xref: /linux/arch/x86/Kconfig (revision 76b043848fd22dbf7f8bf3a1452f8c70d557b860)
1b2441318SGreg Kroah-Hartman# SPDX-License-Identifier: GPL-2.0
2daa93fabSSam Ravnborg# Select 32 or 64 bit
3daa93fabSSam Ravnborgconfig 64BIT
46840999bSSam Ravnborg	bool "64-bit kernel" if ARCH = "x86"
5ffee0de4SDavid Woodhouse	default ARCH != "i386"
68f9ca475SIngo Molnar	---help---
7daa93fabSSam Ravnborg	  Say yes to build a 64-bit kernel - formerly known as x86_64
8daa93fabSSam Ravnborg	  Say no to build a 32-bit kernel - formerly known as i386
9daa93fabSSam Ravnborg
10daa93fabSSam Ravnborgconfig X86_32
113120e25eSJan Beulich	def_bool y
123120e25eSJan Beulich	depends on !64BIT
13341c787eSIngo Molnar	# Options that are inherently 32-bit kernel only:
14341c787eSIngo Molnar	select ARCH_WANT_IPC_PARSE_VERSION
15341c787eSIngo Molnar	select CLKSRC_I8253
16341c787eSIngo Molnar	select CLONE_BACKWARDS
17341c787eSIngo Molnar	select HAVE_AOUT
18341c787eSIngo Molnar	select HAVE_GENERIC_DMA_COHERENT
19341c787eSIngo Molnar	select MODULES_USE_ELF_REL
20341c787eSIngo Molnar	select OLD_SIGACTION
21daa93fabSSam Ravnborg
22daa93fabSSam Ravnborgconfig X86_64
233120e25eSJan Beulich	def_bool y
243120e25eSJan Beulich	depends on 64BIT
25d94e0685SIngo Molnar	# Options that are inherently 64-bit kernel only:
26e1073d1eSAneesh Kumar K.V	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
27d94e0685SIngo Molnar	select ARCH_SUPPORTS_INT128
28d94e0685SIngo Molnar	select ARCH_USE_CMPXCHG_LOCKREF
29d94e0685SIngo Molnar	select HAVE_ARCH_SOFT_DIRTY
30d94e0685SIngo Molnar	select MODULES_USE_ELF_RELA
31d94e0685SIngo Molnar	select X86_DEV_DMA_OPS
321032c0baSSam Ravnborg
33d94e0685SIngo Molnar#
34d94e0685SIngo Molnar# Arch settings
35d94e0685SIngo Molnar#
36d94e0685SIngo Molnar# ( Note that options that are marked 'if X86_64' could in principle be
37d94e0685SIngo Molnar#   ported to 32-bit as well. )
38d94e0685SIngo Molnar#
398d5fffb9SSam Ravnborgconfig X86
403c2362e6SHarvey Harrison	def_bool y
41c763ea26SIngo Molnar	#
42c763ea26SIngo Molnar	# Note: keep this list sorted alphabetically
43c763ea26SIngo Molnar	#
446471b825SIngo Molnar	select ACPI_LEGACY_TABLES_LOOKUP	if ACPI
456e0a0ea1SGraeme Gregory	select ACPI_SYSTEM_POWER_STATES_SUPPORT	if ACPI
466471b825SIngo Molnar	select ANON_INODES
476471b825SIngo Molnar	select ARCH_CLOCKSOURCE_DATA
486471b825SIngo Molnar	select ARCH_DISCARD_MEMBLOCK
4991dda51aSAleksey Makarov	select ARCH_HAS_ACPI_TABLE_UPGRADE	if ACPI
50fa5b6ec9SLaura Abbott	select ARCH_HAS_DEBUG_VIRTUAL
5121266be9SDan Williams	select ARCH_HAS_DEVMEM_IS_ALLOWED
526471b825SIngo Molnar	select ARCH_HAS_ELF_RANDOMIZE
5372d93104SLinus Torvalds	select ARCH_HAS_FAST_MULTIPLIER
546974f0c4SDaniel Micay	select ARCH_HAS_FORTIFY_SOURCE
55957e3facSRiku Voipio	select ARCH_HAS_GCOV_PROFILE_ALL
565c9a8750SDmitry Vyukov	select ARCH_HAS_KCOV			if X86_64
57c763ea26SIngo Molnar	select ARCH_HAS_PMEM_API		if X86_64
587b3d61ccSIngo Molnar	# Causing hangs/crashes, see the commit that added this change for details.
597b3d61ccSIngo Molnar	select ARCH_HAS_REFCOUNT		if BROKEN
600aed55afSDan Williams	select ARCH_HAS_UACCESS_FLUSHCACHE	if X86_64
61d2852a22SDaniel Borkmann	select ARCH_HAS_SET_MEMORY
626471b825SIngo Molnar	select ARCH_HAS_SG_CHAIN
63ad21fc4fSLaura Abbott	select ARCH_HAS_STRICT_KERNEL_RWX
64ad21fc4fSLaura Abbott	select ARCH_HAS_STRICT_MODULE_RWX
65c6d30853SAndrey Ryabinin	select ARCH_HAS_UBSAN_SANITIZE_ALL
6665f7d049SOliver O'Halloran	select ARCH_HAS_ZONE_DEVICE		if X86_64
676471b825SIngo Molnar	select ARCH_HAVE_NMI_SAFE_CMPXCHG
686471b825SIngo Molnar	select ARCH_MIGHT_HAVE_ACPI_PDC		if ACPI
6977fbbc81SMark Salter	select ARCH_MIGHT_HAVE_PC_PARPORT
705e2c18c0SMark Salter	select ARCH_MIGHT_HAVE_PC_SERIO
716471b825SIngo Molnar	select ARCH_SUPPORTS_ATOMIC_RMW
723b242c66SMel Gorman	select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
736471b825SIngo Molnar	select ARCH_SUPPORTS_NUMA_BALANCING	if X86_64
746471b825SIngo Molnar	select ARCH_USE_BUILTIN_BSWAP
756471b825SIngo Molnar	select ARCH_USE_QUEUED_RWLOCKS
766471b825SIngo Molnar	select ARCH_USE_QUEUED_SPINLOCKS
77ce4a4e56SAndy Lutomirski	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
78c763ea26SIngo Molnar	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
7938d8b4e6SHuang Ying	select ARCH_WANTS_THP_SWAP		if X86_64
806471b825SIngo Molnar	select BUILDTIME_EXTABLE_SORT
816471b825SIngo Molnar	select CLKEVT_I8253
826471b825SIngo Molnar	select CLOCKSOURCE_VALIDATE_LAST_CYCLE
836471b825SIngo Molnar	select CLOCKSOURCE_WATCHDOG
846471b825SIngo Molnar	select DCACHE_WORD_ACCESS
8545471cd9SLinus Torvalds	select EDAC_ATOMIC_SCRUB
8645471cd9SLinus Torvalds	select EDAC_SUPPORT
876471b825SIngo Molnar	select GENERIC_CLOCKEVENTS
886471b825SIngo Molnar	select GENERIC_CLOCKEVENTS_BROADCAST	if X86_64 || (X86_32 && X86_LOCAL_APIC)
896471b825SIngo Molnar	select GENERIC_CLOCKEVENTS_MIN_ADJUST
906471b825SIngo Molnar	select GENERIC_CMOS_UPDATE
916471b825SIngo Molnar	select GENERIC_CPU_AUTOPROBE
9261dc0f55SThomas Gleixner	select GENERIC_CPU_VULNERABILITIES
936471b825SIngo Molnar	select GENERIC_EARLY_IOREMAP
946471b825SIngo Molnar	select GENERIC_FIND_FIRST_BIT
956471b825SIngo Molnar	select GENERIC_IOMAP
96c7d6c9ddSThomas Gleixner	select GENERIC_IRQ_EFFECTIVE_AFF_MASK	if SMP
97ad7a929fSThomas Gleixner	select GENERIC_IRQ_MIGRATION		if SMP
986471b825SIngo Molnar	select GENERIC_IRQ_PROBE
996471b825SIngo Molnar	select GENERIC_IRQ_SHOW
1006471b825SIngo Molnar	select GENERIC_PENDING_IRQ		if SMP
1016471b825SIngo Molnar	select GENERIC_SMP_IDLE_THREAD
1026471b825SIngo Molnar	select GENERIC_STRNCPY_FROM_USER
1036471b825SIngo Molnar	select GENERIC_STRNLEN_USER
1046471b825SIngo Molnar	select GENERIC_TIME_VSYSCALL
1057edaeb68SThomas Gleixner	select HARDLOCKUP_CHECK_TIMESTAMP	if X86_64
1066471b825SIngo Molnar	select HAVE_ACPI_APEI			if ACPI
1076471b825SIngo Molnar	select HAVE_ACPI_APEI_NMI		if ACPI
1086471b825SIngo Molnar	select HAVE_ALIGNED_STRUCT_PAGE		if SLUB
1096471b825SIngo Molnar	select HAVE_ARCH_AUDITSYSCALL
1106471b825SIngo Molnar	select HAVE_ARCH_HUGE_VMAP		if X86_64 || X86_PAE
1116471b825SIngo Molnar	select HAVE_ARCH_JUMP_LABEL
1122aeb0736SAndrey Ryabinin	select HAVE_ARCH_KASAN			if X86_64
1136471b825SIngo Molnar	select HAVE_ARCH_KGDB
1146471b825SIngo Molnar	select HAVE_ARCH_KMEMCHECK
1159e08f57dSDaniel Cashman	select HAVE_ARCH_MMAP_RND_BITS		if MMU
1169e08f57dSDaniel Cashman	select HAVE_ARCH_MMAP_RND_COMPAT_BITS	if MMU && COMPAT
1171b028f78SDmitry Safonov	select HAVE_ARCH_COMPAT_MMAP_BASES	if MMU && COMPAT
1186471b825SIngo Molnar	select HAVE_ARCH_SECCOMP_FILTER
1196471b825SIngo Molnar	select HAVE_ARCH_TRACEHOOK
1206471b825SIngo Molnar	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
121a00cc7d9SMatthew Wilcox	select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
122e37e43a4SAndy Lutomirski	select HAVE_ARCH_VMAP_STACK		if X86_64
123c763ea26SIngo Molnar	select HAVE_ARCH_WITHIN_STACK_FRAMES
1246471b825SIngo Molnar	select HAVE_CC_STACKPROTECTOR
1256471b825SIngo Molnar	select HAVE_CMPXCHG_DOUBLE
1266471b825SIngo Molnar	select HAVE_CMPXCHG_LOCAL
1276471b825SIngo Molnar	select HAVE_CONTEXT_TRACKING		if X86_64
128c1bd55f9SJosh Triplett	select HAVE_COPY_THREAD_TLS
1296471b825SIngo Molnar	select HAVE_C_RECORDMCOUNT
1306471b825SIngo Molnar	select HAVE_DEBUG_KMEMLEAK
1316471b825SIngo Molnar	select HAVE_DEBUG_STACKOVERFLOW
1326471b825SIngo Molnar	select HAVE_DMA_API_DEBUG
1339c5a3621SAkinobu Mita	select HAVE_DMA_CONTIGUOUS
134677aa9f7SSteven Rostedt	select HAVE_DYNAMIC_FTRACE
13506aeaaeaSMasami Hiramatsu	select HAVE_DYNAMIC_FTRACE_WITH_REGS
136c763ea26SIngo Molnar	select HAVE_EBPF_JIT			if X86_64
13758340a07SJohannes Berg	select HAVE_EFFICIENT_UNALIGNED_ACCESS
1385f56a5dfSJiri Slaby	select HAVE_EXIT_THREAD
139644e0e8dSSteven Rostedt (VMware)	select HAVE_FENTRY			if X86_64 || DYNAMIC_FTRACE
1406471b825SIngo Molnar	select HAVE_FTRACE_MCOUNT_RECORD
1416471b825SIngo Molnar	select HAVE_FUNCTION_GRAPH_TRACER
1426471b825SIngo Molnar	select HAVE_FUNCTION_TRACER
1436b90bd4bSEmese Revfy	select HAVE_GCC_PLUGINS
1440067f129SK.Prasad	select HAVE_HW_BREAKPOINT
1456471b825SIngo Molnar	select HAVE_IDE
1466471b825SIngo Molnar	select HAVE_IOREMAP_PROT
1476471b825SIngo Molnar	select HAVE_IRQ_EXIT_ON_IRQ_STACK	if X86_64
1486471b825SIngo Molnar	select HAVE_IRQ_TIME_ACCOUNTING
1496471b825SIngo Molnar	select HAVE_KERNEL_BZIP2
1506471b825SIngo Molnar	select HAVE_KERNEL_GZIP
1516471b825SIngo Molnar	select HAVE_KERNEL_LZ4
1526471b825SIngo Molnar	select HAVE_KERNEL_LZMA
1536471b825SIngo Molnar	select HAVE_KERNEL_LZO
1546471b825SIngo Molnar	select HAVE_KERNEL_XZ
1556471b825SIngo Molnar	select HAVE_KPROBES
1566471b825SIngo Molnar	select HAVE_KPROBES_ON_FTRACE
1576471b825SIngo Molnar	select HAVE_KRETPROBES
1586471b825SIngo Molnar	select HAVE_KVM
1596471b825SIngo Molnar	select HAVE_LIVEPATCH			if X86_64
1606471b825SIngo Molnar	select HAVE_MEMBLOCK
1616471b825SIngo Molnar	select HAVE_MEMBLOCK_NODE_MAP
1620102752eSFrederic Weisbecker	select HAVE_MIXED_BREAKPOINTS_REGS
163ee9f8fceSJosh Poimboeuf	select HAVE_MOD_ARCH_SPECIFIC
16442a0bb3fSPetr Mladek	select HAVE_NMI
1656471b825SIngo Molnar	select HAVE_OPROFILE
1666471b825SIngo Molnar	select HAVE_OPTPROBES
1676471b825SIngo Molnar	select HAVE_PCSPKR_PLATFORM
1686471b825SIngo Molnar	select HAVE_PERF_EVENTS
169c01d4323SFrederic Weisbecker	select HAVE_PERF_EVENTS_NMI
17092e5aae4SNicholas Piggin	select HAVE_HARDLOCKUP_DETECTOR_PERF	if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
171c5e63197SJiri Olsa	select HAVE_PERF_REGS
172c5ebcedbSJiri Olsa	select HAVE_PERF_USER_STACK_DUMP
1739e52fc2bSVitaly Kuznetsov	select HAVE_RCU_TABLE_FREE
1746471b825SIngo Molnar	select HAVE_REGS_AND_STACK_ACCESS_API
17511af8474SJosh Poimboeuf	select HAVE_RELIABLE_STACKTRACE		if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
176c763ea26SIngo Molnar	select HAVE_STACK_VALIDATION		if X86_64
1776471b825SIngo Molnar	select HAVE_SYSCALL_TRACEPOINTS
1786471b825SIngo Molnar	select HAVE_UNSTABLE_SCHED_CLOCK
1797c68af6eSAvi Kivity	select HAVE_USER_RETURN_NOTIFIER
180c0185808SThomas Gleixner	select IRQ_FORCED_THREADING
181df65c1bcSThomas Gleixner	select PCI_LOCKLESS_CONFIG
1826471b825SIngo Molnar	select PERF_EVENTS
1833195ef59SPrarit Bhargava	select RTC_LIB
184d6faca40SArnd Bergmann	select RTC_MC146818_LIB
1856471b825SIngo Molnar	select SPARSE_IRQ
18683fe27eaSPranith Kumar	select SRCU
1876471b825SIngo Molnar	select SYSCTL_EXCEPTION_TRACE
18815f4eae7SAndy Lutomirski	select THREAD_INFO_IN_TASK
1896471b825SIngo Molnar	select USER_STACKTRACE_SUPPORT
1906471b825SIngo Molnar	select VIRT_TO_BUS
1916471b825SIngo Molnar	select X86_FEATURE_NAMES		if PROC_FS
1927d8330a5SBalbir Singh
193ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER
1943120e25eSJan Beulich	def_bool y
1953120e25eSJan Beulich	depends on KPROBES || PERF_EVENTS || UPROBES
196ba7e4d13SIngo Molnar
19751b26adaSLinus Torvaldsconfig OUTPUT_FORMAT
19851b26adaSLinus Torvalds	string
19951b26adaSLinus Torvalds	default "elf32-i386" if X86_32
20051b26adaSLinus Torvalds	default "elf64-x86-64" if X86_64
20151b26adaSLinus Torvalds
20273531905SSam Ravnborgconfig ARCH_DEFCONFIG
203b9b39bfbSSam Ravnborg	string
20473531905SSam Ravnborg	default "arch/x86/configs/i386_defconfig" if X86_32
20573531905SSam Ravnborg	default "arch/x86/configs/x86_64_defconfig" if X86_64
206b9b39bfbSSam Ravnborg
2078d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT
2083c2362e6SHarvey Harrison	def_bool y
2098d5fffb9SSam Ravnborg
2108d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT
2113c2362e6SHarvey Harrison	def_bool y
2128d5fffb9SSam Ravnborg
2138d5fffb9SSam Ravnborgconfig MMU
2143c2362e6SHarvey Harrison	def_bool y
2158d5fffb9SSam Ravnborg
2169e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN
2179e08f57dSDaniel Cashman	default 28 if 64BIT
2189e08f57dSDaniel Cashman	default 8
2199e08f57dSDaniel Cashman
2209e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX
2219e08f57dSDaniel Cashman	default 32 if 64BIT
2229e08f57dSDaniel Cashman	default 16
2239e08f57dSDaniel Cashman
2249e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN
2259e08f57dSDaniel Cashman	default 8
2269e08f57dSDaniel Cashman
2279e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX
2289e08f57dSDaniel Cashman	default 16
2299e08f57dSDaniel Cashman
2308d5fffb9SSam Ravnborgconfig SBUS
2318d5fffb9SSam Ravnborg	bool
2328d5fffb9SSam Ravnborg
2333bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE
2343120e25eSJan Beulich	def_bool y
235a6dfa128SKonrad Rzeszutek Wilk	depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
2363bc4e459SFUJITA Tomonori
23718e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH
2384a14d84eSAndrew Morton	def_bool y
23918e98307SFUJITA Tomonori
2408d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA
2413120e25eSJan Beulich	def_bool y
2423120e25eSJan Beulich	depends on ISA_DMA_API
2438d5fffb9SSam Ravnborg
2448d5fffb9SSam Ravnborgconfig GENERIC_BUG
2453c2362e6SHarvey Harrison	def_bool y
2468d5fffb9SSam Ravnborg	depends on BUG
247b93a531eSJan Beulich	select GENERIC_BUG_RELATIVE_POINTERS if X86_64
248b93a531eSJan Beulich
249b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS
250b93a531eSJan Beulich	bool
2518d5fffb9SSam Ravnborg
2528d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT
2533c2362e6SHarvey Harrison	def_bool y
2548d5fffb9SSam Ravnborg
2558d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC
2563120e25eSJan Beulich	def_bool y
2573120e25eSJan Beulich	depends on ISA_DMA_API
2588d5fffb9SSam Ravnborg
2591032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM
2603120e25eSJan Beulich	def_bool y
2611032c0baSSam Ravnborg
2621032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY
2631032c0baSSam Ravnborg	def_bool y
2641032c0baSSam Ravnborg
2659a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX
2669a0b8415Svenkatesh.pallipadi@intel.com	def_bool y
2678d5fffb9SSam Ravnborg
2681b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE
2691b27d05bSPekka Enberg	def_bool y
2701b27d05bSPekka Enberg
271dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA
27289c9c4c5SBrian Gerst	def_bool y
273b32ef636Stravis@sgi.com
27408fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK
27508fc4580STejun Heo	def_bool y
27608fc4580STejun Heo
27708fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK
27811124411STejun Heo	def_bool y
27911124411STejun Heo
280801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE
281801e4062SJohannes Berg	def_bool y
282801e4062SJohannes Berg
283f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE
284f4cb5700SJohannes Berg	def_bool y
285f4cb5700SJohannes Berg
286cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE
287cfe28c5dSSteve Capper	def_bool y
288cfe28c5dSSteve Capper
28953313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB
29053313b2cSSteve Capper	def_bool y
29153313b2cSSteve Capper
2928d5fffb9SSam Ravnborgconfig ZONE_DMA32
293e0fd24a3SJan Beulich	def_bool y if X86_64
2948d5fffb9SSam Ravnborg
2958d5fffb9SSam Ravnborgconfig AUDIT_ARCH
296e0fd24a3SJan Beulich	def_bool y if X86_64
2978d5fffb9SSam Ravnborg
298765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING
299765c68bdSIngo Molnar	def_bool y
300765c68bdSIngo Molnar
3016a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC
3026a11f75bSAkinobu Mita	def_bool y
3036a11f75bSAkinobu Mita
304d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET
305d6f2d75aSAndrey Ryabinin	hex
306d6f2d75aSAndrey Ryabinin	depends on KASAN
307d6f2d75aSAndrey Ryabinin	default 0xdffffc0000000000
308d6f2d75aSAndrey Ryabinin
30969575d38SShane Wangconfig HAVE_INTEL_TXT
31069575d38SShane Wang	def_bool y
3116ea30386SKees Cook	depends on INTEL_IOMMU && ACPI
31269575d38SShane Wang
3136b0c3d44SSam Ravnborgconfig X86_32_SMP
3146b0c3d44SSam Ravnborg	def_bool y
3156b0c3d44SSam Ravnborg	depends on X86_32 && SMP
3166b0c3d44SSam Ravnborg
3176b0c3d44SSam Ravnborgconfig X86_64_SMP
3186b0c3d44SSam Ravnborg	def_bool y
3196b0c3d44SSam Ravnborg	depends on X86_64 && SMP
3206b0c3d44SSam Ravnborg
321ccbeed3aSTejun Heoconfig X86_32_LAZY_GS
322ccbeed3aSTejun Heo	def_bool y
32360a5317fSTejun Heo	depends on X86_32 && !CC_STACKPROTECTOR
324ccbeed3aSTejun Heo
3252b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES
3262b144498SSrikar Dronamraju	def_bool y
3272b144498SSrikar Dronamraju
328d20642f0SRob Herringconfig FIX_EARLYCON_MEM
329d20642f0SRob Herring	def_bool y
330d20642f0SRob Herring
33198233368SKirill A. Shutemovconfig PGTABLE_LEVELS
33298233368SKirill A. Shutemov	int
33377ef56e4SKirill A. Shutemov	default 5 if X86_5LEVEL
33498233368SKirill A. Shutemov	default 4 if X86_64
33598233368SKirill A. Shutemov	default 3 if X86_PAE
33698233368SKirill A. Shutemov	default 2
33798233368SKirill A. Shutemov
338506f1d07SSam Ravnborgsource "init/Kconfig"
339dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer"
3408d5fffb9SSam Ravnborg
341506f1d07SSam Ravnborgmenu "Processor type and features"
342506f1d07SSam Ravnborg
3435ee71535SRandy Dunlapconfig ZONE_DMA
3445ee71535SRandy Dunlap	bool "DMA memory allocation support" if EXPERT
3455ee71535SRandy Dunlap	default y
3465ee71535SRandy Dunlap	help
3475ee71535SRandy Dunlap	  DMA memory allocation support allows devices with less than 32-bit
3485ee71535SRandy Dunlap	  addressing to allocate within the first 16MB of address space.
3495ee71535SRandy Dunlap	  Disable if no such devices will be used.
3505ee71535SRandy Dunlap
3515ee71535SRandy Dunlap	  If unsure, say Y.
3525ee71535SRandy Dunlap
353506f1d07SSam Ravnborgconfig SMP
354506f1d07SSam Ravnborg	bool "Symmetric multi-processing support"
355506f1d07SSam Ravnborg	---help---
356506f1d07SSam Ravnborg	  This enables support for systems with more than one CPU. If you have
3574a474157SRobert Graffham	  a system with only one CPU, say N. If you have a system with more
3584a474157SRobert Graffham	  than one CPU, say Y.
359506f1d07SSam Ravnborg
3604a474157SRobert Graffham	  If you say N here, the kernel will run on uni- and multiprocessor
361506f1d07SSam Ravnborg	  machines, but will use only one CPU of a multiprocessor machine. If
362506f1d07SSam Ravnborg	  you say Y here, the kernel will run on many, but not all,
3634a474157SRobert Graffham	  uniprocessor machines. On a uniprocessor machine, the kernel
364506f1d07SSam Ravnborg	  will run faster if you say N here.
365506f1d07SSam Ravnborg
366506f1d07SSam Ravnborg	  Note that if you say Y here and choose architecture "586" or
367506f1d07SSam Ravnborg	  "Pentium" under "Processor family", the kernel will not work on 486
368506f1d07SSam Ravnborg	  architectures. Similarly, multiprocessor kernels for the "PPro"
369506f1d07SSam Ravnborg	  architecture may not work on all Pentium based boards.
