xref: /linux/arch/x86/Kconfig (revision 21266be9ed542f13436bd9c75316d43e1e84f6ae)
1daa93fabSSam Ravnborg# Select 32 or 64 bit
2daa93fabSSam Ravnborgconfig 64BIT
36840999bSSam Ravnborg	bool "64-bit kernel" if ARCH = "x86"
4ffee0de4SDavid Woodhouse	default ARCH != "i386"
58f9ca475SIngo Molnar	---help---
6daa93fabSSam Ravnborg	  Say yes to build a 64-bit kernel - formerly known as x86_64
7daa93fabSSam Ravnborg	  Say no to build a 32-bit kernel - formerly known as i386
8daa93fabSSam Ravnborg
9daa93fabSSam Ravnborgconfig X86_32
103120e25eSJan Beulich	def_bool y
113120e25eSJan Beulich	depends on !64BIT
12daa93fabSSam Ravnborg
13daa93fabSSam Ravnborgconfig X86_64
143120e25eSJan Beulich	def_bool y
153120e25eSJan Beulich	depends on 64BIT
161032c0baSSam Ravnborg
171032c0baSSam Ravnborg### Arch settings
188d5fffb9SSam Ravnborgconfig X86
193c2362e6SHarvey Harrison	def_bool y
206471b825SIngo Molnar	select ACPI_LEGACY_TABLES_LOOKUP	if ACPI
216e0a0ea1SGraeme Gregory	select ACPI_SYSTEM_POWER_STATES_SUPPORT	if ACPI
226471b825SIngo Molnar	select ANON_INODES
236471b825SIngo Molnar	select ARCH_CLOCKSOURCE_DATA
246471b825SIngo Molnar	select ARCH_DISCARD_MEMBLOCK
256471b825SIngo Molnar	select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
26446f24d1SStephen Boyd	select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
27*21266be9SDan Williams	select ARCH_HAS_DEVMEM_IS_ALLOWED
286471b825SIngo Molnar	select ARCH_HAS_ELF_RANDOMIZE
2972d93104SLinus Torvalds	select ARCH_HAS_FAST_MULTIPLIER
30957e3facSRiku Voipio	select ARCH_HAS_GCOV_PROFILE_ALL
3196601adbSDan Williams	select ARCH_HAS_PMEM_API		if X86_64
3267a3e8feSRoss Zwisler	select ARCH_HAS_MMIO_FLUSH
336471b825SIngo Molnar	select ARCH_HAS_SG_CHAIN
346471b825SIngo Molnar	select ARCH_HAVE_NMI_SAFE_CMPXCHG
356471b825SIngo Molnar	select ARCH_MIGHT_HAVE_ACPI_PDC		if ACPI
3677fbbc81SMark Salter	select ARCH_MIGHT_HAVE_PC_PARPORT
375e2c18c0SMark Salter	select ARCH_MIGHT_HAVE_PC_SERIO
386471b825SIngo Molnar	select ARCH_SUPPORTS_ATOMIC_RMW
393b242c66SMel Gorman	select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
40be5e610cSPeter Zijlstra	select ARCH_SUPPORTS_INT128		if X86_64
416471b825SIngo Molnar	select ARCH_SUPPORTS_NUMA_BALANCING	if X86_64
426471b825SIngo Molnar	select ARCH_USE_BUILTIN_BSWAP
436471b825SIngo Molnar	select ARCH_USE_CMPXCHG_LOCKREF		if X86_64
446471b825SIngo Molnar	select ARCH_USE_QUEUED_RWLOCKS
456471b825SIngo Molnar	select ARCH_USE_QUEUED_SPINLOCKS
4672b252aeSMel Gorman	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP
475aaeb5c0SIngo Molnar	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
48da4276b8SIngo Molnar	select ARCH_WANT_FRAME_POINTERS
496471b825SIngo Molnar	select ARCH_WANT_IPC_PARSE_VERSION	if X86_32
506471b825SIngo Molnar	select ARCH_WANT_OPTIONAL_GPIOLIB
516471b825SIngo Molnar	select BUILDTIME_EXTABLE_SORT
526471b825SIngo Molnar	select CLKEVT_I8253
536471b825SIngo Molnar	select CLKSRC_I8253			if X86_32
546471b825SIngo Molnar	select CLOCKSOURCE_VALIDATE_LAST_CYCLE
556471b825SIngo Molnar	select CLOCKSOURCE_WATCHDOG
566471b825SIngo Molnar	select CLONE_BACKWARDS			if X86_32
576471b825SIngo Molnar	select COMPAT_OLD_SIGACTION		if IA32_EMULATION
586471b825SIngo Molnar	select DCACHE_WORD_ACCESS
5945471cd9SLinus Torvalds	select EDAC_ATOMIC_SCRUB
6045471cd9SLinus Torvalds	select EDAC_SUPPORT
616471b825SIngo Molnar	select GENERIC_CLOCKEVENTS
626471b825SIngo Molnar	select GENERIC_CLOCKEVENTS_BROADCAST	if X86_64 || (X86_32 && X86_LOCAL_APIC)
636471b825SIngo Molnar	select GENERIC_CLOCKEVENTS_MIN_ADJUST
646471b825SIngo Molnar	select GENERIC_CMOS_UPDATE
656471b825SIngo Molnar	select GENERIC_CPU_AUTOPROBE
666471b825SIngo Molnar	select GENERIC_EARLY_IOREMAP
676471b825SIngo Molnar	select GENERIC_FIND_FIRST_BIT
686471b825SIngo Molnar	select GENERIC_IOMAP
696471b825SIngo Molnar	select GENERIC_IRQ_PROBE
706471b825SIngo Molnar	select GENERIC_IRQ_SHOW
716471b825SIngo Molnar	select GENERIC_PENDING_IRQ		if SMP
726471b825SIngo Molnar	select GENERIC_SMP_IDLE_THREAD
736471b825SIngo Molnar	select GENERIC_STRNCPY_FROM_USER
746471b825SIngo Molnar	select GENERIC_STRNLEN_USER
756471b825SIngo Molnar	select GENERIC_TIME_VSYSCALL
766471b825SIngo Molnar	select HAVE_ACPI_APEI			if ACPI
776471b825SIngo Molnar	select HAVE_ACPI_APEI_NMI		if ACPI
786471b825SIngo Molnar	select HAVE_ALIGNED_STRUCT_PAGE		if SLUB
796471b825SIngo Molnar	select HAVE_AOUT			if X86_32
806471b825SIngo Molnar	select HAVE_ARCH_AUDITSYSCALL
816471b825SIngo Molnar	select HAVE_ARCH_HUGE_VMAP		if X86_64 || X86_PAE
826471b825SIngo Molnar	select HAVE_ARCH_JUMP_LABEL
836471b825SIngo Molnar	select HAVE_ARCH_KASAN			if X86_64 && SPARSEMEM_VMEMMAP
846471b825SIngo Molnar	select HAVE_ARCH_KGDB
856471b825SIngo Molnar	select HAVE_ARCH_KMEMCHECK
866471b825SIngo Molnar	select HAVE_ARCH_SECCOMP_FILTER
876471b825SIngo Molnar	select HAVE_ARCH_SOFT_DIRTY		if X86_64
886471b825SIngo Molnar	select HAVE_ARCH_TRACEHOOK
896471b825SIngo Molnar	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
906471b825SIngo Molnar	select HAVE_BPF_JIT			if X86_64
916471b825SIngo Molnar	select HAVE_CC_STACKPROTECTOR
926471b825SIngo Molnar	select HAVE_CMPXCHG_DOUBLE
936471b825SIngo Molnar	select HAVE_CMPXCHG_LOCAL
946471b825SIngo Molnar	select HAVE_CONTEXT_TRACKING		if X86_64
95c1bd55f9SJosh Triplett	select HAVE_COPY_THREAD_TLS
966471b825SIngo Molnar	select HAVE_C_RECORDMCOUNT
976471b825SIngo Molnar	select HAVE_DEBUG_KMEMLEAK
986471b825SIngo Molnar	select HAVE_DEBUG_STACKOVERFLOW
996471b825SIngo Molnar	select HAVE_DMA_API_DEBUG
1007c095e46SFUJITA Tomonori	select HAVE_DMA_ATTRS
1019c5a3621SAkinobu Mita	select HAVE_DMA_CONTIGUOUS
102677aa9f7SSteven Rostedt	select HAVE_DYNAMIC_FTRACE
10306aeaaeaSMasami Hiramatsu	select HAVE_DYNAMIC_FTRACE_WITH_REGS
10458340a07SJohannes Berg	select HAVE_EFFICIENT_UNALIGNED_ACCESS
1056471b825SIngo Molnar	select HAVE_FENTRY			if X86_64
1066471b825SIngo Molnar	select HAVE_FTRACE_MCOUNT_RECORD
1076471b825SIngo Molnar	select HAVE_FUNCTION_GRAPH_FP_TEST
1086471b825SIngo Molnar	select HAVE_FUNCTION_GRAPH_TRACER
1096471b825SIngo Molnar	select HAVE_FUNCTION_TRACER
1106471b825SIngo Molnar	select HAVE_GENERIC_DMA_COHERENT	if X86_32
1110067f129SK.Prasad	select HAVE_HW_BREAKPOINT
1126471b825SIngo Molnar	select HAVE_IDE
1136471b825SIngo Molnar	select HAVE_IOREMAP_PROT
1146471b825SIngo Molnar	select HAVE_IRQ_EXIT_ON_IRQ_STACK	if X86_64
1156471b825SIngo Molnar	select HAVE_IRQ_TIME_ACCOUNTING
1166471b825SIngo Molnar	select HAVE_KERNEL_BZIP2
1176471b825SIngo Molnar	select HAVE_KERNEL_GZIP
1186471b825SIngo Molnar	select HAVE_KERNEL_LZ4
1196471b825SIngo Molnar	select HAVE_KERNEL_LZMA
1206471b825SIngo Molnar	select HAVE_KERNEL_LZO
1216471b825SIngo Molnar	select HAVE_KERNEL_XZ
1226471b825SIngo Molnar	select HAVE_KPROBES
1236471b825SIngo Molnar	select HAVE_KPROBES_ON_FTRACE
1246471b825SIngo Molnar	select HAVE_KRETPROBES
1256471b825SIngo Molnar	select HAVE_KVM
1266471b825SIngo Molnar	select HAVE_LIVEPATCH			if X86_64
1276471b825SIngo Molnar	select HAVE_MEMBLOCK
1286471b825SIngo Molnar	select HAVE_MEMBLOCK_NODE_MAP
1290102752eSFrederic Weisbecker	select HAVE_MIXED_BREAKPOINTS_REGS
1306471b825SIngo Molnar	select HAVE_OPROFILE
1316471b825SIngo Molnar	select HAVE_OPTPROBES
1326471b825SIngo Molnar	select HAVE_PCSPKR_PLATFORM
1336471b825SIngo Molnar	select HAVE_PERF_EVENTS
134c01d4323SFrederic Weisbecker	select HAVE_PERF_EVENTS_NMI
135c5e63197SJiri Olsa	select HAVE_PERF_REGS
136c5ebcedbSJiri Olsa	select HAVE_PERF_USER_STACK_DUMP
1376471b825SIngo Molnar	select HAVE_REGS_AND_STACK_ACCESS_API
1386471b825SIngo Molnar	select HAVE_SYSCALL_TRACEPOINTS
1390c3619eaSBrian Gerst	select HAVE_UID16			if X86_32 || IA32_EMULATION
1406471b825SIngo Molnar	select HAVE_UNSTABLE_SCHED_CLOCK
1417c68af6eSAvi Kivity	select HAVE_USER_RETURN_NOTIFIER
142c0185808SThomas Gleixner	select IRQ_FORCED_THREADING
143786d35d4SDavid Howells	select MODULES_USE_ELF_RELA		if X86_64
1446471b825SIngo Molnar	select MODULES_USE_ELF_REL		if X86_32
1455b3eb3adSAl Viro	select OLD_SIGACTION			if X86_32
1466471b825SIngo Molnar	select OLD_SIGSUSPEND3			if X86_32 || IA32_EMULATION
1476471b825SIngo Molnar	select PERF_EVENTS
1483195ef59SPrarit Bhargava	select RTC_LIB
1496471b825SIngo Molnar	select SPARSE_IRQ
15083fe27eaSPranith Kumar	select SRCU
1516471b825SIngo Molnar	select SYSCTL_EXCEPTION_TRACE
1526471b825SIngo Molnar	select USER_STACKTRACE_SUPPORT
1536471b825SIngo Molnar	select VIRT_TO_BUS
1546471b825SIngo Molnar	select X86_DEV_DMA_OPS			if X86_64
1556471b825SIngo Molnar	select X86_FEATURE_NAMES		if PROC_FS
1567d8330a5SBalbir Singh
157ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER
1583120e25eSJan Beulich	def_bool y
1593120e25eSJan Beulich	depends on KPROBES || PERF_EVENTS || UPROBES
160ba7e4d13SIngo Molnar
1617fb0f1deSPeter Zijlstraconfig PERF_EVENTS_INTEL_UNCORE
1627fb0f1deSPeter Zijlstra	def_bool y
163ce5686d4SPeter Zijlstra (Intel)	depends on PERF_EVENTS && CPU_SUP_INTEL && PCI
1647fb0f1deSPeter Zijlstra
16551b26adaSLinus Torvaldsconfig OUTPUT_FORMAT
16651b26adaSLinus Torvalds	string
16751b26adaSLinus Torvalds	default "elf32-i386" if X86_32
16851b26adaSLinus Torvalds	default "elf64-x86-64" if X86_64
16951b26adaSLinus Torvalds
17073531905SSam Ravnborgconfig ARCH_DEFCONFIG
171b9b39bfbSSam Ravnborg	string
17273531905SSam Ravnborg	default "arch/x86/configs/i386_defconfig" if X86_32
17373531905SSam Ravnborg	default "arch/x86/configs/x86_64_defconfig" if X86_64
174b9b39bfbSSam Ravnborg
1758d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT
1763c2362e6SHarvey Harrison	def_bool y
1778d5fffb9SSam Ravnborg
1788d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT
1793c2362e6SHarvey Harrison	def_bool y
1808d5fffb9SSam Ravnborg
181aa7d9350SHeiko Carstensconfig HAVE_LATENCYTOP_SUPPORT
182aa7d9350SHeiko Carstens	def_bool y
183aa7d9350SHeiko Carstens
1848d5fffb9SSam Ravnborgconfig MMU
1853c2362e6SHarvey Harrison	def_bool y
1868d5fffb9SSam Ravnborg
1878d5fffb9SSam Ravnborgconfig SBUS
1888d5fffb9SSam Ravnborg	bool
1898d5fffb9SSam Ravnborg
1903bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE
1913120e25eSJan Beulich	def_bool y
192a6dfa128SKonrad Rzeszutek Wilk	depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
1933bc4e459SFUJITA Tomonori
19418e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH
1954a14d84eSAndrew Morton	def_bool y
19618e98307SFUJITA Tomonori
1978d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA
1983120e25eSJan Beulich	def_bool y
1993120e25eSJan Beulich	depends on ISA_DMA_API
2008d5fffb9SSam Ravnborg
2018d5fffb9SSam Ravnborgconfig GENERIC_BUG
2023c2362e6SHarvey Harrison	def_bool y
2038d5fffb9SSam Ravnborg	depends on BUG
204b93a531eSJan Beulich	select GENERIC_BUG_RELATIVE_POINTERS if X86_64
205b93a531eSJan Beulich
206b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS
207b93a531eSJan Beulich	bool
2088d5fffb9SSam Ravnborg
2098d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT
2103c2362e6SHarvey Harrison	def_bool y
2118d5fffb9SSam Ravnborg
2128d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC
2133120e25eSJan Beulich	def_bool y
2143120e25eSJan Beulich	depends on ISA_DMA_API
2158d5fffb9SSam Ravnborg
2161032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM
2173120e25eSJan Beulich	def_bool y
2181032c0baSSam Ravnborg
2191032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY
2201032c0baSSam Ravnborg	def_bool y
2211032c0baSSam Ravnborg
2229a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX
2239a0b8415Svenkatesh.pallipadi@intel.com	def_bool y
2248d5fffb9SSam Ravnborg
2251b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE
2261b27d05bSPekka Enberg	def_bool y
2271b27d05bSPekka Enberg
228dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA
22989c9c4c5SBrian Gerst	def_bool y
230b32ef636Stravis@sgi.com
23108fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK
23208fc4580STejun Heo	def_bool y
23308fc4580STejun Heo
23408fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK
23511124411STejun Heo	def_bool y
23611124411STejun Heo
237801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE
238801e4062SJohannes Berg	def_bool y
239801e4062SJohannes Berg
240f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE
241f4cb5700SJohannes Berg	def_bool y
242f4cb5700SJohannes Berg
243cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE
244cfe28c5dSSteve Capper	def_bool y
245cfe28c5dSSteve Capper
24653313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB
24753313b2cSSteve Capper	def_bool y
24853313b2cSSteve Capper
2498d5fffb9SSam Ravnborgconfig ZONE_DMA32
250e0fd24a3SJan Beulich	def_bool y if X86_64
2518d5fffb9SSam Ravnborg
2528d5fffb9SSam Ravnborgconfig AUDIT_ARCH
253e0fd24a3SJan Beulich	def_bool y if X86_64
2548d5fffb9SSam Ravnborg
255765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING
256765c68bdSIngo Molnar	def_bool y
257765c68bdSIngo Molnar
2586a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC
2596a11f75bSAkinobu Mita	def_bool y
2606a11f75bSAkinobu Mita
261d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET
262d6f2d75aSAndrey Ryabinin	hex
263d6f2d75aSAndrey Ryabinin	depends on KASAN
264d6f2d75aSAndrey Ryabinin	default 0xdffffc0000000000
265d6f2d75aSAndrey Ryabinin
26669575d38SShane Wangconfig HAVE_INTEL_TXT
26769575d38SShane Wang	def_bool y
2686ea30386SKees Cook	depends on INTEL_IOMMU && ACPI
26969575d38SShane Wang
2706b0c3d44SSam Ravnborgconfig X86_32_SMP
2716b0c3d44SSam Ravnborg	def_bool y
2726b0c3d44SSam Ravnborg	depends on X86_32 && SMP
2736b0c3d44SSam Ravnborg
2746b0c3d44SSam Ravnborgconfig X86_64_SMP
2756b0c3d44SSam Ravnborg	def_bool y
2766b0c3d44SSam Ravnborg	depends on X86_64 && SMP
2776b0c3d44SSam Ravnborg
278ccbeed3aSTejun Heoconfig X86_32_LAZY_GS
279ccbeed3aSTejun Heo	def_bool y
28060a5317fSTejun Heo	depends on X86_32 && !CC_STACKPROTECTOR
281ccbeed3aSTejun Heo
282d61931d8SBorislav Petkovconfig ARCH_HWEIGHT_CFLAGS
283d61931d8SBorislav Petkov	string
284d61931d8SBorislav Petkov	default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
285d61931d8SBorislav Petkov	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
286d61931d8SBorislav Petkov
2872b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES
2882b144498SSrikar Dronamraju	def_bool y
2892b144498SSrikar Dronamraju
290d20642f0SRob Herringconfig FIX_EARLYCON_MEM
291d20642f0SRob Herring	def_bool y
292d20642f0SRob Herring
29398233368SKirill A. Shutemovconfig PGTABLE_LEVELS
29498233368SKirill A. Shutemov	int
29598233368SKirill A. Shutemov	default 4 if X86_64
29698233368SKirill A. Shutemov	default 3 if X86_PAE
29798233368SKirill A. Shutemov	default 2
29898233368SKirill A. Shutemov
299506f1d07SSam Ravnborgsource "init/Kconfig"
300dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer"
3018d5fffb9SSam Ravnborg
302506f1d07SSam Ravnborgmenu "Processor type and features"
303506f1d07SSam Ravnborg
3045ee71535SRandy Dunlapconfig ZONE_DMA
3055ee71535SRandy Dunlap	bool "DMA memory allocation support" if EXPERT
3065ee71535SRandy Dunlap	default y
3075ee71535SRandy Dunlap	help
3085ee71535SRandy Dunlap	  DMA memory allocation support allows devices with less than 32-bit
3095ee71535SRandy Dunlap	  addressing to allocate within the first 16MB of address space.
3105ee71535SRandy Dunlap	  Disable if no such devices will be used.
3115ee71535SRandy Dunlap
3125ee71535SRandy Dunlap	  If unsure, say Y.
3135ee71535SRandy Dunlap
314506f1d07SSam Ravnborgconfig SMP
315506f1d07SSam Ravnborg	bool "Symmetric multi-processing support"
316506f1d07SSam Ravnborg	---help---
317506f1d07SSam Ravnborg	  This enables support for systems with more than one CPU. If you have
3184a474157SRobert Graffham	  a system with only one CPU, say N. If you have a system with more
3194a474157SRobert Graffham	  than one CPU, say Y.
320506f1d07SSam Ravnborg
3214a474157SRobert Graffham	  If you say N here, the kernel will run on uni- and multiprocessor
322506f1d07SSam Ravnborg	  machines, but will use only one CPU of a multiprocessor machine. If
323506f1d07SSam Ravnborg	  you say Y here, the kernel will run on many, but not all,
3244a474157SRobert Graffham	  uniprocessor machines. On a uniprocessor machine, the kernel
325506f1d07SSam Ravnborg	  will run faster if you say N here.
326506f1d07SSam Ravnborg
327506f1d07SSam Ravnborg	  Note that if you say Y here and choose architecture "586" or
328506f1d07SSam Ravnborg	  "Pentium" under "Processor family", the kernel will not work on 486
329506f1d07SSam Ravnborg	  architectures. Similarly, multiprocessor kernels for the "PPro"
330506f1d07SSam Ravnborg	  architecture may not work on all Pentium based boards.
331506f1d07SSam Ravnborg
332506f1d07SSam Ravnborg	  People using multiprocessor machines who say Y here should also say
333506f1d07SSam Ravnborg	  Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
334506f1d07SSam Ravnborg	  Management" code will be disabled if you say Y here.
335506f1d07SSam Ravnborg
336395cf969SPaul Bolle	  See also <file:Documentation/x86/i386/IO-APIC.txt>,
337506f1d07SSam Ravnborg	  <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
338506f1d07SSam Ravnborg	  <http://www.tldp.org/docs.html#howto>.
339506f1d07SSam Ravnborg
340506f1d07SSam Ravnborg	  If you don't know what to do here, say N.
341506f1d07SSam Ravnborg
3429def39beSJosh Triplettconfig X86_FEATURE_NAMES
3439def39beSJosh Triplett	bool "Processor feature human-readable names" if EMBEDDED
3449def39beSJosh Triplett	default y
3459def39beSJosh Triplett	---help---
3469def39beSJosh Triplett	  This option compiles in a table of x86 feature bits and corresponding
3479def39beSJosh Triplett	  names.  This is required to support /proc/cpuinfo and a few kernel
3489def39beSJosh Triplett	  messages.  You can disable this to save space, at the expense of
3499def39beSJosh Triplett	  making those few kernel messages show numeric feature bits instead.
