xref: /linux/arch/x86/Kconfig (revision c763ea2650dfa7e95562177f20f0394dce7d6aa9)
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
12341c787eSIngo Molnar	# Options that are inherently 32-bit kernel only:
13341c787eSIngo Molnar	select ARCH_WANT_IPC_PARSE_VERSION
14341c787eSIngo Molnar	select CLKSRC_I8253
15341c787eSIngo Molnar	select CLONE_BACKWARDS
16341c787eSIngo Molnar	select HAVE_AOUT
17341c787eSIngo Molnar	select HAVE_GENERIC_DMA_COHERENT
18341c787eSIngo Molnar	select MODULES_USE_ELF_REL
19341c787eSIngo Molnar	select OLD_SIGACTION
20daa93fabSSam Ravnborg
21daa93fabSSam Ravnborgconfig X86_64
223120e25eSJan Beulich	def_bool y
233120e25eSJan Beulich	depends on 64BIT
24d94e0685SIngo Molnar	# Options that are inherently 64-bit kernel only:
25d94e0685SIngo Molnar	select ARCH_HAS_GIGANTIC_PAGE
26d94e0685SIngo Molnar	select ARCH_SUPPORTS_INT128
27d94e0685SIngo Molnar	select ARCH_USE_CMPXCHG_LOCKREF
28d94e0685SIngo Molnar	select HAVE_ARCH_SOFT_DIRTY
29d94e0685SIngo Molnar	select MODULES_USE_ELF_RELA
30d94e0685SIngo Molnar	select X86_DEV_DMA_OPS
311032c0baSSam Ravnborg
32d94e0685SIngo Molnar#
33d94e0685SIngo Molnar# Arch settings
34d94e0685SIngo Molnar#
35d94e0685SIngo Molnar# ( Note that options that are marked 'if X86_64' could in principle be
36d94e0685SIngo Molnar#   ported to 32-bit as well. )
37d94e0685SIngo Molnar#
388d5fffb9SSam Ravnborgconfig X86
393c2362e6SHarvey Harrison	def_bool y
40*c763ea26SIngo Molnar	#
41*c763ea26SIngo Molnar	# Note: keep this list sorted alphabetically
42*c763ea26SIngo Molnar	#
436471b825SIngo Molnar	select ACPI_LEGACY_TABLES_LOOKUP	if ACPI
446e0a0ea1SGraeme Gregory	select ACPI_SYSTEM_POWER_STATES_SUPPORT	if ACPI
456471b825SIngo Molnar	select ANON_INODES
466471b825SIngo Molnar	select ARCH_CLOCKSOURCE_DATA
476471b825SIngo Molnar	select ARCH_DISCARD_MEMBLOCK
4891dda51aSAleksey Makarov	select ARCH_HAS_ACPI_TABLE_UPGRADE	if ACPI
4921266be9SDan Williams	select ARCH_HAS_DEVMEM_IS_ALLOWED
506471b825SIngo Molnar	select ARCH_HAS_ELF_RANDOMIZE
5172d93104SLinus Torvalds	select ARCH_HAS_FAST_MULTIPLIER
52957e3facSRiku Voipio	select ARCH_HAS_GCOV_PROFILE_ALL
535c9a8750SDmitry Vyukov	select ARCH_HAS_KCOV			if X86_64
5467a3e8feSRoss Zwisler	select ARCH_HAS_MMIO_FLUSH
55*c763ea26SIngo Molnar	select ARCH_HAS_PMEM_API		if X86_64
566471b825SIngo Molnar	select ARCH_HAS_SG_CHAIN
57c6d30853SAndrey Ryabinin	select ARCH_HAS_UBSAN_SANITIZE_ALL
586471b825SIngo Molnar	select ARCH_HAVE_NMI_SAFE_CMPXCHG
596471b825SIngo Molnar	select ARCH_MIGHT_HAVE_ACPI_PDC		if ACPI
6077fbbc81SMark Salter	select ARCH_MIGHT_HAVE_PC_PARPORT
615e2c18c0SMark Salter	select ARCH_MIGHT_HAVE_PC_SERIO
626471b825SIngo Molnar	select ARCH_SUPPORTS_ATOMIC_RMW
633b242c66SMel Gorman	select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
646471b825SIngo Molnar	select ARCH_SUPPORTS_NUMA_BALANCING	if X86_64
656471b825SIngo Molnar	select ARCH_USE_BUILTIN_BSWAP
666471b825SIngo Molnar	select ARCH_USE_QUEUED_RWLOCKS
676471b825SIngo Molnar	select ARCH_USE_QUEUED_SPINLOCKS
6872b252aeSMel Gorman	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP
69da4276b8SIngo Molnar	select ARCH_WANT_FRAME_POINTERS
70*c763ea26SIngo Molnar	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
716471b825SIngo Molnar	select BUILDTIME_EXTABLE_SORT
726471b825SIngo Molnar	select CLKEVT_I8253
736471b825SIngo Molnar	select CLOCKSOURCE_VALIDATE_LAST_CYCLE
746471b825SIngo Molnar	select CLOCKSOURCE_WATCHDOG
756471b825SIngo Molnar	select DCACHE_WORD_ACCESS
7645471cd9SLinus Torvalds	select EDAC_ATOMIC_SCRUB
7745471cd9SLinus Torvalds	select EDAC_SUPPORT
786471b825SIngo Molnar	select GENERIC_CLOCKEVENTS
796471b825SIngo Molnar	select GENERIC_CLOCKEVENTS_BROADCAST	if X86_64 || (X86_32 && X86_LOCAL_APIC)
806471b825SIngo Molnar	select GENERIC_CLOCKEVENTS_MIN_ADJUST
816471b825SIngo Molnar	select GENERIC_CMOS_UPDATE
826471b825SIngo Molnar	select GENERIC_CPU_AUTOPROBE
836471b825SIngo Molnar	select GENERIC_EARLY_IOREMAP
846471b825SIngo Molnar	select GENERIC_FIND_FIRST_BIT
856471b825SIngo Molnar	select GENERIC_IOMAP
866471b825SIngo Molnar	select GENERIC_IRQ_PROBE
876471b825SIngo Molnar	select GENERIC_IRQ_SHOW
886471b825SIngo Molnar	select GENERIC_PENDING_IRQ		if SMP
896471b825SIngo Molnar	select GENERIC_SMP_IDLE_THREAD
906471b825SIngo Molnar	select GENERIC_STRNCPY_FROM_USER
916471b825SIngo Molnar	select GENERIC_STRNLEN_USER
926471b825SIngo Molnar	select GENERIC_TIME_VSYSCALL
936471b825SIngo Molnar	select HAVE_ACPI_APEI			if ACPI
946471b825SIngo Molnar	select HAVE_ACPI_APEI_NMI		if ACPI
956471b825SIngo Molnar	select HAVE_ALIGNED_STRUCT_PAGE		if SLUB
966471b825SIngo Molnar	select HAVE_ARCH_AUDITSYSCALL
975b710f34SKees Cook	select HAVE_ARCH_HARDENED_USERCOPY
986471b825SIngo Molnar	select HAVE_ARCH_HUGE_VMAP		if X86_64 || X86_PAE
996471b825SIngo Molnar	select HAVE_ARCH_JUMP_LABEL
1006471b825SIngo Molnar	select HAVE_ARCH_KASAN			if X86_64 && SPARSEMEM_VMEMMAP
1016471b825SIngo Molnar	select HAVE_ARCH_KGDB
1026471b825SIngo Molnar	select HAVE_ARCH_KMEMCHECK
1039e08f57dSDaniel Cashman	select HAVE_ARCH_MMAP_RND_BITS		if MMU
1049e08f57dSDaniel Cashman	select HAVE_ARCH_MMAP_RND_COMPAT_BITS	if MMU && COMPAT
1056471b825SIngo Molnar	select HAVE_ARCH_SECCOMP_FILTER
1066471b825SIngo Molnar	select HAVE_ARCH_TRACEHOOK
1076471b825SIngo Molnar	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
108e37e43a4SAndy Lutomirski	select HAVE_ARCH_VMAP_STACK		if X86_64
109*c763ea26SIngo Molnar	select HAVE_ARCH_WITHIN_STACK_FRAMES
1106471b825SIngo Molnar	select HAVE_CC_STACKPROTECTOR
1116471b825SIngo Molnar	select HAVE_CMPXCHG_DOUBLE
1126471b825SIngo Molnar	select HAVE_CMPXCHG_LOCAL
1136471b825SIngo Molnar	select HAVE_CONTEXT_TRACKING		if X86_64
114c1bd55f9SJosh Triplett	select HAVE_COPY_THREAD_TLS
1156471b825SIngo Molnar	select HAVE_C_RECORDMCOUNT
1166471b825SIngo Molnar	select HAVE_DEBUG_KMEMLEAK
1176471b825SIngo Molnar	select HAVE_DEBUG_STACKOVERFLOW
1186471b825SIngo Molnar	select HAVE_DMA_API_DEBUG
1199c5a3621SAkinobu Mita	select HAVE_DMA_CONTIGUOUS
120677aa9f7SSteven Rostedt	select HAVE_DYNAMIC_FTRACE
12106aeaaeaSMasami Hiramatsu	select HAVE_DYNAMIC_FTRACE_WITH_REGS
122*c763ea26SIngo Molnar	select HAVE_EBPF_JIT			if X86_64
12358340a07SJohannes Berg	select HAVE_EFFICIENT_UNALIGNED_ACCESS
1245f56a5dfSJiri Slaby	select HAVE_EXIT_THREAD
1256471b825SIngo Molnar	select HAVE_FENTRY			if X86_64
1266471b825SIngo Molnar	select HAVE_FTRACE_MCOUNT_RECORD
1276471b825SIngo Molnar	select HAVE_FUNCTION_GRAPH_TRACER
1286471b825SIngo Molnar	select HAVE_FUNCTION_TRACER
1296b90bd4bSEmese Revfy	select HAVE_GCC_PLUGINS
1300067f129SK.Prasad	select HAVE_HW_BREAKPOINT
1316471b825SIngo Molnar	select HAVE_IDE
1326471b825SIngo Molnar	select HAVE_IOREMAP_PROT
1336471b825SIngo Molnar	select HAVE_IRQ_EXIT_ON_IRQ_STACK	if X86_64
1346471b825SIngo Molnar	select HAVE_IRQ_TIME_ACCOUNTING
1356471b825SIngo Molnar	select HAVE_KERNEL_BZIP2
1366471b825SIngo Molnar	select HAVE_KERNEL_GZIP
1376471b825SIngo Molnar	select HAVE_KERNEL_LZ4
1386471b825SIngo Molnar	select HAVE_KERNEL_LZMA
1396471b825SIngo Molnar	select HAVE_KERNEL_LZO
1406471b825SIngo Molnar	select HAVE_KERNEL_XZ
1416471b825SIngo Molnar	select HAVE_KPROBES
1426471b825SIngo Molnar	select HAVE_KPROBES_ON_FTRACE
1436471b825SIngo Molnar	select HAVE_KRETPROBES
1446471b825SIngo Molnar	select HAVE_KVM
1456471b825SIngo Molnar	select HAVE_LIVEPATCH			if X86_64
1466471b825SIngo Molnar	select HAVE_MEMBLOCK
1476471b825SIngo Molnar	select HAVE_MEMBLOCK_NODE_MAP
1480102752eSFrederic Weisbecker	select HAVE_MIXED_BREAKPOINTS_REGS
14942a0bb3fSPetr Mladek	select HAVE_NMI
1506471b825SIngo Molnar	select HAVE_OPROFILE
1516471b825SIngo Molnar	select HAVE_OPTPROBES
1526471b825SIngo Molnar	select HAVE_PCSPKR_PLATFORM
1536471b825SIngo Molnar	select HAVE_PERF_EVENTS
154c01d4323SFrederic Weisbecker	select HAVE_PERF_EVENTS_NMI
155c5e63197SJiri Olsa	select HAVE_PERF_REGS
156c5ebcedbSJiri Olsa	select HAVE_PERF_USER_STACK_DUMP
1576471b825SIngo Molnar	select HAVE_REGS_AND_STACK_ACCESS_API
158*c763ea26SIngo Molnar	select HAVE_STACK_VALIDATION		if X86_64
1596471b825SIngo Molnar	select HAVE_SYSCALL_TRACEPOINTS
1606471b825SIngo Molnar	select HAVE_UNSTABLE_SCHED_CLOCK
1617c68af6eSAvi Kivity	select HAVE_USER_RETURN_NOTIFIER
162c0185808SThomas Gleixner	select IRQ_FORCED_THREADING
1636471b825SIngo Molnar	select PERF_EVENTS
1643195ef59SPrarit Bhargava	select RTC_LIB
165d6faca40SArnd Bergmann	select RTC_MC146818_LIB
1666471b825SIngo Molnar	select SPARSE_IRQ
16783fe27eaSPranith Kumar	select SRCU
1686471b825SIngo Molnar	select SYSCTL_EXCEPTION_TRACE
16915f4eae7SAndy Lutomirski	select THREAD_INFO_IN_TASK
1706471b825SIngo Molnar	select USER_STACKTRACE_SUPPORT
1716471b825SIngo Molnar	select VIRT_TO_BUS
1726471b825SIngo Molnar	select X86_FEATURE_NAMES		if PROC_FS
1737d8330a5SBalbir Singh
174ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER
1753120e25eSJan Beulich	def_bool y
1763120e25eSJan Beulich	depends on KPROBES || PERF_EVENTS || UPROBES
177ba7e4d13SIngo Molnar
17851b26adaSLinus Torvaldsconfig OUTPUT_FORMAT
17951b26adaSLinus Torvalds	string
18051b26adaSLinus Torvalds	default "elf32-i386" if X86_32
18151b26adaSLinus Torvalds	default "elf64-x86-64" if X86_64
18251b26adaSLinus Torvalds
18373531905SSam Ravnborgconfig ARCH_DEFCONFIG
184b9b39bfbSSam Ravnborg	string
18573531905SSam Ravnborg	default "arch/x86/configs/i386_defconfig" if X86_32
18673531905SSam Ravnborg	default "arch/x86/configs/x86_64_defconfig" if X86_64
187b9b39bfbSSam Ravnborg
1888d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT
1893c2362e6SHarvey Harrison	def_bool y
1908d5fffb9SSam Ravnborg
1918d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT
1923c2362e6SHarvey Harrison	def_bool y
1938d5fffb9SSam Ravnborg
1948d5fffb9SSam Ravnborgconfig MMU
1953c2362e6SHarvey Harrison	def_bool y
1968d5fffb9SSam Ravnborg
1979e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN
1989e08f57dSDaniel Cashman	default 28 if 64BIT
1999e08f57dSDaniel Cashman	default 8
2009e08f57dSDaniel Cashman
2019e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX
2029e08f57dSDaniel Cashman	default 32 if 64BIT
2039e08f57dSDaniel Cashman	default 16
2049e08f57dSDaniel Cashman
2059e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN
2069e08f57dSDaniel Cashman	default 8
2079e08f57dSDaniel Cashman
2089e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX
2099e08f57dSDaniel Cashman	default 16
2109e08f57dSDaniel Cashman
2118d5fffb9SSam Ravnborgconfig SBUS
2128d5fffb9SSam Ravnborg	bool
2138d5fffb9SSam Ravnborg
2143bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE
2153120e25eSJan Beulich	def_bool y
216a6dfa128SKonrad Rzeszutek Wilk	depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
2173bc4e459SFUJITA Tomonori
21818e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH
2194a14d84eSAndrew Morton	def_bool y
22018e98307SFUJITA Tomonori
2218d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA
2223120e25eSJan Beulich	def_bool y
2233120e25eSJan Beulich	depends on ISA_DMA_API
2248d5fffb9SSam Ravnborg
2258d5fffb9SSam Ravnborgconfig GENERIC_BUG
2263c2362e6SHarvey Harrison	def_bool y
2278d5fffb9SSam Ravnborg	depends on BUG
228b93a531eSJan Beulich	select GENERIC_BUG_RELATIVE_POINTERS if X86_64
229b93a531eSJan Beulich
230b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS
231b93a531eSJan Beulich	bool
2328d5fffb9SSam Ravnborg
2338d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT
2343c2362e6SHarvey Harrison	def_bool y
2358d5fffb9SSam Ravnborg
2368d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC
2373120e25eSJan Beulich	def_bool y
2383120e25eSJan Beulich	depends on ISA_DMA_API
2398d5fffb9SSam Ravnborg
2401032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM
2413120e25eSJan Beulich	def_bool y
2421032c0baSSam Ravnborg
2431032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY
2441032c0baSSam Ravnborg	def_bool y
2451032c0baSSam Ravnborg
2469a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX
2479a0b8415Svenkatesh.pallipadi@intel.com	def_bool y
2488d5fffb9SSam Ravnborg
2491b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE
2501b27d05bSPekka Enberg	def_bool y
2511b27d05bSPekka Enberg
252dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA
25389c9c4c5SBrian Gerst	def_bool y
254b32ef636Stravis@sgi.com
25508fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK
25608fc4580STejun Heo	def_bool y
25708fc4580STejun Heo
25808fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK
25911124411STejun Heo	def_bool y
26011124411STejun Heo
261801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE
262801e4062SJohannes Berg	def_bool y
263801e4062SJohannes Berg
264f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE
265f4cb5700SJohannes Berg	def_bool y
266f4cb5700SJohannes Berg
267cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE
268cfe28c5dSSteve Capper	def_bool y
269cfe28c5dSSteve Capper
27053313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB
27153313b2cSSteve Capper	def_bool y
27253313b2cSSteve Capper
2738d5fffb9SSam Ravnborgconfig ZONE_DMA32
274e0fd24a3SJan Beulich	def_bool y if X86_64
2758d5fffb9SSam Ravnborg
2768d5fffb9SSam Ravnborgconfig AUDIT_ARCH
277e0fd24a3SJan Beulich	def_bool y if X86_64
2788d5fffb9SSam Ravnborg
279765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING
280765c68bdSIngo Molnar	def_bool y
281765c68bdSIngo Molnar
2826a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC
2836a11f75bSAkinobu Mita	def_bool y
2846a11f75bSAkinobu Mita
285d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET
286d6f2d75aSAndrey Ryabinin	hex
287d6f2d75aSAndrey Ryabinin	depends on KASAN
288d6f2d75aSAndrey Ryabinin	default 0xdffffc0000000000
289d6f2d75aSAndrey Ryabinin
29069575d38SShane Wangconfig HAVE_INTEL_TXT
29169575d38SShane Wang	def_bool y
2926ea30386SKees Cook	depends on INTEL_IOMMU && ACPI
29369575d38SShane Wang
2946b0c3d44SSam Ravnborgconfig X86_32_SMP
2956b0c3d44SSam Ravnborg	def_bool y
2966b0c3d44SSam Ravnborg	depends on X86_32 && SMP
2976b0c3d44SSam Ravnborg
2986b0c3d44SSam Ravnborgconfig X86_64_SMP
2996b0c3d44SSam Ravnborg	def_bool y
3006b0c3d44SSam Ravnborg	depends on X86_64 && SMP
3016b0c3d44SSam Ravnborg
302ccbeed3aSTejun Heoconfig X86_32_LAZY_GS
303ccbeed3aSTejun Heo	def_bool y
30460a5317fSTejun Heo	depends on X86_32 && !CC_STACKPROTECTOR
305ccbeed3aSTejun Heo
3062b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES
3072b144498SSrikar Dronamraju	def_bool y
3082b144498SSrikar Dronamraju
309d20642f0SRob Herringconfig FIX_EARLYCON_MEM
310d20642f0SRob Herring	def_bool y
311d20642f0SRob Herring
3129ccaf77cSKees Cookconfig DEBUG_RODATA
3139ccaf77cSKees Cook	def_bool y
3149ccaf77cSKees Cook
31598233368SKirill A. Shutemovconfig PGTABLE_LEVELS
31698233368SKirill A. Shutemov	int
31798233368SKirill A. Shutemov	default 4 if X86_64
31898233368SKirill A. Shutemov	default 3 if X86_PAE
31998233368SKirill A. Shutemov	default 2
32098233368SKirill A. Shutemov
321506f1d07SSam Ravnborgsource "init/Kconfig"
322dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer"
3238d5fffb9SSam Ravnborg
324506f1d07SSam Ravnborgmenu "Processor type and features"
325506f1d07SSam Ravnborg
3265ee71535SRandy Dunlapconfig ZONE_DMA
3275ee71535SRandy Dunlap	bool "DMA memory allocation support" if EXPERT
3285ee71535SRandy Dunlap	default y
3295ee71535SRandy Dunlap	help
3305ee71535SRandy Dunlap	  DMA memory allocation support allows devices with less than 32-bit
3315ee71535SRandy Dunlap	  addressing to allocate within the first 16MB of address space.
3325ee71535SRandy Dunlap	  Disable if no such devices will be used.
3335ee71535SRandy Dunlap
3345ee71535SRandy Dunlap	  If unsure, say Y.
3355ee71535SRandy Dunlap
336506f1d07SSam Ravnborgconfig SMP
337506f1d07SSam Ravnborg	bool "Symmetric multi-processing support"
338506f1d07SSam Ravnborg	---help---
339506f1d07SSam Ravnborg	  This enables support for systems with more than one CPU. If you have
3404a474157SRobert Graffham	  a system with only one CPU, say N. If you have a system with more
3414a474157SRobert Graffham	  than one CPU, say Y.
342506f1d07SSam Ravnborg
3434a474157SRobert Graffham	  If you say N here, the kernel will run on uni- and multiprocessor
344506f1d07SSam Ravnborg	  machines, but will use only one CPU of a multiprocessor machine. If
345506f1d07SSam Ravnborg	  you say Y here, the kernel will run on many, but not all,
3464a474157SRobert Graffham	  uniprocessor machines. On a uniprocessor machine, the kernel
347506f1d07SSam Ravnborg	  will run faster if you say N here.
348506f1d07SSam Ravnborg
349506f1d07SSam Ravnborg	  Note that if you say Y here and choose architecture "586" or
350506f1d07SSam Ravnborg	  "Pentium" under "Processor family", the kernel will not work on 486
351506f1d07SSam Ravnborg	  architectures. Similarly, multiprocessor kernels for the "PPro"
352506f1d07SSam Ravnborg	  architecture may not work on all Pentium based boards.
353506f1d07SSam Ravnborg
354506f1d07SSam Ravnborg	  People using multiprocessor machines who say Y here should also say
355506f1d07SSam Ravnborg	  Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
356506f1d07SSam Ravnborg	  Management" code will be disabled if you say Y here.
357506f1d07SSam Ravnborg
358395cf969SPaul Bolle	  See also <file:Documentation/x86/i386/IO-APIC.txt>,
359506f1d07SSam Ravnborg	  <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
360506f1d07SSam Ravnborg	  <http://www.tldp.org/docs.html#howto>.
361506f1d07SSam Ravnborg
362506f1d07SSam Ravnborg	  If you don't know what to do here, say N.
363506f1d07SSam Ravnborg
3649def39beSJosh Triplettconfig X86_FEATURE_NAMES
3659def39beSJosh Triplett	bool "Processor feature human-readable names" if EMBEDDED
3669def39beSJosh Triplett	default y
3679def39beSJosh Triplett	---help---
3689def39beSJosh Triplett	  This option compiles in a table of x86 feature bits and corresponding
3699def39beSJosh Triplett	  names.  This is required to support /proc/cpuinfo and a few kernel
3709def39beSJosh Triplett	  messages.  You can disable this to save space, at the expense of
3719def39beSJosh Triplett	  making those few kernel messages show numeric feature bits instead.
3729def39beSJosh Triplett
3739def39beSJosh Triplett	  If in doubt, say Y.