370506f1d07SSam Ravnborg
371506f1d07SSam Ravnborg	  People using multiprocessor machines who say Y here should also say
372506f1d07SSam Ravnborg	  Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
373506f1d07SSam Ravnborg	  Management" code will be disabled if you say Y here.
374506f1d07SSam Ravnborg
375395cf969SPaul Bolle	  See also <file:Documentation/x86/i386/IO-APIC.txt>,
376c9525a3fSBenjamin Peterson	  <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
377506f1d07SSam Ravnborg	  <http://www.tldp.org/docs.html#howto>.
378506f1d07SSam Ravnborg
379506f1d07SSam Ravnborg	  If you don't know what to do here, say N.
380506f1d07SSam Ravnborg
3819def39beSJosh Triplettconfig X86_FEATURE_NAMES
3829def39beSJosh Triplett	bool "Processor feature human-readable names" if EMBEDDED
3839def39beSJosh Triplett	default y
3849def39beSJosh Triplett	---help---
3859def39beSJosh Triplett	  This option compiles in a table of x86 feature bits and corresponding
3869def39beSJosh Triplett	  names.  This is required to support /proc/cpuinfo and a few kernel
3879def39beSJosh Triplett	  messages.  You can disable this to save space, at the expense of
3889def39beSJosh Triplett	  making those few kernel messages show numeric feature bits instead.
3899def39beSJosh Triplett
3909def39beSJosh Triplett	  If in doubt, say Y.
3919def39beSJosh Triplett
3926e1315feSBorislav Petkovconfig X86_FAST_FEATURE_TESTS
3936e1315feSBorislav Petkov	bool "Fast CPU feature tests" if EMBEDDED
3946e1315feSBorislav Petkov	default y
3956e1315feSBorislav Petkov	---help---
3966e1315feSBorislav Petkov	  Some fast-paths in the kernel depend on the capabilities of the CPU.
3976e1315feSBorislav Petkov	  Say Y here for the kernel to patch in the appropriate code at runtime
3986e1315feSBorislav Petkov	  based on the capabilities of the CPU. The infrastructure for patching
3996e1315feSBorislav Petkov	  code at runtime takes up some additional space; space-constrained
4006e1315feSBorislav Petkov	  embedded systems may wish to say N here to produce smaller, slightly
4016e1315feSBorislav Petkov	  slower code.
4026e1315feSBorislav Petkov
40306cd9a7dSYinghai Luconfig X86_X2APIC
40406cd9a7dSYinghai Lu	bool "Support x2apic"
40519e3d60dSJan Kiszka	depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
40606cd9a7dSYinghai Lu	---help---
40706cd9a7dSYinghai Lu	  This enables x2apic support on CPUs that have this feature.
40806cd9a7dSYinghai Lu
40906cd9a7dSYinghai Lu	  This allows 32-bit apic IDs (so it can support very large systems),
41006cd9a7dSYinghai Lu	  and accesses the local apic via MSRs not via mmio.
41106cd9a7dSYinghai Lu
41206cd9a7dSYinghai Lu	  If you don't know what to do here, say N.
41306cd9a7dSYinghai Lu
4146695c85bSYinghai Luconfig X86_MPPARSE
4156e87f9b7SBin Gao	bool "Enable MPS table" if ACPI || SFI
4167a527688SJan Beulich	default y
4175ab74722SIngo Molnar	depends on X86_LOCAL_APIC
4188f9ca475SIngo Molnar	---help---
4196695c85bSYinghai Lu	  For old smp systems that do not have proper acpi support. Newer systems
4206695c85bSYinghai Lu	  (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
4216695c85bSYinghai Lu
42226f7ef14SYinghai Luconfig X86_BIGSMP
42326f7ef14SYinghai Lu	bool "Support for big SMP systems with more than 8 CPUs"
42426f7ef14SYinghai Lu	depends on X86_32 && SMP
4258f9ca475SIngo Molnar	---help---
42626f7ef14SYinghai Lu	  This option is needed for the systems that have more than 8 CPUs
427506f1d07SSam Ravnborg
428ddd70cf9SJun Nakajimaconfig GOLDFISH
429ddd70cf9SJun Nakajima       def_bool y
430ddd70cf9SJun Nakajima       depends on X86_GOLDFISH
431ddd70cf9SJun Nakajima
432*76b04384SDavid Woodhouseconfig RETPOLINE
433*76b04384SDavid Woodhouse	bool "Avoid speculative indirect branches in kernel"
434*76b04384SDavid Woodhouse	default y
435*76b04384SDavid Woodhouse	help
436*76b04384SDavid Woodhouse	  Compile kernel with the retpoline compiler options to guard against
437*76b04384SDavid Woodhouse	  kernel-to-user data leaks by avoiding speculative indirect
438*76b04384SDavid Woodhouse	  branches. Requires a compiler with -mindirect-branch=thunk-extern
439*76b04384SDavid Woodhouse	  support for full protection. The kernel may run slower.
440*76b04384SDavid Woodhouse
441*76b04384SDavid Woodhouse	  Without compiler support, at least indirect branches in assembler
442*76b04384SDavid Woodhouse	  code are eliminated. Since this includes the syscall entry path,
443*76b04384SDavid Woodhouse	  it is not entirely pointless.
444*76b04384SDavid Woodhouse
445f01d7d51SVikas Shivappaconfig INTEL_RDT
446f01d7d51SVikas Shivappa	bool "Intel Resource Director Technology support"
44778e99b4aSFenghua Yu	default n
44878e99b4aSFenghua Yu	depends on X86 && CPU_SUP_INTEL
44959fe5a77SThomas Gleixner	select KERNFS
45078e99b4aSFenghua Yu	help
451f01d7d51SVikas Shivappa	  Select to enable resource allocation and monitoring which are
452f01d7d51SVikas Shivappa	  sub-features of Intel Resource Director Technology(RDT). More
453f01d7d51SVikas Shivappa	  information about RDT can be found in the Intel x86
454f01d7d51SVikas Shivappa	  Architecture Software Developer Manual.
45578e99b4aSFenghua Yu
45678e99b4aSFenghua Yu	  Say N if unsure.
45778e99b4aSFenghua Yu
4588425091fSRavikiran G Thirumalaiif X86_32
459c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM
460c5c606d9SRavikiran G Thirumalai	bool "Support for extended (non-PC) x86 platforms"
461c5c606d9SRavikiran G Thirumalai	default y
4628f9ca475SIngo Molnar	---help---
46306ac8346SIngo Molnar	  If you disable this option then the kernel will only support
46406ac8346SIngo Molnar	  standard PC platforms. (which covers the vast majority of
46506ac8346SIngo Molnar	  systems out there.)
46606ac8346SIngo Molnar
4678425091fSRavikiran G Thirumalai	  If you enable this option then you'll be able to select support
4688425091fSRavikiran G Thirumalai	  for the following (non-PC) 32 bit x86 platforms:
469cb7b8023SBen Hutchings		Goldfish (Android emulator)
4708425091fSRavikiran G Thirumalai		AMD Elan
4718425091fSRavikiran G Thirumalai		RDC R-321x SoC
4728425091fSRavikiran G Thirumalai		SGI 320/540 (Visual Workstation)
47383125a3aSAlessandro Rubini		STA2X11-based (e.g. Northville)
4743f4110a4SThomas Gleixner		Moorestown MID devices
47506ac8346SIngo Molnar
47606ac8346SIngo Molnar	  If you have one of these systems, or if you want to build a
47706ac8346SIngo Molnar	  generic distribution kernel, say Y here - otherwise say N.
4788425091fSRavikiran G Thirumalaiendif
47906ac8346SIngo Molnar
4808425091fSRavikiran G Thirumalaiif X86_64
4818425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM
4828425091fSRavikiran G Thirumalai	bool "Support for extended (non-PC) x86 platforms"
4838425091fSRavikiran G Thirumalai	default y
4848425091fSRavikiran G Thirumalai	---help---
4858425091fSRavikiran G Thirumalai	  If you disable this option then the kernel will only support
4868425091fSRavikiran G Thirumalai	  standard PC platforms. (which covers the vast majority of
4878425091fSRavikiran G Thirumalai	  systems out there.)
4888425091fSRavikiran G Thirumalai
4898425091fSRavikiran G Thirumalai	  If you enable this option then you'll be able to select support
4908425091fSRavikiran G Thirumalai	  for the following (non-PC) 64 bit x86 platforms:
49144b111b5SSteffen Persvold		Numascale NumaChip
4928425091fSRavikiran G Thirumalai		ScaleMP vSMP
4938425091fSRavikiran G Thirumalai		SGI Ultraviolet
4948425091fSRavikiran G Thirumalai
4958425091fSRavikiran G Thirumalai	  If you have one of these systems, or if you want to build a
4968425091fSRavikiran G Thirumalai	  generic distribution kernel, say Y here - otherwise say N.
4978425091fSRavikiran G Thirumalaiendif
498c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms
499c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions
50044b111b5SSteffen Persvoldconfig X86_NUMACHIP
50144b111b5SSteffen Persvold	bool "Numascale NumaChip"
50244b111b5SSteffen Persvold	depends on X86_64
50344b111b5SSteffen Persvold	depends on X86_EXTENDED_PLATFORM
50444b111b5SSteffen Persvold	depends on NUMA
50544b111b5SSteffen Persvold	depends on SMP
50644b111b5SSteffen Persvold	depends on X86_X2APIC
507f9726bfdSDaniel J Blueman	depends on PCI_MMCONFIG
50844b111b5SSteffen Persvold	---help---
50944b111b5SSteffen Persvold	  Adds support for Numascale NumaChip large-SMP systems. Needed to
51044b111b5SSteffen Persvold	  enable more than ~168 cores.
51144b111b5SSteffen Persvold	  If you don't have one of these, you should say N here.
51203b48632SNick Piggin
5136a48565eSIngo Molnarconfig X86_VSMP
514c5c606d9SRavikiran G Thirumalai	bool "ScaleMP vSMP"
5156276a074SBorislav Petkov	select HYPERVISOR_GUEST
5166a48565eSIngo Molnar	select PARAVIRT
5176a48565eSIngo Molnar	depends on X86_64 && PCI
518c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
519ead91d4bSShai Fultheim	depends on SMP
5208f9ca475SIngo Molnar	---help---
5216a48565eSIngo Molnar	  Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
5226a48565eSIngo Molnar	  supposed to run on these EM64T-based machines.  Only choose this option
5236a48565eSIngo Molnar	  if you have one of these machines.
5246a48565eSIngo Molnar
525c5c606d9SRavikiran G Thirumalaiconfig X86_UV
526c5c606d9SRavikiran G Thirumalai	bool "SGI Ultraviolet"
527c5c606d9SRavikiran G Thirumalai	depends on X86_64
528c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
52954c28d29SJack Steiner	depends on NUMA
5301ecb4ae5SAndrew Morton	depends on EFI
5319d6c26e7SSuresh Siddha	depends on X86_X2APIC
5321222e564SIngo Molnar	depends on PCI
533c5c606d9SRavikiran G Thirumalai	---help---
534c5c606d9SRavikiran G Thirumalai	  This option is needed in order to support SGI Ultraviolet systems.
535c5c606d9SRavikiran G Thirumalai	  If you don't have one of these, you should say N here.
536c5c606d9SRavikiran G Thirumalai
537c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms
538c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions
539506f1d07SSam Ravnborg
540ddd70cf9SJun Nakajimaconfig X86_GOLDFISH
541ddd70cf9SJun Nakajima       bool "Goldfish (Virtual Platform)"
542cb7b8023SBen Hutchings       depends on X86_EXTENDED_PLATFORM
543ddd70cf9SJun Nakajima       ---help---
544ddd70cf9SJun Nakajima	 Enable support for the Goldfish virtual platform used primarily
545ddd70cf9SJun Nakajima	 for Android development. Unless you are building for the Android
546ddd70cf9SJun Nakajima	 Goldfish emulator say N here.
547ddd70cf9SJun Nakajima
548c751e17bSThomas Gleixnerconfig X86_INTEL_CE
549c751e17bSThomas Gleixner	bool "CE4100 TV platform"
550c751e17bSThomas Gleixner	depends on PCI
551c751e17bSThomas Gleixner	depends on PCI_GODIRECT
5526084a6e2SJiang Liu	depends on X86_IO_APIC
553c751e17bSThomas Gleixner	depends on X86_32
554c751e17bSThomas Gleixner	depends on X86_EXTENDED_PLATFORM
55537bc9f50SDirk Brandewie	select X86_REBOOTFIXUPS
556da6b737bSSebastian Andrzej Siewior	select OF
557da6b737bSSebastian Andrzej Siewior	select OF_EARLY_FLATTREE
558c751e17bSThomas Gleixner	---help---
559c751e17bSThomas Gleixner	  Select for the Intel CE media processor (CE4100) SOC.
560c751e17bSThomas Gleixner	  This option compiles in support for the CE4100 SOC for settop
561c751e17bSThomas Gleixner	  boxes and media devices.
562c751e17bSThomas Gleixner
5634cb9b00fSDavid Cohenconfig X86_INTEL_MID
56443605ef1SAlan Cox	bool "Intel MID platform support"
56543605ef1SAlan Cox	depends on X86_EXTENDED_PLATFORM
566edc6bc78SDavid Cohen	depends on X86_PLATFORM_DEVICES
5671ea7c673SAlan Cox	depends on PCI
5683fda5bb4SAndy Shevchenko	depends on X86_64 || (PCI_GOANY && X86_32)
5691ea7c673SAlan Cox	depends on X86_IO_APIC
5707c9c3a1eSAlan Cox	select SFI
5714cb9b00fSDavid Cohen	select I2C
5727c9c3a1eSAlan Cox	select DW_APB_TIMER
5731ea7c673SAlan Cox	select APB_TIMER
5741ea7c673SAlan Cox	select INTEL_SCU_IPC
57515a713dfSMika Westerberg	select MFD_INTEL_MSIC
5761ea7c673SAlan Cox	---help---
5774cb9b00fSDavid Cohen	  Select to build a kernel capable of supporting Intel MID (Mobile
5784cb9b00fSDavid Cohen	  Internet Device) platform systems which do not have the PCI legacy
5794cb9b00fSDavid Cohen	  interfaces. If you are building for a PC class system say N here.
5801ea7c673SAlan Cox
5814cb9b00fSDavid Cohen	  Intel MID platforms are based on an Intel processor and chipset which
5824cb9b00fSDavid Cohen	  consume less power than most of the x86 derivatives.
58343605ef1SAlan Cox
5848bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK
5858bbc2a13SBryan O'Donoghue	bool "Intel Quark platform support"
5868bbc2a13SBryan O'Donoghue	depends on X86_32
5878bbc2a13SBryan O'Donoghue	depends on X86_EXTENDED_PLATFORM
5888bbc2a13SBryan O'Donoghue	depends on X86_PLATFORM_DEVICES
5898bbc2a13SBryan O'Donoghue	depends on X86_TSC
5908bbc2a13SBryan O'Donoghue	depends on PCI
5918bbc2a13SBryan O'Donoghue	depends on PCI_GOANY
5928bbc2a13SBryan O'Donoghue	depends on X86_IO_APIC
5938bbc2a13SBryan O'Donoghue	select IOSF_MBI
5948bbc2a13SBryan O'Donoghue	select INTEL_IMR
5959ab6eb51SAndy Shevchenko	select COMMON_CLK
5968bbc2a13SBryan O'Donoghue	---help---
5978bbc2a13SBryan O'Donoghue	  Select to include support for Quark X1000 SoC.
5988bbc2a13SBryan O'Donoghue	  Say Y here if you have a Quark based system such as the Arduino
5998bbc2a13SBryan O'Donoghue	  compatible Intel Galileo.
6008bbc2a13SBryan O'Donoghue
6013d48aab1SMika Westerbergconfig X86_INTEL_LPSS
6023d48aab1SMika Westerberg	bool "Intel Low Power Subsystem Support"
603eebb3e8dSAndy Shevchenko	depends on X86 && ACPI
6043d48aab1SMika Westerberg	select COMMON_CLK
6050f531431SMathias Nyman	select PINCTRL
606eebb3e8dSAndy Shevchenko	select IOSF_MBI
6073d48aab1SMika Westerberg	---help---
6083d48aab1SMika Westerberg	  Select to build support for Intel Low Power Subsystem such as
6093d48aab1SMika Westerberg	  found on Intel Lynxpoint PCH. Selecting this option enables
6100f531431SMathias Nyman	  things like clock tree (common clock framework) and pincontrol
6110f531431SMathias Nyman	  which are needed by the LPSS peripheral drivers.
6123d48aab1SMika Westerberg
61392082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE
61492082a88SKen Xue	bool "AMD ACPI2Platform devices support"
61592082a88SKen Xue	depends on ACPI
61692082a88SKen Xue	select COMMON_CLK
61792082a88SKen Xue	select PINCTRL
61892082a88SKen Xue	---help---
61992082a88SKen Xue	  Select to interpret AMD specific ACPI device to platform device
62092082a88SKen Xue	  such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
62192082a88SKen Xue	  I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
62292082a88SKen Xue	  implemented under PINCTRL subsystem.
62392082a88SKen Xue
624ced3ce76SDavid E. Boxconfig IOSF_MBI
625ced3ce76SDavid E. Box	tristate "Intel SoC IOSF Sideband support for SoC platforms"
626ced3ce76SDavid E. Box	depends on PCI
627ced3ce76SDavid E. Box	---help---
628ced3ce76SDavid E. Box	  This option enables sideband register access support for Intel SoC
629ced3ce76SDavid E. Box	  platforms. On these platforms the IOSF sideband is used in lieu of
630ced3ce76SDavid E. Box	  MSR's for some register accesses, mostly but not limited to thermal
631ced3ce76SDavid E. Box	  and power. Drivers may query the availability of this device to
632ced3ce76SDavid E. Box	  determine if they need the sideband in order to work on these
633ced3ce76SDavid E. Box	  platforms. The sideband is available on the following SoC products.
634ced3ce76SDavid E. Box	  This list is not meant to be exclusive.
635ced3ce76SDavid E. Box	   - BayTrail
636ced3ce76SDavid E. Box	   - Braswell
637ced3ce76SDavid E. Box	   - Quark
638ced3ce76SDavid E. Box
639ced3ce76SDavid E. Box	  You should say Y if you are running a kernel on one of these SoC's.
640ced3ce76SDavid E. Box
641ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG
642ed2226bdSDavid E. Box	bool "Enable IOSF sideband access through debugfs"
643ed2226bdSDavid E. Box	depends on IOSF_MBI && DEBUG_FS
644ed2226bdSDavid E. Box	---help---
645ed2226bdSDavid E. Box	  Select this option to expose the IOSF sideband access registers (MCR,
646ed2226bdSDavid E. Box	  MDR, MCRX) through debugfs to write and read register information from
647ed2226bdSDavid E. Box	  different units on the SoC. This is most useful for obtaining device
648ed2226bdSDavid E. Box	  state information for debug and analysis. As this is a general access
649ed2226bdSDavid E. Box	  mechanism, users of this option would have specific knowledge of the
650ed2226bdSDavid E. Box	  device they want to access.
651ed2226bdSDavid E. Box
652ed2226bdSDavid E. Box	  If you don't require the option or are in doubt, say N.
653ed2226bdSDavid E. Box
654c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X
655c5c606d9SRavikiran G Thirumalai	bool "RDC R-321x SoC"
656506f1d07SSam Ravnborg	depends on X86_32
657c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
658c5c606d9SRavikiran G Thirumalai	select M486
659c5c606d9SRavikiran G Thirumalai	select X86_REBOOTFIXUPS
660c5c606d9SRavikiran G Thirumalai	---help---
661c5c606d9SRavikiran G Thirumalai	  This option is needed for RDC R-321x system-on-chip, also known
662c5c606d9SRavikiran G Thirumalai	  as R-8610-(G).
663c5c606d9SRavikiran G Thirumalai	  If you don't have one of these chips, you should say N here.
664c5c606d9SRavikiran G Thirumalai
665e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD
6669c398017SIngo Molnar	bool "Support non-standard 32-bit SMP architectures"
6679c398017SIngo Molnar	depends on X86_32 && SMP
668c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
6698f9ca475SIngo Molnar	---help---
670b5660ba7SH. Peter Anvin	  This option compiles in the bigsmp and STA2X11 default
671b5660ba7SH. Peter Anvin	  subarchitectures.  It is intended for a generic binary
672b5660ba7SH. Peter Anvin	  kernel. If you select them all, kernel will probe it one by
673b5660ba7SH. Peter Anvin	  one and will fallback to default.
674d49c4288SYinghai Lu
675c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms
676d49c4288SYinghai Lu
677d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE
6786fc108a0SJan Beulich	def_bool y
679d949f36fSLinus Torvalds	# MCE code calls memory_failure():
680d949f36fSLinus Torvalds	depends on X86_MCE
681d949f36fSLinus Torvalds	# On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
682d949f36fSLinus Torvalds	# On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
683d949f36fSLinus Torvalds	depends on X86_64 || !SPARSEMEM
684d949f36fSLinus Torvalds	select ARCH_SUPPORTS_MEMORY_FAILURE
685d949f36fSLinus Torvalds
68683125a3aSAlessandro Rubiniconfig STA2X11
68783125a3aSAlessandro Rubini	bool "STA2X11 Companion Chip Support"
68883125a3aSAlessandro Rubini	depends on X86_32_NON_STANDARD && PCI
68983125a3aSAlessandro Rubini	select X86_DEV_DMA_OPS
69083125a3aSAlessandro Rubini	select X86_DMA_REMAP
69183125a3aSAlessandro Rubini	select SWIOTLB
69283125a3aSAlessandro Rubini	select MFD_STA2X11
6930145071bSLinus Walleij	select GPIOLIB
69483125a3aSAlessandro Rubini	default n
69583125a3aSAlessandro Rubini	---help---
69683125a3aSAlessandro Rubini	  This adds support for boards based on the STA2X11 IO-Hub,
69783125a3aSAlessandro Rubini	  a.k.a. "ConneXt". The chip is used in place of the standard
69883125a3aSAlessandro Rubini	  PC chipset, so all "standard" peripherals are missing. If this
69983125a3aSAlessandro Rubini	  option is selected the kernel will still be able to boot on
70083125a3aSAlessandro Rubini	  standard PC machines.
70183125a3aSAlessandro Rubini
70282148d1dSShérabconfig X86_32_IRIS
70382148d1dSShérab	tristate "Eurobraille/Iris poweroff module"
70482148d1dSShérab	depends on X86_32
70582148d1dSShérab	---help---
70682148d1dSShérab	  The Iris machines from EuroBraille do not have APM or ACPI support
70782148d1dSShérab	  to shut themselves down properly.  A special I/O sequence is
70882148d1dSShérab	  needed to do so, which is what this module does at
70982148d1dSShérab	  kernel shutdown.
71082148d1dSShérab
71182148d1dSShérab	  This is only for Iris machines from EuroBraille.
71282148d1dSShérab
71382148d1dSShérab	  If unused, say N.
71482148d1dSShérab
715ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER
7163c2362e6SHarvey Harrison	def_bool y
7173c2362e6SHarvey Harrison	prompt "Single-depth WCHAN output"
718a87d0914SKen Chen	depends on X86
7198f9ca475SIngo Molnar	---help---
720506f1d07SSam Ravnborg	  Calculate simpler /proc/<PID>/wchan values. If this option
721506f1d07SSam Ravnborg	  is disabled then wchan values will recurse back to the
722506f1d07SSam Ravnborg	  caller function. This provides more accurate wchan values,
723506f1d07SSam Ravnborg	  at the expense of slightly more scheduling overhead.
724506f1d07SSam Ravnborg
725506f1d07SSam Ravnborg	  If in doubt, say "Y".
726506f1d07SSam Ravnborg
7276276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST
7286276a074SBorislav Petkov	bool "Linux guest support"
7298f9ca475SIngo Molnar	---help---
7306276a074SBorislav Petkov	  Say Y here to enable options for running Linux under various hyper-
7316276a074SBorislav Petkov	  visors. This option enables basic hypervisor detection and platform
7326276a074SBorislav Petkov	  setup.
733506f1d07SSam Ravnborg
7346276a074SBorislav Petkov	  If you say N, all options in this submenu will be skipped and
7356276a074SBorislav Petkov	  disabled, and Linux guest support won't be built in.