3509def39beSJosh Triplett
3519def39beSJosh Triplett	  If in doubt, say Y.
3529def39beSJosh Triplett
35306cd9a7dSYinghai Luconfig X86_X2APIC
35406cd9a7dSYinghai Lu	bool "Support x2apic"
35519e3d60dSJan Kiszka	depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
35606cd9a7dSYinghai Lu	---help---
35706cd9a7dSYinghai Lu	  This enables x2apic support on CPUs that have this feature.
35806cd9a7dSYinghai Lu
35906cd9a7dSYinghai Lu	  This allows 32-bit apic IDs (so it can support very large systems),
36006cd9a7dSYinghai Lu	  and accesses the local apic via MSRs not via mmio.
36106cd9a7dSYinghai Lu
36206cd9a7dSYinghai Lu	  If you don't know what to do here, say N.
36306cd9a7dSYinghai Lu
3646695c85bSYinghai Luconfig X86_MPPARSE
3656e87f9b7SBin Gao	bool "Enable MPS table" if ACPI || SFI
3667a527688SJan Beulich	default y
3675ab74722SIngo Molnar	depends on X86_LOCAL_APIC
3688f9ca475SIngo Molnar	---help---
3696695c85bSYinghai Lu	  For old smp systems that do not have proper acpi support. Newer systems
3706695c85bSYinghai Lu	  (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
3716695c85bSYinghai Lu
37226f7ef14SYinghai Luconfig X86_BIGSMP
37326f7ef14SYinghai Lu	bool "Support for big SMP systems with more than 8 CPUs"
37426f7ef14SYinghai Lu	depends on X86_32 && SMP
3758f9ca475SIngo Molnar	---help---
37626f7ef14SYinghai Lu	  This option is needed for the systems that have more than 8 CPUs
377506f1d07SSam Ravnborg
378ddd70cf9SJun Nakajimaconfig GOLDFISH
379ddd70cf9SJun Nakajima       def_bool y
380ddd70cf9SJun Nakajima       depends on X86_GOLDFISH
381ddd70cf9SJun Nakajima
3828425091fSRavikiran G Thirumalaiif X86_32
383c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM
384c5c606d9SRavikiran G Thirumalai	bool "Support for extended (non-PC) x86 platforms"
385c5c606d9SRavikiran G Thirumalai	default y
3868f9ca475SIngo Molnar	---help---
38706ac8346SIngo Molnar	  If you disable this option then the kernel will only support
38806ac8346SIngo Molnar	  standard PC platforms. (which covers the vast majority of
38906ac8346SIngo Molnar	  systems out there.)
39006ac8346SIngo Molnar
3918425091fSRavikiran G Thirumalai	  If you enable this option then you'll be able to select support
3928425091fSRavikiran G Thirumalai	  for the following (non-PC) 32 bit x86 platforms:
393cb7b8023SBen Hutchings		Goldfish (Android emulator)
3948425091fSRavikiran G Thirumalai		AMD Elan
3958425091fSRavikiran G Thirumalai		RDC R-321x SoC
3968425091fSRavikiran G Thirumalai		SGI 320/540 (Visual Workstation)
39783125a3aSAlessandro Rubini		STA2X11-based (e.g. Northville)
3983f4110a4SThomas Gleixner		Moorestown MID devices
39906ac8346SIngo Molnar
40006ac8346SIngo Molnar	  If you have one of these systems, or if you want to build a
40106ac8346SIngo Molnar	  generic distribution kernel, say Y here - otherwise say N.
4028425091fSRavikiran G Thirumalaiendif
40306ac8346SIngo Molnar
4048425091fSRavikiran G Thirumalaiif X86_64
4058425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM
4068425091fSRavikiran G Thirumalai	bool "Support for extended (non-PC) x86 platforms"
4078425091fSRavikiran G Thirumalai	default y
4088425091fSRavikiran G Thirumalai	---help---
4098425091fSRavikiran G Thirumalai	  If you disable this option then the kernel will only support
4108425091fSRavikiran G Thirumalai	  standard PC platforms. (which covers the vast majority of
4118425091fSRavikiran G Thirumalai	  systems out there.)
4128425091fSRavikiran G Thirumalai
4138425091fSRavikiran G Thirumalai	  If you enable this option then you'll be able to select support
4148425091fSRavikiran G Thirumalai	  for the following (non-PC) 64 bit x86 platforms:
41544b111b5SSteffen Persvold		Numascale NumaChip
4168425091fSRavikiran G Thirumalai		ScaleMP vSMP
4178425091fSRavikiran G Thirumalai		SGI Ultraviolet
4188425091fSRavikiran G Thirumalai
4198425091fSRavikiran G Thirumalai	  If you have one of these systems, or if you want to build a
4208425091fSRavikiran G Thirumalai	  generic distribution kernel, say Y here - otherwise say N.
4218425091fSRavikiran G Thirumalaiendif
422c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms
423c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions
42444b111b5SSteffen Persvoldconfig X86_NUMACHIP
42544b111b5SSteffen Persvold	bool "Numascale NumaChip"
42644b111b5SSteffen Persvold	depends on X86_64
42744b111b5SSteffen Persvold	depends on X86_EXTENDED_PLATFORM
42844b111b5SSteffen Persvold	depends on NUMA
42944b111b5SSteffen Persvold	depends on SMP
43044b111b5SSteffen Persvold	depends on X86_X2APIC
431f9726bfdSDaniel J Blueman	depends on PCI_MMCONFIG
43244b111b5SSteffen Persvold	---help---
43344b111b5SSteffen Persvold	  Adds support for Numascale NumaChip large-SMP systems. Needed to
43444b111b5SSteffen Persvold	  enable more than ~168 cores.
43544b111b5SSteffen Persvold	  If you don't have one of these, you should say N here.
43603b48632SNick Piggin
4376a48565eSIngo Molnarconfig X86_VSMP
438c5c606d9SRavikiran G Thirumalai	bool "ScaleMP vSMP"
4396276a074SBorislav Petkov	select HYPERVISOR_GUEST
4406a48565eSIngo Molnar	select PARAVIRT
4416a48565eSIngo Molnar	depends on X86_64 && PCI
442c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
443ead91d4bSShai Fultheim	depends on SMP
4448f9ca475SIngo Molnar	---help---
4456a48565eSIngo Molnar	  Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
4466a48565eSIngo Molnar	  supposed to run on these EM64T-based machines.  Only choose this option
4476a48565eSIngo Molnar	  if you have one of these machines.
4486a48565eSIngo Molnar
449c5c606d9SRavikiran G Thirumalaiconfig X86_UV
450c5c606d9SRavikiran G Thirumalai	bool "SGI Ultraviolet"
451c5c606d9SRavikiran G Thirumalai	depends on X86_64
452c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
45354c28d29SJack Steiner	depends on NUMA
4549d6c26e7SSuresh Siddha	depends on X86_X2APIC
4551222e564SIngo Molnar	depends on PCI
456c5c606d9SRavikiran G Thirumalai	---help---
457c5c606d9SRavikiran G Thirumalai	  This option is needed in order to support SGI Ultraviolet systems.
458c5c606d9SRavikiran G Thirumalai	  If you don't have one of these, you should say N here.
459c5c606d9SRavikiran G Thirumalai
460c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms
461c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions
462506f1d07SSam Ravnborg
463ddd70cf9SJun Nakajimaconfig X86_GOLDFISH
464ddd70cf9SJun Nakajima       bool "Goldfish (Virtual Platform)"
465cb7b8023SBen Hutchings       depends on X86_EXTENDED_PLATFORM
466ddd70cf9SJun Nakajima       ---help---
467ddd70cf9SJun Nakajima	 Enable support for the Goldfish virtual platform used primarily
468ddd70cf9SJun Nakajima	 for Android development. Unless you are building for the Android
469ddd70cf9SJun Nakajima	 Goldfish emulator say N here.
470ddd70cf9SJun Nakajima
471c751e17bSThomas Gleixnerconfig X86_INTEL_CE
472c751e17bSThomas Gleixner	bool "CE4100 TV platform"
473c751e17bSThomas Gleixner	depends on PCI
474c751e17bSThomas Gleixner	depends on PCI_GODIRECT
4756084a6e2SJiang Liu	depends on X86_IO_APIC
476c751e17bSThomas Gleixner	depends on X86_32
477c751e17bSThomas Gleixner	depends on X86_EXTENDED_PLATFORM
47837bc9f50SDirk Brandewie	select X86_REBOOTFIXUPS
479da6b737bSSebastian Andrzej Siewior	select OF
480da6b737bSSebastian Andrzej Siewior	select OF_EARLY_FLATTREE
481c751e17bSThomas Gleixner	---help---
482c751e17bSThomas Gleixner	  Select for the Intel CE media processor (CE4100) SOC.
483c751e17bSThomas Gleixner	  This option compiles in support for the CE4100 SOC for settop
484c751e17bSThomas Gleixner	  boxes and media devices.
485c751e17bSThomas Gleixner
4864cb9b00fSDavid Cohenconfig X86_INTEL_MID
48743605ef1SAlan Cox	bool "Intel MID platform support"
48843605ef1SAlan Cox	depends on X86_32
48943605ef1SAlan Cox	depends on X86_EXTENDED_PLATFORM
490edc6bc78SDavid Cohen	depends on X86_PLATFORM_DEVICES
4911ea7c673SAlan Cox	depends on PCI
4921ea7c673SAlan Cox	depends on PCI_GOANY
4931ea7c673SAlan Cox	depends on X86_IO_APIC
4947c9c3a1eSAlan Cox	select SFI
4954cb9b00fSDavid Cohen	select I2C
4967c9c3a1eSAlan Cox	select DW_APB_TIMER
4971ea7c673SAlan Cox	select APB_TIMER
4981ea7c673SAlan Cox	select INTEL_SCU_IPC
49915a713dfSMika Westerberg	select MFD_INTEL_MSIC
5001ea7c673SAlan Cox	---help---
5014cb9b00fSDavid Cohen	  Select to build a kernel capable of supporting Intel MID (Mobile
5024cb9b00fSDavid Cohen	  Internet Device) platform systems which do not have the PCI legacy
5034cb9b00fSDavid Cohen	  interfaces. If you are building for a PC class system say N here.
5041ea7c673SAlan Cox
5054cb9b00fSDavid Cohen	  Intel MID platforms are based on an Intel processor and chipset which
5064cb9b00fSDavid Cohen	  consume less power than most of the x86 derivatives.
50743605ef1SAlan Cox
5088bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK
5098bbc2a13SBryan O'Donoghue	bool "Intel Quark platform support"
5108bbc2a13SBryan O'Donoghue	depends on X86_32
5118bbc2a13SBryan O'Donoghue	depends on X86_EXTENDED_PLATFORM
5128bbc2a13SBryan O'Donoghue	depends on X86_PLATFORM_DEVICES
5138bbc2a13SBryan O'Donoghue	depends on X86_TSC
5148bbc2a13SBryan O'Donoghue	depends on PCI
5158bbc2a13SBryan O'Donoghue	depends on PCI_GOANY
5168bbc2a13SBryan O'Donoghue	depends on X86_IO_APIC
5178bbc2a13SBryan O'Donoghue	select IOSF_MBI
5188bbc2a13SBryan O'Donoghue	select INTEL_IMR
5199ab6eb51SAndy Shevchenko	select COMMON_CLK
5208bbc2a13SBryan O'Donoghue	---help---
5218bbc2a13SBryan O'Donoghue	  Select to include support for Quark X1000 SoC.
5228bbc2a13SBryan O'Donoghue	  Say Y here if you have a Quark based system such as the Arduino
5238bbc2a13SBryan O'Donoghue	  compatible Intel Galileo.
5248bbc2a13SBryan O'Donoghue
5253d48aab1SMika Westerbergconfig X86_INTEL_LPSS
5263d48aab1SMika Westerberg	bool "Intel Low Power Subsystem Support"
5273d48aab1SMika Westerberg	depends on ACPI
5283d48aab1SMika Westerberg	select COMMON_CLK
5290f531431SMathias Nyman	select PINCTRL
5303d48aab1SMika Westerberg	---help---
5313d48aab1SMika Westerberg	  Select to build support for Intel Low Power Subsystem such as
5323d48aab1SMika Westerberg	  found on Intel Lynxpoint PCH. Selecting this option enables
5330f531431SMathias Nyman	  things like clock tree (common clock framework) and pincontrol
5340f531431SMathias Nyman	  which are needed by the LPSS peripheral drivers.
5353d48aab1SMika Westerberg
53692082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE
53792082a88SKen Xue	bool "AMD ACPI2Platform devices support"
53892082a88SKen Xue	depends on ACPI
53992082a88SKen Xue	select COMMON_CLK
54092082a88SKen Xue	select PINCTRL
54192082a88SKen Xue	---help---
54292082a88SKen Xue	  Select to interpret AMD specific ACPI device to platform device
54392082a88SKen Xue	  such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
54492082a88SKen Xue	  I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
54592082a88SKen Xue	  implemented under PINCTRL subsystem.
54692082a88SKen Xue
547ced3ce76SDavid E. Boxconfig IOSF_MBI
548ced3ce76SDavid E. Box	tristate "Intel SoC IOSF Sideband support for SoC platforms"
549ced3ce76SDavid E. Box	depends on PCI
550ced3ce76SDavid E. Box	---help---
551ced3ce76SDavid E. Box	  This option enables sideband register access support for Intel SoC
552ced3ce76SDavid E. Box	  platforms. On these platforms the IOSF sideband is used in lieu of
553ced3ce76SDavid E. Box	  MSR's for some register accesses, mostly but not limited to thermal
554ced3ce76SDavid E. Box	  and power. Drivers may query the availability of this device to
555ced3ce76SDavid E. Box	  determine if they need the sideband in order to work on these
556ced3ce76SDavid E. Box	  platforms. The sideband is available on the following SoC products.
557ced3ce76SDavid E. Box	  This list is not meant to be exclusive.
558ced3ce76SDavid E. Box	   - BayTrail
559ced3ce76SDavid E. Box	   - Braswell
560ced3ce76SDavid E. Box	   - Quark
561ced3ce76SDavid E. Box
562ced3ce76SDavid E. Box	  You should say Y if you are running a kernel on one of these SoC's.
563ced3ce76SDavid E. Box
564ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG
565ed2226bdSDavid E. Box	bool "Enable IOSF sideband access through debugfs"
566ed2226bdSDavid E. Box	depends on IOSF_MBI && DEBUG_FS
567ed2226bdSDavid E. Box	---help---
568ed2226bdSDavid E. Box	  Select this option to expose the IOSF sideband access registers (MCR,
569ed2226bdSDavid E. Box	  MDR, MCRX) through debugfs to write and read register information from
570ed2226bdSDavid E. Box	  different units on the SoC. This is most useful for obtaining device
571ed2226bdSDavid E. Box	  state information for debug and analysis. As this is a general access
572ed2226bdSDavid E. Box	  mechanism, users of this option would have specific knowledge of the
573ed2226bdSDavid E. Box	  device they want to access.
574ed2226bdSDavid E. Box
575ed2226bdSDavid E. Box	  If you don't require the option or are in doubt, say N.
576ed2226bdSDavid E. Box
577c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X
578c5c606d9SRavikiran G Thirumalai	bool "RDC R-321x SoC"
579506f1d07SSam Ravnborg	depends on X86_32
580c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
581c5c606d9SRavikiran G Thirumalai	select M486
582c5c606d9SRavikiran G Thirumalai	select X86_REBOOTFIXUPS
583c5c606d9SRavikiran G Thirumalai	---help---
584c5c606d9SRavikiran G Thirumalai	  This option is needed for RDC R-321x system-on-chip, also known
585c5c606d9SRavikiran G Thirumalai	  as R-8610-(G).
586c5c606d9SRavikiran G Thirumalai	  If you don't have one of these chips, you should say N here.
587c5c606d9SRavikiran G Thirumalai
588e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD
5899c398017SIngo Molnar	bool "Support non-standard 32-bit SMP architectures"
5909c398017SIngo Molnar	depends on X86_32 && SMP
591c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
5928f9ca475SIngo Molnar	---help---
593b5660ba7SH. Peter Anvin	  This option compiles in the bigsmp and STA2X11 default
594b5660ba7SH. Peter Anvin	  subarchitectures.  It is intended for a generic binary
595b5660ba7SH. Peter Anvin	  kernel. If you select them all, kernel will probe it one by
596b5660ba7SH. Peter Anvin	  one and will fallback to default.
597d49c4288SYinghai Lu
598c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms
599d49c4288SYinghai Lu
600d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE
6016fc108a0SJan Beulich	def_bool y
602d949f36fSLinus Torvalds	# MCE code calls memory_failure():
603d949f36fSLinus Torvalds	depends on X86_MCE
604d949f36fSLinus Torvalds	# On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
605d949f36fSLinus Torvalds	# On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
606d949f36fSLinus Torvalds	depends on X86_64 || !SPARSEMEM
607d949f36fSLinus Torvalds	select ARCH_SUPPORTS_MEMORY_FAILURE
608d949f36fSLinus Torvalds
60983125a3aSAlessandro Rubiniconfig STA2X11
61083125a3aSAlessandro Rubini	bool "STA2X11 Companion Chip Support"
61183125a3aSAlessandro Rubini	depends on X86_32_NON_STANDARD && PCI
61283125a3aSAlessandro Rubini	select X86_DEV_DMA_OPS
61383125a3aSAlessandro Rubini	select X86_DMA_REMAP
61483125a3aSAlessandro Rubini	select SWIOTLB
61583125a3aSAlessandro Rubini	select MFD_STA2X11
61683125a3aSAlessandro Rubini	select ARCH_REQUIRE_GPIOLIB
61783125a3aSAlessandro Rubini	default n
61883125a3aSAlessandro Rubini	---help---
61983125a3aSAlessandro Rubini	  This adds support for boards based on the STA2X11 IO-Hub,
62083125a3aSAlessandro Rubini	  a.k.a. "ConneXt". The chip is used in place of the standard
62183125a3aSAlessandro Rubini	  PC chipset, so all "standard" peripherals are missing. If this
62283125a3aSAlessandro Rubini	  option is selected the kernel will still be able to boot on
62383125a3aSAlessandro Rubini	  standard PC machines.
62483125a3aSAlessandro Rubini
62582148d1dSShérabconfig X86_32_IRIS
62682148d1dSShérab	tristate "Eurobraille/Iris poweroff module"
62782148d1dSShérab	depends on X86_32
62882148d1dSShérab	---help---
62982148d1dSShérab	  The Iris machines from EuroBraille do not have APM or ACPI support
63082148d1dSShérab	  to shut themselves down properly.  A special I/O sequence is
63182148d1dSShérab	  needed to do so, which is what this module does at
63282148d1dSShérab	  kernel shutdown.
63382148d1dSShérab
63482148d1dSShérab	  This is only for Iris machines from EuroBraille.
63582148d1dSShérab
63682148d1dSShérab	  If unused, say N.
63782148d1dSShérab
638ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER
6393c2362e6SHarvey Harrison	def_bool y
6403c2362e6SHarvey Harrison	prompt "Single-depth WCHAN output"
641a87d0914SKen Chen	depends on X86
6428f9ca475SIngo Molnar	---help---
643506f1d07SSam Ravnborg	  Calculate simpler /proc/<PID>/wchan values. If this option
644506f1d07SSam Ravnborg	  is disabled then wchan values will recurse back to the
645506f1d07SSam Ravnborg	  caller function. This provides more accurate wchan values,
646506f1d07SSam Ravnborg	  at the expense of slightly more scheduling overhead.
647506f1d07SSam Ravnborg
648506f1d07SSam Ravnborg	  If in doubt, say "Y".
649506f1d07SSam Ravnborg
6506276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST
6516276a074SBorislav Petkov	bool "Linux guest support"
6528f9ca475SIngo Molnar	---help---
6536276a074SBorislav Petkov	  Say Y here to enable options for running Linux under various hyper-
6546276a074SBorislav Petkov	  visors. This option enables basic hypervisor detection and platform
6556276a074SBorislav Petkov	  setup.
656506f1d07SSam Ravnborg
6576276a074SBorislav Petkov	  If you say N, all options in this submenu will be skipped and
6586276a074SBorislav Petkov	  disabled, and Linux guest support won't be built in.
659506f1d07SSam Ravnborg
6606276a074SBorislav Petkovif HYPERVISOR_GUEST
661506f1d07SSam Ravnborg
662e61bd94aSEduardo Pereira Habkostconfig PARAVIRT
663e61bd94aSEduardo Pereira Habkost	bool "Enable paravirtualization code"
6648f9ca475SIngo Molnar	---help---
665e61bd94aSEduardo Pereira Habkost	  This changes the kernel so it can modify itself when it is run
666e61bd94aSEduardo Pereira Habkost	  under a hypervisor, potentially improving performance significantly
667e61bd94aSEduardo Pereira Habkost	  over full virtualization.  However, when run without a hypervisor
668e61bd94aSEduardo Pereira Habkost	  the kernel is theoretically slower and slightly larger.
669e61bd94aSEduardo Pereira Habkost
6706276a074SBorislav Petkovconfig PARAVIRT_DEBUG
6716276a074SBorislav Petkov	bool "paravirt-ops debugging"
6726276a074SBorislav Petkov	depends on PARAVIRT && DEBUG_KERNEL
6736276a074SBorislav Petkov	---help---
6746276a074SBorislav Petkov	  Enable to debug paravirt_ops internals.  Specifically, BUG if
6756276a074SBorislav Petkov	  a paravirt_op is missing when it is called.
6766276a074SBorislav Petkov
677b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS
678b4ecc126SJeremy Fitzhardinge	bool "Paravirtualization layer for spinlocks"
6796ea30386SKees Cook	depends on PARAVIRT && SMP
68062c7a1e9SIngo Molnar	select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS
681b4ecc126SJeremy Fitzhardinge	---help---
682b4ecc126SJeremy Fitzhardinge	  Paravirtualized spinlocks allow a pvops backend to replace the
683b4ecc126SJeremy Fitzhardinge	  spinlock implementation with something virtualization-friendly
684b4ecc126SJeremy Fitzhardinge	  (for example, block the virtual CPU rather than spinning).
685b4ecc126SJeremy Fitzhardinge
6864c4e4f61SRaghavendra K T	  It has a minimal impact on native kernels and gives a nice performance
6874c4e4f61SRaghavendra K T	  benefit on paravirtualized KVM / Xen kernels.
688b4ecc126SJeremy Fitzhardinge
6894c4e4f61SRaghavendra K T	  If you are unsure how to answer this question, answer Y.