3749def39beSJosh Triplett
3756e1315feSBorislav Petkovconfig X86_FAST_FEATURE_TESTS
3766e1315feSBorislav Petkov	bool "Fast CPU feature tests" if EMBEDDED
3776e1315feSBorislav Petkov	default y
3786e1315feSBorislav Petkov	---help---
3796e1315feSBorislav Petkov	  Some fast-paths in the kernel depend on the capabilities of the CPU.
3806e1315feSBorislav Petkov	  Say Y here for the kernel to patch in the appropriate code at runtime
3816e1315feSBorislav Petkov	  based on the capabilities of the CPU. The infrastructure for patching
3826e1315feSBorislav Petkov	  code at runtime takes up some additional space; space-constrained
3836e1315feSBorislav Petkov	  embedded systems may wish to say N here to produce smaller, slightly
3846e1315feSBorislav Petkov	  slower code.
3856e1315feSBorislav Petkov
38606cd9a7dSYinghai Luconfig X86_X2APIC
38706cd9a7dSYinghai Lu	bool "Support x2apic"
38819e3d60dSJan Kiszka	depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
38906cd9a7dSYinghai Lu	---help---
39006cd9a7dSYinghai Lu	  This enables x2apic support on CPUs that have this feature.
39106cd9a7dSYinghai Lu
39206cd9a7dSYinghai Lu	  This allows 32-bit apic IDs (so it can support very large systems),
39306cd9a7dSYinghai Lu	  and accesses the local apic via MSRs not via mmio.
39406cd9a7dSYinghai Lu
39506cd9a7dSYinghai Lu	  If you don't know what to do here, say N.
39606cd9a7dSYinghai Lu
3976695c85bSYinghai Luconfig X86_MPPARSE
3986e87f9b7SBin Gao	bool "Enable MPS table" if ACPI || SFI
3997a527688SJan Beulich	default y
4005ab74722SIngo Molnar	depends on X86_LOCAL_APIC
4018f9ca475SIngo Molnar	---help---
4026695c85bSYinghai Lu	  For old smp systems that do not have proper acpi support. Newer systems
4036695c85bSYinghai Lu	  (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
4046695c85bSYinghai Lu
40526f7ef14SYinghai Luconfig X86_BIGSMP
40626f7ef14SYinghai Lu	bool "Support for big SMP systems with more than 8 CPUs"
40726f7ef14SYinghai Lu	depends on X86_32 && SMP
4088f9ca475SIngo Molnar	---help---
40926f7ef14SYinghai Lu	  This option is needed for the systems that have more than 8 CPUs
410506f1d07SSam Ravnborg
411ddd70cf9SJun Nakajimaconfig GOLDFISH
412ddd70cf9SJun Nakajima       def_bool y
413ddd70cf9SJun Nakajima       depends on X86_GOLDFISH
414ddd70cf9SJun Nakajima
4158425091fSRavikiran G Thirumalaiif X86_32
416c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM
417c5c606d9SRavikiran G Thirumalai	bool "Support for extended (non-PC) x86 platforms"
418c5c606d9SRavikiran G Thirumalai	default y
4198f9ca475SIngo Molnar	---help---
42006ac8346SIngo Molnar	  If you disable this option then the kernel will only support
42106ac8346SIngo Molnar	  standard PC platforms. (which covers the vast majority of
42206ac8346SIngo Molnar	  systems out there.)
42306ac8346SIngo Molnar
4248425091fSRavikiran G Thirumalai	  If you enable this option then you'll be able to select support
4258425091fSRavikiran G Thirumalai	  for the following (non-PC) 32 bit x86 platforms:
426cb7b8023SBen Hutchings		Goldfish (Android emulator)
4278425091fSRavikiran G Thirumalai		AMD Elan
4288425091fSRavikiran G Thirumalai		RDC R-321x SoC
4298425091fSRavikiran G Thirumalai		SGI 320/540 (Visual Workstation)
43083125a3aSAlessandro Rubini		STA2X11-based (e.g. Northville)
4313f4110a4SThomas Gleixner		Moorestown MID devices
43206ac8346SIngo Molnar
43306ac8346SIngo Molnar	  If you have one of these systems, or if you want to build a
43406ac8346SIngo Molnar	  generic distribution kernel, say Y here - otherwise say N.
4358425091fSRavikiran G Thirumalaiendif
43606ac8346SIngo Molnar
4378425091fSRavikiran G Thirumalaiif X86_64
4388425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM
4398425091fSRavikiran G Thirumalai	bool "Support for extended (non-PC) x86 platforms"
4408425091fSRavikiran G Thirumalai	default y
4418425091fSRavikiran G Thirumalai	---help---
4428425091fSRavikiran G Thirumalai	  If you disable this option then the kernel will only support
4438425091fSRavikiran G Thirumalai	  standard PC platforms. (which covers the vast majority of
4448425091fSRavikiran G Thirumalai	  systems out there.)
4458425091fSRavikiran G Thirumalai
4468425091fSRavikiran G Thirumalai	  If you enable this option then you'll be able to select support
4478425091fSRavikiran G Thirumalai	  for the following (non-PC) 64 bit x86 platforms:
44844b111b5SSteffen Persvold		Numascale NumaChip
4498425091fSRavikiran G Thirumalai		ScaleMP vSMP
4508425091fSRavikiran G Thirumalai		SGI Ultraviolet
4518425091fSRavikiran G Thirumalai
4528425091fSRavikiran G Thirumalai	  If you have one of these systems, or if you want to build a
4538425091fSRavikiran G Thirumalai	  generic distribution kernel, say Y here - otherwise say N.
4548425091fSRavikiran G Thirumalaiendif
455c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms
456c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions
45744b111b5SSteffen Persvoldconfig X86_NUMACHIP
45844b111b5SSteffen Persvold	bool "Numascale NumaChip"
45944b111b5SSteffen Persvold	depends on X86_64
46044b111b5SSteffen Persvold	depends on X86_EXTENDED_PLATFORM
46144b111b5SSteffen Persvold	depends on NUMA
46244b111b5SSteffen Persvold	depends on SMP
46344b111b5SSteffen Persvold	depends on X86_X2APIC
464f9726bfdSDaniel J Blueman	depends on PCI_MMCONFIG
46544b111b5SSteffen Persvold	---help---
46644b111b5SSteffen Persvold	  Adds support for Numascale NumaChip large-SMP systems. Needed to
46744b111b5SSteffen Persvold	  enable more than ~168 cores.
46844b111b5SSteffen Persvold	  If you don't have one of these, you should say N here.
46903b48632SNick Piggin
4706a48565eSIngo Molnarconfig X86_VSMP
471c5c606d9SRavikiran G Thirumalai	bool "ScaleMP vSMP"
4726276a074SBorislav Petkov	select HYPERVISOR_GUEST
4736a48565eSIngo Molnar	select PARAVIRT
4746a48565eSIngo Molnar	depends on X86_64 && PCI
475c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
476ead91d4bSShai Fultheim	depends on SMP
4778f9ca475SIngo Molnar	---help---
4786a48565eSIngo Molnar	  Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
4796a48565eSIngo Molnar	  supposed to run on these EM64T-based machines.  Only choose this option
4806a48565eSIngo Molnar	  if you have one of these machines.
4816a48565eSIngo Molnar
482c5c606d9SRavikiran G Thirumalaiconfig X86_UV
483c5c606d9SRavikiran G Thirumalai	bool "SGI Ultraviolet"
484c5c606d9SRavikiran G Thirumalai	depends on X86_64
485c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
48654c28d29SJack Steiner	depends on NUMA
4871ecb4ae5SAndrew Morton	depends on EFI
4889d6c26e7SSuresh Siddha	depends on X86_X2APIC
4891222e564SIngo Molnar	depends on PCI
490c5c606d9SRavikiran G Thirumalai	---help---
491c5c606d9SRavikiran G Thirumalai	  This option is needed in order to support SGI Ultraviolet systems.
492c5c606d9SRavikiran G Thirumalai	  If you don't have one of these, you should say N here.
493c5c606d9SRavikiran G Thirumalai
494c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms
495c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions
496506f1d07SSam Ravnborg
497ddd70cf9SJun Nakajimaconfig X86_GOLDFISH
498ddd70cf9SJun Nakajima       bool "Goldfish (Virtual Platform)"
499cb7b8023SBen Hutchings       depends on X86_EXTENDED_PLATFORM
500ddd70cf9SJun Nakajima       ---help---
501ddd70cf9SJun Nakajima	 Enable support for the Goldfish virtual platform used primarily
502ddd70cf9SJun Nakajima	 for Android development. Unless you are building for the Android
503ddd70cf9SJun Nakajima	 Goldfish emulator say N here.
504ddd70cf9SJun Nakajima
505c751e17bSThomas Gleixnerconfig X86_INTEL_CE
506c751e17bSThomas Gleixner	bool "CE4100 TV platform"
507c751e17bSThomas Gleixner	depends on PCI
508c751e17bSThomas Gleixner	depends on PCI_GODIRECT
5096084a6e2SJiang Liu	depends on X86_IO_APIC
510c751e17bSThomas Gleixner	depends on X86_32
511c751e17bSThomas Gleixner	depends on X86_EXTENDED_PLATFORM
51237bc9f50SDirk Brandewie	select X86_REBOOTFIXUPS
513da6b737bSSebastian Andrzej Siewior	select OF
514da6b737bSSebastian Andrzej Siewior	select OF_EARLY_FLATTREE
515c751e17bSThomas Gleixner	---help---
516c751e17bSThomas Gleixner	  Select for the Intel CE media processor (CE4100) SOC.
517c751e17bSThomas Gleixner	  This option compiles in support for the CE4100 SOC for settop
518c751e17bSThomas Gleixner	  boxes and media devices.
519c751e17bSThomas Gleixner
5204cb9b00fSDavid Cohenconfig X86_INTEL_MID
52143605ef1SAlan Cox	bool "Intel MID platform support"
52243605ef1SAlan Cox	depends on X86_EXTENDED_PLATFORM
523edc6bc78SDavid Cohen	depends on X86_PLATFORM_DEVICES
5241ea7c673SAlan Cox	depends on PCI
5253fda5bb4SAndy Shevchenko	depends on X86_64 || (PCI_GOANY && X86_32)
5261ea7c673SAlan Cox	depends on X86_IO_APIC
5277c9c3a1eSAlan Cox	select SFI
5284cb9b00fSDavid Cohen	select I2C
5297c9c3a1eSAlan Cox	select DW_APB_TIMER
5301ea7c673SAlan Cox	select APB_TIMER
5311ea7c673SAlan Cox	select INTEL_SCU_IPC
53215a713dfSMika Westerberg	select MFD_INTEL_MSIC
5331ea7c673SAlan Cox	---help---
5344cb9b00fSDavid Cohen	  Select to build a kernel capable of supporting Intel MID (Mobile
5354cb9b00fSDavid Cohen	  Internet Device) platform systems which do not have the PCI legacy
5364cb9b00fSDavid Cohen	  interfaces. If you are building for a PC class system say N here.
5371ea7c673SAlan Cox
5384cb9b00fSDavid Cohen	  Intel MID platforms are based on an Intel processor and chipset which
5394cb9b00fSDavid Cohen	  consume less power than most of the x86 derivatives.
54043605ef1SAlan Cox
5418bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK
5428bbc2a13SBryan O'Donoghue	bool "Intel Quark platform support"
5438bbc2a13SBryan O'Donoghue	depends on X86_32
5448bbc2a13SBryan O'Donoghue	depends on X86_EXTENDED_PLATFORM
5458bbc2a13SBryan O'Donoghue	depends on X86_PLATFORM_DEVICES
5468bbc2a13SBryan O'Donoghue	depends on X86_TSC
5478bbc2a13SBryan O'Donoghue	depends on PCI
5488bbc2a13SBryan O'Donoghue	depends on PCI_GOANY
5498bbc2a13SBryan O'Donoghue	depends on X86_IO_APIC
5508bbc2a13SBryan O'Donoghue	select IOSF_MBI
5518bbc2a13SBryan O'Donoghue	select INTEL_IMR
5529ab6eb51SAndy Shevchenko	select COMMON_CLK
5538bbc2a13SBryan O'Donoghue	---help---
5548bbc2a13SBryan O'Donoghue	  Select to include support for Quark X1000 SoC.
5558bbc2a13SBryan O'Donoghue	  Say Y here if you have a Quark based system such as the Arduino
5568bbc2a13SBryan O'Donoghue	  compatible Intel Galileo.
5578bbc2a13SBryan O'Donoghue
55858cbbee2SVadim Pasternakconfig MLX_PLATFORM
55958cbbee2SVadim Pasternak	tristate "Mellanox Technologies platform support"
56058cbbee2SVadim Pasternak	depends on X86_64
56158cbbee2SVadim Pasternak	depends on X86_EXTENDED_PLATFORM
56258cbbee2SVadim Pasternak	---help---
56358cbbee2SVadim Pasternak	  This option enables system support for the Mellanox Technologies
56458cbbee2SVadim Pasternak	  platform.
56558cbbee2SVadim Pasternak
56658cbbee2SVadim Pasternak	  Say Y here if you are building a kernel for Mellanox system.
56758cbbee2SVadim Pasternak
56858cbbee2SVadim Pasternak	  Otherwise, say N.
56958cbbee2SVadim Pasternak
5703d48aab1SMika Westerbergconfig X86_INTEL_LPSS
5713d48aab1SMika Westerberg	bool "Intel Low Power Subsystem Support"
572eebb3e8dSAndy Shevchenko	depends on X86 && ACPI
5733d48aab1SMika Westerberg	select COMMON_CLK
5740f531431SMathias Nyman	select PINCTRL
575eebb3e8dSAndy Shevchenko	select IOSF_MBI
5763d48aab1SMika Westerberg	---help---
5773d48aab1SMika Westerberg	  Select to build support for Intel Low Power Subsystem such as
5783d48aab1SMika Westerberg	  found on Intel Lynxpoint PCH. Selecting this option enables
5790f531431SMathias Nyman	  things like clock tree (common clock framework) and pincontrol
5800f531431SMathias Nyman	  which are needed by the LPSS peripheral drivers.
5813d48aab1SMika Westerberg
58292082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE
58392082a88SKen Xue	bool "AMD ACPI2Platform devices support"
58492082a88SKen Xue	depends on ACPI
58592082a88SKen Xue	select COMMON_CLK
58692082a88SKen Xue	select PINCTRL
58792082a88SKen Xue	---help---
58892082a88SKen Xue	  Select to interpret AMD specific ACPI device to platform device
58992082a88SKen Xue	  such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
59092082a88SKen Xue	  I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
59192082a88SKen Xue	  implemented under PINCTRL subsystem.
59292082a88SKen Xue
593ced3ce76SDavid E. Boxconfig IOSF_MBI
594ced3ce76SDavid E. Box	tristate "Intel SoC IOSF Sideband support for SoC platforms"
595ced3ce76SDavid E. Box	depends on PCI
596ced3ce76SDavid E. Box	---help---
597ced3ce76SDavid E. Box	  This option enables sideband register access support for Intel SoC
598ced3ce76SDavid E. Box	  platforms. On these platforms the IOSF sideband is used in lieu of
599ced3ce76SDavid E. Box	  MSR's for some register accesses, mostly but not limited to thermal
600ced3ce76SDavid E. Box	  and power. Drivers may query the availability of this device to
601ced3ce76SDavid E. Box	  determine if they need the sideband in order to work on these
602ced3ce76SDavid E. Box	  platforms. The sideband is available on the following SoC products.
603ced3ce76SDavid E. Box	  This list is not meant to be exclusive.
604ced3ce76SDavid E. Box	   - BayTrail
605ced3ce76SDavid E. Box	   - Braswell
606ced3ce76SDavid E. Box	   - Quark
607ced3ce76SDavid E. Box
608ced3ce76SDavid E. Box	  You should say Y if you are running a kernel on one of these SoC's.
609ced3ce76SDavid E. Box
610ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG
611ed2226bdSDavid E. Box	bool "Enable IOSF sideband access through debugfs"
612ed2226bdSDavid E. Box	depends on IOSF_MBI && DEBUG_FS
613ed2226bdSDavid E. Box	---help---
614ed2226bdSDavid E. Box	  Select this option to expose the IOSF sideband access registers (MCR,
615ed2226bdSDavid E. Box	  MDR, MCRX) through debugfs to write and read register information from
616ed2226bdSDavid E. Box	  different units on the SoC. This is most useful for obtaining device
617ed2226bdSDavid E. Box	  state information for debug and analysis. As this is a general access
618ed2226bdSDavid E. Box	  mechanism, users of this option would have specific knowledge of the
619ed2226bdSDavid E. Box	  device they want to access.
620ed2226bdSDavid E. Box
621ed2226bdSDavid E. Box	  If you don't require the option or are in doubt, say N.
622ed2226bdSDavid E. Box
623c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X
624c5c606d9SRavikiran G Thirumalai	bool "RDC R-321x SoC"
625506f1d07SSam Ravnborg	depends on X86_32
626c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
627c5c606d9SRavikiran G Thirumalai	select M486
628c5c606d9SRavikiran G Thirumalai	select X86_REBOOTFIXUPS
629c5c606d9SRavikiran G Thirumalai	---help---
630c5c606d9SRavikiran G Thirumalai	  This option is needed for RDC R-321x system-on-chip, also known
631c5c606d9SRavikiran G Thirumalai	  as R-8610-(G).
632c5c606d9SRavikiran G Thirumalai	  If you don't have one of these chips, you should say N here.
633c5c606d9SRavikiran G Thirumalai
634e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD
6359c398017SIngo Molnar	bool "Support non-standard 32-bit SMP architectures"
6369c398017SIngo Molnar	depends on X86_32 && SMP
637c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
6388f9ca475SIngo Molnar	---help---
639b5660ba7SH. Peter Anvin	  This option compiles in the bigsmp and STA2X11 default
640b5660ba7SH. Peter Anvin	  subarchitectures.  It is intended for a generic binary
641b5660ba7SH. Peter Anvin	  kernel. If you select them all, kernel will probe it one by
642b5660ba7SH. Peter Anvin	  one and will fallback to default.
643d49c4288SYinghai Lu
644c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms
645d49c4288SYinghai Lu
646d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE
6476fc108a0SJan Beulich	def_bool y
648d949f36fSLinus Torvalds	# MCE code calls memory_failure():
649d949f36fSLinus Torvalds	depends on X86_MCE
650d949f36fSLinus Torvalds	# On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
651d949f36fSLinus Torvalds	# On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
652d949f36fSLinus Torvalds	depends on X86_64 || !SPARSEMEM
653d949f36fSLinus Torvalds	select ARCH_SUPPORTS_MEMORY_FAILURE
654d949f36fSLinus Torvalds
65583125a3aSAlessandro Rubiniconfig STA2X11
65683125a3aSAlessandro Rubini	bool "STA2X11 Companion Chip Support"
65783125a3aSAlessandro Rubini	depends on X86_32_NON_STANDARD && PCI
65883125a3aSAlessandro Rubini	select X86_DEV_DMA_OPS
65983125a3aSAlessandro Rubini	select X86_DMA_REMAP
66083125a3aSAlessandro Rubini	select SWIOTLB
66183125a3aSAlessandro Rubini	select MFD_STA2X11
6620145071bSLinus Walleij	select GPIOLIB
66383125a3aSAlessandro Rubini	default n
66483125a3aSAlessandro Rubini	---help---
66583125a3aSAlessandro Rubini	  This adds support for boards based on the STA2X11 IO-Hub,
66683125a3aSAlessandro Rubini	  a.k.a. "ConneXt". The chip is used in place of the standard
66783125a3aSAlessandro Rubini	  PC chipset, so all "standard" peripherals are missing. If this
66883125a3aSAlessandro Rubini	  option is selected the kernel will still be able to boot on
66983125a3aSAlessandro Rubini	  standard PC machines.
67083125a3aSAlessandro Rubini
67182148d1dSShérabconfig X86_32_IRIS
67282148d1dSShérab	tristate "Eurobraille/Iris poweroff module"
67382148d1dSShérab	depends on X86_32
67482148d1dSShérab	---help---
67582148d1dSShérab	  The Iris machines from EuroBraille do not have APM or ACPI support
67682148d1dSShérab	  to shut themselves down properly.  A special I/O sequence is
67782148d1dSShérab	  needed to do so, which is what this module does at
67882148d1dSShérab	  kernel shutdown.
67982148d1dSShérab
68082148d1dSShérab	  This is only for Iris machines from EuroBraille.
68182148d1dSShérab
68282148d1dSShérab	  If unused, say N.
68382148d1dSShérab
684ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER
6853c2362e6SHarvey Harrison	def_bool y
6863c2362e6SHarvey Harrison	prompt "Single-depth WCHAN output"
687a87d0914SKen Chen	depends on X86
6888f9ca475SIngo Molnar	---help---
689506f1d07SSam Ravnborg	  Calculate simpler /proc/<PID>/wchan values. If this option
690506f1d07SSam Ravnborg	  is disabled then wchan values will recurse back to the
691506f1d07SSam Ravnborg	  caller function. This provides more accurate wchan values,
692506f1d07SSam Ravnborg	  at the expense of slightly more scheduling overhead.
693506f1d07SSam Ravnborg
694506f1d07SSam Ravnborg	  If in doubt, say "Y".
695506f1d07SSam Ravnborg
6966276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST
6976276a074SBorislav Petkov	bool "Linux guest support"
6988f9ca475SIngo Molnar	---help---
6996276a074SBorislav Petkov	  Say Y here to enable options for running Linux under various hyper-
7006276a074SBorislav Petkov	  visors. This option enables basic hypervisor detection and platform
7016276a074SBorislav Petkov	  setup.
702506f1d07SSam Ravnborg
7036276a074SBorislav Petkov	  If you say N, all options in this submenu will be skipped and
7046276a074SBorislav Petkov	  disabled, and Linux guest support won't be built in.
705506f1d07SSam Ravnborg
7066276a074SBorislav Petkovif HYPERVISOR_GUEST
707506f1d07SSam Ravnborg
708e61bd94aSEduardo Pereira Habkostconfig PARAVIRT
709e61bd94aSEduardo Pereira Habkost	bool "Enable paravirtualization code"
7108f9ca475SIngo Molnar	---help---
711e61bd94aSEduardo Pereira Habkost	  This changes the kernel so it can modify itself when it is run
712e61bd94aSEduardo Pereira Habkost	  under a hypervisor, potentially improving performance significantly
713e61bd94aSEduardo Pereira Habkost	  over full virtualization.  However, when run without a hypervisor
714e61bd94aSEduardo Pereira Habkost	  the kernel is theoretically slower and slightly larger.
715e61bd94aSEduardo Pereira Habkost
7166276a074SBorislav Petkovconfig PARAVIRT_DEBUG
7176276a074SBorislav Petkov	bool "paravirt-ops debugging"
7186276a074SBorislav Petkov	depends on PARAVIRT && DEBUG_KERNEL
7196276a074SBorislav Petkov	---help---
7206276a074SBorislav Petkov	  Enable to debug paravirt_ops internals.  Specifically, BUG if
7216276a074SBorislav Petkov	  a paravirt_op is missing when it is called.
7226276a074SBorislav Petkov
723b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS
724b4ecc126SJeremy Fitzhardinge	bool "Paravirtualization layer for spinlocks"
7256ea30386SKees Cook	depends on PARAVIRT && SMP
726b4ecc126SJeremy Fitzhardinge	---help---
727b4ecc126SJeremy Fitzhardinge	  Paravirtualized spinlocks allow a pvops backend to replace the
728b4ecc126SJeremy Fitzhardinge	  spinlock implementation with something virtualization-friendly
729b4ecc126SJeremy Fitzhardinge	  (for example, block the virtual CPU rather than spinning).