736506f1d07SSam Ravnborg
7376276a074SBorislav Petkovif HYPERVISOR_GUEST
738506f1d07SSam Ravnborg
739e61bd94aSEduardo Pereira Habkostconfig PARAVIRT
740e61bd94aSEduardo Pereira Habkost	bool "Enable paravirtualization code"
7418f9ca475SIngo Molnar	---help---
742e61bd94aSEduardo Pereira Habkost	  This changes the kernel so it can modify itself when it is run
743e61bd94aSEduardo Pereira Habkost	  under a hypervisor, potentially improving performance significantly
744e61bd94aSEduardo Pereira Habkost	  over full virtualization.  However, when run without a hypervisor
745e61bd94aSEduardo Pereira Habkost	  the kernel is theoretically slower and slightly larger.
746e61bd94aSEduardo Pereira Habkost
7476276a074SBorislav Petkovconfig PARAVIRT_DEBUG
7486276a074SBorislav Petkov	bool "paravirt-ops debugging"
7496276a074SBorislav Petkov	depends on PARAVIRT && DEBUG_KERNEL
7506276a074SBorislav Petkov	---help---
7516276a074SBorislav Petkov	  Enable to debug paravirt_ops internals.  Specifically, BUG if
7526276a074SBorislav Petkov	  a paravirt_op is missing when it is called.
7536276a074SBorislav Petkov
754b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS
755b4ecc126SJeremy Fitzhardinge	bool "Paravirtualization layer for spinlocks"
7566ea30386SKees Cook	depends on PARAVIRT && SMP
757b4ecc126SJeremy Fitzhardinge	---help---
758b4ecc126SJeremy Fitzhardinge	  Paravirtualized spinlocks allow a pvops backend to replace the
759b4ecc126SJeremy Fitzhardinge	  spinlock implementation with something virtualization-friendly
760b4ecc126SJeremy Fitzhardinge	  (for example, block the virtual CPU rather than spinning).
761b4ecc126SJeremy Fitzhardinge
7624c4e4f61SRaghavendra K T	  It has a minimal impact on native kernels and gives a nice performance
7634c4e4f61SRaghavendra K T	  benefit on paravirtualized KVM / Xen kernels.
764b4ecc126SJeremy Fitzhardinge
7654c4e4f61SRaghavendra K T	  If you are unsure how to answer this question, answer Y.
766b4ecc126SJeremy Fitzhardinge
76745e898b7SWaiman Longconfig QUEUED_LOCK_STAT
76845e898b7SWaiman Long	bool "Paravirt queued spinlock statistics"
769cfd8983fSPeter Zijlstra	depends on PARAVIRT_SPINLOCKS && DEBUG_FS
77045e898b7SWaiman Long	---help---
77145e898b7SWaiman Long	  Enable the collection of statistical data on the slowpath
77245e898b7SWaiman Long	  behavior of paravirtualized queued spinlocks and report
77345e898b7SWaiman Long	  them on debugfs.
77445e898b7SWaiman Long
7756276a074SBorislav Petkovsource "arch/x86/xen/Kconfig"
7766276a074SBorislav Petkov
7776276a074SBorislav Petkovconfig KVM_GUEST
7786276a074SBorislav Petkov	bool "KVM Guest support (including kvmclock)"
7796276a074SBorislav Petkov	depends on PARAVIRT
7806276a074SBorislav Petkov	select PARAVIRT_CLOCK
7816276a074SBorislav Petkov	default y
7826276a074SBorislav Petkov	---help---
7836276a074SBorislav Petkov	  This option enables various optimizations for running under the KVM
7846276a074SBorislav Petkov	  hypervisor. It includes a paravirtualized clock, so that instead
7856276a074SBorislav Petkov	  of relying on a PIT (or probably other) emulation by the
7866276a074SBorislav Petkov	  underlying device model, the host provides the guest with
7876276a074SBorislav Petkov	  timing infrastructure such as time of day, and system time
7886276a074SBorislav Petkov
7891e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS
7901e20eb85SSrivatsa Vaddagiri	bool "Enable debug information for KVM Guests in debugfs"
7911e20eb85SSrivatsa Vaddagiri	depends on KVM_GUEST && DEBUG_FS
7921e20eb85SSrivatsa Vaddagiri	default n
7931e20eb85SSrivatsa Vaddagiri	---help---
7941e20eb85SSrivatsa Vaddagiri	  This option enables collection of various statistics for KVM guest.
7951e20eb85SSrivatsa Vaddagiri	  Statistics are displayed in debugfs filesystem. Enabling this option
7961e20eb85SSrivatsa Vaddagiri	  may incur significant overhead.
7971e20eb85SSrivatsa Vaddagiri
7986276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING
7996276a074SBorislav Petkov	bool "Paravirtual steal time accounting"
8006276a074SBorislav Petkov	depends on PARAVIRT
8016276a074SBorislav Petkov	default n
8026276a074SBorislav Petkov	---help---
8036276a074SBorislav Petkov	  Select this option to enable fine granularity task steal time
8046276a074SBorislav Petkov	  accounting. Time spent executing other tasks in parallel with
8056276a074SBorislav Petkov	  the current vCPU is discounted from the vCPU power. To account for
8066276a074SBorislav Petkov	  that, there can be a small performance impact.
8076276a074SBorislav Petkov
8086276a074SBorislav Petkov	  If in doubt, say N here.
8096276a074SBorislav Petkov
8107af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK
8117af192c9SGerd Hoffmann	bool
8127af192c9SGerd Hoffmann
8136276a074SBorislav Petkovendif #HYPERVISOR_GUEST
81497349135SJeremy Fitzhardinge
81508677214SYinghai Luconfig NO_BOOTMEM
816774ea0bcSYinghai Lu	def_bool y
81708677214SYinghai Lu
818506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu"
819506f1d07SSam Ravnborg
820506f1d07SSam Ravnborgconfig HPET_TIMER
8213c2362e6SHarvey Harrison	def_bool X86_64
822506f1d07SSam Ravnborg	prompt "HPET Timer Support" if X86_32
8238f9ca475SIngo Molnar	---help---
824506f1d07SSam Ravnborg	  Use the IA-PC HPET (High Precision Event Timer) to manage
825506f1d07SSam Ravnborg	  time in preference to the PIT and RTC, if a HPET is
826506f1d07SSam Ravnborg	  present.
827506f1d07SSam Ravnborg	  HPET is the next generation timer replacing legacy 8254s.
828506f1d07SSam Ravnborg	  The HPET provides a stable time base on SMP
829506f1d07SSam Ravnborg	  systems, unlike the TSC, but it is more expensive to access,
8304e7f9df2SMichael S. Tsirkin	  as it is off-chip.  The interface used is documented
8314e7f9df2SMichael S. Tsirkin	  in the HPET spec, revision 1.
832506f1d07SSam Ravnborg
833506f1d07SSam Ravnborg	  You can safely choose Y here.  However, HPET will only be
834506f1d07SSam Ravnborg	  activated if the platform and the BIOS support this feature.
835506f1d07SSam Ravnborg	  Otherwise the 8254 will be used for timing services.
836506f1d07SSam Ravnborg
837506f1d07SSam Ravnborg	  Choose N to continue using the legacy 8254 timer.
838506f1d07SSam Ravnborg
839506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC
8403c2362e6SHarvey Harrison	def_bool y
8419d8af78bSBernhard Walle	depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
842506f1d07SSam Ravnborg
843bb24c471SJacob Panconfig APB_TIMER
844933b9463SAlan Cox       def_bool y if X86_INTEL_MID
845933b9463SAlan Cox       prompt "Intel MID APB Timer Support" if X86_INTEL_MID
84606c3df49SJamie Iles       select DW_APB_TIMER
847a0c3832aSAlan Cox       depends on X86_INTEL_MID && SFI
848bb24c471SJacob Pan       help
849bb24c471SJacob Pan         APB timer is the replacement for 8254, HPET on X86 MID platforms.
850bb24c471SJacob Pan         The APBT provides a stable time base on SMP
851bb24c471SJacob Pan         systems, unlike the TSC, but it is more expensive to access,
852bb24c471SJacob Pan         as it is off-chip. APB timers are always running regardless of CPU
853bb24c471SJacob Pan         C states, they are used as per CPU clockevent device when possible.
854bb24c471SJacob Pan
8556a108a14SDavid Rientjes# Mark as expert because too many people got it wrong.
856506f1d07SSam Ravnborg# The code disables itself when not needed.
8577ae9392cSThomas Petazzoniconfig DMI
8587ae9392cSThomas Petazzoni	default y
859cf074402SArd Biesheuvel	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
8606a108a14SDavid Rientjes	bool "Enable DMI scanning" if EXPERT
8618f9ca475SIngo Molnar	---help---
8627ae9392cSThomas Petazzoni	  Enabled scanning of DMI to identify machine quirks. Say Y
8637ae9392cSThomas Petazzoni	  here unless you have verified that your setup is not
8647ae9392cSThomas Petazzoni	  affected by entries in the DMI blacklist. Required by PNP
8657ae9392cSThomas Petazzoni	  BIOS code.
8667ae9392cSThomas Petazzoni
867506f1d07SSam Ravnborgconfig GART_IOMMU
86838901f1cSAndi Kleen	bool "Old AMD GART IOMMU support"
869506f1d07SSam Ravnborg	select SWIOTLB
87023ac4ae8SAndreas Herrmann	depends on X86_64 && PCI && AMD_NB
8718f9ca475SIngo Molnar	---help---
872ced3c42cSIngo Molnar	  Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
873ced3c42cSIngo Molnar	  GART based hardware IOMMUs.
874ced3c42cSIngo Molnar
875ced3c42cSIngo Molnar	  The GART supports full DMA access for devices with 32-bit access
876ced3c42cSIngo Molnar	  limitations, on systems with more than 3 GB. This is usually needed
877ced3c42cSIngo Molnar	  for USB, sound, many IDE/SATA chipsets and some other devices.
878ced3c42cSIngo Molnar
879ced3c42cSIngo Molnar	  Newer systems typically have a modern AMD IOMMU, supported via
880ced3c42cSIngo Molnar	  the CONFIG_AMD_IOMMU=y config option.
881ced3c42cSIngo Molnar
882ced3c42cSIngo Molnar	  In normal configurations this driver is only active when needed:
883ced3c42cSIngo Molnar	  there's more than 3 GB of memory and the system contains a
884ced3c42cSIngo Molnar	  32-bit limited device.
885ced3c42cSIngo Molnar
886ced3c42cSIngo Molnar	  If unsure, say Y.
887506f1d07SSam Ravnborg
888506f1d07SSam Ravnborgconfig CALGARY_IOMMU
889506f1d07SSam Ravnborg	bool "IBM Calgary IOMMU support"
890506f1d07SSam Ravnborg	select SWIOTLB
8916ea30386SKees Cook	depends on X86_64 && PCI
8928f9ca475SIngo Molnar	---help---
893506f1d07SSam Ravnborg	  Support for hardware IOMMUs in IBM's xSeries x366 and x460
894506f1d07SSam Ravnborg	  systems. Needed to run systems with more than 3GB of memory
895506f1d07SSam Ravnborg	  properly with 32-bit PCI devices that do not support DAC
896506f1d07SSam Ravnborg	  (Double Address Cycle). Calgary also supports bus level
897506f1d07SSam Ravnborg	  isolation, where all DMAs pass through the IOMMU.  This
898506f1d07SSam Ravnborg	  prevents them from going anywhere except their intended
899506f1d07SSam Ravnborg	  destination. This catches hard-to-find kernel bugs and
900506f1d07SSam Ravnborg	  mis-behaving drivers and devices that do not use the DMA-API
901506f1d07SSam Ravnborg	  properly to set up their DMA buffers.  The IOMMU can be
902506f1d07SSam Ravnborg	  turned off at boot time with the iommu=off parameter.
903506f1d07SSam Ravnborg	  Normally the kernel will make the right choice by itself.
904506f1d07SSam Ravnborg	  If unsure, say Y.
905506f1d07SSam Ravnborg
906506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT
9073c2362e6SHarvey Harrison	def_bool y
9083c2362e6SHarvey Harrison	prompt "Should Calgary be enabled by default?"
909506f1d07SSam Ravnborg	depends on CALGARY_IOMMU
9108f9ca475SIngo Molnar	---help---
911506f1d07SSam Ravnborg	  Should Calgary be enabled by default? if you choose 'y', Calgary
912506f1d07SSam Ravnborg	  will be used (if it exists). If you choose 'n', Calgary will not be
913506f1d07SSam Ravnborg	  used even if it exists. If you choose 'n' and would like to use
914506f1d07SSam Ravnborg	  Calgary anyway, pass 'iommu=calgary' on the kernel command line.
915506f1d07SSam Ravnborg	  If unsure, say Y.
916506f1d07SSam Ravnborg
917506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround
918506f1d07SSam Ravnborgconfig SWIOTLB
919a1afd01cSJoerg Roedel	def_bool y if X86_64
9208f9ca475SIngo Molnar	---help---
921506f1d07SSam Ravnborg	  Support for software bounce buffers used on x86-64 systems
9224454d327SJoe Millenbach	  which don't have a hardware IOMMU. Using this PCI devices
9234454d327SJoe Millenbach	  which can only access 32-bits of memory can be used on systems
9244454d327SJoe Millenbach	  with more than 3 GB of memory.
9254454d327SJoe Millenbach	  If unsure, say Y.
926506f1d07SSam Ravnborg
927a8522509SFUJITA Tomonoriconfig IOMMU_HELPER
9283120e25eSJan Beulich	def_bool y
9293120e25eSJan Beulich	depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
930d25e26b6SLinus Torvalds
9311184dc2fSMike Travisconfig MAXSMP
932ddb0c5a6SSamuel Thibault	bool "Enable Maximum number of SMP Processors and NUMA Nodes"
9336ea30386SKees Cook	depends on X86_64 && SMP && DEBUG_KERNEL
93436f5101aSMike Travis	select CPUMASK_OFFSTACK
9358f9ca475SIngo Molnar	---help---
936ddb0c5a6SSamuel Thibault	  Enable maximum number of CPUS and NUMA Nodes for this architecture.
9371184dc2fSMike Travis	  If unsure, say N.
938506f1d07SSam Ravnborg
939506f1d07SSam Ravnborgconfig NR_CPUS
94036f5101aSMike Travis	int "Maximum number of CPUs" if SMP && !MAXSMP
9412a3313f4SMichael K. Johnson	range 2 8 if SMP && X86_32 && !X86_BIGSMP
9427bbcbd3dSThomas Gleixner	range 2 64 if SMP && X86_32 && X86_BIGSMP
9437bbcbd3dSThomas Gleixner	range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK && X86_64
944b53b5edaSJosh Boyer	range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
94578637a97SMike Travis	default "1" if !SMP
946b53b5edaSJosh Boyer	default "8192" if MAXSMP
947b5660ba7SH. Peter Anvin	default "32" if SMP && X86_BIGSMP
948c5c19941SKirill A. Shutemov	default "8" if SMP && X86_32
949c5c19941SKirill A. Shutemov	default "64" if SMP
9508f9ca475SIngo Molnar	---help---
951506f1d07SSam Ravnborg	  This allows you to specify the maximum number of CPUs which this
952bb61ccc7SJosh Boyer	  kernel will support.  If CPUMASK_OFFSTACK is enabled, the maximum
953cad14bb9SKirill A. Shutemov	  supported value is 8192, otherwise the maximum value is 512.  The
954506f1d07SSam Ravnborg	  minimum value which makes sense is 2.
955506f1d07SSam Ravnborg
956506f1d07SSam Ravnborg	  This is purely to save memory - each supported CPU adds
957506f1d07SSam Ravnborg	  approximately eight kilobytes to the kernel image.
958506f1d07SSam Ravnborg
959506f1d07SSam Ravnborgconfig SCHED_SMT
960506f1d07SSam Ravnborg	bool "SMT (Hyperthreading) scheduler support"
961c8e56d20SBorislav Petkov	depends on SMP
9628f9ca475SIngo Molnar	---help---
963506f1d07SSam Ravnborg	  SMT scheduler support improves the CPU scheduler's decision making
964506f1d07SSam Ravnborg	  when dealing with Intel Pentium 4 chips with HyperThreading at a
965506f1d07SSam Ravnborg	  cost of slightly increased overhead in some places. If unsure say
966506f1d07SSam Ravnborg	  N here.
967506f1d07SSam Ravnborg
968506f1d07SSam Ravnborgconfig SCHED_MC
9693c2362e6SHarvey Harrison	def_bool y
9703c2362e6SHarvey Harrison	prompt "Multi-core scheduler support"
971c8e56d20SBorislav Petkov	depends on SMP
9728f9ca475SIngo Molnar	---help---
973506f1d07SSam Ravnborg	  Multi-core scheduler support improves the CPU scheduler's decision
974506f1d07SSam Ravnborg	  making when dealing with multi-core CPU chips at a cost of slightly
975506f1d07SSam Ravnborg	  increased overhead in some places. If unsure say N here.
976506f1d07SSam Ravnborg
977de966cf4STim Chenconfig SCHED_MC_PRIO
978de966cf4STim Chen	bool "CPU core priorities scheduler support"
9790a21fc12SIngo Molnar	depends on SCHED_MC && CPU_SUP_INTEL
9800a21fc12SIngo Molnar	select X86_INTEL_PSTATE
9810a21fc12SIngo Molnar	select CPU_FREQ
982de966cf4STim Chen	default y
9835e76b2abSTim Chen	---help---
984de966cf4STim Chen	  Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
985de966cf4STim Chen	  core ordering determined at manufacturing time, which allows
986de966cf4STim Chen	  certain cores to reach higher turbo frequencies (when running
987de966cf4STim Chen	  single threaded workloads) than others.
988de966cf4STim Chen
989de966cf4STim Chen	  Enabling this kernel feature teaches the scheduler about
990de966cf4STim Chen	  the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
991de966cf4STim Chen	  scheduler's CPU selection logic accordingly, so that higher
992de966cf4STim Chen	  overall system performance can be achieved.
993de966cf4STim Chen
994de966cf4STim Chen	  This feature will have no effect on CPUs without this feature.
995de966cf4STim Chen
996de966cf4STim Chen	  If unsure say Y here.
9975e76b2abSTim Chen
998506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt"
999506f1d07SSam Ravnborg
100030b8b006SThomas Gleixnerconfig UP_LATE_INIT
100130b8b006SThomas Gleixner       def_bool y
1002ba360f88SThomas Gleixner       depends on !SMP && X86_LOCAL_APIC
100330b8b006SThomas Gleixner
1004506f1d07SSam Ravnborgconfig X86_UP_APIC
100550849eefSJan Beulich	bool "Local APIC support on uniprocessors" if !PCI_MSI
100650849eefSJan Beulich	default PCI_MSI
100738a1dfdaSBryan O'Donoghue	depends on X86_32 && !SMP && !X86_32_NON_STANDARD
10088f9ca475SIngo Molnar	---help---
1009506f1d07SSam Ravnborg	  A local APIC (Advanced Programmable Interrupt Controller) is an
1010506f1d07SSam Ravnborg	  integrated interrupt controller in the CPU. If you have a single-CPU
1011506f1d07SSam Ravnborg	  system which has a processor with a local APIC, you can say Y here to
1012506f1d07SSam Ravnborg	  enable and use it. If you say Y here even though your machine doesn't
1013506f1d07SSam Ravnborg	  have a local APIC, then the kernel will still run with no slowdown at
1014506f1d07SSam Ravnborg	  all. The local APIC supports CPU-generated self-interrupts (timer,
1015506f1d07SSam Ravnborg	  performance counters), and the NMI watchdog which detects hard
1016506f1d07SSam Ravnborg	  lockups.
1017506f1d07SSam Ravnborg
1018506f1d07SSam Ravnborgconfig X86_UP_IOAPIC
1019506f1d07SSam Ravnborg	bool "IO-APIC support on uniprocessors"
1020506f1d07SSam Ravnborg	depends on X86_UP_APIC
10218f9ca475SIngo Molnar	---help---
1022506f1d07SSam Ravnborg	  An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1023506f1d07SSam Ravnborg	  SMP-capable replacement for PC-style interrupt controllers. Most
1024506f1d07SSam Ravnborg	  SMP systems and many recent uniprocessor systems have one.
1025506f1d07SSam Ravnborg
1026506f1d07SSam Ravnborg	  If you have a single-CPU system with an IO-APIC, you can say Y here
1027506f1d07SSam Ravnborg	  to use it. If you say Y here even though your machine doesn't have
1028506f1d07SSam Ravnborg	  an IO-APIC, then the kernel will still run with no slowdown at all.
1029506f1d07SSam Ravnborg
1030506f1d07SSam Ravnborgconfig X86_LOCAL_APIC
10313c2362e6SHarvey Harrison	def_bool y
10320dbc6078SThomas Petazzoni	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
1033b5dc8e6cSJiang Liu	select IRQ_DOMAIN_HIERARCHY
103452f518a3SJiang Liu	select PCI_MSI_IRQ_DOMAIN if PCI_MSI
1035506f1d07SSam Ravnborg
1036506f1d07SSam Ravnborgconfig X86_IO_APIC
1037b1da1e71SJan Beulich	def_bool y
1038b1da1e71SJan Beulich	depends on X86_LOCAL_APIC || X86_UP_IOAPIC
1039506f1d07SSam Ravnborg
104041b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS
104141b9eb26SStefan Assmann	bool "Reroute for broken boot IRQs"
104241b9eb26SStefan Assmann	depends on X86_IO_APIC
10438f9ca475SIngo Molnar	---help---
104441b9eb26SStefan Assmann	  This option enables a workaround that fixes a source of
104541b9eb26SStefan Assmann	  spurious interrupts. This is recommended when threaded
104641b9eb26SStefan Assmann	  interrupt handling is used on systems where the generation of
104741b9eb26SStefan Assmann	  superfluous "boot interrupts" cannot be disabled.
104841b9eb26SStefan Assmann
104941b9eb26SStefan Assmann	  Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
105041b9eb26SStefan Assmann	  entry in the chipset's IO-APIC is masked (as, e.g. the RT
105141b9eb26SStefan Assmann	  kernel does during interrupt handling). On chipsets where this
105241b9eb26SStefan Assmann	  boot IRQ generation cannot be disabled, this workaround keeps
105341b9eb26SStefan Assmann	  the original IRQ line masked so that only the equivalent "boot
105441b9eb26SStefan Assmann	  IRQ" is delivered to the CPUs. The workaround also tells the
105541b9eb26SStefan Assmann	  kernel to set up the IRQ handler on the boot IRQ line. In this
105641b9eb26SStefan Assmann	  way only one interrupt is delivered to the kernel. Otherwise
105741b9eb26SStefan Assmann	  the spurious second interrupt may cause the kernel to bring
105841b9eb26SStefan Assmann	  down (vital) interrupt lines.
105941b9eb26SStefan Assmann
106041b9eb26SStefan Assmann	  Only affects "broken" chipsets. Interrupt sharing may be
106141b9eb26SStefan Assmann	  increased on these systems.
106241b9eb26SStefan Assmann
1063506f1d07SSam Ravnborgconfig X86_MCE
1064bab9bc65SAndi Kleen	bool "Machine Check / overheating reporting"
1065648ed940SChen, Gong	select GENERIC_ALLOCATOR
1066e57dbaf7SBorislav Petkov	default y
1067506f1d07SSam Ravnborg	---help---
1068bab9bc65SAndi Kleen	  Machine Check support allows the processor to notify the
1069bab9bc65SAndi Kleen	  kernel if it detects a problem (e.g. overheating, data corruption).
1070506f1d07SSam Ravnborg	  The action the kernel takes depends on the severity of the problem,
1071bab9bc65SAndi Kleen	  ranging from warning messages to halting the machine.
10724efc0670SAndi Kleen
10735de97c9fSTony Luckconfig X86_MCELOG_LEGACY
10745de97c9fSTony Luck	bool "Support for deprecated /dev/mcelog character device"
10755de97c9fSTony Luck	depends on X86_MCE
10765de97c9fSTony Luck	---help---
10775de97c9fSTony Luck	  Enable support for /dev/mcelog which is needed by the old mcelog
10785de97c9fSTony Luck	  userspace logging daemon. Consider switching to the new generation
10795de97c9fSTony Luck	  rasdaemon solution.
10805de97c9fSTony Luck
1081506f1d07SSam Ravnborgconfig X86_MCE_INTEL
10823c2362e6SHarvey Harrison	def_bool y
10833c2362e6SHarvey Harrison	prompt "Intel MCE features"
1084c1ebf835SAndi Kleen	depends on X86_MCE && X86_LOCAL_APIC
10858f9ca475SIngo Molnar	---help---
1086506f1d07SSam Ravnborg	   Additional support for intel specific MCE features such as
1087506f1d07SSam Ravnborg	   the thermal monitor.
