xref: /linux/arch/x86/Kconfig (revision ac1ab12a3e6e878274e7107c8c6f326694a1c1f3)
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
5839208aa7SKees Cook	select ARCH_HAS_REFCOUNT
590aed55afSDan Williams	select ARCH_HAS_UACCESS_FLUSHCACHE	if X86_64
60d2852a22SDaniel Borkmann	select ARCH_HAS_SET_MEMORY
616471b825SIngo Molnar	select ARCH_HAS_SG_CHAIN
62ad21fc4fSLaura Abbott	select ARCH_HAS_STRICT_KERNEL_RWX
63ad21fc4fSLaura Abbott	select ARCH_HAS_STRICT_MODULE_RWX
64*ac1ab12aSMathieu Desnoyers	select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
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
970fa115daSThomas Gleixner	select GENERIC_IRQ_MATRIX_ALLOCATOR	if X86_LOCAL_APIC
98ad7a929fSThomas Gleixner	select GENERIC_IRQ_MIGRATION		if SMP
996471b825SIngo Molnar	select GENERIC_IRQ_PROBE
100c201c917SThomas Gleixner	select GENERIC_IRQ_RESERVATION_MODE
1016471b825SIngo Molnar	select GENERIC_IRQ_SHOW
1026471b825SIngo Molnar	select GENERIC_PENDING_IRQ		if SMP
1036471b825SIngo Molnar	select GENERIC_SMP_IDLE_THREAD
1046471b825SIngo Molnar	select GENERIC_STRNCPY_FROM_USER
1056471b825SIngo Molnar	select GENERIC_STRNLEN_USER
1066471b825SIngo Molnar	select GENERIC_TIME_VSYSCALL
1077edaeb68SThomas Gleixner	select HARDLOCKUP_CHECK_TIMESTAMP	if X86_64
1086471b825SIngo Molnar	select HAVE_ACPI_APEI			if ACPI
1096471b825SIngo Molnar	select HAVE_ACPI_APEI_NMI		if ACPI
1106471b825SIngo Molnar	select HAVE_ALIGNED_STRUCT_PAGE		if SLUB
1116471b825SIngo Molnar	select HAVE_ARCH_AUDITSYSCALL
1126471b825SIngo Molnar	select HAVE_ARCH_HUGE_VMAP		if X86_64 || X86_PAE
1136471b825SIngo Molnar	select HAVE_ARCH_JUMP_LABEL
114d17a1d97SAndrey Ryabinin	select HAVE_ARCH_KASAN			if X86_64
1156471b825SIngo Molnar	select HAVE_ARCH_KGDB
1169e08f57dSDaniel Cashman	select HAVE_ARCH_MMAP_RND_BITS		if MMU
1179e08f57dSDaniel Cashman	select HAVE_ARCH_MMAP_RND_COMPAT_BITS	if MMU && COMPAT
1181b028f78SDmitry Safonov	select HAVE_ARCH_COMPAT_MMAP_BASES	if MMU && COMPAT
1196471b825SIngo Molnar	select HAVE_ARCH_SECCOMP_FILTER
1206471b825SIngo Molnar	select HAVE_ARCH_TRACEHOOK
1216471b825SIngo Molnar	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
122a00cc7d9SMatthew Wilcox	select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
123e37e43a4SAndy Lutomirski	select HAVE_ARCH_VMAP_STACK		if X86_64
124c763ea26SIngo Molnar	select HAVE_ARCH_WITHIN_STACK_FRAMES
1256471b825SIngo Molnar	select HAVE_CC_STACKPROTECTOR
1266471b825SIngo Molnar	select HAVE_CMPXCHG_DOUBLE
1276471b825SIngo Molnar	select HAVE_CMPXCHG_LOCAL
1286471b825SIngo Molnar	select HAVE_CONTEXT_TRACKING		if X86_64
129c1bd55f9SJosh Triplett	select HAVE_COPY_THREAD_TLS
1306471b825SIngo Molnar	select HAVE_C_RECORDMCOUNT
1316471b825SIngo Molnar	select HAVE_DEBUG_KMEMLEAK
1326471b825SIngo Molnar	select HAVE_DEBUG_STACKOVERFLOW
1336471b825SIngo Molnar	select HAVE_DMA_API_DEBUG
1349c5a3621SAkinobu Mita	select HAVE_DMA_CONTIGUOUS
135677aa9f7SSteven Rostedt	select HAVE_DYNAMIC_FTRACE
13606aeaaeaSMasami Hiramatsu	select HAVE_DYNAMIC_FTRACE_WITH_REGS
137c763ea26SIngo Molnar	select HAVE_EBPF_JIT			if X86_64
13858340a07SJohannes Berg	select HAVE_EFFICIENT_UNALIGNED_ACCESS
1395f56a5dfSJiri Slaby	select HAVE_EXIT_THREAD
140644e0e8dSSteven Rostedt (VMware)	select HAVE_FENTRY			if X86_64 || DYNAMIC_FTRACE
1416471b825SIngo Molnar	select HAVE_FTRACE_MCOUNT_RECORD
1426471b825SIngo Molnar	select HAVE_FUNCTION_GRAPH_TRACER
1436471b825SIngo Molnar	select HAVE_FUNCTION_TRACER
1446b90bd4bSEmese Revfy	select HAVE_GCC_PLUGINS
1450067f129SK.Prasad	select HAVE_HW_BREAKPOINT
1466471b825SIngo Molnar	select HAVE_IDE
1476471b825SIngo Molnar	select HAVE_IOREMAP_PROT
1486471b825SIngo Molnar	select HAVE_IRQ_EXIT_ON_IRQ_STACK	if X86_64
1496471b825SIngo Molnar	select HAVE_IRQ_TIME_ACCOUNTING
1506471b825SIngo Molnar	select HAVE_KERNEL_BZIP2
1516471b825SIngo Molnar	select HAVE_KERNEL_GZIP
1526471b825SIngo Molnar	select HAVE_KERNEL_LZ4
1536471b825SIngo Molnar	select HAVE_KERNEL_LZMA
1546471b825SIngo Molnar	select HAVE_KERNEL_LZO
1556471b825SIngo Molnar	select HAVE_KERNEL_XZ
1566471b825SIngo Molnar	select HAVE_KPROBES
1576471b825SIngo Molnar	select HAVE_KPROBES_ON_FTRACE
1586471b825SIngo Molnar	select HAVE_KRETPROBES
1596471b825SIngo Molnar	select HAVE_KVM
1606471b825SIngo Molnar	select HAVE_LIVEPATCH			if X86_64
1616471b825SIngo Molnar	select HAVE_MEMBLOCK
1626471b825SIngo Molnar	select HAVE_MEMBLOCK_NODE_MAP
1630102752eSFrederic Weisbecker	select HAVE_MIXED_BREAKPOINTS_REGS
164ee9f8fceSJosh Poimboeuf	select HAVE_MOD_ARCH_SPECIFIC
16542a0bb3fSPetr Mladek	select HAVE_NMI
1666471b825SIngo Molnar	select HAVE_OPROFILE
1676471b825SIngo Molnar	select HAVE_OPTPROBES
1686471b825SIngo Molnar	select HAVE_PCSPKR_PLATFORM
1696471b825SIngo Molnar	select HAVE_PERF_EVENTS
170c01d4323SFrederic Weisbecker	select HAVE_PERF_EVENTS_NMI
17192e5aae4SNicholas Piggin	select HAVE_HARDLOCKUP_DETECTOR_PERF	if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
172c5e63197SJiri Olsa	select HAVE_PERF_REGS
173c5ebcedbSJiri Olsa	select HAVE_PERF_USER_STACK_DUMP
1749e52fc2bSVitaly Kuznetsov	select HAVE_RCU_TABLE_FREE
1756471b825SIngo Molnar	select HAVE_REGS_AND_STACK_ACCESS_API
17611af8474SJosh Poimboeuf	select HAVE_RELIABLE_STACKTRACE		if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
177c763ea26SIngo Molnar	select HAVE_STACK_VALIDATION		if X86_64
1786471b825SIngo Molnar	select HAVE_SYSCALL_TRACEPOINTS
1796471b825SIngo Molnar	select HAVE_UNSTABLE_SCHED_CLOCK
1807c68af6eSAvi Kivity	select HAVE_USER_RETURN_NOTIFIER
181c0185808SThomas Gleixner	select IRQ_FORCED_THREADING
182df65c1bcSThomas Gleixner	select PCI_LOCKLESS_CONFIG
1836471b825SIngo Molnar	select PERF_EVENTS
1843195ef59SPrarit Bhargava	select RTC_LIB
185d6faca40SArnd Bergmann	select RTC_MC146818_LIB
1866471b825SIngo Molnar	select SPARSE_IRQ
18783fe27eaSPranith Kumar	select SRCU
1886471b825SIngo Molnar	select SYSCTL_EXCEPTION_TRACE
18915f4eae7SAndy Lutomirski	select THREAD_INFO_IN_TASK
1906471b825SIngo Molnar	select USER_STACKTRACE_SUPPORT
1916471b825SIngo Molnar	select VIRT_TO_BUS
1926471b825SIngo Molnar	select X86_FEATURE_NAMES		if PROC_FS
1937d8330a5SBalbir Singh
194ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER
1953120e25eSJan Beulich	def_bool y
1963120e25eSJan Beulich	depends on KPROBES || PERF_EVENTS || UPROBES
197ba7e4d13SIngo Molnar
19851b26adaSLinus Torvaldsconfig OUTPUT_FORMAT
19951b26adaSLinus Torvalds	string
20051b26adaSLinus Torvalds	default "elf32-i386" if X86_32
20151b26adaSLinus Torvalds	default "elf64-x86-64" if X86_64
20251b26adaSLinus Torvalds
20373531905SSam Ravnborgconfig ARCH_DEFCONFIG
204b9b39bfbSSam Ravnborg	string
20573531905SSam Ravnborg	default "arch/x86/configs/i386_defconfig" if X86_32
20673531905SSam Ravnborg	default "arch/x86/configs/x86_64_defconfig" if X86_64
207b9b39bfbSSam Ravnborg
2088d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT
2093c2362e6SHarvey Harrison	def_bool y
2108d5fffb9SSam Ravnborg
2118d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT
2123c2362e6SHarvey Harrison	def_bool y
2138d5fffb9SSam Ravnborg
2148d5fffb9SSam Ravnborgconfig MMU
2153c2362e6SHarvey Harrison	def_bool y
2168d5fffb9SSam Ravnborg
2179e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN
2189e08f57dSDaniel Cashman	default 28 if 64BIT
2199e08f57dSDaniel Cashman	default 8
2209e08f57dSDaniel Cashman
2219e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX
2229e08f57dSDaniel Cashman	default 32 if 64BIT
2239e08f57dSDaniel Cashman	default 16
2249e08f57dSDaniel Cashman
2259e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN
2269e08f57dSDaniel Cashman	default 8
2279e08f57dSDaniel Cashman
2289e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX
2299e08f57dSDaniel Cashman	default 16
2309e08f57dSDaniel Cashman
2318d5fffb9SSam Ravnborgconfig SBUS
2328d5fffb9SSam Ravnborg	bool
2338d5fffb9SSam Ravnborg
2343bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE
2353120e25eSJan Beulich	def_bool y
236a6dfa128SKonrad Rzeszutek Wilk	depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
2373bc4e459SFUJITA Tomonori
23818e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH
2394a14d84eSAndrew Morton	def_bool y
24018e98307SFUJITA Tomonori
2418d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA
2423120e25eSJan Beulich	def_bool y
2433120e25eSJan Beulich	depends on ISA_DMA_API
2448d5fffb9SSam Ravnborg
2458d5fffb9SSam Ravnborgconfig GENERIC_BUG
2463c2362e6SHarvey Harrison	def_bool y
2478d5fffb9SSam Ravnborg	depends on BUG
248b93a531eSJan Beulich	select GENERIC_BUG_RELATIVE_POINTERS if X86_64
249b93a531eSJan Beulich
250b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS
251b93a531eSJan Beulich	bool
2528d5fffb9SSam Ravnborg
2538d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT
2543c2362e6SHarvey Harrison	def_bool y
2558d5fffb9SSam Ravnborg
2568d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC
2573120e25eSJan Beulich	def_bool y
2583120e25eSJan Beulich	depends on ISA_DMA_API
2598d5fffb9SSam Ravnborg
2601032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM
2613120e25eSJan Beulich	def_bool y
2621032c0baSSam Ravnborg
2631032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY
2641032c0baSSam Ravnborg	def_bool y
2651032c0baSSam Ravnborg
2669a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX
2679a0b8415Svenkatesh.pallipadi@intel.com	def_bool y
2688d5fffb9SSam Ravnborg
2691b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE
2701b27d05bSPekka Enberg	def_bool y
2711b27d05bSPekka Enberg
272dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA
27389c9c4c5SBrian Gerst	def_bool y
274b32ef636Stravis@sgi.com
27508fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK
27608fc4580STejun Heo	def_bool y
27708fc4580STejun Heo
27808fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK
27911124411STejun Heo	def_bool y
28011124411STejun Heo
281801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE
282801e4062SJohannes Berg	def_bool y
283801e4062SJohannes Berg
284f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE
285f4cb5700SJohannes Berg	def_bool y
286f4cb5700SJohannes Berg
287cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE
288cfe28c5dSSteve Capper	def_bool y
289cfe28c5dSSteve Capper
29053313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB
29153313b2cSSteve Capper	def_bool y
29253313b2cSSteve Capper
2938d5fffb9SSam Ravnborgconfig ZONE_DMA32
294e0fd24a3SJan Beulich	def_bool y if X86_64
2958d5fffb9SSam Ravnborg
2968d5fffb9SSam Ravnborgconfig AUDIT_ARCH
297e0fd24a3SJan Beulich	def_bool y if X86_64
2988d5fffb9SSam Ravnborg
299765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING
300765c68bdSIngo Molnar	def_bool y
301765c68bdSIngo Molnar
3026a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC
3036a11f75bSAkinobu Mita	def_bool y
3046a11f75bSAkinobu Mita
305d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET
306d6f2d75aSAndrey Ryabinin	hex
307d6f2d75aSAndrey Ryabinin	depends on KASAN
308d6f2d75aSAndrey Ryabinin	default 0xdffffc0000000000
309d6f2d75aSAndrey Ryabinin
31069575d38SShane Wangconfig HAVE_INTEL_TXT
31169575d38SShane Wang	def_bool y
3126ea30386SKees Cook	depends on INTEL_IOMMU && ACPI
31369575d38SShane Wang
3146b0c3d44SSam Ravnborgconfig X86_32_SMP
3156b0c3d44SSam Ravnborg	def_bool y
3166b0c3d44SSam Ravnborg	depends on X86_32 && SMP
3176b0c3d44SSam Ravnborg
3186b0c3d44SSam Ravnborgconfig X86_64_SMP
3196b0c3d44SSam Ravnborg	def_bool y
3206b0c3d44SSam Ravnborg	depends on X86_64 && SMP
3216b0c3d44SSam Ravnborg
322ccbeed3aSTejun Heoconfig X86_32_LAZY_GS
323ccbeed3aSTejun Heo	def_bool y
32460a5317fSTejun Heo	depends on X86_32 && !CC_STACKPROTECTOR
325ccbeed3aSTejun Heo
3262b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES
3272b144498SSrikar Dronamraju	def_bool y
3282b144498SSrikar Dronamraju
329d20642f0SRob Herringconfig FIX_EARLYCON_MEM
330d20642f0SRob Herring	def_bool y
331d20642f0SRob Herring
33298233368SKirill A. Shutemovconfig PGTABLE_LEVELS
33398233368SKirill A. Shutemov	int
33477ef56e4SKirill A. Shutemov	default 5 if X86_5LEVEL
33598233368SKirill A. Shutemov	default 4 if X86_64
33698233368SKirill A. Shutemov	default 3 if X86_PAE
33798233368SKirill A. Shutemov	default 2
33898233368SKirill A. Shutemov
339506f1d07SSam Ravnborgsource "init/Kconfig"
340dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer"
3418d5fffb9SSam Ravnborg
342506f1d07SSam Ravnborgmenu "Processor type and features"
343506f1d07SSam Ravnborg
3445ee71535SRandy Dunlapconfig ZONE_DMA
3455ee71535SRandy Dunlap	bool "DMA memory allocation support" if EXPERT
3465ee71535SRandy Dunlap	default y
3475ee71535SRandy Dunlap	help
3485ee71535SRandy Dunlap	  DMA memory allocation support allows devices with less than 32-bit
3495ee71535SRandy Dunlap	  addressing to allocate within the first 16MB of address space.
3505ee71535SRandy Dunlap	  Disable if no such devices will be used.
3515ee71535SRandy Dunlap
3525ee71535SRandy Dunlap	  If unsure, say Y.
3535ee71535SRandy Dunlap
354506f1d07SSam Ravnborgconfig SMP
355506f1d07SSam Ravnborg	bool "Symmetric multi-processing support"
356506f1d07SSam Ravnborg	---help---
357506f1d07SSam Ravnborg	  This enables support for systems with more than one CPU. If you have
3584a474157SRobert Graffham	  a system with only one CPU, say N. If you have a system with more
3594a474157SRobert Graffham	  than one CPU, say Y.
360506f1d07SSam Ravnborg
3614a474157SRobert Graffham	  If you say N here, the kernel will run on uni- and multiprocessor
362506f1d07SSam Ravnborg	  machines, but will use only one CPU of a multiprocessor machine. If
363506f1d07SSam Ravnborg	  you say Y here, the kernel will run on many, but not all,
3644a474157SRobert Graffham	  uniprocessor machines. On a uniprocessor machine, the kernel
365506f1d07SSam Ravnborg	  will run faster if you say N here.
366506f1d07SSam Ravnborg
367506f1d07SSam Ravnborg	  Note that if you say Y here and choose architecture "586" or
368506f1d07SSam Ravnborg	  "Pentium" under "Processor family", the kernel will not work on 486
369506f1d07SSam Ravnborg	  architectures. Similarly, multiprocessor kernels for the "PPro"
370506f1d07SSam Ravnborg	  architecture may not work on all Pentium based boards.