730b4ecc126SJeremy Fitzhardinge
7314c4e4f61SRaghavendra K T	  It has a minimal impact on native kernels and gives a nice performance
7324c4e4f61SRaghavendra K T	  benefit on paravirtualized KVM / Xen kernels.
733b4ecc126SJeremy Fitzhardinge
7344c4e4f61SRaghavendra K T	  If you are unsure how to answer this question, answer Y.
735b4ecc126SJeremy Fitzhardinge
73645e898b7SWaiman Longconfig QUEUED_LOCK_STAT
73745e898b7SWaiman Long	bool "Paravirt queued spinlock statistics"
738cfd8983fSPeter Zijlstra	depends on PARAVIRT_SPINLOCKS && DEBUG_FS
73945e898b7SWaiman Long	---help---
74045e898b7SWaiman Long	  Enable the collection of statistical data on the slowpath
74145e898b7SWaiman Long	  behavior of paravirtualized queued spinlocks and report
74245e898b7SWaiman Long	  them on debugfs.
74345e898b7SWaiman Long
7446276a074SBorislav Petkovsource "arch/x86/xen/Kconfig"
7456276a074SBorislav Petkov
7466276a074SBorislav Petkovconfig KVM_GUEST
7476276a074SBorislav Petkov	bool "KVM Guest support (including kvmclock)"
7486276a074SBorislav Petkov	depends on PARAVIRT
7496276a074SBorislav Petkov	select PARAVIRT_CLOCK
7506276a074SBorislav Petkov	default y
7516276a074SBorislav Petkov	---help---
7526276a074SBorislav Petkov	  This option enables various optimizations for running under the KVM
7536276a074SBorislav Petkov	  hypervisor. It includes a paravirtualized clock, so that instead
7546276a074SBorislav Petkov	  of relying on a PIT (or probably other) emulation by the
7556276a074SBorislav Petkov	  underlying device model, the host provides the guest with
7566276a074SBorislav Petkov	  timing infrastructure such as time of day, and system time
7576276a074SBorislav Petkov
7581e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS
7591e20eb85SSrivatsa Vaddagiri	bool "Enable debug information for KVM Guests in debugfs"
7601e20eb85SSrivatsa Vaddagiri	depends on KVM_GUEST && DEBUG_FS
7611e20eb85SSrivatsa Vaddagiri	default n
7621e20eb85SSrivatsa Vaddagiri	---help---
7631e20eb85SSrivatsa Vaddagiri	  This option enables collection of various statistics for KVM guest.
7641e20eb85SSrivatsa Vaddagiri	  Statistics are displayed in debugfs filesystem. Enabling this option
7651e20eb85SSrivatsa Vaddagiri	  may incur significant overhead.
7661e20eb85SSrivatsa Vaddagiri
7676276a074SBorislav Petkovsource "arch/x86/lguest/Kconfig"
7686276a074SBorislav Petkov
7696276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING
7706276a074SBorislav Petkov	bool "Paravirtual steal time accounting"
7716276a074SBorislav Petkov	depends on PARAVIRT
7726276a074SBorislav Petkov	default n
7736276a074SBorislav Petkov	---help---
7746276a074SBorislav Petkov	  Select this option to enable fine granularity task steal time
7756276a074SBorislav Petkov	  accounting. Time spent executing other tasks in parallel with
7766276a074SBorislav Petkov	  the current vCPU is discounted from the vCPU power. To account for
7776276a074SBorislav Petkov	  that, there can be a small performance impact.
7786276a074SBorislav Petkov
7796276a074SBorislav Petkov	  If in doubt, say N here.
7806276a074SBorislav Petkov
7817af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK
7827af192c9SGerd Hoffmann	bool
7837af192c9SGerd Hoffmann
7846276a074SBorislav Petkovendif #HYPERVISOR_GUEST
78597349135SJeremy Fitzhardinge
78608677214SYinghai Luconfig NO_BOOTMEM
787774ea0bcSYinghai Lu	def_bool y
78808677214SYinghai Lu
789506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu"
790506f1d07SSam Ravnborg
791506f1d07SSam Ravnborgconfig HPET_TIMER
7923c2362e6SHarvey Harrison	def_bool X86_64
793506f1d07SSam Ravnborg	prompt "HPET Timer Support" if X86_32
7948f9ca475SIngo Molnar	---help---
795506f1d07SSam Ravnborg	  Use the IA-PC HPET (High Precision Event Timer) to manage
796506f1d07SSam Ravnborg	  time in preference to the PIT and RTC, if a HPET is
797506f1d07SSam Ravnborg	  present.
798506f1d07SSam Ravnborg	  HPET is the next generation timer replacing legacy 8254s.
799506f1d07SSam Ravnborg	  The HPET provides a stable time base on SMP
800506f1d07SSam Ravnborg	  systems, unlike the TSC, but it is more expensive to access,
8014e7f9df2SMichael S. Tsirkin	  as it is off-chip.  The interface used is documented
8024e7f9df2SMichael S. Tsirkin	  in the HPET spec, revision 1.
803506f1d07SSam Ravnborg
804506f1d07SSam Ravnborg	  You can safely choose Y here.  However, HPET will only be
805506f1d07SSam Ravnborg	  activated if the platform and the BIOS support this feature.
806506f1d07SSam Ravnborg	  Otherwise the 8254 will be used for timing services.
807506f1d07SSam Ravnborg
808506f1d07SSam Ravnborg	  Choose N to continue using the legacy 8254 timer.
809506f1d07SSam Ravnborg
810506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC
8113c2362e6SHarvey Harrison	def_bool y
8129d8af78bSBernhard Walle	depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
813506f1d07SSam Ravnborg
814bb24c471SJacob Panconfig APB_TIMER
815933b9463SAlan Cox       def_bool y if X86_INTEL_MID
816933b9463SAlan Cox       prompt "Intel MID APB Timer Support" if X86_INTEL_MID
81706c3df49SJamie Iles       select DW_APB_TIMER
818a0c3832aSAlan Cox       depends on X86_INTEL_MID && SFI
819bb24c471SJacob Pan       help
820bb24c471SJacob Pan         APB timer is the replacement for 8254, HPET on X86 MID platforms.
821bb24c471SJacob Pan         The APBT provides a stable time base on SMP
822bb24c471SJacob Pan         systems, unlike the TSC, but it is more expensive to access,
823bb24c471SJacob Pan         as it is off-chip. APB timers are always running regardless of CPU
824bb24c471SJacob Pan         C states, they are used as per CPU clockevent device when possible.
825bb24c471SJacob Pan
8266a108a14SDavid Rientjes# Mark as expert because too many people got it wrong.
827506f1d07SSam Ravnborg# The code disables itself when not needed.
8287ae9392cSThomas Petazzoniconfig DMI
8297ae9392cSThomas Petazzoni	default y
830cf074402SArd Biesheuvel	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
8316a108a14SDavid Rientjes	bool "Enable DMI scanning" if EXPERT
8328f9ca475SIngo Molnar	---help---
8337ae9392cSThomas Petazzoni	  Enabled scanning of DMI to identify machine quirks. Say Y
8347ae9392cSThomas Petazzoni	  here unless you have verified that your setup is not
8357ae9392cSThomas Petazzoni	  affected by entries in the DMI blacklist. Required by PNP
8367ae9392cSThomas Petazzoni	  BIOS code.
8377ae9392cSThomas Petazzoni
838506f1d07SSam Ravnborgconfig GART_IOMMU
83938901f1cSAndi Kleen	bool "Old AMD GART IOMMU support"
840506f1d07SSam Ravnborg	select SWIOTLB
84123ac4ae8SAndreas Herrmann	depends on X86_64 && PCI && AMD_NB
8428f9ca475SIngo Molnar	---help---
843ced3c42cSIngo Molnar	  Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
844ced3c42cSIngo Molnar	  GART based hardware IOMMUs.
845ced3c42cSIngo Molnar
846ced3c42cSIngo Molnar	  The GART supports full DMA access for devices with 32-bit access
847ced3c42cSIngo Molnar	  limitations, on systems with more than 3 GB. This is usually needed
848ced3c42cSIngo Molnar	  for USB, sound, many IDE/SATA chipsets and some other devices.
849ced3c42cSIngo Molnar
850ced3c42cSIngo Molnar	  Newer systems typically have a modern AMD IOMMU, supported via
851ced3c42cSIngo Molnar	  the CONFIG_AMD_IOMMU=y config option.
852ced3c42cSIngo Molnar
853ced3c42cSIngo Molnar	  In normal configurations this driver is only active when needed:
854ced3c42cSIngo Molnar	  there's more than 3 GB of memory and the system contains a
855ced3c42cSIngo Molnar	  32-bit limited device.
856ced3c42cSIngo Molnar
857ced3c42cSIngo Molnar	  If unsure, say Y.
858506f1d07SSam Ravnborg
859506f1d07SSam Ravnborgconfig CALGARY_IOMMU
860506f1d07SSam Ravnborg	bool "IBM Calgary IOMMU support"
861506f1d07SSam Ravnborg	select SWIOTLB
8626ea30386SKees Cook	depends on X86_64 && PCI
8638f9ca475SIngo Molnar	---help---
864506f1d07SSam Ravnborg	  Support for hardware IOMMUs in IBM's xSeries x366 and x460
865506f1d07SSam Ravnborg	  systems. Needed to run systems with more than 3GB of memory
866506f1d07SSam Ravnborg	  properly with 32-bit PCI devices that do not support DAC
867506f1d07SSam Ravnborg	  (Double Address Cycle). Calgary also supports bus level
868506f1d07SSam Ravnborg	  isolation, where all DMAs pass through the IOMMU.  This
869506f1d07SSam Ravnborg	  prevents them from going anywhere except their intended
870506f1d07SSam Ravnborg	  destination. This catches hard-to-find kernel bugs and
871506f1d07SSam Ravnborg	  mis-behaving drivers and devices that do not use the DMA-API
872506f1d07SSam Ravnborg	  properly to set up their DMA buffers.  The IOMMU can be
873506f1d07SSam Ravnborg	  turned off at boot time with the iommu=off parameter.
874506f1d07SSam Ravnborg	  Normally the kernel will make the right choice by itself.
875506f1d07SSam Ravnborg	  If unsure, say Y.
876506f1d07SSam Ravnborg
877506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT
8783c2362e6SHarvey Harrison	def_bool y
8793c2362e6SHarvey Harrison	prompt "Should Calgary be enabled by default?"
880506f1d07SSam Ravnborg	depends on CALGARY_IOMMU
8818f9ca475SIngo Molnar	---help---
882506f1d07SSam Ravnborg	  Should Calgary be enabled by default? if you choose 'y', Calgary
883506f1d07SSam Ravnborg	  will be used (if it exists). If you choose 'n', Calgary will not be
884506f1d07SSam Ravnborg	  used even if it exists. If you choose 'n' and would like to use
885506f1d07SSam Ravnborg	  Calgary anyway, pass 'iommu=calgary' on the kernel command line.
886506f1d07SSam Ravnborg	  If unsure, say Y.
887506f1d07SSam Ravnborg
888506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround
889506f1d07SSam Ravnborgconfig SWIOTLB
890a1afd01cSJoerg Roedel	def_bool y if X86_64
8918f9ca475SIngo Molnar	---help---
892506f1d07SSam Ravnborg	  Support for software bounce buffers used on x86-64 systems
8934454d327SJoe Millenbach	  which don't have a hardware IOMMU. Using this PCI devices
8944454d327SJoe Millenbach	  which can only access 32-bits of memory can be used on systems
8954454d327SJoe Millenbach	  with more than 3 GB of memory.
8964454d327SJoe Millenbach	  If unsure, say Y.
897506f1d07SSam Ravnborg
898a8522509SFUJITA Tomonoriconfig IOMMU_HELPER
8993120e25eSJan Beulich	def_bool y
9003120e25eSJan Beulich	depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
901d25e26b6SLinus Torvalds
9021184dc2fSMike Travisconfig MAXSMP
903ddb0c5a6SSamuel Thibault	bool "Enable Maximum number of SMP Processors and NUMA Nodes"
9046ea30386SKees Cook	depends on X86_64 && SMP && DEBUG_KERNEL
90536f5101aSMike Travis	select CPUMASK_OFFSTACK
9068f9ca475SIngo Molnar	---help---
907ddb0c5a6SSamuel Thibault	  Enable maximum number of CPUS and NUMA Nodes for this architecture.
9081184dc2fSMike Travis	  If unsure, say N.
909506f1d07SSam Ravnborg
910506f1d07SSam Ravnborgconfig NR_CPUS
91136f5101aSMike Travis	int "Maximum number of CPUs" if SMP && !MAXSMP
9122a3313f4SMichael K. Johnson	range 2 8 if SMP && X86_32 && !X86_BIGSMP
913bb61ccc7SJosh Boyer	range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
914b53b5edaSJosh Boyer	range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
91578637a97SMike Travis	default "1" if !SMP
916b53b5edaSJosh Boyer	default "8192" if MAXSMP
917b5660ba7SH. Peter Anvin	default "32" if SMP && X86_BIGSMP
918c5c19941SKirill A. Shutemov	default "8" if SMP && X86_32
919c5c19941SKirill A. Shutemov	default "64" if SMP
9208f9ca475SIngo Molnar	---help---
921506f1d07SSam Ravnborg	  This allows you to specify the maximum number of CPUs which this
922bb61ccc7SJosh Boyer	  kernel will support.  If CPUMASK_OFFSTACK is enabled, the maximum
923cad14bb9SKirill A. Shutemov	  supported value is 8192, otherwise the maximum value is 512.  The
924506f1d07SSam Ravnborg	  minimum value which makes sense is 2.
925506f1d07SSam Ravnborg
926506f1d07SSam Ravnborg	  This is purely to save memory - each supported CPU adds
927506f1d07SSam Ravnborg	  approximately eight kilobytes to the kernel image.
928506f1d07SSam Ravnborg
929506f1d07SSam Ravnborgconfig SCHED_SMT
930506f1d07SSam Ravnborg	bool "SMT (Hyperthreading) scheduler support"
931c8e56d20SBorislav Petkov	depends on SMP
9328f9ca475SIngo Molnar	---help---
933506f1d07SSam Ravnborg	  SMT scheduler support improves the CPU scheduler's decision making
934506f1d07SSam Ravnborg	  when dealing with Intel Pentium 4 chips with HyperThreading at a
935506f1d07SSam Ravnborg	  cost of slightly increased overhead in some places. If unsure say
936506f1d07SSam Ravnborg	  N here.
937506f1d07SSam Ravnborg
938506f1d07SSam Ravnborgconfig SCHED_MC
9393c2362e6SHarvey Harrison	def_bool y
9403c2362e6SHarvey Harrison	prompt "Multi-core scheduler support"
941c8e56d20SBorislav Petkov	depends on SMP
9428f9ca475SIngo Molnar	---help---
943506f1d07SSam Ravnborg	  Multi-core scheduler support improves the CPU scheduler's decision
944506f1d07SSam Ravnborg	  making when dealing with multi-core CPU chips at a cost of slightly
945506f1d07SSam Ravnborg	  increased overhead in some places. If unsure say N here.
946506f1d07SSam Ravnborg
947506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt"
948506f1d07SSam Ravnborg
94930b8b006SThomas Gleixnerconfig UP_LATE_INIT
95030b8b006SThomas Gleixner       def_bool y
951ba360f88SThomas Gleixner       depends on !SMP && X86_LOCAL_APIC
95230b8b006SThomas Gleixner
953506f1d07SSam Ravnborgconfig X86_UP_APIC
95450849eefSJan Beulich	bool "Local APIC support on uniprocessors" if !PCI_MSI
95550849eefSJan Beulich	default PCI_MSI
95638a1dfdaSBryan O'Donoghue	depends on X86_32 && !SMP && !X86_32_NON_STANDARD
9578f9ca475SIngo Molnar	---help---
958506f1d07SSam Ravnborg	  A local APIC (Advanced Programmable Interrupt Controller) is an
959506f1d07SSam Ravnborg	  integrated interrupt controller in the CPU. If you have a single-CPU
960506f1d07SSam Ravnborg	  system which has a processor with a local APIC, you can say Y here to
961506f1d07SSam Ravnborg	  enable and use it. If you say Y here even though your machine doesn't
962506f1d07SSam Ravnborg	  have a local APIC, then the kernel will still run with no slowdown at
963506f1d07SSam Ravnborg	  all. The local APIC supports CPU-generated self-interrupts (timer,
964506f1d07SSam Ravnborg	  performance counters), and the NMI watchdog which detects hard
965506f1d07SSam Ravnborg	  lockups.
966506f1d07SSam Ravnborg
967506f1d07SSam Ravnborgconfig X86_UP_IOAPIC
968506f1d07SSam Ravnborg	bool "IO-APIC support on uniprocessors"
969506f1d07SSam Ravnborg	depends on X86_UP_APIC
9708f9ca475SIngo Molnar	---help---
971506f1d07SSam Ravnborg	  An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
972506f1d07SSam Ravnborg	  SMP-capable replacement for PC-style interrupt controllers. Most
973506f1d07SSam Ravnborg	  SMP systems and many recent uniprocessor systems have one.
974506f1d07SSam Ravnborg
975506f1d07SSam Ravnborg	  If you have a single-CPU system with an IO-APIC, you can say Y here
976506f1d07SSam Ravnborg	  to use it. If you say Y here even though your machine doesn't have
977506f1d07SSam Ravnborg	  an IO-APIC, then the kernel will still run with no slowdown at all.
978506f1d07SSam Ravnborg
979506f1d07SSam Ravnborgconfig X86_LOCAL_APIC
9803c2362e6SHarvey Harrison	def_bool y
9810dbc6078SThomas Petazzoni	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
982b5dc8e6cSJiang Liu	select IRQ_DOMAIN_HIERARCHY
98352f518a3SJiang Liu	select PCI_MSI_IRQ_DOMAIN if PCI_MSI
984506f1d07SSam Ravnborg
985506f1d07SSam Ravnborgconfig X86_IO_APIC
986b1da1e71SJan Beulich	def_bool y
987b1da1e71SJan Beulich	depends on X86_LOCAL_APIC || X86_UP_IOAPIC
988506f1d07SSam Ravnborg
98941b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS
99041b9eb26SStefan Assmann	bool "Reroute for broken boot IRQs"
99141b9eb26SStefan Assmann	depends on X86_IO_APIC
9928f9ca475SIngo Molnar	---help---
99341b9eb26SStefan Assmann	  This option enables a workaround that fixes a source of
99441b9eb26SStefan Assmann	  spurious interrupts. This is recommended when threaded
99541b9eb26SStefan Assmann	  interrupt handling is used on systems where the generation of
99641b9eb26SStefan Assmann	  superfluous "boot interrupts" cannot be disabled.
99741b9eb26SStefan Assmann
99841b9eb26SStefan Assmann	  Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
99941b9eb26SStefan Assmann	  entry in the chipset's IO-APIC is masked (as, e.g. the RT
100041b9eb26SStefan Assmann	  kernel does during interrupt handling). On chipsets where this
100141b9eb26SStefan Assmann	  boot IRQ generation cannot be disabled, this workaround keeps
100241b9eb26SStefan Assmann	  the original IRQ line masked so that only the equivalent "boot
100341b9eb26SStefan Assmann	  IRQ" is delivered to the CPUs. The workaround also tells the
100441b9eb26SStefan Assmann	  kernel to set up the IRQ handler on the boot IRQ line. In this
100541b9eb26SStefan Assmann	  way only one interrupt is delivered to the kernel. Otherwise
100641b9eb26SStefan Assmann	  the spurious second interrupt may cause the kernel to bring
100741b9eb26SStefan Assmann	  down (vital) interrupt lines.
100841b9eb26SStefan Assmann
100941b9eb26SStefan Assmann	  Only affects "broken" chipsets. Interrupt sharing may be
101041b9eb26SStefan Assmann	  increased on these systems.
101141b9eb26SStefan Assmann
1012506f1d07SSam Ravnborgconfig X86_MCE
1013bab9bc65SAndi Kleen	bool "Machine Check / overheating reporting"
1014648ed940SChen, Gong	select GENERIC_ALLOCATOR
1015e57dbaf7SBorislav Petkov	default y
1016506f1d07SSam Ravnborg	---help---
1017bab9bc65SAndi Kleen	  Machine Check support allows the processor to notify the
1018bab9bc65SAndi Kleen	  kernel if it detects a problem (e.g. overheating, data corruption).
1019506f1d07SSam Ravnborg	  The action the kernel takes depends on the severity of the problem,
1020bab9bc65SAndi Kleen	  ranging from warning messages to halting the machine.
10214efc0670SAndi Kleen
1022506f1d07SSam Ravnborgconfig X86_MCE_INTEL
10233c2362e6SHarvey Harrison	def_bool y
10243c2362e6SHarvey Harrison	prompt "Intel MCE features"
1025c1ebf835SAndi Kleen	depends on X86_MCE && X86_LOCAL_APIC
10268f9ca475SIngo Molnar	---help---
1027506f1d07SSam Ravnborg	   Additional support for intel specific MCE features such as
1028506f1d07SSam Ravnborg	   the thermal monitor.
1029506f1d07SSam Ravnborg
1030506f1d07SSam Ravnborgconfig X86_MCE_AMD
10313c2362e6SHarvey Harrison	def_bool y
10323c2362e6SHarvey Harrison	prompt "AMD MCE features"
1033c1ebf835SAndi Kleen	depends on X86_MCE && X86_LOCAL_APIC
10348f9ca475SIngo Molnar	---help---
1035506f1d07SSam Ravnborg	   Additional support for AMD specific MCE features such as
1036506f1d07SSam Ravnborg	   the DRAM Error Threshold.
1037506f1d07SSam Ravnborg
10384efc0670SAndi Kleenconfig X86_ANCIENT_MCE
10396fc108a0SJan Beulich	bool "Support for old Pentium 5 / WinChip machine checks"
1040c31d9633SAndi Kleen	depends on X86_32 && X86_MCE
10414efc0670SAndi Kleen	---help---
10424efc0670SAndi Kleen	  Include support for machine check handling on old Pentium 5 or WinChip
10435065a706SMasanari Iida	  systems. These typically need to be enabled explicitly on the command
10444efc0670SAndi Kleen	  line.
10454efc0670SAndi Kleen
1046b2762686SAndi Kleenconfig X86_MCE_THRESHOLD
1047b2762686SAndi Kleen	depends on X86_MCE_AMD || X86_MCE_INTEL
10486fc108a0SJan Beulich	def_bool y
1049b2762686SAndi Kleen
1050ea149b36SAndi Kleenconfig X86_MCE_INJECT
1051c1ebf835SAndi Kleen	depends on X86_MCE
1052ea149b36SAndi Kleen	tristate "Machine check injector support"
1053ea149b36SAndi Kleen	---help---
1054ea149b36SAndi Kleen	  Provide support for injecting machine checks for testing purposes.
1055ea149b36SAndi Kleen	  If you don't know what a machine check is and you don't do kernel
1056ea149b36SAndi Kleen	  QA it is safe to say n.
1057ea149b36SAndi Kleen
10584efc0670SAndi Kleenconfig X86_THERMAL_VECTOR
10594efc0670SAndi Kleen	def_bool y
10605bb38adcSAndi Kleen	depends on X86_MCE_INTEL
10614efc0670SAndi Kleen
106207dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig"
1063e633c65aSKan Liang
10645aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86
10651e642812SIngo Molnar	bool "Legacy VM86 support"
10665aef51c3SAndy Lutomirski	default n
1067506f1d07SSam Ravnborg	depends on X86_32
10688f9ca475SIngo Molnar	---help---
10695aef51c3SAndy Lutomirski	  This option allows user programs to put the CPU into V8086
10705aef51c3SAndy Lutomirski	  mode, which is an 80286-era approximation of 16-bit real mode.