1088506f1d07SSam Ravnborg
1089506f1d07SSam Ravnborgconfig X86_MCE_AMD
10903c2362e6SHarvey Harrison	def_bool y
10913c2362e6SHarvey Harrison	prompt "AMD MCE features"
1092f5382de9SYazen Ghannam	depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
10938f9ca475SIngo Molnar	---help---
1094506f1d07SSam Ravnborg	   Additional support for AMD specific MCE features such as
1095506f1d07SSam Ravnborg	   the DRAM Error Threshold.
1096506f1d07SSam Ravnborg
10974efc0670SAndi Kleenconfig X86_ANCIENT_MCE
10986fc108a0SJan Beulich	bool "Support for old Pentium 5 / WinChip machine checks"
1099c31d9633SAndi Kleen	depends on X86_32 && X86_MCE
11004efc0670SAndi Kleen	---help---
11014efc0670SAndi Kleen	  Include support for machine check handling on old Pentium 5 or WinChip
11025065a706SMasanari Iida	  systems. These typically need to be enabled explicitly on the command
11034efc0670SAndi Kleen	  line.
11044efc0670SAndi Kleen
1105b2762686SAndi Kleenconfig X86_MCE_THRESHOLD
1106b2762686SAndi Kleen	depends on X86_MCE_AMD || X86_MCE_INTEL
11076fc108a0SJan Beulich	def_bool y
1108b2762686SAndi Kleen
1109ea149b36SAndi Kleenconfig X86_MCE_INJECT
1110bc8e80d5SBorislav Petkov	depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
1111ea149b36SAndi Kleen	tristate "Machine check injector support"
1112ea149b36SAndi Kleen	---help---
1113ea149b36SAndi Kleen	  Provide support for injecting machine checks for testing purposes.
1114ea149b36SAndi Kleen	  If you don't know what a machine check is and you don't do kernel
1115ea149b36SAndi Kleen	  QA it is safe to say n.
1116ea149b36SAndi Kleen
11174efc0670SAndi Kleenconfig X86_THERMAL_VECTOR
11184efc0670SAndi Kleen	def_bool y
11195bb38adcSAndi Kleen	depends on X86_MCE_INTEL
11204efc0670SAndi Kleen
112107dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig"
1122e633c65aSKan Liang
11235aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86
11241e642812SIngo Molnar	bool "Legacy VM86 support"
11255aef51c3SAndy Lutomirski	default n
1126506f1d07SSam Ravnborg	depends on X86_32
11278f9ca475SIngo Molnar	---help---
11285aef51c3SAndy Lutomirski	  This option allows user programs to put the CPU into V8086
11295aef51c3SAndy Lutomirski	  mode, which is an 80286-era approximation of 16-bit real mode.
11305aef51c3SAndy Lutomirski
11315aef51c3SAndy Lutomirski	  Some very old versions of X and/or vbetool require this option
11325aef51c3SAndy Lutomirski	  for user mode setting.  Similarly, DOSEMU will use it if
11335aef51c3SAndy Lutomirski	  available to accelerate real mode DOS programs.  However, any
11345aef51c3SAndy Lutomirski	  recent version of DOSEMU, X, or vbetool should be fully
11355aef51c3SAndy Lutomirski	  functional even without kernel VM86 support, as they will all
11361e642812SIngo Molnar	  fall back to software emulation. Nevertheless, if you are using
11371e642812SIngo Molnar	  a 16-bit DOS program where 16-bit performance matters, vm86
11381e642812SIngo Molnar	  mode might be faster than emulation and you might want to
11391e642812SIngo Molnar	  enable this option.
11405aef51c3SAndy Lutomirski
11411e642812SIngo Molnar	  Note that any app that works on a 64-bit kernel is unlikely to
11421e642812SIngo Molnar	  need this option, as 64-bit kernels don't, and can't, support
11431e642812SIngo Molnar	  V8086 mode. This option is also unrelated to 16-bit protected
11441e642812SIngo Molnar	  mode and is not needed to run most 16-bit programs under Wine.
11455aef51c3SAndy Lutomirski
11461e642812SIngo Molnar	  Enabling this option increases the complexity of the kernel
11471e642812SIngo Molnar	  and slows down exception handling a tiny bit.
11485aef51c3SAndy Lutomirski
11491e642812SIngo Molnar	  If unsure, say N here.
11505aef51c3SAndy Lutomirski
11515aef51c3SAndy Lutomirskiconfig VM86
11525aef51c3SAndy Lutomirski       bool
11535aef51c3SAndy Lutomirski       default X86_LEGACY_VM86
115434273f41SH. Peter Anvin
115534273f41SH. Peter Anvinconfig X86_16BIT
115634273f41SH. Peter Anvin	bool "Enable support for 16-bit segments" if EXPERT
115734273f41SH. Peter Anvin	default y
1158a5b9e5a2SAndy Lutomirski	depends on MODIFY_LDT_SYSCALL
115934273f41SH. Peter Anvin	---help---
116034273f41SH. Peter Anvin	  This option is required by programs like Wine to run 16-bit
116134273f41SH. Peter Anvin	  protected mode legacy code on x86 processors.  Disabling
116234273f41SH. Peter Anvin	  this option saves about 300 bytes on i386, or around 6K text
116334273f41SH. Peter Anvin	  plus 16K runtime memory on x86-64,
116434273f41SH. Peter Anvin
116534273f41SH. Peter Anvinconfig X86_ESPFIX32
116634273f41SH. Peter Anvin	def_bool y
116734273f41SH. Peter Anvin	depends on X86_16BIT && X86_32
1168506f1d07SSam Ravnborg
1169197725deSH. Peter Anvinconfig X86_ESPFIX64
1170197725deSH. Peter Anvin	def_bool y
117134273f41SH. Peter Anvin	depends on X86_16BIT && X86_64
1172506f1d07SSam Ravnborg
11731ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION
11741ad83c85SAndy Lutomirski       bool "Enable vsyscall emulation" if EXPERT
11751ad83c85SAndy Lutomirski       default y
11761ad83c85SAndy Lutomirski       depends on X86_64
11771ad83c85SAndy Lutomirski       ---help---
11781ad83c85SAndy Lutomirski	 This enables emulation of the legacy vsyscall page.  Disabling
11791ad83c85SAndy Lutomirski	 it is roughly equivalent to booting with vsyscall=none, except
11801ad83c85SAndy Lutomirski	 that it will also disable the helpful warning if a program
11811ad83c85SAndy Lutomirski	 tries to use a vsyscall.  With this option set to N, offending
11821ad83c85SAndy Lutomirski	 programs will just segfault, citing addresses of the form
11831ad83c85SAndy Lutomirski	 0xffffffffff600?00.
11841ad83c85SAndy Lutomirski
11851ad83c85SAndy Lutomirski	 This option is required by many programs built before 2013, and
11861ad83c85SAndy Lutomirski	 care should be used even with newer programs if set to N.
11871ad83c85SAndy Lutomirski
11881ad83c85SAndy Lutomirski	 Disabling this option saves about 7K of kernel size and
11891ad83c85SAndy Lutomirski	 possibly 4K of additional runtime pagetable memory.
11901ad83c85SAndy Lutomirski
1191506f1d07SSam Ravnborgconfig TOSHIBA
1192506f1d07SSam Ravnborg	tristate "Toshiba Laptop support"
1193506f1d07SSam Ravnborg	depends on X86_32
1194506f1d07SSam Ravnborg	---help---
1195506f1d07SSam Ravnborg	  This adds a driver to safely access the System Management Mode of
1196506f1d07SSam Ravnborg	  the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1197506f1d07SSam Ravnborg	  not work on models with a Phoenix BIOS. The System Management Mode
1198506f1d07SSam Ravnborg	  is used to set the BIOS and power saving options on Toshiba portables.
1199506f1d07SSam Ravnborg
1200506f1d07SSam Ravnborg	  For information on utilities to make use of this driver see the
1201506f1d07SSam Ravnborg	  Toshiba Linux utilities web site at:
1202506f1d07SSam Ravnborg	  <http://www.buzzard.org.uk/toshiba/>.
1203506f1d07SSam Ravnborg
1204506f1d07SSam Ravnborg	  Say Y if you intend to run this kernel on a Toshiba portable.
1205506f1d07SSam Ravnborg	  Say N otherwise.
1206506f1d07SSam Ravnborg
1207506f1d07SSam Ravnborgconfig I8K
1208039ae585SPali Rohár	tristate "Dell i8k legacy laptop support"
1209949a9d70SJean Delvare	select HWMON
1210039ae585SPali Rohár	select SENSORS_DELL_SMM
1211506f1d07SSam Ravnborg	---help---
1212039ae585SPali Rohár	  This option enables legacy /proc/i8k userspace interface in hwmon
1213039ae585SPali Rohár	  dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1214039ae585SPali Rohár	  temperature and allows controlling fan speeds of Dell laptops via
1215039ae585SPali Rohár	  System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1216039ae585SPali Rohár	  it reports also power and hotkey status. For fan speed control is
1217039ae585SPali Rohár	  needed userspace package i8kutils.
1218506f1d07SSam Ravnborg
1219039ae585SPali Rohár	  Say Y if you intend to run this kernel on old Dell laptops or want to
1220039ae585SPali Rohár	  use userspace package i8kutils.
1221506f1d07SSam Ravnborg	  Say N otherwise.
1222506f1d07SSam Ravnborg
1223506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS
12249ba16087SJan Beulich	bool "Enable X86 board specific fixups for reboot"
12259ba16087SJan Beulich	depends on X86_32
1226506f1d07SSam Ravnborg	---help---
1227506f1d07SSam Ravnborg	  This enables chipset and/or board specific fixups to be done
1228506f1d07SSam Ravnborg	  in order to get reboot to work correctly. This is only needed on
1229506f1d07SSam Ravnborg	  some combinations of hardware and BIOS. The symptom, for which
1230506f1d07SSam Ravnborg	  this config is intended, is when reboot ends with a stalled/hung
1231506f1d07SSam Ravnborg	  system.
1232506f1d07SSam Ravnborg
1233506f1d07SSam Ravnborg	  Currently, the only fixup is for the Geode machines using
12345e3a77e9SFlorian Fainelli	  CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1235506f1d07SSam Ravnborg
1236506f1d07SSam Ravnborg	  Say Y if you want to enable the fixup. Currently, it's safe to
1237506f1d07SSam Ravnborg	  enable this option even if you don't need it.
1238506f1d07SSam Ravnborg	  Say N otherwise.
1239506f1d07SSam Ravnborg
1240506f1d07SSam Ravnborgconfig MICROCODE
12419a2bc335SBorislav Petkov	bool "CPU microcode loading support"
12429a2bc335SBorislav Petkov	default y
124380030e3dSBorislav Petkov	depends on CPU_SUP_AMD || CPU_SUP_INTEL
1244506f1d07SSam Ravnborg	select FW_LOADER
1245506f1d07SSam Ravnborg	---help---
1246506f1d07SSam Ravnborg	  If you say Y here, you will be able to update the microcode on
12475f9c01aaSBorislav Petkov	  Intel and AMD processors. The Intel support is for the IA32 family,
12485f9c01aaSBorislav Petkov	  e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
12495f9c01aaSBorislav Petkov	  AMD support is for families 0x10 and later. You will obviously need
12505f9c01aaSBorislav Petkov	  the actual microcode binary data itself which is not shipped with
12515f9c01aaSBorislav Petkov	  the Linux kernel.
1252506f1d07SSam Ravnborg
12535f9c01aaSBorislav Petkov	  The preferred method to load microcode from a detached initrd is described
12545f9c01aaSBorislav Petkov	  in Documentation/x86/early-microcode.txt. For that you need to enable
12555f9c01aaSBorislav Petkov	  CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
12565f9c01aaSBorislav Petkov	  initrd for microcode blobs.
1257506f1d07SSam Ravnborg
12585f9c01aaSBorislav Petkov	  In addition, you can build-in the microcode into the kernel. For that you
12595f9c01aaSBorislav Petkov	  need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode
12605f9c01aaSBorislav Petkov	  to the CONFIG_EXTRA_FIRMWARE config option.
1261506f1d07SSam Ravnborg
12628d86f390SPeter Orubaconfig MICROCODE_INTEL
1263e43f6e67SBorislav Petkov	bool "Intel microcode loading support"
12648d86f390SPeter Oruba	depends on MICROCODE
12658d86f390SPeter Oruba	default MICROCODE
12668d86f390SPeter Oruba	select FW_LOADER
12678f9ca475SIngo Molnar	---help---
12688d86f390SPeter Oruba	  This options enables microcode patch loading support for Intel
12698d86f390SPeter Oruba	  processors.
12708d86f390SPeter Oruba
1271b8989db9SAlan	  For the current Intel microcode data package go to
1272b8989db9SAlan	  <https://downloadcenter.intel.com> and search for
1273b8989db9SAlan	  'Linux Processor Microcode Data File'.
12748d86f390SPeter Oruba
127580cc9f10SPeter Orubaconfig MICROCODE_AMD
1276e43f6e67SBorislav Petkov	bool "AMD microcode loading support"
127780cc9f10SPeter Oruba	depends on MICROCODE
127880cc9f10SPeter Oruba	select FW_LOADER
12798f9ca475SIngo Molnar	---help---
128080cc9f10SPeter Oruba	  If you select this option, microcode patch loading support for AMD
128180cc9f10SPeter Oruba	  processors will be enabled.
128280cc9f10SPeter Oruba
1283506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE
12843c2362e6SHarvey Harrison	def_bool y
1285506f1d07SSam Ravnborg	depends on MICROCODE
1286506f1d07SSam Ravnborg
1287506f1d07SSam Ravnborgconfig X86_MSR
1288506f1d07SSam Ravnborg	tristate "/dev/cpu/*/msr - Model-specific register support"
12898f9ca475SIngo Molnar	---help---
1290506f1d07SSam Ravnborg	  This device gives privileged processes access to the x86
1291506f1d07SSam Ravnborg	  Model-Specific Registers (MSRs).  It is a character device with
1292506f1d07SSam Ravnborg	  major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1293506f1d07SSam Ravnborg	  MSR accesses are directed to a specific CPU on multi-processor
1294506f1d07SSam Ravnborg	  systems.
1295506f1d07SSam Ravnborg
1296506f1d07SSam Ravnborgconfig X86_CPUID
1297506f1d07SSam Ravnborg	tristate "/dev/cpu/*/cpuid - CPU information support"
12988f9ca475SIngo Molnar	---help---
1299506f1d07SSam Ravnborg	  This device gives processes access to the x86 CPUID instruction to
1300506f1d07SSam Ravnborg	  be executed on a specific processor.  It is a character device
1301506f1d07SSam Ravnborg	  with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1302506f1d07SSam Ravnborg	  /dev/cpu/31/cpuid.
1303506f1d07SSam Ravnborg
1304506f1d07SSam Ravnborgchoice
1305506f1d07SSam Ravnborg	prompt "High Memory Support"
13066fc108a0SJan Beulich	default HIGHMEM4G
1307506f1d07SSam Ravnborg	depends on X86_32
1308506f1d07SSam Ravnborg
1309506f1d07SSam Ravnborgconfig NOHIGHMEM
1310506f1d07SSam Ravnborg	bool "off"
1311506f1d07SSam Ravnborg	---help---
1312506f1d07SSam Ravnborg	  Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1313506f1d07SSam Ravnborg	  However, the address space of 32-bit x86 processors is only 4
1314506f1d07SSam Ravnborg	  Gigabytes large. That means that, if you have a large amount of
1315506f1d07SSam Ravnborg	  physical memory, not all of it can be "permanently mapped" by the
1316506f1d07SSam Ravnborg	  kernel. The physical memory that's not permanently mapped is called
1317506f1d07SSam Ravnborg	  "high memory".
1318506f1d07SSam Ravnborg
1319506f1d07SSam Ravnborg	  If you are compiling a kernel which will never run on a machine with
1320506f1d07SSam Ravnborg	  more than 1 Gigabyte total physical RAM, answer "off" here (default
1321506f1d07SSam Ravnborg	  choice and suitable for most users). This will result in a "3GB/1GB"
1322506f1d07SSam Ravnborg	  split: 3GB are mapped so that each process sees a 3GB virtual memory
1323506f1d07SSam Ravnborg	  space and the remaining part of the 4GB virtual memory space is used
1324506f1d07SSam Ravnborg	  by the kernel to permanently map as much physical memory as
1325506f1d07SSam Ravnborg	  possible.
1326506f1d07SSam Ravnborg
1327506f1d07SSam Ravnborg	  If the machine has between 1 and 4 Gigabytes physical RAM, then
1328506f1d07SSam Ravnborg	  answer "4GB" here.
1329506f1d07SSam Ravnborg
1330506f1d07SSam Ravnborg	  If more than 4 Gigabytes is used then answer "64GB" here. This
1331506f1d07SSam Ravnborg	  selection turns Intel PAE (Physical Address Extension) mode on.
1332506f1d07SSam Ravnborg	  PAE implements 3-level paging on IA32 processors. PAE is fully
1333506f1d07SSam Ravnborg	  supported by Linux, PAE mode is implemented on all recent Intel
1334506f1d07SSam Ravnborg	  processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1335506f1d07SSam Ravnborg	  then the kernel will not boot on CPUs that don't support PAE!
1336506f1d07SSam Ravnborg
1337506f1d07SSam Ravnborg	  The actual amount of total physical memory will either be
1338506f1d07SSam Ravnborg	  auto detected or can be forced by using a kernel command line option
1339506f1d07SSam Ravnborg	  such as "mem=256M". (Try "man bootparam" or see the documentation of
1340506f1d07SSam Ravnborg	  your boot loader (lilo or loadlin) about how to pass options to the
1341506f1d07SSam Ravnborg	  kernel at boot time.)
1342506f1d07SSam Ravnborg
1343506f1d07SSam Ravnborg	  If unsure, say "off".
1344506f1d07SSam Ravnborg
1345506f1d07SSam Ravnborgconfig HIGHMEM4G
1346506f1d07SSam Ravnborg	bool "4GB"
13478f9ca475SIngo Molnar	---help---
1348506f1d07SSam Ravnborg	  Select this if you have a 32-bit processor and between 1 and 4
1349506f1d07SSam Ravnborg	  gigabytes of physical RAM.
1350506f1d07SSam Ravnborg
1351506f1d07SSam Ravnborgconfig HIGHMEM64G
1352506f1d07SSam Ravnborg	bool "64GB"
1353eb068e78SH. Peter Anvin	depends on !M486
1354506f1d07SSam Ravnborg	select X86_PAE
13558f9ca475SIngo Molnar	---help---
1356506f1d07SSam Ravnborg	  Select this if you have a 32-bit processor and more than 4
1357506f1d07SSam Ravnborg	  gigabytes of physical RAM.
1358506f1d07SSam Ravnborg
1359506f1d07SSam Ravnborgendchoice
1360506f1d07SSam Ravnborg
1361506f1d07SSam Ravnborgchoice
13626a108a14SDavid Rientjes	prompt "Memory split" if EXPERT
1363506f1d07SSam Ravnborg	default VMSPLIT_3G
1364506f1d07SSam Ravnborg	depends on X86_32
13658f9ca475SIngo Molnar	---help---
1366506f1d07SSam Ravnborg	  Select the desired split between kernel and user memory.
1367506f1d07SSam Ravnborg
1368506f1d07SSam Ravnborg	  If the address range available to the kernel is less than the
1369506f1d07SSam Ravnborg	  physical memory installed, the remaining memory will be available
1370506f1d07SSam Ravnborg	  as "high memory". Accessing high memory is a little more costly
1371506f1d07SSam Ravnborg	  than low memory, as it needs to be mapped into the kernel first.
1372506f1d07SSam Ravnborg	  Note that increasing the kernel address space limits the range
1373506f1d07SSam Ravnborg	  available to user programs, making the address space there
1374506f1d07SSam Ravnborg	  tighter.  Selecting anything other than the default 3G/1G split
1375506f1d07SSam Ravnborg	  will also likely make your kernel incompatible with binary-only
1376506f1d07SSam Ravnborg	  kernel modules.
1377506f1d07SSam Ravnborg
1378506f1d07SSam Ravnborg	  If you are not absolutely sure what you are doing, leave this
1379506f1d07SSam Ravnborg	  option alone!
1380506f1d07SSam Ravnborg
1381506f1d07SSam Ravnborg	config VMSPLIT_3G
1382506f1d07SSam Ravnborg		bool "3G/1G user/kernel split"
1383506f1d07SSam Ravnborg	config VMSPLIT_3G_OPT
1384506f1d07SSam Ravnborg		depends on !X86_PAE
1385506f1d07SSam Ravnborg		bool "3G/1G user/kernel split (for full 1G low memory)"
1386506f1d07SSam Ravnborg	config VMSPLIT_2G
1387506f1d07SSam Ravnborg		bool "2G/2G user/kernel split"
1388506f1d07SSam Ravnborg	config VMSPLIT_2G_OPT
1389506f1d07SSam Ravnborg		depends on !X86_PAE
1390506f1d07SSam Ravnborg		bool "2G/2G user/kernel split (for full 2G low memory)"
1391506f1d07SSam Ravnborg	config VMSPLIT_1G
1392506f1d07SSam Ravnborg		bool "1G/3G user/kernel split"
1393506f1d07SSam Ravnborgendchoice
1394506f1d07SSam Ravnborg
1395506f1d07SSam Ravnborgconfig PAGE_OFFSET
1396506f1d07SSam Ravnborg	hex
1397506f1d07SSam Ravnborg	default 0xB0000000 if VMSPLIT_3G_OPT
1398506f1d07SSam Ravnborg	default 0x80000000 if VMSPLIT_2G
1399506f1d07SSam Ravnborg	default 0x78000000 if VMSPLIT_2G_OPT
1400506f1d07SSam Ravnborg	default 0x40000000 if VMSPLIT_1G
1401506f1d07SSam Ravnborg	default 0xC0000000
1402506f1d07SSam Ravnborg	depends on X86_32
1403506f1d07SSam Ravnborg
1404506f1d07SSam Ravnborgconfig HIGHMEM
14053c2362e6SHarvey Harrison	def_bool y
1406506f1d07SSam Ravnborg	depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1407506f1d07SSam Ravnborg
1408506f1d07SSam Ravnborgconfig X86_PAE
14099ba16087SJan Beulich	bool "PAE (Physical Address Extension) Support"
1410506f1d07SSam Ravnborg	depends on X86_32 && !HIGHMEM4G
14119d99c712SChristian Melki	select SWIOTLB
14128f9ca475SIngo Molnar	---help---
1413506f1d07SSam Ravnborg	  PAE is required for NX support, and furthermore enables
1414506f1d07SSam Ravnborg	  larger swapspace support for non-overcommit purposes. It
1415506f1d07SSam Ravnborg	  has the cost of more pagetable lookup overhead, and also
1416506f1d07SSam Ravnborg	  consumes more pagetable space per process.
1417506f1d07SSam Ravnborg
141877ef56e4SKirill A. Shutemovconfig X86_5LEVEL
141977ef56e4SKirill A. Shutemov	bool "Enable 5-level page tables support"
142077ef56e4SKirill A. Shutemov	depends on X86_64
142177ef56e4SKirill A. Shutemov	---help---
142277ef56e4SKirill A. Shutemov	  5-level paging enables access to larger address space:
142377ef56e4SKirill A. Shutemov	  upto 128 PiB of virtual address space and 4 PiB of
142477ef56e4SKirill A. Shutemov	  physical address space.
142577ef56e4SKirill A. Shutemov
142677ef56e4SKirill A. Shutemov	  It will be supported by future Intel CPUs.
142777ef56e4SKirill A. Shutemov
142877ef56e4SKirill A. Shutemov	  Note: a kernel with this option enabled can only be booted
142977ef56e4SKirill A. Shutemov	  on machines that support the feature.
143077ef56e4SKirill A. Shutemov
143177ef56e4SKirill A. Shutemov	  See Documentation/x86/x86_64/5level-paging.txt for more
143277ef56e4SKirill A. Shutemov	  information.
143377ef56e4SKirill A. Shutemov
143477ef56e4SKirill A. Shutemov	  Say N if unsure.
143577ef56e4SKirill A. Shutemov
1436600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT
14373120e25eSJan Beulich	def_bool y
14383120e25eSJan Beulich	depends on X86_64 || X86_PAE
1439600715dcSJeremy Fitzhardinge
144066f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT
14413120e25eSJan Beulich	def_bool y
14423120e25eSJan Beulich	depends on X86_64 || HIGHMEM64G
144366f2b061SFUJITA Tomonori
144410971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES
1445e5008abeSLuis R. Rodriguez	def_bool y
1446e5008abeSLuis R. Rodriguez	depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
14478f9ca475SIngo Molnar	---help---
144810971ab2SIngo Molnar	  Certain kernel features effectively disable kernel
144910971ab2SIngo Molnar	  linear 1 GB mappings (even if the CPU otherwise
145010971ab2SIngo Molnar	  supports them), so don't confuse the user by printing
145110971ab2SIngo Molnar	  that we have them enabled.