371506f1d07SSam Ravnborg
372506f1d07SSam Ravnborg	  People using multiprocessor machines who say Y here should also say
373506f1d07SSam Ravnborg	  Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
374506f1d07SSam Ravnborg	  Management" code will be disabled if you say Y here.
375506f1d07SSam Ravnborg
376395cf969SPaul Bolle	  See also <file:Documentation/x86/i386/IO-APIC.txt>,
377c9525a3fSBenjamin Peterson	  <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
378506f1d07SSam Ravnborg	  <http://www.tldp.org/docs.html#howto>.
379506f1d07SSam Ravnborg
380506f1d07SSam Ravnborg	  If you don't know what to do here, say N.
381506f1d07SSam Ravnborg
3829def39beSJosh Triplettconfig X86_FEATURE_NAMES
3839def39beSJosh Triplett	bool "Processor feature human-readable names" if EMBEDDED
3849def39beSJosh Triplett	default y
3859def39beSJosh Triplett	---help---
3869def39beSJosh Triplett	  This option compiles in a table of x86 feature bits and corresponding
3879def39beSJosh Triplett	  names.  This is required to support /proc/cpuinfo and a few kernel
3889def39beSJosh Triplett	  messages.  You can disable this to save space, at the expense of
3899def39beSJosh Triplett	  making those few kernel messages show numeric feature bits instead.
3909def39beSJosh Triplett
3919def39beSJosh Triplett	  If in doubt, say Y.
3929def39beSJosh Triplett
3936e1315feSBorislav Petkovconfig X86_FAST_FEATURE_TESTS
3946e1315feSBorislav Petkov	bool "Fast CPU feature tests" if EMBEDDED
3956e1315feSBorislav Petkov	default y
3966e1315feSBorislav Petkov	---help---
3976e1315feSBorislav Petkov	  Some fast-paths in the kernel depend on the capabilities of the CPU.
3986e1315feSBorislav Petkov	  Say Y here for the kernel to patch in the appropriate code at runtime
3996e1315feSBorislav Petkov	  based on the capabilities of the CPU. The infrastructure for patching
4006e1315feSBorislav Petkov	  code at runtime takes up some additional space; space-constrained
4016e1315feSBorislav Petkov	  embedded systems may wish to say N here to produce smaller, slightly
4026e1315feSBorislav Petkov	  slower code.
4036e1315feSBorislav Petkov
40406cd9a7dSYinghai Luconfig X86_X2APIC
40506cd9a7dSYinghai Lu	bool "Support x2apic"
40619e3d60dSJan Kiszka	depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
40706cd9a7dSYinghai Lu	---help---
40806cd9a7dSYinghai Lu	  This enables x2apic support on CPUs that have this feature.
40906cd9a7dSYinghai Lu
41006cd9a7dSYinghai Lu	  This allows 32-bit apic IDs (so it can support very large systems),
41106cd9a7dSYinghai Lu	  and accesses the local apic via MSRs not via mmio.
41206cd9a7dSYinghai Lu
41306cd9a7dSYinghai Lu	  If you don't know what to do here, say N.
41406cd9a7dSYinghai Lu
4156695c85bSYinghai Luconfig X86_MPPARSE
4166e87f9b7SBin Gao	bool "Enable MPS table" if ACPI || SFI
4177a527688SJan Beulich	default y
4185ab74722SIngo Molnar	depends on X86_LOCAL_APIC
4198f9ca475SIngo Molnar	---help---
4206695c85bSYinghai Lu	  For old smp systems that do not have proper acpi support. Newer systems
4216695c85bSYinghai Lu	  (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
4226695c85bSYinghai Lu
42326f7ef14SYinghai Luconfig X86_BIGSMP
42426f7ef14SYinghai Lu	bool "Support for big SMP systems with more than 8 CPUs"
42526f7ef14SYinghai Lu	depends on X86_32 && SMP
4268f9ca475SIngo Molnar	---help---
42726f7ef14SYinghai Lu	  This option is needed for the systems that have more than 8 CPUs
428506f1d07SSam Ravnborg
429ddd70cf9SJun Nakajimaconfig GOLDFISH
430ddd70cf9SJun Nakajima       def_bool y
431ddd70cf9SJun Nakajima       depends on X86_GOLDFISH
432ddd70cf9SJun Nakajima
43376b04384SDavid Woodhouseconfig RETPOLINE
43476b04384SDavid Woodhouse	bool "Avoid speculative indirect branches in kernel"
43576b04384SDavid Woodhouse	default y
43676b04384SDavid Woodhouse	help
43776b04384SDavid Woodhouse	  Compile kernel with the retpoline compiler options to guard against
43876b04384SDavid Woodhouse	  kernel-to-user data leaks by avoiding speculative indirect
43976b04384SDavid Woodhouse	  branches. Requires a compiler with -mindirect-branch=thunk-extern
44076b04384SDavid Woodhouse	  support for full protection. The kernel may run slower.
44176b04384SDavid Woodhouse
44276b04384SDavid Woodhouse	  Without compiler support, at least indirect branches in assembler
44376b04384SDavid Woodhouse	  code are eliminated. Since this includes the syscall entry path,
44476b04384SDavid Woodhouse	  it is not entirely pointless.
44576b04384SDavid Woodhouse
446f01d7d51SVikas Shivappaconfig INTEL_RDT
447f01d7d51SVikas Shivappa	bool "Intel Resource Director Technology support"
44878e99b4aSFenghua Yu	default n
44978e99b4aSFenghua Yu	depends on X86 && CPU_SUP_INTEL
45059fe5a77SThomas Gleixner	select KERNFS
45178e99b4aSFenghua Yu	help
452f01d7d51SVikas Shivappa	  Select to enable resource allocation and monitoring which are
453f01d7d51SVikas Shivappa	  sub-features of Intel Resource Director Technology(RDT). More
454f01d7d51SVikas Shivappa	  information about RDT can be found in the Intel x86
455f01d7d51SVikas Shivappa	  Architecture Software Developer Manual.
45678e99b4aSFenghua Yu
45778e99b4aSFenghua Yu	  Say N if unsure.
45878e99b4aSFenghua Yu
4598425091fSRavikiran G Thirumalaiif X86_32
460c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM
461c5c606d9SRavikiran G Thirumalai	bool "Support for extended (non-PC) x86 platforms"
462c5c606d9SRavikiran G Thirumalai	default y
4638f9ca475SIngo Molnar	---help---
46406ac8346SIngo Molnar	  If you disable this option then the kernel will only support
46506ac8346SIngo Molnar	  standard PC platforms. (which covers the vast majority of
46606ac8346SIngo Molnar	  systems out there.)
46706ac8346SIngo Molnar
4688425091fSRavikiran G Thirumalai	  If you enable this option then you'll be able to select support
4698425091fSRavikiran G Thirumalai	  for the following (non-PC) 32 bit x86 platforms:
470cb7b8023SBen Hutchings		Goldfish (Android emulator)
4718425091fSRavikiran G Thirumalai		AMD Elan
4728425091fSRavikiran G Thirumalai		RDC R-321x SoC
4738425091fSRavikiran G Thirumalai		SGI 320/540 (Visual Workstation)
47483125a3aSAlessandro Rubini		STA2X11-based (e.g. Northville)
4753f4110a4SThomas Gleixner		Moorestown MID devices
47606ac8346SIngo Molnar
47706ac8346SIngo Molnar	  If you have one of these systems, or if you want to build a
47806ac8346SIngo Molnar	  generic distribution kernel, say Y here - otherwise say N.
4798425091fSRavikiran G Thirumalaiendif
48006ac8346SIngo Molnar
4818425091fSRavikiran G Thirumalaiif X86_64
4828425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM
4838425091fSRavikiran G Thirumalai	bool "Support for extended (non-PC) x86 platforms"
4848425091fSRavikiran G Thirumalai	default y
4858425091fSRavikiran G Thirumalai	---help---
4868425091fSRavikiran G Thirumalai	  If you disable this option then the kernel will only support
4878425091fSRavikiran G Thirumalai	  standard PC platforms. (which covers the vast majority of
4888425091fSRavikiran G Thirumalai	  systems out there.)
4898425091fSRavikiran G Thirumalai
4908425091fSRavikiran G Thirumalai	  If you enable this option then you'll be able to select support
4918425091fSRavikiran G Thirumalai	  for the following (non-PC) 64 bit x86 platforms:
49244b111b5SSteffen Persvold		Numascale NumaChip
4938425091fSRavikiran G Thirumalai		ScaleMP vSMP
4948425091fSRavikiran G Thirumalai		SGI Ultraviolet
4958425091fSRavikiran G Thirumalai
4968425091fSRavikiran G Thirumalai	  If you have one of these systems, or if you want to build a
4978425091fSRavikiran G Thirumalai	  generic distribution kernel, say Y here - otherwise say N.
4988425091fSRavikiran G Thirumalaiendif
499c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms
500c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions
50144b111b5SSteffen Persvoldconfig X86_NUMACHIP
50244b111b5SSteffen Persvold	bool "Numascale NumaChip"
50344b111b5SSteffen Persvold	depends on X86_64
50444b111b5SSteffen Persvold	depends on X86_EXTENDED_PLATFORM
50544b111b5SSteffen Persvold	depends on NUMA
50644b111b5SSteffen Persvold	depends on SMP
50744b111b5SSteffen Persvold	depends on X86_X2APIC
508f9726bfdSDaniel J Blueman	depends on PCI_MMCONFIG
50944b111b5SSteffen Persvold	---help---
51044b111b5SSteffen Persvold	  Adds support for Numascale NumaChip large-SMP systems. Needed to
51144b111b5SSteffen Persvold	  enable more than ~168 cores.
51244b111b5SSteffen Persvold	  If you don't have one of these, you should say N here.
51303b48632SNick Piggin
5146a48565eSIngo Molnarconfig X86_VSMP
515c5c606d9SRavikiran G Thirumalai	bool "ScaleMP vSMP"
5166276a074SBorislav Petkov	select HYPERVISOR_GUEST
5176a48565eSIngo Molnar	select PARAVIRT
5186a48565eSIngo Molnar	depends on X86_64 && PCI
519c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
520ead91d4bSShai Fultheim	depends on SMP
5218f9ca475SIngo Molnar	---help---
5226a48565eSIngo Molnar	  Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
5236a48565eSIngo Molnar	  supposed to run on these EM64T-based machines.  Only choose this option
5246a48565eSIngo Molnar	  if you have one of these machines.
5256a48565eSIngo Molnar
526c5c606d9SRavikiran G Thirumalaiconfig X86_UV
527c5c606d9SRavikiran G Thirumalai	bool "SGI Ultraviolet"
528c5c606d9SRavikiran G Thirumalai	depends on X86_64
529c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
53054c28d29SJack Steiner	depends on NUMA
5311ecb4ae5SAndrew Morton	depends on EFI
5329d6c26e7SSuresh Siddha	depends on X86_X2APIC
5331222e564SIngo Molnar	depends on PCI
534c5c606d9SRavikiran G Thirumalai	---help---
535c5c606d9SRavikiran G Thirumalai	  This option is needed in order to support SGI Ultraviolet systems.
536c5c606d9SRavikiran G Thirumalai	  If you don't have one of these, you should say N here.
537c5c606d9SRavikiran G Thirumalai
538c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms
539c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions
540506f1d07SSam Ravnborg
541ddd70cf9SJun Nakajimaconfig X86_GOLDFISH
542ddd70cf9SJun Nakajima       bool "Goldfish (Virtual Platform)"
543cb7b8023SBen Hutchings       depends on X86_EXTENDED_PLATFORM
544ddd70cf9SJun Nakajima       ---help---
545ddd70cf9SJun Nakajima	 Enable support for the Goldfish virtual platform used primarily
546ddd70cf9SJun Nakajima	 for Android development. Unless you are building for the Android
547ddd70cf9SJun Nakajima	 Goldfish emulator say N here.
548ddd70cf9SJun Nakajima
549c751e17bSThomas Gleixnerconfig X86_INTEL_CE
550c751e17bSThomas Gleixner	bool "CE4100 TV platform"
551c751e17bSThomas Gleixner	depends on PCI
552c751e17bSThomas Gleixner	depends on PCI_GODIRECT
5536084a6e2SJiang Liu	depends on X86_IO_APIC
554c751e17bSThomas Gleixner	depends on X86_32
555c751e17bSThomas Gleixner	depends on X86_EXTENDED_PLATFORM
55637bc9f50SDirk Brandewie	select X86_REBOOTFIXUPS
557da6b737bSSebastian Andrzej Siewior	select OF
558da6b737bSSebastian Andrzej Siewior	select OF_EARLY_FLATTREE
559c751e17bSThomas Gleixner	---help---
560c751e17bSThomas Gleixner	  Select for the Intel CE media processor (CE4100) SOC.
561c751e17bSThomas Gleixner	  This option compiles in support for the CE4100 SOC for settop
562c751e17bSThomas Gleixner	  boxes and media devices.
563c751e17bSThomas Gleixner
5644cb9b00fSDavid Cohenconfig X86_INTEL_MID
56543605ef1SAlan Cox	bool "Intel MID platform support"
56643605ef1SAlan Cox	depends on X86_EXTENDED_PLATFORM
567edc6bc78SDavid Cohen	depends on X86_PLATFORM_DEVICES
5681ea7c673SAlan Cox	depends on PCI
5693fda5bb4SAndy Shevchenko	depends on X86_64 || (PCI_GOANY && X86_32)
5701ea7c673SAlan Cox	depends on X86_IO_APIC
5717c9c3a1eSAlan Cox	select SFI
5724cb9b00fSDavid Cohen	select I2C
5737c9c3a1eSAlan Cox	select DW_APB_TIMER
5741ea7c673SAlan Cox	select APB_TIMER
5751ea7c673SAlan Cox	select INTEL_SCU_IPC
57615a713dfSMika Westerberg	select MFD_INTEL_MSIC
5771ea7c673SAlan Cox	---help---
5784cb9b00fSDavid Cohen	  Select to build a kernel capable of supporting Intel MID (Mobile
5794cb9b00fSDavid Cohen	  Internet Device) platform systems which do not have the PCI legacy
5804cb9b00fSDavid Cohen	  interfaces. If you are building for a PC class system say N here.
5811ea7c673SAlan Cox
5824cb9b00fSDavid Cohen	  Intel MID platforms are based on an Intel processor and chipset which
5834cb9b00fSDavid Cohen	  consume less power than most of the x86 derivatives.
58443605ef1SAlan Cox
5858bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK
5868bbc2a13SBryan O'Donoghue	bool "Intel Quark platform support"
5878bbc2a13SBryan O'Donoghue	depends on X86_32
5888bbc2a13SBryan O'Donoghue	depends on X86_EXTENDED_PLATFORM
5898bbc2a13SBryan O'Donoghue	depends on X86_PLATFORM_DEVICES
5908bbc2a13SBryan O'Donoghue	depends on X86_TSC
5918bbc2a13SBryan O'Donoghue	depends on PCI
5928bbc2a13SBryan O'Donoghue	depends on PCI_GOANY
5938bbc2a13SBryan O'Donoghue	depends on X86_IO_APIC
5948bbc2a13SBryan O'Donoghue	select IOSF_MBI
5958bbc2a13SBryan O'Donoghue	select INTEL_IMR
5969ab6eb51SAndy Shevchenko	select COMMON_CLK
5978bbc2a13SBryan O'Donoghue	---help---
5988bbc2a13SBryan O'Donoghue	  Select to include support for Quark X1000 SoC.
5998bbc2a13SBryan O'Donoghue	  Say Y here if you have a Quark based system such as the Arduino
6008bbc2a13SBryan O'Donoghue	  compatible Intel Galileo.
6018bbc2a13SBryan O'Donoghue
6023d48aab1SMika Westerbergconfig X86_INTEL_LPSS
6033d48aab1SMika Westerberg	bool "Intel Low Power Subsystem Support"
604eebb3e8dSAndy Shevchenko	depends on X86 && ACPI
6053d48aab1SMika Westerberg	select COMMON_CLK
6060f531431SMathias Nyman	select PINCTRL
607eebb3e8dSAndy Shevchenko	select IOSF_MBI
6083d48aab1SMika Westerberg	---help---
6093d48aab1SMika Westerberg	  Select to build support for Intel Low Power Subsystem such as
6103d48aab1SMika Westerberg	  found on Intel Lynxpoint PCH. Selecting this option enables
6110f531431SMathias Nyman	  things like clock tree (common clock framework) and pincontrol
6120f531431SMathias Nyman	  which are needed by the LPSS peripheral drivers.
6133d48aab1SMika Westerberg
61492082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE
61592082a88SKen Xue	bool "AMD ACPI2Platform devices support"
61692082a88SKen Xue	depends on ACPI
61792082a88SKen Xue	select COMMON_CLK
61892082a88SKen Xue	select PINCTRL
61992082a88SKen Xue	---help---
62092082a88SKen Xue	  Select to interpret AMD specific ACPI device to platform device
62192082a88SKen Xue	  such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
62292082a88SKen Xue	  I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
62392082a88SKen Xue	  implemented under PINCTRL subsystem.
62492082a88SKen Xue
625ced3ce76SDavid E. Boxconfig IOSF_MBI
626ced3ce76SDavid E. Box	tristate "Intel SoC IOSF Sideband support for SoC platforms"
627ced3ce76SDavid E. Box	depends on PCI
628ced3ce76SDavid E. Box	---help---
629ced3ce76SDavid E. Box	  This option enables sideband register access support for Intel SoC
630ced3ce76SDavid E. Box	  platforms. On these platforms the IOSF sideband is used in lieu of
631ced3ce76SDavid E. Box	  MSR's for some register accesses, mostly but not limited to thermal
632ced3ce76SDavid E. Box	  and power. Drivers may query the availability of this device to
633ced3ce76SDavid E. Box	  determine if they need the sideband in order to work on these
634ced3ce76SDavid E. Box	  platforms. The sideband is available on the following SoC products.
635ced3ce76SDavid E. Box	  This list is not meant to be exclusive.