10715aef51c3SAndy Lutomirski
10725aef51c3SAndy Lutomirski	  Some very old versions of X and/or vbetool require this option
10735aef51c3SAndy Lutomirski	  for user mode setting.  Similarly, DOSEMU will use it if
10745aef51c3SAndy Lutomirski	  available to accelerate real mode DOS programs.  However, any
10755aef51c3SAndy Lutomirski	  recent version of DOSEMU, X, or vbetool should be fully
10765aef51c3SAndy Lutomirski	  functional even without kernel VM86 support, as they will all
10771e642812SIngo Molnar	  fall back to software emulation. Nevertheless, if you are using
10781e642812SIngo Molnar	  a 16-bit DOS program where 16-bit performance matters, vm86
10791e642812SIngo Molnar	  mode might be faster than emulation and you might want to
10801e642812SIngo Molnar	  enable this option.
10815aef51c3SAndy Lutomirski
10821e642812SIngo Molnar	  Note that any app that works on a 64-bit kernel is unlikely to
10831e642812SIngo Molnar	  need this option, as 64-bit kernels don't, and can't, support
10841e642812SIngo Molnar	  V8086 mode. This option is also unrelated to 16-bit protected
10851e642812SIngo Molnar	  mode and is not needed to run most 16-bit programs under Wine.
10865aef51c3SAndy Lutomirski
10871e642812SIngo Molnar	  Enabling this option increases the complexity of the kernel
10881e642812SIngo Molnar	  and slows down exception handling a tiny bit.
10895aef51c3SAndy Lutomirski
10901e642812SIngo Molnar	  If unsure, say N here.
10915aef51c3SAndy Lutomirski
10925aef51c3SAndy Lutomirskiconfig VM86
10935aef51c3SAndy Lutomirski       bool
10945aef51c3SAndy Lutomirski       default X86_LEGACY_VM86
109534273f41SH. Peter Anvin
109634273f41SH. Peter Anvinconfig X86_16BIT
109734273f41SH. Peter Anvin	bool "Enable support for 16-bit segments" if EXPERT
109834273f41SH. Peter Anvin	default y
1099a5b9e5a2SAndy Lutomirski	depends on MODIFY_LDT_SYSCALL
110034273f41SH. Peter Anvin	---help---
110134273f41SH. Peter Anvin	  This option is required by programs like Wine to run 16-bit
110234273f41SH. Peter Anvin	  protected mode legacy code on x86 processors.  Disabling
110334273f41SH. Peter Anvin	  this option saves about 300 bytes on i386, or around 6K text
110434273f41SH. Peter Anvin	  plus 16K runtime memory on x86-64,
110534273f41SH. Peter Anvin
110634273f41SH. Peter Anvinconfig X86_ESPFIX32
110734273f41SH. Peter Anvin	def_bool y
110834273f41SH. Peter Anvin	depends on X86_16BIT && X86_32
1109506f1d07SSam Ravnborg
1110197725deSH. Peter Anvinconfig X86_ESPFIX64
1111197725deSH. Peter Anvin	def_bool y
111234273f41SH. Peter Anvin	depends on X86_16BIT && X86_64
1113506f1d07SSam Ravnborg
11141ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION
11151ad83c85SAndy Lutomirski       bool "Enable vsyscall emulation" if EXPERT
11161ad83c85SAndy Lutomirski       default y
11171ad83c85SAndy Lutomirski       depends on X86_64
11181ad83c85SAndy Lutomirski       ---help---
11191ad83c85SAndy Lutomirski	 This enables emulation of the legacy vsyscall page.  Disabling
11201ad83c85SAndy Lutomirski	 it is roughly equivalent to booting with vsyscall=none, except
11211ad83c85SAndy Lutomirski	 that it will also disable the helpful warning if a program
11221ad83c85SAndy Lutomirski	 tries to use a vsyscall.  With this option set to N, offending
11231ad83c85SAndy Lutomirski	 programs will just segfault, citing addresses of the form
11241ad83c85SAndy Lutomirski	 0xffffffffff600?00.
11251ad83c85SAndy Lutomirski
11261ad83c85SAndy Lutomirski	 This option is required by many programs built before 2013, and
11271ad83c85SAndy Lutomirski	 care should be used even with newer programs if set to N.
11281ad83c85SAndy Lutomirski
11291ad83c85SAndy Lutomirski	 Disabling this option saves about 7K of kernel size and
11301ad83c85SAndy Lutomirski	 possibly 4K of additional runtime pagetable memory.
11311ad83c85SAndy Lutomirski
1132506f1d07SSam Ravnborgconfig TOSHIBA
1133506f1d07SSam Ravnborg	tristate "Toshiba Laptop support"
1134506f1d07SSam Ravnborg	depends on X86_32
1135506f1d07SSam Ravnborg	---help---
1136506f1d07SSam Ravnborg	  This adds a driver to safely access the System Management Mode of
1137506f1d07SSam Ravnborg	  the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1138506f1d07SSam Ravnborg	  not work on models with a Phoenix BIOS. The System Management Mode
1139506f1d07SSam Ravnborg	  is used to set the BIOS and power saving options on Toshiba portables.
1140506f1d07SSam Ravnborg
1141506f1d07SSam Ravnborg	  For information on utilities to make use of this driver see the
1142506f1d07SSam Ravnborg	  Toshiba Linux utilities web site at:
1143506f1d07SSam Ravnborg	  <http://www.buzzard.org.uk/toshiba/>.
1144506f1d07SSam Ravnborg
1145506f1d07SSam Ravnborg	  Say Y if you intend to run this kernel on a Toshiba portable.
1146506f1d07SSam Ravnborg	  Say N otherwise.
1147506f1d07SSam Ravnborg
1148506f1d07SSam Ravnborgconfig I8K
1149039ae585SPali Rohár	tristate "Dell i8k legacy laptop support"
1150949a9d70SJean Delvare	select HWMON
1151039ae585SPali Rohár	select SENSORS_DELL_SMM
1152506f1d07SSam Ravnborg	---help---
1153039ae585SPali Rohár	  This option enables legacy /proc/i8k userspace interface in hwmon
1154039ae585SPali Rohár	  dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1155039ae585SPali Rohár	  temperature and allows controlling fan speeds of Dell laptops via
1156039ae585SPali Rohár	  System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1157039ae585SPali Rohár	  it reports also power and hotkey status. For fan speed control is
1158039ae585SPali Rohár	  needed userspace package i8kutils.
1159506f1d07SSam Ravnborg
1160039ae585SPali Rohár	  Say Y if you intend to run this kernel on old Dell laptops or want to
1161039ae585SPali Rohár	  use userspace package i8kutils.
1162506f1d07SSam Ravnborg	  Say N otherwise.
1163506f1d07SSam Ravnborg
1164506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS
11659ba16087SJan Beulich	bool "Enable X86 board specific fixups for reboot"
11669ba16087SJan Beulich	depends on X86_32
1167506f1d07SSam Ravnborg	---help---
1168506f1d07SSam Ravnborg	  This enables chipset and/or board specific fixups to be done
1169506f1d07SSam Ravnborg	  in order to get reboot to work correctly. This is only needed on
1170506f1d07SSam Ravnborg	  some combinations of hardware and BIOS. The symptom, for which
1171506f1d07SSam Ravnborg	  this config is intended, is when reboot ends with a stalled/hung
1172506f1d07SSam Ravnborg	  system.
1173506f1d07SSam Ravnborg
1174506f1d07SSam Ravnborg	  Currently, the only fixup is for the Geode machines using
11755e3a77e9SFlorian Fainelli	  CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1176506f1d07SSam Ravnborg
1177506f1d07SSam Ravnborg	  Say Y if you want to enable the fixup. Currently, it's safe to
1178506f1d07SSam Ravnborg	  enable this option even if you don't need it.
1179506f1d07SSam Ravnborg	  Say N otherwise.
1180506f1d07SSam Ravnborg
1181506f1d07SSam Ravnborgconfig MICROCODE
11829a2bc335SBorislav Petkov	bool "CPU microcode loading support"
11839a2bc335SBorislav Petkov	default y
118480030e3dSBorislav Petkov	depends on CPU_SUP_AMD || CPU_SUP_INTEL
1185506f1d07SSam Ravnborg	select FW_LOADER
1186506f1d07SSam Ravnborg	---help---
1187506f1d07SSam Ravnborg	  If you say Y here, you will be able to update the microcode on
11885f9c01aaSBorislav Petkov	  Intel and AMD processors. The Intel support is for the IA32 family,
11895f9c01aaSBorislav Petkov	  e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
11905f9c01aaSBorislav Petkov	  AMD support is for families 0x10 and later. You will obviously need
11915f9c01aaSBorislav Petkov	  the actual microcode binary data itself which is not shipped with
11925f9c01aaSBorislav Petkov	  the Linux kernel.
1193506f1d07SSam Ravnborg
11945f9c01aaSBorislav Petkov	  The preferred method to load microcode from a detached initrd is described
11955f9c01aaSBorislav Petkov	  in Documentation/x86/early-microcode.txt. For that you need to enable
11965f9c01aaSBorislav Petkov	  CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
11975f9c01aaSBorislav Petkov	  initrd for microcode blobs.
1198506f1d07SSam Ravnborg
11995f9c01aaSBorislav Petkov	  In addition, you can build-in the microcode into the kernel. For that you
12005f9c01aaSBorislav Petkov	  need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode
12015f9c01aaSBorislav Petkov	  to the CONFIG_EXTRA_FIRMWARE config option.
1202506f1d07SSam Ravnborg
12038d86f390SPeter Orubaconfig MICROCODE_INTEL
1204e43f6e67SBorislav Petkov	bool "Intel microcode loading support"
12058d86f390SPeter Oruba	depends on MICROCODE
12068d86f390SPeter Oruba	default MICROCODE
12078d86f390SPeter Oruba	select FW_LOADER
12088f9ca475SIngo Molnar	---help---
12098d86f390SPeter Oruba	  This options enables microcode patch loading support for Intel
12108d86f390SPeter Oruba	  processors.
12118d86f390SPeter Oruba
1212b8989db9SAlan	  For the current Intel microcode data package go to
1213b8989db9SAlan	  <https://downloadcenter.intel.com> and search for
1214b8989db9SAlan	  'Linux Processor Microcode Data File'.
12158d86f390SPeter Oruba
121680cc9f10SPeter Orubaconfig MICROCODE_AMD
1217e43f6e67SBorislav Petkov	bool "AMD microcode loading support"
121880cc9f10SPeter Oruba	depends on MICROCODE
121980cc9f10SPeter Oruba	select FW_LOADER
12208f9ca475SIngo Molnar	---help---
122180cc9f10SPeter Oruba	  If you select this option, microcode patch loading support for AMD
122280cc9f10SPeter Oruba	  processors will be enabled.
122380cc9f10SPeter Oruba
1224506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE
12253c2362e6SHarvey Harrison	def_bool y
1226506f1d07SSam Ravnborg	depends on MICROCODE
1227506f1d07SSam Ravnborg
1228506f1d07SSam Ravnborgconfig X86_MSR
1229506f1d07SSam Ravnborg	tristate "/dev/cpu/*/msr - Model-specific register support"
12308f9ca475SIngo Molnar	---help---
1231506f1d07SSam Ravnborg	  This device gives privileged processes access to the x86
1232506f1d07SSam Ravnborg	  Model-Specific Registers (MSRs).  It is a character device with
1233506f1d07SSam Ravnborg	  major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1234506f1d07SSam Ravnborg	  MSR accesses are directed to a specific CPU on multi-processor
1235506f1d07SSam Ravnborg	  systems.
1236506f1d07SSam Ravnborg
1237506f1d07SSam Ravnborgconfig X86_CPUID
1238506f1d07SSam Ravnborg	tristate "/dev/cpu/*/cpuid - CPU information support"
12398f9ca475SIngo Molnar	---help---
1240506f1d07SSam Ravnborg	  This device gives processes access to the x86 CPUID instruction to
1241506f1d07SSam Ravnborg	  be executed on a specific processor.  It is a character device
1242506f1d07SSam Ravnborg	  with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1243506f1d07SSam Ravnborg	  /dev/cpu/31/cpuid.
1244506f1d07SSam Ravnborg
1245506f1d07SSam Ravnborgchoice
1246506f1d07SSam Ravnborg	prompt "High Memory Support"
12476fc108a0SJan Beulich	default HIGHMEM4G
1248506f1d07SSam Ravnborg	depends on X86_32
1249506f1d07SSam Ravnborg
1250506f1d07SSam Ravnborgconfig NOHIGHMEM
1251506f1d07SSam Ravnborg	bool "off"
1252506f1d07SSam Ravnborg	---help---
1253506f1d07SSam Ravnborg	  Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1254506f1d07SSam Ravnborg	  However, the address space of 32-bit x86 processors is only 4
1255506f1d07SSam Ravnborg	  Gigabytes large. That means that, if you have a large amount of
1256506f1d07SSam Ravnborg	  physical memory, not all of it can be "permanently mapped" by the
1257506f1d07SSam Ravnborg	  kernel. The physical memory that's not permanently mapped is called
1258506f1d07SSam Ravnborg	  "high memory".
1259506f1d07SSam Ravnborg
1260506f1d07SSam Ravnborg	  If you are compiling a kernel which will never run on a machine with
1261506f1d07SSam Ravnborg	  more than 1 Gigabyte total physical RAM, answer "off" here (default
1262506f1d07SSam Ravnborg	  choice and suitable for most users). This will result in a "3GB/1GB"
1263506f1d07SSam Ravnborg	  split: 3GB are mapped so that each process sees a 3GB virtual memory
1264506f1d07SSam Ravnborg	  space and the remaining part of the 4GB virtual memory space is used
1265506f1d07SSam Ravnborg	  by the kernel to permanently map as much physical memory as
1266506f1d07SSam Ravnborg	  possible.
1267506f1d07SSam Ravnborg
1268506f1d07SSam Ravnborg	  If the machine has between 1 and 4 Gigabytes physical RAM, then
1269506f1d07SSam Ravnborg	  answer "4GB" here.
1270506f1d07SSam Ravnborg
1271506f1d07SSam Ravnborg	  If more than 4 Gigabytes is used then answer "64GB" here. This
1272506f1d07SSam Ravnborg	  selection turns Intel PAE (Physical Address Extension) mode on.
1273506f1d07SSam Ravnborg	  PAE implements 3-level paging on IA32 processors. PAE is fully
1274506f1d07SSam Ravnborg	  supported by Linux, PAE mode is implemented on all recent Intel
1275506f1d07SSam Ravnborg	  processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1276506f1d07SSam Ravnborg	  then the kernel will not boot on CPUs that don't support PAE!
1277506f1d07SSam Ravnborg
1278506f1d07SSam Ravnborg	  The actual amount of total physical memory will either be
1279506f1d07SSam Ravnborg	  auto detected or can be forced by using a kernel command line option
1280506f1d07SSam Ravnborg	  such as "mem=256M". (Try "man bootparam" or see the documentation of
1281506f1d07SSam Ravnborg	  your boot loader (lilo or loadlin) about how to pass options to the
1282506f1d07SSam Ravnborg	  kernel at boot time.)
1283506f1d07SSam Ravnborg
1284506f1d07SSam Ravnborg	  If unsure, say "off".
1285506f1d07SSam Ravnborg
1286506f1d07SSam Ravnborgconfig HIGHMEM4G
1287506f1d07SSam Ravnborg	bool "4GB"
12888f9ca475SIngo Molnar	---help---
1289506f1d07SSam Ravnborg	  Select this if you have a 32-bit processor and between 1 and 4
1290506f1d07SSam Ravnborg	  gigabytes of physical RAM.
1291506f1d07SSam Ravnborg
1292506f1d07SSam Ravnborgconfig HIGHMEM64G
1293506f1d07SSam Ravnborg	bool "64GB"
1294eb068e78SH. Peter Anvin	depends on !M486
1295506f1d07SSam Ravnborg	select X86_PAE
12968f9ca475SIngo Molnar	---help---
1297506f1d07SSam Ravnborg	  Select this if you have a 32-bit processor and more than 4
1298506f1d07SSam Ravnborg	  gigabytes of physical RAM.
1299506f1d07SSam Ravnborg
1300506f1d07SSam Ravnborgendchoice
1301506f1d07SSam Ravnborg
1302506f1d07SSam Ravnborgchoice
13036a108a14SDavid Rientjes	prompt "Memory split" if EXPERT
1304506f1d07SSam Ravnborg	default VMSPLIT_3G
1305506f1d07SSam Ravnborg	depends on X86_32
13068f9ca475SIngo Molnar	---help---
1307506f1d07SSam Ravnborg	  Select the desired split between kernel and user memory.
1308506f1d07SSam Ravnborg
1309506f1d07SSam Ravnborg	  If the address range available to the kernel is less than the
1310506f1d07SSam Ravnborg	  physical memory installed, the remaining memory will be available
1311506f1d07SSam Ravnborg	  as "high memory". Accessing high memory is a little more costly
1312506f1d07SSam Ravnborg	  than low memory, as it needs to be mapped into the kernel first.
1313506f1d07SSam Ravnborg	  Note that increasing the kernel address space limits the range
1314506f1d07SSam Ravnborg	  available to user programs, making the address space there
1315506f1d07SSam Ravnborg	  tighter.  Selecting anything other than the default 3G/1G split
1316506f1d07SSam Ravnborg	  will also likely make your kernel incompatible with binary-only
1317506f1d07SSam Ravnborg	  kernel modules.
1318506f1d07SSam Ravnborg
1319506f1d07SSam Ravnborg	  If you are not absolutely sure what you are doing, leave this
1320506f1d07SSam Ravnborg	  option alone!
1321506f1d07SSam Ravnborg
1322506f1d07SSam Ravnborg	config VMSPLIT_3G
1323506f1d07SSam Ravnborg		bool "3G/1G user/kernel split"
1324506f1d07SSam Ravnborg	config VMSPLIT_3G_OPT
1325506f1d07SSam Ravnborg		depends on !X86_PAE
1326506f1d07SSam Ravnborg		bool "3G/1G user/kernel split (for full 1G low memory)"
1327506f1d07SSam Ravnborg	config VMSPLIT_2G
1328506f1d07SSam Ravnborg		bool "2G/2G user/kernel split"
1329506f1d07SSam Ravnborg	config VMSPLIT_2G_OPT
1330506f1d07SSam Ravnborg		depends on !X86_PAE
1331506f1d07SSam Ravnborg		bool "2G/2G user/kernel split (for full 2G low memory)"
1332506f1d07SSam Ravnborg	config VMSPLIT_1G
1333506f1d07SSam Ravnborg		bool "1G/3G user/kernel split"
1334506f1d07SSam Ravnborgendchoice
1335506f1d07SSam Ravnborg
1336506f1d07SSam Ravnborgconfig PAGE_OFFSET
1337506f1d07SSam Ravnborg	hex
1338506f1d07SSam Ravnborg	default 0xB0000000 if VMSPLIT_3G_OPT
1339506f1d07SSam Ravnborg	default 0x80000000 if VMSPLIT_2G
1340506f1d07SSam Ravnborg	default 0x78000000 if VMSPLIT_2G_OPT
1341506f1d07SSam Ravnborg	default 0x40000000 if VMSPLIT_1G
1342506f1d07SSam Ravnborg	default 0xC0000000
1343506f1d07SSam Ravnborg	depends on X86_32
1344506f1d07SSam Ravnborg
1345506f1d07SSam Ravnborgconfig HIGHMEM
13463c2362e6SHarvey Harrison	def_bool y
1347506f1d07SSam Ravnborg	depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1348506f1d07SSam Ravnborg
1349506f1d07SSam Ravnborgconfig X86_PAE
13509ba16087SJan Beulich	bool "PAE (Physical Address Extension) Support"
1351506f1d07SSam Ravnborg	depends on X86_32 && !HIGHMEM4G
13529d99c712SChristian Melki	select SWIOTLB
13538f9ca475SIngo Molnar	---help---
1354506f1d07SSam Ravnborg	  PAE is required for NX support, and furthermore enables
1355506f1d07SSam Ravnborg	  larger swapspace support for non-overcommit purposes. It
1356506f1d07SSam Ravnborg	  has the cost of more pagetable lookup overhead, and also
1357506f1d07SSam Ravnborg	  consumes more pagetable space per process.
1358506f1d07SSam Ravnborg
1359600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT
13603120e25eSJan Beulich	def_bool y
13613120e25eSJan Beulich	depends on X86_64 || X86_PAE
1362600715dcSJeremy Fitzhardinge
136366f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT
13643120e25eSJan Beulich	def_bool y
13653120e25eSJan Beulich	depends on X86_64 || HIGHMEM64G
136666f2b061SFUJITA Tomonori
136710971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES
1368e5008abeSLuis R. Rodriguez	def_bool y
1369e5008abeSLuis R. Rodriguez	depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
13708f9ca475SIngo Molnar	---help---
137110971ab2SIngo Molnar	  Certain kernel features effectively disable kernel
137210971ab2SIngo Molnar	  linear 1 GB mappings (even if the CPU otherwise
137310971ab2SIngo Molnar	  supports them), so don't confuse the user by printing
137410971ab2SIngo Molnar	  that we have them enabled.
13759e899816SNick Piggin
1376506f1d07SSam Ravnborg# Common NUMA Features
1377506f1d07SSam Ravnborgconfig NUMA
1378fd51b2d7SKOSAKI Motohiro	bool "Numa Memory Allocation and Scheduler Support"
1379506f1d07SSam Ravnborg	depends on SMP
1380b5660ba7SH. Peter Anvin	depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1381b5660ba7SH. Peter Anvin	default y if X86_BIGSMP
13828f9ca475SIngo Molnar	---help---
1383506f1d07SSam Ravnborg	  Enable NUMA (Non Uniform Memory Access) support.
1384fd51b2d7SKOSAKI Motohiro
1385506f1d07SSam Ravnborg	  The kernel will try to allocate memory used by a CPU on the
1386506f1d07SSam Ravnborg	  local memory controller of the CPU and add some more
1387506f1d07SSam Ravnborg	  NUMA awareness to the kernel.
1388506f1d07SSam Ravnborg
1389c280ea5eSIngo Molnar	  For 64-bit this is recommended if the system is Intel Core i7
1390fd51b2d7SKOSAKI Motohiro	  (or later), AMD Opteron, or EM64T NUMA.
1391fd51b2d7SKOSAKI Motohiro
1392b5660ba7SH. Peter Anvin	  For 32-bit this is only needed if you boot a 32-bit
13937cf6c945SDavid Rientjes	  kernel on a 64-bit NUMA platform.
1394fd51b2d7SKOSAKI Motohiro
1395fd51b2d7SKOSAKI Motohiro	  Otherwise, you should say N.
1396506f1d07SSam Ravnborg
1397eec1d4faSHans Rosenfeldconfig AMD_NUMA
13983c2362e6SHarvey Harrison	def_bool y
13993c2362e6SHarvey Harrison	prompt "Old style AMD Opteron NUMA detection"
14005da0ef9aSTejun Heo	depends on X86_64 && NUMA && PCI
14018f9ca475SIngo Molnar	---help---
1402eec1d4faSHans Rosenfeld	  Enable AMD NUMA node topology detection.  You should say Y here if
1403eec1d4faSHans Rosenfeld	  you have a multi processor AMD system. This uses an old method to
1404eec1d4faSHans Rosenfeld	  read the NUMA configuration directly from the builtin Northbridge
1405eec1d4faSHans Rosenfeld	  of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1406eec1d4faSHans Rosenfeld	  which also takes priority if both are compiled in.