690b4ecc126SJeremy Fitzhardinge
6916276a074SBorislav Petkovsource "arch/x86/xen/Kconfig"
6926276a074SBorislav Petkov
6936276a074SBorislav Petkovconfig KVM_GUEST
6946276a074SBorislav Petkov	bool "KVM Guest support (including kvmclock)"
6956276a074SBorislav Petkov	depends on PARAVIRT
6966276a074SBorislav Petkov	select PARAVIRT_CLOCK
6976276a074SBorislav Petkov	default y
6986276a074SBorislav Petkov	---help---
6996276a074SBorislav Petkov	  This option enables various optimizations for running under the KVM
7006276a074SBorislav Petkov	  hypervisor. It includes a paravirtualized clock, so that instead
7016276a074SBorislav Petkov	  of relying on a PIT (or probably other) emulation by the
7026276a074SBorislav Petkov	  underlying device model, the host provides the guest with
7036276a074SBorislav Petkov	  timing infrastructure such as time of day, and system time
7046276a074SBorislav Petkov
7051e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS
7061e20eb85SSrivatsa Vaddagiri	bool "Enable debug information for KVM Guests in debugfs"
7071e20eb85SSrivatsa Vaddagiri	depends on KVM_GUEST && DEBUG_FS
7081e20eb85SSrivatsa Vaddagiri	default n
7091e20eb85SSrivatsa Vaddagiri	---help---
7101e20eb85SSrivatsa Vaddagiri	  This option enables collection of various statistics for KVM guest.
7111e20eb85SSrivatsa Vaddagiri	  Statistics are displayed in debugfs filesystem. Enabling this option
7121e20eb85SSrivatsa Vaddagiri	  may incur significant overhead.
7131e20eb85SSrivatsa Vaddagiri
7146276a074SBorislav Petkovsource "arch/x86/lguest/Kconfig"
7156276a074SBorislav Petkov
7166276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING
7176276a074SBorislav Petkov	bool "Paravirtual steal time accounting"
7186276a074SBorislav Petkov	depends on PARAVIRT
7196276a074SBorislav Petkov	default n
7206276a074SBorislav Petkov	---help---
7216276a074SBorislav Petkov	  Select this option to enable fine granularity task steal time
7226276a074SBorislav Petkov	  accounting. Time spent executing other tasks in parallel with
7236276a074SBorislav Petkov	  the current vCPU is discounted from the vCPU power. To account for
7246276a074SBorislav Petkov	  that, there can be a small performance impact.
7256276a074SBorislav Petkov
7266276a074SBorislav Petkov	  If in doubt, say N here.
7276276a074SBorislav Petkov
7287af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK
7297af192c9SGerd Hoffmann	bool
7307af192c9SGerd Hoffmann
7316276a074SBorislav Petkovendif #HYPERVISOR_GUEST
73297349135SJeremy Fitzhardinge
73308677214SYinghai Luconfig NO_BOOTMEM
734774ea0bcSYinghai Lu	def_bool y
73508677214SYinghai Lu
736506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu"
737506f1d07SSam Ravnborg
738506f1d07SSam Ravnborgconfig HPET_TIMER
7393c2362e6SHarvey Harrison	def_bool X86_64
740506f1d07SSam Ravnborg	prompt "HPET Timer Support" if X86_32
7418f9ca475SIngo Molnar	---help---
742506f1d07SSam Ravnborg	  Use the IA-PC HPET (High Precision Event Timer) to manage
743506f1d07SSam Ravnborg	  time in preference to the PIT and RTC, if a HPET is
744506f1d07SSam Ravnborg	  present.
745506f1d07SSam Ravnborg	  HPET is the next generation timer replacing legacy 8254s.
746506f1d07SSam Ravnborg	  The HPET provides a stable time base on SMP
747506f1d07SSam Ravnborg	  systems, unlike the TSC, but it is more expensive to access,
748506f1d07SSam Ravnborg	  as it is off-chip.  You can find the HPET spec at
749e45f2c07SDenis V. Lunev	  <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
750506f1d07SSam Ravnborg
751506f1d07SSam Ravnborg	  You can safely choose Y here.  However, HPET will only be
752506f1d07SSam Ravnborg	  activated if the platform and the BIOS support this feature.
753506f1d07SSam Ravnborg	  Otherwise the 8254 will be used for timing services.
754506f1d07SSam Ravnborg
755506f1d07SSam Ravnborg	  Choose N to continue using the legacy 8254 timer.
756506f1d07SSam Ravnborg
757506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC
7583c2362e6SHarvey Harrison	def_bool y
7599d8af78bSBernhard Walle	depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
760506f1d07SSam Ravnborg
761bb24c471SJacob Panconfig APB_TIMER
762933b9463SAlan Cox       def_bool y if X86_INTEL_MID
763933b9463SAlan Cox       prompt "Intel MID APB Timer Support" if X86_INTEL_MID
76406c3df49SJamie Iles       select DW_APB_TIMER
765a0c3832aSAlan Cox       depends on X86_INTEL_MID && SFI
766bb24c471SJacob Pan       help
767bb24c471SJacob Pan         APB timer is the replacement for 8254, HPET on X86 MID platforms.
768bb24c471SJacob Pan         The APBT provides a stable time base on SMP
769bb24c471SJacob Pan         systems, unlike the TSC, but it is more expensive to access,
770bb24c471SJacob Pan         as it is off-chip. APB timers are always running regardless of CPU
771bb24c471SJacob Pan         C states, they are used as per CPU clockevent device when possible.
772bb24c471SJacob Pan
7736a108a14SDavid Rientjes# Mark as expert because too many people got it wrong.
774506f1d07SSam Ravnborg# The code disables itself when not needed.
7757ae9392cSThomas Petazzoniconfig DMI
7767ae9392cSThomas Petazzoni	default y
777cf074402SArd Biesheuvel	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
7786a108a14SDavid Rientjes	bool "Enable DMI scanning" if EXPERT
7798f9ca475SIngo Molnar	---help---
7807ae9392cSThomas Petazzoni	  Enabled scanning of DMI to identify machine quirks. Say Y
7817ae9392cSThomas Petazzoni	  here unless you have verified that your setup is not
7827ae9392cSThomas Petazzoni	  affected by entries in the DMI blacklist. Required by PNP
7837ae9392cSThomas Petazzoni	  BIOS code.
7847ae9392cSThomas Petazzoni
785506f1d07SSam Ravnborgconfig GART_IOMMU
78638901f1cSAndi Kleen	bool "Old AMD GART IOMMU support"
787506f1d07SSam Ravnborg	select SWIOTLB
78823ac4ae8SAndreas Herrmann	depends on X86_64 && PCI && AMD_NB
7898f9ca475SIngo Molnar	---help---
790ced3c42cSIngo Molnar	  Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
791ced3c42cSIngo Molnar	  GART based hardware IOMMUs.
792ced3c42cSIngo Molnar
793ced3c42cSIngo Molnar	  The GART supports full DMA access for devices with 32-bit access
794ced3c42cSIngo Molnar	  limitations, on systems with more than 3 GB. This is usually needed
795ced3c42cSIngo Molnar	  for USB, sound, many IDE/SATA chipsets and some other devices.
796ced3c42cSIngo Molnar
797ced3c42cSIngo Molnar	  Newer systems typically have a modern AMD IOMMU, supported via
798ced3c42cSIngo Molnar	  the CONFIG_AMD_IOMMU=y config option.
799ced3c42cSIngo Molnar
800ced3c42cSIngo Molnar	  In normal configurations this driver is only active when needed:
801ced3c42cSIngo Molnar	  there's more than 3 GB of memory and the system contains a
802ced3c42cSIngo Molnar	  32-bit limited device.
803ced3c42cSIngo Molnar
804ced3c42cSIngo Molnar	  If unsure, say Y.
805506f1d07SSam Ravnborg
806506f1d07SSam Ravnborgconfig CALGARY_IOMMU
807506f1d07SSam Ravnborg	bool "IBM Calgary IOMMU support"
808506f1d07SSam Ravnborg	select SWIOTLB
8096ea30386SKees Cook	depends on X86_64 && PCI
8108f9ca475SIngo Molnar	---help---
811506f1d07SSam Ravnborg	  Support for hardware IOMMUs in IBM's xSeries x366 and x460
812506f1d07SSam Ravnborg	  systems. Needed to run systems with more than 3GB of memory
813506f1d07SSam Ravnborg	  properly with 32-bit PCI devices that do not support DAC
814506f1d07SSam Ravnborg	  (Double Address Cycle). Calgary also supports bus level
815506f1d07SSam Ravnborg	  isolation, where all DMAs pass through the IOMMU.  This
816506f1d07SSam Ravnborg	  prevents them from going anywhere except their intended
817506f1d07SSam Ravnborg	  destination. This catches hard-to-find kernel bugs and
818506f1d07SSam Ravnborg	  mis-behaving drivers and devices that do not use the DMA-API
819506f1d07SSam Ravnborg	  properly to set up their DMA buffers.  The IOMMU can be
820506f1d07SSam Ravnborg	  turned off at boot time with the iommu=off parameter.
821506f1d07SSam Ravnborg	  Normally the kernel will make the right choice by itself.
822506f1d07SSam Ravnborg	  If unsure, say Y.
823506f1d07SSam Ravnborg
824506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT
8253c2362e6SHarvey Harrison	def_bool y
8263c2362e6SHarvey Harrison	prompt "Should Calgary be enabled by default?"
827506f1d07SSam Ravnborg	depends on CALGARY_IOMMU
8288f9ca475SIngo Molnar	---help---
829506f1d07SSam Ravnborg	  Should Calgary be enabled by default? if you choose 'y', Calgary
830506f1d07SSam Ravnborg	  will be used (if it exists). If you choose 'n', Calgary will not be
831506f1d07SSam Ravnborg	  used even if it exists. If you choose 'n' and would like to use
832506f1d07SSam Ravnborg	  Calgary anyway, pass 'iommu=calgary' on the kernel command line.
833506f1d07SSam Ravnborg	  If unsure, say Y.
834506f1d07SSam Ravnborg
835506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround
836506f1d07SSam Ravnborgconfig SWIOTLB
837a1afd01cSJoerg Roedel	def_bool y if X86_64
8388f9ca475SIngo Molnar	---help---
839506f1d07SSam Ravnborg	  Support for software bounce buffers used on x86-64 systems
8404454d327SJoe Millenbach	  which don't have a hardware IOMMU. Using this PCI devices
8414454d327SJoe Millenbach	  which can only access 32-bits of memory can be used on systems
8424454d327SJoe Millenbach	  with more than 3 GB of memory.
8434454d327SJoe Millenbach	  If unsure, say Y.
844506f1d07SSam Ravnborg
845a8522509SFUJITA Tomonoriconfig IOMMU_HELPER
8463120e25eSJan Beulich	def_bool y
8473120e25eSJan Beulich	depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
848d25e26b6SLinus Torvalds
8491184dc2fSMike Travisconfig MAXSMP
850ddb0c5a6SSamuel Thibault	bool "Enable Maximum number of SMP Processors and NUMA Nodes"
8516ea30386SKees Cook	depends on X86_64 && SMP && DEBUG_KERNEL
85236f5101aSMike Travis	select CPUMASK_OFFSTACK
8538f9ca475SIngo Molnar	---help---
854ddb0c5a6SSamuel Thibault	  Enable maximum number of CPUS and NUMA Nodes for this architecture.
8551184dc2fSMike Travis	  If unsure, say N.
856506f1d07SSam Ravnborg
857506f1d07SSam Ravnborgconfig NR_CPUS
85836f5101aSMike Travis	int "Maximum number of CPUs" if SMP && !MAXSMP
8592a3313f4SMichael K. Johnson	range 2 8 if SMP && X86_32 && !X86_BIGSMP
860bb61ccc7SJosh Boyer	range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
861b53b5edaSJosh Boyer	range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
86278637a97SMike Travis	default "1" if !SMP
863b53b5edaSJosh Boyer	default "8192" if MAXSMP
864b5660ba7SH. Peter Anvin	default "32" if SMP && X86_BIGSMP
865c5c19941SKirill A. Shutemov	default "8" if SMP && X86_32
866c5c19941SKirill A. Shutemov	default "64" if SMP
8678f9ca475SIngo Molnar	---help---
868506f1d07SSam Ravnborg	  This allows you to specify the maximum number of CPUs which this
869bb61ccc7SJosh Boyer	  kernel will support.  If CPUMASK_OFFSTACK is enabled, the maximum
870cad14bb9SKirill A. Shutemov	  supported value is 8192, otherwise the maximum value is 512.  The
871506f1d07SSam Ravnborg	  minimum value which makes sense is 2.
872506f1d07SSam Ravnborg
873506f1d07SSam Ravnborg	  This is purely to save memory - each supported CPU adds
874506f1d07SSam Ravnborg	  approximately eight kilobytes to the kernel image.
875506f1d07SSam Ravnborg
876506f1d07SSam Ravnborgconfig SCHED_SMT
877506f1d07SSam Ravnborg	bool "SMT (Hyperthreading) scheduler support"
878c8e56d20SBorislav Petkov	depends on SMP
8798f9ca475SIngo Molnar	---help---
880506f1d07SSam Ravnborg	  SMT scheduler support improves the CPU scheduler's decision making
881506f1d07SSam Ravnborg	  when dealing with Intel Pentium 4 chips with HyperThreading at a
882506f1d07SSam Ravnborg	  cost of slightly increased overhead in some places. If unsure say
883506f1d07SSam Ravnborg	  N here.
884506f1d07SSam Ravnborg
885506f1d07SSam Ravnborgconfig SCHED_MC
8863c2362e6SHarvey Harrison	def_bool y
8873c2362e6SHarvey Harrison	prompt "Multi-core scheduler support"
888c8e56d20SBorislav Petkov	depends on SMP
8898f9ca475SIngo Molnar	---help---
890506f1d07SSam Ravnborg	  Multi-core scheduler support improves the CPU scheduler's decision
891506f1d07SSam Ravnborg	  making when dealing with multi-core CPU chips at a cost of slightly
892506f1d07SSam Ravnborg	  increased overhead in some places. If unsure say N here.
893506f1d07SSam Ravnborg
894506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt"
895506f1d07SSam Ravnborg
89630b8b006SThomas Gleixnerconfig UP_LATE_INIT
89730b8b006SThomas Gleixner       def_bool y
898ba360f88SThomas Gleixner       depends on !SMP && X86_LOCAL_APIC
89930b8b006SThomas Gleixner
900506f1d07SSam Ravnborgconfig X86_UP_APIC
90150849eefSJan Beulich	bool "Local APIC support on uniprocessors" if !PCI_MSI
90250849eefSJan Beulich	default PCI_MSI
90338a1dfdaSBryan O'Donoghue	depends on X86_32 && !SMP && !X86_32_NON_STANDARD
9048f9ca475SIngo Molnar	---help---
905506f1d07SSam Ravnborg	  A local APIC (Advanced Programmable Interrupt Controller) is an
906506f1d07SSam Ravnborg	  integrated interrupt controller in the CPU. If you have a single-CPU
907506f1d07SSam Ravnborg	  system which has a processor with a local APIC, you can say Y here to
908506f1d07SSam Ravnborg	  enable and use it. If you say Y here even though your machine doesn't
909506f1d07SSam Ravnborg	  have a local APIC, then the kernel will still run with no slowdown at
910506f1d07SSam Ravnborg	  all. The local APIC supports CPU-generated self-interrupts (timer,
911506f1d07SSam Ravnborg	  performance counters), and the NMI watchdog which detects hard
912506f1d07SSam Ravnborg	  lockups.
913506f1d07SSam Ravnborg
914506f1d07SSam Ravnborgconfig X86_UP_IOAPIC
915506f1d07SSam Ravnborg	bool "IO-APIC support on uniprocessors"
916506f1d07SSam Ravnborg	depends on X86_UP_APIC
9178f9ca475SIngo Molnar	---help---
918506f1d07SSam Ravnborg	  An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
919506f1d07SSam Ravnborg	  SMP-capable replacement for PC-style interrupt controllers. Most
920506f1d07SSam Ravnborg	  SMP systems and many recent uniprocessor systems have one.
921506f1d07SSam Ravnborg
922506f1d07SSam Ravnborg	  If you have a single-CPU system with an IO-APIC, you can say Y here
923506f1d07SSam Ravnborg	  to use it. If you say Y here even though your machine doesn't have
924506f1d07SSam Ravnborg	  an IO-APIC, then the kernel will still run with no slowdown at all.
925506f1d07SSam Ravnborg
926506f1d07SSam Ravnborgconfig X86_LOCAL_APIC
9273c2362e6SHarvey Harrison	def_bool y
9280dbc6078SThomas Petazzoni	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
929b5dc8e6cSJiang Liu	select IRQ_DOMAIN_HIERARCHY
93052f518a3SJiang Liu	select PCI_MSI_IRQ_DOMAIN if PCI_MSI
931506f1d07SSam Ravnborg
932506f1d07SSam Ravnborgconfig X86_IO_APIC
933b1da1e71SJan Beulich	def_bool y
934b1da1e71SJan Beulich	depends on X86_LOCAL_APIC || X86_UP_IOAPIC
935506f1d07SSam Ravnborg
93641b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS
93741b9eb26SStefan Assmann	bool "Reroute for broken boot IRQs"
93841b9eb26SStefan Assmann	depends on X86_IO_APIC
9398f9ca475SIngo Molnar	---help---
94041b9eb26SStefan Assmann	  This option enables a workaround that fixes a source of
94141b9eb26SStefan Assmann	  spurious interrupts. This is recommended when threaded
94241b9eb26SStefan Assmann	  interrupt handling is used on systems where the generation of
94341b9eb26SStefan Assmann	  superfluous "boot interrupts" cannot be disabled.
94441b9eb26SStefan Assmann
94541b9eb26SStefan Assmann	  Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
94641b9eb26SStefan Assmann	  entry in the chipset's IO-APIC is masked (as, e.g. the RT
94741b9eb26SStefan Assmann	  kernel does during interrupt handling). On chipsets where this
94841b9eb26SStefan Assmann	  boot IRQ generation cannot be disabled, this workaround keeps
94941b9eb26SStefan Assmann	  the original IRQ line masked so that only the equivalent "boot
95041b9eb26SStefan Assmann	  IRQ" is delivered to the CPUs. The workaround also tells the
95141b9eb26SStefan Assmann	  kernel to set up the IRQ handler on the boot IRQ line. In this
95241b9eb26SStefan Assmann	  way only one interrupt is delivered to the kernel. Otherwise
95341b9eb26SStefan Assmann	  the spurious second interrupt may cause the kernel to bring
95441b9eb26SStefan Assmann	  down (vital) interrupt lines.
95541b9eb26SStefan Assmann
95641b9eb26SStefan Assmann	  Only affects "broken" chipsets. Interrupt sharing may be
95741b9eb26SStefan Assmann	  increased on these systems.
95841b9eb26SStefan Assmann
959506f1d07SSam Ravnborgconfig X86_MCE
960bab9bc65SAndi Kleen	bool "Machine Check / overheating reporting"
961648ed940SChen, Gong	select GENERIC_ALLOCATOR
962e57dbaf7SBorislav Petkov	default y
963506f1d07SSam Ravnborg	---help---
964bab9bc65SAndi Kleen	  Machine Check support allows the processor to notify the
965bab9bc65SAndi Kleen	  kernel if it detects a problem (e.g. overheating, data corruption).
966506f1d07SSam Ravnborg	  The action the kernel takes depends on the severity of the problem,
967bab9bc65SAndi Kleen	  ranging from warning messages to halting the machine.
9684efc0670SAndi Kleen
969506f1d07SSam Ravnborgconfig X86_MCE_INTEL
9703c2362e6SHarvey Harrison	def_bool y
9713c2362e6SHarvey Harrison	prompt "Intel MCE features"
972c1ebf835SAndi Kleen	depends on X86_MCE && X86_LOCAL_APIC
9738f9ca475SIngo Molnar	---help---
974506f1d07SSam Ravnborg	   Additional support for intel specific MCE features such as
975506f1d07SSam Ravnborg	   the thermal monitor.
976506f1d07SSam Ravnborg
977506f1d07SSam Ravnborgconfig X86_MCE_AMD
9783c2362e6SHarvey Harrison	def_bool y
9793c2362e6SHarvey Harrison	prompt "AMD MCE features"
980c1ebf835SAndi Kleen	depends on X86_MCE && X86_LOCAL_APIC
9818f9ca475SIngo Molnar	---help---
982506f1d07SSam Ravnborg	   Additional support for AMD specific MCE features such as
983506f1d07SSam Ravnborg	   the DRAM Error Threshold.
984506f1d07SSam Ravnborg
9854efc0670SAndi Kleenconfig X86_ANCIENT_MCE
9866fc108a0SJan Beulich	bool "Support for old Pentium 5 / WinChip machine checks"
987c31d9633SAndi Kleen	depends on X86_32 && X86_MCE
9884efc0670SAndi Kleen	---help---
9894efc0670SAndi Kleen	  Include support for machine check handling on old Pentium 5 or WinChip
9905065a706SMasanari Iida	  systems. These typically need to be enabled explicitly on the command
9914efc0670SAndi Kleen	  line.
9924efc0670SAndi Kleen
993b2762686SAndi Kleenconfig X86_MCE_THRESHOLD
994b2762686SAndi Kleen	depends on X86_MCE_AMD || X86_MCE_INTEL
9956fc108a0SJan Beulich	def_bool y
996b2762686SAndi Kleen
997ea149b36SAndi Kleenconfig X86_MCE_INJECT
998c1ebf835SAndi Kleen	depends on X86_MCE
999ea149b36SAndi Kleen	tristate "Machine check injector support"
1000ea149b36SAndi Kleen	---help---
1001ea149b36SAndi Kleen	  Provide support for injecting machine checks for testing purposes.
1002ea149b36SAndi Kleen	  If you don't know what a machine check is and you don't do kernel
1003ea149b36SAndi Kleen	  QA it is safe to say n.
1004ea149b36SAndi Kleen
10054efc0670SAndi Kleenconfig X86_THERMAL_VECTOR
10064efc0670SAndi Kleen	def_bool y
10075bb38adcSAndi Kleen	depends on X86_MCE_INTEL
10084efc0670SAndi Kleen
10095aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86
10101e642812SIngo Molnar	bool "Legacy VM86 support"
10115aef51c3SAndy Lutomirski	default n
1012506f1d07SSam Ravnborg	depends on X86_32
10138f9ca475SIngo Molnar	---help---
10145aef51c3SAndy Lutomirski	  This option allows user programs to put the CPU into V8086
10155aef51c3SAndy Lutomirski	  mode, which is an 80286-era approximation of 16-bit real mode.