636ced3ce76SDavid E. Box	   - BayTrail
637ced3ce76SDavid E. Box	   - Braswell
638ced3ce76SDavid E. Box	   - Quark
639ced3ce76SDavid E. Box
640ced3ce76SDavid E. Box	  You should say Y if you are running a kernel on one of these SoC's.
641ced3ce76SDavid E. Box
642ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG
643ed2226bdSDavid E. Box	bool "Enable IOSF sideband access through debugfs"
644ed2226bdSDavid E. Box	depends on IOSF_MBI && DEBUG_FS
645ed2226bdSDavid E. Box	---help---
646ed2226bdSDavid E. Box	  Select this option to expose the IOSF sideband access registers (MCR,
647ed2226bdSDavid E. Box	  MDR, MCRX) through debugfs to write and read register information from
648ed2226bdSDavid E. Box	  different units on the SoC. This is most useful for obtaining device
649ed2226bdSDavid E. Box	  state information for debug and analysis. As this is a general access
650ed2226bdSDavid E. Box	  mechanism, users of this option would have specific knowledge of the
651ed2226bdSDavid E. Box	  device they want to access.
652ed2226bdSDavid E. Box
653ed2226bdSDavid E. Box	  If you don't require the option or are in doubt, say N.
654ed2226bdSDavid E. Box
655c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X
656c5c606d9SRavikiran G Thirumalai	bool "RDC R-321x SoC"
657506f1d07SSam Ravnborg	depends on X86_32
658c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
659c5c606d9SRavikiran G Thirumalai	select M486
660c5c606d9SRavikiran G Thirumalai	select X86_REBOOTFIXUPS
661c5c606d9SRavikiran G Thirumalai	---help---
662c5c606d9SRavikiran G Thirumalai	  This option is needed for RDC R-321x system-on-chip, also known
663c5c606d9SRavikiran G Thirumalai	  as R-8610-(G).
664c5c606d9SRavikiran G Thirumalai	  If you don't have one of these chips, you should say N here.
665c5c606d9SRavikiran G Thirumalai
666e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD
6679c398017SIngo Molnar	bool "Support non-standard 32-bit SMP architectures"
6689c398017SIngo Molnar	depends on X86_32 && SMP
669c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
6708f9ca475SIngo Molnar	---help---
671b5660ba7SH. Peter Anvin	  This option compiles in the bigsmp and STA2X11 default
672b5660ba7SH. Peter Anvin	  subarchitectures.  It is intended for a generic binary
673b5660ba7SH. Peter Anvin	  kernel. If you select them all, kernel will probe it one by
674b5660ba7SH. Peter Anvin	  one and will fallback to default.
675d49c4288SYinghai Lu
676c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms
677d49c4288SYinghai Lu
678d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE
6796fc108a0SJan Beulich	def_bool y
680d949f36fSLinus Torvalds	# MCE code calls memory_failure():
681d949f36fSLinus Torvalds	depends on X86_MCE
682d949f36fSLinus Torvalds	# On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
683d949f36fSLinus Torvalds	# On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
684d949f36fSLinus Torvalds	depends on X86_64 || !SPARSEMEM
685d949f36fSLinus Torvalds	select ARCH_SUPPORTS_MEMORY_FAILURE
686d949f36fSLinus Torvalds
68783125a3aSAlessandro Rubiniconfig STA2X11
68883125a3aSAlessandro Rubini	bool "STA2X11 Companion Chip Support"
68983125a3aSAlessandro Rubini	depends on X86_32_NON_STANDARD && PCI
69083125a3aSAlessandro Rubini	select X86_DEV_DMA_OPS
69183125a3aSAlessandro Rubini	select X86_DMA_REMAP
69283125a3aSAlessandro Rubini	select SWIOTLB
69383125a3aSAlessandro Rubini	select MFD_STA2X11
6940145071bSLinus Walleij	select GPIOLIB
69583125a3aSAlessandro Rubini	default n
69683125a3aSAlessandro Rubini	---help---
69783125a3aSAlessandro Rubini	  This adds support for boards based on the STA2X11 IO-Hub,
69883125a3aSAlessandro Rubini	  a.k.a. "ConneXt". The chip is used in place of the standard
69983125a3aSAlessandro Rubini	  PC chipset, so all "standard" peripherals are missing. If this
70083125a3aSAlessandro Rubini	  option is selected the kernel will still be able to boot on
70183125a3aSAlessandro Rubini	  standard PC machines.
70283125a3aSAlessandro Rubini
70382148d1dSShérabconfig X86_32_IRIS
70482148d1dSShérab	tristate "Eurobraille/Iris poweroff module"
70582148d1dSShérab	depends on X86_32
70682148d1dSShérab	---help---
70782148d1dSShérab	  The Iris machines from EuroBraille do not have APM or ACPI support
70882148d1dSShérab	  to shut themselves down properly.  A special I/O sequence is
70982148d1dSShérab	  needed to do so, which is what this module does at
71082148d1dSShérab	  kernel shutdown.
71182148d1dSShérab
71282148d1dSShérab	  This is only for Iris machines from EuroBraille.
71382148d1dSShérab
71482148d1dSShérab	  If unused, say N.
71582148d1dSShérab
716ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER
7173c2362e6SHarvey Harrison	def_bool y
7183c2362e6SHarvey Harrison	prompt "Single-depth WCHAN output"
719a87d0914SKen Chen	depends on X86
7208f9ca475SIngo Molnar	---help---
721506f1d07SSam Ravnborg	  Calculate simpler /proc/<PID>/wchan values. If this option
722506f1d07SSam Ravnborg	  is disabled then wchan values will recurse back to the
723506f1d07SSam Ravnborg	  caller function. This provides more accurate wchan values,
724506f1d07SSam Ravnborg	  at the expense of slightly more scheduling overhead.
725506f1d07SSam Ravnborg
726506f1d07SSam Ravnborg	  If in doubt, say "Y".
727506f1d07SSam Ravnborg
7286276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST
7296276a074SBorislav Petkov	bool "Linux guest support"
7308f9ca475SIngo Molnar	---help---
7316276a074SBorislav Petkov	  Say Y here to enable options for running Linux under various hyper-
7326276a074SBorislav Petkov	  visors. This option enables basic hypervisor detection and platform
7336276a074SBorislav Petkov	  setup.
734506f1d07SSam Ravnborg
7356276a074SBorislav Petkov	  If you say N, all options in this submenu will be skipped and
7366276a074SBorislav Petkov	  disabled, and Linux guest support won't be built in.
737506f1d07SSam Ravnborg
7386276a074SBorislav Petkovif HYPERVISOR_GUEST
739506f1d07SSam Ravnborg
740e61bd94aSEduardo Pereira Habkostconfig PARAVIRT
741e61bd94aSEduardo Pereira Habkost	bool "Enable paravirtualization code"
7428f9ca475SIngo Molnar	---help---
743e61bd94aSEduardo Pereira Habkost	  This changes the kernel so it can modify itself when it is run
744e61bd94aSEduardo Pereira Habkost	  under a hypervisor, potentially improving performance significantly
745e61bd94aSEduardo Pereira Habkost	  over full virtualization.  However, when run without a hypervisor
746e61bd94aSEduardo Pereira Habkost	  the kernel is theoretically slower and slightly larger.
747e61bd94aSEduardo Pereira Habkost
7486276a074SBorislav Petkovconfig PARAVIRT_DEBUG
7496276a074SBorislav Petkov	bool "paravirt-ops debugging"
7506276a074SBorislav Petkov	depends on PARAVIRT && DEBUG_KERNEL
7516276a074SBorislav Petkov	---help---
7526276a074SBorislav Petkov	  Enable to debug paravirt_ops internals.  Specifically, BUG if
7536276a074SBorislav Petkov	  a paravirt_op is missing when it is called.
7546276a074SBorislav Petkov
755b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS
756b4ecc126SJeremy Fitzhardinge	bool "Paravirtualization layer for spinlocks"
7576ea30386SKees Cook	depends on PARAVIRT && SMP
758b4ecc126SJeremy Fitzhardinge	---help---
759b4ecc126SJeremy Fitzhardinge	  Paravirtualized spinlocks allow a pvops backend to replace the
760b4ecc126SJeremy Fitzhardinge	  spinlock implementation with something virtualization-friendly
761b4ecc126SJeremy Fitzhardinge	  (for example, block the virtual CPU rather than spinning).
762b4ecc126SJeremy Fitzhardinge
7634c4e4f61SRaghavendra K T	  It has a minimal impact on native kernels and gives a nice performance
7644c4e4f61SRaghavendra K T	  benefit on paravirtualized KVM / Xen kernels.
765b4ecc126SJeremy Fitzhardinge
7664c4e4f61SRaghavendra K T	  If you are unsure how to answer this question, answer Y.
767b4ecc126SJeremy Fitzhardinge
76845e898b7SWaiman Longconfig QUEUED_LOCK_STAT
76945e898b7SWaiman Long	bool "Paravirt queued spinlock statistics"
770cfd8983fSPeter Zijlstra	depends on PARAVIRT_SPINLOCKS && DEBUG_FS
77145e898b7SWaiman Long	---help---
77245e898b7SWaiman Long	  Enable the collection of statistical data on the slowpath
77345e898b7SWaiman Long	  behavior of paravirtualized queued spinlocks and report
77445e898b7SWaiman Long	  them on debugfs.
77545e898b7SWaiman Long
7766276a074SBorislav Petkovsource "arch/x86/xen/Kconfig"
7776276a074SBorislav Petkov
7786276a074SBorislav Petkovconfig KVM_GUEST
7796276a074SBorislav Petkov	bool "KVM Guest support (including kvmclock)"
7806276a074SBorislav Petkov	depends on PARAVIRT
7816276a074SBorislav Petkov	select PARAVIRT_CLOCK
7826276a074SBorislav Petkov	default y
7836276a074SBorislav Petkov	---help---
7846276a074SBorislav Petkov	  This option enables various optimizations for running under the KVM
7856276a074SBorislav Petkov	  hypervisor. It includes a paravirtualized clock, so that instead
7866276a074SBorislav Petkov	  of relying on a PIT (or probably other) emulation by the
7876276a074SBorislav Petkov	  underlying device model, the host provides the guest with
7886276a074SBorislav Petkov	  timing infrastructure such as time of day, and system time
7896276a074SBorislav Petkov
7901e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS
7911e20eb85SSrivatsa Vaddagiri	bool "Enable debug information for KVM Guests in debugfs"
7921e20eb85SSrivatsa Vaddagiri	depends on KVM_GUEST && DEBUG_FS
7931e20eb85SSrivatsa Vaddagiri	default n
7941e20eb85SSrivatsa Vaddagiri	---help---
7951e20eb85SSrivatsa Vaddagiri	  This option enables collection of various statistics for KVM guest.
7961e20eb85SSrivatsa Vaddagiri	  Statistics are displayed in debugfs filesystem. Enabling this option
7971e20eb85SSrivatsa Vaddagiri	  may incur significant overhead.
7981e20eb85SSrivatsa Vaddagiri
7996276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING
8006276a074SBorislav Petkov	bool "Paravirtual steal time accounting"
8016276a074SBorislav Petkov	depends on PARAVIRT
8026276a074SBorislav Petkov	default n
8036276a074SBorislav Petkov	---help---
8046276a074SBorislav Petkov	  Select this option to enable fine granularity task steal time
8056276a074SBorislav Petkov	  accounting. Time spent executing other tasks in parallel with
8066276a074SBorislav Petkov	  the current vCPU is discounted from the vCPU power. To account for
8076276a074SBorislav Petkov	  that, there can be a small performance impact.
8086276a074SBorislav Petkov
8096276a074SBorislav Petkov	  If in doubt, say N here.
8106276a074SBorislav Petkov
8117af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK
8127af192c9SGerd Hoffmann	bool
8137af192c9SGerd Hoffmann
8144a362601SJan Kiszkaconfig JAILHOUSE_GUEST
8154a362601SJan Kiszka	bool "Jailhouse non-root cell support"
816abde587bSArnd Bergmann	depends on X86_64 && PCI
81787e65d05SJan Kiszka	select X86_PM_TIMER
8184a362601SJan Kiszka	---help---
8194a362601SJan Kiszka	  This option allows to run Linux as guest in a Jailhouse non-root
8204a362601SJan Kiszka	  cell. You can leave this option disabled if you only want to start
8214a362601SJan Kiszka	  Jailhouse and run Linux afterwards in the root cell.
8224a362601SJan Kiszka
8236276a074SBorislav Petkovendif #HYPERVISOR_GUEST
82497349135SJeremy Fitzhardinge
82508677214SYinghai Luconfig NO_BOOTMEM
826774ea0bcSYinghai Lu	def_bool y
82708677214SYinghai Lu
828506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu"
829506f1d07SSam Ravnborg
830506f1d07SSam Ravnborgconfig HPET_TIMER
8313c2362e6SHarvey Harrison	def_bool X86_64
832506f1d07SSam Ravnborg	prompt "HPET Timer Support" if X86_32
8338f9ca475SIngo Molnar	---help---
834506f1d07SSam Ravnborg	  Use the IA-PC HPET (High Precision Event Timer) to manage
835506f1d07SSam Ravnborg	  time in preference to the PIT and RTC, if a HPET is
836506f1d07SSam Ravnborg	  present.
837506f1d07SSam Ravnborg	  HPET is the next generation timer replacing legacy 8254s.
838506f1d07SSam Ravnborg	  The HPET provides a stable time base on SMP
839506f1d07SSam Ravnborg	  systems, unlike the TSC, but it is more expensive to access,
8404e7f9df2SMichael S. Tsirkin	  as it is off-chip.  The interface used is documented
8414e7f9df2SMichael S. Tsirkin	  in the HPET spec, revision 1.
842506f1d07SSam Ravnborg
843506f1d07SSam Ravnborg	  You can safely choose Y here.  However, HPET will only be
844506f1d07SSam Ravnborg	  activated if the platform and the BIOS support this feature.
845506f1d07SSam Ravnborg	  Otherwise the 8254 will be used for timing services.
846506f1d07SSam Ravnborg
847506f1d07SSam Ravnborg	  Choose N to continue using the legacy 8254 timer.
848506f1d07SSam Ravnborg
849506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC
8503c2362e6SHarvey Harrison	def_bool y
8519d8af78bSBernhard Walle	depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
852506f1d07SSam Ravnborg
853bb24c471SJacob Panconfig APB_TIMER
854933b9463SAlan Cox       def_bool y if X86_INTEL_MID
855933b9463SAlan Cox       prompt "Intel MID APB Timer Support" if X86_INTEL_MID
85606c3df49SJamie Iles       select DW_APB_TIMER
857a0c3832aSAlan Cox       depends on X86_INTEL_MID && SFI
858bb24c471SJacob Pan       help
859bb24c471SJacob Pan         APB timer is the replacement for 8254, HPET on X86 MID platforms.
860bb24c471SJacob Pan         The APBT provides a stable time base on SMP
861bb24c471SJacob Pan         systems, unlike the TSC, but it is more expensive to access,
862bb24c471SJacob Pan         as it is off-chip. APB timers are always running regardless of CPU
863bb24c471SJacob Pan         C states, they are used as per CPU clockevent device when possible.
864bb24c471SJacob Pan
8656a108a14SDavid Rientjes# Mark as expert because too many people got it wrong.
866506f1d07SSam Ravnborg# The code disables itself when not needed.
8677ae9392cSThomas Petazzoniconfig DMI
8687ae9392cSThomas Petazzoni	default y
869cf074402SArd Biesheuvel	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
8706a108a14SDavid Rientjes	bool "Enable DMI scanning" if EXPERT
8718f9ca475SIngo Molnar	---help---
8727ae9392cSThomas Petazzoni	  Enabled scanning of DMI to identify machine quirks. Say Y
8737ae9392cSThomas Petazzoni	  here unless you have verified that your setup is not
8747ae9392cSThomas Petazzoni	  affected by entries in the DMI blacklist. Required by PNP
8757ae9392cSThomas Petazzoni	  BIOS code.
8767ae9392cSThomas Petazzoni
877506f1d07SSam Ravnborgconfig GART_IOMMU
87838901f1cSAndi Kleen	bool "Old AMD GART IOMMU support"
879506f1d07SSam Ravnborg	select SWIOTLB
88023ac4ae8SAndreas Herrmann	depends on X86_64 && PCI && AMD_NB
8818f9ca475SIngo Molnar	---help---
882ced3c42cSIngo Molnar	  Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
883ced3c42cSIngo Molnar	  GART based hardware IOMMUs.
884ced3c42cSIngo Molnar
885ced3c42cSIngo Molnar	  The GART supports full DMA access for devices with 32-bit access
886ced3c42cSIngo Molnar	  limitations, on systems with more than 3 GB. This is usually needed
887ced3c42cSIngo Molnar	  for USB, sound, many IDE/SATA chipsets and some other devices.
888ced3c42cSIngo Molnar
889ced3c42cSIngo Molnar	  Newer systems typically have a modern AMD IOMMU, supported via
890ced3c42cSIngo Molnar	  the CONFIG_AMD_IOMMU=y config option.
891ced3c42cSIngo Molnar
892ced3c42cSIngo Molnar	  In normal configurations this driver is only active when needed:
893ced3c42cSIngo Molnar	  there's more than 3 GB of memory and the system contains a
894ced3c42cSIngo Molnar	  32-bit limited device.
895ced3c42cSIngo Molnar
896ced3c42cSIngo Molnar	  If unsure, say Y.