1407506f1d07SSam Ravnborg
1408506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA
14093c2362e6SHarvey Harrison	def_bool y
14103c2362e6SHarvey Harrison	prompt "ACPI NUMA detection"
1411506f1d07SSam Ravnborg	depends on X86_64 && NUMA && ACPI && PCI
1412506f1d07SSam Ravnborg	select ACPI_NUMA
14138f9ca475SIngo Molnar	---help---
1414506f1d07SSam Ravnborg	  Enable ACPI SRAT based node topology detection.
1415506f1d07SSam Ravnborg
14166ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span
14176ec6e0d9SSuresh Siddha# other nodes.  Even though a pfn is valid and
14186ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not
14196ec6e0d9SSuresh Siddha# reside on that node.  See memmap_init_zone()
14206ec6e0d9SSuresh Siddha# for details.
14216ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES
14226ec6e0d9SSuresh Siddha	def_bool y
14236ec6e0d9SSuresh Siddha	depends on X86_64_ACPI_NUMA
14246ec6e0d9SSuresh Siddha
1425506f1d07SSam Ravnborgconfig NUMA_EMU
1426506f1d07SSam Ravnborg	bool "NUMA emulation"
14271b7e03efSTejun Heo	depends on NUMA
14288f9ca475SIngo Molnar	---help---
1429506f1d07SSam Ravnborg	  Enable NUMA emulation. A flat machine will be split
1430506f1d07SSam Ravnborg	  into virtual nodes when booted with "numa=fake=N", where N is the
1431506f1d07SSam Ravnborg	  number of nodes. This is only useful for debugging.
1432506f1d07SSam Ravnborg
1433506f1d07SSam Ravnborgconfig NODES_SHIFT
1434d25e26b6SLinus Torvalds	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
143551591e31SDavid Rientjes	range 1 10
143651591e31SDavid Rientjes	default "10" if MAXSMP
1437506f1d07SSam Ravnborg	default "6" if X86_64
1438506f1d07SSam Ravnborg	default "3"
1439506f1d07SSam Ravnborg	depends on NEED_MULTIPLE_NODES
14408f9ca475SIngo Molnar	---help---
14411184dc2fSMike Travis	  Specify the maximum number of NUMA Nodes available on the target
1442692105b8SMatt LaPlante	  system.  Increases memory reserved to accommodate various tables.
1443506f1d07SSam Ravnborg
1444506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT
14453c2362e6SHarvey Harrison	def_bool y
1446506f1d07SSam Ravnborg	depends on X86_32 && DISCONTIGMEM
1447506f1d07SSam Ravnborg
1448506f1d07SSam Ravnborgconfig NEED_NODE_MEMMAP_SIZE
14493c2362e6SHarvey Harrison	def_bool y
1450506f1d07SSam Ravnborg	depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1451506f1d07SSam Ravnborg
1452506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE
1453506f1d07SSam Ravnborg	def_bool y
14543b16651fSTejun Heo	depends on X86_32 && !NUMA
1455506f1d07SSam Ravnborg
1456506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE
1457506f1d07SSam Ravnborg	def_bool y
1458b263295dSChristoph Lameter	depends on NUMA && X86_32
1459506f1d07SSam Ravnborg
1460506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT
1461506f1d07SSam Ravnborg	def_bool y
1462b263295dSChristoph Lameter	depends on NUMA && X86_32
1463b263295dSChristoph Lameter
1464506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE
1465506f1d07SSam Ravnborg	def_bool y
14666ea30386SKees Cook	depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1467506f1d07SSam Ravnborg	select SPARSEMEM_STATIC if X86_32
1468506f1d07SSam Ravnborg	select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1469506f1d07SSam Ravnborg
14703b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT
14713b16651fSTejun Heo	def_bool y
14723b16651fSTejun Heo	depends on X86_64
14733b16651fSTejun Heo
1474506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL
1475506f1d07SSam Ravnborg	def_bool y
1476b263295dSChristoph Lameter	depends on ARCH_SPARSEMEM_ENABLE
1477506f1d07SSam Ravnborg
1478506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE
1479a0842b70SToshi Kani	bool "Enable sysfs memory/probe interface"
14803120e25eSJan Beulich	depends on X86_64 && MEMORY_HOTPLUG
1481a0842b70SToshi Kani	help
1482a0842b70SToshi Kani	  This option enables a sysfs memory/probe interface for testing.
1483a0842b70SToshi Kani	  See Documentation/memory-hotplug.txt for more information.
1484a0842b70SToshi Kani	  If you are unsure how to answer this question, answer N.
1485506f1d07SSam Ravnborg
14863b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT
14873b16651fSTejun Heo	def_bool y
14883b16651fSTejun Heo	depends on X86_64 && PROC_KCORE
14893b16651fSTejun Heo
1490a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE
1491a29815a3SAvi Kivity       hex
1492a29815a3SAvi Kivity       default 0 if X86_32
1493a29815a3SAvi Kivity       default 0xdead000000000000 if X86_64
1494a29815a3SAvi Kivity
1495506f1d07SSam Ravnborgsource "mm/Kconfig"
1496506f1d07SSam Ravnborg
14977a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE
14987a67832cSDan Williams	bool
14997a67832cSDan Williams
1500ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY
15017a67832cSDan Williams	tristate "Support non-standard NVDIMMs and ADR protected memory"
15029f53f9faSDan Williams	depends on PHYS_ADDR_T_64BIT
15039f53f9faSDan Williams	depends on BLK_DEV
15047a67832cSDan Williams	select X86_PMEM_LEGACY_DEVICE
15059f53f9faSDan Williams	select LIBNVDIMM
1506ec776ef6SChristoph Hellwig	help
1507ec776ef6SChristoph Hellwig	  Treat memory marked using the non-standard e820 type of 12 as used
1508ec776ef6SChristoph Hellwig	  by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1509ec776ef6SChristoph Hellwig	  The kernel will offer these regions to the 'pmem' driver so
1510ec776ef6SChristoph Hellwig	  they can be used for persistent storage.
1511ec776ef6SChristoph Hellwig
1512ec776ef6SChristoph Hellwig	  Say Y if unsure.
1513ec776ef6SChristoph Hellwig
1514506f1d07SSam Ravnborgconfig HIGHPTE
1515506f1d07SSam Ravnborg	bool "Allocate 3rd-level pagetables from highmem"
15166fc108a0SJan Beulich	depends on HIGHMEM
15178f9ca475SIngo Molnar	---help---
1518506f1d07SSam Ravnborg	  The VM uses one page table entry for each page of physical memory.
1519506f1d07SSam Ravnborg	  For systems with a lot of RAM, this can be wasteful of precious
1520506f1d07SSam Ravnborg	  low memory.  Setting this option will put user-space page table
1521506f1d07SSam Ravnborg	  entries in high memory.
1522506f1d07SSam Ravnborg
15239f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION
15249f077871SJeremy Fitzhardinge	bool "Check for low memory corruption"
15258f9ca475SIngo Molnar	---help---
15269f077871SJeremy Fitzhardinge	  Periodically check for memory corruption in low memory, which
15279f077871SJeremy Fitzhardinge	  is suspected to be caused by BIOS.  Even when enabled in the
15289f077871SJeremy Fitzhardinge	  configuration, it is disabled at runtime.  Enable it by
15299f077871SJeremy Fitzhardinge	  setting "memory_corruption_check=1" on the kernel command
15309f077871SJeremy Fitzhardinge	  line.  By default it scans the low 64k of memory every 60
15319f077871SJeremy Fitzhardinge	  seconds; see the memory_corruption_check_size and
15329f077871SJeremy Fitzhardinge	  memory_corruption_check_period parameters in
15339f077871SJeremy Fitzhardinge	  Documentation/kernel-parameters.txt to adjust this.
15349f077871SJeremy Fitzhardinge
15359f077871SJeremy Fitzhardinge	  When enabled with the default parameters, this option has
15369f077871SJeremy Fitzhardinge	  almost no overhead, as it reserves a relatively small amount
15379f077871SJeremy Fitzhardinge	  of memory and scans it infrequently.  It both detects corruption
15389f077871SJeremy Fitzhardinge	  and prevents it from affecting the running system.
15399f077871SJeremy Fitzhardinge
15409f077871SJeremy Fitzhardinge	  It is, however, intended as a diagnostic tool; if repeatable
15419f077871SJeremy Fitzhardinge	  BIOS-originated corruption always affects the same memory,
15429f077871SJeremy Fitzhardinge	  you can use memmap= to prevent the kernel from using that
15439f077871SJeremy Fitzhardinge	  memory.
15449f077871SJeremy Fitzhardinge
1545c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1546c885df50SJeremy Fitzhardinge	bool "Set the default setting of memory_corruption_check"
1547c885df50SJeremy Fitzhardinge	depends on X86_CHECK_BIOS_CORRUPTION
1548c885df50SJeremy Fitzhardinge	default y
15498f9ca475SIngo Molnar	---help---
1550c885df50SJeremy Fitzhardinge	  Set whether the default state of memory_corruption_check is
1551c885df50SJeremy Fitzhardinge	  on or off.
1552c885df50SJeremy Fitzhardinge
15539ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW
1554d0cd7425SH. Peter Anvin	int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1555d0cd7425SH. Peter Anvin	default 64
1556d0cd7425SH. Peter Anvin	range 4 640
15578f9ca475SIngo Molnar	---help---
1558d0cd7425SH. Peter Anvin	  Specify the amount of low memory to reserve for the BIOS.
1559fc381519SIngo Molnar
1560d0cd7425SH. Peter Anvin	  The first page contains BIOS data structures that the kernel
1561d0cd7425SH. Peter Anvin	  must not use, so that page must always be reserved.
1562fc381519SIngo Molnar
1563d0cd7425SH. Peter Anvin	  By default we reserve the first 64K of physical RAM, as a
1564d0cd7425SH. Peter Anvin	  number of BIOSes are known to corrupt that memory range
1565d0cd7425SH. Peter Anvin	  during events such as suspend/resume or monitor cable
1566d0cd7425SH. Peter Anvin	  insertion, so it must not be used by the kernel.
1567fc381519SIngo Molnar
1568d0cd7425SH. Peter Anvin	  You can set this to 4 if you are absolutely sure that you
1569d0cd7425SH. Peter Anvin	  trust the BIOS to get all its memory reservations and usages
1570d0cd7425SH. Peter Anvin	  right.  If you know your BIOS have problems beyond the
1571d0cd7425SH. Peter Anvin	  default 64K area, you can set this to 640 to avoid using the
1572d0cd7425SH. Peter Anvin	  entire low memory range.
1573d0cd7425SH. Peter Anvin
1574d0cd7425SH. Peter Anvin	  If you have doubts about the BIOS (e.g. suspend/resume does
1575d0cd7425SH. Peter Anvin	  not work or there's kernel crashes after certain hardware
1576d0cd7425SH. Peter Anvin	  hotplug events) then you might want to enable
1577d0cd7425SH. Peter Anvin	  X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1578d0cd7425SH. Peter Anvin	  typical corruption patterns.
1579d0cd7425SH. Peter Anvin
1580d0cd7425SH. Peter Anvin	  Leave this to the default value of 64 if you are unsure.
1581fc381519SIngo Molnar
1582506f1d07SSam Ravnborgconfig MATH_EMULATION
1583506f1d07SSam Ravnborg	bool
1584a5b9e5a2SAndy Lutomirski	depends on MODIFY_LDT_SYSCALL
1585506f1d07SSam Ravnborg	prompt "Math emulation" if X86_32
1586506f1d07SSam Ravnborg	---help---
1587506f1d07SSam Ravnborg	  Linux can emulate a math coprocessor (used for floating point
1588506f1d07SSam Ravnborg	  operations) if you don't have one. 486DX and Pentium processors have
1589506f1d07SSam Ravnborg	  a math coprocessor built in, 486SX and 386 do not, unless you added
1590506f1d07SSam Ravnborg	  a 487DX or 387, respectively. (The messages during boot time can
1591506f1d07SSam Ravnborg	  give you some hints here ["man dmesg"].) Everyone needs either a
1592506f1d07SSam Ravnborg	  coprocessor or this emulation.
1593506f1d07SSam Ravnborg
1594506f1d07SSam Ravnborg	  If you don't have a math coprocessor, you need to say Y here; if you
1595506f1d07SSam Ravnborg	  say Y here even though you have a coprocessor, the coprocessor will
1596506f1d07SSam Ravnborg	  be used nevertheless. (This behavior can be changed with the kernel
1597506f1d07SSam Ravnborg	  command line option "no387", which comes handy if your coprocessor
1598506f1d07SSam Ravnborg	  is broken. Try "man bootparam" or see the documentation of your boot
1599506f1d07SSam Ravnborg	  loader (lilo or loadlin) about how to pass options to the kernel at
1600506f1d07SSam Ravnborg	  boot time.) This means that it is a good idea to say Y here if you
1601506f1d07SSam Ravnborg	  intend to use this kernel on different machines.
1602506f1d07SSam Ravnborg
1603506f1d07SSam Ravnborg	  More information about the internals of the Linux math coprocessor
1604506f1d07SSam Ravnborg	  emulation can be found in <file:arch/x86/math-emu/README>.
1605506f1d07SSam Ravnborg
1606506f1d07SSam Ravnborg	  If you are not sure, say Y; apart from resulting in a 66 KB bigger
1607506f1d07SSam Ravnborg	  kernel, it won't hurt.
1608506f1d07SSam Ravnborg
1609506f1d07SSam Ravnborgconfig MTRR
16106fc108a0SJan Beulich	def_bool y
16116a108a14SDavid Rientjes	prompt "MTRR (Memory Type Range Register) support" if EXPERT
1612506f1d07SSam Ravnborg	---help---
1613506f1d07SSam Ravnborg	  On Intel P6 family processors (Pentium Pro, Pentium II and later)
1614506f1d07SSam Ravnborg	  the Memory Type Range Registers (MTRRs) may be used to control
1615506f1d07SSam Ravnborg	  processor access to memory ranges. This is most useful if you have
1616506f1d07SSam Ravnborg	  a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1617506f1d07SSam Ravnborg	  allows bus write transfers to be combined into a larger transfer
1618506f1d07SSam Ravnborg	  before bursting over the PCI/AGP bus. This can increase performance
1619506f1d07SSam Ravnborg	  of image write operations 2.5 times or more. Saying Y here creates a
1620506f1d07SSam Ravnborg	  /proc/mtrr file which may be used to manipulate your processor's
1621506f1d07SSam Ravnborg	  MTRRs. Typically the X server should use this.
1622506f1d07SSam Ravnborg
1623506f1d07SSam Ravnborg	  This code has a reasonably generic interface so that similar
1624506f1d07SSam Ravnborg	  control registers on other processors can be easily supported
1625506f1d07SSam Ravnborg	  as well:
1626506f1d07SSam Ravnborg
1627506f1d07SSam Ravnborg	  The Cyrix 6x86, 6x86MX and M II processors have Address Range
1628506f1d07SSam Ravnborg	  Registers (ARRs) which provide a similar functionality to MTRRs. For
1629506f1d07SSam Ravnborg	  these, the ARRs are used to emulate the MTRRs.
1630506f1d07SSam Ravnborg	  The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1631506f1d07SSam Ravnborg	  MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1632506f1d07SSam Ravnborg	  write-combining. All of these processors are supported by this code
1633506f1d07SSam Ravnborg	  and it makes sense to say Y here if you have one of them.
1634506f1d07SSam Ravnborg
1635506f1d07SSam Ravnborg	  Saying Y here also fixes a problem with buggy SMP BIOSes which only
1636506f1d07SSam Ravnborg	  set the MTRRs for the boot CPU and not for the secondary CPUs. This
1637506f1d07SSam Ravnborg	  can lead to all sorts of problems, so it's good to say Y here.
1638506f1d07SSam Ravnborg
1639506f1d07SSam Ravnborg	  You can safely say Y even if your machine doesn't have MTRRs, you'll
1640506f1d07SSam Ravnborg	  just add about 9 KB to your kernel.
1641506f1d07SSam Ravnborg
16427225e751SRandy Dunlap	  See <file:Documentation/x86/mtrr.txt> for more information.
1643506f1d07SSam Ravnborg
164495ffa243SYinghai Luconfig MTRR_SANITIZER
16452ffb3501SYinghai Lu	def_bool y
164695ffa243SYinghai Lu	prompt "MTRR cleanup support"
164795ffa243SYinghai Lu	depends on MTRR
16488f9ca475SIngo Molnar	---help---
1649aba3728cSThomas Gleixner	  Convert MTRR layout from continuous to discrete, so X drivers can
1650aba3728cSThomas Gleixner	  add writeback entries.
165195ffa243SYinghai Lu
1652aba3728cSThomas Gleixner	  Can be disabled with disable_mtrr_cleanup on the kernel command line.
1653692105b8SMatt LaPlante	  The largest mtrr entry size for a continuous block can be set with
1654aba3728cSThomas Gleixner	  mtrr_chunk_size.
165595ffa243SYinghai Lu
16562ffb3501SYinghai Lu	  If unsure, say Y.
165795ffa243SYinghai Lu
165895ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT
1659f5098d62SYinghai Lu	int "MTRR cleanup enable value (0-1)"
1660f5098d62SYinghai Lu	range 0 1
1661f5098d62SYinghai Lu	default "0"
166295ffa243SYinghai Lu	depends on MTRR_SANITIZER
16638f9ca475SIngo Molnar	---help---
1664f5098d62SYinghai Lu	  Enable mtrr cleanup default value
166595ffa243SYinghai Lu
166612031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
166712031a62SYinghai Lu	int "MTRR cleanup spare reg num (0-7)"
166812031a62SYinghai Lu	range 0 7
166912031a62SYinghai Lu	default "1"
167012031a62SYinghai Lu	depends on MTRR_SANITIZER
16718f9ca475SIngo Molnar	---help---
167212031a62SYinghai Lu	  mtrr cleanup spare entries default, it can be changed via
1673aba3728cSThomas Gleixner	  mtrr_spare_reg_nr=N on the kernel command line.
167412031a62SYinghai Lu
16752e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT
16766fc108a0SJan Beulich	def_bool y
16776a108a14SDavid Rientjes	prompt "x86 PAT support" if EXPERT
16782a8a2719SIngo Molnar	depends on MTRR
16798f9ca475SIngo Molnar	---help---
16802e5d9c85Svenkatesh.pallipadi@intel.com	  Use PAT attributes to setup page level cache control.
1681042b78e4SVenki Pallipadi
16822e5d9c85Svenkatesh.pallipadi@intel.com	  PATs are the modern equivalents of MTRRs and are much more
16832e5d9c85Svenkatesh.pallipadi@intel.com	  flexible than MTRRs.
16842e5d9c85Svenkatesh.pallipadi@intel.com
16852e5d9c85Svenkatesh.pallipadi@intel.com	  Say N here if you see bootup problems (boot crash, boot hang,
1686042b78e4SVenki Pallipadi	  spontaneous reboots) or a non-working video driver.
16872e5d9c85Svenkatesh.pallipadi@intel.com
16882e5d9c85Svenkatesh.pallipadi@intel.com	  If unsure, say Y.
16892e5d9c85Svenkatesh.pallipadi@intel.com
169046cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED
169146cf98cdSVenkatesh Pallipadi	def_bool y
169246cf98cdSVenkatesh Pallipadi	depends on X86_PAT
169346cf98cdSVenkatesh Pallipadi
1694628c6246SH. Peter Anvinconfig ARCH_RANDOM
1695628c6246SH. Peter Anvin	def_bool y
1696628c6246SH. Peter Anvin	prompt "x86 architectural random number generator" if EXPERT
1697628c6246SH. Peter Anvin	---help---
1698628c6246SH. Peter Anvin	  Enable the x86 architectural RDRAND instruction
1699628c6246SH. Peter Anvin	  (Intel Bull Mountain technology) to generate random numbers.
1700628c6246SH. Peter Anvin	  If supported, this is a high bandwidth, cryptographically
1701628c6246SH. Peter Anvin	  secure hardware random number generator.
1702628c6246SH. Peter Anvin
170351ae4a2dSH. Peter Anvinconfig X86_SMAP
170451ae4a2dSH. Peter Anvin	def_bool y
170551ae4a2dSH. Peter Anvin	prompt "Supervisor Mode Access Prevention" if EXPERT
170651ae4a2dSH. Peter Anvin	---help---
170751ae4a2dSH. Peter Anvin	  Supervisor Mode Access Prevention (SMAP) is a security
170851ae4a2dSH. Peter Anvin	  feature in newer Intel processors.  There is a small
170951ae4a2dSH. Peter Anvin	  performance cost if this enabled and turned on; there is
171051ae4a2dSH. Peter Anvin	  also a small increase in the kernel size if this is enabled.
171151ae4a2dSH. Peter Anvin
171251ae4a2dSH. Peter Anvin	  If unsure, say Y.
171351ae4a2dSH. Peter Anvin
171472e9b5feSDave Hansenconfig X86_INTEL_MPX
171572e9b5feSDave Hansen	prompt "Intel MPX (Memory Protection Extensions)"
171672e9b5feSDave Hansen	def_bool n
171772e9b5feSDave Hansen	depends on CPU_SUP_INTEL
171872e9b5feSDave Hansen	---help---
171972e9b5feSDave Hansen	  MPX provides hardware features that can be used in
172072e9b5feSDave Hansen	  conjunction with compiler-instrumented code to check
172172e9b5feSDave Hansen	  memory references.  It is designed to detect buffer
172272e9b5feSDave Hansen	  overflow or underflow bugs.
172372e9b5feSDave Hansen
172472e9b5feSDave Hansen	  This option enables running applications which are
172572e9b5feSDave Hansen	  instrumented or otherwise use MPX.  It does not use MPX
172672e9b5feSDave Hansen	  itself inside the kernel or to protect the kernel
172772e9b5feSDave Hansen	  against bad memory references.
172872e9b5feSDave Hansen
172972e9b5feSDave Hansen	  Enabling this option will make the kernel larger:
173072e9b5feSDave Hansen	  ~8k of kernel text and 36 bytes of data on a 64-bit
173172e9b5feSDave Hansen	  defconfig.  It adds a long to the 'mm_struct' which
173272e9b5feSDave Hansen	  will increase the kernel memory overhead of each
173372e9b5feSDave Hansen	  process and adds some branches to paths used during
173472e9b5feSDave Hansen	  exec() and munmap().
173572e9b5feSDave Hansen
173672e9b5feSDave Hansen	  For details, see Documentation/x86/intel_mpx.txt
173772e9b5feSDave Hansen
173872e9b5feSDave Hansen	  If unsure, say N.
173972e9b5feSDave Hansen
174035e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS
1741284244a9SDave Hansen	prompt "Intel Memory Protection Keys"
174235e97790SDave Hansen	def_bool y
1743284244a9SDave Hansen	# Note: only available in 64-bit mode
174435e97790SDave Hansen	depends on CPU_SUP_INTEL && X86_64
174552c8e601SIngo Molnar	select ARCH_USES_HIGH_VMA_FLAGS
174652c8e601SIngo Molnar	select ARCH_HAS_PKEYS
1747284244a9SDave Hansen	---help---
1748284244a9SDave Hansen	  Memory Protection Keys provides a mechanism for enforcing
1749284244a9SDave Hansen	  page-based protections, but without requiring modification of the
1750284244a9SDave Hansen	  page tables when an application changes protection domains.