10165aef51c3SAndy Lutomirski
10175aef51c3SAndy Lutomirski	  Some very old versions of X and/or vbetool require this option
10185aef51c3SAndy Lutomirski	  for user mode setting.  Similarly, DOSEMU will use it if
10195aef51c3SAndy Lutomirski	  available to accelerate real mode DOS programs.  However, any
10205aef51c3SAndy Lutomirski	  recent version of DOSEMU, X, or vbetool should be fully
10215aef51c3SAndy Lutomirski	  functional even without kernel VM86 support, as they will all
10221e642812SIngo Molnar	  fall back to software emulation. Nevertheless, if you are using
10231e642812SIngo Molnar	  a 16-bit DOS program where 16-bit performance matters, vm86
10241e642812SIngo Molnar	  mode might be faster than emulation and you might want to
10251e642812SIngo Molnar	  enable this option.
10265aef51c3SAndy Lutomirski
10271e642812SIngo Molnar	  Note that any app that works on a 64-bit kernel is unlikely to
10281e642812SIngo Molnar	  need this option, as 64-bit kernels don't, and can't, support
10291e642812SIngo Molnar	  V8086 mode. This option is also unrelated to 16-bit protected
10301e642812SIngo Molnar	  mode and is not needed to run most 16-bit programs under Wine.
10315aef51c3SAndy Lutomirski
10321e642812SIngo Molnar	  Enabling this option increases the complexity of the kernel
10331e642812SIngo Molnar	  and slows down exception handling a tiny bit.
10345aef51c3SAndy Lutomirski
10351e642812SIngo Molnar	  If unsure, say N here.
10365aef51c3SAndy Lutomirski
10375aef51c3SAndy Lutomirskiconfig VM86
10385aef51c3SAndy Lutomirski       bool
10395aef51c3SAndy Lutomirski       default X86_LEGACY_VM86
104034273f41SH. Peter Anvin
104134273f41SH. Peter Anvinconfig X86_16BIT
104234273f41SH. Peter Anvin	bool "Enable support for 16-bit segments" if EXPERT
104334273f41SH. Peter Anvin	default y
1044a5b9e5a2SAndy Lutomirski	depends on MODIFY_LDT_SYSCALL
104534273f41SH. Peter Anvin	---help---
104634273f41SH. Peter Anvin	  This option is required by programs like Wine to run 16-bit
104734273f41SH. Peter Anvin	  protected mode legacy code on x86 processors.  Disabling
104834273f41SH. Peter Anvin	  this option saves about 300 bytes on i386, or around 6K text
104934273f41SH. Peter Anvin	  plus 16K runtime memory on x86-64,
105034273f41SH. Peter Anvin
105134273f41SH. Peter Anvinconfig X86_ESPFIX32
105234273f41SH. Peter Anvin	def_bool y
105334273f41SH. Peter Anvin	depends on X86_16BIT && X86_32
1054506f1d07SSam Ravnborg
1055197725deSH. Peter Anvinconfig X86_ESPFIX64
1056197725deSH. Peter Anvin	def_bool y
105734273f41SH. Peter Anvin	depends on X86_16BIT && X86_64
1058506f1d07SSam Ravnborg
10591ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION
10601ad83c85SAndy Lutomirski       bool "Enable vsyscall emulation" if EXPERT
10611ad83c85SAndy Lutomirski       default y
10621ad83c85SAndy Lutomirski       depends on X86_64
10631ad83c85SAndy Lutomirski       ---help---
10641ad83c85SAndy Lutomirski	 This enables emulation of the legacy vsyscall page.  Disabling
10651ad83c85SAndy Lutomirski	 it is roughly equivalent to booting with vsyscall=none, except
10661ad83c85SAndy Lutomirski	 that it will also disable the helpful warning if a program
10671ad83c85SAndy Lutomirski	 tries to use a vsyscall.  With this option set to N, offending
10681ad83c85SAndy Lutomirski	 programs will just segfault, citing addresses of the form
10691ad83c85SAndy Lutomirski	 0xffffffffff600?00.
10701ad83c85SAndy Lutomirski
10711ad83c85SAndy Lutomirski	 This option is required by many programs built before 2013, and
10721ad83c85SAndy Lutomirski	 care should be used even with newer programs if set to N.
10731ad83c85SAndy Lutomirski
10741ad83c85SAndy Lutomirski	 Disabling this option saves about 7K of kernel size and
10751ad83c85SAndy Lutomirski	 possibly 4K of additional runtime pagetable memory.
10761ad83c85SAndy Lutomirski
1077506f1d07SSam Ravnborgconfig TOSHIBA
1078506f1d07SSam Ravnborg	tristate "Toshiba Laptop support"
1079506f1d07SSam Ravnborg	depends on X86_32
1080506f1d07SSam Ravnborg	---help---
1081506f1d07SSam Ravnborg	  This adds a driver to safely access the System Management Mode of
1082506f1d07SSam Ravnborg	  the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1083506f1d07SSam Ravnborg	  not work on models with a Phoenix BIOS. The System Management Mode
1084506f1d07SSam Ravnborg	  is used to set the BIOS and power saving options on Toshiba portables.
1085506f1d07SSam Ravnborg
1086506f1d07SSam Ravnborg	  For information on utilities to make use of this driver see the
1087506f1d07SSam Ravnborg	  Toshiba Linux utilities web site at:
1088506f1d07SSam Ravnborg	  <http://www.buzzard.org.uk/toshiba/>.
1089506f1d07SSam Ravnborg
1090506f1d07SSam Ravnborg	  Say Y if you intend to run this kernel on a Toshiba portable.
1091506f1d07SSam Ravnborg	  Say N otherwise.
1092506f1d07SSam Ravnborg
1093506f1d07SSam Ravnborgconfig I8K
1094039ae585SPali Rohár	tristate "Dell i8k legacy laptop support"
1095949a9d70SJean Delvare	select HWMON
1096039ae585SPali Rohár	select SENSORS_DELL_SMM
1097506f1d07SSam Ravnborg	---help---
1098039ae585SPali Rohár	  This option enables legacy /proc/i8k userspace interface in hwmon
1099039ae585SPali Rohár	  dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1100039ae585SPali Rohár	  temperature and allows controlling fan speeds of Dell laptops via
1101039ae585SPali Rohár	  System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1102039ae585SPali Rohár	  it reports also power and hotkey status. For fan speed control is
1103039ae585SPali Rohár	  needed userspace package i8kutils.
1104506f1d07SSam Ravnborg
1105039ae585SPali Rohár	  Say Y if you intend to run this kernel on old Dell laptops or want to
1106039ae585SPali Rohár	  use userspace package i8kutils.
1107506f1d07SSam Ravnborg	  Say N otherwise.
1108506f1d07SSam Ravnborg
1109506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS
11109ba16087SJan Beulich	bool "Enable X86 board specific fixups for reboot"
11119ba16087SJan Beulich	depends on X86_32
1112506f1d07SSam Ravnborg	---help---
1113506f1d07SSam Ravnborg	  This enables chipset and/or board specific fixups to be done
1114506f1d07SSam Ravnborg	  in order to get reboot to work correctly. This is only needed on
1115506f1d07SSam Ravnborg	  some combinations of hardware and BIOS. The symptom, for which
1116506f1d07SSam Ravnborg	  this config is intended, is when reboot ends with a stalled/hung
1117506f1d07SSam Ravnborg	  system.
1118506f1d07SSam Ravnborg
1119506f1d07SSam Ravnborg	  Currently, the only fixup is for the Geode machines using
11205e3a77e9SFlorian Fainelli	  CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1121506f1d07SSam Ravnborg
1122506f1d07SSam Ravnborg	  Say Y if you want to enable the fixup. Currently, it's safe to
1123506f1d07SSam Ravnborg	  enable this option even if you don't need it.
1124506f1d07SSam Ravnborg	  Say N otherwise.
1125506f1d07SSam Ravnborg
1126506f1d07SSam Ravnborgconfig MICROCODE
11279a2bc335SBorislav Petkov	bool "CPU microcode loading support"
11289a2bc335SBorislav Petkov	default y
112980030e3dSBorislav Petkov	depends on CPU_SUP_AMD || CPU_SUP_INTEL
1130fe055896SBorislav Petkov	depends on BLK_DEV_INITRD
1131506f1d07SSam Ravnborg	select FW_LOADER
1132506f1d07SSam Ravnborg	---help---
1133e43f6e67SBorislav Petkov
1134506f1d07SSam Ravnborg	  If you say Y here, you will be able to update the microcode on
113580cc9f10SPeter Oruba	  certain Intel and AMD processors. The Intel support is for the
1136e43f6e67SBorislav Petkov	  IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1137e43f6e67SBorislav Petkov	  Xeon etc. The AMD support is for families 0x10 and later. You will
1138e43f6e67SBorislav Petkov	  obviously need the actual microcode binary data itself which is not
1139e43f6e67SBorislav Petkov	  shipped with the Linux kernel.
1140506f1d07SSam Ravnborg
11418d86f390SPeter Oruba	  This option selects the general module only, you need to select
11428d86f390SPeter Oruba	  at least one vendor specific module as well.
1143506f1d07SSam Ravnborg
1144e43f6e67SBorislav Petkov	  To compile this driver as a module, choose M here: the module
1145e43f6e67SBorislav Petkov	  will be called microcode.
1146506f1d07SSam Ravnborg
11478d86f390SPeter Orubaconfig MICROCODE_INTEL
1148e43f6e67SBorislav Petkov	bool "Intel microcode loading support"
11498d86f390SPeter Oruba	depends on MICROCODE
11508d86f390SPeter Oruba	default MICROCODE
11518d86f390SPeter Oruba	select FW_LOADER
11528f9ca475SIngo Molnar	---help---
11538d86f390SPeter Oruba	  This options enables microcode patch loading support for Intel
11548d86f390SPeter Oruba	  processors.
11558d86f390SPeter Oruba
1156b8989db9SAlan	  For the current Intel microcode data package go to
1157b8989db9SAlan	  <https://downloadcenter.intel.com> and search for
1158b8989db9SAlan	  'Linux Processor Microcode Data File'.
11598d86f390SPeter Oruba
116080cc9f10SPeter Orubaconfig MICROCODE_AMD
1161e43f6e67SBorislav Petkov	bool "AMD microcode loading support"
116280cc9f10SPeter Oruba	depends on MICROCODE
116380cc9f10SPeter Oruba	select FW_LOADER
11648f9ca475SIngo Molnar	---help---
116580cc9f10SPeter Oruba	  If you select this option, microcode patch loading support for AMD
116680cc9f10SPeter Oruba	  processors will be enabled.
116780cc9f10SPeter Oruba
1168506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE
11693c2362e6SHarvey Harrison	def_bool y
1170506f1d07SSam Ravnborg	depends on MICROCODE
1171506f1d07SSam Ravnborg
1172506f1d07SSam Ravnborgconfig X86_MSR
1173506f1d07SSam Ravnborg	tristate "/dev/cpu/*/msr - Model-specific register support"
11748f9ca475SIngo Molnar	---help---
1175506f1d07SSam Ravnborg	  This device gives privileged processes access to the x86
1176506f1d07SSam Ravnborg	  Model-Specific Registers (MSRs).  It is a character device with
1177506f1d07SSam Ravnborg	  major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1178506f1d07SSam Ravnborg	  MSR accesses are directed to a specific CPU on multi-processor
1179506f1d07SSam Ravnborg	  systems.
1180506f1d07SSam Ravnborg
1181506f1d07SSam Ravnborgconfig X86_CPUID
1182506f1d07SSam Ravnborg	tristate "/dev/cpu/*/cpuid - CPU information support"
11838f9ca475SIngo Molnar	---help---
1184506f1d07SSam Ravnborg	  This device gives processes access to the x86 CPUID instruction to
1185506f1d07SSam Ravnborg	  be executed on a specific processor.  It is a character device
1186506f1d07SSam Ravnborg	  with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1187506f1d07SSam Ravnborg	  /dev/cpu/31/cpuid.
1188506f1d07SSam Ravnborg
1189506f1d07SSam Ravnborgchoice
1190506f1d07SSam Ravnborg	prompt "High Memory Support"
11916fc108a0SJan Beulich	default HIGHMEM4G
1192506f1d07SSam Ravnborg	depends on X86_32
1193506f1d07SSam Ravnborg
1194506f1d07SSam Ravnborgconfig NOHIGHMEM
1195506f1d07SSam Ravnborg	bool "off"
1196506f1d07SSam Ravnborg	---help---
1197506f1d07SSam Ravnborg	  Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1198506f1d07SSam Ravnborg	  However, the address space of 32-bit x86 processors is only 4
1199506f1d07SSam Ravnborg	  Gigabytes large. That means that, if you have a large amount of
1200506f1d07SSam Ravnborg	  physical memory, not all of it can be "permanently mapped" by the
1201506f1d07SSam Ravnborg	  kernel. The physical memory that's not permanently mapped is called
1202506f1d07SSam Ravnborg	  "high memory".
1203506f1d07SSam Ravnborg
1204506f1d07SSam Ravnborg	  If you are compiling a kernel which will never run on a machine with
1205506f1d07SSam Ravnborg	  more than 1 Gigabyte total physical RAM, answer "off" here (default
1206506f1d07SSam Ravnborg	  choice and suitable for most users). This will result in a "3GB/1GB"
1207506f1d07SSam Ravnborg	  split: 3GB are mapped so that each process sees a 3GB virtual memory
1208506f1d07SSam Ravnborg	  space and the remaining part of the 4GB virtual memory space is used
1209506f1d07SSam Ravnborg	  by the kernel to permanently map as much physical memory as
1210506f1d07SSam Ravnborg	  possible.
1211506f1d07SSam Ravnborg
1212506f1d07SSam Ravnborg	  If the machine has between 1 and 4 Gigabytes physical RAM, then
1213506f1d07SSam Ravnborg	  answer "4GB" here.
1214506f1d07SSam Ravnborg
1215506f1d07SSam Ravnborg	  If more than 4 Gigabytes is used then answer "64GB" here. This
1216506f1d07SSam Ravnborg	  selection turns Intel PAE (Physical Address Extension) mode on.
1217506f1d07SSam Ravnborg	  PAE implements 3-level paging on IA32 processors. PAE is fully
1218506f1d07SSam Ravnborg	  supported by Linux, PAE mode is implemented on all recent Intel
1219506f1d07SSam Ravnborg	  processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1220506f1d07SSam Ravnborg	  then the kernel will not boot on CPUs that don't support PAE!
1221506f1d07SSam Ravnborg
1222506f1d07SSam Ravnborg	  The actual amount of total physical memory will either be
1223506f1d07SSam Ravnborg	  auto detected or can be forced by using a kernel command line option
1224506f1d07SSam Ravnborg	  such as "mem=256M". (Try "man bootparam" or see the documentation of
1225506f1d07SSam Ravnborg	  your boot loader (lilo or loadlin) about how to pass options to the
1226506f1d07SSam Ravnborg	  kernel at boot time.)
1227506f1d07SSam Ravnborg
1228506f1d07SSam Ravnborg	  If unsure, say "off".
1229506f1d07SSam Ravnborg
1230506f1d07SSam Ravnborgconfig HIGHMEM4G
1231506f1d07SSam Ravnborg	bool "4GB"
12328f9ca475SIngo Molnar	---help---
1233506f1d07SSam Ravnborg	  Select this if you have a 32-bit processor and between 1 and 4
1234506f1d07SSam Ravnborg	  gigabytes of physical RAM.
1235506f1d07SSam Ravnborg
1236506f1d07SSam Ravnborgconfig HIGHMEM64G
1237506f1d07SSam Ravnborg	bool "64GB"
1238eb068e78SH. Peter Anvin	depends on !M486
1239506f1d07SSam Ravnborg	select X86_PAE
12408f9ca475SIngo Molnar	---help---
1241506f1d07SSam Ravnborg	  Select this if you have a 32-bit processor and more than 4
1242506f1d07SSam Ravnborg	  gigabytes of physical RAM.
1243506f1d07SSam Ravnborg
1244506f1d07SSam Ravnborgendchoice
1245506f1d07SSam Ravnborg
1246506f1d07SSam Ravnborgchoice
12476a108a14SDavid Rientjes	prompt "Memory split" if EXPERT
1248506f1d07SSam Ravnborg	default VMSPLIT_3G
1249506f1d07SSam Ravnborg	depends on X86_32
12508f9ca475SIngo Molnar	---help---
1251506f1d07SSam Ravnborg	  Select the desired split between kernel and user memory.
1252506f1d07SSam Ravnborg
1253506f1d07SSam Ravnborg	  If the address range available to the kernel is less than the
1254506f1d07SSam Ravnborg	  physical memory installed, the remaining memory will be available
1255506f1d07SSam Ravnborg	  as "high memory". Accessing high memory is a little more costly
1256506f1d07SSam Ravnborg	  than low memory, as it needs to be mapped into the kernel first.
1257506f1d07SSam Ravnborg	  Note that increasing the kernel address space limits the range
1258506f1d07SSam Ravnborg	  available to user programs, making the address space there
1259506f1d07SSam Ravnborg	  tighter.  Selecting anything other than the default 3G/1G split
1260506f1d07SSam Ravnborg	  will also likely make your kernel incompatible with binary-only
1261506f1d07SSam Ravnborg	  kernel modules.
1262506f1d07SSam Ravnborg
1263506f1d07SSam Ravnborg	  If you are not absolutely sure what you are doing, leave this
1264506f1d07SSam Ravnborg	  option alone!
1265506f1d07SSam Ravnborg
1266506f1d07SSam Ravnborg	config VMSPLIT_3G
1267506f1d07SSam Ravnborg		bool "3G/1G user/kernel split"
1268506f1d07SSam Ravnborg	config VMSPLIT_3G_OPT
1269506f1d07SSam Ravnborg		depends on !X86_PAE
1270506f1d07SSam Ravnborg		bool "3G/1G user/kernel split (for full 1G low memory)"
1271506f1d07SSam Ravnborg	config VMSPLIT_2G
1272506f1d07SSam Ravnborg		bool "2G/2G user/kernel split"
1273506f1d07SSam Ravnborg	config VMSPLIT_2G_OPT
1274506f1d07SSam Ravnborg		depends on !X86_PAE
1275506f1d07SSam Ravnborg		bool "2G/2G user/kernel split (for full 2G low memory)"
1276506f1d07SSam Ravnborg	config VMSPLIT_1G
1277506f1d07SSam Ravnborg		bool "1G/3G user/kernel split"
1278506f1d07SSam Ravnborgendchoice
1279506f1d07SSam Ravnborg
1280506f1d07SSam Ravnborgconfig PAGE_OFFSET
1281506f1d07SSam Ravnborg	hex
1282506f1d07SSam Ravnborg	default 0xB0000000 if VMSPLIT_3G_OPT
1283506f1d07SSam Ravnborg	default 0x80000000 if VMSPLIT_2G
1284506f1d07SSam Ravnborg	default 0x78000000 if VMSPLIT_2G_OPT
1285506f1d07SSam Ravnborg	default 0x40000000 if VMSPLIT_1G
1286506f1d07SSam Ravnborg	default 0xC0000000
1287506f1d07SSam Ravnborg	depends on X86_32
1288506f1d07SSam Ravnborg
1289506f1d07SSam Ravnborgconfig HIGHMEM
12903c2362e6SHarvey Harrison	def_bool y
1291506f1d07SSam Ravnborg	depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1292506f1d07SSam Ravnborg
1293506f1d07SSam Ravnborgconfig X86_PAE
12949ba16087SJan Beulich	bool "PAE (Physical Address Extension) Support"
1295506f1d07SSam Ravnborg	depends on X86_32 && !HIGHMEM4G
12969d99c712SChristian Melki	select SWIOTLB
12978f9ca475SIngo Molnar	---help---
1298506f1d07SSam Ravnborg	  PAE is required for NX support, and furthermore enables
1299506f1d07SSam Ravnborg	  larger swapspace support for non-overcommit purposes. It
1300506f1d07SSam Ravnborg	  has the cost of more pagetable lookup overhead, and also
1301506f1d07SSam Ravnborg	  consumes more pagetable space per process.
1302506f1d07SSam Ravnborg
1303600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT
13043120e25eSJan Beulich	def_bool y
13053120e25eSJan Beulich	depends on X86_64 || X86_PAE
1306600715dcSJeremy Fitzhardinge
130766f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT
13083120e25eSJan Beulich	def_bool y
13093120e25eSJan Beulich	depends on X86_64 || HIGHMEM64G
131066f2b061SFUJITA Tomonori
131110971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES
1312e5008abeSLuis R. Rodriguez	def_bool y
1313e5008abeSLuis R. Rodriguez	depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
13148f9ca475SIngo Molnar	---help---
131510971ab2SIngo Molnar	  Certain kernel features effectively disable kernel
131610971ab2SIngo Molnar	  linear 1 GB mappings (even if the CPU otherwise
131710971ab2SIngo Molnar	  supports them), so don't confuse the user by printing
131810971ab2SIngo Molnar	  that we have them enabled.
13199e899816SNick Piggin
1320506f1d07SSam Ravnborg# Common NUMA Features
1321506f1d07SSam Ravnborgconfig NUMA
1322fd51b2d7SKOSAKI Motohiro	bool "Numa Memory Allocation and Scheduler Support"
1323506f1d07SSam Ravnborg	depends on SMP
1324b5660ba7SH. Peter Anvin	depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1325b5660ba7SH. Peter Anvin	default y if X86_BIGSMP
13268f9ca475SIngo Molnar	---help---
1327506f1d07SSam Ravnborg	  Enable NUMA (Non Uniform Memory Access) support.
1328fd51b2d7SKOSAKI Motohiro
1329506f1d07SSam Ravnborg	  The kernel will try to allocate memory used by a CPU on the
1330506f1d07SSam Ravnborg	  local memory controller of the CPU and add some more
1331506f1d07SSam Ravnborg	  NUMA awareness to the kernel.
1332506f1d07SSam Ravnborg
1333c280ea5eSIngo Molnar	  For 64-bit this is recommended if the system is Intel Core i7
1334fd51b2d7SKOSAKI Motohiro	  (or later), AMD Opteron, or EM64T NUMA.
1335fd51b2d7SKOSAKI Motohiro
1336b5660ba7SH. Peter Anvin	  For 32-bit this is only needed if you boot a 32-bit
13377cf6c945SDavid Rientjes	  kernel on a 64-bit NUMA platform.
1338fd51b2d7SKOSAKI Motohiro
1339fd51b2d7SKOSAKI Motohiro	  Otherwise, you should say N.
1340506f1d07SSam Ravnborg
1341eec1d4faSHans Rosenfeldconfig AMD_NUMA
13423c2362e6SHarvey Harrison	def_bool y
13433c2362e6SHarvey Harrison	prompt "Old style AMD Opteron NUMA detection"
13445da0ef9aSTejun Heo	depends on X86_64 && NUMA && PCI
13458f9ca475SIngo Molnar	---help---
1346eec1d4faSHans Rosenfeld	  Enable AMD NUMA node topology detection.  You should say Y here if
1347eec1d4faSHans Rosenfeld	  you have a multi processor AMD system. This uses an old method to
1348eec1d4faSHans Rosenfeld	  read the NUMA configuration directly from the builtin Northbridge
1349eec1d4faSHans Rosenfeld	  of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1350eec1d4faSHans Rosenfeld	  which also takes priority if both are compiled in.