897506f1d07SSam Ravnborg
898506f1d07SSam Ravnborgconfig CALGARY_IOMMU
899506f1d07SSam Ravnborg	bool "IBM Calgary IOMMU support"
900506f1d07SSam Ravnborg	select SWIOTLB
9016ea30386SKees Cook	depends on X86_64 && PCI
9028f9ca475SIngo Molnar	---help---
903506f1d07SSam Ravnborg	  Support for hardware IOMMUs in IBM's xSeries x366 and x460
904506f1d07SSam Ravnborg	  systems. Needed to run systems with more than 3GB of memory
905506f1d07SSam Ravnborg	  properly with 32-bit PCI devices that do not support DAC
906506f1d07SSam Ravnborg	  (Double Address Cycle). Calgary also supports bus level
907506f1d07SSam Ravnborg	  isolation, where all DMAs pass through the IOMMU.  This
908506f1d07SSam Ravnborg	  prevents them from going anywhere except their intended
909506f1d07SSam Ravnborg	  destination. This catches hard-to-find kernel bugs and
910506f1d07SSam Ravnborg	  mis-behaving drivers and devices that do not use the DMA-API
911506f1d07SSam Ravnborg	  properly to set up their DMA buffers.  The IOMMU can be
912506f1d07SSam Ravnborg	  turned off at boot time with the iommu=off parameter.
913506f1d07SSam Ravnborg	  Normally the kernel will make the right choice by itself.
914506f1d07SSam Ravnborg	  If unsure, say Y.
915506f1d07SSam Ravnborg
916506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT
9173c2362e6SHarvey Harrison	def_bool y
9183c2362e6SHarvey Harrison	prompt "Should Calgary be enabled by default?"
919506f1d07SSam Ravnborg	depends on CALGARY_IOMMU
9208f9ca475SIngo Molnar	---help---
921506f1d07SSam Ravnborg	  Should Calgary be enabled by default? if you choose 'y', Calgary
922506f1d07SSam Ravnborg	  will be used (if it exists). If you choose 'n', Calgary will not be
923506f1d07SSam Ravnborg	  used even if it exists. If you choose 'n' and would like to use
924506f1d07SSam Ravnborg	  Calgary anyway, pass 'iommu=calgary' on the kernel command line.
925506f1d07SSam Ravnborg	  If unsure, say Y.
926506f1d07SSam Ravnborg
927506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround
928506f1d07SSam Ravnborgconfig SWIOTLB
929a1afd01cSJoerg Roedel	def_bool y if X86_64
9308f9ca475SIngo Molnar	---help---
931506f1d07SSam Ravnborg	  Support for software bounce buffers used on x86-64 systems
9324454d327SJoe Millenbach	  which don't have a hardware IOMMU. Using this PCI devices
9334454d327SJoe Millenbach	  which can only access 32-bits of memory can be used on systems
9344454d327SJoe Millenbach	  with more than 3 GB of memory.
9354454d327SJoe Millenbach	  If unsure, say Y.
936506f1d07SSam Ravnborg
937a8522509SFUJITA Tomonoriconfig IOMMU_HELPER
9383120e25eSJan Beulich	def_bool y
9393120e25eSJan Beulich	depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
940d25e26b6SLinus Torvalds
9411184dc2fSMike Travisconfig MAXSMP
942ddb0c5a6SSamuel Thibault	bool "Enable Maximum number of SMP Processors and NUMA Nodes"
9436ea30386SKees Cook	depends on X86_64 && SMP && DEBUG_KERNEL
94436f5101aSMike Travis	select CPUMASK_OFFSTACK
9458f9ca475SIngo Molnar	---help---
946ddb0c5a6SSamuel Thibault	  Enable maximum number of CPUS and NUMA Nodes for this architecture.
9471184dc2fSMike Travis	  If unsure, say N.
948506f1d07SSam Ravnborg
949506f1d07SSam Ravnborgconfig NR_CPUS
95036f5101aSMike Travis	int "Maximum number of CPUs" if SMP && !MAXSMP
9512a3313f4SMichael K. Johnson	range 2 8 if SMP && X86_32 && !X86_BIGSMP
9527bbcbd3dSThomas Gleixner	range 2 64 if SMP && X86_32 && X86_BIGSMP
9537bbcbd3dSThomas Gleixner	range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK && X86_64
954b53b5edaSJosh Boyer	range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
95578637a97SMike Travis	default "1" if !SMP
956b53b5edaSJosh Boyer	default "8192" if MAXSMP
957b5660ba7SH. Peter Anvin	default "32" if SMP && X86_BIGSMP
958c5c19941SKirill A. Shutemov	default "8" if SMP && X86_32
959c5c19941SKirill A. Shutemov	default "64" if SMP
9608f9ca475SIngo Molnar	---help---
961506f1d07SSam Ravnborg	  This allows you to specify the maximum number of CPUs which this
962bb61ccc7SJosh Boyer	  kernel will support.  If CPUMASK_OFFSTACK is enabled, the maximum
963cad14bb9SKirill A. Shutemov	  supported value is 8192, otherwise the maximum value is 512.  The
964506f1d07SSam Ravnborg	  minimum value which makes sense is 2.
965506f1d07SSam Ravnborg
966506f1d07SSam Ravnborg	  This is purely to save memory - each supported CPU adds
967506f1d07SSam Ravnborg	  approximately eight kilobytes to the kernel image.
968506f1d07SSam Ravnborg
969506f1d07SSam Ravnborgconfig SCHED_SMT
970506f1d07SSam Ravnborg	bool "SMT (Hyperthreading) scheduler support"
971c8e56d20SBorislav Petkov	depends on SMP
9728f9ca475SIngo Molnar	---help---
973506f1d07SSam Ravnborg	  SMT scheduler support improves the CPU scheduler's decision making
974506f1d07SSam Ravnborg	  when dealing with Intel Pentium 4 chips with HyperThreading at a
975506f1d07SSam Ravnborg	  cost of slightly increased overhead in some places. If unsure say
976506f1d07SSam Ravnborg	  N here.
977506f1d07SSam Ravnborg
978506f1d07SSam Ravnborgconfig SCHED_MC
9793c2362e6SHarvey Harrison	def_bool y
9803c2362e6SHarvey Harrison	prompt "Multi-core scheduler support"
981c8e56d20SBorislav Petkov	depends on SMP
9828f9ca475SIngo Molnar	---help---
983506f1d07SSam Ravnborg	  Multi-core scheduler support improves the CPU scheduler's decision
984506f1d07SSam Ravnborg	  making when dealing with multi-core CPU chips at a cost of slightly
985506f1d07SSam Ravnborg	  increased overhead in some places. If unsure say N here.
986506f1d07SSam Ravnborg
987de966cf4STim Chenconfig SCHED_MC_PRIO
988de966cf4STim Chen	bool "CPU core priorities scheduler support"
9890a21fc12SIngo Molnar	depends on SCHED_MC && CPU_SUP_INTEL
9900a21fc12SIngo Molnar	select X86_INTEL_PSTATE
9910a21fc12SIngo Molnar	select CPU_FREQ
992de966cf4STim Chen	default y
9935e76b2abSTim Chen	---help---
994de966cf4STim Chen	  Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
995de966cf4STim Chen	  core ordering determined at manufacturing time, which allows
996de966cf4STim Chen	  certain cores to reach higher turbo frequencies (when running
997de966cf4STim Chen	  single threaded workloads) than others.
998de966cf4STim Chen
999de966cf4STim Chen	  Enabling this kernel feature teaches the scheduler about
1000de966cf4STim Chen	  the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1001de966cf4STim Chen	  scheduler's CPU selection logic accordingly, so that higher
1002de966cf4STim Chen	  overall system performance can be achieved.
1003de966cf4STim Chen
1004de966cf4STim Chen	  This feature will have no effect on CPUs without this feature.
1005de966cf4STim Chen
1006de966cf4STim Chen	  If unsure say Y here.
10075e76b2abSTim Chen
1008506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt"
1009506f1d07SSam Ravnborg
101030b8b006SThomas Gleixnerconfig UP_LATE_INIT
101130b8b006SThomas Gleixner       def_bool y
1012ba360f88SThomas Gleixner       depends on !SMP && X86_LOCAL_APIC
101330b8b006SThomas Gleixner
1014506f1d07SSam Ravnborgconfig X86_UP_APIC
101550849eefSJan Beulich	bool "Local APIC support on uniprocessors" if !PCI_MSI
101650849eefSJan Beulich	default PCI_MSI
101738a1dfdaSBryan O'Donoghue	depends on X86_32 && !SMP && !X86_32_NON_STANDARD
10188f9ca475SIngo Molnar	---help---
1019506f1d07SSam Ravnborg	  A local APIC (Advanced Programmable Interrupt Controller) is an
1020506f1d07SSam Ravnborg	  integrated interrupt controller in the CPU. If you have a single-CPU
1021506f1d07SSam Ravnborg	  system which has a processor with a local APIC, you can say Y here to
1022506f1d07SSam Ravnborg	  enable and use it. If you say Y here even though your machine doesn't
1023506f1d07SSam Ravnborg	  have a local APIC, then the kernel will still run with no slowdown at
1024506f1d07SSam Ravnborg	  all. The local APIC supports CPU-generated self-interrupts (timer,
1025506f1d07SSam Ravnborg	  performance counters), and the NMI watchdog which detects hard
1026506f1d07SSam Ravnborg	  lockups.
1027506f1d07SSam Ravnborg
1028506f1d07SSam Ravnborgconfig X86_UP_IOAPIC
1029506f1d07SSam Ravnborg	bool "IO-APIC support on uniprocessors"
1030506f1d07SSam Ravnborg	depends on X86_UP_APIC
10318f9ca475SIngo Molnar	---help---
1032506f1d07SSam Ravnborg	  An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1033506f1d07SSam Ravnborg	  SMP-capable replacement for PC-style interrupt controllers. Most
1034506f1d07SSam Ravnborg	  SMP systems and many recent uniprocessor systems have one.
1035506f1d07SSam Ravnborg
1036506f1d07SSam Ravnborg	  If you have a single-CPU system with an IO-APIC, you can say Y here
1037506f1d07SSam Ravnborg	  to use it. If you say Y here even though your machine doesn't have
1038506f1d07SSam Ravnborg	  an IO-APIC, then the kernel will still run with no slowdown at all.
1039506f1d07SSam Ravnborg
1040506f1d07SSam Ravnborgconfig X86_LOCAL_APIC
10413c2362e6SHarvey Harrison	def_bool y
10420dbc6078SThomas Petazzoni	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
1043b5dc8e6cSJiang Liu	select IRQ_DOMAIN_HIERARCHY
104452f518a3SJiang Liu	select PCI_MSI_IRQ_DOMAIN if PCI_MSI
1045506f1d07SSam Ravnborg
1046506f1d07SSam Ravnborgconfig X86_IO_APIC
1047b1da1e71SJan Beulich	def_bool y
1048b1da1e71SJan Beulich	depends on X86_LOCAL_APIC || X86_UP_IOAPIC
1049506f1d07SSam Ravnborg
105041b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS
105141b9eb26SStefan Assmann	bool "Reroute for broken boot IRQs"
105241b9eb26SStefan Assmann	depends on X86_IO_APIC
10538f9ca475SIngo Molnar	---help---
105441b9eb26SStefan Assmann	  This option enables a workaround that fixes a source of
105541b9eb26SStefan Assmann	  spurious interrupts. This is recommended when threaded
105641b9eb26SStefan Assmann	  interrupt handling is used on systems where the generation of
105741b9eb26SStefan Assmann	  superfluous "boot interrupts" cannot be disabled.
105841b9eb26SStefan Assmann
105941b9eb26SStefan Assmann	  Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
106041b9eb26SStefan Assmann	  entry in the chipset's IO-APIC is masked (as, e.g. the RT
106141b9eb26SStefan Assmann	  kernel does during interrupt handling). On chipsets where this
106241b9eb26SStefan Assmann	  boot IRQ generation cannot be disabled, this workaround keeps
106341b9eb26SStefan Assmann	  the original IRQ line masked so that only the equivalent "boot
106441b9eb26SStefan Assmann	  IRQ" is delivered to the CPUs. The workaround also tells the
106541b9eb26SStefan Assmann	  kernel to set up the IRQ handler on the boot IRQ line. In this
106641b9eb26SStefan Assmann	  way only one interrupt is delivered to the kernel. Otherwise
106741b9eb26SStefan Assmann	  the spurious second interrupt may cause the kernel to bring
106841b9eb26SStefan Assmann	  down (vital) interrupt lines.
106941b9eb26SStefan Assmann
107041b9eb26SStefan Assmann	  Only affects "broken" chipsets. Interrupt sharing may be
107141b9eb26SStefan Assmann	  increased on these systems.
107241b9eb26SStefan Assmann
1073506f1d07SSam Ravnborgconfig X86_MCE
1074bab9bc65SAndi Kleen	bool "Machine Check / overheating reporting"
1075648ed940SChen, Gong	select GENERIC_ALLOCATOR
1076e57dbaf7SBorislav Petkov	default y
1077506f1d07SSam Ravnborg	---help---
1078bab9bc65SAndi Kleen	  Machine Check support allows the processor to notify the
1079bab9bc65SAndi Kleen	  kernel if it detects a problem (e.g. overheating, data corruption).
1080506f1d07SSam Ravnborg	  The action the kernel takes depends on the severity of the problem,
1081bab9bc65SAndi Kleen	  ranging from warning messages to halting the machine.
10824efc0670SAndi Kleen
10835de97c9fSTony Luckconfig X86_MCELOG_LEGACY
10845de97c9fSTony Luck	bool "Support for deprecated /dev/mcelog character device"
10855de97c9fSTony Luck	depends on X86_MCE
10865de97c9fSTony Luck	---help---
10875de97c9fSTony Luck	  Enable support for /dev/mcelog which is needed by the old mcelog
10885de97c9fSTony Luck	  userspace logging daemon. Consider switching to the new generation
10895de97c9fSTony Luck	  rasdaemon solution.
10905de97c9fSTony Luck
1091506f1d07SSam Ravnborgconfig X86_MCE_INTEL
10923c2362e6SHarvey Harrison	def_bool y
10933c2362e6SHarvey Harrison	prompt "Intel MCE features"
1094c1ebf835SAndi Kleen	depends on X86_MCE && X86_LOCAL_APIC
10958f9ca475SIngo Molnar	---help---
1096506f1d07SSam Ravnborg	   Additional support for intel specific MCE features such as
1097506f1d07SSam Ravnborg	   the thermal monitor.
1098506f1d07SSam Ravnborg
1099506f1d07SSam Ravnborgconfig X86_MCE_AMD
11003c2362e6SHarvey Harrison	def_bool y
11013c2362e6SHarvey Harrison	prompt "AMD MCE features"
1102f5382de9SYazen Ghannam	depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
11038f9ca475SIngo Molnar	---help---
1104506f1d07SSam Ravnborg	   Additional support for AMD specific MCE features such as
1105506f1d07SSam Ravnborg	   the DRAM Error Threshold.
1106506f1d07SSam Ravnborg
11074efc0670SAndi Kleenconfig X86_ANCIENT_MCE
11086fc108a0SJan Beulich	bool "Support for old Pentium 5 / WinChip machine checks"
1109c31d9633SAndi Kleen	depends on X86_32 && X86_MCE
11104efc0670SAndi Kleen	---help---
11114efc0670SAndi Kleen	  Include support for machine check handling on old Pentium 5 or WinChip
11125065a706SMasanari Iida	  systems. These typically need to be enabled explicitly on the command
11134efc0670SAndi Kleen	  line.
11144efc0670SAndi Kleen
1115b2762686SAndi Kleenconfig X86_MCE_THRESHOLD
1116b2762686SAndi Kleen	depends on X86_MCE_AMD || X86_MCE_INTEL
11176fc108a0SJan Beulich	def_bool y
1118b2762686SAndi Kleen
1119ea149b36SAndi Kleenconfig X86_MCE_INJECT
1120bc8e80d5SBorislav Petkov	depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
1121ea149b36SAndi Kleen	tristate "Machine check injector support"
1122ea149b36SAndi Kleen	---help---
1123ea149b36SAndi Kleen	  Provide support for injecting machine checks for testing purposes.
1124ea149b36SAndi Kleen	  If you don't know what a machine check is and you don't do kernel
1125ea149b36SAndi Kleen	  QA it is safe to say n.
1126ea149b36SAndi Kleen
11274efc0670SAndi Kleenconfig X86_THERMAL_VECTOR
11284efc0670SAndi Kleen	def_bool y
11295bb38adcSAndi Kleen	depends on X86_MCE_INTEL
11304efc0670SAndi Kleen
113107dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig"
1132e633c65aSKan Liang
11335aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86
11341e642812SIngo Molnar	bool "Legacy VM86 support"
11355aef51c3SAndy Lutomirski	default n
1136506f1d07SSam Ravnborg	depends on X86_32
11378f9ca475SIngo Molnar	---help---
11385aef51c3SAndy Lutomirski	  This option allows user programs to put the CPU into V8086
11395aef51c3SAndy Lutomirski	  mode, which is an 80286-era approximation of 16-bit real mode.
11405aef51c3SAndy Lutomirski
11415aef51c3SAndy Lutomirski	  Some very old versions of X and/or vbetool require this option
11425aef51c3SAndy Lutomirski	  for user mode setting.  Similarly, DOSEMU will use it if
11435aef51c3SAndy Lutomirski	  available to accelerate real mode DOS programs.  However, any
11445aef51c3SAndy Lutomirski	  recent version of DOSEMU, X, or vbetool should be fully
11455aef51c3SAndy Lutomirski	  functional even without kernel VM86 support, as they will all
11461e642812SIngo Molnar	  fall back to software emulation. Nevertheless, if you are using
11471e642812SIngo Molnar	  a 16-bit DOS program where 16-bit performance matters, vm86
11481e642812SIngo Molnar	  mode might be faster than emulation and you might want to
11491e642812SIngo Molnar	  enable this option.
11505aef51c3SAndy Lutomirski
11511e642812SIngo Molnar	  Note that any app that works on a 64-bit kernel is unlikely to
11521e642812SIngo Molnar	  need this option, as 64-bit kernels don't, and can't, support
11531e642812SIngo Molnar	  V8086 mode. This option is also unrelated to 16-bit protected
11541e642812SIngo Molnar	  mode and is not needed to run most 16-bit programs under Wine.
11555aef51c3SAndy Lutomirski
11561e642812SIngo Molnar	  Enabling this option increases the complexity of the kernel
11571e642812SIngo Molnar	  and slows down exception handling a tiny bit.
11585aef51c3SAndy Lutomirski
11591e642812SIngo Molnar	  If unsure, say N here.