14529e899816SNick Piggin
14537744ccdbSTom Lendackyconfig ARCH_HAS_MEM_ENCRYPT
14547744ccdbSTom Lendacky	def_bool y
14557744ccdbSTom Lendacky
14567744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT
14577744ccdbSTom Lendacky	bool "AMD Secure Memory Encryption (SME) support"
14587744ccdbSTom Lendacky	depends on X86_64 && CPU_SUP_AMD
14597744ccdbSTom Lendacky	---help---
14607744ccdbSTom Lendacky	  Say yes to enable support for the encryption of system memory.
14617744ccdbSTom Lendacky	  This requires an AMD processor that supports Secure Memory
14627744ccdbSTom Lendacky	  Encryption (SME).
14637744ccdbSTom Lendacky
14647744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
14657744ccdbSTom Lendacky	bool "Activate AMD Secure Memory Encryption (SME) by default"
14667744ccdbSTom Lendacky	default y
14677744ccdbSTom Lendacky	depends on AMD_MEM_ENCRYPT
14687744ccdbSTom Lendacky	---help---
14697744ccdbSTom Lendacky	  Say yes to have system memory encrypted by default if running on
14707744ccdbSTom Lendacky	  an AMD processor that supports Secure Memory Encryption (SME).
14717744ccdbSTom Lendacky
14727744ccdbSTom Lendacky	  If set to Y, then the encryption of system memory can be
14737744ccdbSTom Lendacky	  deactivated with the mem_encrypt=off command line option.
14747744ccdbSTom Lendacky
14757744ccdbSTom Lendacky	  If set to N, then the encryption of system memory can be
14767744ccdbSTom Lendacky	  activated with the mem_encrypt=on command line option.
14777744ccdbSTom Lendacky
1478f88a68faSTom Lendackyconfig ARCH_USE_MEMREMAP_PROT
1479f88a68faSTom Lendacky	def_bool y
1480f88a68faSTom Lendacky	depends on AMD_MEM_ENCRYPT
1481f88a68faSTom Lendacky
1482506f1d07SSam Ravnborg# Common NUMA Features
1483506f1d07SSam Ravnborgconfig NUMA
1484fd51b2d7SKOSAKI Motohiro	bool "Numa Memory Allocation and Scheduler Support"
1485506f1d07SSam Ravnborg	depends on SMP
1486b5660ba7SH. Peter Anvin	depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1487b5660ba7SH. Peter Anvin	default y if X86_BIGSMP
14888f9ca475SIngo Molnar	---help---
1489506f1d07SSam Ravnborg	  Enable NUMA (Non Uniform Memory Access) support.
1490fd51b2d7SKOSAKI Motohiro
1491506f1d07SSam Ravnborg	  The kernel will try to allocate memory used by a CPU on the
1492506f1d07SSam Ravnborg	  local memory controller of the CPU and add some more
1493506f1d07SSam Ravnborg	  NUMA awareness to the kernel.
1494506f1d07SSam Ravnborg
1495c280ea5eSIngo Molnar	  For 64-bit this is recommended if the system is Intel Core i7
1496fd51b2d7SKOSAKI Motohiro	  (or later), AMD Opteron, or EM64T NUMA.
1497fd51b2d7SKOSAKI Motohiro
1498b5660ba7SH. Peter Anvin	  For 32-bit this is only needed if you boot a 32-bit
14997cf6c945SDavid Rientjes	  kernel on a 64-bit NUMA platform.
1500fd51b2d7SKOSAKI Motohiro
1501fd51b2d7SKOSAKI Motohiro	  Otherwise, you should say N.
1502506f1d07SSam Ravnborg
1503eec1d4faSHans Rosenfeldconfig AMD_NUMA
15043c2362e6SHarvey Harrison	def_bool y
15053c2362e6SHarvey Harrison	prompt "Old style AMD Opteron NUMA detection"
15065da0ef9aSTejun Heo	depends on X86_64 && NUMA && PCI
15078f9ca475SIngo Molnar	---help---
1508eec1d4faSHans Rosenfeld	  Enable AMD NUMA node topology detection.  You should say Y here if
1509eec1d4faSHans Rosenfeld	  you have a multi processor AMD system. This uses an old method to
1510eec1d4faSHans Rosenfeld	  read the NUMA configuration directly from the builtin Northbridge
1511eec1d4faSHans Rosenfeld	  of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1512eec1d4faSHans Rosenfeld	  which also takes priority if both are compiled in.
1513506f1d07SSam Ravnborg
1514506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA
15153c2362e6SHarvey Harrison	def_bool y
15163c2362e6SHarvey Harrison	prompt "ACPI NUMA detection"
1517506f1d07SSam Ravnborg	depends on X86_64 && NUMA && ACPI && PCI
1518506f1d07SSam Ravnborg	select ACPI_NUMA
15198f9ca475SIngo Molnar	---help---
1520506f1d07SSam Ravnborg	  Enable ACPI SRAT based node topology detection.
1521506f1d07SSam Ravnborg
15226ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span
15236ec6e0d9SSuresh Siddha# other nodes.  Even though a pfn is valid and
15246ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not
15256ec6e0d9SSuresh Siddha# reside on that node.  See memmap_init_zone()
15266ec6e0d9SSuresh Siddha# for details.
15276ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES
15286ec6e0d9SSuresh Siddha	def_bool y
15296ec6e0d9SSuresh Siddha	depends on X86_64_ACPI_NUMA
15306ec6e0d9SSuresh Siddha
1531506f1d07SSam Ravnborgconfig NUMA_EMU
1532506f1d07SSam Ravnborg	bool "NUMA emulation"
15331b7e03efSTejun Heo	depends on NUMA
15348f9ca475SIngo Molnar	---help---
1535506f1d07SSam Ravnborg	  Enable NUMA emulation. A flat machine will be split
1536506f1d07SSam Ravnborg	  into virtual nodes when booted with "numa=fake=N", where N is the
1537506f1d07SSam Ravnborg	  number of nodes. This is only useful for debugging.
1538506f1d07SSam Ravnborg
1539506f1d07SSam Ravnborgconfig NODES_SHIFT
1540d25e26b6SLinus Torvalds	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
154151591e31SDavid Rientjes	range 1 10
154251591e31SDavid Rientjes	default "10" if MAXSMP
1543506f1d07SSam Ravnborg	default "6" if X86_64
1544506f1d07SSam Ravnborg	default "3"
1545506f1d07SSam Ravnborg	depends on NEED_MULTIPLE_NODES
15468f9ca475SIngo Molnar	---help---
15471184dc2fSMike Travis	  Specify the maximum number of NUMA Nodes available on the target
1548692105b8SMatt LaPlante	  system.  Increases memory reserved to accommodate various tables.
1549506f1d07SSam Ravnborg
1550506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT
15513c2362e6SHarvey Harrison	def_bool y
1552506f1d07SSam Ravnborg	depends on X86_32 && DISCONTIGMEM
1553506f1d07SSam Ravnborg
1554506f1d07SSam Ravnborgconfig NEED_NODE_MEMMAP_SIZE
15553c2362e6SHarvey Harrison	def_bool y
1556506f1d07SSam Ravnborg	depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1557506f1d07SSam Ravnborg
1558506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE
1559506f1d07SSam Ravnborg	def_bool y
15603b16651fSTejun Heo	depends on X86_32 && !NUMA
1561506f1d07SSam Ravnborg
1562506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE
1563506f1d07SSam Ravnborg	def_bool y
1564b263295dSChristoph Lameter	depends on NUMA && X86_32
1565506f1d07SSam Ravnborg
1566506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT
1567506f1d07SSam Ravnborg	def_bool y
1568b263295dSChristoph Lameter	depends on NUMA && X86_32
1569b263295dSChristoph Lameter
1570506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE
1571506f1d07SSam Ravnborg	def_bool y
15726ea30386SKees Cook	depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1573506f1d07SSam Ravnborg	select SPARSEMEM_STATIC if X86_32
1574506f1d07SSam Ravnborg	select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1575506f1d07SSam Ravnborg
15763b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT
15773b16651fSTejun Heo	def_bool y
15783b16651fSTejun Heo	depends on X86_64
15793b16651fSTejun Heo
1580506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL
1581506f1d07SSam Ravnborg	def_bool y
1582b263295dSChristoph Lameter	depends on ARCH_SPARSEMEM_ENABLE
1583506f1d07SSam Ravnborg
1584506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE
1585a0842b70SToshi Kani	bool "Enable sysfs memory/probe interface"
15863120e25eSJan Beulich	depends on X86_64 && MEMORY_HOTPLUG
1587a0842b70SToshi Kani	help
1588a0842b70SToshi Kani	  This option enables a sysfs memory/probe interface for testing.
1589a0842b70SToshi Kani	  See Documentation/memory-hotplug.txt for more information.
1590a0842b70SToshi Kani	  If you are unsure how to answer this question, answer N.
1591506f1d07SSam Ravnborg
15923b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT
15933b16651fSTejun Heo	def_bool y
15943b16651fSTejun Heo	depends on X86_64 && PROC_KCORE
15953b16651fSTejun Heo
1596a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE
1597a29815a3SAvi Kivity       hex
1598a29815a3SAvi Kivity       default 0 if X86_32
1599a29815a3SAvi Kivity       default 0xdead000000000000 if X86_64
1600a29815a3SAvi Kivity
1601506f1d07SSam Ravnborgsource "mm/Kconfig"
1602506f1d07SSam Ravnborg
16037a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE
16047a67832cSDan Williams	bool
16057a67832cSDan Williams
1606ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY
16077a67832cSDan Williams	tristate "Support non-standard NVDIMMs and ADR protected memory"
16089f53f9faSDan Williams	depends on PHYS_ADDR_T_64BIT
16099f53f9faSDan Williams	depends on BLK_DEV
16107a67832cSDan Williams	select X86_PMEM_LEGACY_DEVICE
16119f53f9faSDan Williams	select LIBNVDIMM
1612ec776ef6SChristoph Hellwig	help
1613ec776ef6SChristoph Hellwig	  Treat memory marked using the non-standard e820 type of 12 as used
1614ec776ef6SChristoph Hellwig	  by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1615ec776ef6SChristoph Hellwig	  The kernel will offer these regions to the 'pmem' driver so
1616ec776ef6SChristoph Hellwig	  they can be used for persistent storage.
1617ec776ef6SChristoph Hellwig
1618ec776ef6SChristoph Hellwig	  Say Y if unsure.
1619ec776ef6SChristoph Hellwig
1620506f1d07SSam Ravnborgconfig HIGHPTE
1621506f1d07SSam Ravnborg	bool "Allocate 3rd-level pagetables from highmem"
16226fc108a0SJan Beulich	depends on HIGHMEM
16238f9ca475SIngo Molnar	---help---
1624506f1d07SSam Ravnborg	  The VM uses one page table entry for each page of physical memory.
1625506f1d07SSam Ravnborg	  For systems with a lot of RAM, this can be wasteful of precious
1626506f1d07SSam Ravnborg	  low memory.  Setting this option will put user-space page table
1627506f1d07SSam Ravnborg	  entries in high memory.
1628506f1d07SSam Ravnborg
16299f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION
16309f077871SJeremy Fitzhardinge	bool "Check for low memory corruption"
16318f9ca475SIngo Molnar	---help---
16329f077871SJeremy Fitzhardinge	  Periodically check for memory corruption in low memory, which
16339f077871SJeremy Fitzhardinge	  is suspected to be caused by BIOS.  Even when enabled in the
16349f077871SJeremy Fitzhardinge	  configuration, it is disabled at runtime.  Enable it by
16359f077871SJeremy Fitzhardinge	  setting "memory_corruption_check=1" on the kernel command
16369f077871SJeremy Fitzhardinge	  line.  By default it scans the low 64k of memory every 60
16379f077871SJeremy Fitzhardinge	  seconds; see the memory_corruption_check_size and
16389f077871SJeremy Fitzhardinge	  memory_corruption_check_period parameters in
16398c27ceffSMauro Carvalho Chehab	  Documentation/admin-guide/kernel-parameters.rst to adjust this.
16409f077871SJeremy Fitzhardinge
16419f077871SJeremy Fitzhardinge	  When enabled with the default parameters, this option has
16429f077871SJeremy Fitzhardinge	  almost no overhead, as it reserves a relatively small amount
16439f077871SJeremy Fitzhardinge	  of memory and scans it infrequently.  It both detects corruption
16449f077871SJeremy Fitzhardinge	  and prevents it from affecting the running system.
16459f077871SJeremy Fitzhardinge
16469f077871SJeremy Fitzhardinge	  It is, however, intended as a diagnostic tool; if repeatable
16479f077871SJeremy Fitzhardinge	  BIOS-originated corruption always affects the same memory,
16489f077871SJeremy Fitzhardinge	  you can use memmap= to prevent the kernel from using that
16499f077871SJeremy Fitzhardinge	  memory.
16509f077871SJeremy Fitzhardinge
1651c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1652c885df50SJeremy Fitzhardinge	bool "Set the default setting of memory_corruption_check"
1653c885df50SJeremy Fitzhardinge	depends on X86_CHECK_BIOS_CORRUPTION
1654c885df50SJeremy Fitzhardinge	default y
16558f9ca475SIngo Molnar	---help---
1656c885df50SJeremy Fitzhardinge	  Set whether the default state of memory_corruption_check is
1657c885df50SJeremy Fitzhardinge	  on or off.
1658c885df50SJeremy Fitzhardinge
16599ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW
1660d0cd7425SH. Peter Anvin	int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1661d0cd7425SH. Peter Anvin	default 64
1662d0cd7425SH. Peter Anvin	range 4 640
16638f9ca475SIngo Molnar	---help---
1664d0cd7425SH. Peter Anvin	  Specify the amount of low memory to reserve for the BIOS.
1665fc381519SIngo Molnar
1666d0cd7425SH. Peter Anvin	  The first page contains BIOS data structures that the kernel
1667d0cd7425SH. Peter Anvin	  must not use, so that page must always be reserved.
1668fc381519SIngo Molnar
1669d0cd7425SH. Peter Anvin	  By default we reserve the first 64K of physical RAM, as a
1670d0cd7425SH. Peter Anvin	  number of BIOSes are known to corrupt that memory range
1671d0cd7425SH. Peter Anvin	  during events such as suspend/resume or monitor cable
1672d0cd7425SH. Peter Anvin	  insertion, so it must not be used by the kernel.
1673fc381519SIngo Molnar
1674d0cd7425SH. Peter Anvin	  You can set this to 4 if you are absolutely sure that you
1675d0cd7425SH. Peter Anvin	  trust the BIOS to get all its memory reservations and usages
1676d0cd7425SH. Peter Anvin	  right.  If you know your BIOS have problems beyond the
1677d0cd7425SH. Peter Anvin	  default 64K area, you can set this to 640 to avoid using the
1678d0cd7425SH. Peter Anvin	  entire low memory range.
1679d0cd7425SH. Peter Anvin
1680d0cd7425SH. Peter Anvin	  If you have doubts about the BIOS (e.g. suspend/resume does
1681d0cd7425SH. Peter Anvin	  not work or there's kernel crashes after certain hardware
1682d0cd7425SH. Peter Anvin	  hotplug events) then you might want to enable
1683d0cd7425SH. Peter Anvin	  X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1684d0cd7425SH. Peter Anvin	  typical corruption patterns.
1685d0cd7425SH. Peter Anvin
1686d0cd7425SH. Peter Anvin	  Leave this to the default value of 64 if you are unsure.
1687fc381519SIngo Molnar
1688506f1d07SSam Ravnborgconfig MATH_EMULATION
1689506f1d07SSam Ravnborg	bool
1690a5b9e5a2SAndy Lutomirski	depends on MODIFY_LDT_SYSCALL
1691506f1d07SSam Ravnborg	prompt "Math emulation" if X86_32
1692506f1d07SSam Ravnborg	---help---
1693506f1d07SSam Ravnborg	  Linux can emulate a math coprocessor (used for floating point
1694506f1d07SSam Ravnborg	  operations) if you don't have one. 486DX and Pentium processors have
1695506f1d07SSam Ravnborg	  a math coprocessor built in, 486SX and 386 do not, unless you added
1696506f1d07SSam Ravnborg	  a 487DX or 387, respectively. (The messages during boot time can
1697506f1d07SSam Ravnborg	  give you some hints here ["man dmesg"].) Everyone needs either a
1698506f1d07SSam Ravnborg	  coprocessor or this emulation.
1699506f1d07SSam Ravnborg
1700506f1d07SSam Ravnborg	  If you don't have a math coprocessor, you need to say Y here; if you
1701506f1d07SSam Ravnborg	  say Y here even though you have a coprocessor, the coprocessor will
1702506f1d07SSam Ravnborg	  be used nevertheless. (This behavior can be changed with the kernel
1703506f1d07SSam Ravnborg	  command line option "no387", which comes handy if your coprocessor
1704506f1d07SSam Ravnborg	  is broken. Try "man bootparam" or see the documentation of your boot
1705506f1d07SSam Ravnborg	  loader (lilo or loadlin) about how to pass options to the kernel at
1706506f1d07SSam Ravnborg	  boot time.) This means that it is a good idea to say Y here if you
1707506f1d07SSam Ravnborg	  intend to use this kernel on different machines.
1708506f1d07SSam Ravnborg
1709506f1d07SSam Ravnborg	  More information about the internals of the Linux math coprocessor
1710506f1d07SSam Ravnborg	  emulation can be found in <file:arch/x86/math-emu/README>.
1711506f1d07SSam Ravnborg
1712506f1d07SSam Ravnborg	  If you are not sure, say Y; apart from resulting in a 66 KB bigger
1713506f1d07SSam Ravnborg	  kernel, it won't hurt.
1714506f1d07SSam Ravnborg
1715506f1d07SSam Ravnborgconfig MTRR
17166fc108a0SJan Beulich	def_bool y
17176a108a14SDavid Rientjes	prompt "MTRR (Memory Type Range Register) support" if EXPERT
1718506f1d07SSam Ravnborg	---help---
1719506f1d07SSam Ravnborg	  On Intel P6 family processors (Pentium Pro, Pentium II and later)
1720506f1d07SSam Ravnborg	  the Memory Type Range Registers (MTRRs) may be used to control
1721506f1d07SSam Ravnborg	  processor access to memory ranges. This is most useful if you have
1722506f1d07SSam Ravnborg	  a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1723506f1d07SSam Ravnborg	  allows bus write transfers to be combined into a larger transfer
1724506f1d07SSam Ravnborg	  before bursting over the PCI/AGP bus. This can increase performance
1725506f1d07SSam Ravnborg	  of image write operations 2.5 times or more. Saying Y here creates a
1726506f1d07SSam Ravnborg	  /proc/mtrr file which may be used to manipulate your processor's
1727506f1d07SSam Ravnborg	  MTRRs. Typically the X server should use this.
1728506f1d07SSam Ravnborg
1729506f1d07SSam Ravnborg	  This code has a reasonably generic interface so that similar
1730506f1d07SSam Ravnborg	  control registers on other processors can be easily supported
1731506f1d07SSam Ravnborg	  as well:
1732506f1d07SSam Ravnborg
1733506f1d07SSam Ravnborg	  The Cyrix 6x86, 6x86MX and M II processors have Address Range
1734506f1d07SSam Ravnborg	  Registers (ARRs) which provide a similar functionality to MTRRs. For
1735506f1d07SSam Ravnborg	  these, the ARRs are used to emulate the MTRRs.
1736506f1d07SSam Ravnborg	  The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1737506f1d07SSam Ravnborg	  MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1738506f1d07SSam Ravnborg	  write-combining. All of these processors are supported by this code
1739506f1d07SSam Ravnborg	  and it makes sense to say Y here if you have one of them.
1740506f1d07SSam Ravnborg
1741506f1d07SSam Ravnborg	  Saying Y here also fixes a problem with buggy SMP BIOSes which only
1742506f1d07SSam Ravnborg	  set the MTRRs for the boot CPU and not for the secondary CPUs. This
1743506f1d07SSam Ravnborg	  can lead to all sorts of problems, so it's good to say Y here.
1744506f1d07SSam Ravnborg
1745506f1d07SSam Ravnborg	  You can safely say Y even if your machine doesn't have MTRRs, you'll
1746506f1d07SSam Ravnborg	  just add about 9 KB to your kernel.
1747506f1d07SSam Ravnborg
17487225e751SRandy Dunlap	  See <file:Documentation/x86/mtrr.txt> for more information.
1749506f1d07SSam Ravnborg
175095ffa243SYinghai Luconfig MTRR_SANITIZER
17512ffb3501SYinghai Lu	def_bool y
175295ffa243SYinghai Lu	prompt "MTRR cleanup support"
175395ffa243SYinghai Lu	depends on MTRR
17548f9ca475SIngo Molnar	---help---
1755aba3728cSThomas Gleixner	  Convert MTRR layout from continuous to discrete, so X drivers can
1756aba3728cSThomas Gleixner	  add writeback entries.
175795ffa243SYinghai Lu
1758aba3728cSThomas Gleixner	  Can be disabled with disable_mtrr_cleanup on the kernel command line.
1759692105b8SMatt LaPlante	  The largest mtrr entry size for a continuous block can be set with
1760aba3728cSThomas Gleixner	  mtrr_chunk_size.
176195ffa243SYinghai Lu
17622ffb3501SYinghai Lu	  If unsure, say Y.
176395ffa243SYinghai Lu
176495ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT
1765f5098d62SYinghai Lu	int "MTRR cleanup enable value (0-1)"
1766f5098d62SYinghai Lu	range 0 1
1767f5098d62SYinghai Lu	default "0"
176895ffa243SYinghai Lu	depends on MTRR_SANITIZER
17698f9ca475SIngo Molnar	---help---
1770f5098d62SYinghai Lu	  Enable mtrr cleanup default value
177195ffa243SYinghai Lu
177212031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
177312031a62SYinghai Lu	int "MTRR cleanup spare reg num (0-7)"
177412031a62SYinghai Lu	range 0 7
177512031a62SYinghai Lu	default "1"
177612031a62SYinghai Lu	depends on MTRR_SANITIZER
17778f9ca475SIngo Molnar	---help---
177812031a62SYinghai Lu	  mtrr cleanup spare entries default, it can be changed via
1779aba3728cSThomas Gleixner	  mtrr_spare_reg_nr=N on the kernel command line.
178012031a62SYinghai Lu
17812e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT
17826fc108a0SJan Beulich	def_bool y
17836a108a14SDavid Rientjes	prompt "x86 PAT support" if EXPERT
17842a8a2719SIngo Molnar	depends on MTRR
17858f9ca475SIngo Molnar	---help---
17862e5d9c85Svenkatesh.pallipadi@intel.com	  Use PAT attributes to setup page level cache control.
1787042b78e4SVenki Pallipadi
17882e5d9c85Svenkatesh.pallipadi@intel.com	  PATs are the modern equivalents of MTRRs and are much more
17892e5d9c85Svenkatesh.pallipadi@intel.com	  flexible than MTRRs.
17902e5d9c85Svenkatesh.pallipadi@intel.com
17912e5d9c85Svenkatesh.pallipadi@intel.com	  Say N here if you see bootup problems (boot crash, boot hang,
1792042b78e4SVenki Pallipadi	  spontaneous reboots) or a non-working video driver.
17932e5d9c85Svenkatesh.pallipadi@intel.com
17942e5d9c85Svenkatesh.pallipadi@intel.com	  If unsure, say Y.
17952e5d9c85Svenkatesh.pallipadi@intel.com
179646cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED
179746cf98cdSVenkatesh Pallipadi	def_bool y
179846cf98cdSVenkatesh Pallipadi	depends on X86_PAT
179946cf98cdSVenkatesh Pallipadi
1800628c6246SH. Peter Anvinconfig ARCH_RANDOM
1801628c6246SH. Peter Anvin	def_bool y
1802628c6246SH. Peter Anvin	prompt "x86 architectural random number generator" if EXPERT
1803628c6246SH. Peter Anvin	---help---
1804628c6246SH. Peter Anvin	  Enable the x86 architectural RDRAND instruction
1805628c6246SH. Peter Anvin	  (Intel Bull Mountain technology) to generate random numbers.
1806628c6246SH. Peter Anvin	  If supported, this is a high bandwidth, cryptographically
1807628c6246SH. Peter Anvin	  secure hardware random number generator.
