery in your machine, there isn't
2221 much point in using this driver and you should say N. If you get
2222 random kernel OOPSes or reboots that don't seem to be related to
2223 anything, try disabling/enabling this option (or disabling/enabling
2224 APM in your BIOS).
2225
2226 Some other things you should try when experiencing seemingly random,
2227 "weird" problems:
2228
2229 1) make sure that you have enough swap space and that it is
2230 enabled.
2231 2) pass the "no-hlt" option to the kernel
2232 3) switch on floating point emulation in the kernel and pass
2233 the "no387" option to the kernel
2234 4) pass the "floppy=nodma" option to the kernel
2235 5) pass the "mem=4M" option to the kernel (thereby disabling
2236 all but the first 4 MB of RAM)
2237 6) make sure that the CPU is not over clocked.
2238 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2239 8) disable the cache from your BIOS settings
2240 9) install a fan for the video card or exchange video RAM
2241 10) install a better fan for the CPU
2242 11) exchange RAM chips
2243 12) exchange the motherboard.
2244
2245 To compile this driver as a module, choose M here: the
2246 module will be called apm.
2247
2248if APM
2249
2250config APM_IGNORE_USER_SUSPEND
2251 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002252 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002253 This option will ignore USER SUSPEND requests. On machines with a
2254 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2255 series notebooks, it is necessary to say Y because of a BIOS bug.
2256
2257config APM_DO_ENABLE
2258 bool "Enable PM at boot time"
2259 ---help---
2260 Enable APM features at boot time. From page 36 of the APM BIOS
2261 specification: "When disabled, the APM BIOS does not automatically
2262 power manage devices, enter the Standby State, enter the Suspend
2263 State, or take power saving steps in response to CPU Idle calls."
2264 This driver will make CPU Idle calls when Linux is idle (unless this
2265 feature is turned off -- see "Do CPU IDLE calls", below). This
2266 should always save battery power, but more complicated APM features
2267 will be dependent on your BIOS implementation. You may need to turn
2268 this option off if your computer hangs at boot time when using APM
2269 support, or if it beeps continuously instead of suspending. Turn
2270 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2271 T400CDT. This is off by default since most machines do fine without
2272 this feature.
2273
2274config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002275 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002276 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002277 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002278 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2279 On some machines, this can activate improved power savings, such as
2280 a slowed CPU clock rate, when the machine is idle. These idle calls
2281 are made after the idle loop has run for some length of time (e.g.,
2282 333 mS). On some machines, this will cause a hang at boot time or
2283 whenever the CPU becomes idle. (On machines with more than one CPU,
2284 this option does nothing.)
2285
2286config APM_DISPLAY_BLANK
2287 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002288 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002289 Enable console blanking using the APM. Some laptops can use this to
2290 turn off the LCD backlight when the screen blanker of the Linux
2291 virtual console blanks the screen. Note that this is only used by
2292 the virtual console screen blanker, and won't turn off the backlight
2293 when using the X Window system. This also doesn't have anything to
2294 do with your VESA-compliant power-saving monitor. Further, this
2295 option doesn't work for all laptops -- it might not turn off your
2296 backlight at all, or it might print a lot of errors to the console,
2297 especially if you are using gpm.
2298
2299config APM_ALLOW_INTS
2300 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002301 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002302 Normally we disable external interrupts while we are making calls to
2303 the APM BIOS as a measure to lessen the effects of a badly behaving
2304 BIOS implementation. The BIOS should reenable interrupts if it
2305 needs to. Unfortunately, some BIOSes do not -- especially those in
2306 many of the newer IBM Thinkpads. If you experience hangs when you
2307 suspend, try setting this to Y. Otherwise, say N.
2308
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002309endif # APM
2310
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002311source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002312
2313source "drivers/cpuidle/Kconfig"
2314
Andy Henroid27471fd2008-10-09 11:45:22 -07002315source "drivers/idle/Kconfig"
2316
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002317endmenu
2318
2319
2320menu "Bus options (PCI etc.)"