11605aef51c3SAndy Lutomirski
11615aef51c3SAndy Lutomirskiconfig VM86
11625aef51c3SAndy Lutomirski       bool
11635aef51c3SAndy Lutomirski       default X86_LEGACY_VM86
116434273f41SH. Peter Anvin
116534273f41SH. Peter Anvinconfig X86_16BIT
116634273f41SH. Peter Anvin	bool "Enable support for 16-bit segments" if EXPERT
116734273f41SH. Peter Anvin	default y
1168a5b9e5a2SAndy Lutomirski	depends on MODIFY_LDT_SYSCALL
116934273f41SH. Peter Anvin	---help---
117034273f41SH. Peter Anvin	  This option is required by programs like Wine to run 16-bit
117134273f41SH. Peter Anvin	  protected mode legacy code on x86 processors.  Disabling
117234273f41SH. Peter Anvin	  this option saves about 300 bytes on i386, or around 6K text
117334273f41SH. Peter Anvin	  plus 16K runtime memory on x86-64,
117434273f41SH. Peter Anvin
117534273f41SH. Peter Anvinconfig X86_ESPFIX32
117634273f41SH. Peter Anvin	def_bool y
117734273f41SH. Peter Anvin	depends on X86_16BIT && X86_32
1178506f1d07SSam Ravnborg
1179197725deSH. Peter Anvinconfig X86_ESPFIX64
1180197725deSH. Peter Anvin	def_bool y
118134273f41SH. Peter Anvin	depends on X86_16BIT && X86_64
1182506f1d07SSam Ravnborg
11831ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION
11841ad83c85SAndy Lutomirski       bool "Enable vsyscall emulation" if EXPERT
11851ad83c85SAndy Lutomirski       default y
11861ad83c85SAndy Lutomirski       depends on X86_64
11871ad83c85SAndy Lutomirski       ---help---
11881ad83c85SAndy Lutomirski	 This enables emulation of the legacy vsyscall page.  Disabling
11891ad83c85SAndy Lutomirski	 it is roughly equivalent to booting with vsyscall=none, except
11901ad83c85SAndy Lutomirski	 that it will also disable the helpful warning if a program
11911ad83c85SAndy Lutomirski	 tries to use a vsyscall.  With this option set to N, offending
11921ad83c85SAndy Lutomirski	 programs will just segfault, citing addresses of the form
11931ad83c85SAndy Lutomirski	 0xffffffffff600?00.
11941ad83c85SAndy Lutomirski
11951ad83c85SAndy Lutomirski	 This option is required by many programs built before 2013, and
11961ad83c85SAndy Lutomirski	 care should be used even with newer programs if set to N.
11971ad83c85SAndy Lutomirski
11981ad83c85SAndy Lutomirski	 Disabling this option saves about 7K of kernel size and
11991ad83c85SAndy Lutomirski	 possibly 4K of additional runtime pagetable memory.
12001ad83c85SAndy Lutomirski
1201506f1d07SSam Ravnborgconfig TOSHIBA
1202506f1d07SSam Ravnborg	tristate "Toshiba Laptop support"
1203506f1d07SSam Ravnborg	depends on X86_32
1204506f1d07SSam Ravnborg	---help---
1205506f1d07SSam Ravnborg	  This adds a driver to safely access the System Management Mode of
1206506f1d07SSam Ravnborg	  the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1207506f1d07SSam Ravnborg	  not work on models with a Phoenix BIOS. The System Management Mode
1208506f1d07SSam Ravnborg	  is used to set the BIOS and power saving options on Toshiba portables.
1209506f1d07SSam Ravnborg
1210506f1d07SSam Ravnborg	  For information on utilities to make use of this driver see the
1211506f1d07SSam Ravnborg	  Toshiba Linux utilities web site at:
1212506f1d07SSam Ravnborg	  <http://www.buzzard.org.uk/toshiba/>.
1213506f1d07SSam Ravnborg
1214506f1d07SSam Ravnborg	  Say Y if you intend to run this kernel on a Toshiba portable.
1215506f1d07SSam Ravnborg	  Say N otherwise.
1216506f1d07SSam Ravnborg
1217506f1d07SSam Ravnborgconfig I8K
1218039ae585SPali Rohár	tristate "Dell i8k legacy laptop support"
1219949a9d70SJean Delvare	select HWMON
1220039ae585SPali Rohár	select SENSORS_DELL_SMM
1221506f1d07SSam Ravnborg	---help---
1222039ae585SPali Rohár	  This option enables legacy /proc/i8k userspace interface in hwmon
1223039ae585SPali Rohár	  dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1224039ae585SPali Rohár	  temperature and allows controlling fan speeds of Dell laptops via
1225039ae585SPali Rohár	  System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1226039ae585SPali Rohár	  it reports also power and hotkey status. For fan speed control is
1227039ae585SPali Rohár	  needed userspace package i8kutils.
1228506f1d07SSam Ravnborg
1229039ae585SPali Rohár	  Say Y if you intend to run this kernel on old Dell laptops or want to
1230039ae585SPali Rohár	  use userspace package i8kutils.
1231506f1d07SSam Ravnborg	  Say N otherwise.
1232506f1d07SSam Ravnborg
1233506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS
12349ba16087SJan Beulich	bool "Enable X86 board specific fixups for reboot"
12359ba16087SJan Beulich	depends on X86_32
1236506f1d07SSam Ravnborg	---help---
1237506f1d07SSam Ravnborg	  This enables chipset and/or board specific fixups to be done
1238506f1d07SSam Ravnborg	  in order to get reboot to work correctly. This is only needed on
1239506f1d07SSam Ravnborg	  some combinations of hardware and BIOS. The symptom, for which
1240506f1d07SSam Ravnborg	  this config is intended, is when reboot ends with a stalled/hung
1241506f1d07SSam Ravnborg	  system.
1242506f1d07SSam Ravnborg
1243506f1d07SSam Ravnborg	  Currently, the only fixup is for the Geode machines using
12445e3a77e9SFlorian Fainelli	  CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1245506f1d07SSam Ravnborg
1246506f1d07SSam Ravnborg	  Say Y if you want to enable the fixup. Currently, it's safe to
1247506f1d07SSam Ravnborg	  enable this option even if you don't need it.
1248506f1d07SSam Ravnborg	  Say N otherwise.
1249506f1d07SSam Ravnborg
1250506f1d07SSam Ravnborgconfig MICROCODE
12519a2bc335SBorislav Petkov	bool "CPU microcode loading support"
12529a2bc335SBorislav Petkov	default y
125380030e3dSBorislav Petkov	depends on CPU_SUP_AMD || CPU_SUP_INTEL
1254506f1d07SSam Ravnborg	select FW_LOADER
1255506f1d07SSam Ravnborg	---help---
1256506f1d07SSam Ravnborg	  If you say Y here, you will be able to update the microcode on
12575f9c01aaSBorislav Petkov	  Intel and AMD processors. The Intel support is for the IA32 family,
12585f9c01aaSBorislav Petkov	  e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
12595f9c01aaSBorislav Petkov	  AMD support is for families 0x10 and later. You will obviously need
12605f9c01aaSBorislav Petkov	  the actual microcode binary data itself which is not shipped with
12615f9c01aaSBorislav Petkov	  the Linux kernel.
1262506f1d07SSam Ravnborg
12635f9c01aaSBorislav Petkov	  The preferred method to load microcode from a detached initrd is described
12645f9c01aaSBorislav Petkov	  in Documentation/x86/early-microcode.txt. For that you need to enable
12655f9c01aaSBorislav Petkov	  CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
12665f9c01aaSBorislav Petkov	  initrd for microcode blobs.
1267506f1d07SSam Ravnborg
12685f9c01aaSBorislav Petkov	  In addition, you can build-in the microcode into the kernel. For that you
12695f9c01aaSBorislav Petkov	  need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode
12705f9c01aaSBorislav Petkov	  to the CONFIG_EXTRA_FIRMWARE config option.
1271506f1d07SSam Ravnborg
12728d86f390SPeter Orubaconfig MICROCODE_INTEL
1273e43f6e67SBorislav Petkov	bool "Intel microcode loading support"
12748d86f390SPeter Oruba	depends on MICROCODE
12758d86f390SPeter Oruba	default MICROCODE
12768d86f390SPeter Oruba	select FW_LOADER
12778f9ca475SIngo Molnar	---help---
12788d86f390SPeter Oruba	  This options enables microcode patch loading support for Intel
12798d86f390SPeter Oruba	  processors.
12808d86f390SPeter Oruba
1281b8989db9SAlan	  For the current Intel microcode data package go to
1282b8989db9SAlan	  <https://downloadcenter.intel.com> and search for
1283b8989db9SAlan	  'Linux Processor Microcode Data File'.
12848d86f390SPeter Oruba
128580cc9f10SPeter Orubaconfig MICROCODE_AMD
1286e43f6e67SBorislav Petkov	bool "AMD microcode loading support"
128780cc9f10SPeter Oruba	depends on MICROCODE
128880cc9f10SPeter Oruba	select FW_LOADER
12898f9ca475SIngo Molnar	---help---
129080cc9f10SPeter Oruba	  If you select this option, microcode patch loading support for AMD
129180cc9f10SPeter Oruba	  processors will be enabled.
129280cc9f10SPeter Oruba
1293506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE
12943c2362e6SHarvey Harrison	def_bool y
1295506f1d07SSam Ravnborg	depends on MICROCODE
1296506f1d07SSam Ravnborg
1297506f1d07SSam Ravnborgconfig X86_MSR
1298506f1d07SSam Ravnborg	tristate "/dev/cpu/*/msr - Model-specific register support"
12998f9ca475SIngo Molnar	---help---
1300506f1d07SSam Ravnborg	  This device gives privileged processes access to the x86
1301506f1d07SSam Ravnborg	  Model-Specific Registers (MSRs).  It is a character device with
1302506f1d07SSam Ravnborg	  major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1303506f1d07SSam Ravnborg	  MSR accesses are directed to a specific CPU on multi-processor
1304506f1d07SSam Ravnborg	  systems.
1305506f1d07SSam Ravnborg
1306506f1d07SSam Ravnborgconfig X86_CPUID
1307506f1d07SSam Ravnborg	tristate "/dev/cpu/*/cpuid - CPU information support"
13088f9ca475SIngo Molnar	---help---
1309506f1d07SSam Ravnborg	  This device gives processes access to the x86 CPUID instruction to
1310506f1d07SSam Ravnborg	  be executed on a specific processor.  It is a character device
1311506f1d07SSam Ravnborg	  with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1312506f1d07SSam Ravnborg	  /dev/cpu/31/cpuid.
1313506f1d07SSam Ravnborg
1314506f1d07SSam Ravnborgchoice
1315506f1d07SSam Ravnborg	prompt "High Memory Support"
13166fc108a0SJan Beulich	default HIGHMEM4G
1317506f1d07SSam Ravnborg	depends on X86_32
1318506f1d07SSam Ravnborg
1319506f1d07SSam Ravnborgconfig NOHIGHMEM
1320506f1d07SSam Ravnborg	bool "off"
1321506f1d07SSam Ravnborg	---help---
1322506f1d07SSam Ravnborg	  Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1323506f1d07SSam Ravnborg	  However, the address space of 32-bit x86 processors is only 4
1324506f1d07SSam Ravnborg	  Gigabytes large. That means that, if you have a large amount of
1325506f1d07SSam Ravnborg	  physical memory, not all of it can be "permanently mapped" by the
1326506f1d07SSam Ravnborg	  kernel. The physical memory that's not permanently mapped is called
1327506f1d07SSam Ravnborg	  "high memory".
1328506f1d07SSam Ravnborg
1329506f1d07SSam Ravnborg	  If you are compiling a kernel which will never run on a machine with
1330506f1d07SSam Ravnborg	  more than 1 Gigabyte total physical RAM, answer "off" here (default
1331506f1d07SSam Ravnborg	  choice and suitable for most users). This will result in a "3GB/1GB"
1332506f1d07SSam Ravnborg	  split: 3GB are mapped so that each process sees a 3GB virtual memory
1333506f1d07SSam Ravnborg	  space and the remaining part of the 4GB virtual memory space is used
1334506f1d07SSam Ravnborg	  by the kernel to permanently map as much physical memory as
1335506f1d07SSam Ravnborg	  possible.
1336506f1d07SSam Ravnborg
1337506f1d07SSam Ravnborg	  If the machine has between 1 and 4 Gigabytes physical RAM, then
1338506f1d07SSam Ravnborg	  answer "4GB" here.
1339506f1d07SSam Ravnborg
1340506f1d07SSam Ravnborg	  If more than 4 Gigabytes is used then answer "64GB" here. This
1341506f1d07SSam Ravnborg	  selection turns Intel PAE (Physical Address Extension) mode on.
1342506f1d07SSam Ravnborg	  PAE implements 3-level paging on IA32 processors. PAE is fully
1343506f1d07SSam Ravnborg	  supported by Linux, PAE mode is implemented on all recent Intel
1344506f1d07SSam Ravnborg	  processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1345506f1d07SSam Ravnborg	  then the kernel will not boot on CPUs that don't support PAE!
1346506f1d07SSam Ravnborg
1347506f1d07SSam Ravnborg	  The actual amount of total physical memory will either be
1348506f1d07SSam Ravnborg	  auto detected or can be forced by using a kernel command line option
1349506f1d07SSam Ravnborg	  such as "mem=256M". (Try "man bootparam" or see the documentation of
1350506f1d07SSam Ravnborg	  your boot loader (lilo or loadlin) about how to pass options to the
1351506f1d07SSam Ravnborg	  kernel at boot time.)
1352506f1d07SSam Ravnborg
1353506f1d07SSam Ravnborg	  If unsure, say "off".
1354506f1d07SSam Ravnborg
1355506f1d07SSam Ravnborgconfig HIGHMEM4G
1356506f1d07SSam Ravnborg	bool "4GB"
13578f9ca475SIngo Molnar	---help---
1358506f1d07SSam Ravnborg	  Select this if you have a 32-bit processor and between 1 and 4
1359506f1d07SSam Ravnborg	  gigabytes of physical RAM.
1360506f1d07SSam Ravnborg
1361506f1d07SSam Ravnborgconfig HIGHMEM64G
1362506f1d07SSam Ravnborg	bool "64GB"
1363eb068e78SH. Peter Anvin	depends on !M486
1364506f1d07SSam Ravnborg	select X86_PAE
13658f9ca475SIngo Molnar	---help---
1366506f1d07SSam Ravnborg	  Select this if you have a 32-bit processor and more than 4
1367506f1d07SSam Ravnborg	  gigabytes of physical RAM.
1368506f1d07SSam Ravnborg
1369506f1d07SSam Ravnborgendchoice
1370506f1d07SSam Ravnborg
1371506f1d07SSam Ravnborgchoice
13726a108a14SDavid Rientjes	prompt "Memory split" if EXPERT
1373506f1d07SSam Ravnborg	default VMSPLIT_3G
1374506f1d07SSam Ravnborg	depends on X86_32
13758f9ca475SIngo Molnar	---help---
1376506f1d07SSam Ravnborg	  Select the desired split between kernel and user memory.
1377506f1d07SSam Ravnborg
1378506f1d07SSam Ravnborg	  If the address range available to the kernel is less than the
1379506f1d07SSam Ravnborg	  physical memory installed, the remaining memory will be available
1380506f1d07SSam Ravnborg	  as "high memory". Accessing high memory is a little more costly
1381506f1d07SSam Ravnborg	  than low memory, as it needs to be mapped into the kernel first.
1382506f1d07SSam Ravnborg	  Note that increasing the kernel address space limits the range
1383506f1d07SSam Ravnborg	  available to user programs, making the address space there
1384506f1d07SSam Ravnborg	  tighter.  Selecting anything other than the default 3G/1G split
1385506f1d07SSam Ravnborg	  will also likely make your kernel incompatible with binary-only
1386506f1d07SSam Ravnborg	  kernel modules.
1387506f1d07SSam Ravnborg
1388506f1d07SSam Ravnborg	  If you are not absolutely sure what you are doing, leave this
1389506f1d07SSam Ravnborg	  option alone!
1390506f1d07SSam Ravnborg
1391506f1d07SSam Ravnborg	config VMSPLIT_3G
1392506f1d07SSam Ravnborg		bool "3G/1G user/kernel split"
1393506f1d07SSam Ravnborg	config VMSPLIT_3G_OPT
1394506f1d07SSam Ravnborg		depends on !X86_PAE
1395506f1d07SSam Ravnborg		bool "3G/1G user/kernel split (for full 1G low memory)"
1396506f1d07SSam Ravnborg	config VMSPLIT_2G
1397506f1d07SSam Ravnborg		bool "2G/2G user/kernel split"
1398506f1d07SSam Ravnborg	config VMSPLIT_2G_OPT
1399506f1d07SSam Ravnborg		depends on !X86_PAE
1400506f1d07SSam Ravnborg		bool "2G/2G user/kernel split (for full 2G low memory)"
1401506f1d07SSam Ravnborg	config VMSPLIT_1G
1402506f1d07SSam Ravnborg		bool "1G/3G user/kernel split"
1403506f1d07SSam Ravnborgendchoice
1404506f1d07SSam Ravnborg
1405506f1d07SSam Ravnborgconfig PAGE_OFFSET
1406506f1d07SSam Ravnborg	hex
1407506f1d07SSam Ravnborg	default 0xB0000000 if VMSPLIT_3G_OPT
1408506f1d07SSam Ravnborg	default 0x80000000 if VMSPLIT_2G
1409506f1d07SSam Ravnborg	default 0x78000000 if VMSPLIT_2G_OPT
1410506f1d07SSam Ravnborg	default 0x40000000 if VMSPLIT_1G
1411506f1d07SSam Ravnborg	default 0xC0000000
1412506f1d07SSam Ravnborg	depends on X86_32
1413506f1d07SSam Ravnborg
1414506f1d07SSam Ravnborgconfig HIGHMEM
14153c2362e6SHarvey Harrison	def_bool y
1416506f1d07SSam Ravnborg	depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1417506f1d07SSam Ravnborg
1418506f1d07SSam Ravnborgconfig X86_PAE
14199ba16087SJan Beulich	bool "PAE (Physical Address Extension) Support"
1420506f1d07SSam Ravnborg	depends on X86_32 && !HIGHMEM4G
14219d99c712SChristian Melki	select SWIOTLB
14228f9ca475SIngo Molnar	---help---
1423506f1d07SSam Ravnborg	  PAE is required for NX support, and furthermore enables
1424506f1d07SSam Ravnborg	  larger swapspace support for non-overcommit purposes. It
1425506f1d07SSam Ravnborg	  has the cost of more pagetable lookup overhead, and also
1426506f1d07SSam Ravnborg	  consumes more pagetable space per process.