1751284244a9SDave Hansen
1752284244a9SDave Hansen	  For details, see Documentation/x86/protection-keys.txt
1753284244a9SDave Hansen
1754284244a9SDave Hansen	  If unsure, say y.
175535e97790SDave Hansen
1756506f1d07SSam Ravnborgconfig EFI
17579ba16087SJan Beulich	bool "EFI runtime service support"
17585b83683fSHuang, Ying	depends on ACPI
1759f6ce5002SSergey Vlasov	select UCS2_STRING
1760022ee6c5SArd Biesheuvel	select EFI_RUNTIME_WRAPPERS
1761506f1d07SSam Ravnborg	---help---
17628b2cb7a8SHuang, Ying	  This enables the kernel to use EFI runtime services that are
1763506f1d07SSam Ravnborg	  available (such as the EFI variable services).
1764506f1d07SSam Ravnborg
17658b2cb7a8SHuang, Ying	  This option is only useful on systems that have EFI firmware.
17668b2cb7a8SHuang, Ying	  In addition, you should use the latest ELILO loader available
17678b2cb7a8SHuang, Ying	  at <http://elilo.sourceforge.net> in order to take advantage
17688b2cb7a8SHuang, Ying	  of EFI runtime services. However, even with this option, the
17698b2cb7a8SHuang, Ying	  resultant kernel should continue to boot on existing non-EFI
17708b2cb7a8SHuang, Ying	  platforms.
1771506f1d07SSam Ravnborg
1772291f3632SMatt Flemingconfig EFI_STUB
1773291f3632SMatt Fleming       bool "EFI stub support"
1774b16d8c23SMatt Fleming       depends on EFI && !X86_USE_3DNOW
17757b2a583aSMatt Fleming       select RELOCATABLE
1776291f3632SMatt Fleming       ---help---
1777291f3632SMatt Fleming          This kernel feature allows a bzImage to be loaded directly
1778291f3632SMatt Fleming	  by EFI firmware without the use of a bootloader.
1779291f3632SMatt Fleming
17804172fe2fSRoy Franz	  See Documentation/efi-stub.txt for more information.
17810c759662SMatt Fleming
17827d453eeeSMatt Flemingconfig EFI_MIXED
17837d453eeeSMatt Fleming	bool "EFI mixed-mode support"
17847d453eeeSMatt Fleming	depends on EFI_STUB && X86_64
17857d453eeeSMatt Fleming	---help---
17867d453eeeSMatt Fleming	   Enabling this feature allows a 64-bit kernel to be booted
17877d453eeeSMatt Fleming	   on a 32-bit firmware, provided that your CPU supports 64-bit
17887d453eeeSMatt Fleming	   mode.
17897d453eeeSMatt Fleming
17907d453eeeSMatt Fleming	   Note that it is not possible to boot a mixed-mode enabled
17917d453eeeSMatt Fleming	   kernel via the EFI boot stub - a bootloader that supports
17927d453eeeSMatt Fleming	   the EFI handover protocol must be used.
17937d453eeeSMatt Fleming
17947d453eeeSMatt Fleming	   If unsure, say N.
17957d453eeeSMatt Fleming
1796506f1d07SSam Ravnborgconfig SECCOMP
17973c2362e6SHarvey Harrison	def_bool y
17983c2362e6SHarvey Harrison	prompt "Enable seccomp to safely compute untrusted bytecode"
17998f9ca475SIngo Molnar	---help---
1800506f1d07SSam Ravnborg	  This kernel feature is useful for number crunching applications
1801506f1d07SSam Ravnborg	  that may need to compute untrusted bytecode during their
1802506f1d07SSam Ravnborg	  execution. By using pipes or other transports made available to
1803506f1d07SSam Ravnborg	  the process as file descriptors supporting the read/write
1804506f1d07SSam Ravnborg	  syscalls, it's possible to isolate those applications in
1805506f1d07SSam Ravnborg	  their own address space using seccomp. Once seccomp is
18069c0bbee8SAlexey Dobriyan	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1807506f1d07SSam Ravnborg	  and the task is only allowed to execute a few safe syscalls
1808506f1d07SSam Ravnborg	  defined by each seccomp mode.
1809506f1d07SSam Ravnborg
1810506f1d07SSam Ravnborg	  If unsure, say Y. Only embedded should say N here.
1811506f1d07SSam Ravnborg
1812506f1d07SSam Ravnborgsource kernel/Kconfig.hz
1813506f1d07SSam Ravnborg
1814506f1d07SSam Ravnborgconfig KEXEC
1815506f1d07SSam Ravnborg	bool "kexec system call"
18162965faa5SDave Young	select KEXEC_CORE
18178f9ca475SIngo Molnar	---help---
1818506f1d07SSam Ravnborg	  kexec is a system call that implements the ability to shutdown your
1819506f1d07SSam Ravnborg	  current kernel, and to start another kernel.  It is like a reboot
1820506f1d07SSam Ravnborg	  but it is independent of the system firmware.   And like a reboot
1821506f1d07SSam Ravnborg	  you can start any kernel with it, not just Linux.
1822506f1d07SSam Ravnborg
1823506f1d07SSam Ravnborg	  The name comes from the similarity to the exec system call.
1824506f1d07SSam Ravnborg
1825506f1d07SSam Ravnborg	  It is an ongoing process to be certain the hardware in a machine
1826506f1d07SSam Ravnborg	  is properly shutdown, so do not be surprised if this code does not
1827bf220695SGeert Uytterhoeven	  initially work for you.  As of this writing the exact hardware
1828bf220695SGeert Uytterhoeven	  interface is strongly in flux, so no good recommendation can be
1829bf220695SGeert Uytterhoeven	  made.
1830506f1d07SSam Ravnborg
183174ca317cSVivek Goyalconfig KEXEC_FILE
183274ca317cSVivek Goyal	bool "kexec file based system call"
18332965faa5SDave Young	select KEXEC_CORE
183474ca317cSVivek Goyal	select BUILD_BIN2C
183574ca317cSVivek Goyal	depends on X86_64
183674ca317cSVivek Goyal	depends on CRYPTO=y
183774ca317cSVivek Goyal	depends on CRYPTO_SHA256=y
183874ca317cSVivek Goyal	---help---
183974ca317cSVivek Goyal	  This is new version of kexec system call. This system call is
184074ca317cSVivek Goyal	  file based and takes file descriptors as system call argument
184174ca317cSVivek Goyal	  for kernel and initramfs as opposed to list of segments as
184274ca317cSVivek Goyal	  accepted by previous system call.
184374ca317cSVivek Goyal
18448e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG
18458e7d8381SVivek Goyal	bool "Verify kernel signature during kexec_file_load() syscall"
184674ca317cSVivek Goyal	depends on KEXEC_FILE
18478e7d8381SVivek Goyal	---help---
18488e7d8381SVivek Goyal	  This option makes kernel signature verification mandatory for
1849d8eb8940SBorislav Petkov	  the kexec_file_load() syscall.
18508e7d8381SVivek Goyal
1851d8eb8940SBorislav Petkov	  In addition to that option, you need to enable signature
1852d8eb8940SBorislav Petkov	  verification for the corresponding kernel image type being
1853d8eb8940SBorislav Petkov	  loaded in order for this to work.
18548e7d8381SVivek Goyal
18558e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG
18568e7d8381SVivek Goyal	bool "Enable bzImage signature verification support"
18578e7d8381SVivek Goyal	depends on KEXEC_VERIFY_SIG
18588e7d8381SVivek Goyal	depends on SIGNED_PE_FILE_VERIFICATION
18598e7d8381SVivek Goyal	select SYSTEM_TRUSTED_KEYRING
18608e7d8381SVivek Goyal	---help---
18618e7d8381SVivek Goyal	  Enable bzImage signature verification support.
18628e7d8381SVivek Goyal
1863506f1d07SSam Ravnborgconfig CRASH_DUMP
186404b69447SPavel Machek	bool "kernel crash dumps"
1865506f1d07SSam Ravnborg	depends on X86_64 || (X86_32 && HIGHMEM)
18668f9ca475SIngo Molnar	---help---
1867506f1d07SSam Ravnborg	  Generate crash dump after being started by kexec.
1868506f1d07SSam Ravnborg	  This should be normally only set in special crash dump kernels
1869506f1d07SSam Ravnborg	  which are loaded in the main kernel with kexec-tools into
1870506f1d07SSam Ravnborg	  a specially reserved region and then later executed after
1871506f1d07SSam Ravnborg	  a crash by kdump/kexec. The crash dump kernel must be compiled
1872506f1d07SSam Ravnborg	  to a memory address not used by the main kernel or BIOS using
1873506f1d07SSam Ravnborg	  PHYSICAL_START, or it must be built as a relocatable image
1874506f1d07SSam Ravnborg	  (CONFIG_RELOCATABLE=y).
1875506f1d07SSam Ravnborg	  For more details see Documentation/kdump/kdump.txt
1876506f1d07SSam Ravnborg
18773ab83521SHuang Yingconfig KEXEC_JUMP
18786ea30386SKees Cook	bool "kexec jump"
1879fee7b0d8SHuang Ying	depends on KEXEC && HIBERNATION
18808f9ca475SIngo Molnar	---help---
188189081d17SHuang Ying	  Jump between original kernel and kexeced kernel and invoke
188289081d17SHuang Ying	  code in physical address mode via KEXEC
18833ab83521SHuang Ying
1884506f1d07SSam Ravnborgconfig PHYSICAL_START
18856a108a14SDavid Rientjes	hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1886ceefccc9SH. Peter Anvin	default "0x1000000"
18878f9ca475SIngo Molnar	---help---
1888506f1d07SSam Ravnborg	  This gives the physical address where the kernel is loaded.
1889506f1d07SSam Ravnborg
1890506f1d07SSam Ravnborg	  If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1891506f1d07SSam Ravnborg	  bzImage will decompress itself to above physical address and
1892506f1d07SSam Ravnborg	  run from there. Otherwise, bzImage will run from the address where
1893506f1d07SSam Ravnborg	  it has been loaded by the boot loader and will ignore above physical
1894506f1d07SSam Ravnborg	  address.
1895506f1d07SSam Ravnborg
1896506f1d07SSam Ravnborg	  In normal kdump cases one does not have to set/change this option
1897506f1d07SSam Ravnborg	  as now bzImage can be compiled as a completely relocatable image
1898506f1d07SSam Ravnborg	  (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1899506f1d07SSam Ravnborg	  address. This option is mainly useful for the folks who don't want
1900506f1d07SSam Ravnborg	  to use a bzImage for capturing the crash dump and want to use a
1901506f1d07SSam Ravnborg	  vmlinux instead. vmlinux is not relocatable hence a kernel needs
1902506f1d07SSam Ravnborg	  to be specifically compiled to run from a specific memory area
1903506f1d07SSam Ravnborg	  (normally a reserved region) and this option comes handy.
1904506f1d07SSam Ravnborg
1905ceefccc9SH. Peter Anvin	  So if you are using bzImage for capturing the crash dump,
1906ceefccc9SH. Peter Anvin	  leave the value here unchanged to 0x1000000 and set
1907ceefccc9SH. Peter Anvin	  CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1908ceefccc9SH. Peter Anvin	  for capturing the crash dump change this value to start of
1909ceefccc9SH. Peter Anvin	  the reserved region.  In other words, it can be set based on
1910ceefccc9SH. Peter Anvin	  the "X" value as specified in the "crashkernel=YM@XM"
1911ceefccc9SH. Peter Anvin	  command line boot parameter passed to the panic-ed
1912ceefccc9SH. Peter Anvin	  kernel. Please take a look at Documentation/kdump/kdump.txt
1913ceefccc9SH. Peter Anvin	  for more details about crash dumps.
1914506f1d07SSam Ravnborg
1915506f1d07SSam Ravnborg	  Usage of bzImage for capturing the crash dump is recommended as
1916506f1d07SSam Ravnborg	  one does not have to build two kernels. Same kernel can be used
1917506f1d07SSam Ravnborg	  as production kernel and capture kernel. Above option should have
1918506f1d07SSam Ravnborg	  gone away after relocatable bzImage support is introduced. But it
1919506f1d07SSam Ravnborg	  is present because there are users out there who continue to use
1920506f1d07SSam Ravnborg	  vmlinux for dump capture. This option should go away down the
1921506f1d07SSam Ravnborg	  line.
1922506f1d07SSam Ravnborg
1923506f1d07SSam Ravnborg	  Don't change this unless you know what you are doing.
1924506f1d07SSam Ravnborg
1925506f1d07SSam Ravnborgconfig RELOCATABLE
192626717808SH. Peter Anvin	bool "Build a relocatable kernel"
192726717808SH. Peter Anvin	default y
19288f9ca475SIngo Molnar	---help---
1929506f1d07SSam Ravnborg	  This builds a kernel image that retains relocation information
1930506f1d07SSam Ravnborg	  so it can be loaded someplace besides the default 1MB.
1931506f1d07SSam Ravnborg	  The relocations tend to make the kernel binary about 10% larger,
1932506f1d07SSam Ravnborg	  but are discarded at runtime.
1933506f1d07SSam Ravnborg
1934506f1d07SSam Ravnborg	  One use is for the kexec on panic case where the recovery kernel
1935506f1d07SSam Ravnborg	  must live at a different physical address than the primary
1936506f1d07SSam Ravnborg	  kernel.
1937506f1d07SSam Ravnborg
1938506f1d07SSam Ravnborg	  Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1939506f1d07SSam Ravnborg	  it has been loaded at and the compile time physical address
19408ab3820fSKees Cook	  (CONFIG_PHYSICAL_START) is used as the minimum location.
1941506f1d07SSam Ravnborg
19428ab3820fSKees Cookconfig RANDOMIZE_BASE
1943e8581e3dSBaoquan He	bool "Randomize the address of the kernel image (KASLR)"
19448ab3820fSKees Cook	depends on RELOCATABLE
19458ab3820fSKees Cook	default n
19468ab3820fSKees Cook	---help---
1947e8581e3dSBaoquan He	  In support of Kernel Address Space Layout Randomization (KASLR),
1948e8581e3dSBaoquan He	  this randomizes the physical address at which the kernel image
1949e8581e3dSBaoquan He	  is decompressed and the virtual address where the kernel
1950e8581e3dSBaoquan He	  image is mapped, as a security feature that deters exploit
1951e8581e3dSBaoquan He	  attempts relying on knowledge of the location of kernel
1952e8581e3dSBaoquan He	  code internals.
1953e8581e3dSBaoquan He
1954ed9f007eSKees Cook	  On 64-bit, the kernel physical and virtual addresses are
1955ed9f007eSKees Cook	  randomized separately. The physical address will be anywhere
1956ed9f007eSKees Cook	  between 16MB and the top of physical memory (up to 64TB). The
1957ed9f007eSKees Cook	  virtual address will be randomized from 16MB up to 1GB (9 bits
1958ed9f007eSKees Cook	  of entropy). Note that this also reduces the memory space
1959ed9f007eSKees Cook	  available to kernel modules from 1.5GB to 1GB.
1960ed9f007eSKees Cook
1961ed9f007eSKees Cook	  On 32-bit, the kernel physical and virtual addresses are
1962ed9f007eSKees Cook	  randomized together. They will be randomized from 16MB up to
1963ed9f007eSKees Cook	  512MB (8 bits of entropy).
19648ab3820fSKees Cook
1965a653f356SKees Cook	  Entropy is generated using the RDRAND instruction if it is
1966e8581e3dSBaoquan He	  supported. If RDTSC is supported, its value is mixed into
1967e8581e3dSBaoquan He	  the entropy pool as well. If neither RDRAND nor RDTSC are
1968ed9f007eSKees Cook	  supported, then entropy is read from the i8254 timer. The
1969ed9f007eSKees Cook	  usable entropy is limited by the kernel being built using
1970ed9f007eSKees Cook	  2GB addressing, and that PHYSICAL_ALIGN must be at a
1971ed9f007eSKees Cook	  minimum of 2MB. As a result, only 10 bits of entropy are
1972ed9f007eSKees Cook	  theoretically possible, but the implementations are further
1973ed9f007eSKees Cook	  limited due to memory layouts.
1974e8581e3dSBaoquan He
1975e8581e3dSBaoquan He	  If CONFIG_HIBERNATE is also enabled, KASLR is disabled at boot
1976e8581e3dSBaoquan He	  time. To enable it, boot with "kaslr" on the kernel command
1977e8581e3dSBaoquan He	  line (which will also disable hibernation).
19788ab3820fSKees Cook
1979da2b6fb9SKees Cook	  If unsure, say N.
1980da2b6fb9SKees Cook
19818ab3820fSKees Cook# Relocation on x86 needs some additional build support
1982845adf72SH. Peter Anvinconfig X86_NEED_RELOCS
1983845adf72SH. Peter Anvin	def_bool y
19848ab3820fSKees Cook	depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1985845adf72SH. Peter Anvin
1986506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN
1987a0215061SKees Cook	hex "Alignment value to which kernel should be aligned"
19888ab3820fSKees Cook	default "0x200000"
1989a0215061SKees Cook	range 0x2000 0x1000000 if X86_32
1990a0215061SKees Cook	range 0x200000 0x1000000 if X86_64
19918f9ca475SIngo Molnar	---help---
1992506f1d07SSam Ravnborg	  This value puts the alignment restrictions on physical address
1993506f1d07SSam Ravnborg	  where kernel is loaded and run from. Kernel is compiled for an
1994506f1d07SSam Ravnborg	  address which meets above alignment restriction.
1995506f1d07SSam Ravnborg
1996506f1d07SSam Ravnborg	  If bootloader loads the kernel at a non-aligned address and
1997506f1d07SSam Ravnborg	  CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1998506f1d07SSam Ravnborg	  address aligned to above value and run from there.
1999506f1d07SSam Ravnborg
2000506f1d07SSam Ravnborg	  If bootloader loads the kernel at a non-aligned address and
2001506f1d07SSam Ravnborg	  CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2002506f1d07SSam Ravnborg	  load address and decompress itself to the address it has been
2003506f1d07SSam Ravnborg	  compiled for and run from there. The address for which kernel is
2004506f1d07SSam Ravnborg	  compiled already meets above alignment restrictions. Hence the
2005506f1d07SSam Ravnborg	  end result is that kernel runs from a physical address meeting
2006506f1d07SSam Ravnborg	  above alignment restrictions.
2007506f1d07SSam Ravnborg
2008a0215061SKees Cook	  On 32-bit this value must be a multiple of 0x2000. On 64-bit
2009a0215061SKees Cook	  this value must be a multiple of 0x200000.
2010a0215061SKees Cook
2011506f1d07SSam Ravnborg	  Don't change this unless you know what you are doing.
2012506f1d07SSam Ravnborg
20130483e1faSThomas Garnierconfig RANDOMIZE_MEMORY
20140483e1faSThomas Garnier	bool "Randomize the kernel memory sections"
20150483e1faSThomas Garnier	depends on X86_64
20160483e1faSThomas Garnier	depends on RANDOMIZE_BASE
20170483e1faSThomas Garnier	default RANDOMIZE_BASE
20180483e1faSThomas Garnier	---help---
20190483e1faSThomas Garnier	   Randomizes the base virtual address of kernel memory sections
20200483e1faSThomas Garnier	   (physical memory mapping, vmalloc & vmemmap). This security feature
20210483e1faSThomas Garnier	   makes exploits relying on predictable memory locations less reliable.
20220483e1faSThomas Garnier
20230483e1faSThomas Garnier	   The order of allocations remains unchanged. Entropy is generated in
20240483e1faSThomas Garnier	   the same way as RANDOMIZE_BASE. Current implementation in the optimal
20250483e1faSThomas Garnier	   configuration have in average 30,000 different possible virtual
20260483e1faSThomas Garnier	   addresses for each memory section.
20270483e1faSThomas Garnier
20280483e1faSThomas Garnier	   If unsure, say N.
20290483e1faSThomas Garnier
203090397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING
203190397a41SThomas Garnier	hex "Physical memory mapping padding" if EXPERT
203290397a41SThomas Garnier	depends on RANDOMIZE_MEMORY
203390397a41SThomas Garnier	default "0xa" if MEMORY_HOTPLUG
203490397a41SThomas Garnier	default "0x0"
203590397a41SThomas Garnier	range 0x1 0x40 if MEMORY_HOTPLUG
203690397a41SThomas Garnier	range 0x0 0x40
203790397a41SThomas Garnier	---help---
203890397a41SThomas Garnier	   Define the padding in terabytes added to the existing physical
203990397a41SThomas Garnier	   memory size during kernel memory randomization. It is useful
204090397a41SThomas Garnier	   for memory hotplug support but reduces the entropy available for
204190397a41SThomas Garnier	   address randomization.
204290397a41SThomas Garnier
204390397a41SThomas Garnier	   If unsure, leave at the default value.
204490397a41SThomas Garnier
2045506f1d07SSam Ravnborgconfig HOTPLUG_CPU
20467c13e6a3SDimitri Sivanich	bool "Support for hot-pluggable CPUs"
204740b31360SStephen Rothwell	depends on SMP
2048506f1d07SSam Ravnborg	---help---
20497c13e6a3SDimitri Sivanich	  Say Y here to allow turning CPUs off and on. CPUs can be
20507c13e6a3SDimitri Sivanich	  controlled through /sys/devices/system/cpu.
20517c13e6a3SDimitri Sivanich	  ( Note: power management support will enable this option
20527c13e6a3SDimitri Sivanich	    automatically on SMP systems. )
20537c13e6a3SDimitri Sivanich	  Say N if you want to disable CPU hotplug.
2054506f1d07SSam Ravnborg
205580aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0
205680aa1dffSFenghua Yu	bool "Set default setting of cpu0_hotpluggable"
205780aa1dffSFenghua Yu	default n
20582c922cd0SKees Cook	depends on HOTPLUG_CPU
205980aa1dffSFenghua Yu	---help---
206080aa1dffSFenghua Yu	  Set whether default state of cpu0_hotpluggable is on or off.
206180aa1dffSFenghua Yu
206280aa1dffSFenghua Yu	  Say Y here to enable CPU0 hotplug by default. If this switch
206380aa1dffSFenghua Yu	  is turned on, there is no need to give cpu0_hotplug kernel
206480aa1dffSFenghua Yu	  parameter and the CPU0 hotplug feature is enabled by default.
206580aa1dffSFenghua Yu
206680aa1dffSFenghua Yu	  Please note: there are two known CPU0 dependencies if you want
206780aa1dffSFenghua Yu	  to enable the CPU0 hotplug feature either by this switch or by
206880aa1dffSFenghua Yu	  cpu0_hotplug kernel parameter.
206980aa1dffSFenghua Yu
207080aa1dffSFenghua Yu	  First, resume from hibernate or suspend always starts from CPU0.
207180aa1dffSFenghua Yu	  So hibernate and suspend are prevented if CPU0 is offline.
207280aa1dffSFenghua Yu
207380aa1dffSFenghua Yu	  Second dependency is PIC interrupts always go to CPU0. CPU0 can not
207480aa1dffSFenghua Yu	  offline if any interrupt can not migrate out of CPU0. There may
207580aa1dffSFenghua Yu	  be other CPU0 dependencies.
207680aa1dffSFenghua Yu
207780aa1dffSFenghua Yu	  Please make sure the dependencies are under your control before
207880aa1dffSFenghua Yu	  you enable this feature.
207980aa1dffSFenghua Yu
208080aa1dffSFenghua Yu	  Say N if you don't want to enable CPU0 hotplug feature by default.
208180aa1dffSFenghua Yu	  You still can enable the CPU0 hotplug feature at boot by kernel
208280aa1dffSFenghua Yu	  parameter cpu0_hotplug.