2321
2322config PCI
Ingo Molnar1ac97012008-05-19 14:10:14 +02002323 bool "PCI support"
Adrian Bunk1c858082008-01-30 13:32:32 +01002324 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002325 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002326 Find out whether you have a PCI motherboard. PCI is the name of a
2327 bus system, i.e. the way the CPU talks to the other stuff inside
2328 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2329 VESA. If you have PCI, say Y, otherwise N.
2330
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002331choice
2332 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002333 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002334 default PCI_GOANY
2335 ---help---
2336 On PCI systems, the BIOS can be used to detect the PCI devices and
2337 determine their configuration. However, some old PCI motherboards
2338 have BIOS bugs and may crash if this is done. Also, some embedded
2339 PCI-based systems don't have any BIOS at all. Linux can also try to
2340 detect the PCI hardware directly without using the BIOS.
2341
2342 With this option, you can specify how Linux should detect the
2343 PCI devices. If you choose "BIOS", the BIOS will be used,
2344 if you choose "Direct", the BIOS won't be used, and if you
2345 choose "MMConfig", then PCI Express MMCONFIG will be used.
2346 If you choose "Any", the kernel will try MMCONFIG, then the
2347 direct access method and falls back to the BIOS if that doesn't
2348 work. If unsure, go with the default, which is "Any".
2349
2350config PCI_GOBIOS
2351 bool "BIOS"
2352
2353config PCI_GOMMCONFIG
2354 bool "MMConfig"
2355
2356config PCI_GODIRECT
2357 bool "Direct"
2358
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002359config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002360 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002361 depends on OLPC
2362
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002363config PCI_GOANY
2364 bool "Any"
2365
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002366endchoice
2367
2368config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002369 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002370 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002371
2372# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2373config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002374 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002375 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002376
2377config PCI_MMCONFIG
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002378 def_bool y
Feng Tang5f0db7a2009-08-14 15:37:50 -04002379 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002380
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002381config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002382 def_bool y
2383 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002384
Alex Nixonb5401a92010-03-18 16:31:34 -04002385config PCI_XEN
2386 def_bool y
2387 depends on PCI && XEN
2388 select SWIOTLB_XEN
2389
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002390config PCI_DOMAINS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002391 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002392 depends on PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002393
2394config PCI_MMCONFIG
2395 bool "Support mmconfig PCI config space access"
2396 depends on X86_64 && PCI && ACPI
2397
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002398config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002399 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002400 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002401 help
2402 Read the PCI windows out of the CNB20LE host bridge. This allows
2403 PCI hotplug to work on systems with the CNB20LE chipset which do
2404 not have ACPI.
2405
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002406 There's no public spec for this chipset, and this functionality
2407 is known to be incomplete.
2408
2409 You should say N unless you know you need this.
2410
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002411source "drivers/pci/pcie/Kconfig"
2412
2413source "drivers/pci/Kconfig"
2414
David Rientjes1c00f012011-03-22 16:34:59 -07002415# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002416config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002417 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2418 default y
2419 help
2420 Enables ISA-style DMA support for devices requiring such controllers.
2421 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002422
2423if X86_32
2424
2425config ISA
2426 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002427 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002428 Find out whether you have ISA slots on your motherboard. ISA is the
2429 name of a bus system, i.e. the way the CPU talks to the other stuff
2430 inside your box. Other bus systems are PCI, EISA, MicroChannel
2431 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2432 newer boards don't support it. If you have ISA, say Y, otherwise N.
2433
2434config EISA
2435 bool "EISA support"
2436 depends on ISA
2437 ---help---
2438 The Extended Industry Standard Architecture (EISA) bus was
2439 developed as an open alternative to the IBM MicroChannel bus.
2440
2441 The EISA bus provided some of the features of the IBM MicroChannel
2442 bus while maintaining backward compatibility with cards made for
2443 the older ISA bus. The EISA bus saw limited use between 1988 and
2444 1995 when it was made obsolete by the PCI bus.
2445
2446 Say Y here if you are building a kernel for an EISA-based machine.
2447
2448 Otherwise, say N.
2449
2450source "drivers/eisa/Kconfig"
2451
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002452config SCx200
2453 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002454 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002455 This provides basic support for National Semiconductor's
2456 (now AMD's) Geode processors. The driver probes for the
2457 PCI-IDs of several on-chip devices, so its a good dependency
2458 for other scx200_* drivers.