1427506f1d07SSam Ravnborg
142877ef56e4SKirill A. Shutemovconfig X86_5LEVEL
142977ef56e4SKirill A. Shutemov	bool "Enable 5-level page tables support"
143077ef56e4SKirill A. Shutemov	depends on X86_64
143177ef56e4SKirill A. Shutemov	---help---
143277ef56e4SKirill A. Shutemov	  5-level paging enables access to larger address space:
143377ef56e4SKirill A. Shutemov	  upto 128 PiB of virtual address space and 4 PiB of
143477ef56e4SKirill A. Shutemov	  physical address space.
143577ef56e4SKirill A. Shutemov
143677ef56e4SKirill A. Shutemov	  It will be supported by future Intel CPUs.
143777ef56e4SKirill A. Shutemov
143877ef56e4SKirill A. Shutemov	  Note: a kernel with this option enabled can only be booted
143977ef56e4SKirill A. Shutemov	  on machines that support the feature.
144077ef56e4SKirill A. Shutemov
144177ef56e4SKirill A. Shutemov	  See Documentation/x86/x86_64/5level-paging.txt for more
144277ef56e4SKirill A. Shutemov	  information.
144377ef56e4SKirill A. Shutemov
144477ef56e4SKirill A. Shutemov	  Say N if unsure.
144577ef56e4SKirill A. Shutemov
1446600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT
14473120e25eSJan Beulich	def_bool y
14483120e25eSJan Beulich	depends on X86_64 || X86_PAE
1449600715dcSJeremy Fitzhardinge
145066f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT
14513120e25eSJan Beulich	def_bool y
14523120e25eSJan Beulich	depends on X86_64 || HIGHMEM64G
145366f2b061SFUJITA Tomonori
145410971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES
1455e5008abeSLuis R. Rodriguez	def_bool y
14564675ff05SLevin, Alexander (Sasha Levin)	depends on X86_64 && !DEBUG_PAGEALLOC
14578f9ca475SIngo Molnar	---help---
145810971ab2SIngo Molnar	  Certain kernel features effectively disable kernel
145910971ab2SIngo Molnar	  linear 1 GB mappings (even if the CPU otherwise
146010971ab2SIngo Molnar	  supports them), so don't confuse the user by printing
146110971ab2SIngo Molnar	  that we have them enabled.
14629e899816SNick Piggin
14637744ccdbSTom Lendackyconfig ARCH_HAS_MEM_ENCRYPT
14647744ccdbSTom Lendacky	def_bool y
14657744ccdbSTom Lendacky
14667744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT
14677744ccdbSTom Lendacky	bool "AMD Secure Memory Encryption (SME) support"
14687744ccdbSTom Lendacky	depends on X86_64 && CPU_SUP_AMD
14697744ccdbSTom Lendacky	---help---
14707744ccdbSTom Lendacky	  Say yes to enable support for the encryption of system memory.
14717744ccdbSTom Lendacky	  This requires an AMD processor that supports Secure Memory
14727744ccdbSTom Lendacky	  Encryption (SME).
14737744ccdbSTom Lendacky
14747744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
14757744ccdbSTom Lendacky	bool "Activate AMD Secure Memory Encryption (SME) by default"
14767744ccdbSTom Lendacky	default y
14777744ccdbSTom Lendacky	depends on AMD_MEM_ENCRYPT
14787744ccdbSTom Lendacky	---help---
14797744ccdbSTom Lendacky	  Say yes to have system memory encrypted by default if running on
14807744ccdbSTom Lendacky	  an AMD processor that supports Secure Memory Encryption (SME).
14817744ccdbSTom Lendacky
14827744ccdbSTom Lendacky	  If set to Y, then the encryption of system memory can be
14837744ccdbSTom Lendacky	  deactivated with the mem_encrypt=off command line option.
14847744ccdbSTom Lendacky
14857744ccdbSTom Lendacky	  If set to N, then the encryption of system memory can be
14867744ccdbSTom Lendacky	  activated with the mem_encrypt=on command line option.
14877744ccdbSTom Lendacky
1488f88a68faSTom Lendackyconfig ARCH_USE_MEMREMAP_PROT
1489f88a68faSTom Lendacky	def_bool y
1490f88a68faSTom Lendacky	depends on AMD_MEM_ENCRYPT
1491f88a68faSTom Lendacky
1492506f1d07SSam Ravnborg# Common NUMA Features
1493506f1d07SSam Ravnborgconfig NUMA
1494fd51b2d7SKOSAKI Motohiro	bool "Numa Memory Allocation and Scheduler Support"
1495506f1d07SSam Ravnborg	depends on SMP
1496b5660ba7SH. Peter Anvin	depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1497b5660ba7SH. Peter Anvin	default y if X86_BIGSMP
14988f9ca475SIngo Molnar	---help---
1499506f1d07SSam Ravnborg	  Enable NUMA (Non Uniform Memory Access) support.
1500fd51b2d7SKOSAKI Motohiro
1501506f1d07SSam Ravnborg	  The kernel will try to allocate memory used by a CPU on the
1502506f1d07SSam Ravnborg	  local memory controller of the CPU and add some more
1503506f1d07SSam Ravnborg	  NUMA awareness to the kernel.
1504506f1d07SSam Ravnborg
1505c280ea5eSIngo Molnar	  For 64-bit this is recommended if the system is Intel Core i7
1506fd51b2d7SKOSAKI Motohiro	  (or later), AMD Opteron, or EM64T NUMA.
1507fd51b2d7SKOSAKI Motohiro
1508b5660ba7SH. Peter Anvin	  For 32-bit this is only needed if you boot a 32-bit
15097cf6c945SDavid Rientjes	  kernel on a 64-bit NUMA platform.
1510fd51b2d7SKOSAKI Motohiro
1511fd51b2d7SKOSAKI Motohiro	  Otherwise, you should say N.
1512506f1d07SSam Ravnborg
1513eec1d4faSHans Rosenfeldconfig AMD_NUMA
15143c2362e6SHarvey Harrison	def_bool y
15153c2362e6SHarvey Harrison	prompt "Old style AMD Opteron NUMA detection"
15165da0ef9aSTejun Heo	depends on X86_64 && NUMA && PCI
15178f9ca475SIngo Molnar	---help---
1518eec1d4faSHans Rosenfeld	  Enable AMD NUMA node topology detection.  You should say Y here if
1519eec1d4faSHans Rosenfeld	  you have a multi processor AMD system. This uses an old method to
1520eec1d4faSHans Rosenfeld	  read the NUMA configuration directly from the builtin Northbridge
1521eec1d4faSHans Rosenfeld	  of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1522eec1d4faSHans Rosenfeld	  which also takes priority if both are compiled in.
1523506f1d07SSam Ravnborg
1524506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA
15253c2362e6SHarvey Harrison	def_bool y
15263c2362e6SHarvey Harrison	prompt "ACPI NUMA detection"
1527506f1d07SSam Ravnborg	depends on X86_64 && NUMA && ACPI && PCI
1528506f1d07SSam Ravnborg	select ACPI_NUMA
15298f9ca475SIngo Molnar	---help---
1530506f1d07SSam Ravnborg	  Enable ACPI SRAT based node topology detection.
1531506f1d07SSam Ravnborg
15326ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span
15336ec6e0d9SSuresh Siddha# other nodes.  Even though a pfn is valid and
15346ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not
15356ec6e0d9SSuresh Siddha# reside on that node.  See memmap_init_zone()
15366ec6e0d9SSuresh Siddha# for details.
15376ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES
15386ec6e0d9SSuresh Siddha	def_bool y
15396ec6e0d9SSuresh Siddha	depends on X86_64_ACPI_NUMA
15406ec6e0d9SSuresh Siddha
1541506f1d07SSam Ravnborgconfig NUMA_EMU
1542506f1d07SSam Ravnborg	bool "NUMA emulation"
15431b7e03efSTejun Heo	depends on NUMA
15448f9ca475SIngo Molnar	---help---
1545506f1d07SSam Ravnborg	  Enable NUMA emulation. A flat machine will be split
1546506f1d07SSam Ravnborg	  into virtual nodes when booted with "numa=fake=N", where N is the
1547506f1d07SSam Ravnborg	  number of nodes. This is only useful for debugging.
1548506f1d07SSam Ravnborg
1549506f1d07SSam Ravnborgconfig NODES_SHIFT
1550d25e26b6SLinus Torvalds	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
155151591e31SDavid Rientjes	range 1 10
155251591e31SDavid Rientjes	default "10" if MAXSMP
1553506f1d07SSam Ravnborg	default "6" if X86_64
1554506f1d07SSam Ravnborg	default "3"
1555506f1d07SSam Ravnborg	depends on NEED_MULTIPLE_NODES
15568f9ca475SIngo Molnar	---help---
15571184dc2fSMike Travis	  Specify the maximum number of NUMA Nodes available on the target
1558692105b8SMatt LaPlante	  system.  Increases memory reserved to accommodate various tables.
1559506f1d07SSam Ravnborg
1560506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT
15613c2362e6SHarvey Harrison	def_bool y
1562506f1d07SSam Ravnborg	depends on X86_32 && DISCONTIGMEM
1563506f1d07SSam Ravnborg
1564506f1d07SSam Ravnborgconfig NEED_NODE_MEMMAP_SIZE
15653c2362e6SHarvey Harrison	def_bool y
1566506f1d07SSam Ravnborg	depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1567506f1d07SSam Ravnborg
1568506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE
1569506f1d07SSam Ravnborg	def_bool y
15703b16651fSTejun Heo	depends on X86_32 && !NUMA
1571506f1d07SSam Ravnborg
1572506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE
1573506f1d07SSam Ravnborg	def_bool y
1574b263295dSChristoph Lameter	depends on NUMA && X86_32
1575506f1d07SSam Ravnborg
1576506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT
1577506f1d07SSam Ravnborg	def_bool y
1578b263295dSChristoph Lameter	depends on NUMA && X86_32
1579b263295dSChristoph Lameter
1580506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE
1581506f1d07SSam Ravnborg	def_bool y
15826ea30386SKees Cook	depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1583506f1d07SSam Ravnborg	select SPARSEMEM_STATIC if X86_32
1584506f1d07SSam Ravnborg	select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1585506f1d07SSam Ravnborg
15863b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT
15873b16651fSTejun Heo	def_bool y
15883b16651fSTejun Heo	depends on X86_64
15893b16651fSTejun Heo
1590506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL
1591506f1d07SSam Ravnborg	def_bool y
1592b263295dSChristoph Lameter	depends on ARCH_SPARSEMEM_ENABLE
1593506f1d07SSam Ravnborg
1594506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE
1595a0842b70SToshi Kani	bool "Enable sysfs memory/probe interface"
15963120e25eSJan Beulich	depends on X86_64 && MEMORY_HOTPLUG
1597a0842b70SToshi Kani	help
1598a0842b70SToshi Kani	  This option enables a sysfs memory/probe interface for testing.
1599a0842b70SToshi Kani	  See Documentation/memory-hotplug.txt for more information.
1600a0842b70SToshi Kani	  If you are unsure how to answer this question, answer N.
1601506f1d07SSam Ravnborg
16023b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT
16033b16651fSTejun Heo	def_bool y
16043b16651fSTejun Heo	depends on X86_64 && PROC_KCORE
16053b16651fSTejun Heo
1606a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE
1607a29815a3SAvi Kivity       hex
1608a29815a3SAvi Kivity       default 0 if X86_32
1609a29815a3SAvi Kivity       default 0xdead000000000000 if X86_64
1610a29815a3SAvi Kivity
1611506f1d07SSam Ravnborgsource "mm/Kconfig"
1612506f1d07SSam Ravnborg
16137a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE
16147a67832cSDan Williams	bool
16157a67832cSDan Williams
1616ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY
16177a67832cSDan Williams	tristate "Support non-standard NVDIMMs and ADR protected memory"
16189f53f9faSDan Williams	depends on PHYS_ADDR_T_64BIT
16199f53f9faSDan Williams	depends on BLK_DEV
16207a67832cSDan Williams	select X86_PMEM_LEGACY_DEVICE
16219f53f9faSDan Williams	select LIBNVDIMM
1622ec776ef6SChristoph Hellwig	help
1623ec776ef6SChristoph Hellwig	  Treat memory marked using the non-standard e820 type of 12 as used
1624ec776ef6SChristoph Hellwig	  by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1625ec776ef6SChristoph Hellwig	  The kernel will offer these regions to the 'pmem' driver so
1626ec776ef6SChristoph Hellwig	  they can be used for persistent storage.
1627ec776ef6SChristoph Hellwig
1628ec776ef6SChristoph Hellwig	  Say Y if unsure.
1629ec776ef6SChristoph Hellwig
1630506f1d07SSam Ravnborgconfig HIGHPTE
1631506f1d07SSam Ravnborg	bool "Allocate 3rd-level pagetables from highmem"
16326fc108a0SJan Beulich	depends on HIGHMEM
16338f9ca475SIngo Molnar	---help---
1634506f1d07SSam Ravnborg	  The VM uses one page table entry for each page of physical memory.
1635506f1d07SSam Ravnborg	  For systems with a lot of RAM, this can be wasteful of precious
1636506f1d07SSam Ravnborg	  low memory.  Setting this option will put user-space page table
1637506f1d07SSam Ravnborg	  entries in high memory.
1638506f1d07SSam Ravnborg
16399f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION
16409f077871SJeremy Fitzhardinge	bool "Check for low memory corruption"
16418f9ca475SIngo Molnar	---help---
16429f077871SJeremy Fitzhardinge	  Periodically check for memory corruption in low memory, which
16439f077871SJeremy Fitzhardinge	  is suspected to be caused by BIOS.  Even when enabled in the
16449f077871SJeremy Fitzhardinge	  configuration, it is disabled at runtime.  Enable it by
16459f077871SJeremy Fitzhardinge	  setting "memory_corruption_check=1" on the kernel command
16469f077871SJeremy Fitzhardinge	  line.  By default it scans the low 64k of memory every 60
16479f077871SJeremy Fitzhardinge	  seconds; see the memory_corruption_check_size and
16489f077871SJeremy Fitzhardinge	  memory_corruption_check_period parameters in
16498c27ceffSMauro Carvalho Chehab	  Documentation/admin-guide/kernel-parameters.rst to adjust this.
16509f077871SJeremy Fitzhardinge
16519f077871SJeremy Fitzhardinge	  When enabled with the default parameters, this option has
16529f077871SJeremy Fitzhardinge	  almost no overhead, as it reserves a relatively small amount
16539f077871SJeremy Fitzhardinge	  of memory and scans it infrequently.  It both detects corruption
16549f077871SJeremy Fitzhardinge	  and prevents it from affecting the running system.
16559f077871SJeremy Fitzhardinge
16569f077871SJeremy Fitzhardinge	  It is, however, intended as a diagnostic tool; if repeatable
16579f077871SJeremy Fitzhardinge	  BIOS-originated corruption always affects the same memory,
16589f077871SJeremy Fitzhardinge	  you can use memmap= to prevent the kernel from using that
16599f077871SJeremy Fitzhardinge	  memory.
16609f077871SJeremy Fitzhardinge
1661c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1662c885df50SJeremy Fitzhardinge	bool "Set the default setting of memory_corruption_check"
1663c885df50SJeremy Fitzhardinge	depends on X86_CHECK_BIOS_CORRUPTION
1664c885df50SJeremy Fitzhardinge	default y
16658f9ca475SIngo Molnar	---help---
1666c885df50SJeremy Fitzhardinge	  Set whether the default state of memory_corruption_check is
1667c885df50SJeremy Fitzhardinge	  on or off.
1668c885df50SJeremy Fitzhardinge
16699ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW
1670d0cd7425SH. Peter Anvin	int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1671d0cd7425SH. Peter Anvin	default 64
1672d0cd7425SH. Peter Anvin	range 4 640
16738f9ca475SIngo Molnar	---help---
1674d0cd7425SH. Peter Anvin	  Specify the amount of low memory to reserve for the BIOS.
1675fc381519SIngo Molnar
1676d0cd7425SH. Peter Anvin	  The first page contains BIOS data structures that the kernel
1677d0cd7425SH. Peter Anvin	  must not use, so that page must always be reserved.
1678fc381519SIngo Molnar
1679d0cd7425SH. Peter Anvin	  By default we reserve the first 64K of physical RAM, as a
1680d0cd7425SH. Peter Anvin	  number of BIOSes are known to corrupt that memory range
1681d0cd7425SH. Peter Anvin	  during events such as suspend/resume or monitor cable
1682d0cd7425SH. Peter Anvin	  insertion, so it must not be used by the kernel.
1683fc381519SIngo Molnar
1684d0cd7425SH. Peter Anvin	  You can set this to 4 if you are absolutely sure that you
1685d0cd7425SH. Peter Anvin	  trust the BIOS to get all its memory reservations and usages
1686d0cd7425SH. Peter Anvin	  right.  If you know your BIOS have problems beyond the
1687d0cd7425SH. Peter Anvin	  default 64K area, you can set this to 640 to avoid using the
1688d0cd7425SH. Peter Anvin	  entire low memory range.
1689d0cd7425SH. Peter Anvin
1690d0cd7425SH. Peter Anvin	  If you have doubts about the BIOS (e.g. suspend/resume does
1691d0cd7425SH. Peter Anvin	  not work or there's kernel crashes after certain hardware
1692d0cd7425SH. Peter Anvin	  hotplug events) then you might want to enable
1693d0cd7425SH. Peter Anvin	  X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1694d0cd7425SH. Peter Anvin	  typical corruption patterns.