1351506f1d07SSam Ravnborg
1352506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA
13533c2362e6SHarvey Harrison	def_bool y
13543c2362e6SHarvey Harrison	prompt "ACPI NUMA detection"
1355506f1d07SSam Ravnborg	depends on X86_64 && NUMA && ACPI && PCI
1356506f1d07SSam Ravnborg	select ACPI_NUMA
13578f9ca475SIngo Molnar	---help---
1358506f1d07SSam Ravnborg	  Enable ACPI SRAT based node topology detection.
1359506f1d07SSam Ravnborg
13606ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span
13616ec6e0d9SSuresh Siddha# other nodes.  Even though a pfn is valid and
13626ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not
13636ec6e0d9SSuresh Siddha# reside on that node.  See memmap_init_zone()
13646ec6e0d9SSuresh Siddha# for details.
13656ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES
13666ec6e0d9SSuresh Siddha	def_bool y
13676ec6e0d9SSuresh Siddha	depends on X86_64_ACPI_NUMA
13686ec6e0d9SSuresh Siddha
1369506f1d07SSam Ravnborgconfig NUMA_EMU
1370506f1d07SSam Ravnborg	bool "NUMA emulation"
13711b7e03efSTejun Heo	depends on NUMA
13728f9ca475SIngo Molnar	---help---
1373506f1d07SSam Ravnborg	  Enable NUMA emulation. A flat machine will be split
1374506f1d07SSam Ravnborg	  into virtual nodes when booted with "numa=fake=N", where N is the
1375506f1d07SSam Ravnborg	  number of nodes. This is only useful for debugging.
1376506f1d07SSam Ravnborg
1377506f1d07SSam Ravnborgconfig NODES_SHIFT
1378d25e26b6SLinus Torvalds	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
137951591e31SDavid Rientjes	range 1 10
138051591e31SDavid Rientjes	default "10" if MAXSMP
1381506f1d07SSam Ravnborg	default "6" if X86_64
1382506f1d07SSam Ravnborg	default "3"
1383506f1d07SSam Ravnborg	depends on NEED_MULTIPLE_NODES
13848f9ca475SIngo Molnar	---help---
13851184dc2fSMike Travis	  Specify the maximum number of NUMA Nodes available on the target
1386692105b8SMatt LaPlante	  system.  Increases memory reserved to accommodate various tables.
1387506f1d07SSam Ravnborg
1388506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT
13893c2362e6SHarvey Harrison	def_bool y
1390506f1d07SSam Ravnborg	depends on X86_32 && DISCONTIGMEM
1391506f1d07SSam Ravnborg
1392506f1d07SSam Ravnborgconfig NEED_NODE_MEMMAP_SIZE
13933c2362e6SHarvey Harrison	def_bool y
1394506f1d07SSam Ravnborg	depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1395506f1d07SSam Ravnborg
1396506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE
1397506f1d07SSam Ravnborg	def_bool y
13983b16651fSTejun Heo	depends on X86_32 && !NUMA
1399506f1d07SSam Ravnborg
1400506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE
1401506f1d07SSam Ravnborg	def_bool y
1402b263295dSChristoph Lameter	depends on NUMA && X86_32
1403506f1d07SSam Ravnborg
1404506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT
1405506f1d07SSam Ravnborg	def_bool y
1406b263295dSChristoph Lameter	depends on NUMA && X86_32
1407b263295dSChristoph Lameter
1408506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE
1409506f1d07SSam Ravnborg	def_bool y
14106ea30386SKees Cook	depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1411506f1d07SSam Ravnborg	select SPARSEMEM_STATIC if X86_32
1412506f1d07SSam Ravnborg	select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1413506f1d07SSam Ravnborg
14143b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT
14153b16651fSTejun Heo	def_bool y
14163b16651fSTejun Heo	depends on X86_64
14173b16651fSTejun Heo
1418506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL
1419506f1d07SSam Ravnborg	def_bool y
1420b263295dSChristoph Lameter	depends on ARCH_SPARSEMEM_ENABLE
1421506f1d07SSam Ravnborg
1422506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE
1423a0842b70SToshi Kani	bool "Enable sysfs memory/probe interface"
14243120e25eSJan Beulich	depends on X86_64 && MEMORY_HOTPLUG
1425a0842b70SToshi Kani	help
1426a0842b70SToshi Kani	  This option enables a sysfs memory/probe interface for testing.
1427a0842b70SToshi Kani	  See Documentation/memory-hotplug.txt for more information.
1428a0842b70SToshi Kani	  If you are unsure how to answer this question, answer N.
1429506f1d07SSam Ravnborg
14303b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT
14313b16651fSTejun Heo	def_bool y
14323b16651fSTejun Heo	depends on X86_64 && PROC_KCORE
14333b16651fSTejun Heo
1434a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE
1435a29815a3SAvi Kivity       hex
1436a29815a3SAvi Kivity       default 0 if X86_32
1437a29815a3SAvi Kivity       default 0xdead000000000000 if X86_64
1438a29815a3SAvi Kivity
1439506f1d07SSam Ravnborgsource "mm/Kconfig"
1440506f1d07SSam Ravnborg
14417a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE
14427a67832cSDan Williams	bool
14437a67832cSDan Williams
1444ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY
14457a67832cSDan Williams	tristate "Support non-standard NVDIMMs and ADR protected memory"
14469f53f9faSDan Williams	depends on PHYS_ADDR_T_64BIT
14479f53f9faSDan Williams	depends on BLK_DEV
14487a67832cSDan Williams	select X86_PMEM_LEGACY_DEVICE
14499f53f9faSDan Williams	select LIBNVDIMM
1450ec776ef6SChristoph Hellwig	help
1451ec776ef6SChristoph Hellwig	  Treat memory marked using the non-standard e820 type of 12 as used
1452ec776ef6SChristoph Hellwig	  by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1453ec776ef6SChristoph Hellwig	  The kernel will offer these regions to the 'pmem' driver so
1454ec776ef6SChristoph Hellwig	  they can be used for persistent storage.
1455ec776ef6SChristoph Hellwig
1456ec776ef6SChristoph Hellwig	  Say Y if unsure.
1457ec776ef6SChristoph Hellwig
1458506f1d07SSam Ravnborgconfig HIGHPTE
1459506f1d07SSam Ravnborg	bool "Allocate 3rd-level pagetables from highmem"
14606fc108a0SJan Beulich	depends on HIGHMEM
14618f9ca475SIngo Molnar	---help---
1462506f1d07SSam Ravnborg	  The VM uses one page table entry for each page of physical memory.
1463506f1d07SSam Ravnborg	  For systems with a lot of RAM, this can be wasteful of precious
1464506f1d07SSam Ravnborg	  low memory.  Setting this option will put user-space page table
1465506f1d07SSam Ravnborg	  entries in high memory.
1466506f1d07SSam Ravnborg
14679f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION
14689f077871SJeremy Fitzhardinge	bool "Check for low memory corruption"
14698f9ca475SIngo Molnar	---help---
14709f077871SJeremy Fitzhardinge	  Periodically check for memory corruption in low memory, which
14719f077871SJeremy Fitzhardinge	  is suspected to be caused by BIOS.  Even when enabled in the
14729f077871SJeremy Fitzhardinge	  configuration, it is disabled at runtime.  Enable it by
14739f077871SJeremy Fitzhardinge	  setting "memory_corruption_check=1" on the kernel command
14749f077871SJeremy Fitzhardinge	  line.  By default it scans the low 64k of memory every 60
14759f077871SJeremy Fitzhardinge	  seconds; see the memory_corruption_check_size and
14769f077871SJeremy Fitzhardinge	  memory_corruption_check_period parameters in
14779f077871SJeremy Fitzhardinge	  Documentation/kernel-parameters.txt to adjust this.
14789f077871SJeremy Fitzhardinge
14799f077871SJeremy Fitzhardinge	  When enabled with the default parameters, this option has
14809f077871SJeremy Fitzhardinge	  almost no overhead, as it reserves a relatively small amount
14819f077871SJeremy Fitzhardinge	  of memory and scans it infrequently.  It both detects corruption
14829f077871SJeremy Fitzhardinge	  and prevents it from affecting the running system.
14839f077871SJeremy Fitzhardinge
14849f077871SJeremy Fitzhardinge	  It is, however, intended as a diagnostic tool; if repeatable
14859f077871SJeremy Fitzhardinge	  BIOS-originated corruption always affects the same memory,
14869f077871SJeremy Fitzhardinge	  you can use memmap= to prevent the kernel from using that
14879f077871SJeremy Fitzhardinge	  memory.
14889f077871SJeremy Fitzhardinge
1489c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1490c885df50SJeremy Fitzhardinge	bool "Set the default setting of memory_corruption_check"
1491c885df50SJeremy Fitzhardinge	depends on X86_CHECK_BIOS_CORRUPTION
1492c885df50SJeremy Fitzhardinge	default y
14938f9ca475SIngo Molnar	---help---
1494c885df50SJeremy Fitzhardinge	  Set whether the default state of memory_corruption_check is
1495c885df50SJeremy Fitzhardinge	  on or off.
1496c885df50SJeremy Fitzhardinge
14979ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW
1498d0cd7425SH. Peter Anvin	int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1499d0cd7425SH. Peter Anvin	default 64
1500d0cd7425SH. Peter Anvin	range 4 640
15018f9ca475SIngo Molnar	---help---
1502d0cd7425SH. Peter Anvin	  Specify the amount of low memory to reserve for the BIOS.
1503fc381519SIngo Molnar
1504d0cd7425SH. Peter Anvin	  The first page contains BIOS data structures that the kernel
1505d0cd7425SH. Peter Anvin	  must not use, so that page must always be reserved.
1506fc381519SIngo Molnar
1507d0cd7425SH. Peter Anvin	  By default we reserve the first 64K of physical RAM, as a
1508d0cd7425SH. Peter Anvin	  number of BIOSes are known to corrupt that memory range
1509d0cd7425SH. Peter Anvin	  during events such as suspend/resume or monitor cable
1510d0cd7425SH. Peter Anvin	  insertion, so it must not be used by the kernel.
1511fc381519SIngo Molnar
1512d0cd7425SH. Peter Anvin	  You can set this to 4 if you are absolutely sure that you
1513d0cd7425SH. Peter Anvin	  trust the BIOS to get all its memory reservations and usages
1514d0cd7425SH. Peter Anvin	  right.  If you know your BIOS have problems beyond the
1515d0cd7425SH. Peter Anvin	  default 64K area, you can set this to 640 to avoid using the
1516d0cd7425SH. Peter Anvin	  entire low memory range.
1517d0cd7425SH. Peter Anvin
1518d0cd7425SH. Peter Anvin	  If you have doubts about the BIOS (e.g. suspend/resume does
1519d0cd7425SH. Peter Anvin	  not work or there's kernel crashes after certain hardware
1520d0cd7425SH. Peter Anvin	  hotplug events) then you might want to enable
1521d0cd7425SH. Peter Anvin	  X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1522d0cd7425SH. Peter Anvin	  typical corruption patterns.
1523d0cd7425SH. Peter Anvin
1524d0cd7425SH. Peter Anvin	  Leave this to the default value of 64 if you are unsure.
1525fc381519SIngo Molnar
1526506f1d07SSam Ravnborgconfig MATH_EMULATION
1527506f1d07SSam Ravnborg	bool
1528a5b9e5a2SAndy Lutomirski	depends on MODIFY_LDT_SYSCALL
1529506f1d07SSam Ravnborg	prompt "Math emulation" if X86_32
1530506f1d07SSam Ravnborg	---help---
1531506f1d07SSam Ravnborg	  Linux can emulate a math coprocessor (used for floating point
1532506f1d07SSam Ravnborg	  operations) if you don't have one. 486DX and Pentium processors have
1533506f1d07SSam Ravnborg	  a math coprocessor built in, 486SX and 386 do not, unless you added
1534506f1d07SSam Ravnborg	  a 487DX or 387, respectively. (The messages during boot time can
1535506f1d07SSam Ravnborg	  give you some hints here ["man dmesg"].) Everyone needs either a
1536506f1d07SSam Ravnborg	  coprocessor or this emulation.
1537506f1d07SSam Ravnborg
1538506f1d07SSam Ravnborg	  If you don't have a math coprocessor, you need to say Y here; if you
1539506f1d07SSam Ravnborg	  say Y here even though you have a coprocessor, the coprocessor will
1540506f1d07SSam Ravnborg	  be used nevertheless. (This behavior can be changed with the kernel
1541506f1d07SSam Ravnborg	  command line option "no387", which comes handy if your coprocessor
1542506f1d07SSam Ravnborg	  is broken. Try "man bootparam" or see the documentation of your boot
1543506f1d07SSam Ravnborg	  loader (lilo or loadlin) about how to pass options to the kernel at
1544506f1d07SSam Ravnborg	  boot time.) This means that it is a good idea to say Y here if you
1545506f1d07SSam Ravnborg	  intend to use this kernel on different machines.
1546506f1d07SSam Ravnborg
1547506f1d07SSam Ravnborg	  More information about the internals of the Linux math coprocessor
1548506f1d07SSam Ravnborg	  emulation can be found in <file:arch/x86/math-emu/README>.
1549506f1d07SSam Ravnborg
1550506f1d07SSam Ravnborg	  If you are not sure, say Y; apart from resulting in a 66 KB bigger
1551506f1d07SSam Ravnborg	  kernel, it won't hurt.
1552506f1d07SSam Ravnborg
1553506f1d07SSam Ravnborgconfig MTRR
15546fc108a0SJan Beulich	def_bool y
15556a108a14SDavid Rientjes	prompt "MTRR (Memory Type Range Register) support" if EXPERT
1556506f1d07SSam Ravnborg	---help---
1557506f1d07SSam Ravnborg	  On Intel P6 family processors (Pentium Pro, Pentium II and later)
1558506f1d07SSam Ravnborg	  the Memory Type Range Registers (MTRRs) may be used to control
1559506f1d07SSam Ravnborg	  processor access to memory ranges. This is most useful if you have
1560506f1d07SSam Ravnborg	  a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1561506f1d07SSam Ravnborg	  allows bus write transfers to be combined into a larger transfer
1562506f1d07SSam Ravnborg	  before bursting over the PCI/AGP bus. This can increase performance
1563506f1d07SSam Ravnborg	  of image write operations 2.5 times or more. Saying Y here creates a
1564506f1d07SSam Ravnborg	  /proc/mtrr file which may be used to manipulate your processor's
1565506f1d07SSam Ravnborg	  MTRRs. Typically the X server should use this.
1566506f1d07SSam Ravnborg
1567506f1d07SSam Ravnborg	  This code has a reasonably generic interface so that similar
1568506f1d07SSam Ravnborg	  control registers on other processors can be easily supported
1569506f1d07SSam Ravnborg	  as well:
1570506f1d07SSam Ravnborg
1571506f1d07SSam Ravnborg	  The Cyrix 6x86, 6x86MX and M II processors have Address Range
1572506f1d07SSam Ravnborg	  Registers (ARRs) which provide a similar functionality to MTRRs. For
1573506f1d07SSam Ravnborg	  these, the ARRs are used to emulate the MTRRs.
1574506f1d07SSam Ravnborg	  The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1575506f1d07SSam Ravnborg	  MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1576506f1d07SSam Ravnborg	  write-combining. All of these processors are supported by this code
1577506f1d07SSam Ravnborg	  and it makes sense to say Y here if you have one of them.
1578506f1d07SSam Ravnborg
1579506f1d07SSam Ravnborg	  Saying Y here also fixes a problem with buggy SMP BIOSes which only
1580506f1d07SSam Ravnborg	  set the MTRRs for the boot CPU and not for the secondary CPUs. This
1581506f1d07SSam Ravnborg	  can lead to all sorts of problems, so it's good to say Y here.
1582506f1d07SSam Ravnborg
1583506f1d07SSam Ravnborg	  You can safely say Y even if your machine doesn't have MTRRs, you'll
1584506f1d07SSam Ravnborg	  just add about 9 KB to your kernel.
1585506f1d07SSam Ravnborg
15867225e751SRandy Dunlap	  See <file:Documentation/x86/mtrr.txt> for more information.
1587506f1d07SSam Ravnborg
158895ffa243SYinghai Luconfig MTRR_SANITIZER
15892ffb3501SYinghai Lu	def_bool y
159095ffa243SYinghai Lu	prompt "MTRR cleanup support"
159195ffa243SYinghai Lu	depends on MTRR
15928f9ca475SIngo Molnar	---help---
1593aba3728cSThomas Gleixner	  Convert MTRR layout from continuous to discrete, so X drivers can
1594aba3728cSThomas Gleixner	  add writeback entries.
159595ffa243SYinghai Lu
1596aba3728cSThomas Gleixner	  Can be disabled with disable_mtrr_cleanup on the kernel command line.
1597692105b8SMatt LaPlante	  The largest mtrr entry size for a continuous block can be set with
1598aba3728cSThomas Gleixner	  mtrr_chunk_size.
159995ffa243SYinghai Lu
16002ffb3501SYinghai Lu	  If unsure, say Y.
160195ffa243SYinghai Lu
160295ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT
1603f5098d62SYinghai Lu	int "MTRR cleanup enable value (0-1)"
1604f5098d62SYinghai Lu	range 0 1
1605f5098d62SYinghai Lu	default "0"
160695ffa243SYinghai Lu	depends on MTRR_SANITIZER
16078f9ca475SIngo Molnar	---help---
1608f5098d62SYinghai Lu	  Enable mtrr cleanup default value
160995ffa243SYinghai Lu
161012031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
161112031a62SYinghai Lu	int "MTRR cleanup spare reg num (0-7)"
161212031a62SYinghai Lu	range 0 7
161312031a62SYinghai Lu	default "1"
161412031a62SYinghai Lu	depends on MTRR_SANITIZER
16158f9ca475SIngo Molnar	---help---
161612031a62SYinghai Lu	  mtrr cleanup spare entries default, it can be changed via
1617aba3728cSThomas Gleixner	  mtrr_spare_reg_nr=N on the kernel command line.
161812031a62SYinghai Lu
16192e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT
16206fc108a0SJan Beulich	def_bool y
16216a108a14SDavid Rientjes	prompt "x86 PAT support" if EXPERT
16222a8a2719SIngo Molnar	depends on MTRR
16238f9ca475SIngo Molnar	---help---
16242e5d9c85Svenkatesh.pallipadi@intel.com	  Use PAT attributes to setup page level cache control.
1625042b78e4SVenki Pallipadi
16262e5d9c85Svenkatesh.pallipadi@intel.com	  PATs are the modern equivalents of MTRRs and are much more
16272e5d9c85Svenkatesh.pallipadi@intel.com	  flexible than MTRRs.
16282e5d9c85Svenkatesh.pallipadi@intel.com
16292e5d9c85Svenkatesh.pallipadi@intel.com	  Say N here if you see bootup problems (boot crash, boot hang,
1630042b78e4SVenki Pallipadi	  spontaneous reboots) or a non-working video driver.
16312e5d9c85Svenkatesh.pallipadi@intel.com
16322e5d9c85Svenkatesh.pallipadi@intel.com	  If unsure, say Y.
16332e5d9c85Svenkatesh.pallipadi@intel.com
163446cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED
163546cf98cdSVenkatesh Pallipadi	def_bool y
163646cf98cdSVenkatesh Pallipadi	depends on X86_PAT
163746cf98cdSVenkatesh Pallipadi
1638628c6246SH. Peter Anvinconfig ARCH_RANDOM
1639628c6246SH. Peter Anvin	def_bool y
1640628c6246SH. Peter Anvin	prompt "x86 architectural random number generator" if EXPERT
1641628c6246SH. Peter Anvin	---help---
1642628c6246SH. Peter Anvin	  Enable the x86 architectural RDRAND instruction
1643628c6246SH. Peter Anvin	  (Intel Bull Mountain technology) to generate random numbers.
1644628c6246SH. Peter Anvin	  If supported, this is a high bandwidth, cryptographically
1645628c6246SH. Peter Anvin	  secure hardware random number generator.
1646628c6246SH. Peter Anvin
164751ae4a2dSH. Peter Anvinconfig X86_SMAP
164851ae4a2dSH. Peter Anvin	def_bool y
164951ae4a2dSH. Peter Anvin	prompt "Supervisor Mode Access Prevention" if EXPERT
165051ae4a2dSH. Peter Anvin	---help---
165151ae4a2dSH. Peter Anvin	  Supervisor Mode Access Prevention (SMAP) is a security
165251ae4a2dSH. Peter Anvin	  feature in newer Intel processors.  There is a small
165351ae4a2dSH. Peter Anvin	  performance cost if this enabled and turned on; there is
165451ae4a2dSH. Peter Anvin	  also a small increase in the kernel size if this is enabled.
165551ae4a2dSH. Peter Anvin
165651ae4a2dSH. Peter Anvin	  If unsure, say Y.
165751ae4a2dSH. Peter Anvin
165872e9b5feSDave Hansenconfig X86_INTEL_MPX
165972e9b5feSDave Hansen	prompt "Intel MPX (Memory Protection Extensions)"
166072e9b5feSDave Hansen	def_bool n
166172e9b5feSDave Hansen	depends on CPU_SUP_INTEL
166272e9b5feSDave Hansen	---help---
166372e9b5feSDave Hansen	  MPX provides hardware features that can be used in
166472e9b5feSDave Hansen	  conjunction with compiler-instrumented code to check
166572e9b5feSDave Hansen	  memory references.  It is designed to detect buffer
166672e9b5feSDave Hansen	  overflow or underflow bugs.
166772e9b5feSDave Hansen
166872e9b5feSDave Hansen	  This option enables running applications which are
166972e9b5feSDave Hansen	  instrumented or otherwise use MPX.  It does not use MPX
167072e9b5feSDave Hansen	  itself inside the kernel or to protect the kernel
167172e9b5feSDave Hansen	  against bad memory references.
167272e9b5feSDave Hansen
167372e9b5feSDave Hansen	  Enabling this option will make the kernel larger:
167472e9b5feSDave Hansen	  ~8k of kernel text and 36 bytes of data on a 64-bit
167572e9b5feSDave Hansen	  defconfig.  It adds a long to the 'mm_struct' which
167672e9b5feSDave Hansen	  will increase the kernel memory overhead of each
167772e9b5feSDave Hansen	  process and adds some branches to paths used during
167872e9b5feSDave Hansen	  exec() and munmap().