2459
2460 If compiled as a module, the driver is named scx200.
2461
2462config SCx200HR_TIMER
2463 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002464 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002465 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002466 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002467 This driver provides a clocksource built upon the on-chip
2468 27MHz high-resolution timer. Its also a workaround for
2469 NSC Geode SC-1100's buggy TSC, which loses time when the
2470 processor goes idle (as is done by the scheduler). The
2471 other workaround is idle=poll boot option.
2472
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002473config OLPC
2474 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002475 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002476 select GPIOLIB
Thomas Gleixnerdc3119e72011-02-23 10:08:31 +01002477 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002478 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002479 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002480 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002481 Add support for detecting the unique features of the OLPC
2482 XO hardware.
2483
Daniel Drakea3128582011-06-25 17:34:10 +01002484config OLPC_XO1_PM
2485 bool "OLPC XO-1 Power Management"
Daniel Drake97c4cb72011-06-25 17:34:11 +01002486 depends on OLPC && MFD_CS5535 && PM_SLEEP
Daniel Drakea3128582011-06-25 17:34:10 +01002487 select MFD_CORE
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002488 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002489 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002490
Daniel Drakecfee9592011-06-25 17:34:17 +01002491config OLPC_XO1_RTC
2492 bool "OLPC XO-1 Real Time Clock"
2493 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2494 ---help---
2495 Add support for the XO-1 real time clock, which can be used as a
2496 programmable wakeup source.
2497
Daniel Drake7feda8e2011-06-25 17:34:12 +01002498config OLPC_XO1_SCI
2499 bool "OLPC XO-1 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002500 depends on OLPC && OLPC_XO1_PM
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002501 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002502 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002503 select GPIO_CS5535
2504 select MFD_CORE
2505 ---help---
2506 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002507 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002508 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002509 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002510 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002511 - AC adapter status updates
2512 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002513
Daniel Drakea0f30f52011-06-25 17:34:18 +01002514config OLPC_XO15_SCI
2515 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002516 depends on OLPC && ACPI
2517 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002518 ---help---
2519 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2520 - EC-driven system wakeups
2521 - AC adapter status updates
2522 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002523
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002524config ALIX
2525 bool "PCEngines ALIX System Support (LED setup)"
2526 select GPIOLIB
2527 ---help---
2528 This option enables system support for the PCEngines ALIX.
2529 At present this just sets up LEDs for GPIO control on
2530 ALIX2/3/6 boards. However, other system specific setup should
2531 get added here.
2532
2533 Note: You must still enable the drivers for GPIO and LED support
2534 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2535
2536 Note: You have to set alix.force=1 for boards with Award BIOS.
2537
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002538config NET5501
2539 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2540 select GPIOLIB
2541 ---help---
2542 This option enables system support for the Soekris Engineering net5501.
2543
Philip A. Prindeville31970592012-01-14 01:45:39 -07002544config GEOS
2545 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2546 select GPIOLIB
2547 depends on DMI
2548 ---help---
2549 This option enables system support for the Traverse Technologies GEOS.
2550
Vivien Didelot7d029122013-01-04 16:18:14 -05002551config TS5500
2552 bool "Technologic Systems TS-5500 platform support"
2553 depends on MELAN
2554 select CHECK_SIGNATURE
2555 select NEW_LEDS
2556 select LEDS_CLASS
2557 ---help---
2558 This option enables system support for the Technologic Systems TS-5500.
2559
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002560endif # X86_32
2561
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002562config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002563 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002564 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002565
2566source "drivers/pcmcia/Kconfig"
2567
2568source "drivers/pci/hotplug/Kconfig"
2569
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002570config RAPIDIO
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002571 tristate "RapidIO support"
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002572 depends on PCI
2573 default n
2574 help
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002575 If enabled this option will include drivers and the core
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002576 infrastructure code to support RapidIO interconnect devices.