1695d0cd7425SH. Peter Anvin
1696d0cd7425SH. Peter Anvin	  Leave this to the default value of 64 if you are unsure.
1697fc381519SIngo Molnar
1698506f1d07SSam Ravnborgconfig MATH_EMULATION
1699506f1d07SSam Ravnborg	bool
1700a5b9e5a2SAndy Lutomirski	depends on MODIFY_LDT_SYSCALL
1701506f1d07SSam Ravnborg	prompt "Math emulation" if X86_32
1702506f1d07SSam Ravnborg	---help---
1703506f1d07SSam Ravnborg	  Linux can emulate a math coprocessor (used for floating point
1704506f1d07SSam Ravnborg	  operations) if you don't have one. 486DX and Pentium processors have
1705506f1d07SSam Ravnborg	  a math coprocessor built in, 486SX and 386 do not, unless you added
1706506f1d07SSam Ravnborg	  a 487DX or 387, respectively. (The messages during boot time can
1707506f1d07SSam Ravnborg	  give you some hints here ["man dmesg"].) Everyone needs either a
1708506f1d07SSam Ravnborg	  coprocessor or this emulation.
1709506f1d07SSam Ravnborg
1710506f1d07SSam Ravnborg	  If you don't have a math coprocessor, you need to say Y here; if you
1711506f1d07SSam Ravnborg	  say Y here even though you have a coprocessor, the coprocessor will
1712506f1d07SSam Ravnborg	  be used nevertheless. (This behavior can be changed with the kernel
1713506f1d07SSam Ravnborg	  command line option "no387", which comes handy if your coprocessor
1714506f1d07SSam Ravnborg	  is broken. Try "man bootparam" or see the documentation of your boot
1715506f1d07SSam Ravnborg	  loader (lilo or loadlin) about how to pass options to the kernel at
1716506f1d07SSam Ravnborg	  boot time.) This means that it is a good idea to say Y here if you
1717506f1d07SSam Ravnborg	  intend to use this kernel on different machines.
1718506f1d07SSam Ravnborg
1719506f1d07SSam Ravnborg	  More information about the internals of the Linux math coprocessor
1720506f1d07SSam Ravnborg	  emulation can be found in <file:arch/x86/math-emu/README>.
1721506f1d07SSam Ravnborg
1722506f1d07SSam Ravnborg	  If you are not sure, say Y; apart from resulting in a 66 KB bigger
1723506f1d07SSam Ravnborg	  kernel, it won't hurt.
1724506f1d07SSam Ravnborg
1725506f1d07SSam Ravnborgconfig MTRR
17266fc108a0SJan Beulich	def_bool y
17276a108a14SDavid Rientjes	prompt "MTRR (Memory Type Range Register) support" if EXPERT
1728506f1d07SSam Ravnborg	---help---
1729506f1d07SSam Ravnborg	  On Intel P6 family processors (Pentium Pro, Pentium II and later)
1730506f1d07SSam Ravnborg	  the Memory Type Range Registers (MTRRs) may be used to control
1731506f1d07SSam Ravnborg	  processor access to memory ranges. This is most useful if you have
1732506f1d07SSam Ravnborg	  a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1733506f1d07SSam Ravnborg	  allows bus write transfers to be combined into a larger transfer
1734506f1d07SSam Ravnborg	  before bursting over the PCI/AGP bus. This can increase performance
1735506f1d07SSam Ravnborg	  of image write operations 2.5 times or more. Saying Y here creates a
1736506f1d07SSam Ravnborg	  /proc/mtrr file which may be used to manipulate your processor's
1737506f1d07SSam Ravnborg	  MTRRs. Typically the X server should use this.
1738506f1d07SSam Ravnborg
1739506f1d07SSam Ravnborg	  This code has a reasonably generic interface so that similar
1740506f1d07SSam Ravnborg	  control registers on other processors can be easily supported
1741506f1d07SSam Ravnborg	  as well:
1742506f1d07SSam Ravnborg
1743506f1d07SSam Ravnborg	  The Cyrix 6x86, 6x86MX and M II processors have Address Range
1744506f1d07SSam Ravnborg	  Registers (ARRs) which provide a similar functionality to MTRRs. For
1745506f1d07SSam Ravnborg	  these, the ARRs are used to emulate the MTRRs.
1746506f1d07SSam Ravnborg	  The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1747506f1d07SSam Ravnborg	  MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1748506f1d07SSam Ravnborg	  write-combining. All of these processors are supported by this code
1749506f1d07SSam Ravnborg	  and it makes sense to say Y here if you have one of them.
1750506f1d07SSam Ravnborg
1751506f1d07SSam Ravnborg	  Saying Y here also fixes a problem with buggy SMP BIOSes which only
1752506f1d07SSam Ravnborg	  set the MTRRs for the boot CPU and not for the secondary CPUs. This
1753506f1d07SSam Ravnborg	  can lead to all sorts of problems, so it's good to say Y here.
1754506f1d07SSam Ravnborg
1755506f1d07SSam Ravnborg	  You can safely say Y even if your machine doesn't have MTRRs, you'll
1756506f1d07SSam Ravnborg	  just add about 9 KB to your kernel.
1757506f1d07SSam Ravnborg
17587225e751SRandy Dunlap	  See <file:Documentation/x86/mtrr.txt> for more information.
1759506f1d07SSam Ravnborg
176095ffa243SYinghai Luconfig MTRR_SANITIZER
17612ffb3501SYinghai Lu	def_bool y
176295ffa243SYinghai Lu	prompt "MTRR cleanup support"
176395ffa243SYinghai Lu	depends on MTRR
17648f9ca475SIngo Molnar	---help---
1765aba3728cSThomas Gleixner	  Convert MTRR layout from continuous to discrete, so X drivers can
1766aba3728cSThomas Gleixner	  add writeback entries.
176795ffa243SYinghai Lu
1768aba3728cSThomas Gleixner	  Can be disabled with disable_mtrr_cleanup on the kernel command line.
1769692105b8SMatt LaPlante	  The largest mtrr entry size for a continuous block can be set with
1770aba3728cSThomas Gleixner	  mtrr_chunk_size.
177195ffa243SYinghai Lu
17722ffb3501SYinghai Lu	  If unsure, say Y.
177395ffa243SYinghai Lu
177495ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT
1775f5098d62SYinghai Lu	int "MTRR cleanup enable value (0-1)"
1776f5098d62SYinghai Lu	range 0 1
1777f5098d62SYinghai Lu	default "0"
177895ffa243SYinghai Lu	depends on MTRR_SANITIZER
17798f9ca475SIngo Molnar	---help---
1780f5098d62SYinghai Lu	  Enable mtrr cleanup default value
178195ffa243SYinghai Lu
178212031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
178312031a62SYinghai Lu	int "MTRR cleanup spare reg num (0-7)"
178412031a62SYinghai Lu	range 0 7
178512031a62SYinghai Lu	default "1"
178612031a62SYinghai Lu	depends on MTRR_SANITIZER
17878f9ca475SIngo Molnar	---help---
178812031a62SYinghai Lu	  mtrr cleanup spare entries default, it can be changed via
1789aba3728cSThomas Gleixner	  mtrr_spare_reg_nr=N on the kernel command line.
179012031a62SYinghai Lu
17912e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT
17926fc108a0SJan Beulich	def_bool y
17936a108a14SDavid Rientjes	prompt "x86 PAT support" if EXPERT
17942a8a2719SIngo Molnar	depends on MTRR
17958f9ca475SIngo Molnar	---help---
17962e5d9c85Svenkatesh.pallipadi@intel.com	  Use PAT attributes to setup page level cache control.
1797042b78e4SVenki Pallipadi
17982e5d9c85Svenkatesh.pallipadi@intel.com	  PATs are the modern equivalents of MTRRs and are much more
17992e5d9c85Svenkatesh.pallipadi@intel.com	  flexible than MTRRs.
18002e5d9c85Svenkatesh.pallipadi@intel.com
18012e5d9c85Svenkatesh.pallipadi@intel.com	  Say N here if you see bootup problems (boot crash, boot hang,
1802042b78e4SVenki Pallipadi	  spontaneous reboots) or a non-working video driver.
18032e5d9c85Svenkatesh.pallipadi@intel.com
18042e5d9c85Svenkatesh.pallipadi@intel.com	  If unsure, say Y.
18052e5d9c85Svenkatesh.pallipadi@intel.com
180646cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED
180746cf98cdSVenkatesh Pallipadi	def_bool y
180846cf98cdSVenkatesh Pallipadi	depends on X86_PAT
180946cf98cdSVenkatesh Pallipadi
1810628c6246SH. Peter Anvinconfig ARCH_RANDOM
1811628c6246SH. Peter Anvin	def_bool y
1812628c6246SH. Peter Anvin	prompt "x86 architectural random number generator" if EXPERT
1813628c6246SH. Peter Anvin	---help---
1814628c6246SH. Peter Anvin	  Enable the x86 architectural RDRAND instruction
1815628c6246SH. Peter Anvin	  (Intel Bull Mountain technology) to generate random numbers.
1816628c6246SH. Peter Anvin	  If supported, this is a high bandwidth, cryptographically
1817628c6246SH. Peter Anvin	  secure hardware random number generator.
1818628c6246SH. Peter Anvin
181951ae4a2dSH. Peter Anvinconfig X86_SMAP
182051ae4a2dSH. Peter Anvin	def_bool y
182151ae4a2dSH. Peter Anvin	prompt "Supervisor Mode Access Prevention" if EXPERT
182251ae4a2dSH. Peter Anvin	---help---
182351ae4a2dSH. Peter Anvin	  Supervisor Mode Access Prevention (SMAP) is a security
182451ae4a2dSH. Peter Anvin	  feature in newer Intel processors.  There is a small
182551ae4a2dSH. Peter Anvin	  performance cost if this enabled and turned on; there is
182651ae4a2dSH. Peter Anvin	  also a small increase in the kernel size if this is enabled.
182751ae4a2dSH. Peter Anvin
182851ae4a2dSH. Peter Anvin	  If unsure, say Y.
182951ae4a2dSH. Peter Anvin
1830aa35f896SRicardo Nericonfig X86_INTEL_UMIP
1831796ebc81SRicardo Neri	def_bool y
1832aa35f896SRicardo Neri	depends on CPU_SUP_INTEL
1833aa35f896SRicardo Neri	prompt "Intel User Mode Instruction Prevention" if EXPERT
1834aa35f896SRicardo Neri	---help---
1835aa35f896SRicardo Neri	  The User Mode Instruction Prevention (UMIP) is a security
1836aa35f896SRicardo Neri	  feature in newer Intel processors. If enabled, a general
1837796ebc81SRicardo Neri	  protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1838796ebc81SRicardo Neri	  or STR instructions are executed in user mode. These instructions
1839796ebc81SRicardo Neri	  unnecessarily expose information about the hardware state.
1840796ebc81SRicardo Neri
1841796ebc81SRicardo Neri	  The vast majority of applications do not use these instructions.
1842796ebc81SRicardo Neri	  For the very few that do, software emulation is provided in
1843796ebc81SRicardo Neri	  specific cases in protected and virtual-8086 modes. Emulated
1844796ebc81SRicardo Neri	  results are dummy.
1845aa35f896SRicardo Neri
184672e9b5feSDave Hansenconfig X86_INTEL_MPX
184772e9b5feSDave Hansen	prompt "Intel MPX (Memory Protection Extensions)"
184872e9b5feSDave Hansen	def_bool n
1849df3735c5SRik van Riel	# Note: only available in 64-bit mode due to VMA flags shortage
1850df3735c5SRik van Riel	depends on CPU_SUP_INTEL && X86_64
1851df3735c5SRik van Riel	select ARCH_USES_HIGH_VMA_FLAGS
185272e9b5feSDave Hansen	---help---
185372e9b5feSDave Hansen	  MPX provides hardware features that can be used in
185472e9b5feSDave Hansen	  conjunction with compiler-instrumented code to check
185572e9b5feSDave Hansen	  memory references.  It is designed to detect buffer
185672e9b5feSDave Hansen	  overflow or underflow bugs.
185772e9b5feSDave Hansen
185872e9b5feSDave Hansen	  This option enables running applications which are
185972e9b5feSDave Hansen	  instrumented or otherwise use MPX.  It does not use MPX
186072e9b5feSDave Hansen	  itself inside the kernel or to protect the kernel
186172e9b5feSDave Hansen	  against bad memory references.
186272e9b5feSDave Hansen
186372e9b5feSDave Hansen	  Enabling this option will make the kernel larger:
186472e9b5feSDave Hansen	  ~8k of kernel text and 36 bytes of data on a 64-bit
186572e9b5feSDave Hansen	  defconfig.  It adds a long to the 'mm_struct' which
186672e9b5feSDave Hansen	  will increase the kernel memory overhead of each
186772e9b5feSDave Hansen	  process and adds some branches to paths used during
186872e9b5feSDave Hansen	  exec() and munmap().
186972e9b5feSDave Hansen
187072e9b5feSDave Hansen	  For details, see Documentation/x86/intel_mpx.txt
187172e9b5feSDave Hansen
187272e9b5feSDave Hansen	  If unsure, say N.
187372e9b5feSDave Hansen
187435e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS
1875284244a9SDave Hansen	prompt "Intel Memory Protection Keys"
187635e97790SDave Hansen	def_bool y
1877284244a9SDave Hansen	# Note: only available in 64-bit mode
187835e97790SDave Hansen	depends on CPU_SUP_INTEL && X86_64
187952c8e601SIngo Molnar	select ARCH_USES_HIGH_VMA_FLAGS
188052c8e601SIngo Molnar	select ARCH_HAS_PKEYS
1881284244a9SDave Hansen	---help---
1882284244a9SDave Hansen	  Memory Protection Keys provides a mechanism for enforcing
1883284244a9SDave Hansen	  page-based protections, but without requiring modification of the
1884284244a9SDave Hansen	  page tables when an application changes protection domains.
1885284244a9SDave Hansen
1886284244a9SDave Hansen	  For details, see Documentation/x86/protection-keys.txt
1887284244a9SDave Hansen
1888284244a9SDave Hansen	  If unsure, say y.
188935e97790SDave Hansen
1890506f1d07SSam Ravnborgconfig EFI
18919ba16087SJan Beulich	bool "EFI runtime service support"
18925b83683fSHuang, Ying	depends on ACPI
1893f6ce5002SSergey Vlasov	select UCS2_STRING
1894022ee6c5SArd Biesheuvel	select EFI_RUNTIME_WRAPPERS
1895506f1d07SSam Ravnborg	---help---
18968b2cb7a8SHuang, Ying	  This enables the kernel to use EFI runtime services that are
1897506f1d07SSam Ravnborg	  available (such as the EFI variable services).
1898506f1d07SSam Ravnborg
18998b2cb7a8SHuang, Ying	  This option is only useful on systems that have EFI firmware.
19008b2cb7a8SHuang, Ying	  In addition, you should use the latest ELILO loader available
19018b2cb7a8SHuang, Ying	  at <http://elilo.sourceforge.net> in order to take advantage
19028b2cb7a8SHuang, Ying	  of EFI runtime services. However, even with this option, the
19038b2cb7a8SHuang, Ying	  resultant kernel should continue to boot on existing non-EFI
19048b2cb7a8SHuang, Ying	  platforms.
1905506f1d07SSam Ravnborg
1906291f3632SMatt Flemingconfig EFI_STUB
1907291f3632SMatt Fleming       bool "EFI stub support"
1908b16d8c23SMatt Fleming       depends on EFI && !X86_USE_3DNOW
19097b2a583aSMatt Fleming       select RELOCATABLE
1910291f3632SMatt Fleming       ---help---
1911291f3632SMatt Fleming          This kernel feature allows a bzImage to be loaded directly
1912291f3632SMatt Fleming	  by EFI firmware without the use of a bootloader.
1913291f3632SMatt Fleming
19144172fe2fSRoy Franz	  See Documentation/efi-stub.txt for more information.
19150c759662SMatt Fleming
19167d453eeeSMatt Flemingconfig EFI_MIXED
19177d453eeeSMatt Fleming	bool "EFI mixed-mode support"
19187d453eeeSMatt Fleming	depends on EFI_STUB && X86_64
19197d453eeeSMatt Fleming	---help---
19207d453eeeSMatt Fleming	   Enabling this feature allows a 64-bit kernel to be booted
19217d453eeeSMatt Fleming	   on a 32-bit firmware, provided that your CPU supports 64-bit
19227d453eeeSMatt Fleming	   mode.
19237d453eeeSMatt Fleming
19247d453eeeSMatt Fleming	   Note that it is not possible to boot a mixed-mode enabled
19257d453eeeSMatt Fleming	   kernel via the EFI boot stub - a bootloader that supports
19267d453eeeSMatt Fleming	   the EFI handover protocol must be used.
19277d453eeeSMatt Fleming
19287d453eeeSMatt Fleming	   If unsure, say N.
19297d453eeeSMatt Fleming
1930506f1d07SSam Ravnborgconfig SECCOMP
19313c2362e6SHarvey Harrison	def_bool y
19323c2362e6SHarvey Harrison	prompt "Enable seccomp to safely compute untrusted bytecode"
19338f9ca475SIngo Molnar	---help---
1934506f1d07SSam Ravnborg	  This kernel feature is useful for number crunching applications
1935506f1d07SSam Ravnborg	  that may need to compute untrusted bytecode during their
1936506f1d07SSam Ravnborg	  execution. By using pipes or other transports made available to
1937506f1d07SSam Ravnborg	  the process as file descriptors supporting the read/write
1938506f1d07SSam Ravnborg	  syscalls, it's possible to isolate those applications in
1939506f1d07SSam Ravnborg	  their own address space using seccomp. Once seccomp is
19409c0bbee8SAlexey Dobriyan	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1941506f1d07SSam Ravnborg	  and the task is only allowed to execute a few safe syscalls
1942506f1d07SSam Ravnborg	  defined by each seccomp mode.