167972e9b5feSDave Hansen
168072e9b5feSDave Hansen	  For details, see Documentation/x86/intel_mpx.txt
168172e9b5feSDave Hansen
168272e9b5feSDave Hansen	  If unsure, say N.
168372e9b5feSDave Hansen
1684506f1d07SSam Ravnborgconfig EFI
16859ba16087SJan Beulich	bool "EFI runtime service support"
16865b83683fSHuang, Ying	depends on ACPI
1687f6ce5002SSergey Vlasov	select UCS2_STRING
1688022ee6c5SArd Biesheuvel	select EFI_RUNTIME_WRAPPERS
1689506f1d07SSam Ravnborg	---help---
16908b2cb7a8SHuang, Ying	  This enables the kernel to use EFI runtime services that are
1691506f1d07SSam Ravnborg	  available (such as the EFI variable services).
1692506f1d07SSam Ravnborg
16938b2cb7a8SHuang, Ying	  This option is only useful on systems that have EFI firmware.
16948b2cb7a8SHuang, Ying	  In addition, you should use the latest ELILO loader available
16958b2cb7a8SHuang, Ying	  at <http://elilo.sourceforge.net> in order to take advantage
16968b2cb7a8SHuang, Ying	  of EFI runtime services. However, even with this option, the
16978b2cb7a8SHuang, Ying	  resultant kernel should continue to boot on existing non-EFI
16988b2cb7a8SHuang, Ying	  platforms.
1699506f1d07SSam Ravnborg
1700291f3632SMatt Flemingconfig EFI_STUB
1701291f3632SMatt Fleming       bool "EFI stub support"
1702b16d8c23SMatt Fleming       depends on EFI && !X86_USE_3DNOW
17037b2a583aSMatt Fleming       select RELOCATABLE
1704291f3632SMatt Fleming       ---help---
1705291f3632SMatt Fleming          This kernel feature allows a bzImage to be loaded directly
1706291f3632SMatt Fleming	  by EFI firmware without the use of a bootloader.
1707291f3632SMatt Fleming
17084172fe2fSRoy Franz	  See Documentation/efi-stub.txt for more information.
17090c759662SMatt Fleming
17107d453eeeSMatt Flemingconfig EFI_MIXED
17117d453eeeSMatt Fleming	bool "EFI mixed-mode support"
17127d453eeeSMatt Fleming	depends on EFI_STUB && X86_64
17137d453eeeSMatt Fleming	---help---
17147d453eeeSMatt Fleming	   Enabling this feature allows a 64-bit kernel to be booted
17157d453eeeSMatt Fleming	   on a 32-bit firmware, provided that your CPU supports 64-bit
17167d453eeeSMatt Fleming	   mode.
17177d453eeeSMatt Fleming
17187d453eeeSMatt Fleming	   Note that it is not possible to boot a mixed-mode enabled
17197d453eeeSMatt Fleming	   kernel via the EFI boot stub - a bootloader that supports
17207d453eeeSMatt Fleming	   the EFI handover protocol must be used.
17217d453eeeSMatt Fleming
17227d453eeeSMatt Fleming	   If unsure, say N.
17237d453eeeSMatt Fleming
1724506f1d07SSam Ravnborgconfig SECCOMP
17253c2362e6SHarvey Harrison	def_bool y
17263c2362e6SHarvey Harrison	prompt "Enable seccomp to safely compute untrusted bytecode"
17278f9ca475SIngo Molnar	---help---
1728506f1d07SSam Ravnborg	  This kernel feature is useful for number crunching applications
1729506f1d07SSam Ravnborg	  that may need to compute untrusted bytecode during their
1730506f1d07SSam Ravnborg	  execution. By using pipes or other transports made available to
1731506f1d07SSam Ravnborg	  the process as file descriptors supporting the read/write
1732506f1d07SSam Ravnborg	  syscalls, it's possible to isolate those applications in
1733506f1d07SSam Ravnborg	  their own address space using seccomp. Once seccomp is
17349c0bbee8SAlexey Dobriyan	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1735506f1d07SSam Ravnborg	  and the task is only allowed to execute a few safe syscalls
1736506f1d07SSam Ravnborg	  defined by each seccomp mode.
1737506f1d07SSam Ravnborg
1738506f1d07SSam Ravnborg	  If unsure, say Y. Only embedded should say N here.
1739506f1d07SSam Ravnborg
1740506f1d07SSam Ravnborgsource kernel/Kconfig.hz
1741506f1d07SSam Ravnborg
1742506f1d07SSam Ravnborgconfig KEXEC
1743506f1d07SSam Ravnborg	bool "kexec system call"
17442965faa5SDave Young	select KEXEC_CORE
17458f9ca475SIngo Molnar	---help---
1746506f1d07SSam Ravnborg	  kexec is a system call that implements the ability to shutdown your
1747506f1d07SSam Ravnborg	  current kernel, and to start another kernel.  It is like a reboot
1748506f1d07SSam Ravnborg	  but it is independent of the system firmware.   And like a reboot
1749506f1d07SSam Ravnborg	  you can start any kernel with it, not just Linux.
1750506f1d07SSam Ravnborg
1751506f1d07SSam Ravnborg	  The name comes from the similarity to the exec system call.
1752506f1d07SSam Ravnborg
1753506f1d07SSam Ravnborg	  It is an ongoing process to be certain the hardware in a machine
1754506f1d07SSam Ravnborg	  is properly shutdown, so do not be surprised if this code does not
1755bf220695SGeert Uytterhoeven	  initially work for you.  As of this writing the exact hardware
1756bf220695SGeert Uytterhoeven	  interface is strongly in flux, so no good recommendation can be
1757bf220695SGeert Uytterhoeven	  made.
1758506f1d07SSam Ravnborg
175974ca317cSVivek Goyalconfig KEXEC_FILE
176074ca317cSVivek Goyal	bool "kexec file based system call"
17612965faa5SDave Young	select KEXEC_CORE
176274ca317cSVivek Goyal	select BUILD_BIN2C
176374ca317cSVivek Goyal	depends on X86_64
176474ca317cSVivek Goyal	depends on CRYPTO=y
176574ca317cSVivek Goyal	depends on CRYPTO_SHA256=y
176674ca317cSVivek Goyal	---help---
176774ca317cSVivek Goyal	  This is new version of kexec system call. This system call is
176874ca317cSVivek Goyal	  file based and takes file descriptors as system call argument
176974ca317cSVivek Goyal	  for kernel and initramfs as opposed to list of segments as
177074ca317cSVivek Goyal	  accepted by previous system call.
177174ca317cSVivek Goyal
17728e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG
17738e7d8381SVivek Goyal	bool "Verify kernel signature during kexec_file_load() syscall"
177474ca317cSVivek Goyal	depends on KEXEC_FILE
17758e7d8381SVivek Goyal	---help---
17768e7d8381SVivek Goyal	  This option makes kernel signature verification mandatory for
1777d8eb8940SBorislav Petkov	  the kexec_file_load() syscall.
17788e7d8381SVivek Goyal
1779d8eb8940SBorislav Petkov	  In addition to that option, you need to enable signature
1780d8eb8940SBorislav Petkov	  verification for the corresponding kernel image type being
1781d8eb8940SBorislav Petkov	  loaded in order for this to work.
17828e7d8381SVivek Goyal
17838e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG
17848e7d8381SVivek Goyal	bool "Enable bzImage signature verification support"
17858e7d8381SVivek Goyal	depends on KEXEC_VERIFY_SIG
17868e7d8381SVivek Goyal	depends on SIGNED_PE_FILE_VERIFICATION
17878e7d8381SVivek Goyal	select SYSTEM_TRUSTED_KEYRING
17888e7d8381SVivek Goyal	---help---
17898e7d8381SVivek Goyal	  Enable bzImage signature verification support.
17908e7d8381SVivek Goyal
1791506f1d07SSam Ravnborgconfig CRASH_DUMP
179204b69447SPavel Machek	bool "kernel crash dumps"
1793506f1d07SSam Ravnborg	depends on X86_64 || (X86_32 && HIGHMEM)
17948f9ca475SIngo Molnar	---help---
1795506f1d07SSam Ravnborg	  Generate crash dump after being started by kexec.
1796506f1d07SSam Ravnborg	  This should be normally only set in special crash dump kernels
1797506f1d07SSam Ravnborg	  which are loaded in the main kernel with kexec-tools into
1798506f1d07SSam Ravnborg	  a specially reserved region and then later executed after
1799506f1d07SSam Ravnborg	  a crash by kdump/kexec. The crash dump kernel must be compiled
1800506f1d07SSam Ravnborg	  to a memory address not used by the main kernel or BIOS using
1801506f1d07SSam Ravnborg	  PHYSICAL_START, or it must be built as a relocatable image
1802506f1d07SSam Ravnborg	  (CONFIG_RELOCATABLE=y).
1803506f1d07SSam Ravnborg	  For more details see Documentation/kdump/kdump.txt
1804506f1d07SSam Ravnborg
18053ab83521SHuang Yingconfig KEXEC_JUMP
18066ea30386SKees Cook	bool "kexec jump"
1807fee7b0d8SHuang Ying	depends on KEXEC && HIBERNATION
18088f9ca475SIngo Molnar	---help---
180989081d17SHuang Ying	  Jump between original kernel and kexeced kernel and invoke
181089081d17SHuang Ying	  code in physical address mode via KEXEC
18113ab83521SHuang Ying
1812506f1d07SSam Ravnborgconfig PHYSICAL_START
18136a108a14SDavid Rientjes	hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1814ceefccc9SH. Peter Anvin	default "0x1000000"
18158f9ca475SIngo Molnar	---help---
1816506f1d07SSam Ravnborg	  This gives the physical address where the kernel is loaded.
1817506f1d07SSam Ravnborg
1818506f1d07SSam Ravnborg	  If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1819506f1d07SSam Ravnborg	  bzImage will decompress itself to above physical address and
1820506f1d07SSam Ravnborg	  run from there. Otherwise, bzImage will run from the address where
1821506f1d07SSam Ravnborg	  it has been loaded by the boot loader and will ignore above physical
1822506f1d07SSam Ravnborg	  address.
1823506f1d07SSam Ravnborg
1824506f1d07SSam Ravnborg	  In normal kdump cases one does not have to set/change this option
1825506f1d07SSam Ravnborg	  as now bzImage can be compiled as a completely relocatable image
1826506f1d07SSam Ravnborg	  (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1827506f1d07SSam Ravnborg	  address. This option is mainly useful for the folks who don't want
1828506f1d07SSam Ravnborg	  to use a bzImage for capturing the crash dump and want to use a
1829506f1d07SSam Ravnborg	  vmlinux instead. vmlinux is not relocatable hence a kernel needs
1830506f1d07SSam Ravnborg	  to be specifically compiled to run from a specific memory area
1831506f1d07SSam Ravnborg	  (normally a reserved region) and this option comes handy.
1832506f1d07SSam Ravnborg
1833ceefccc9SH. Peter Anvin	  So if you are using bzImage for capturing the crash dump,
1834ceefccc9SH. Peter Anvin	  leave the value here unchanged to 0x1000000 and set
1835ceefccc9SH. Peter Anvin	  CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1836ceefccc9SH. Peter Anvin	  for capturing the crash dump change this value to start of
1837ceefccc9SH. Peter Anvin	  the reserved region.  In other words, it can be set based on
1838ceefccc9SH. Peter Anvin	  the "X" value as specified in the "crashkernel=YM@XM"
1839ceefccc9SH. Peter Anvin	  command line boot parameter passed to the panic-ed
1840ceefccc9SH. Peter Anvin	  kernel. Please take a look at Documentation/kdump/kdump.txt
1841ceefccc9SH. Peter Anvin	  for more details about crash dumps.
1842506f1d07SSam Ravnborg
1843506f1d07SSam Ravnborg	  Usage of bzImage for capturing the crash dump is recommended as
1844506f1d07SSam Ravnborg	  one does not have to build two kernels. Same kernel can be used
1845506f1d07SSam Ravnborg	  as production kernel and capture kernel. Above option should have
1846506f1d07SSam Ravnborg	  gone away after relocatable bzImage support is introduced. But it
1847506f1d07SSam Ravnborg	  is present because there are users out there who continue to use
1848506f1d07SSam Ravnborg	  vmlinux for dump capture. This option should go away down the
1849506f1d07SSam Ravnborg	  line.
1850506f1d07SSam Ravnborg
1851506f1d07SSam Ravnborg	  Don't change this unless you know what you are doing.
1852506f1d07SSam Ravnborg
1853506f1d07SSam Ravnborgconfig RELOCATABLE
185426717808SH. Peter Anvin	bool "Build a relocatable kernel"
185526717808SH. Peter Anvin	default y
18568f9ca475SIngo Molnar	---help---
1857506f1d07SSam Ravnborg	  This builds a kernel image that retains relocation information
1858506f1d07SSam Ravnborg	  so it can be loaded someplace besides the default 1MB.
1859506f1d07SSam Ravnborg	  The relocations tend to make the kernel binary about 10% larger,
1860506f1d07SSam Ravnborg	  but are discarded at runtime.
1861506f1d07SSam Ravnborg
1862506f1d07SSam Ravnborg	  One use is for the kexec on panic case where the recovery kernel
1863506f1d07SSam Ravnborg	  must live at a different physical address than the primary
1864506f1d07SSam Ravnborg	  kernel.
1865506f1d07SSam Ravnborg
1866506f1d07SSam Ravnborg	  Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1867506f1d07SSam Ravnborg	  it has been loaded at and the compile time physical address
18688ab3820fSKees Cook	  (CONFIG_PHYSICAL_START) is used as the minimum location.
1869506f1d07SSam Ravnborg
18708ab3820fSKees Cookconfig RANDOMIZE_BASE
18718ab3820fSKees Cook	bool "Randomize the address of the kernel image"
18728ab3820fSKees Cook	depends on RELOCATABLE
18738ab3820fSKees Cook	default n
18748ab3820fSKees Cook	---help---
18758ab3820fSKees Cook	   Randomizes the physical and virtual address at which the
18768ab3820fSKees Cook	   kernel image is decompressed, as a security feature that
18778ab3820fSKees Cook	   deters exploit attempts relying on knowledge of the location
18788ab3820fSKees Cook	   of kernel internals.
18798ab3820fSKees Cook
1880a653f356SKees Cook	   Entropy is generated using the RDRAND instruction if it is
1881a653f356SKees Cook	   supported. If RDTSC is supported, it is used as well. If
1882a653f356SKees Cook	   neither RDRAND nor RDTSC are supported, then randomness is
1883a653f356SKees Cook	   read from the i8254 timer.
18848ab3820fSKees Cook
18858ab3820fSKees Cook	   The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1886a653f356SKees Cook	   and aligned according to PHYSICAL_ALIGN. Since the kernel is
1887a653f356SKees Cook	   built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1888a653f356SKees Cook	   minimum of 2MiB, only 10 bits of entropy is theoretically
1889a653f356SKees Cook	   possible. At best, due to page table layouts, 64-bit can use
1890a653f356SKees Cook	   9 bits of entropy and 32-bit uses 8 bits.
18918ab3820fSKees Cook
1892da2b6fb9SKees Cook	   If unsure, say N.
1893da2b6fb9SKees Cook
18948ab3820fSKees Cookconfig RANDOMIZE_BASE_MAX_OFFSET
1895da2b6fb9SKees Cook	hex "Maximum kASLR offset allowed" if EXPERT
18968ab3820fSKees Cook	depends on RANDOMIZE_BASE
18976145cfe3SKees Cook	range 0x0 0x20000000 if X86_32
18986145cfe3SKees Cook	default "0x20000000" if X86_32
18996145cfe3SKees Cook	range 0x0 0x40000000 if X86_64
19006145cfe3SKees Cook	default "0x40000000" if X86_64
19018ab3820fSKees Cook	---help---
1902da2b6fb9SKees Cook	  The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1903da2b6fb9SKees Cook	  memory is used to determine the maximal offset in bytes that will
1904da2b6fb9SKees Cook	  be applied to the kernel when kernel Address Space Layout
1905da2b6fb9SKees Cook	  Randomization (kASLR) is active. This must be a multiple of
1906da2b6fb9SKees Cook	  PHYSICAL_ALIGN.
19076145cfe3SKees Cook
1908da2b6fb9SKees Cook	  On 32-bit this is limited to 512MiB by page table layouts. The
1909da2b6fb9SKees Cook	  default is 512MiB.
19106145cfe3SKees Cook
19116145cfe3SKees Cook	  On 64-bit this is limited by how the kernel fixmap page table is
1912da2b6fb9SKees Cook	  positioned, so this cannot be larger than 1GiB currently. Without
1913da2b6fb9SKees Cook	  RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1914da2b6fb9SKees Cook	  and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1915da2b6fb9SKees Cook	  modules area will shrink to compensate, up to the current maximum
1916da2b6fb9SKees Cook	  1GiB to 1GiB split. The default is 1GiB.
1917da2b6fb9SKees Cook
1918da2b6fb9SKees Cook	  If unsure, leave at the default value.
19198ab3820fSKees Cook
19208ab3820fSKees Cook# Relocation on x86 needs some additional build support
1921845adf72SH. Peter Anvinconfig X86_NEED_RELOCS
1922845adf72SH. Peter Anvin	def_bool y
19238ab3820fSKees Cook	depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1924845adf72SH. Peter Anvin
1925506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN
1926a0215061SKees Cook	hex "Alignment value to which kernel should be aligned"
19278ab3820fSKees Cook	default "0x200000"
1928a0215061SKees Cook	range 0x2000 0x1000000 if X86_32
1929a0215061SKees Cook	range 0x200000 0x1000000 if X86_64
19308f9ca475SIngo Molnar	---help---
1931506f1d07SSam Ravnborg	  This value puts the alignment restrictions on physical address
1932506f1d07SSam Ravnborg	  where kernel is loaded and run from. Kernel is compiled for an
1933506f1d07SSam Ravnborg	  address which meets above alignment restriction.
1934506f1d07SSam Ravnborg
1935506f1d07SSam Ravnborg	  If bootloader loads the kernel at a non-aligned address and
1936506f1d07SSam Ravnborg	  CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1937506f1d07SSam Ravnborg	  address aligned to above value and run from there.
1938506f1d07SSam Ravnborg
1939506f1d07SSam Ravnborg	  If bootloader loads the kernel at a non-aligned address and
1940506f1d07SSam Ravnborg	  CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1941506f1d07SSam Ravnborg	  load address and decompress itself to the address it has been
1942506f1d07SSam Ravnborg	  compiled for and run from there. The address for which kernel is
1943506f1d07SSam Ravnborg	  compiled already meets above alignment restrictions. Hence the
1944506f1d07SSam Ravnborg	  end result is that kernel runs from a physical address meeting
1945506f1d07SSam Ravnborg	  above alignment restrictions.
1946506f1d07SSam Ravnborg
1947a0215061SKees Cook	  On 32-bit this value must be a multiple of 0x2000. On 64-bit
1948a0215061SKees Cook	  this value must be a multiple of 0x200000.
1949a0215061SKees Cook
1950506f1d07SSam Ravnborg	  Don't change this unless you know what you are doing.
1951506f1d07SSam Ravnborg
1952506f1d07SSam Ravnborgconfig HOTPLUG_CPU
19537c13e6a3SDimitri Sivanich	bool "Support for hot-pluggable CPUs"
195440b31360SStephen Rothwell	depends on SMP
1955506f1d07SSam Ravnborg	---help---
19567c13e6a3SDimitri Sivanich	  Say Y here to allow turning CPUs off and on. CPUs can be
19577c13e6a3SDimitri Sivanich	  controlled through /sys/devices/system/cpu.
19587c13e6a3SDimitri Sivanich	  ( Note: power management support will enable this option
19597c13e6a3SDimitri Sivanich	    automatically on SMP systems. )
19607c13e6a3SDimitri Sivanich	  Say N if you want to disable CPU hotplug.
1961506f1d07SSam Ravnborg
196280aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0
196380aa1dffSFenghua Yu	bool "Set default setting of cpu0_hotpluggable"
196480aa1dffSFenghua Yu	default n
19652c922cd0SKees Cook	depends on HOTPLUG_CPU
196680aa1dffSFenghua Yu	---help---
196780aa1dffSFenghua Yu	  Set whether default state of cpu0_hotpluggable is on or off.
196880aa1dffSFenghua Yu
196980aa1dffSFenghua Yu	  Say Y here to enable CPU0 hotplug by default. If this switch
197080aa1dffSFenghua Yu	  is turned on, there is no need to give cpu0_hotplug kernel
197180aa1dffSFenghua Yu	  parameter and the CPU0 hotplug feature is enabled by default.
197280aa1dffSFenghua Yu
197380aa1dffSFenghua Yu	  Please note: there are two known CPU0 dependencies if you want
197480aa1dffSFenghua Yu	  to enable the CPU0 hotplug feature either by this switch or by
197580aa1dffSFenghua Yu	  cpu0_hotplug kernel parameter.
197680aa1dffSFenghua Yu
197780aa1dffSFenghua Yu	  First, resume from hibernate or suspend always starts from CPU0.
197880aa1dffSFenghua Yu	  So hibernate and suspend are prevented if CPU0 is offline.
197980aa1dffSFenghua Yu
198080aa1dffSFenghua Yu	  Second dependency is PIC interrupts always go to CPU0. CPU0 can not
198180aa1dffSFenghua Yu	  offline if any interrupt can not migrate out of CPU0. There may
198280aa1dffSFenghua Yu	  be other CPU0 dependencies.
198380aa1dffSFenghua Yu
198480aa1dffSFenghua Yu	  Please make sure the dependencies are under your control before
198580aa1dffSFenghua Yu	  you enable this feature.
198680aa1dffSFenghua Yu
198780aa1dffSFenghua Yu	  Say N if you don't want to enable CPU0 hotplug feature by default.
198880aa1dffSFenghua Yu	  You still can enable the CPU0 hotplug feature at boot by kernel
198980aa1dffSFenghua Yu	  parameter cpu0_hotplug.
199080aa1dffSFenghua Yu
1991a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0
1992a71c8bc5SFenghua Yu	def_bool n
1993a71c8bc5SFenghua Yu	prompt "Debug CPU0 hotplug"
19942c922cd0SKees Cook	depends on HOTPLUG_CPU
1995a71c8bc5SFenghua Yu	---help---
1996a71c8bc5SFenghua Yu	  Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1997a71c8bc5SFenghua Yu	  soon as possible and boots up userspace with CPU0 offlined. User
1998a71c8bc5SFenghua Yu	  can online CPU0 back after boot time.
1999a71c8bc5SFenghua Yu
2000a71c8bc5SFenghua Yu	  To debug CPU0 hotplug, you need to enable CPU0 offline/online
2001a71c8bc5SFenghua Yu	  feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2002a71c8bc5SFenghua Yu	  compilation or giving cpu0_hotplug kernel parameter at boot.