208380aa1dffSFenghua Yu
2084a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0
2085a71c8bc5SFenghua Yu	def_bool n
2086a71c8bc5SFenghua Yu	prompt "Debug CPU0 hotplug"
20872c922cd0SKees Cook	depends on HOTPLUG_CPU
2088a71c8bc5SFenghua Yu	---help---
2089a71c8bc5SFenghua Yu	  Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2090a71c8bc5SFenghua Yu	  soon as possible and boots up userspace with CPU0 offlined. User
2091a71c8bc5SFenghua Yu	  can online CPU0 back after boot time.
2092a71c8bc5SFenghua Yu
2093a71c8bc5SFenghua Yu	  To debug CPU0 hotplug, you need to enable CPU0 offline/online
2094a71c8bc5SFenghua Yu	  feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2095a71c8bc5SFenghua Yu	  compilation or giving cpu0_hotplug kernel parameter at boot.
2096a71c8bc5SFenghua Yu
2097a71c8bc5SFenghua Yu	  If unsure, say N.
2098a71c8bc5SFenghua Yu
2099506f1d07SSam Ravnborgconfig COMPAT_VDSO
2100b0b49f26SAndy Lutomirski	def_bool n
2101b0b49f26SAndy Lutomirski	prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
2102953fee1dSIngo Molnar	depends on COMPAT_32
21038f9ca475SIngo Molnar	---help---
2104b0b49f26SAndy Lutomirski	  Certain buggy versions of glibc will crash if they are
2105b0b49f26SAndy Lutomirski	  presented with a 32-bit vDSO that is not mapped at the address
2106b0b49f26SAndy Lutomirski	  indicated in its segment table.
2107e84446deSRandy Dunlap
2108b0b49f26SAndy Lutomirski	  The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2109b0b49f26SAndy Lutomirski	  and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2110b0b49f26SAndy Lutomirski	  49ad572a70b8aeb91e57483a11dd1b77e31c4468.  Glibc 2.3.3 is
2111b0b49f26SAndy Lutomirski	  the only released version with the bug, but OpenSUSE 9
2112b0b49f26SAndy Lutomirski	  contains a buggy "glibc 2.3.2".
2113506f1d07SSam Ravnborg
2114b0b49f26SAndy Lutomirski	  The symptom of the bug is that everything crashes on startup, saying:
2115b0b49f26SAndy Lutomirski	  dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2116b0b49f26SAndy Lutomirski
2117b0b49f26SAndy Lutomirski	  Saying Y here changes the default value of the vdso32 boot
2118b0b49f26SAndy Lutomirski	  option from 1 to 0, which turns off the 32-bit vDSO entirely.
2119b0b49f26SAndy Lutomirski	  This works around the glibc bug but hurts performance.
2120b0b49f26SAndy Lutomirski
2121b0b49f26SAndy Lutomirski	  If unsure, say N: if you are compiling your own kernel, you
2122b0b49f26SAndy Lutomirski	  are unlikely to be using a buggy version of glibc.
2123506f1d07SSam Ravnborg
21243dc33bd3SKees Cookchoice
21253dc33bd3SKees Cook	prompt "vsyscall table for legacy applications"
21263dc33bd3SKees Cook	depends on X86_64
21273dc33bd3SKees Cook	default LEGACY_VSYSCALL_EMULATE
21283dc33bd3SKees Cook	help
21293dc33bd3SKees Cook	  Legacy user code that does not know how to find the vDSO expects
21303dc33bd3SKees Cook	  to be able to issue three syscalls by calling fixed addresses in
21313dc33bd3SKees Cook	  kernel space. Since this location is not randomized with ASLR,
21323dc33bd3SKees Cook	  it can be used to assist security vulnerability exploitation.
21333dc33bd3SKees Cook
21343dc33bd3SKees Cook	  This setting can be changed at boot time via the kernel command
21353dc33bd3SKees Cook	  line parameter vsyscall=[native|emulate|none].
21363dc33bd3SKees Cook
21373dc33bd3SKees Cook	  On a system with recent enough glibc (2.14 or newer) and no
21383dc33bd3SKees Cook	  static binaries, you can say None without a performance penalty
21393dc33bd3SKees Cook	  to improve security.
21403dc33bd3SKees Cook
21413dc33bd3SKees Cook	  If unsure, select "Emulate".
21423dc33bd3SKees Cook
21433dc33bd3SKees Cook	config LEGACY_VSYSCALL_NATIVE
21443dc33bd3SKees Cook		bool "Native"
21453dc33bd3SKees Cook		help
21463dc33bd3SKees Cook		  Actual executable code is located in the fixed vsyscall
21473dc33bd3SKees Cook		  address mapping, implementing time() efficiently. Since
21483dc33bd3SKees Cook		  this makes the mapping executable, it can be used during
21493dc33bd3SKees Cook		  security vulnerability exploitation (traditionally as
21503dc33bd3SKees Cook		  ROP gadgets). This configuration is not recommended.
21513dc33bd3SKees Cook
21523dc33bd3SKees Cook	config LEGACY_VSYSCALL_EMULATE
21533dc33bd3SKees Cook		bool "Emulate"
21543dc33bd3SKees Cook		help
21553dc33bd3SKees Cook		  The kernel traps and emulates calls into the fixed
21563dc33bd3SKees Cook		  vsyscall address mapping. This makes the mapping
21573dc33bd3SKees Cook		  non-executable, but it still contains known contents,
21583dc33bd3SKees Cook		  which could be used in certain rare security vulnerability
21593dc33bd3SKees Cook		  exploits. This configuration is recommended when userspace
21603dc33bd3SKees Cook		  still uses the vsyscall area.
21613dc33bd3SKees Cook
21623dc33bd3SKees Cook	config LEGACY_VSYSCALL_NONE
21633dc33bd3SKees Cook		bool "None"
21643dc33bd3SKees Cook		help
21653dc33bd3SKees Cook		  There will be no vsyscall mapping at all. This will
21663dc33bd3SKees Cook		  eliminate any risk of ASLR bypass due to the vsyscall
21673dc33bd3SKees Cook		  fixed address mapping. Attempts to use the vsyscalls
21683dc33bd3SKees Cook		  will be reported to dmesg, so that either old or
21693dc33bd3SKees Cook		  malicious userspace programs can be identified.
21703dc33bd3SKees Cook
21713dc33bd3SKees Cookendchoice
21723dc33bd3SKees Cook
2173516cbf37STim Birdconfig CMDLINE_BOOL
2174516cbf37STim Bird	bool "Built-in kernel command line"
21758f9ca475SIngo Molnar	---help---
2176516cbf37STim Bird	  Allow for specifying boot arguments to the kernel at
2177516cbf37STim Bird	  build time.  On some systems (e.g. embedded ones), it is
2178516cbf37STim Bird	  necessary or convenient to provide some or all of the
2179516cbf37STim Bird	  kernel boot arguments with the kernel itself (that is,
2180516cbf37STim Bird	  to not rely on the boot loader to provide them.)
2181516cbf37STim Bird
2182516cbf37STim Bird	  To compile command line arguments into the kernel,
2183516cbf37STim Bird	  set this option to 'Y', then fill in the
218469711ca1SSébastien Hinderer	  boot arguments in CONFIG_CMDLINE.
2185516cbf37STim Bird
2186516cbf37STim Bird	  Systems with fully functional boot loaders (i.e. non-embedded)
2187516cbf37STim Bird	  should leave this option set to 'N'.
2188516cbf37STim Bird
2189516cbf37STim Birdconfig CMDLINE
2190516cbf37STim Bird	string "Built-in kernel command string"
2191516cbf37STim Bird	depends on CMDLINE_BOOL
2192516cbf37STim Bird	default ""
21938f9ca475SIngo Molnar	---help---
2194516cbf37STim Bird	  Enter arguments here that should be compiled into the kernel
2195516cbf37STim Bird	  image and used at boot time.  If the boot loader provides a
2196516cbf37STim Bird	  command line at boot time, it is appended to this string to
2197516cbf37STim Bird	  form the full kernel command line, when the system boots.
2198516cbf37STim Bird
2199516cbf37STim Bird	  However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2200516cbf37STim Bird	  change this behavior.
2201516cbf37STim Bird
2202516cbf37STim Bird	  In most cases, the command line (whether built-in or provided
2203516cbf37STim Bird	  by the boot loader) should specify the device for the root
2204516cbf37STim Bird	  file system.
2205516cbf37STim Bird
2206516cbf37STim Birdconfig CMDLINE_OVERRIDE
2207516cbf37STim Bird	bool "Built-in command line overrides boot loader arguments"
2208516cbf37STim Bird	depends on CMDLINE_BOOL
22098f9ca475SIngo Molnar	---help---
2210516cbf37STim Bird	  Set this option to 'Y' to have the kernel ignore the boot loader
2211516cbf37STim Bird	  command line, and use ONLY the built-in command line.
2212516cbf37STim Bird
2213516cbf37STim Bird	  This is used to work around broken boot loaders.  This should
2214516cbf37STim Bird	  be set to 'N' under normal conditions.
2215516cbf37STim Bird
2216a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL
2217a5b9e5a2SAndy Lutomirski	bool "Enable the LDT (local descriptor table)" if EXPERT
2218a5b9e5a2SAndy Lutomirski	default y
2219a5b9e5a2SAndy Lutomirski	---help---
2220a5b9e5a2SAndy Lutomirski	  Linux can allow user programs to install a per-process x86
2221a5b9e5a2SAndy Lutomirski	  Local Descriptor Table (LDT) using the modify_ldt(2) system
2222a5b9e5a2SAndy Lutomirski	  call.  This is required to run 16-bit or segmented code such as
2223a5b9e5a2SAndy Lutomirski	  DOSEMU or some Wine programs.  It is also used by some very old
2224a5b9e5a2SAndy Lutomirski	  threading libraries.
2225a5b9e5a2SAndy Lutomirski
2226a5b9e5a2SAndy Lutomirski	  Enabling this feature adds a small amount of overhead to
2227a5b9e5a2SAndy Lutomirski	  context switches and increases the low-level kernel attack
2228a5b9e5a2SAndy Lutomirski	  surface.  Disabling it removes the modify_ldt(2) system call.
2229a5b9e5a2SAndy Lutomirski
2230a5b9e5a2SAndy Lutomirski	  Saying 'N' here may make sense for embedded or server kernels.
2231a5b9e5a2SAndy Lutomirski
2232b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig"
2233b700e7f0SSeth Jennings
2234506f1d07SSam Ravnborgendmenu
2235506f1d07SSam Ravnborg
2236506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG
2237506f1d07SSam Ravnborg	def_bool y
2238506f1d07SSam Ravnborg	depends on X86_64 || (X86_32 && HIGHMEM)
2239506f1d07SSam Ravnborg
224035551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE
224135551053SGary Hade	def_bool y
224235551053SGary Hade	depends on MEMORY_HOTPLUG
224335551053SGary Hade
2244e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID
2245645a7919STejun Heo	def_bool y
2246e534c7c5SLee Schermerhorn	depends on NUMA
2247e534c7c5SLee Schermerhorn
22489491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK
22499491846fSKirill A. Shutemov	def_bool y
22509491846fSKirill A. Shutemov	depends on X86_64 || X86_PAE
22519491846fSKirill A. Shutemov
2252c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION
2253c177c81eSNaoya Horiguchi	def_bool y
2254c177c81eSNaoya Horiguchi	depends on X86_64 && HUGETLB_PAGE && MIGRATION
2255c177c81eSNaoya Horiguchi
2256da85f865SBjorn Helgaasmenu "Power management and ACPI options"
2257e279b6c1SSam Ravnborg
2258e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER
22593c2362e6SHarvey Harrison	def_bool y
2260e279b6c1SSam Ravnborg	depends on X86_64 && HIBERNATION
2261e279b6c1SSam Ravnborg
2262e279b6c1SSam Ravnborgsource "kernel/power/Kconfig"
2263e279b6c1SSam Ravnborg
2264e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig"
2265e279b6c1SSam Ravnborg
2266efafc8b2SFeng Tangsource "drivers/sfi/Kconfig"
2267efafc8b2SFeng Tang
2268a6b68076SAndi Kleenconfig X86_APM_BOOT
22696fc108a0SJan Beulich	def_bool y
2270282e5aabSPaul Bolle	depends on APM
2271a6b68076SAndi Kleen
2272e279b6c1SSam Ravnborgmenuconfig APM
2273e279b6c1SSam Ravnborg	tristate "APM (Advanced Power Management) BIOS support"
2274efefa6f6SIngo Molnar	depends on X86_32 && PM_SLEEP
2275e279b6c1SSam Ravnborg	---help---
2276e279b6c1SSam Ravnborg	  APM is a BIOS specification for saving power using several different
2277e279b6c1SSam Ravnborg	  techniques. This is mostly useful for battery powered laptops with
2278e279b6c1SSam Ravnborg	  APM compliant BIOSes. If you say Y here, the system time will be
2279e279b6c1SSam Ravnborg	  reset after a RESUME operation, the /proc/apm device will provide
2280e279b6c1SSam Ravnborg	  battery status information, and user-space programs will receive
2281e279b6c1SSam Ravnborg	  notification of APM "events" (e.g. battery status change).
2282e279b6c1SSam Ravnborg
2283e279b6c1SSam Ravnborg	  If you select "Y" here, you can disable actual use of the APM
2284e279b6c1SSam Ravnborg	  BIOS by passing the "apm=off" option to the kernel at boot time.
2285e279b6c1SSam Ravnborg
2286e279b6c1SSam Ravnborg	  Note that the APM support is almost completely disabled for
2287e279b6c1SSam Ravnborg	  machines with more than one CPU.
2288e279b6c1SSam Ravnborg
2289e279b6c1SSam Ravnborg	  In order to use APM, you will need supporting software. For location
22902dc98fd3SMichael Witten	  and more information, read <file:Documentation/power/apm-acpi.txt>
22912dc98fd3SMichael Witten	  and the Battery Powered Linux mini-HOWTO, available from
2292e279b6c1SSam Ravnborg	  <http://www.tldp.org/docs.html#howto>.
2293e279b6c1SSam Ravnborg
2294e279b6c1SSam Ravnborg	  This driver does not spin down disk drives (see the hdparm(8)
2295e279b6c1SSam Ravnborg	  manpage ("man 8 hdparm") for that), and it doesn't turn off
2296e279b6c1SSam Ravnborg	  VESA-compliant "green" monitors.
2297e279b6c1SSam Ravnborg
2298e279b6c1SSam Ravnborg	  This driver does not support the TI 4000M TravelMate and the ACER
2299e279b6c1SSam Ravnborg	  486/DX4/75 because they don't have compliant BIOSes. Many "green"
2300e279b6c1SSam Ravnborg	  desktop machines also don't have compliant BIOSes, and this driver
2301e279b6c1SSam Ravnborg	  may cause those machines to panic during the boot phase.
2302e279b6c1SSam Ravnborg
2303e279b6c1SSam Ravnborg	  Generally, if you don't have a battery in your machine, there isn't
2304e279b6c1SSam Ravnborg	  much point in using this driver and you should say N. If you get
2305e279b6c1SSam Ravnborg	  random kernel OOPSes or reboots that don't seem to be related to
2306e279b6c1SSam Ravnborg	  anything, try disabling/enabling this option (or disabling/enabling
2307e279b6c1SSam Ravnborg	  APM in your BIOS).
2308e279b6c1SSam Ravnborg
2309e279b6c1SSam Ravnborg	  Some other things you should try when experiencing seemingly random,
2310e279b6c1SSam Ravnborg	  "weird" problems:
2311e279b6c1SSam Ravnborg
2312e279b6c1SSam Ravnborg	  1) make sure that you have enough swap space and that it is
2313e279b6c1SSam Ravnborg	  enabled.
2314e279b6c1SSam Ravnborg	  2) pass the "no-hlt" option to the kernel
2315e279b6c1SSam Ravnborg	  3) switch on floating point emulation in the kernel and pass
2316e279b6c1SSam Ravnborg	  the "no387" option to the kernel
2317e279b6c1SSam Ravnborg	  4) pass the "floppy=nodma" option to the kernel
2318e279b6c1SSam Ravnborg	  5) pass the "mem=4M" option to the kernel (thereby disabling
2319e279b6c1SSam Ravnborg	  all but the first 4 MB of RAM)
2320e279b6c1SSam Ravnborg	  6) make sure that the CPU is not over clocked.
2321e279b6c1SSam Ravnborg	  7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2322e279b6c1SSam Ravnborg	  8) disable the cache from your BIOS settings
2323e279b6c1SSam Ravnborg	  9) install a fan for the video card or exchange video RAM
2324e279b6c1SSam Ravnborg	  10) install a better fan for the CPU
2325e279b6c1SSam Ravnborg	  11) exchange RAM chips
2326e279b6c1SSam Ravnborg	  12) exchange the motherboard.
2327e279b6c1SSam Ravnborg
2328e279b6c1SSam Ravnborg	  To compile this driver as a module, choose M here: the
2329e279b6c1SSam Ravnborg	  module will be called apm.
2330e279b6c1SSam Ravnborg
2331e279b6c1SSam Ravnborgif APM
2332e279b6c1SSam Ravnborg
2333e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND
2334e279b6c1SSam Ravnborg	bool "Ignore USER SUSPEND"
23358f9ca475SIngo Molnar	---help---
2336e279b6c1SSam Ravnborg	  This option will ignore USER SUSPEND requests. On machines with a
2337e279b6c1SSam Ravnborg	  compliant APM BIOS, you want to say N. However, on the NEC Versa M
2338e279b6c1SSam Ravnborg	  series notebooks, it is necessary to say Y because of a BIOS bug.
2339e279b6c1SSam Ravnborg
2340e279b6c1SSam Ravnborgconfig APM_DO_ENABLE
2341e279b6c1SSam Ravnborg	bool "Enable PM at boot time"
2342e279b6c1SSam Ravnborg	---help---
2343e279b6c1SSam Ravnborg	  Enable APM features at boot time. From page 36 of the APM BIOS
2344e279b6c1SSam Ravnborg	  specification: "When disabled, the APM BIOS does not automatically
2345e279b6c1SSam Ravnborg	  power manage devices, enter the Standby State, enter the Suspend
2346e279b6c1SSam Ravnborg	  State, or take power saving steps in response to CPU Idle calls."
2347e279b6c1SSam Ravnborg	  This driver will make CPU Idle calls when Linux is idle (unless this
2348e279b6c1SSam Ravnborg	  feature is turned off -- see "Do CPU IDLE calls", below). This
2349e279b6c1SSam Ravnborg	  should always save battery power, but more complicated APM features
2350e279b6c1SSam Ravnborg	  will be dependent on your BIOS implementation. You may need to turn
2351e279b6c1SSam Ravnborg	  this option off if your computer hangs at boot time when using APM
2352e279b6c1SSam Ravnborg	  support, or if it beeps continuously instead of suspending. Turn
2353e279b6c1SSam Ravnborg	  this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2354e279b6c1SSam Ravnborg	  T400CDT. This is off by default since most machines do fine without
2355e279b6c1SSam Ravnborg	  this feature.
2356e279b6c1SSam Ravnborg
2357e279b6c1SSam Ravnborgconfig APM_CPU_IDLE
2358dd8af076SLen Brown	depends on CPU_IDLE
2359e279b6c1SSam Ravnborg	bool "Make CPU Idle calls when idle"
23608f9ca475SIngo Molnar	---help---
2361e279b6c1SSam Ravnborg	  Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2362e279b6c1SSam Ravnborg	  On some machines, this can activate improved power savings, such as
2363e279b6c1SSam Ravnborg	  a slowed CPU clock rate, when the machine is idle. These idle calls
2364e279b6c1SSam Ravnborg	  are made after the idle loop has run for some length of time (e.g.,
2365e279b6c1SSam Ravnborg	  333 mS). On some machines, this will cause a hang at boot time or
2366e279b6c1SSam Ravnborg	  whenever the CPU becomes idle. (On machines with more than one CPU,
2367e279b6c1SSam Ravnborg	  this option does nothing.)
2368e279b6c1SSam Ravnborg
2369e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK
2370e279b6c1SSam Ravnborg	bool "Enable console blanking using APM"
23718f9ca475SIngo Molnar	---help---
2372e279b6c1SSam Ravnborg	  Enable console blanking using the APM. Some laptops can use this to
2373e279b6c1SSam Ravnborg	  turn off the LCD backlight when the screen blanker of the Linux
2374e279b6c1SSam Ravnborg	  virtual console blanks the screen. Note that this is only used by
2375e279b6c1SSam Ravnborg	  the virtual console screen blanker, and won't turn off the backlight
2376e279b6c1SSam Ravnborg	  when using the X Window system. This also doesn't have anything to
2377e279b6c1SSam Ravnborg	  do with your VESA-compliant power-saving monitor. Further, this
2378e279b6c1SSam Ravnborg	  option doesn't work for all laptops -- it might not turn off your
2379e279b6c1SSam Ravnborg	  backlight at all, or it might print a lot of errors to the console,
2380e279b6c1SSam Ravnborg	  especially if you are using gpm.
2381e279b6c1SSam Ravnborg
2382e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS
2383e279b6c1SSam Ravnborg	bool "Allow interrupts during APM BIOS calls"
23848f9ca475SIngo Molnar	---help---
2385e279b6c1SSam Ravnborg	  Normally we disable external interrupts while we are making calls to
2386e279b6c1SSam Ravnborg	  the APM BIOS as a measure to lessen the effects of a badly behaving
2387e279b6c1SSam Ravnborg	  BIOS implementation.  The BIOS should reenable interrupts if it
2388e279b6c1SSam Ravnborg	  needs to.  Unfortunately, some BIOSes do not -- especially those in
2389e279b6c1SSam Ravnborg	  many of the newer IBM Thinkpads.  If you experience hangs when you
2390e279b6c1SSam Ravnborg	  suspend, try setting this to Y.  Otherwise, say N.
2391e279b6c1SSam Ravnborg
2392e279b6c1SSam Ravnborgendif # APM
2393e279b6c1SSam Ravnborg
2394bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig"
2395e279b6c1SSam Ravnborg
2396e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig"
2397e279b6c1SSam Ravnborg
239827471fdbSAndy Henroidsource "drivers/idle/Kconfig"
239927471fdbSAndy Henroid
2400e279b6c1SSam Ravnborgendmenu
2401e279b6c1SSam Ravnborg
2402e279b6c1SSam Ravnborg
2403e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)"
2404e279b6c1SSam Ravnborg
2405e279b6c1SSam Ravnborgconfig PCI
24061ac97018SIngo Molnar	bool "PCI support"
24071c858087SAdrian Bunk	default y
24088f9ca475SIngo Molnar	---help---
2409e279b6c1SSam Ravnborg	  Find out whether you have a PCI motherboard. PCI is the name of a
2410e279b6c1SSam Ravnborg	  bus system, i.e. the way the CPU talks to the other stuff inside
2411e279b6c1SSam Ravnborg	  your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2412e279b6c1SSam Ravnborg	  VESA. If you have PCI, say Y, otherwise N.
2413e279b6c1SSam Ravnborg
2414e279b6c1SSam Ravnborgchoice
2415e279b6c1SSam Ravnborg	prompt "PCI access mode"
2416efefa6f6SIngo Molnar	depends on X86_32 && PCI
2417e279b6c1SSam Ravnborg	default PCI_GOANY
2418e279b6c1SSam Ravnborg	---help---
2419e279b6c1SSam Ravnborg	  On PCI systems, the BIOS can be used to detect the PCI devices and
2420e279b6c1SSam Ravnborg	  determine their configuration. However, some old PCI motherboards
2421e279b6c1SSam Ravnborg	  have BIOS bugs and may crash if this is done. Also, some embedded
2422e279b6c1SSam Ravnborg	  PCI-based systems don't have any BIOS at all. Linux can also try to
2423e279b6c1SSam Ravnborg	  detect the PCI hardware directly without using the BIOS.