2577
2578source "drivers/rapidio/Kconfig"
2579
David Herrmanne3263ab2013-08-02 14:05:22 +02002580config X86_SYSFB
2581 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2582 help
2583 Firmwares often provide initial graphics framebuffers so the BIOS,
2584 bootloader or kernel can show basic video-output during boot for
2585 user-guidance and debugging. Historically, x86 used the VESA BIOS
2586 Extensions and EFI-framebuffers for this, which are mostly limited
2587 to x86.
2588 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2589 framebuffers so the new generic system-framebuffer drivers can be
2590 used on x86. If the framebuffer is not compatible with the generic
2591 modes, it is adverticed as fallback platform framebuffer so legacy
2592 drivers like efifb, vesafb and uvesafb can pick it up.
2593 If this option is not selected, all system framebuffers are always
2594 marked as fallback platform framebuffers as usual.
2595
2596 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2597 not be able to pick up generic system framebuffers if this option
2598 is selected. You are highly encouraged to enable simplefb as
2599 replacement if you select this option. simplefb can correctly deal
2600 with generic system framebuffers. But you should still keep vesafb
2601 and others enabled as fallback if a system framebuffer is
2602 incompatible with simplefb.
2603
2604 If unsure, say Y.
2605
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002606endmenu
2607
2608
2609menu "Executable file formats / Emulations"
2610
2611source "fs/Kconfig.binfmt"
2612
2613config IA32_EMULATION
2614 bool "IA32 Emulation"
2615 depends on X86_64
Randy Dunlapd1603992013-06-18 12:33:40 -07002616 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002617 select COMPAT_BINFMT_ELF
Brian Gerst3bead552015-06-22 07:55:19 -04002618 select ARCH_WANT_OLD_COMPAT_IPC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002619 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002620 Include code to run legacy 32-bit programs under a
2621 64-bit kernel. You should likely turn this on, unless you're
2622 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002623
2624config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002625 tristate "IA32 a.out support"
2626 depends on IA32_EMULATION
2627 ---help---
2628 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002629
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002630config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002631 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002632 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002633 ---help---
2634 Include code to run binaries for the x32 native 32-bit ABI
2635 for 64-bit processors. An x32 process gets access to the
2636 full 64-bit register file and wide data path while leaving
2637 pointers at 32 bits for smaller memory footprint.
2638
2639 You will need a recent binutils (2.22 or later) with
2640 elf32_x86_64 support enabled to compile a kernel with this
2641 option set.
2642
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002643config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002644 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002645 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002646
Jan Beulich3120e252012-09-10 12:41:45 +01002647if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002648config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002649 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002650
2651config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002652 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002653 depends on SYSVIPC
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002654
David Howellsee009e4a02011-03-07 15:06:20 +00002655config KEYS_COMPAT
Jan Beulich3120e252012-09-10 12:41:45 +01002656 def_bool y
2657 depends on KEYS
2658endif
David Howellsee009e4a02011-03-07 15:06:20 +00002659
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002660endmenu
2661
2662
Keith Packarde5beae12008-11-03 18:21:45 +01002663config HAVE_ATOMIC_IOMAP
2664 def_bool y
2665 depends on X86_32
2666
Alessandro Rubini4692d772012-04-04 19:39:58 +02002667config X86_DEV_DMA_OPS
2668 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002669 depends on X86_64 || STA2X11
Alessandro Rubini4692d772012-04-04 19:39:58 +02002670
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002671config X86_DMA_REMAP
2672 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002673 depends on STA2X11
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002674
Li, Aubrey93e5ead2014-06-30 14:08:42 +08002675config PMC_ATOM
2676 def_bool y
2677 depends on PCI
2678
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002679source "net/Kconfig"
2680
2681source "drivers/Kconfig"
2682
2683source "drivers/firmware/Kconfig"
2684
2685source "fs/Kconfig"
2686
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002687source "arch/x86/Kconfig.debug"
2688
2689source "security/Kconfig"
2690
2691source "crypto/Kconfig"
2692
Avi Kivityedf88412007-12-16 11:02:48 +02002693source "arch/x86/kvm/Kconfig"
2694
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002695source "lib/Kconfig"