2003a71c8bc5SFenghua Yu
2004a71c8bc5SFenghua Yu	  If unsure, say N.
2005a71c8bc5SFenghua Yu
2006506f1d07SSam Ravnborgconfig COMPAT_VDSO
2007b0b49f26SAndy Lutomirski	def_bool n
2008b0b49f26SAndy Lutomirski	prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
2009af65d648SRoland McGrath	depends on X86_32 || IA32_EMULATION
20108f9ca475SIngo Molnar	---help---
2011b0b49f26SAndy Lutomirski	  Certain buggy versions of glibc will crash if they are
2012b0b49f26SAndy Lutomirski	  presented with a 32-bit vDSO that is not mapped at the address
2013b0b49f26SAndy Lutomirski	  indicated in its segment table.
2014e84446deSRandy Dunlap
2015b0b49f26SAndy Lutomirski	  The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2016b0b49f26SAndy Lutomirski	  and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2017b0b49f26SAndy Lutomirski	  49ad572a70b8aeb91e57483a11dd1b77e31c4468.  Glibc 2.3.3 is
2018b0b49f26SAndy Lutomirski	  the only released version with the bug, but OpenSUSE 9
2019b0b49f26SAndy Lutomirski	  contains a buggy "glibc 2.3.2".
2020506f1d07SSam Ravnborg
2021b0b49f26SAndy Lutomirski	  The symptom of the bug is that everything crashes on startup, saying:
2022b0b49f26SAndy Lutomirski	  dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2023b0b49f26SAndy Lutomirski
2024b0b49f26SAndy Lutomirski	  Saying Y here changes the default value of the vdso32 boot
2025b0b49f26SAndy Lutomirski	  option from 1 to 0, which turns off the 32-bit vDSO entirely.
2026b0b49f26SAndy Lutomirski	  This works around the glibc bug but hurts performance.
2027b0b49f26SAndy Lutomirski
2028b0b49f26SAndy Lutomirski	  If unsure, say N: if you are compiling your own kernel, you
2029b0b49f26SAndy Lutomirski	  are unlikely to be using a buggy version of glibc.
2030506f1d07SSam Ravnborg
20313dc33bd3SKees Cookchoice
20323dc33bd3SKees Cook	prompt "vsyscall table for legacy applications"
20333dc33bd3SKees Cook	depends on X86_64
20343dc33bd3SKees Cook	default LEGACY_VSYSCALL_EMULATE
20353dc33bd3SKees Cook	help
20363dc33bd3SKees Cook	  Legacy user code that does not know how to find the vDSO expects
20373dc33bd3SKees Cook	  to be able to issue three syscalls by calling fixed addresses in
20383dc33bd3SKees Cook	  kernel space. Since this location is not randomized with ASLR,
20393dc33bd3SKees Cook	  it can be used to assist security vulnerability exploitation.
20403dc33bd3SKees Cook
20413dc33bd3SKees Cook	  This setting can be changed at boot time via the kernel command
20423dc33bd3SKees Cook	  line parameter vsyscall=[native|emulate|none].
20433dc33bd3SKees Cook
20443dc33bd3SKees Cook	  On a system with recent enough glibc (2.14 or newer) and no
20453dc33bd3SKees Cook	  static binaries, you can say None without a performance penalty
20463dc33bd3SKees Cook	  to improve security.
20473dc33bd3SKees Cook
20483dc33bd3SKees Cook	  If unsure, select "Emulate".
20493dc33bd3SKees Cook
20503dc33bd3SKees Cook	config LEGACY_VSYSCALL_NATIVE
20513dc33bd3SKees Cook		bool "Native"
20523dc33bd3SKees Cook		help
20533dc33bd3SKees Cook		  Actual executable code is located in the fixed vsyscall
20543dc33bd3SKees Cook		  address mapping, implementing time() efficiently. Since
20553dc33bd3SKees Cook		  this makes the mapping executable, it can be used during
20563dc33bd3SKees Cook		  security vulnerability exploitation (traditionally as
20573dc33bd3SKees Cook		  ROP gadgets). This configuration is not recommended.
20583dc33bd3SKees Cook
20593dc33bd3SKees Cook	config LEGACY_VSYSCALL_EMULATE
20603dc33bd3SKees Cook		bool "Emulate"
20613dc33bd3SKees Cook		help
20623dc33bd3SKees Cook		  The kernel traps and emulates calls into the fixed
20633dc33bd3SKees Cook		  vsyscall address mapping. This makes the mapping
20643dc33bd3SKees Cook		  non-executable, but it still contains known contents,
20653dc33bd3SKees Cook		  which could be used in certain rare security vulnerability
20663dc33bd3SKees Cook		  exploits. This configuration is recommended when userspace
20673dc33bd3SKees Cook		  still uses the vsyscall area.
20683dc33bd3SKees Cook
20693dc33bd3SKees Cook	config LEGACY_VSYSCALL_NONE
20703dc33bd3SKees Cook		bool "None"
20713dc33bd3SKees Cook		help
20723dc33bd3SKees Cook		  There will be no vsyscall mapping at all. This will
20733dc33bd3SKees Cook		  eliminate any risk of ASLR bypass due to the vsyscall
20743dc33bd3SKees Cook		  fixed address mapping. Attempts to use the vsyscalls
20753dc33bd3SKees Cook		  will be reported to dmesg, so that either old or
20763dc33bd3SKees Cook		  malicious userspace programs can be identified.
20773dc33bd3SKees Cook
20783dc33bd3SKees Cookendchoice
20793dc33bd3SKees Cook
2080516cbf37STim Birdconfig CMDLINE_BOOL
2081516cbf37STim Bird	bool "Built-in kernel command line"
20828f9ca475SIngo Molnar	---help---
2083516cbf37STim Bird	  Allow for specifying boot arguments to the kernel at
2084516cbf37STim Bird	  build time.  On some systems (e.g. embedded ones), it is
2085516cbf37STim Bird	  necessary or convenient to provide some or all of the
2086516cbf37STim Bird	  kernel boot arguments with the kernel itself (that is,
2087516cbf37STim Bird	  to not rely on the boot loader to provide them.)
2088516cbf37STim Bird
2089516cbf37STim Bird	  To compile command line arguments into the kernel,
2090516cbf37STim Bird	  set this option to 'Y', then fill in the
209169711ca1SSébastien Hinderer	  boot arguments in CONFIG_CMDLINE.
2092516cbf37STim Bird
2093516cbf37STim Bird	  Systems with fully functional boot loaders (i.e. non-embedded)
2094516cbf37STim Bird	  should leave this option set to 'N'.
2095516cbf37STim Bird
2096516cbf37STim Birdconfig CMDLINE
2097516cbf37STim Bird	string "Built-in kernel command string"
2098516cbf37STim Bird	depends on CMDLINE_BOOL
2099516cbf37STim Bird	default ""
21008f9ca475SIngo Molnar	---help---
2101516cbf37STim Bird	  Enter arguments here that should be compiled into the kernel
2102516cbf37STim Bird	  image and used at boot time.  If the boot loader provides a
2103516cbf37STim Bird	  command line at boot time, it is appended to this string to
2104516cbf37STim Bird	  form the full kernel command line, when the system boots.
2105516cbf37STim Bird
2106516cbf37STim Bird	  However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2107516cbf37STim Bird	  change this behavior.
2108516cbf37STim Bird
2109516cbf37STim Bird	  In most cases, the command line (whether built-in or provided
2110516cbf37STim Bird	  by the boot loader) should specify the device for the root
2111516cbf37STim Bird	  file system.
2112516cbf37STim Bird
2113516cbf37STim Birdconfig CMDLINE_OVERRIDE
2114516cbf37STim Bird	bool "Built-in command line overrides boot loader arguments"
2115516cbf37STim Bird	depends on CMDLINE_BOOL
21168f9ca475SIngo Molnar	---help---
2117516cbf37STim Bird	  Set this option to 'Y' to have the kernel ignore the boot loader
2118516cbf37STim Bird	  command line, and use ONLY the built-in command line.
2119516cbf37STim Bird
2120516cbf37STim Bird	  This is used to work around broken boot loaders.  This should
2121516cbf37STim Bird	  be set to 'N' under normal conditions.
2122516cbf37STim Bird
2123a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL
2124a5b9e5a2SAndy Lutomirski	bool "Enable the LDT (local descriptor table)" if EXPERT
2125a5b9e5a2SAndy Lutomirski	default y
2126a5b9e5a2SAndy Lutomirski	---help---
2127a5b9e5a2SAndy Lutomirski	  Linux can allow user programs to install a per-process x86
2128a5b9e5a2SAndy Lutomirski	  Local Descriptor Table (LDT) using the modify_ldt(2) system
2129a5b9e5a2SAndy Lutomirski	  call.  This is required to run 16-bit or segmented code such as
2130a5b9e5a2SAndy Lutomirski	  DOSEMU or some Wine programs.  It is also used by some very old
2131a5b9e5a2SAndy Lutomirski	  threading libraries.
2132a5b9e5a2SAndy Lutomirski
2133a5b9e5a2SAndy Lutomirski	  Enabling this feature adds a small amount of overhead to
2134a5b9e5a2SAndy Lutomirski	  context switches and increases the low-level kernel attack
2135a5b9e5a2SAndy Lutomirski	  surface.  Disabling it removes the modify_ldt(2) system call.
2136a5b9e5a2SAndy Lutomirski
2137a5b9e5a2SAndy Lutomirski	  Saying 'N' here may make sense for embedded or server kernels.
2138a5b9e5a2SAndy Lutomirski
2139b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig"
2140b700e7f0SSeth Jennings
2141506f1d07SSam Ravnborgendmenu
2142506f1d07SSam Ravnborg
2143506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG
2144506f1d07SSam Ravnborg	def_bool y
2145506f1d07SSam Ravnborg	depends on X86_64 || (X86_32 && HIGHMEM)
2146506f1d07SSam Ravnborg
214735551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE
214835551053SGary Hade	def_bool y
214935551053SGary Hade	depends on MEMORY_HOTPLUG
215035551053SGary Hade
2151e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID
2152645a7919STejun Heo	def_bool y
2153e534c7c5SLee Schermerhorn	depends on NUMA
2154e534c7c5SLee Schermerhorn
21559491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK
21569491846fSKirill A. Shutemov	def_bool y
21579491846fSKirill A. Shutemov	depends on X86_64 || X86_PAE
21589491846fSKirill A. Shutemov
2159c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION
2160c177c81eSNaoya Horiguchi	def_bool y
2161c177c81eSNaoya Horiguchi	depends on X86_64 && HUGETLB_PAGE && MIGRATION
2162c177c81eSNaoya Horiguchi
2163da85f865SBjorn Helgaasmenu "Power management and ACPI options"
2164e279b6c1SSam Ravnborg
2165e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER
21663c2362e6SHarvey Harrison	def_bool y
2167e279b6c1SSam Ravnborg	depends on X86_64 && HIBERNATION
2168e279b6c1SSam Ravnborg
2169e279b6c1SSam Ravnborgsource "kernel/power/Kconfig"
2170e279b6c1SSam Ravnborg
2171e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig"
2172e279b6c1SSam Ravnborg
2173efafc8b2SFeng Tangsource "drivers/sfi/Kconfig"
2174efafc8b2SFeng Tang
2175a6b68076SAndi Kleenconfig X86_APM_BOOT
21766fc108a0SJan Beulich	def_bool y
2177282e5aabSPaul Bolle	depends on APM
2178a6b68076SAndi Kleen
2179e279b6c1SSam Ravnborgmenuconfig APM
2180e279b6c1SSam Ravnborg	tristate "APM (Advanced Power Management) BIOS support"
2181efefa6f6SIngo Molnar	depends on X86_32 && PM_SLEEP
2182e279b6c1SSam Ravnborg	---help---
2183e279b6c1SSam Ravnborg	  APM is a BIOS specification for saving power using several different
2184e279b6c1SSam Ravnborg	  techniques. This is mostly useful for battery powered laptops with
2185e279b6c1SSam Ravnborg	  APM compliant BIOSes. If you say Y here, the system time will be
2186e279b6c1SSam Ravnborg	  reset after a RESUME operation, the /proc/apm device will provide
2187e279b6c1SSam Ravnborg	  battery status information, and user-space programs will receive
2188e279b6c1SSam Ravnborg	  notification of APM "events" (e.g. battery status change).
2189e279b6c1SSam Ravnborg
2190e279b6c1SSam Ravnborg	  If you select "Y" here, you can disable actual use of the APM
2191e279b6c1SSam Ravnborg	  BIOS by passing the "apm=off" option to the kernel at boot time.
2192e279b6c1SSam Ravnborg
2193e279b6c1SSam Ravnborg	  Note that the APM support is almost completely disabled for
2194e279b6c1SSam Ravnborg	  machines with more than one CPU.
2195e279b6c1SSam Ravnborg
2196e279b6c1SSam Ravnborg	  In order to use APM, you will need supporting software. For location
21972dc98fd3SMichael Witten	  and more information, read <file:Documentation/power/apm-acpi.txt>
21982dc98fd3SMichael Witten	  and the Battery Powered Linux mini-HOWTO, available from
2199e279b6c1SSam Ravnborg	  <http://www.tldp.org/docs.html#howto>.
2200e279b6c1SSam Ravnborg
2201e279b6c1SSam Ravnborg	  This driver does not spin down disk drives (see the hdparm(8)
2202e279b6c1SSam Ravnborg	  manpage ("man 8 hdparm") for that), and it doesn't turn off
2203e279b6c1SSam Ravnborg	  VESA-compliant "green" monitors.
2204e279b6c1SSam Ravnborg
2205e279b6c1SSam Ravnborg	  This driver does not support the TI 4000M TravelMate and the ACER
2206e279b6c1SSam Ravnborg	  486/DX4/75 because they don't have compliant BIOSes. Many "green"
2207e279b6c1SSam Ravnborg	  desktop machines also don't have compliant BIOSes, and this driver
2208e279b6c1SSam Ravnborg	  may cause those machines to panic during the boot phase.
2209e279b6c1SSam Ravnborg
2210e279b6c1SSam Ravnborg	  Generally, if you don't have a battery in your machine, there isn't
2211e279b6c1SSam Ravnborg	  much point in using this driver and you should say N. If you get
2212e279b6c1SSam Ravnborg	  random kernel OOPSes or reboots that don't seem to be related to
2213e279b6c1SSam Ravnborg	  anything, try disabling/enabling this option (or disabling/enabling
2214e279b6c1SSam Ravnborg	  APM in your BIOS).
2215e279b6c1SSam Ravnborg
2216e279b6c1SSam Ravnborg	  Some other things you should try when experiencing seemingly random,
2217e279b6c1SSam Ravnborg	  "weird" problems:
2218e279b6c1SSam Ravnborg
2219e279b6c1SSam Ravnborg	  1) make sure that you have enough swap space and that it is
2220e279b6c1SSam Ravnborg	  enabled.
2221e279b6c1SSam Ravnborg	  2) pass the "no-hlt" option to the kernel
2222e279b6c1SSam Ravnborg	  3) switch on floating point emulation in the kernel and pass
2223e279b6c1SSam Ravnborg	  the "no387" option to the kernel
2224e279b6c1SSam Ravnborg	  4) pass the "floppy=nodma" option to the kernel
2225e279b6c1SSam Ravnborg	  5) pass the "mem=4M" option to the kernel (thereby disabling
2226e279b6c1SSam Ravnborg	  all but the first 4 MB of RAM)
2227e279b6c1SSam Ravnborg	  6) make sure that the CPU is not over clocked.
2228e279b6c1SSam Ravnborg	  7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2229e279b6c1SSam Ravnborg	  8) disable the cache from your BIOS settings
2230e279b6c1SSam Ravnborg	  9) install a fan for the video card or exchange video RAM
2231e279b6c1SSam Ravnborg	  10) install a better fan for the CPU
2232e279b6c1SSam Ravnborg	  11) exchange RAM chips
2233e279b6c1SSam Ravnborg	  12) exchange the motherboard.
2234e279b6c1SSam Ravnborg
2235e279b6c1SSam Ravnborg	  To compile this driver as a module, choose M here: the
2236e279b6c1SSam Ravnborg	  module will be called apm.
2237e279b6c1SSam Ravnborg
2238e279b6c1SSam Ravnborgif APM
2239e279b6c1SSam Ravnborg
2240e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND
2241e279b6c1SSam Ravnborg	bool "Ignore USER SUSPEND"
22428f9ca475SIngo Molnar	---help---
2243e279b6c1SSam Ravnborg	  This option will ignore USER SUSPEND requests. On machines with a
2244e279b6c1SSam Ravnborg	  compliant APM BIOS, you want to say N. However, on the NEC Versa M
2245e279b6c1SSam Ravnborg	  series notebooks, it is necessary to say Y because of a BIOS bug.
2246e279b6c1SSam Ravnborg
2247e279b6c1SSam Ravnborgconfig APM_DO_ENABLE
2248e279b6c1SSam Ravnborg	bool "Enable PM at boot time"
2249e279b6c1SSam Ravnborg	---help---
2250e279b6c1SSam Ravnborg	  Enable APM features at boot time. From page 36 of the APM BIOS
2251e279b6c1SSam Ravnborg	  specification: "When disabled, the APM BIOS does not automatically
2252e279b6c1SSam Ravnborg	  power manage devices, enter the Standby State, enter the Suspend
2253e279b6c1SSam Ravnborg	  State, or take power saving steps in response to CPU Idle calls."
2254e279b6c1SSam Ravnborg	  This driver will make CPU Idle calls when Linux is idle (unless this
2255e279b6c1SSam Ravnborg	  feature is turned off -- see "Do CPU IDLE calls", below). This
2256e279b6c1SSam Ravnborg	  should always save battery power, but more complicated APM features
2257e279b6c1SSam Ravnborg	  will be dependent on your BIOS implementation. You may need to turn
2258e279b6c1SSam Ravnborg	  this option off if your computer hangs at boot time when using APM
2259e279b6c1SSam Ravnborg	  support, or if it beeps continuously instead of suspending. Turn
2260e279b6c1SSam Ravnborg	  this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2261e279b6c1SSam Ravnborg	  T400CDT. This is off by default since most machines do fine without
2262e279b6c1SSam Ravnborg	  this feature.
2263e279b6c1SSam Ravnborg
2264e279b6c1SSam Ravnborgconfig APM_CPU_IDLE
2265dd8af076SLen Brown	depends on CPU_IDLE
2266e279b6c1SSam Ravnborg	bool "Make CPU Idle calls when idle"
22678f9ca475SIngo Molnar	---help---
2268e279b6c1SSam Ravnborg	  Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2269e279b6c1SSam Ravnborg	  On some machines, this can activate improved power savings, such as
2270e279b6c1SSam Ravnborg	  a slowed CPU clock rate, when the machine is idle. These idle calls
2271e279b6c1SSam Ravnborg	  are made after the idle loop has run for some length of time (e.g.,
2272e279b6c1SSam Ravnborg	  333 mS). On some machines, this will cause a hang at boot time or
2273e279b6c1SSam Ravnborg	  whenever the CPU becomes idle. (On machines with more than one CPU,
2274e279b6c1SSam Ravnborg	  this option does nothing.)
2275e279b6c1SSam Ravnborg
2276e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK
2277e279b6c1SSam Ravnborg	bool "Enable console blanking using APM"
22788f9ca475SIngo Molnar	---help---
2279e279b6c1SSam Ravnborg	  Enable console blanking using the APM. Some laptops can use this to
2280e279b6c1SSam Ravnborg	  turn off the LCD backlight when the screen blanker of the Linux
2281e279b6c1SSam Ravnborg	  virtual console blanks the screen. Note that this is only used by
2282e279b6c1SSam Ravnborg	  the virtual console screen blanker, and won't turn off the backlight
2283e279b6c1SSam Ravnborg	  when using the X Window system. This also doesn't have anything to
2284e279b6c1SSam Ravnborg	  do with your VESA-compliant power-saving monitor. Further, this
2285e279b6c1SSam Ravnborg	  option doesn't work for all laptops -- it might not turn off your
2286e279b6c1SSam Ravnborg	  backlight at all, or it might print a lot of errors to the console,
2287e279b6c1SSam Ravnborg	  especially if you are using gpm.
2288e279b6c1SSam Ravnborg
2289e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS
2290e279b6c1SSam Ravnborg	bool "Allow interrupts during APM BIOS calls"
22918f9ca475SIngo Molnar	---help---
2292e279b6c1SSam Ravnborg	  Normally we disable external interrupts while we are making calls to
2293e279b6c1SSam Ravnborg	  the APM BIOS as a measure to lessen the effects of a badly behaving
2294e279b6c1SSam Ravnborg	  BIOS implementation.  The BIOS should reenable interrupts if it
2295e279b6c1SSam Ravnborg	  needs to.  Unfortunately, some BIOSes do not -- especially those in
2296e279b6c1SSam Ravnborg	  many of the newer IBM Thinkpads.  If you experience hangs when you
2297e279b6c1SSam Ravnborg	  suspend, try setting this to Y.  Otherwise, say N.
2298e279b6c1SSam Ravnborg
2299e279b6c1SSam Ravnborgendif # APM
2300e279b6c1SSam Ravnborg
2301bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig"
2302e279b6c1SSam Ravnborg
2303e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig"
2304e279b6c1SSam Ravnborg
230527471fdbSAndy Henroidsource "drivers/idle/Kconfig"
230627471fdbSAndy Henroid
2307e279b6c1SSam Ravnborgendmenu
2308e279b6c1SSam Ravnborg
2309e279b6c1SSam Ravnborg
2310e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)"
2311e279b6c1SSam Ravnborg
2312e279b6c1SSam Ravnborgconfig PCI
23131ac97018SIngo Molnar	bool "PCI support"
23141c858087SAdrian Bunk	default y
23158f9ca475SIngo Molnar	---help---
2316e279b6c1SSam Ravnborg	  Find out whether you have a PCI motherboard. PCI is the name of a
2317e279b6c1SSam Ravnborg	  bus system, i.e. the way the CPU talks to the other stuff inside
2318e279b6c1SSam Ravnborg	  your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2319e279b6c1SSam Ravnborg	  VESA. If you have PCI, say Y, otherwise N.
2320e279b6c1SSam Ravnborg
2321e279b6c1SSam Ravnborgchoice
2322e279b6c1SSam Ravnborg	prompt "PCI access mode"
2323efefa6f6SIngo Molnar	depends on X86_32 && PCI
2324e279b6c1SSam Ravnborg	default PCI_GOANY
2325e279b6c1SSam Ravnborg	---help---
2326e279b6c1SSam Ravnborg	  On PCI systems, the BIOS can be used to detect the PCI devices and
2327e279b6c1SSam Ravnborg	  determine their configuration. However, some old PCI motherboards
2328e279b6c1SSam Ravnborg	  have BIOS bugs and may crash if this is done. Also, some embedded
2329e279b6c1SSam Ravnborg	  PCI-based systems don't have any BIOS at all. Linux can also try to
2330e279b6c1SSam Ravnborg	  detect the PCI hardware directly without using the BIOS.