1808628c6246SH. Peter Anvin
180951ae4a2dSH. Peter Anvinconfig X86_SMAP
181051ae4a2dSH. Peter Anvin	def_bool y
181151ae4a2dSH. Peter Anvin	prompt "Supervisor Mode Access Prevention" if EXPERT
181251ae4a2dSH. Peter Anvin	---help---
181351ae4a2dSH. Peter Anvin	  Supervisor Mode Access Prevention (SMAP) is a security
181451ae4a2dSH. Peter Anvin	  feature in newer Intel processors.  There is a small
181551ae4a2dSH. Peter Anvin	  performance cost if this enabled and turned on; there is
181651ae4a2dSH. Peter Anvin	  also a small increase in the kernel size if this is enabled.
181751ae4a2dSH. Peter Anvin
181851ae4a2dSH. Peter Anvin	  If unsure, say Y.
181951ae4a2dSH. Peter Anvin
182072e9b5feSDave Hansenconfig X86_INTEL_MPX
182172e9b5feSDave Hansen	prompt "Intel MPX (Memory Protection Extensions)"
182272e9b5feSDave Hansen	def_bool n
1823df3735c5SRik van Riel	# Note: only available in 64-bit mode due to VMA flags shortage
1824df3735c5SRik van Riel	depends on CPU_SUP_INTEL && X86_64
1825df3735c5SRik van Riel	select ARCH_USES_HIGH_VMA_FLAGS
182672e9b5feSDave Hansen	---help---
182772e9b5feSDave Hansen	  MPX provides hardware features that can be used in
182872e9b5feSDave Hansen	  conjunction with compiler-instrumented code to check
182972e9b5feSDave Hansen	  memory references.  It is designed to detect buffer
183072e9b5feSDave Hansen	  overflow or underflow bugs.
183172e9b5feSDave Hansen
183272e9b5feSDave Hansen	  This option enables running applications which are
183372e9b5feSDave Hansen	  instrumented or otherwise use MPX.  It does not use MPX
183472e9b5feSDave Hansen	  itself inside the kernel or to protect the kernel
183572e9b5feSDave Hansen	  against bad memory references.
183672e9b5feSDave Hansen
183772e9b5feSDave Hansen	  Enabling this option will make the kernel larger:
183872e9b5feSDave Hansen	  ~8k of kernel text and 36 bytes of data on a 64-bit
183972e9b5feSDave Hansen	  defconfig.  It adds a long to the 'mm_struct' which
184072e9b5feSDave Hansen	  will increase the kernel memory overhead of each
184172e9b5feSDave Hansen	  process and adds some branches to paths used during
184272e9b5feSDave Hansen	  exec() and munmap().
184372e9b5feSDave Hansen
184472e9b5feSDave Hansen	  For details, see Documentation/x86/intel_mpx.txt
184572e9b5feSDave Hansen
184672e9b5feSDave Hansen	  If unsure, say N.
184772e9b5feSDave Hansen
184835e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS
1849284244a9SDave Hansen	prompt "Intel Memory Protection Keys"
185035e97790SDave Hansen	def_bool y
1851284244a9SDave Hansen	# Note: only available in 64-bit mode
185235e97790SDave Hansen	depends on CPU_SUP_INTEL && X86_64
185352c8e601SIngo Molnar	select ARCH_USES_HIGH_VMA_FLAGS
185452c8e601SIngo Molnar	select ARCH_HAS_PKEYS
1855284244a9SDave Hansen	---help---
1856284244a9SDave Hansen	  Memory Protection Keys provides a mechanism for enforcing
1857284244a9SDave Hansen	  page-based protections, but without requiring modification of the
1858284244a9SDave Hansen	  page tables when an application changes protection domains.
1859284244a9SDave Hansen
1860284244a9SDave Hansen	  For details, see Documentation/x86/protection-keys.txt
1861284244a9SDave Hansen
1862284244a9SDave Hansen	  If unsure, say y.
186335e97790SDave Hansen
1864506f1d07SSam Ravnborgconfig EFI
18659ba16087SJan Beulich	bool "EFI runtime service support"
18665b83683fSHuang, Ying	depends on ACPI
1867f6ce5002SSergey Vlasov	select UCS2_STRING
1868022ee6c5SArd Biesheuvel	select EFI_RUNTIME_WRAPPERS
1869506f1d07SSam Ravnborg	---help---
18708b2cb7a8SHuang, Ying	  This enables the kernel to use EFI runtime services that are
1871506f1d07SSam Ravnborg	  available (such as the EFI variable services).
1872506f1d07SSam Ravnborg
18738b2cb7a8SHuang, Ying	  This option is only useful on systems that have EFI firmware.
18748b2cb7a8SHuang, Ying	  In addition, you should use the latest ELILO loader available
18758b2cb7a8SHuang, Ying	  at <http://elilo.sourceforge.net> in order to take advantage
18768b2cb7a8SHuang, Ying	  of EFI runtime services. However, even with this option, the
18778b2cb7a8SHuang, Ying	  resultant kernel should continue to boot on existing non-EFI
18788b2cb7a8SHuang, Ying	  platforms.
1879506f1d07SSam Ravnborg
1880291f3632SMatt Flemingconfig EFI_STUB
1881291f3632SMatt Fleming       bool "EFI stub support"
1882b16d8c23SMatt Fleming       depends on EFI && !X86_USE_3DNOW
18837b2a583aSMatt Fleming       select RELOCATABLE
1884291f3632SMatt Fleming       ---help---
1885291f3632SMatt Fleming          This kernel feature allows a bzImage to be loaded directly
1886291f3632SMatt Fleming	  by EFI firmware without the use of a bootloader.
1887291f3632SMatt Fleming
18884172fe2fSRoy Franz	  See Documentation/efi-stub.txt for more information.
18890c759662SMatt Fleming
18907d453eeeSMatt Flemingconfig EFI_MIXED
18917d453eeeSMatt Fleming	bool "EFI mixed-mode support"
18927d453eeeSMatt Fleming	depends on EFI_STUB && X86_64
18937d453eeeSMatt Fleming	---help---
18947d453eeeSMatt Fleming	   Enabling this feature allows a 64-bit kernel to be booted
18957d453eeeSMatt Fleming	   on a 32-bit firmware, provided that your CPU supports 64-bit
18967d453eeeSMatt Fleming	   mode.
18977d453eeeSMatt Fleming
18987d453eeeSMatt Fleming	   Note that it is not possible to boot a mixed-mode enabled
18997d453eeeSMatt Fleming	   kernel via the EFI boot stub - a bootloader that supports
19007d453eeeSMatt Fleming	   the EFI handover protocol must be used.
19017d453eeeSMatt Fleming
19027d453eeeSMatt Fleming	   If unsure, say N.
19037d453eeeSMatt Fleming
1904506f1d07SSam Ravnborgconfig SECCOMP
19053c2362e6SHarvey Harrison	def_bool y
19063c2362e6SHarvey Harrison	prompt "Enable seccomp to safely compute untrusted bytecode"
19078f9ca475SIngo Molnar	---help---
1908506f1d07SSam Ravnborg	  This kernel feature is useful for number crunching applications
1909506f1d07SSam Ravnborg	  that may need to compute untrusted bytecode during their
1910506f1d07SSam Ravnborg	  execution. By using pipes or other transports made available to
1911506f1d07SSam Ravnborg	  the process as file descriptors supporting the read/write
1912506f1d07SSam Ravnborg	  syscalls, it's possible to isolate those applications in
1913506f1d07SSam Ravnborg	  their own address space using seccomp. Once seccomp is
19149c0bbee8SAlexey Dobriyan	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1915506f1d07SSam Ravnborg	  and the task is only allowed to execute a few safe syscalls
1916506f1d07SSam Ravnborg	  defined by each seccomp mode.
1917506f1d07SSam Ravnborg
1918506f1d07SSam Ravnborg	  If unsure, say Y. Only embedded should say N here.
1919506f1d07SSam Ravnborg
1920506f1d07SSam Ravnborgsource kernel/Kconfig.hz
1921506f1d07SSam Ravnborg
1922506f1d07SSam Ravnborgconfig KEXEC
1923506f1d07SSam Ravnborg	bool "kexec system call"
19242965faa5SDave Young	select KEXEC_CORE
19258f9ca475SIngo Molnar	---help---
1926506f1d07SSam Ravnborg	  kexec is a system call that implements the ability to shutdown your
1927506f1d07SSam Ravnborg	  current kernel, and to start another kernel.  It is like a reboot
1928506f1d07SSam Ravnborg	  but it is independent of the system firmware.   And like a reboot
1929506f1d07SSam Ravnborg	  you can start any kernel with it, not just Linux.
1930506f1d07SSam Ravnborg
1931506f1d07SSam Ravnborg	  The name comes from the similarity to the exec system call.
1932506f1d07SSam Ravnborg
1933506f1d07SSam Ravnborg	  It is an ongoing process to be certain the hardware in a machine
1934506f1d07SSam Ravnborg	  is properly shutdown, so do not be surprised if this code does not
1935bf220695SGeert Uytterhoeven	  initially work for you.  As of this writing the exact hardware
1936bf220695SGeert Uytterhoeven	  interface is strongly in flux, so no good recommendation can be
1937bf220695SGeert Uytterhoeven	  made.
1938506f1d07SSam Ravnborg
193974ca317cSVivek Goyalconfig KEXEC_FILE
194074ca317cSVivek Goyal	bool "kexec file based system call"
19412965faa5SDave Young	select KEXEC_CORE
194274ca317cSVivek Goyal	select BUILD_BIN2C
194374ca317cSVivek Goyal	depends on X86_64
194474ca317cSVivek Goyal	depends on CRYPTO=y
194574ca317cSVivek Goyal	depends on CRYPTO_SHA256=y
194674ca317cSVivek Goyal	---help---
194774ca317cSVivek Goyal	  This is new version of kexec system call. This system call is
194874ca317cSVivek Goyal	  file based and takes file descriptors as system call argument
194974ca317cSVivek Goyal	  for kernel and initramfs as opposed to list of segments as
195074ca317cSVivek Goyal	  accepted by previous system call.
195174ca317cSVivek Goyal
19528e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG
19538e7d8381SVivek Goyal	bool "Verify kernel signature during kexec_file_load() syscall"
195474ca317cSVivek Goyal	depends on KEXEC_FILE
19558e7d8381SVivek Goyal	---help---
19568e7d8381SVivek Goyal	  This option makes kernel signature verification mandatory for
1957d8eb8940SBorislav Petkov	  the kexec_file_load() syscall.
19588e7d8381SVivek Goyal
1959d8eb8940SBorislav Petkov	  In addition to that option, you need to enable signature
1960d8eb8940SBorislav Petkov	  verification for the corresponding kernel image type being
1961d8eb8940SBorislav Petkov	  loaded in order for this to work.
19628e7d8381SVivek Goyal
19638e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG
19648e7d8381SVivek Goyal	bool "Enable bzImage signature verification support"
19658e7d8381SVivek Goyal	depends on KEXEC_VERIFY_SIG
19668e7d8381SVivek Goyal	depends on SIGNED_PE_FILE_VERIFICATION
19678e7d8381SVivek Goyal	select SYSTEM_TRUSTED_KEYRING
19688e7d8381SVivek Goyal	---help---
19698e7d8381SVivek Goyal	  Enable bzImage signature verification support.
19708e7d8381SVivek Goyal
1971506f1d07SSam Ravnborgconfig CRASH_DUMP
197204b69447SPavel Machek	bool "kernel crash dumps"
1973506f1d07SSam Ravnborg	depends on X86_64 || (X86_32 && HIGHMEM)
19748f9ca475SIngo Molnar	---help---
1975506f1d07SSam Ravnborg	  Generate crash dump after being started by kexec.
1976506f1d07SSam Ravnborg	  This should be normally only set in special crash dump kernels
1977506f1d07SSam Ravnborg	  which are loaded in the main kernel with kexec-tools into
1978506f1d07SSam Ravnborg	  a specially reserved region and then later executed after
1979506f1d07SSam Ravnborg	  a crash by kdump/kexec. The crash dump kernel must be compiled
1980506f1d07SSam Ravnborg	  to a memory address not used by the main kernel or BIOS using
1981506f1d07SSam Ravnborg	  PHYSICAL_START, or it must be built as a relocatable image
1982506f1d07SSam Ravnborg	  (CONFIG_RELOCATABLE=y).
1983506f1d07SSam Ravnborg	  For more details see Documentation/kdump/kdump.txt
1984506f1d07SSam Ravnborg
19853ab83521SHuang Yingconfig KEXEC_JUMP
19866ea30386SKees Cook	bool "kexec jump"
1987fee7b0d8SHuang Ying	depends on KEXEC && HIBERNATION
19888f9ca475SIngo Molnar	---help---
198989081d17SHuang Ying	  Jump between original kernel and kexeced kernel and invoke
199089081d17SHuang Ying	  code in physical address mode via KEXEC
19913ab83521SHuang Ying
1992506f1d07SSam Ravnborgconfig PHYSICAL_START
19936a108a14SDavid Rientjes	hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1994ceefccc9SH. Peter Anvin	default "0x1000000"
19958f9ca475SIngo Molnar	---help---
1996506f1d07SSam Ravnborg	  This gives the physical address where the kernel is loaded.
1997506f1d07SSam Ravnborg
1998506f1d07SSam Ravnborg	  If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1999506f1d07SSam Ravnborg	  bzImage will decompress itself to above physical address and
2000506f1d07SSam Ravnborg	  run from there. Otherwise, bzImage will run from the address where
2001506f1d07SSam Ravnborg	  it has been loaded by the boot loader and will ignore above physical
2002506f1d07SSam Ravnborg	  address.
2003506f1d07SSam Ravnborg
2004506f1d07SSam Ravnborg	  In normal kdump cases one does not have to set/change this option
2005506f1d07SSam Ravnborg	  as now bzImage can be compiled as a completely relocatable image
2006506f1d07SSam Ravnborg	  (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2007506f1d07SSam Ravnborg	  address. This option is mainly useful for the folks who don't want
2008506f1d07SSam Ravnborg	  to use a bzImage for capturing the crash dump and want to use a
2009506f1d07SSam Ravnborg	  vmlinux instead. vmlinux is not relocatable hence a kernel needs
2010506f1d07SSam Ravnborg	  to be specifically compiled to run from a specific memory area
2011506f1d07SSam Ravnborg	  (normally a reserved region) and this option comes handy.
2012506f1d07SSam Ravnborg
2013ceefccc9SH. Peter Anvin	  So if you are using bzImage for capturing the crash dump,
2014ceefccc9SH. Peter Anvin	  leave the value here unchanged to 0x1000000 and set
2015ceefccc9SH. Peter Anvin	  CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
2016ceefccc9SH. Peter Anvin	  for capturing the crash dump change this value to start of
2017ceefccc9SH. Peter Anvin	  the reserved region.  In other words, it can be set based on
2018ceefccc9SH. Peter Anvin	  the "X" value as specified in the "crashkernel=YM@XM"
2019ceefccc9SH. Peter Anvin	  command line boot parameter passed to the panic-ed
2020ceefccc9SH. Peter Anvin	  kernel. Please take a look at Documentation/kdump/kdump.txt
2021ceefccc9SH. Peter Anvin	  for more details about crash dumps.
2022506f1d07SSam Ravnborg
2023506f1d07SSam Ravnborg	  Usage of bzImage for capturing the crash dump is recommended as
2024506f1d07SSam Ravnborg	  one does not have to build two kernels. Same kernel can be used
2025506f1d07SSam Ravnborg	  as production kernel and capture kernel. Above option should have
2026506f1d07SSam Ravnborg	  gone away after relocatable bzImage support is introduced. But it
2027506f1d07SSam Ravnborg	  is present because there are users out there who continue to use
2028506f1d07SSam Ravnborg	  vmlinux for dump capture. This option should go away down the
2029506f1d07SSam Ravnborg	  line.
2030506f1d07SSam Ravnborg
2031506f1d07SSam Ravnborg	  Don't change this unless you know what you are doing.
2032506f1d07SSam Ravnborg
2033506f1d07SSam Ravnborgconfig RELOCATABLE
203426717808SH. Peter Anvin	bool "Build a relocatable kernel"
203526717808SH. Peter Anvin	default y
20368f9ca475SIngo Molnar	---help---
2037506f1d07SSam Ravnborg	  This builds a kernel image that retains relocation information
2038506f1d07SSam Ravnborg	  so it can be loaded someplace besides the default 1MB.
2039506f1d07SSam Ravnborg	  The relocations tend to make the kernel binary about 10% larger,
2040506f1d07SSam Ravnborg	  but are discarded at runtime.
2041506f1d07SSam Ravnborg
2042506f1d07SSam Ravnborg	  One use is for the kexec on panic case where the recovery kernel
2043506f1d07SSam Ravnborg	  must live at a different physical address than the primary
2044506f1d07SSam Ravnborg	  kernel.
2045506f1d07SSam Ravnborg
2046506f1d07SSam Ravnborg	  Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2047506f1d07SSam Ravnborg	  it has been loaded at and the compile time physical address
20488ab3820fSKees Cook	  (CONFIG_PHYSICAL_START) is used as the minimum location.
2049506f1d07SSam Ravnborg
20508ab3820fSKees Cookconfig RANDOMIZE_BASE
2051e8581e3dSBaoquan He	bool "Randomize the address of the kernel image (KASLR)"
20528ab3820fSKees Cook	depends on RELOCATABLE
20536807c846SIngo Molnar	default y
20548ab3820fSKees Cook	---help---
2055e8581e3dSBaoquan He	  In support of Kernel Address Space Layout Randomization (KASLR),
2056e8581e3dSBaoquan He	  this randomizes the physical address at which the kernel image
2057e8581e3dSBaoquan He	  is decompressed and the virtual address where the kernel
2058e8581e3dSBaoquan He	  image is mapped, as a security feature that deters exploit
2059e8581e3dSBaoquan He	  attempts relying on knowledge of the location of kernel
2060e8581e3dSBaoquan He	  code internals.
2061e8581e3dSBaoquan He
2062ed9f007eSKees Cook	  On 64-bit, the kernel physical and virtual addresses are
2063ed9f007eSKees Cook	  randomized separately. The physical address will be anywhere
2064ed9f007eSKees Cook	  between 16MB and the top of physical memory (up to 64TB). The
2065ed9f007eSKees Cook	  virtual address will be randomized from 16MB up to 1GB (9 bits
2066ed9f007eSKees Cook	  of entropy). Note that this also reduces the memory space
2067ed9f007eSKees Cook	  available to kernel modules from 1.5GB to 1GB.
2068ed9f007eSKees Cook
2069ed9f007eSKees Cook	  On 32-bit, the kernel physical and virtual addresses are
2070ed9f007eSKees Cook	  randomized together. They will be randomized from 16MB up to
2071ed9f007eSKees Cook	  512MB (8 bits of entropy).
20728ab3820fSKees Cook
2073a653f356SKees Cook	  Entropy is generated using the RDRAND instruction if it is
2074e8581e3dSBaoquan He	  supported. If RDTSC is supported, its value is mixed into
2075e8581e3dSBaoquan He	  the entropy pool as well. If neither RDRAND nor RDTSC are
2076ed9f007eSKees Cook	  supported, then entropy is read from the i8254 timer. The
2077ed9f007eSKees Cook	  usable entropy is limited by the kernel being built using
2078ed9f007eSKees Cook	  2GB addressing, and that PHYSICAL_ALIGN must be at a
2079ed9f007eSKees Cook	  minimum of 2MB. As a result, only 10 bits of entropy are
2080ed9f007eSKees Cook	  theoretically possible, but the implementations are further
2081ed9f007eSKees Cook	  limited due to memory layouts.
2082e8581e3dSBaoquan He
20836807c846SIngo Molnar	  If unsure, say Y.
2084da2b6fb9SKees Cook
20858ab3820fSKees Cook# Relocation on x86 needs some additional build support
2086845adf72SH. Peter Anvinconfig X86_NEED_RELOCS
2087845adf72SH. Peter Anvin	def_bool y
20888ab3820fSKees Cook	depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
2089845adf72SH. Peter Anvin
2090506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN
2091a0215061SKees Cook	hex "Alignment value to which kernel should be aligned"
20928ab3820fSKees Cook	default "0x200000"
2093a0215061SKees Cook	range 0x2000 0x1000000 if X86_32
2094a0215061SKees Cook	range 0x200000 0x1000000 if X86_64
20958f9ca475SIngo Molnar	---help---
2096506f1d07SSam Ravnborg	  This value puts the alignment restrictions on physical address
2097506f1d07SSam Ravnborg	  where kernel is loaded and run from. Kernel is compiled for an
2098506f1d07SSam Ravnborg	  address which meets above alignment restriction.
2099506f1d07SSam Ravnborg
2100506f1d07SSam Ravnborg	  If bootloader loads the kernel at a non-aligned address and
2101506f1d07SSam Ravnborg	  CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2102506f1d07SSam Ravnborg	  address aligned to above value and run from there.
2103506f1d07SSam Ravnborg
2104506f1d07SSam Ravnborg	  If bootloader loads the kernel at a non-aligned address and
2105506f1d07SSam Ravnborg	  CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2106506f1d07SSam Ravnborg	  load address and decompress itself to the address it has been
2107506f1d07SSam Ravnborg	  compiled for and run from there. The address for which kernel is
2108506f1d07SSam Ravnborg	  compiled already meets above alignment restrictions. Hence the
2109506f1d07SSam Ravnborg	  end result is that kernel runs from a physical address meeting
2110506f1d07SSam Ravnborg	  above alignment restrictions.
2111506f1d07SSam Ravnborg
2112a0215061SKees Cook	  On 32-bit this value must be a multiple of 0x2000. On 64-bit
2113a0215061SKees Cook	  this value must be a multiple of 0x200000.
2114a0215061SKees Cook
2115506f1d07SSam Ravnborg	  Don't change this unless you know what you are doing.
2116506f1d07SSam Ravnborg
21170483e1faSThomas Garnierconfig RANDOMIZE_MEMORY
21180483e1faSThomas Garnier	bool "Randomize the kernel memory sections"
21190483e1faSThomas Garnier	depends on X86_64
21200483e1faSThomas Garnier	depends on RANDOMIZE_BASE
21210483e1faSThomas Garnier	default RANDOMIZE_BASE
21220483e1faSThomas Garnier	---help---
21230483e1faSThomas Garnier	   Randomizes the base virtual address of kernel memory sections
21240483e1faSThomas Garnier	   (physical memory mapping, vmalloc & vmemmap). This security feature
21250483e1faSThomas Garnier	   makes exploits relying on predictable memory locations less reliable.
21260483e1faSThomas Garnier
21270483e1faSThomas Garnier	   The order of allocations remains unchanged. Entropy is generated in
21280483e1faSThomas Garnier	   the same way as RANDOMIZE_BASE. Current implementation in the optimal
21290483e1faSThomas Garnier	   configuration have in average 30,000 different possible virtual
21300483e1faSThomas Garnier	   addresses for each memory section.
21310483e1faSThomas Garnier
21326807c846SIngo Molnar	   If unsure, say Y.
21330483e1faSThomas Garnier
213490397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING
213590397a41SThomas Garnier	hex "Physical memory mapping padding" if EXPERT
213690397a41SThomas Garnier	depends on RANDOMIZE_MEMORY
213790397a41SThomas Garnier	default "0xa" if MEMORY_HOTPLUG
213890397a41SThomas Garnier	default "0x0"
213990397a41SThomas Garnier	range 0x1 0x40 if MEMORY_HOTPLUG
214090397a41SThomas Garnier	range 0x0 0x40
214190397a41SThomas Garnier	---help---
214290397a41SThomas Garnier	   Define the padding in terabytes added to the existing physical
214390397a41SThomas Garnier	   memory size during kernel memory randomization. It is useful
214490397a41SThomas Garnier	   for memory hotplug support but reduces the entropy available for
214590397a41SThomas Garnier	   address randomization.
214690397a41SThomas Garnier
214790397a41SThomas Garnier	   If unsure, leave at the default value.
214890397a41SThomas Garnier
2149506f1d07SSam Ravnborgconfig HOTPLUG_CPU
21507c13e6a3SDimitri Sivanich	bool "Support for hot-pluggable CPUs"
215140b31360SStephen Rothwell	depends on SMP
2152506f1d07SSam Ravnborg	---help---
21537c13e6a3SDimitri Sivanich	  Say Y here to allow turning CPUs off and on. CPUs can be
21547c13e6a3SDimitri Sivanich	  controlled through /sys/devices/system/cpu.
21557c13e6a3SDimitri Sivanich	  ( Note: power management support will enable this option
21567c13e6a3SDimitri Sivanich	    automatically on SMP systems. )
21577c13e6a3SDimitri Sivanich	  Say N if you want to disable CPU hotplug.
2158506f1d07SSam Ravnborg
215980aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0
216080aa1dffSFenghua Yu	bool "Set default setting of cpu0_hotpluggable"
216180aa1dffSFenghua Yu	default n
21622c922cd0SKees Cook	depends on HOTPLUG_CPU
216380aa1dffSFenghua Yu	---help---
216480aa1dffSFenghua Yu	  Set whether default state of cpu0_hotpluggable is on or off.