2424e279b6c1SSam Ravnborg
2425e279b6c1SSam Ravnborg	  With this option, you can specify how Linux should detect the
2426e279b6c1SSam Ravnborg	  PCI devices. If you choose "BIOS", the BIOS will be used,
2427e279b6c1SSam Ravnborg	  if you choose "Direct", the BIOS won't be used, and if you
2428e279b6c1SSam Ravnborg	  choose "MMConfig", then PCI Express MMCONFIG will be used.
2429e279b6c1SSam Ravnborg	  If you choose "Any", the kernel will try MMCONFIG, then the
2430e279b6c1SSam Ravnborg	  direct access method and falls back to the BIOS if that doesn't
2431e279b6c1SSam Ravnborg	  work. If unsure, go with the default, which is "Any".
2432e279b6c1SSam Ravnborg
2433e279b6c1SSam Ravnborgconfig PCI_GOBIOS
2434e279b6c1SSam Ravnborg	bool "BIOS"
2435e279b6c1SSam Ravnborg
2436e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG
2437e279b6c1SSam Ravnborg	bool "MMConfig"
2438e279b6c1SSam Ravnborg
2439e279b6c1SSam Ravnborgconfig PCI_GODIRECT
2440e279b6c1SSam Ravnborg	bool "Direct"
2441e279b6c1SSam Ravnborg
24423ef0e1f8SAndres Salomonconfig PCI_GOOLPC
244376fb6570SDaniel Drake	bool "OLPC XO-1"
24443ef0e1f8SAndres Salomon	depends on OLPC
24453ef0e1f8SAndres Salomon
24462bdd1b03SAndres Salomonconfig PCI_GOANY
24472bdd1b03SAndres Salomon	bool "Any"
24482bdd1b03SAndres Salomon
2449e279b6c1SSam Ravnborgendchoice
2450e279b6c1SSam Ravnborg
2451e279b6c1SSam Ravnborgconfig PCI_BIOS
24523c2362e6SHarvey Harrison	def_bool y
2453efefa6f6SIngo Molnar	depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2454e279b6c1SSam Ravnborg
2455e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2456e279b6c1SSam Ravnborgconfig PCI_DIRECT
24573c2362e6SHarvey Harrison	def_bool y
24580aba496fSShaohua Li	depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2459e279b6c1SSam Ravnborg
2460e279b6c1SSam Ravnborgconfig PCI_MMCONFIG
24613c2362e6SHarvey Harrison	def_bool y
24625f0db7a2SFeng Tang	depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2463e279b6c1SSam Ravnborg
24643ef0e1f8SAndres Salomonconfig PCI_OLPC
24652bdd1b03SAndres Salomon	def_bool y
24662bdd1b03SAndres Salomon	depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
24673ef0e1f8SAndres Salomon
2468b5401a96SAlex Nixonconfig PCI_XEN
2469b5401a96SAlex Nixon	def_bool y
2470b5401a96SAlex Nixon	depends on PCI && XEN
2471b5401a96SAlex Nixon	select SWIOTLB_XEN
2472b5401a96SAlex Nixon
2473e279b6c1SSam Ravnborgconfig PCI_DOMAINS
24743c2362e6SHarvey Harrison	def_bool y
2475e279b6c1SSam Ravnborg	depends on PCI
2476e279b6c1SSam Ravnborg
2477e279b6c1SSam Ravnborgconfig PCI_MMCONFIG
2478e279b6c1SSam Ravnborg	bool "Support mmconfig PCI config space access"
2479e279b6c1SSam Ravnborg	depends on X86_64 && PCI && ACPI
2480e279b6c1SSam Ravnborg
24813f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK
24826a108a14SDavid Rientjes	bool "Read CNB20LE Host Bridge Windows" if EXPERT
24836ea30386SKees Cook	depends on PCI
24843f6ea84aSIra W. Snyder	help
24853f6ea84aSIra W. Snyder	  Read the PCI windows out of the CNB20LE host bridge. This allows
24863f6ea84aSIra W. Snyder	  PCI hotplug to work on systems with the CNB20LE chipset which do
24873f6ea84aSIra W. Snyder	  not have ACPI.
24883f6ea84aSIra W. Snyder
248964a5fed6SBjorn Helgaas	  There's no public spec for this chipset, and this functionality
249064a5fed6SBjorn Helgaas	  is known to be incomplete.
249164a5fed6SBjorn Helgaas
249264a5fed6SBjorn Helgaas	  You should say N unless you know you need this.
249364a5fed6SBjorn Helgaas
2494e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig"
2495e279b6c1SSam Ravnborg
24963a495511SWilliam Breathitt Grayconfig ISA_BUS
24973a495511SWilliam Breathitt Gray	bool "ISA-style bus support on modern systems" if EXPERT
24983a495511SWilliam Breathitt Gray	select ISA_BUS_API
24993a495511SWilliam Breathitt Gray	help
25003a495511SWilliam Breathitt Gray	  Enables ISA-style drivers on modern systems. This is necessary to
25013a495511SWilliam Breathitt Gray	  support PC/104 devices on X86_64 platforms.
25023a495511SWilliam Breathitt Gray
25033a495511SWilliam Breathitt Gray	  If unsure, say N.
25043a495511SWilliam Breathitt Gray
25051c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA.
2506e279b6c1SSam Ravnborgconfig ISA_DMA_API
25071c00f016SDavid Rientjes	bool "ISA-style DMA support" if (X86_64 && EXPERT)
25081c00f016SDavid Rientjes	default y
25091c00f016SDavid Rientjes	help
25101c00f016SDavid Rientjes	  Enables ISA-style DMA support for devices requiring such controllers.
25111c00f016SDavid Rientjes	  If unsure, say Y.
2512e279b6c1SSam Ravnborg
251351e68d05SLinus Torvaldsif X86_32
251451e68d05SLinus Torvalds
2515e279b6c1SSam Ravnborgconfig ISA
2516e279b6c1SSam Ravnborg	bool "ISA support"
25178f9ca475SIngo Molnar	---help---
2518e279b6c1SSam Ravnborg	  Find out whether you have ISA slots on your motherboard.  ISA is the
2519e279b6c1SSam Ravnborg	  name of a bus system, i.e. the way the CPU talks to the other stuff
2520e279b6c1SSam Ravnborg	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
2521e279b6c1SSam Ravnborg	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2522e279b6c1SSam Ravnborg	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
2523e279b6c1SSam Ravnborg
2524e279b6c1SSam Ravnborgconfig EISA
2525e279b6c1SSam Ravnborg	bool "EISA support"
2526e279b6c1SSam Ravnborg	depends on ISA
2527e279b6c1SSam Ravnborg	---help---
2528e279b6c1SSam Ravnborg	  The Extended Industry Standard Architecture (EISA) bus was
2529e279b6c1SSam Ravnborg	  developed as an open alternative to the IBM MicroChannel bus.
2530e279b6c1SSam Ravnborg
2531e279b6c1SSam Ravnborg	  The EISA bus provided some of the features of the IBM MicroChannel
2532e279b6c1SSam Ravnborg	  bus while maintaining backward compatibility with cards made for
2533e279b6c1SSam Ravnborg	  the older ISA bus.  The EISA bus saw limited use between 1988 and
2534e279b6c1SSam Ravnborg	  1995 when it was made obsolete by the PCI bus.
2535e279b6c1SSam Ravnborg
2536e279b6c1SSam Ravnborg	  Say Y here if you are building a kernel for an EISA-based machine.
2537e279b6c1SSam Ravnborg
2538e279b6c1SSam Ravnborg	  Otherwise, say N.
2539e279b6c1SSam Ravnborg
2540e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig"
2541e279b6c1SSam Ravnborg
2542e279b6c1SSam Ravnborgconfig SCx200
2543e279b6c1SSam Ravnborg	tristate "NatSemi SCx200 support"
25448f9ca475SIngo Molnar	---help---
2545e279b6c1SSam Ravnborg	  This provides basic support for National Semiconductor's
2546e279b6c1SSam Ravnborg	  (now AMD's) Geode processors.  The driver probes for the
2547e279b6c1SSam Ravnborg	  PCI-IDs of several on-chip devices, so its a good dependency
2548e279b6c1SSam Ravnborg	  for other scx200_* drivers.
2549e279b6c1SSam Ravnborg
2550e279b6c1SSam Ravnborg	  If compiled as a module, the driver is named scx200.
2551e279b6c1SSam Ravnborg
2552e279b6c1SSam Ravnborgconfig SCx200HR_TIMER
2553e279b6c1SSam Ravnborg	tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2554592913ecSJohn Stultz	depends on SCx200
2555e279b6c1SSam Ravnborg	default y
25568f9ca475SIngo Molnar	---help---
2557e279b6c1SSam Ravnborg	  This driver provides a clocksource built upon the on-chip
2558e279b6c1SSam Ravnborg	  27MHz high-resolution timer.  Its also a workaround for
2559e279b6c1SSam Ravnborg	  NSC Geode SC-1100's buggy TSC, which loses time when the
2560e279b6c1SSam Ravnborg	  processor goes idle (as is done by the scheduler).  The
2561e279b6c1SSam Ravnborg	  other workaround is idle=poll boot option.
2562e279b6c1SSam Ravnborg
25633ef0e1f8SAndres Salomonconfig OLPC
25643ef0e1f8SAndres Salomon	bool "One Laptop Per Child support"
256554008979SThomas Gleixner	depends on !X86_PAE
25663c554946SAndres Salomon	select GPIOLIB
2567dc3119e7SThomas Gleixner	select OF
256845bb1674SDaniel Drake	select OF_PROMTREE
2569b4e51854SGrant Likely	select IRQ_DOMAIN
25708f9ca475SIngo Molnar	---help---
25713ef0e1f8SAndres Salomon	  Add support for detecting the unique features of the OLPC
25723ef0e1f8SAndres Salomon	  XO hardware.
25733ef0e1f8SAndres Salomon
2574a3128588SDaniel Drakeconfig OLPC_XO1_PM
2575a3128588SDaniel Drake	bool "OLPC XO-1 Power Management"
257697c4cb71SDaniel Drake	depends on OLPC && MFD_CS5535 && PM_SLEEP
2577a3128588SDaniel Drake	select MFD_CORE
2578bf1ebf00SDaniel Drake	---help---
257997c4cb71SDaniel Drake	  Add support for poweroff and suspend of the OLPC XO-1 laptop.
2580bf1ebf00SDaniel Drake
2581cfee9597SDaniel Drakeconfig OLPC_XO1_RTC
2582cfee9597SDaniel Drake	bool "OLPC XO-1 Real Time Clock"
2583cfee9597SDaniel Drake	depends on OLPC_XO1_PM && RTC_DRV_CMOS
2584cfee9597SDaniel Drake	---help---
2585cfee9597SDaniel Drake	  Add support for the XO-1 real time clock, which can be used as a
2586cfee9597SDaniel Drake	  programmable wakeup source.
2587cfee9597SDaniel Drake
25887feda8e9SDaniel Drakeconfig OLPC_XO1_SCI
25897feda8e9SDaniel Drake	bool "OLPC XO-1 SCI extras"
2590d8d01a63SDaniel Drake	depends on OLPC && OLPC_XO1_PM
2591ed8e47feSRandy Dunlap	depends on INPUT=y
2592d8d01a63SDaniel Drake	select POWER_SUPPLY
25937feda8e9SDaniel Drake	select GPIO_CS5535
25947feda8e9SDaniel Drake	select MFD_CORE
25957feda8e9SDaniel Drake	---help---
25967feda8e9SDaniel Drake	  Add support for SCI-based features of the OLPC XO-1 laptop:
25977bc74b3dSDaniel Drake	   - EC-driven system wakeups
25987feda8e9SDaniel Drake	   - Power button
25997bc74b3dSDaniel Drake	   - Ebook switch
26002cf2baeaSDaniel Drake	   - Lid switch
2601e1040ac6SDaniel Drake	   - AC adapter status updates
2602e1040ac6SDaniel Drake	   - Battery status updates
26037feda8e9SDaniel Drake
2604a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI
2605a0f30f59SDaniel Drake	bool "OLPC XO-1.5 SCI extras"
2606d8d01a63SDaniel Drake	depends on OLPC && ACPI
2607d8d01a63SDaniel Drake	select POWER_SUPPLY
2608a0f30f59SDaniel Drake	---help---
2609a0f30f59SDaniel Drake	  Add support for SCI-based features of the OLPC XO-1.5 laptop:
2610a0f30f59SDaniel Drake	   - EC-driven system wakeups
2611a0f30f59SDaniel Drake	   - AC adapter status updates
2612a0f30f59SDaniel Drake	   - Battery status updates
2613e279b6c1SSam Ravnborg
2614d4f3e350SEd Wildgooseconfig ALIX
2615d4f3e350SEd Wildgoose	bool "PCEngines ALIX System Support (LED setup)"
2616d4f3e350SEd Wildgoose	select GPIOLIB
2617d4f3e350SEd Wildgoose	---help---
2618d4f3e350SEd Wildgoose	  This option enables system support for the PCEngines ALIX.
2619d4f3e350SEd Wildgoose	  At present this just sets up LEDs for GPIO control on
2620d4f3e350SEd Wildgoose	  ALIX2/3/6 boards.  However, other system specific setup should
2621d4f3e350SEd Wildgoose	  get added here.
2622d4f3e350SEd Wildgoose
2623d4f3e350SEd Wildgoose	  Note: You must still enable the drivers for GPIO and LED support
2624d4f3e350SEd Wildgoose	  (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2625d4f3e350SEd Wildgoose
2626d4f3e350SEd Wildgoose	  Note: You have to set alix.force=1 for boards with Award BIOS.
2627d4f3e350SEd Wildgoose
2628da4e3302SPhilip Prindevilleconfig NET5501
2629da4e3302SPhilip Prindeville	bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2630da4e3302SPhilip Prindeville	select GPIOLIB
2631da4e3302SPhilip Prindeville	---help---
2632da4e3302SPhilip Prindeville	  This option enables system support for the Soekris Engineering net5501.
2633da4e3302SPhilip Prindeville
26343197059aSPhilip A. Prindevilleconfig GEOS
26353197059aSPhilip A. Prindeville	bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
26363197059aSPhilip A. Prindeville	select GPIOLIB
26373197059aSPhilip A. Prindeville	depends on DMI
26383197059aSPhilip A. Prindeville	---help---
26393197059aSPhilip A. Prindeville	  This option enables system support for the Traverse Technologies GEOS.
26403197059aSPhilip A. Prindeville
26417d029125SVivien Didelotconfig TS5500
26427d029125SVivien Didelot	bool "Technologic Systems TS-5500 platform support"
26437d029125SVivien Didelot	depends on MELAN
26447d029125SVivien Didelot	select CHECK_SIGNATURE
26457d029125SVivien Didelot	select NEW_LEDS
26467d029125SVivien Didelot	select LEDS_CLASS
26477d029125SVivien Didelot	---help---
26487d029125SVivien Didelot	  This option enables system support for the Technologic Systems TS-5500.
26497d029125SVivien Didelot
2650e279b6c1SSam Ravnborgendif # X86_32
2651e279b6c1SSam Ravnborg
265223ac4ae8SAndreas Herrmannconfig AMD_NB
2653e279b6c1SSam Ravnborg	def_bool y
26540e152cd7SBorislav Petkov	depends on CPU_SUP_AMD && PCI
2655e279b6c1SSam Ravnborg
2656e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig"
2657e279b6c1SSam Ravnborg
2658388b78adSAlexandre Bounineconfig RAPIDIO
2659fdf90abcSAlexandre Bounine	tristate "RapidIO support"
2660388b78adSAlexandre Bounine	depends on PCI
2661388b78adSAlexandre Bounine	default n
2662388b78adSAlexandre Bounine	help
2663fdf90abcSAlexandre Bounine	  If enabled this option will include drivers and the core
2664388b78adSAlexandre Bounine	  infrastructure code to support RapidIO interconnect devices.
2665388b78adSAlexandre Bounine
2666388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig"
2667388b78adSAlexandre Bounine
2668e3263ab3SDavid Herrmannconfig X86_SYSFB
2669e3263ab3SDavid Herrmann	bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2670e3263ab3SDavid Herrmann	help
2671e3263ab3SDavid Herrmann	  Firmwares often provide initial graphics framebuffers so the BIOS,
2672e3263ab3SDavid Herrmann	  bootloader or kernel can show basic video-output during boot for
2673e3263ab3SDavid Herrmann	  user-guidance and debugging. Historically, x86 used the VESA BIOS
2674e3263ab3SDavid Herrmann	  Extensions and EFI-framebuffers for this, which are mostly limited
2675e3263ab3SDavid Herrmann	  to x86.
2676e3263ab3SDavid Herrmann	  This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2677e3263ab3SDavid Herrmann	  framebuffers so the new generic system-framebuffer drivers can be
2678e3263ab3SDavid Herrmann	  used on x86. If the framebuffer is not compatible with the generic
2679e3263ab3SDavid Herrmann	  modes, it is adverticed as fallback platform framebuffer so legacy
2680e3263ab3SDavid Herrmann	  drivers like efifb, vesafb and uvesafb can pick it up.
2681e3263ab3SDavid Herrmann	  If this option is not selected, all system framebuffers are always
2682e3263ab3SDavid Herrmann	  marked as fallback platform framebuffers as usual.
2683e3263ab3SDavid Herrmann
2684e3263ab3SDavid Herrmann	  Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2685e3263ab3SDavid Herrmann	  not be able to pick up generic system framebuffers if this option
2686e3263ab3SDavid Herrmann	  is selected. You are highly encouraged to enable simplefb as
2687e3263ab3SDavid Herrmann	  replacement if you select this option. simplefb can correctly deal
2688e3263ab3SDavid Herrmann	  with generic system framebuffers. But you should still keep vesafb
2689e3263ab3SDavid Herrmann	  and others enabled as fallback if a system framebuffer is
2690e3263ab3SDavid Herrmann	  incompatible with simplefb.
2691e3263ab3SDavid Herrmann
2692e3263ab3SDavid Herrmann	  If unsure, say Y.
2693e3263ab3SDavid Herrmann
2694e279b6c1SSam Ravnborgendmenu
2695e279b6c1SSam Ravnborg
2696e279b6c1SSam Ravnborg
2697e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations"
2698e279b6c1SSam Ravnborg
2699e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt"
2700e279b6c1SSam Ravnborg
2701e279b6c1SSam Ravnborgconfig IA32_EMULATION
2702e279b6c1SSam Ravnborg	bool "IA32 Emulation"
2703e279b6c1SSam Ravnborg	depends on X86_64
270439f88911SIngo Molnar	select ARCH_WANT_OLD_COMPAT_IPC
2705d1603990SRandy Dunlap	select BINFMT_ELF
2706a97f52e6SRoland McGrath	select COMPAT_BINFMT_ELF
270739f88911SIngo Molnar	select COMPAT_OLD_SIGACTION
27088f9ca475SIngo Molnar	---help---
27095fd92e65SH. J. Lu	  Include code to run legacy 32-bit programs under a
27105fd92e65SH. J. Lu	  64-bit kernel. You should likely turn this on, unless you're
27115fd92e65SH. J. Lu	  100% sure that you don't have any 32-bit programs left.
2712e279b6c1SSam Ravnborg
2713e279b6c1SSam Ravnborgconfig IA32_AOUT
2714e279b6c1SSam Ravnborg	tristate "IA32 a.out support"
27156b213e1bSDavid Woodhouse	depends on IA32_EMULATION
27168f9ca475SIngo Molnar	---help---
2717e279b6c1SSam Ravnborg	  Support old a.out binaries in the 32bit emulation.
2718e279b6c1SSam Ravnborg
27190bf62763SH. Peter Anvinconfig X86_X32
27206ea30386SKees Cook	bool "x32 ABI for 64-bit mode"
27219b54050bSBrian Gerst	depends on X86_64
27225fd92e65SH. J. Lu	---help---
27235fd92e65SH. J. Lu	  Include code to run binaries for the x32 native 32-bit ABI
27245fd92e65SH. J. Lu	  for 64-bit processors.  An x32 process gets access to the
27255fd92e65SH. J. Lu	  full 64-bit register file and wide data path while leaving
27265fd92e65SH. J. Lu	  pointers at 32 bits for smaller memory footprint.
27275fd92e65SH. J. Lu
27285fd92e65SH. J. Lu	  You will need a recent binutils (2.22 or later) with
27295fd92e65SH. J. Lu	  elf32_x86_64 support enabled to compile a kernel with this
27305fd92e65SH. J. Lu	  option set.
27315fd92e65SH. J. Lu
2732953fee1dSIngo Molnarconfig COMPAT_32
2733953fee1dSIngo Molnar	def_bool y
2734953fee1dSIngo Molnar	depends on IA32_EMULATION || X86_32
2735953fee1dSIngo Molnar	select HAVE_UID16
2736953fee1dSIngo Molnar	select OLD_SIGSUSPEND3
2737953fee1dSIngo Molnar
2738e279b6c1SSam Ravnborgconfig COMPAT
27393c2362e6SHarvey Harrison	def_bool y
27400bf62763SH. Peter Anvin	depends on IA32_EMULATION || X86_X32
2741e279b6c1SSam Ravnborg
27423120e25eSJan Beulichif COMPAT
2743e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT
27443120e25eSJan Beulich	def_bool y
2745e279b6c1SSam Ravnborg
2746e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT
27473c2362e6SHarvey Harrison	def_bool y
27483120e25eSJan Beulich	depends on SYSVIPC
2749e279b6c1SSam Ravnborg
2750ee009e4aSDavid Howellsconfig KEYS_COMPAT
27513120e25eSJan Beulich	def_bool y
27523120e25eSJan Beulich	depends on KEYS
27533120e25eSJan Beulichendif
2754ee009e4aSDavid Howells
2755e279b6c1SSam Ravnborgendmenu
2756e279b6c1SSam Ravnborg
2757e279b6c1SSam Ravnborg
2758e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP
2759e5beae16SKeith Packard	def_bool y
2760e5beae16SKeith Packard	depends on X86_32
2761e5beae16SKeith Packard
27624692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS
27634692d77fSAlessandro Rubini	bool
276483125a3aSAlessandro Rubini	depends on X86_64 || STA2X11
27654692d77fSAlessandro Rubini
2766f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP
2767f7219a53SAlessandro Rubini	bool
276883125a3aSAlessandro Rubini	depends on STA2X11
2769f7219a53SAlessandro Rubini
277093e5eaddSLi, Aubreyconfig PMC_ATOM
277193e5eaddSLi, Aubrey	def_bool y
277293e5eaddSLi, Aubrey        depends on PCI
277393e5eaddSLi, Aubrey
2774e279b6c1SSam Ravnborgsource "net/Kconfig"
2775e279b6c1SSam Ravnborg
2776e279b6c1SSam Ravnborgsource "drivers/Kconfig"
2777e279b6c1SSam Ravnborg
2778e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig"
2779e279b6c1SSam Ravnborg
2780e279b6c1SSam Ravnborgsource "fs/Kconfig"
2781e279b6c1SSam Ravnborg
2782e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug"
2783e279b6c1SSam Ravnborg
2784e279b6c1SSam Ravnborgsource "security/Kconfig"
2785e279b6c1SSam Ravnborg
2786e279b6c1SSam Ravnborgsource "crypto/Kconfig"
2787e279b6c1SSam Ravnborg
2788edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig"
2789edf88417SAvi Kivity
2790e279b6c1SSam Ravnborgsource "lib/Kconfig"
2791