2331e279b6c1SSam Ravnborg
2332e279b6c1SSam Ravnborg	  With this option, you can specify how Linux should detect the
2333e279b6c1SSam Ravnborg	  PCI devices. If you choose "BIOS", the BIOS will be used,
2334e279b6c1SSam Ravnborg	  if you choose "Direct", the BIOS won't be used, and if you
2335e279b6c1SSam Ravnborg	  choose "MMConfig", then PCI Express MMCONFIG will be used.
2336e279b6c1SSam Ravnborg	  If you choose "Any", the kernel will try MMCONFIG, then the
2337e279b6c1SSam Ravnborg	  direct access method and falls back to the BIOS if that doesn't
2338e279b6c1SSam Ravnborg	  work. If unsure, go with the default, which is "Any".
2339e279b6c1SSam Ravnborg
2340e279b6c1SSam Ravnborgconfig PCI_GOBIOS
2341e279b6c1SSam Ravnborg	bool "BIOS"
2342e279b6c1SSam Ravnborg
2343e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG
2344e279b6c1SSam Ravnborg	bool "MMConfig"
2345e279b6c1SSam Ravnborg
2346e279b6c1SSam Ravnborgconfig PCI_GODIRECT
2347e279b6c1SSam Ravnborg	bool "Direct"
2348e279b6c1SSam Ravnborg
23493ef0e1f8SAndres Salomonconfig PCI_GOOLPC
235076fb6570SDaniel Drake	bool "OLPC XO-1"
23513ef0e1f8SAndres Salomon	depends on OLPC
23523ef0e1f8SAndres Salomon
23532bdd1b03SAndres Salomonconfig PCI_GOANY
23542bdd1b03SAndres Salomon	bool "Any"
23552bdd1b03SAndres Salomon
2356e279b6c1SSam Ravnborgendchoice
2357e279b6c1SSam Ravnborg
2358e279b6c1SSam Ravnborgconfig PCI_BIOS
23593c2362e6SHarvey Harrison	def_bool y
2360efefa6f6SIngo Molnar	depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2361e279b6c1SSam Ravnborg
2362e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2363e279b6c1SSam Ravnborgconfig PCI_DIRECT
23643c2362e6SHarvey Harrison	def_bool y
23650aba496fSShaohua Li	depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2366e279b6c1SSam Ravnborg
2367e279b6c1SSam Ravnborgconfig PCI_MMCONFIG
23683c2362e6SHarvey Harrison	def_bool y
23695f0db7a2SFeng Tang	depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2370e279b6c1SSam Ravnborg
23713ef0e1f8SAndres Salomonconfig PCI_OLPC
23722bdd1b03SAndres Salomon	def_bool y
23732bdd1b03SAndres Salomon	depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
23743ef0e1f8SAndres Salomon
2375b5401a96SAlex Nixonconfig PCI_XEN
2376b5401a96SAlex Nixon	def_bool y
2377b5401a96SAlex Nixon	depends on PCI && XEN
2378b5401a96SAlex Nixon	select SWIOTLB_XEN
2379b5401a96SAlex Nixon
2380e279b6c1SSam Ravnborgconfig PCI_DOMAINS
23813c2362e6SHarvey Harrison	def_bool y
2382e279b6c1SSam Ravnborg	depends on PCI
2383e279b6c1SSam Ravnborg
2384e279b6c1SSam Ravnborgconfig PCI_MMCONFIG
2385e279b6c1SSam Ravnborg	bool "Support mmconfig PCI config space access"
2386e279b6c1SSam Ravnborg	depends on X86_64 && PCI && ACPI
2387e279b6c1SSam Ravnborg
23883f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK
23896a108a14SDavid Rientjes	bool "Read CNB20LE Host Bridge Windows" if EXPERT
23906ea30386SKees Cook	depends on PCI
23913f6ea84aSIra W. Snyder	help
23923f6ea84aSIra W. Snyder	  Read the PCI windows out of the CNB20LE host bridge. This allows
23933f6ea84aSIra W. Snyder	  PCI hotplug to work on systems with the CNB20LE chipset which do
23943f6ea84aSIra W. Snyder	  not have ACPI.
23953f6ea84aSIra W. Snyder
239664a5fed6SBjorn Helgaas	  There's no public spec for this chipset, and this functionality
239764a5fed6SBjorn Helgaas	  is known to be incomplete.
239864a5fed6SBjorn Helgaas
239964a5fed6SBjorn Helgaas	  You should say N unless you know you need this.
240064a5fed6SBjorn Helgaas
2401e279b6c1SSam Ravnborgsource "drivers/pci/pcie/Kconfig"
2402e279b6c1SSam Ravnborg
2403e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig"
2404e279b6c1SSam Ravnborg
24051c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA.
2406e279b6c1SSam Ravnborgconfig ISA_DMA_API
24071c00f016SDavid Rientjes	bool "ISA-style DMA support" if (X86_64 && EXPERT)
24081c00f016SDavid Rientjes	default y
24091c00f016SDavid Rientjes	help
24101c00f016SDavid Rientjes	  Enables ISA-style DMA support for devices requiring such controllers.
24111c00f016SDavid Rientjes	  If unsure, say Y.
2412e279b6c1SSam Ravnborg
2413e279b6c1SSam Ravnborgif X86_32
2414e279b6c1SSam Ravnborg
2415e279b6c1SSam Ravnborgconfig ISA
2416e279b6c1SSam Ravnborg	bool "ISA support"
24178f9ca475SIngo Molnar	---help---
2418e279b6c1SSam Ravnborg	  Find out whether you have ISA slots on your motherboard.  ISA is the
2419e279b6c1SSam Ravnborg	  name of a bus system, i.e. the way the CPU talks to the other stuff
2420e279b6c1SSam Ravnborg	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
2421e279b6c1SSam Ravnborg	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2422e279b6c1SSam Ravnborg	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
2423e279b6c1SSam Ravnborg
2424e279b6c1SSam Ravnborgconfig EISA
2425e279b6c1SSam Ravnborg	bool "EISA support"
2426e279b6c1SSam Ravnborg	depends on ISA
2427e279b6c1SSam Ravnborg	---help---
2428e279b6c1SSam Ravnborg	  The Extended Industry Standard Architecture (EISA) bus was
2429e279b6c1SSam Ravnborg	  developed as an open alternative to the IBM MicroChannel bus.
2430e279b6c1SSam Ravnborg
2431e279b6c1SSam Ravnborg	  The EISA bus provided some of the features of the IBM MicroChannel
2432e279b6c1SSam Ravnborg	  bus while maintaining backward compatibility with cards made for
2433e279b6c1SSam Ravnborg	  the older ISA bus.  The EISA bus saw limited use between 1988 and
2434e279b6c1SSam Ravnborg	  1995 when it was made obsolete by the PCI bus.
2435e279b6c1SSam Ravnborg
2436e279b6c1SSam Ravnborg	  Say Y here if you are building a kernel for an EISA-based machine.
2437e279b6c1SSam Ravnborg
2438e279b6c1SSam Ravnborg	  Otherwise, say N.
2439e279b6c1SSam Ravnborg
2440e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig"
2441e279b6c1SSam Ravnborg
2442e279b6c1SSam Ravnborgconfig SCx200
2443e279b6c1SSam Ravnborg	tristate "NatSemi SCx200 support"
24448f9ca475SIngo Molnar	---help---
2445e279b6c1SSam Ravnborg	  This provides basic support for National Semiconductor's
2446e279b6c1SSam Ravnborg	  (now AMD's) Geode processors.  The driver probes for the
2447e279b6c1SSam Ravnborg	  PCI-IDs of several on-chip devices, so its a good dependency
2448e279b6c1SSam Ravnborg	  for other scx200_* drivers.
2449e279b6c1SSam Ravnborg
2450e279b6c1SSam Ravnborg	  If compiled as a module, the driver is named scx200.
2451e279b6c1SSam Ravnborg
2452e279b6c1SSam Ravnborgconfig SCx200HR_TIMER
2453e279b6c1SSam Ravnborg	tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2454592913ecSJohn Stultz	depends on SCx200
2455e279b6c1SSam Ravnborg	default y
24568f9ca475SIngo Molnar	---help---
2457e279b6c1SSam Ravnborg	  This driver provides a clocksource built upon the on-chip
2458e279b6c1SSam Ravnborg	  27MHz high-resolution timer.  Its also a workaround for
2459e279b6c1SSam Ravnborg	  NSC Geode SC-1100's buggy TSC, which loses time when the
2460e279b6c1SSam Ravnborg	  processor goes idle (as is done by the scheduler).  The
2461e279b6c1SSam Ravnborg	  other workaround is idle=poll boot option.
2462e279b6c1SSam Ravnborg
24633ef0e1f8SAndres Salomonconfig OLPC
24643ef0e1f8SAndres Salomon	bool "One Laptop Per Child support"
246554008979SThomas Gleixner	depends on !X86_PAE
24663c554946SAndres Salomon	select GPIOLIB
2467dc3119e7SThomas Gleixner	select OF
246845bb1674SDaniel Drake	select OF_PROMTREE
2469b4e51854SGrant Likely	select IRQ_DOMAIN
24708f9ca475SIngo Molnar	---help---
24713ef0e1f8SAndres Salomon	  Add support for detecting the unique features of the OLPC
24723ef0e1f8SAndres Salomon	  XO hardware.
24733ef0e1f8SAndres Salomon
2474a3128588SDaniel Drakeconfig OLPC_XO1_PM
2475a3128588SDaniel Drake	bool "OLPC XO-1 Power Management"
247697c4cb71SDaniel Drake	depends on OLPC && MFD_CS5535 && PM_SLEEP
2477a3128588SDaniel Drake	select MFD_CORE
2478bf1ebf00SDaniel Drake	---help---
247997c4cb71SDaniel Drake	  Add support for poweroff and suspend of the OLPC XO-1 laptop.
2480bf1ebf00SDaniel Drake
2481cfee9597SDaniel Drakeconfig OLPC_XO1_RTC
2482cfee9597SDaniel Drake	bool "OLPC XO-1 Real Time Clock"
2483cfee9597SDaniel Drake	depends on OLPC_XO1_PM && RTC_DRV_CMOS
2484cfee9597SDaniel Drake	---help---
2485cfee9597SDaniel Drake	  Add support for the XO-1 real time clock, which can be used as a
2486cfee9597SDaniel Drake	  programmable wakeup source.
2487cfee9597SDaniel Drake
24887feda8e9SDaniel Drakeconfig OLPC_XO1_SCI
24897feda8e9SDaniel Drake	bool "OLPC XO-1 SCI extras"
2490d8d01a63SDaniel Drake	depends on OLPC && OLPC_XO1_PM
2491ed8e47feSRandy Dunlap	depends on INPUT=y
2492d8d01a63SDaniel Drake	select POWER_SUPPLY
24937feda8e9SDaniel Drake	select GPIO_CS5535
24947feda8e9SDaniel Drake	select MFD_CORE
24957feda8e9SDaniel Drake	---help---
24967feda8e9SDaniel Drake	  Add support for SCI-based features of the OLPC XO-1 laptop:
24977bc74b3dSDaniel Drake	   - EC-driven system wakeups
24987feda8e9SDaniel Drake	   - Power button
24997bc74b3dSDaniel Drake	   - Ebook switch
25002cf2baeaSDaniel Drake	   - Lid switch
2501e1040ac6SDaniel Drake	   - AC adapter status updates
2502e1040ac6SDaniel Drake	   - Battery status updates
25037feda8e9SDaniel Drake
2504a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI
2505a0f30f59SDaniel Drake	bool "OLPC XO-1.5 SCI extras"
2506d8d01a63SDaniel Drake	depends on OLPC && ACPI
2507d8d01a63SDaniel Drake	select POWER_SUPPLY
2508a0f30f59SDaniel Drake	---help---
2509a0f30f59SDaniel Drake	  Add support for SCI-based features of the OLPC XO-1.5 laptop:
2510a0f30f59SDaniel Drake	   - EC-driven system wakeups
2511a0f30f59SDaniel Drake	   - AC adapter status updates
2512a0f30f59SDaniel Drake	   - Battery status updates
2513e279b6c1SSam Ravnborg
2514d4f3e350SEd Wildgooseconfig ALIX
2515d4f3e350SEd Wildgoose	bool "PCEngines ALIX System Support (LED setup)"
2516d4f3e350SEd Wildgoose	select GPIOLIB
2517d4f3e350SEd Wildgoose	---help---
2518d4f3e350SEd Wildgoose	  This option enables system support for the PCEngines ALIX.
2519d4f3e350SEd Wildgoose	  At present this just sets up LEDs for GPIO control on
2520d4f3e350SEd Wildgoose	  ALIX2/3/6 boards.  However, other system specific setup should
2521d4f3e350SEd Wildgoose	  get added here.
2522d4f3e350SEd Wildgoose
2523d4f3e350SEd Wildgoose	  Note: You must still enable the drivers for GPIO and LED support
2524d4f3e350SEd Wildgoose	  (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2525d4f3e350SEd Wildgoose
2526d4f3e350SEd Wildgoose	  Note: You have to set alix.force=1 for boards with Award BIOS.
2527d4f3e350SEd Wildgoose
2528da4e3302SPhilip Prindevilleconfig NET5501
2529da4e3302SPhilip Prindeville	bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2530da4e3302SPhilip Prindeville	select GPIOLIB
2531da4e3302SPhilip Prindeville	---help---
2532da4e3302SPhilip Prindeville	  This option enables system support for the Soekris Engineering net5501.
2533da4e3302SPhilip Prindeville
25343197059aSPhilip A. Prindevilleconfig GEOS
25353197059aSPhilip A. Prindeville	bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
25363197059aSPhilip A. Prindeville	select GPIOLIB
25373197059aSPhilip A. Prindeville	depends on DMI
25383197059aSPhilip A. Prindeville	---help---
25393197059aSPhilip A. Prindeville	  This option enables system support for the Traverse Technologies GEOS.
25403197059aSPhilip A. Prindeville
25417d029125SVivien Didelotconfig TS5500
25427d029125SVivien Didelot	bool "Technologic Systems TS-5500 platform support"
25437d029125SVivien Didelot	depends on MELAN
25447d029125SVivien Didelot	select CHECK_SIGNATURE
25457d029125SVivien Didelot	select NEW_LEDS
25467d029125SVivien Didelot	select LEDS_CLASS
25477d029125SVivien Didelot	---help---
25487d029125SVivien Didelot	  This option enables system support for the Technologic Systems TS-5500.
25497d029125SVivien Didelot
2550e279b6c1SSam Ravnborgendif # X86_32
2551e279b6c1SSam Ravnborg
255223ac4ae8SAndreas Herrmannconfig AMD_NB
2553e279b6c1SSam Ravnborg	def_bool y
25540e152cd7SBorislav Petkov	depends on CPU_SUP_AMD && PCI
2555e279b6c1SSam Ravnborg
2556e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig"
2557e279b6c1SSam Ravnborg
2558e279b6c1SSam Ravnborgsource "drivers/pci/hotplug/Kconfig"
2559e279b6c1SSam Ravnborg
2560388b78adSAlexandre Bounineconfig RAPIDIO
2561fdf90abcSAlexandre Bounine	tristate "RapidIO support"
2562388b78adSAlexandre Bounine	depends on PCI
2563388b78adSAlexandre Bounine	default n
2564388b78adSAlexandre Bounine	help
2565fdf90abcSAlexandre Bounine	  If enabled this option will include drivers and the core
2566388b78adSAlexandre Bounine	  infrastructure code to support RapidIO interconnect devices.
2567388b78adSAlexandre Bounine
2568388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig"
2569388b78adSAlexandre Bounine
2570e3263ab3SDavid Herrmannconfig X86_SYSFB
2571e3263ab3SDavid Herrmann	bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2572e3263ab3SDavid Herrmann	help
2573e3263ab3SDavid Herrmann	  Firmwares often provide initial graphics framebuffers so the BIOS,
2574e3263ab3SDavid Herrmann	  bootloader or kernel can show basic video-output during boot for
2575e3263ab3SDavid Herrmann	  user-guidance and debugging. Historically, x86 used the VESA BIOS
2576e3263ab3SDavid Herrmann	  Extensions and EFI-framebuffers for this, which are mostly limited
2577e3263ab3SDavid Herrmann	  to x86.
2578e3263ab3SDavid Herrmann	  This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2579e3263ab3SDavid Herrmann	  framebuffers so the new generic system-framebuffer drivers can be
2580e3263ab3SDavid Herrmann	  used on x86. If the framebuffer is not compatible with the generic
2581e3263ab3SDavid Herrmann	  modes, it is adverticed as fallback platform framebuffer so legacy
2582e3263ab3SDavid Herrmann	  drivers like efifb, vesafb and uvesafb can pick it up.
2583e3263ab3SDavid Herrmann	  If this option is not selected, all system framebuffers are always
2584e3263ab3SDavid Herrmann	  marked as fallback platform framebuffers as usual.
2585e3263ab3SDavid Herrmann
2586e3263ab3SDavid Herrmann	  Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2587e3263ab3SDavid Herrmann	  not be able to pick up generic system framebuffers if this option
2588e3263ab3SDavid Herrmann	  is selected. You are highly encouraged to enable simplefb as
2589e3263ab3SDavid Herrmann	  replacement if you select this option. simplefb can correctly deal
2590e3263ab3SDavid Herrmann	  with generic system framebuffers. But you should still keep vesafb
2591e3263ab3SDavid Herrmann	  and others enabled as fallback if a system framebuffer is
2592e3263ab3SDavid Herrmann	  incompatible with simplefb.
2593e3263ab3SDavid Herrmann
2594e3263ab3SDavid Herrmann	  If unsure, say Y.
2595e3263ab3SDavid Herrmann
2596e279b6c1SSam Ravnborgendmenu
2597e279b6c1SSam Ravnborg
2598e279b6c1SSam Ravnborg
2599e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations"
2600e279b6c1SSam Ravnborg
2601e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt"
2602e279b6c1SSam Ravnborg
2603e279b6c1SSam Ravnborgconfig IA32_EMULATION
2604e279b6c1SSam Ravnborg	bool "IA32 Emulation"
2605e279b6c1SSam Ravnborg	depends on X86_64
2606d1603990SRandy Dunlap	select BINFMT_ELF
2607a97f52e6SRoland McGrath	select COMPAT_BINFMT_ELF
26083bead553SBrian Gerst	select ARCH_WANT_OLD_COMPAT_IPC
26098f9ca475SIngo Molnar	---help---
26105fd92e65SH. J. Lu	  Include code to run legacy 32-bit programs under a
26115fd92e65SH. J. Lu	  64-bit kernel. You should likely turn this on, unless you're
26125fd92e65SH. J. Lu	  100% sure that you don't have any 32-bit programs left.
2613e279b6c1SSam Ravnborg
2614e279b6c1SSam Ravnborgconfig IA32_AOUT
2615e279b6c1SSam Ravnborg	tristate "IA32 a.out support"
26166b213e1bSDavid Woodhouse	depends on IA32_EMULATION
26178f9ca475SIngo Molnar	---help---
2618e279b6c1SSam Ravnborg	  Support old a.out binaries in the 32bit emulation.
2619e279b6c1SSam Ravnborg
26200bf62763SH. Peter Anvinconfig X86_X32
26216ea30386SKees Cook	bool "x32 ABI for 64-bit mode"
26229b54050bSBrian Gerst	depends on X86_64
26235fd92e65SH. J. Lu	---help---
26245fd92e65SH. J. Lu	  Include code to run binaries for the x32 native 32-bit ABI
26255fd92e65SH. J. Lu	  for 64-bit processors.  An x32 process gets access to the
26265fd92e65SH. J. Lu	  full 64-bit register file and wide data path while leaving
26275fd92e65SH. J. Lu	  pointers at 32 bits for smaller memory footprint.
26285fd92e65SH. J. Lu
26295fd92e65SH. J. Lu	  You will need a recent binutils (2.22 or later) with
26305fd92e65SH. J. Lu	  elf32_x86_64 support enabled to compile a kernel with this
26315fd92e65SH. J. Lu	  option set.
26325fd92e65SH. J. Lu
2633e279b6c1SSam Ravnborgconfig COMPAT
26343c2362e6SHarvey Harrison	def_bool y
26350bf62763SH. Peter Anvin	depends on IA32_EMULATION || X86_X32
2636e279b6c1SSam Ravnborg
26373120e25eSJan Beulichif COMPAT
2638e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT
26393120e25eSJan Beulich	def_bool y
2640e279b6c1SSam Ravnborg
2641e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT
26423c2362e6SHarvey Harrison	def_bool y
26433120e25eSJan Beulich	depends on SYSVIPC
2644e279b6c1SSam Ravnborg
2645ee009e4aSDavid Howellsconfig KEYS_COMPAT
26463120e25eSJan Beulich	def_bool y
26473120e25eSJan Beulich	depends on KEYS
26483120e25eSJan Beulichendif
2649ee009e4aSDavid Howells
2650e279b6c1SSam Ravnborgendmenu
2651e279b6c1SSam Ravnborg
2652e279b6c1SSam Ravnborg
2653e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP
2654e5beae16SKeith Packard	def_bool y
2655e5beae16SKeith Packard	depends on X86_32
2656e5beae16SKeith Packard
26574692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS
26584692d77fSAlessandro Rubini	bool
265983125a3aSAlessandro Rubini	depends on X86_64 || STA2X11
26604692d77fSAlessandro Rubini
2661f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP
2662f7219a53SAlessandro Rubini	bool
266383125a3aSAlessandro Rubini	depends on STA2X11
2664f7219a53SAlessandro Rubini
266593e5eaddSLi, Aubreyconfig PMC_ATOM
266693e5eaddSLi, Aubrey	def_bool y
266793e5eaddSLi, Aubrey        depends on PCI
266893e5eaddSLi, Aubrey
2669e279b6c1SSam Ravnborgsource "net/Kconfig"
2670e279b6c1SSam Ravnborg
2671e279b6c1SSam Ravnborgsource "drivers/Kconfig"
2672e279b6c1SSam Ravnborg
2673e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig"
2674e279b6c1SSam Ravnborg
2675e279b6c1SSam Ravnborgsource "fs/Kconfig"
2676e279b6c1SSam Ravnborg
2677e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug"
2678e279b6c1SSam Ravnborg
2679e279b6c1SSam Ravnborgsource "security/Kconfig"
2680e279b6c1SSam Ravnborg
2681e279b6c1SSam Ravnborgsource "crypto/Kconfig"
2682e279b6c1SSam Ravnborg
2683edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig"
2684edf88417SAvi Kivity
2685e279b6c1SSam Ravnborgsource "lib/Kconfig"
2686