216580aa1dffSFenghua Yu
216680aa1dffSFenghua Yu	  Say Y here to enable CPU0 hotplug by default. If this switch
216780aa1dffSFenghua Yu	  is turned on, there is no need to give cpu0_hotplug kernel
216880aa1dffSFenghua Yu	  parameter and the CPU0 hotplug feature is enabled by default.
216980aa1dffSFenghua Yu
217080aa1dffSFenghua Yu	  Please note: there are two known CPU0 dependencies if you want
217180aa1dffSFenghua Yu	  to enable the CPU0 hotplug feature either by this switch or by
217280aa1dffSFenghua Yu	  cpu0_hotplug kernel parameter.
217380aa1dffSFenghua Yu
217480aa1dffSFenghua Yu	  First, resume from hibernate or suspend always starts from CPU0.
217580aa1dffSFenghua Yu	  So hibernate and suspend are prevented if CPU0 is offline.
217680aa1dffSFenghua Yu
217780aa1dffSFenghua Yu	  Second dependency is PIC interrupts always go to CPU0. CPU0 can not
217880aa1dffSFenghua Yu	  offline if any interrupt can not migrate out of CPU0. There may
217980aa1dffSFenghua Yu	  be other CPU0 dependencies.
218080aa1dffSFenghua Yu
218180aa1dffSFenghua Yu	  Please make sure the dependencies are under your control before
218280aa1dffSFenghua Yu	  you enable this feature.
218380aa1dffSFenghua Yu
218480aa1dffSFenghua Yu	  Say N if you don't want to enable CPU0 hotplug feature by default.
218580aa1dffSFenghua Yu	  You still can enable the CPU0 hotplug feature at boot by kernel
218680aa1dffSFenghua Yu	  parameter cpu0_hotplug.
218780aa1dffSFenghua Yu
2188a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0
2189a71c8bc5SFenghua Yu	def_bool n
2190a71c8bc5SFenghua Yu	prompt "Debug CPU0 hotplug"
21912c922cd0SKees Cook	depends on HOTPLUG_CPU
2192a71c8bc5SFenghua Yu	---help---
2193a71c8bc5SFenghua Yu	  Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2194a71c8bc5SFenghua Yu	  soon as possible and boots up userspace with CPU0 offlined. User
2195a71c8bc5SFenghua Yu	  can online CPU0 back after boot time.
2196a71c8bc5SFenghua Yu
2197a71c8bc5SFenghua Yu	  To debug CPU0 hotplug, you need to enable CPU0 offline/online
2198a71c8bc5SFenghua Yu	  feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2199a71c8bc5SFenghua Yu	  compilation or giving cpu0_hotplug kernel parameter at boot.
2200a71c8bc5SFenghua Yu
2201a71c8bc5SFenghua Yu	  If unsure, say N.
2202a71c8bc5SFenghua Yu
2203506f1d07SSam Ravnborgconfig COMPAT_VDSO
2204b0b49f26SAndy Lutomirski	def_bool n
2205b0b49f26SAndy Lutomirski	prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
2206953fee1dSIngo Molnar	depends on COMPAT_32
22078f9ca475SIngo Molnar	---help---
2208b0b49f26SAndy Lutomirski	  Certain buggy versions of glibc will crash if they are
2209b0b49f26SAndy Lutomirski	  presented with a 32-bit vDSO that is not mapped at the address
2210b0b49f26SAndy Lutomirski	  indicated in its segment table.
2211e84446deSRandy Dunlap
2212b0b49f26SAndy Lutomirski	  The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2213b0b49f26SAndy Lutomirski	  and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2214b0b49f26SAndy Lutomirski	  49ad572a70b8aeb91e57483a11dd1b77e31c4468.  Glibc 2.3.3 is
2215b0b49f26SAndy Lutomirski	  the only released version with the bug, but OpenSUSE 9
2216b0b49f26SAndy Lutomirski	  contains a buggy "glibc 2.3.2".
2217506f1d07SSam Ravnborg
2218b0b49f26SAndy Lutomirski	  The symptom of the bug is that everything crashes on startup, saying:
2219b0b49f26SAndy Lutomirski	  dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2220b0b49f26SAndy Lutomirski
2221b0b49f26SAndy Lutomirski	  Saying Y here changes the default value of the vdso32 boot
2222b0b49f26SAndy Lutomirski	  option from 1 to 0, which turns off the 32-bit vDSO entirely.
2223b0b49f26SAndy Lutomirski	  This works around the glibc bug but hurts performance.
2224b0b49f26SAndy Lutomirski
2225b0b49f26SAndy Lutomirski	  If unsure, say N: if you are compiling your own kernel, you
2226b0b49f26SAndy Lutomirski	  are unlikely to be using a buggy version of glibc.
2227506f1d07SSam Ravnborg
22283dc33bd3SKees Cookchoice
22293dc33bd3SKees Cook	prompt "vsyscall table for legacy applications"
22303dc33bd3SKees Cook	depends on X86_64
22313dc33bd3SKees Cook	default LEGACY_VSYSCALL_EMULATE
22323dc33bd3SKees Cook	help
22333dc33bd3SKees Cook	  Legacy user code that does not know how to find the vDSO expects
22343dc33bd3SKees Cook	  to be able to issue three syscalls by calling fixed addresses in
22353dc33bd3SKees Cook	  kernel space. Since this location is not randomized with ASLR,
22363dc33bd3SKees Cook	  it can be used to assist security vulnerability exploitation.
22373dc33bd3SKees Cook
22383dc33bd3SKees Cook	  This setting can be changed at boot time via the kernel command
22393dc33bd3SKees Cook	  line parameter vsyscall=[native|emulate|none].
22403dc33bd3SKees Cook
22413dc33bd3SKees Cook	  On a system with recent enough glibc (2.14 or newer) and no
22423dc33bd3SKees Cook	  static binaries, you can say None without a performance penalty
22433dc33bd3SKees Cook	  to improve security.
22443dc33bd3SKees Cook
22453dc33bd3SKees Cook	  If unsure, select "Emulate".
22463dc33bd3SKees Cook
22473dc33bd3SKees Cook	config LEGACY_VSYSCALL_NATIVE
22483dc33bd3SKees Cook		bool "Native"
22493dc33bd3SKees Cook		help
22503dc33bd3SKees Cook		  Actual executable code is located in the fixed vsyscall
22513dc33bd3SKees Cook		  address mapping, implementing time() efficiently. Since
22523dc33bd3SKees Cook		  this makes the mapping executable, it can be used during
22533dc33bd3SKees Cook		  security vulnerability exploitation (traditionally as
22543dc33bd3SKees Cook		  ROP gadgets). This configuration is not recommended.
22553dc33bd3SKees Cook
22563dc33bd3SKees Cook	config LEGACY_VSYSCALL_EMULATE
22573dc33bd3SKees Cook		bool "Emulate"
22583dc33bd3SKees Cook		help
22593dc33bd3SKees Cook		  The kernel traps and emulates calls into the fixed
22603dc33bd3SKees Cook		  vsyscall address mapping. This makes the mapping
22613dc33bd3SKees Cook		  non-executable, but it still contains known contents,
22623dc33bd3SKees Cook		  which could be used in certain rare security vulnerability
22633dc33bd3SKees Cook		  exploits. This configuration is recommended when userspace
22643dc33bd3SKees Cook		  still uses the vsyscall area.
22653dc33bd3SKees Cook
22663dc33bd3SKees Cook	config LEGACY_VSYSCALL_NONE
22673dc33bd3SKees Cook		bool "None"
22683dc33bd3SKees Cook		help
22693dc33bd3SKees Cook		  There will be no vsyscall mapping at all. This will
22703dc33bd3SKees Cook		  eliminate any risk of ASLR bypass due to the vsyscall
22713dc33bd3SKees Cook		  fixed address mapping. Attempts to use the vsyscalls
22723dc33bd3SKees Cook		  will be reported to dmesg, so that either old or
22733dc33bd3SKees Cook		  malicious userspace programs can be identified.
22743dc33bd3SKees Cook
22753dc33bd3SKees Cookendchoice
22763dc33bd3SKees Cook
2277516cbf37STim Birdconfig CMDLINE_BOOL
2278516cbf37STim Bird	bool "Built-in kernel command line"
22798f9ca475SIngo Molnar	---help---
2280516cbf37STim Bird	  Allow for specifying boot arguments to the kernel at
2281516cbf37STim Bird	  build time.  On some systems (e.g. embedded ones), it is
2282516cbf37STim Bird	  necessary or convenient to provide some or all of the
2283516cbf37STim Bird	  kernel boot arguments with the kernel itself (that is,
2284516cbf37STim Bird	  to not rely on the boot loader to provide them.)
2285516cbf37STim Bird
2286516cbf37STim Bird	  To compile command line arguments into the kernel,
2287516cbf37STim Bird	  set this option to 'Y', then fill in the
228869711ca1SSébastien Hinderer	  boot arguments in CONFIG_CMDLINE.
2289516cbf37STim Bird
2290516cbf37STim Bird	  Systems with fully functional boot loaders (i.e. non-embedded)
2291516cbf37STim Bird	  should leave this option set to 'N'.
2292516cbf37STim Bird
2293516cbf37STim Birdconfig CMDLINE
2294516cbf37STim Bird	string "Built-in kernel command string"
2295516cbf37STim Bird	depends on CMDLINE_BOOL
2296516cbf37STim Bird	default ""
22978f9ca475SIngo Molnar	---help---
2298516cbf37STim Bird	  Enter arguments here that should be compiled into the kernel
2299516cbf37STim Bird	  image and used at boot time.  If the boot loader provides a
2300516cbf37STim Bird	  command line at boot time, it is appended to this string to
2301516cbf37STim Bird	  form the full kernel command line, when the system boots.
2302516cbf37STim Bird
2303516cbf37STim Bird	  However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2304516cbf37STim Bird	  change this behavior.
2305516cbf37STim Bird
2306516cbf37STim Bird	  In most cases, the command line (whether built-in or provided
2307516cbf37STim Bird	  by the boot loader) should specify the device for the root
2308516cbf37STim Bird	  file system.
2309516cbf37STim Bird
2310516cbf37STim Birdconfig CMDLINE_OVERRIDE
2311516cbf37STim Bird	bool "Built-in command line overrides boot loader arguments"
2312516cbf37STim Bird	depends on CMDLINE_BOOL
23138f9ca475SIngo Molnar	---help---
2314516cbf37STim Bird	  Set this option to 'Y' to have the kernel ignore the boot loader
2315516cbf37STim Bird	  command line, and use ONLY the built-in command line.
2316516cbf37STim Bird
2317516cbf37STim Bird	  This is used to work around broken boot loaders.  This should
2318516cbf37STim Bird	  be set to 'N' under normal conditions.
2319516cbf37STim Bird
2320a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL
2321a5b9e5a2SAndy Lutomirski	bool "Enable the LDT (local descriptor table)" if EXPERT
2322a5b9e5a2SAndy Lutomirski	default y
2323a5b9e5a2SAndy Lutomirski	---help---
2324a5b9e5a2SAndy Lutomirski	  Linux can allow user programs to install a per-process x86
2325a5b9e5a2SAndy Lutomirski	  Local Descriptor Table (LDT) using the modify_ldt(2) system
2326a5b9e5a2SAndy Lutomirski	  call.  This is required to run 16-bit or segmented code such as
2327a5b9e5a2SAndy Lutomirski	  DOSEMU or some Wine programs.  It is also used by some very old
2328a5b9e5a2SAndy Lutomirski	  threading libraries.
2329a5b9e5a2SAndy Lutomirski
2330a5b9e5a2SAndy Lutomirski	  Enabling this feature adds a small amount of overhead to
2331a5b9e5a2SAndy Lutomirski	  context switches and increases the low-level kernel attack
2332a5b9e5a2SAndy Lutomirski	  surface.  Disabling it removes the modify_ldt(2) system call.
2333a5b9e5a2SAndy Lutomirski
2334a5b9e5a2SAndy Lutomirski	  Saying 'N' here may make sense for embedded or server kernels.
2335a5b9e5a2SAndy Lutomirski
2336b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig"
2337b700e7f0SSeth Jennings
2338506f1d07SSam Ravnborgendmenu
2339506f1d07SSam Ravnborg
23403072e413SMichal Hockoconfig ARCH_HAS_ADD_PAGES
23413072e413SMichal Hocko	def_bool y
23423072e413SMichal Hocko	depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
23433072e413SMichal Hocko
2344506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG
2345506f1d07SSam Ravnborg	def_bool y
2346506f1d07SSam Ravnborg	depends on X86_64 || (X86_32 && HIGHMEM)
2347506f1d07SSam Ravnborg
234835551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE
234935551053SGary Hade	def_bool y
235035551053SGary Hade	depends on MEMORY_HOTPLUG
235135551053SGary Hade
2352e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID
2353645a7919STejun Heo	def_bool y
2354e534c7c5SLee Schermerhorn	depends on NUMA
2355e534c7c5SLee Schermerhorn
23569491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK
23579491846fSKirill A. Shutemov	def_bool y
23589491846fSKirill A. Shutemov	depends on X86_64 || X86_PAE
23599491846fSKirill A. Shutemov
2360c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION
2361c177c81eSNaoya Horiguchi	def_bool y
2362c177c81eSNaoya Horiguchi	depends on X86_64 && HUGETLB_PAGE && MIGRATION
2363c177c81eSNaoya Horiguchi
23649c670ea3SNaoya Horiguchiconfig ARCH_ENABLE_THP_MIGRATION
23659c670ea3SNaoya Horiguchi	def_bool y
23669c670ea3SNaoya Horiguchi	depends on X86_64 && TRANSPARENT_HUGEPAGE
23679c670ea3SNaoya Horiguchi
2368da85f865SBjorn Helgaasmenu "Power management and ACPI options"
2369e279b6c1SSam Ravnborg
2370e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER
23713c2362e6SHarvey Harrison	def_bool y
2372e279b6c1SSam Ravnborg	depends on X86_64 && HIBERNATION
2373e279b6c1SSam Ravnborg
2374e279b6c1SSam Ravnborgsource "kernel/power/Kconfig"
2375e279b6c1SSam Ravnborg
2376e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig"
2377e279b6c1SSam Ravnborg
2378efafc8b2SFeng Tangsource "drivers/sfi/Kconfig"
2379efafc8b2SFeng Tang
2380a6b68076SAndi Kleenconfig X86_APM_BOOT
23816fc108a0SJan Beulich	def_bool y
2382282e5aabSPaul Bolle	depends on APM
2383a6b68076SAndi Kleen
2384e279b6c1SSam Ravnborgmenuconfig APM
2385e279b6c1SSam Ravnborg	tristate "APM (Advanced Power Management) BIOS support"
2386efefa6f6SIngo Molnar	depends on X86_32 && PM_SLEEP
2387e279b6c1SSam Ravnborg	---help---
2388e279b6c1SSam Ravnborg	  APM is a BIOS specification for saving power using several different
2389e279b6c1SSam Ravnborg	  techniques. This is mostly useful for battery powered laptops with
2390e279b6c1SSam Ravnborg	  APM compliant BIOSes. If you say Y here, the system time will be
2391e279b6c1SSam Ravnborg	  reset after a RESUME operation, the /proc/apm device will provide
2392e279b6c1SSam Ravnborg	  battery status information, and user-space programs will receive
2393e279b6c1SSam Ravnborg	  notification of APM "events" (e.g. battery status change).
2394e279b6c1SSam Ravnborg
2395e279b6c1SSam Ravnborg	  If you select "Y" here, you can disable actual use of the APM
2396e279b6c1SSam Ravnborg	  BIOS by passing the "apm=off" option to the kernel at boot time.
2397e279b6c1SSam Ravnborg
2398e279b6c1SSam Ravnborg	  Note that the APM support is almost completely disabled for
2399e279b6c1SSam Ravnborg	  machines with more than one CPU.
2400e279b6c1SSam Ravnborg
2401e279b6c1SSam Ravnborg	  In order to use APM, you will need supporting software. For location
24022dc98fd3SMichael Witten	  and more information, read <file:Documentation/power/apm-acpi.txt>
24032dc98fd3SMichael Witten	  and the Battery Powered Linux mini-HOWTO, available from
2404e279b6c1SSam Ravnborg	  <http://www.tldp.org/docs.html#howto>.
2405e279b6c1SSam Ravnborg
2406e279b6c1SSam Ravnborg	  This driver does not spin down disk drives (see the hdparm(8)
2407e279b6c1SSam Ravnborg	  manpage ("man 8 hdparm") for that), and it doesn't turn off
2408e279b6c1SSam Ravnborg	  VESA-compliant "green" monitors.
2409e279b6c1SSam Ravnborg
2410e279b6c1SSam Ravnborg	  This driver does not support the TI 4000M TravelMate and the ACER
2411e279b6c1SSam Ravnborg	  486/DX4/75 because they don't have compliant BIOSes. Many "green"
2412e279b6c1SSam Ravnborg	  desktop machines also don't have compliant BIOSes, and this driver
2413e279b6c1SSam Ravnborg	  may cause those machines to panic during the boot phase.
2414e279b6c1SSam Ravnborg
2415e279b6c1SSam Ravnborg	  Generally, if you don't have a battery in your machine, there isn't
2416e279b6c1SSam Ravnborg	  much point in using this driver and you should say N. If you get
2417e279b6c1SSam Ravnborg	  random kernel OOPSes or reboots that don't seem to be related to
2418e279b6c1SSam Ravnborg	  anything, try disabling/enabling this option (or disabling/enabling
2419e279b6c1SSam Ravnborg	  APM in your BIOS).
2420e279b6c1SSam Ravnborg
2421e279b6c1SSam Ravnborg	  Some other things you should try when experiencing seemingly random,
2422e279b6c1SSam Ravnborg	  "weird" problems:
2423e279b6c1SSam Ravnborg
2424e279b6c1SSam Ravnborg	  1) make sure that you have enough swap space and that it is
2425e279b6c1SSam Ravnborg	  enabled.
2426e279b6c1SSam Ravnborg	  2) pass the "no-hlt" option to the kernel
2427e279b6c1SSam Ravnborg	  3) switch on floating point emulation in the kernel and pass
2428e279b6c1SSam Ravnborg	  the "no387" option to the kernel
2429e279b6c1SSam Ravnborg	  4) pass the "floppy=nodma" option to the kernel
2430e279b6c1SSam Ravnborg	  5) pass the "mem=4M" option to the kernel (thereby disabling
2431e279b6c1SSam Ravnborg	  all but the first 4 MB of RAM)
2432e279b6c1SSam Ravnborg	  6) make sure that the CPU is not over clocked.
2433e279b6c1SSam Ravnborg	  7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2434e279b6c1SSam Ravnborg	  8) disable the cache from your BIOS settings
2435e279b6c1SSam Ravnborg	  9) install a fan for the video card or exchange video RAM
2436e279b6c1SSam Ravnborg	  10) install a better fan for the CPU
2437e279b6c1SSam Ravnborg	  11) exchange RAM chips
2438e279b6c1SSam Ravnborg	  12) exchange the motherboard.
2439e279b6c1SSam Ravnborg
2440e279b6c1SSam Ravnborg	  To compile this driver as a module, choose M here: the
2441e279b6c1SSam Ravnborg	  module will be called apm.
2442e279b6c1SSam Ravnborg
2443e279b6c1SSam Ravnborgif APM
2444e279b6c1SSam Ravnborg
2445e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND
2446e279b6c1SSam Ravnborg	bool "Ignore USER SUSPEND"
24478f9ca475SIngo Molnar	---help---
2448e279b6c1SSam Ravnborg	  This option will ignore USER SUSPEND requests. On machines with a
2449e279b6c1SSam Ravnborg	  compliant APM BIOS, you want to say N. However, on the NEC Versa M
2450e279b6c1SSam Ravnborg	  series notebooks, it is necessary to say Y because of a BIOS bug.
2451e279b6c1SSam Ravnborg
2452e279b6c1SSam Ravnborgconfig APM_DO_ENABLE
2453e279b6c1SSam Ravnborg	bool "Enable PM at boot time"
2454e279b6c1SSam Ravnborg	---help---
2455e279b6c1SSam Ravnborg	  Enable APM features at boot time. From page 36 of the APM BIOS
2456e279b6c1SSam Ravnborg	  specification: "When disabled, the APM BIOS does not automatically
2457e279b6c1SSam Ravnborg	  power manage devices, enter the Standby State, enter the Suspend
2458e279b6c1SSam Ravnborg	  State, or take power saving steps in response to CPU Idle calls."
2459e279b6c1SSam Ravnborg	  This driver will make CPU Idle calls when Linux is idle (unless this
2460e279b6c1SSam Ravnborg	  feature is turned off -- see "Do CPU IDLE calls", below). This
2461e279b6c1SSam Ravnborg	  should always save battery power, but more complicated APM features
2462e279b6c1SSam Ravnborg	  will be dependent on your BIOS implementation. You may need to turn
2463e279b6c1SSam Ravnborg	  this option off if your computer hangs at boot time when using APM
2464e279b6c1SSam Ravnborg	  support, or if it beeps continuously instead of suspending. Turn
2465e279b6c1SSam Ravnborg	  this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2466e279b6c1SSam Ravnborg	  T400CDT. This is off by default since most machines do fine without
2467e279b6c1SSam Ravnborg	  this feature.
2468e279b6c1SSam Ravnborg
2469e279b6c1SSam Ravnborgconfig APM_CPU_IDLE
2470dd8af076SLen Brown	depends on CPU_IDLE
2471e279b6c1SSam Ravnborg	bool "Make CPU Idle calls when idle"
24728f9ca475SIngo Molnar	---help---
2473e279b6c1SSam Ravnborg	  Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2474e279b6c1SSam Ravnborg	  On some machines, this can activate improved power savings, such as
2475e279b6c1SSam Ravnborg	  a slowed CPU clock rate, when the machine is idle. These idle calls
2476e279b6c1SSam Ravnborg	  are made after the idle loop has run for some length of time (e.g.,
2477e279b6c1SSam Ravnborg	  333 mS). On some machines, this will cause a hang at boot time or
2478e279b6c1SSam Ravnborg	  whenever the CPU becomes idle. (On machines with more than one CPU,
2479e279b6c1SSam Ravnborg	  this option does nothing.)
2480e279b6c1SSam Ravnborg
2481e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK
2482e279b6c1SSam Ravnborg	bool "Enable console blanking using APM"
24838f9ca475SIngo Molnar	---help---
2484e279b6c1SSam Ravnborg	  Enable console blanking using the APM. Some laptops can use this to
2485e279b6c1SSam Ravnborg	  turn off the LCD backlight when the screen blanker of the Linux
2486e279b6c1SSam Ravnborg	  virtual console blanks the screen. Note that this is only used by
2487e279b6c1SSam Ravnborg	  the virtual console screen blanker, and won't turn off the backlight
2488e279b6c1SSam Ravnborg	  when using the X Window system. This also doesn't have anything to
2489e279b6c1SSam Ravnborg	  do with your VESA-compliant power-saving monitor. Further, this
2490e279b6c1SSam Ravnborg	  option doesn't work for all laptops -- it might not turn off your
2491e279b6c1SSam Ravnborg	  backlight at all, or it might print a lot of errors to the console,
2492e279b6c1SSam Ravnborg	  especially if you are using gpm.
2493e279b6c1SSam Ravnborg
2494e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS
2495e279b6c1SSam Ravnborg	bool "Allow interrupts during APM BIOS calls"
24968f9ca475SIngo Molnar	---help---
2497e279b6c1SSam Ravnborg	  Normally we disable external interrupts while we are making calls to
2498e279b6c1SSam Ravnborg	  the APM BIOS as a measure to lessen the effects of a badly behaving
2499e279b6c1SSam Ravnborg	  BIOS implementation.  The BIOS should reenable interrupts if it
2500e279b6c1SSam Ravnborg	  needs to.  Unfortunately, some BIOSes do not -- especially those in
2501e279b6c1SSam Ravnborg	  many of the newer IBM Thinkpads.  If you experience hangs when you
2502e279b6c1SSam Ravnborg	  suspend, try setting this to Y.  Otherwise, say N.
2503e279b6c1SSam Ravnborg
2504e279b6c1SSam Ravnborgendif # APM
2505e279b6c1SSam Ravnborg
2506bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig"
2507e279b6c1SSam Ravnborg
2508e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig"
2509e279b6c1SSam Ravnborg
251027471fdbSAndy Henroidsource "drivers/idle/Kconfig"
251127471fdbSAndy Henroid
2512e279b6c1SSam Ravnborgendmenu
2513e279b6c1SSam Ravnborg
2514e279b6c1SSam Ravnborg
2515e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)"
2516e279b6c1SSam Ravnborg
2517e279b6c1SSam Ravnborgconfig PCI
25181ac97018SIngo Molnar	bool "PCI support"
25191c858087SAdrian Bunk	default y
25208f9ca475SIngo Molnar	---help---
2521e279b6c1SSam Ravnborg	  Find out whether you have a PCI motherboard. PCI is the name of a
2522e279b6c1SSam Ravnborg	  bus system, i.e. the way the CPU talks to the other stuff inside
2523e279b6c1SSam Ravnborg	  your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2524e279b6c1SSam Ravnborg	  VESA. If you have PCI, say Y, otherwise N.
2525e279b6c1SSam Ravnborg
2526e279b6c1SSam Ravnborgchoice
2527e279b6c1SSam Ravnborg	prompt "PCI access mode"
2528efefa6f6SIngo Molnar	depends on X86_32 && PCI
2529e279b6c1SSam Ravnborg	default PCI_GOANY
2530e279b6c1SSam Ravnborg	---help---
2531e279b6c1SSam Ravnborg	  On PCI systems, the BIOS can be used to detect the PCI devices and
2532e279b6c1SSam Ravnborg	  determine their configuration. However, some old PCI motherboards
2533e279b6c1SSam Ravnborg	  have BIOS bugs and may crash if this is done. Also, some embedded
2534e279b6c1SSam Ravnborg	  PCI-based systems don't have any BIOS at all. Linux can also try to
2535e279b6c1SSam Ravnborg	  detect the PCI hardware directly without using the BIOS.
2536e279b6c1SSam Ravnborg
2537e279b6c1SSam Ravnborg	  With this option, you can specify how Linux should detect the
2538e279b6c1SSam Ravnborg	  PCI devices. If you choose "BIOS", the BIOS will be used,
2539e279b6c1SSam Ravnborg	  if you choose "Direct", the BIOS won't be used, and if you
2540e279b6c1SSam Ravnborg	  choose "MMConfig", then PCI Express MMCONFIG will be used.
2541e279b6c1SSam Ravnborg	  If you choose "Any", the kernel will try MMCONFIG, then the
2542e279b6c1SSam Ravnborg	  direct access method and falls back to the BIOS if that doesn't
2543e279b6c1SSam Ravnborg	  work. If unsure, go with the default, which is "Any".
2544e279b6c1SSam Ravnborg
2545e279b6c1SSam Ravnborgconfig PCI_GOBIOS
2546e279b6c1SSam Ravnborg	bool "BIOS"
2547e279b6c1SSam Ravnborg
2548e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG
2549e279b6c1SSam Ravnborg	bool "MMConfig"
2550e279b6c1SSam Ravnborg
2551e279b6c1SSam Ravnborgconfig PCI_GODIRECT
2552e279b6c1SSam Ravnborg	bool "Direct"
2553e279b6c1SSam Ravnborg
25543ef0e1f8SAndres Salomonconfig PCI_GOOLPC
255576fb6570SDaniel Drake	bool "OLPC XO-1"
25563ef0e1f8SAndres Salomon	depends on OLPC
25573ef0e1f8SAndres Salomon
25582bdd1b03SAndres Salomonconfig PCI_GOANY
25592bdd1b03SAndres Salomon	bool "Any"
25602bdd1b03SAndres Salomon
2561e279b6c1SSam Ravnborgendchoice
2562e279b6c1SSam Ravnborg
2563e279b6c1SSam Ravnborgconfig PCI_BIOS
25643c2362e6SHarvey Harrison	def_bool y
2565efefa6f6SIngo Molnar	depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2566e279b6c1SSam Ravnborg
2567e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2568e279b6c1SSam Ravnborgconfig PCI_DIRECT
25693c2362e6SHarvey Harrison	def_bool y
25700aba496fSShaohua Li	depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2571e279b6c1SSam Ravnborg
2572e279b6c1SSam Ravnborgconfig PCI_MMCONFIG
25733c2362e6SHarvey Harrison	def_bool y
25745f0db7a2SFeng Tang	depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2575e279b6c1SSam Ravnborg
25763ef0e1f8SAndres Salomonconfig PCI_OLPC
25772bdd1b03SAndres Salomon	def_bool y
25782bdd1b03SAndres Salomon	depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
25793ef0e1f8SAndres Salomon
2580b5401a96SAlex Nixonconfig PCI_XEN
2581b5401a96SAlex Nixon	def_bool y
2582b5401a96SAlex Nixon	depends on PCI && XEN
2583b5401a96SAlex Nixon	select SWIOTLB_XEN
2584b5401a96SAlex Nixon
2585e279b6c1SSam Ravnborgconfig PCI_DOMAINS
25863c2362e6SHarvey Harrison	def_bool y
2587e279b6c1SSam Ravnborg	depends on PCI
2588e279b6c1SSam Ravnborg
2589e279b6c1SSam Ravnborgconfig PCI_MMCONFIG
2590e279b6c1SSam Ravnborg	bool "Support mmconfig PCI config space access"
2591e279b6c1SSam Ravnborg	depends on X86_64 && PCI && ACPI
2592e279b6c1SSam Ravnborg
25933f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK
25946a108a14SDavid Rientjes	bool "Read CNB20LE Host Bridge Windows" if EXPERT
25956ea30386SKees Cook	depends on PCI
25963f6ea84aSIra W. Snyder	help
25973f6ea84aSIra W. Snyder	  Read the PCI windows out of the CNB20LE host bridge. This allows
25983f6ea84aSIra W. Snyder	  PCI hotplug to work on systems with the CNB20LE chipset which do
25993f6ea84aSIra W. Snyder	  not have ACPI.
26003f6ea84aSIra W. Snyder
260164a5fed6SBjorn Helgaas	  There's no public spec for this chipset, and this functionality
260264a5fed6SBjorn Helgaas	  is known to be incomplete.
260364a5fed6SBjorn Helgaas
260464a5fed6SBjorn Helgaas	  You should say N unless you know you need this.
260564a5fed6SBjorn Helgaas
2606e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig"
2607e279b6c1SSam Ravnborg
26083a495511SWilliam Breathitt Grayconfig ISA_BUS
26093a495511SWilliam Breathitt Gray	bool "ISA-style bus support on modern systems" if EXPERT
26103a495511SWilliam Breathitt Gray	select ISA_BUS_API
26113a495511SWilliam Breathitt Gray	help
26123a495511SWilliam Breathitt Gray	  Enables ISA-style drivers on modern systems. This is necessary to
26133a495511SWilliam Breathitt Gray	  support PC/104 devices on X86_64 platforms.
26143a495511SWilliam Breathitt Gray
26153a495511SWilliam Breathitt Gray	  If unsure, say N.
26163a495511SWilliam Breathitt Gray
26171c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA.
2618e279b6c1SSam Ravnborgconfig ISA_DMA_API
26191c00f016SDavid Rientjes	bool "ISA-style DMA support" if (X86_64 && EXPERT)
26201c00f016SDavid Rientjes	default y
26211c00f016SDavid Rientjes	help
26221c00f016SDavid Rientjes	  Enables ISA-style DMA support for devices requiring such controllers.
26231c00f016SDavid Rientjes	  If unsure, say Y.
2624e279b6c1SSam Ravnborg
262551e68d05SLinus Torvaldsif X86_32
262651e68d05SLinus Torvalds
2627e279b6c1SSam Ravnborgconfig ISA
2628e279b6c1SSam Ravnborg	bool "ISA support"
26298f9ca475SIngo Molnar	---help---
2630e279b6c1SSam Ravnborg	  Find out whether you have ISA slots on your motherboard.  ISA is the
2631e279b6c1SSam Ravnborg	  name of a bus system, i.e. the way the CPU talks to the other stuff
2632e279b6c1SSam Ravnborg	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
2633e279b6c1SSam Ravnborg	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2634e279b6c1SSam Ravnborg	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
2635e279b6c1SSam Ravnborg
2636e279b6c1SSam Ravnborgconfig EISA
2637e279b6c1SSam Ravnborg	bool "EISA support"
2638e279b6c1SSam Ravnborg	depends on ISA
2639e279b6c1SSam Ravnborg	---help---
2640e279b6c1SSam Ravnborg	  The Extended Industry Standard Architecture (EISA) bus was
2641e279b6c1SSam Ravnborg	  developed as an open alternative to the IBM MicroChannel bus.
2642e279b6c1SSam Ravnborg
2643e279b6c1SSam Ravnborg	  The EISA bus provided some of the features of the IBM MicroChannel
2644e279b6c1SSam Ravnborg	  bus while maintaining backward compatibility with cards made for
2645e279b6c1SSam Ravnborg	  the older ISA bus.  The EISA bus saw limited use between 1988 and
2646e279b6c1SSam Ravnborg	  1995 when it was made obsolete by the PCI bus.
2647e279b6c1SSam Ravnborg
2648e279b6c1SSam Ravnborg	  Say Y here if you are building a kernel for an EISA-based machine.
2649e279b6c1SSam Ravnborg
2650e279b6c1SSam Ravnborg	  Otherwise, say N.
2651e279b6c1SSam Ravnborg
2652e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig"
2653e279b6c1SSam Ravnborg
2654e279b6c1SSam Ravnborgconfig SCx200
2655e279b6c1SSam Ravnborg	tristate "NatSemi SCx200 support"
26568f9ca475SIngo Molnar	---help---
2657e279b6c1SSam Ravnborg	  This provides basic support for National Semiconductor's
2658e279b6c1SSam Ravnborg	  (now AMD's) Geode processors.  The driver probes for the
2659e279b6c1SSam Ravnborg	  PCI-IDs of several on-chip devices, so its a good dependency
2660e279b6c1SSam Ravnborg	  for other scx200_* drivers.
2661e279b6c1SSam Ravnborg
2662e279b6c1SSam Ravnborg	  If compiled as a module, the driver is named scx200.
2663e279b6c1SSam Ravnborg
2664e279b6c1SSam Ravnborgconfig SCx200HR_TIMER
2665e279b6c1SSam Ravnborg	tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2666592913ecSJohn Stultz	depends on SCx200
2667e279b6c1SSam Ravnborg	default y
26688f9ca475SIngo Molnar	---help---
2669e279b6c1SSam Ravnborg	  This driver provides a clocksource built upon the on-chip
2670e279b6c1SSam Ravnborg	  27MHz high-resolution timer.  Its also a workaround for
2671e279b6c1SSam Ravnborg	  NSC Geode SC-1100's buggy TSC, which loses time when the
2672e279b6c1SSam Ravnborg	  processor goes idle (as is done by the scheduler).  The
2673e279b6c1SSam Ravnborg	  other workaround is idle=poll boot option.
2674e279b6c1SSam Ravnborg
26753ef0e1f8SAndres Salomonconfig OLPC
26763ef0e1f8SAndres Salomon	bool "One Laptop Per Child support"
267754008979SThomas Gleixner	depends on !X86_PAE
26783c554946SAndres Salomon	select GPIOLIB
2679dc3119e7SThomas Gleixner	select OF
268045bb1674SDaniel Drake	select OF_PROMTREE
2681b4e51854SGrant Likely	select IRQ_DOMAIN
26828f9ca475SIngo Molnar	---help---
26833ef0e1f8SAndres Salomon	  Add support for detecting the unique features of the OLPC
26843ef0e1f8SAndres Salomon	  XO hardware.
26853ef0e1f8SAndres Salomon
2686a3128588SDaniel Drakeconfig OLPC_XO1_PM
2687a3128588SDaniel Drake	bool "OLPC XO-1 Power Management"
268897c4cb71SDaniel Drake	depends on OLPC && MFD_CS5535 && PM_SLEEP
2689a3128588SDaniel Drake	select MFD_CORE
2690bf1ebf00SDaniel Drake	---help---
269197c4cb71SDaniel Drake	  Add support for poweroff and suspend of the OLPC XO-1 laptop.
2692bf1ebf00SDaniel Drake
2693cfee9597SDaniel Drakeconfig OLPC_XO1_RTC
2694cfee9597SDaniel Drake	bool "OLPC XO-1 Real Time Clock"
2695cfee9597SDaniel Drake	depends on OLPC_XO1_PM && RTC_DRV_CMOS
2696cfee9597SDaniel Drake	---help---
2697cfee9597SDaniel Drake	  Add support for the XO-1 real time clock, which can be used as a
2698cfee9597SDaniel Drake	  programmable wakeup source.
2699cfee9597SDaniel Drake
27007feda8e9SDaniel Drakeconfig OLPC_XO1_SCI
27017feda8e9SDaniel Drake	bool "OLPC XO-1 SCI extras"
2702d8d01a63SDaniel Drake	depends on OLPC && OLPC_XO1_PM
2703ed8e47feSRandy Dunlap	depends on INPUT=y
2704d8d01a63SDaniel Drake	select POWER_SUPPLY
27057feda8e9SDaniel Drake	select GPIO_CS5535
27067feda8e9SDaniel Drake	select MFD_CORE
27077feda8e9SDaniel Drake	---help---
27087feda8e9SDaniel Drake	  Add support for SCI-based features of the OLPC XO-1 laptop:
27097bc74b3dSDaniel Drake	   - EC-driven system wakeups
27107feda8e9SDaniel Drake	   - Power button
27117bc74b3dSDaniel Drake	   - Ebook switch
27122cf2baeaSDaniel Drake	   - Lid switch
2713e1040ac6SDaniel Drake	   - AC adapter status updates
2714e1040ac6SDaniel Drake	   - Battery status updates
27157feda8e9SDaniel Drake
2716a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI
2717a0f30f59SDaniel Drake	bool "OLPC XO-1.5 SCI extras"
2718d8d01a63SDaniel Drake	depends on OLPC && ACPI
2719d8d01a63SDaniel Drake	select POWER_SUPPLY
2720a0f30f59SDaniel Drake	---help---
2721a0f30f59SDaniel Drake	  Add support for SCI-based features of the OLPC XO-1.5 laptop:
2722a0f30f59SDaniel Drake	   - EC-driven system wakeups
2723a0f30f59SDaniel Drake	   - AC adapter status updates
2724a0f30f59SDaniel Drake	   - Battery status updates
2725e279b6c1SSam Ravnborg
2726d4f3e350SEd Wildgooseconfig ALIX
2727d4f3e350SEd Wildgoose	bool "PCEngines ALIX System Support (LED setup)"
2728d4f3e350SEd Wildgoose	select GPIOLIB
2729d4f3e350SEd Wildgoose	---help---
2730d4f3e350SEd Wildgoose	  This option enables system support for the PCEngines ALIX.
2731d4f3e350SEd Wildgoose	  At present this just sets up LEDs for GPIO control on
2732d4f3e350SEd Wildgoose	  ALIX2/3/6 boards.  However, other system specific setup should
2733d4f3e350SEd Wildgoose	  get added here.
2734d4f3e350SEd Wildgoose
2735d4f3e350SEd Wildgoose	  Note: You must still enable the drivers for GPIO and LED support
2736d4f3e350SEd Wildgoose	  (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2737d4f3e350SEd Wildgoose
2738d4f3e350SEd Wildgoose	  Note: You have to set alix.force=1 for boards with Award BIOS.
2739d4f3e350SEd Wildgoose
2740da4e3302SPhilip Prindevilleconfig NET5501
2741da4e3302SPhilip Prindeville	bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2742da4e3302SPhilip Prindeville	select GPIOLIB
2743da4e3302SPhilip Prindeville	---help---
2744da4e3302SPhilip Prindeville	  This option enables system support for the Soekris Engineering net5501.
2745da4e3302SPhilip Prindeville
27463197059aSPhilip A. Prindevilleconfig GEOS
27473197059aSPhilip A. Prindeville	bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
27483197059aSPhilip A. Prindeville	select GPIOLIB
27493197059aSPhilip A. Prindeville	depends on DMI
27503197059aSPhilip A. Prindeville	---help---
27513197059aSPhilip A. Prindeville	  This option enables system support for the Traverse Technologies GEOS.
27523197059aSPhilip A. Prindeville
27537d029125SVivien Didelotconfig TS5500
27547d029125SVivien Didelot	bool "Technologic Systems TS-5500 platform support"
27557d029125SVivien Didelot	depends on MELAN
27567d029125SVivien Didelot	select CHECK_SIGNATURE
27577d029125SVivien Didelot	select NEW_LEDS
27587d029125SVivien Didelot	select LEDS_CLASS
27597d029125SVivien Didelot	---help---
27607d029125SVivien Didelot	  This option enables system support for the Technologic Systems TS-5500.
27617d029125SVivien Didelot
2762e279b6c1SSam Ravnborgendif # X86_32
2763e279b6c1SSam Ravnborg
276423ac4ae8SAndreas Herrmannconfig AMD_NB
2765e279b6c1SSam Ravnborg	def_bool y
27660e152cd7SBorislav Petkov	depends on CPU_SUP_AMD && PCI
2767e279b6c1SSam Ravnborg
2768e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig"
2769e279b6c1SSam Ravnborg
2770388b78adSAlexandre Bounineconfig RAPIDIO
2771fdf90abcSAlexandre Bounine	tristate "RapidIO support"
2772388b78adSAlexandre Bounine	depends on PCI
2773388b78adSAlexandre Bounine	default n
2774388b78adSAlexandre Bounine	help
2775fdf90abcSAlexandre Bounine	  If enabled this option will include drivers and the core
2776388b78adSAlexandre Bounine	  infrastructure code to support RapidIO interconnect devices.
2777388b78adSAlexandre Bounine
2778388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig"
2779388b78adSAlexandre Bounine
2780e3263ab3SDavid Herrmannconfig X86_SYSFB
2781e3263ab3SDavid Herrmann	bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2782e3263ab3SDavid Herrmann	help
2783e3263ab3SDavid Herrmann	  Firmwares often provide initial graphics framebuffers so the BIOS,
2784e3263ab3SDavid Herrmann	  bootloader or kernel can show basic video-output during boot for
2785e3263ab3SDavid Herrmann	  user-guidance and debugging. Historically, x86 used the VESA BIOS
2786e3263ab3SDavid Herrmann	  Extensions and EFI-framebuffers for this, which are mostly limited
2787e3263ab3SDavid Herrmann	  to x86.
2788e3263ab3SDavid Herrmann	  This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2789e3263ab3SDavid Herrmann	  framebuffers so the new generic system-framebuffer drivers can be
2790e3263ab3SDavid Herrmann	  used on x86. If the framebuffer is not compatible with the generic
2791e3263ab3SDavid Herrmann	  modes, it is adverticed as fallback platform framebuffer so legacy
2792e3263ab3SDavid Herrmann	  drivers like efifb, vesafb and uvesafb can pick it up.
2793e3263ab3SDavid Herrmann	  If this option is not selected, all system framebuffers are always
2794e3263ab3SDavid Herrmann	  marked as fallback platform framebuffers as usual.
2795e3263ab3SDavid Herrmann
2796e3263ab3SDavid Herrmann	  Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2797e3263ab3SDavid Herrmann	  not be able to pick up generic system framebuffers if this option
2798e3263ab3SDavid Herrmann	  is selected. You are highly encouraged to enable simplefb as
2799e3263ab3SDavid Herrmann	  replacement if you select this option. simplefb can correctly deal
2800e3263ab3SDavid Herrmann	  with generic system framebuffers. But you should still keep vesafb
2801e3263ab3SDavid Herrmann	  and others enabled as fallback if a system framebuffer is
2802e3263ab3SDavid Herrmann	  incompatible with simplefb.
2803e3263ab3SDavid Herrmann
2804e3263ab3SDavid Herrmann	  If unsure, say Y.
2805e3263ab3SDavid Herrmann
2806e279b6c1SSam Ravnborgendmenu
2807e279b6c1SSam Ravnborg
2808e279b6c1SSam Ravnborg
2809e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations"
2810e279b6c1SSam Ravnborg
2811e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt"
2812e279b6c1SSam Ravnborg
2813e279b6c1SSam Ravnborgconfig IA32_EMULATION
2814e279b6c1SSam Ravnborg	bool "IA32 Emulation"
2815e279b6c1SSam Ravnborg	depends on X86_64
281639f88911SIngo Molnar	select ARCH_WANT_OLD_COMPAT_IPC
2817d1603990SRandy Dunlap	select BINFMT_ELF
2818a97f52e6SRoland McGrath	select COMPAT_BINFMT_ELF
281939f88911SIngo Molnar	select COMPAT_OLD_SIGACTION
28208f9ca475SIngo Molnar	---help---
28215fd92e65SH. J. Lu	  Include code to run legacy 32-bit programs under a
28225fd92e65SH. J. Lu	  64-bit kernel. You should likely turn this on, unless you're
28235fd92e65SH. J. Lu	  100% sure that you don't have any 32-bit programs left.
2824e279b6c1SSam Ravnborg
2825e279b6c1SSam Ravnborgconfig IA32_AOUT
2826e279b6c1SSam Ravnborg	tristate "IA32 a.out support"
28276b213e1bSDavid Woodhouse	depends on IA32_EMULATION
28288f9ca475SIngo Molnar	---help---
2829e279b6c1SSam Ravnborg	  Support old a.out binaries in the 32bit emulation.
2830e279b6c1SSam Ravnborg
28310bf62763SH. Peter Anvinconfig X86_X32
28326ea30386SKees Cook	bool "x32 ABI for 64-bit mode"
28339b54050bSBrian Gerst	depends on X86_64
28345fd92e65SH. J. Lu	---help---
28355fd92e65SH. J. Lu	  Include code to run binaries for the x32 native 32-bit ABI
28365fd92e65SH. J. Lu	  for 64-bit processors.  An x32 process gets access to the
28375fd92e65SH. J. Lu	  full 64-bit register file and wide data path while leaving
28385fd92e65SH. J. Lu	  pointers at 32 bits for smaller memory footprint.
28395fd92e65SH. J. Lu
28405fd92e65SH. J. Lu	  You will need a recent binutils (2.22 or later) with
28415fd92e65SH. J. Lu	  elf32_x86_64 support enabled to compile a kernel with this
28425fd92e65SH. J. Lu	  option set.
28435fd92e65SH. J. Lu
2844953fee1dSIngo Molnarconfig COMPAT_32
2845953fee1dSIngo Molnar	def_bool y
2846953fee1dSIngo Molnar	depends on IA32_EMULATION || X86_32
2847953fee1dSIngo Molnar	select HAVE_UID16
2848953fee1dSIngo Molnar	select OLD_SIGSUSPEND3
2849953fee1dSIngo Molnar
2850e279b6c1SSam Ravnborgconfig COMPAT
28513c2362e6SHarvey Harrison	def_bool y
28520bf62763SH. Peter Anvin	depends on IA32_EMULATION || X86_X32
2853e279b6c1SSam Ravnborg
28543120e25eSJan Beulichif COMPAT
2855e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT
28563120e25eSJan Beulich	def_bool y
2857e279b6c1SSam Ravnborg
2858e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT
28593c2362e6SHarvey Harrison	def_bool y
28603120e25eSJan Beulich	depends on SYSVIPC
28613120e25eSJan Beulichendif
2862ee009e4aSDavid Howells
2863e279b6c1SSam Ravnborgendmenu
2864e279b6c1SSam Ravnborg
2865e279b6c1SSam Ravnborg
2866e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP
2867e5beae16SKeith Packard	def_bool y
2868e5beae16SKeith Packard	depends on X86_32
2869e5beae16SKeith Packard
28704692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS
28714692d77fSAlessandro Rubini	bool
287283125a3aSAlessandro Rubini	depends on X86_64 || STA2X11
28734692d77fSAlessandro Rubini
2874f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP
2875f7219a53SAlessandro Rubini	bool
287683125a3aSAlessandro Rubini	depends on STA2X11
2877f7219a53SAlessandro Rubini
2878e585513bSKirill A. Shutemovconfig HAVE_GENERIC_GUP
2879e585513bSKirill A. Shutemov	def_bool y
2880e585513bSKirill A. Shutemov
2881e279b6c1SSam Ravnborgsource "net/Kconfig"
2882e279b6c1SSam Ravnborg
2883e279b6c1SSam Ravnborgsource "drivers/Kconfig"
2884e279b6c1SSam Ravnborg
2885e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig"
2886e279b6c1SSam Ravnborg
2887e279b6c1SSam Ravnborgsource "fs/Kconfig"
2888e279b6c1SSam Ravnborg
2889e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug"
2890e279b6c1SSam Ravnborg
2891e279b6c1SSam Ravnborgsource "security/Kconfig"
2892e279b6c1SSam Ravnborg
2893e279b6c1SSam Ravnborgsource "crypto/Kconfig"
2894e279b6c1SSam Ravnborg
2895edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig"
2896edf88417SAvi Kivity
2897e279b6c1SSam Ravnborgsource "lib/Kconfig"
2898