1943506f1d07SSam Ravnborg
1944506f1d07SSam Ravnborg	  If unsure, say Y. Only embedded should say N here.
1945506f1d07SSam Ravnborg
1946506f1d07SSam Ravnborgsource kernel/Kconfig.hz
1947506f1d07SSam Ravnborg
1948506f1d07SSam Ravnborgconfig KEXEC
1949506f1d07SSam Ravnborg	bool "kexec system call"
19502965faa5SDave Young	select KEXEC_CORE
19518f9ca475SIngo Molnar	---help---
1952506f1d07SSam Ravnborg	  kexec is a system call that implements the ability to shutdown your
1953506f1d07SSam Ravnborg	  current kernel, and to start another kernel.  It is like a reboot
1954506f1d07SSam Ravnborg	  but it is independent of the system firmware.   And like a reboot
1955506f1d07SSam Ravnborg	  you can start any kernel with it, not just Linux.
1956506f1d07SSam Ravnborg
1957506f1d07SSam Ravnborg	  The name comes from the similarity to the exec system call.
1958506f1d07SSam Ravnborg
1959506f1d07SSam Ravnborg	  It is an ongoing process to be certain the hardware in a machine
1960506f1d07SSam Ravnborg	  is properly shutdown, so do not be surprised if this code does not
1961bf220695SGeert Uytterhoeven	  initially work for you.  As of this writing the exact hardware
1962bf220695SGeert Uytterhoeven	  interface is strongly in flux, so no good recommendation can be
1963bf220695SGeert Uytterhoeven	  made.
1964506f1d07SSam Ravnborg
196574ca317cSVivek Goyalconfig KEXEC_FILE
196674ca317cSVivek Goyal	bool "kexec file based system call"
19672965faa5SDave Young	select KEXEC_CORE
196874ca317cSVivek Goyal	select BUILD_BIN2C
196974ca317cSVivek Goyal	depends on X86_64
197074ca317cSVivek Goyal	depends on CRYPTO=y
197174ca317cSVivek Goyal	depends on CRYPTO_SHA256=y
197274ca317cSVivek Goyal	---help---
197374ca317cSVivek Goyal	  This is new version of kexec system call. This system call is
197474ca317cSVivek Goyal	  file based and takes file descriptors as system call argument
197574ca317cSVivek Goyal	  for kernel and initramfs as opposed to list of segments as
197674ca317cSVivek Goyal	  accepted by previous system call.
197774ca317cSVivek Goyal
19788e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG
19798e7d8381SVivek Goyal	bool "Verify kernel signature during kexec_file_load() syscall"
198074ca317cSVivek Goyal	depends on KEXEC_FILE
19818e7d8381SVivek Goyal	---help---
19828e7d8381SVivek Goyal	  This option makes kernel signature verification mandatory for
1983d8eb8940SBorislav Petkov	  the kexec_file_load() syscall.
19848e7d8381SVivek Goyal
1985d8eb8940SBorislav Petkov	  In addition to that option, you need to enable signature
1986d8eb8940SBorislav Petkov	  verification for the corresponding kernel image type being
1987d8eb8940SBorislav Petkov	  loaded in order for this to work.
19888e7d8381SVivek Goyal
19898e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG
19908e7d8381SVivek Goyal	bool "Enable bzImage signature verification support"
19918e7d8381SVivek Goyal	depends on KEXEC_VERIFY_SIG
19928e7d8381SVivek Goyal	depends on SIGNED_PE_FILE_VERIFICATION
19938e7d8381SVivek Goyal	select SYSTEM_TRUSTED_KEYRING
19948e7d8381SVivek Goyal	---help---
19958e7d8381SVivek Goyal	  Enable bzImage signature verification support.
19968e7d8381SVivek Goyal
1997506f1d07SSam Ravnborgconfig CRASH_DUMP
199804b69447SPavel Machek	bool "kernel crash dumps"
1999506f1d07SSam Ravnborg	depends on X86_64 || (X86_32 && HIGHMEM)
20008f9ca475SIngo Molnar	---help---
2001506f1d07SSam Ravnborg	  Generate crash dump after being started by kexec.
2002506f1d07SSam Ravnborg	  This should be normally only set in special crash dump kernels
2003506f1d07SSam Ravnborg	  which are loaded in the main kernel with kexec-tools into
2004506f1d07SSam Ravnborg	  a specially reserved region and then later executed after
2005506f1d07SSam Ravnborg	  a crash by kdump/kexec. The crash dump kernel must be compiled
2006506f1d07SSam Ravnborg	  to a memory address not used by the main kernel or BIOS using
2007506f1d07SSam Ravnborg	  PHYSICAL_START, or it must be built as a relocatable image
2008506f1d07SSam Ravnborg	  (CONFIG_RELOCATABLE=y).
2009506f1d07SSam Ravnborg	  For more details see Documentation/kdump/kdump.txt
2010506f1d07SSam Ravnborg
20113ab83521SHuang Yingconfig KEXEC_JUMP
20126ea30386SKees Cook	bool "kexec jump"
2013fee7b0d8SHuang Ying	depends on KEXEC && HIBERNATION
20148f9ca475SIngo Molnar	---help---
201589081d17SHuang Ying	  Jump between original kernel and kexeced kernel and invoke
201689081d17SHuang Ying	  code in physical address mode via KEXEC
20173ab83521SHuang Ying
2018506f1d07SSam Ravnborgconfig PHYSICAL_START
20196a108a14SDavid Rientjes	hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
2020ceefccc9SH. Peter Anvin	default "0x1000000"
20218f9ca475SIngo Molnar	---help---
2022506f1d07SSam Ravnborg	  This gives the physical address where the kernel is loaded.
2023506f1d07SSam Ravnborg
2024506f1d07SSam Ravnborg	  If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2025506f1d07SSam Ravnborg	  bzImage will decompress itself to above physical address and
2026506f1d07SSam Ravnborg	  run from there. Otherwise, bzImage will run from the address where
2027506f1d07SSam Ravnborg	  it has been loaded by the boot loader and will ignore above physical
2028506f1d07SSam Ravnborg	  address.
2029506f1d07SSam Ravnborg
2030506f1d07SSam Ravnborg	  In normal kdump cases one does not have to set/change this option
2031506f1d07SSam Ravnborg	  as now bzImage can be compiled as a completely relocatable image
2032506f1d07SSam Ravnborg	  (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2033506f1d07SSam Ravnborg	  address. This option is mainly useful for the folks who don't want
2034506f1d07SSam Ravnborg	  to use a bzImage for capturing the crash dump and want to use a
2035506f1d07SSam Ravnborg	  vmlinux instead. vmlinux is not relocatable hence a kernel needs
2036506f1d07SSam Ravnborg	  to be specifically compiled to run from a specific memory area
2037506f1d07SSam Ravnborg	  (normally a reserved region) and this option comes handy.
2038506f1d07SSam Ravnborg
2039ceefccc9SH. Peter Anvin	  So if you are using bzImage for capturing the crash dump,
2040ceefccc9SH. Peter Anvin	  leave the value here unchanged to 0x1000000 and set
2041ceefccc9SH. Peter Anvin	  CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
2042ceefccc9SH. Peter Anvin	  for capturing the crash dump change this value to start of
2043ceefccc9SH. Peter Anvin	  the reserved region.  In other words, it can be set based on
2044ceefccc9SH. Peter Anvin	  the "X" value as specified in the "crashkernel=YM@XM"
2045ceefccc9SH. Peter Anvin	  command line boot parameter passed to the panic-ed
2046ceefccc9SH. Peter Anvin	  kernel. Please take a look at Documentation/kdump/kdump.txt
2047ceefccc9SH. Peter Anvin	  for more details about crash dumps.
2048506f1d07SSam Ravnborg
2049506f1d07SSam Ravnborg	  Usage of bzImage for capturing the crash dump is recommended as
2050506f1d07SSam Ravnborg	  one does not have to build two kernels. Same kernel can be used
2051506f1d07SSam Ravnborg	  as production kernel and capture kernel. Above option should have
2052506f1d07SSam Ravnborg	  gone away after relocatable bzImage support is introduced. But it
2053506f1d07SSam Ravnborg	  is present because there are users out there who continue to use
2054506f1d07SSam Ravnborg	  vmlinux for dump capture. This option should go away down the
2055506f1d07SSam Ravnborg	  line.
2056506f1d07SSam Ravnborg
2057506f1d07SSam Ravnborg	  Don't change this unless you know what you are doing.
2058506f1d07SSam Ravnborg
2059506f1d07SSam Ravnborgconfig RELOCATABLE
206026717808SH. Peter Anvin	bool "Build a relocatable kernel"
206126717808SH. Peter Anvin	default y
20628f9ca475SIngo Molnar	---help---
2063506f1d07SSam Ravnborg	  This builds a kernel image that retains relocation information
2064506f1d07SSam Ravnborg	  so it can be loaded someplace besides the default 1MB.
2065506f1d07SSam Ravnborg	  The relocations tend to make the kernel binary about 10% larger,
2066506f1d07SSam Ravnborg	  but are discarded at runtime.
2067506f1d07SSam Ravnborg
2068506f1d07SSam Ravnborg	  One use is for the kexec on panic case where the recovery kernel
2069506f1d07SSam Ravnborg	  must live at a different physical address than the primary
2070506f1d07SSam Ravnborg	  kernel.
2071506f1d07SSam Ravnborg
2072506f1d07SSam Ravnborg	  Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2073506f1d07SSam Ravnborg	  it has been loaded at and the compile time physical address
20748ab3820fSKees Cook	  (CONFIG_PHYSICAL_START) is used as the minimum location.
2075506f1d07SSam Ravnborg
20768ab3820fSKees Cookconfig RANDOMIZE_BASE
2077e8581e3dSBaoquan He	bool "Randomize the address of the kernel image (KASLR)"
20788ab3820fSKees Cook	depends on RELOCATABLE
20796807c846SIngo Molnar	default y
20808ab3820fSKees Cook	---help---
2081e8581e3dSBaoquan He	  In support of Kernel Address Space Layout Randomization (KASLR),
2082e8581e3dSBaoquan He	  this randomizes the physical address at which the kernel image
2083e8581e3dSBaoquan He	  is decompressed and the virtual address where the kernel
2084e8581e3dSBaoquan He	  image is mapped, as a security feature that deters exploit
2085e8581e3dSBaoquan He	  attempts relying on knowledge of the location of kernel
2086e8581e3dSBaoquan He	  code internals.
2087e8581e3dSBaoquan He
2088ed9f007eSKees Cook	  On 64-bit, the kernel physical and virtual addresses are
2089ed9f007eSKees Cook	  randomized separately. The physical address will be anywhere
2090ed9f007eSKees Cook	  between 16MB and the top of physical memory (up to 64TB). The
2091ed9f007eSKees Cook	  virtual address will be randomized from 16MB up to 1GB (9 bits
2092ed9f007eSKees Cook	  of entropy). Note that this also reduces the memory space
2093ed9f007eSKees Cook	  available to kernel modules from 1.5GB to 1GB.
2094ed9f007eSKees Cook
2095ed9f007eSKees Cook	  On 32-bit, the kernel physical and virtual addresses are
2096ed9f007eSKees Cook	  randomized together. They will be randomized from 16MB up to
2097ed9f007eSKees Cook	  512MB (8 bits of entropy).
20988ab3820fSKees Cook
2099a653f356SKees Cook	  Entropy is generated using the RDRAND instruction if it is
2100e8581e3dSBaoquan He	  supported. If RDTSC is supported, its value is mixed into
2101e8581e3dSBaoquan He	  the entropy pool as well. If neither RDRAND nor RDTSC are
2102ed9f007eSKees Cook	  supported, then entropy is read from the i8254 timer. The
2103ed9f007eSKees Cook	  usable entropy is limited by the kernel being built using
2104ed9f007eSKees Cook	  2GB addressing, and that PHYSICAL_ALIGN must be at a
2105ed9f007eSKees Cook	  minimum of 2MB. As a result, only 10 bits of entropy are
2106ed9f007eSKees Cook	  theoretically possible, but the implementations are further
2107ed9f007eSKees Cook	  limited due to memory layouts.
2108e8581e3dSBaoquan He
21096807c846SIngo Molnar	  If unsure, say Y.
2110da2b6fb9SKees Cook
21118ab3820fSKees Cook# Relocation on x86 needs some additional build support
2112845adf72SH. Peter Anvinconfig X86_NEED_RELOCS
2113845adf72SH. Peter Anvin	def_bool y
21148ab3820fSKees Cook	depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
2115845adf72SH. Peter Anvin
2116506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN
2117a0215061SKees Cook	hex "Alignment value to which kernel should be aligned"
21188ab3820fSKees Cook	default "0x200000"
2119a0215061SKees Cook	range 0x2000 0x1000000 if X86_32
2120a0215061SKees Cook	range 0x200000 0x1000000 if X86_64
21218f9ca475SIngo Molnar	---help---
2122506f1d07SSam Ravnborg	  This value puts the alignment restrictions on physical address
2123506f1d07SSam Ravnborg	  where kernel is loaded and run from. Kernel is compiled for an
2124506f1d07SSam Ravnborg	  address which meets above alignment restriction.
2125506f1d07SSam Ravnborg
2126506f1d07SSam Ravnborg	  If bootloader loads the kernel at a non-aligned address and
2127506f1d07SSam Ravnborg	  CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2128506f1d07SSam Ravnborg	  address aligned to above value and run from there.
2129506f1d07SSam Ravnborg
2130506f1d07SSam Ravnborg	  If bootloader loads the kernel at a non-aligned address and
2131506f1d07SSam Ravnborg	  CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2132506f1d07SSam Ravnborg	  load address and decompress itself to the address it has been
2133506f1d07SSam Ravnborg	  compiled for and run from there. The address for which kernel is
2134506f1d07SSam Ravnborg	  compiled already meets above alignment restrictions. Hence the
2135506f1d07SSam Ravnborg	  end result is that kernel runs from a physical address meeting
2136506f1d07SSam Ravnborg	  above alignment restrictions.
2137506f1d07SSam Ravnborg
2138a0215061SKees Cook	  On 32-bit this value must be a multiple of 0x2000. On 64-bit
2139a0215061SKees Cook	  this value must be a multiple of 0x200000.
2140a0215061SKees Cook
2141506f1d07SSam Ravnborg	  Don't change this unless you know what you are doing.
2142506f1d07SSam Ravnborg
21430483e1faSThomas Garnierconfig RANDOMIZE_MEMORY
21440483e1faSThomas Garnier	bool "Randomize the kernel memory sections"
21450483e1faSThomas Garnier	depends on X86_64
21460483e1faSThomas Garnier	depends on RANDOMIZE_BASE
21470483e1faSThomas Garnier	default RANDOMIZE_BASE
21480483e1faSThomas Garnier	---help---
21490483e1faSThomas Garnier	   Randomizes the base virtual address of kernel memory sections
21500483e1faSThomas Garnier	   (physical memory mapping, vmalloc & vmemmap). This security feature
21510483e1faSThomas Garnier	   makes exploits relying on predictable memory locations less reliable.
21520483e1faSThomas Garnier
21530483e1faSThomas Garnier	   The order of allocations remains unchanged. Entropy is generated in
21540483e1faSThomas Garnier	   the same way as RANDOMIZE_BASE. Current implementation in the optimal
21550483e1faSThomas Garnier	   configuration have in average 30,000 different possible virtual
21560483e1faSThomas Garnier	   addresses for each memory section.
21570483e1faSThomas Garnier
21586807c846SIngo Molnar	   If unsure, say Y.
21590483e1faSThomas Garnier
216090397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING
216190397a41SThomas Garnier	hex "Physical memory mapping padding" if EXPERT
216290397a41SThomas Garnier	depends on RANDOMIZE_MEMORY
216390397a41SThomas Garnier	default "0xa" if MEMORY_HOTPLUG
216490397a41SThomas Garnier	default "0x0"
216590397a41SThomas Garnier	range 0x1 0x40 if MEMORY_HOTPLUG
216690397a41SThomas Garnier	range 0x0 0x40
216790397a41SThomas Garnier	---help---
216890397a41SThomas Garnier	   Define the padding in terabytes added to the existing physical
216990397a41SThomas Garnier	   memory size during kernel memory randomization. It is useful
217090397a41SThomas Garnier	   for memory hotplug support but reduces the entropy available for
217190397a41SThomas Garnier	   address randomization.
217290397a41SThomas Garnier
217390397a41SThomas Garnier	   If unsure, leave at the default value.
217490397a41SThomas Garnier
2175506f1d07SSam Ravnborgconfig HOTPLUG_CPU
21767c13e6a3SDimitri Sivanich	bool "Support for hot-pluggable CPUs"
217740b31360SStephen Rothwell	depends on SMP
2178506f1d07SSam Ravnborg	---help---
21797c13e6a3SDimitri Sivanich	  Say Y here to allow turning CPUs off and on. CPUs can be
21807c13e6a3SDimitri Sivanich	  controlled through /sys/devices/system/cpu.
21817c13e6a3SDimitri Sivanich	  ( Note: power management support will enable this option
21827c13e6a3SDimitri Sivanich	    automatically on SMP systems. )
21837c13e6a3SDimitri Sivanich	  Say N if you want to disable CPU hotplug.
2184506f1d07SSam Ravnborg
218580aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0
218680aa1dffSFenghua Yu	bool "Set default setting of cpu0_hotpluggable"
218780aa1dffSFenghua Yu	default n
21882c922cd0SKees Cook	depends on HOTPLUG_CPU
218980aa1dffSFenghua Yu	---help---
219080aa1dffSFenghua Yu	  Set whether default state of cpu0_hotpluggable is on or off.
219180aa1dffSFenghua Yu
219280aa1dffSFenghua Yu	  Say Y here to enable CPU0 hotplug by default. If this switch
219380aa1dffSFenghua Yu	  is turned on, there is no need to give cpu0_hotplug kernel
219480aa1dffSFenghua Yu	  parameter and the CPU0 hotplug feature is enabled by default.
219580aa1dffSFenghua Yu
219680aa1dffSFenghua Yu	  Please note: there are two known CPU0 dependencies if you want
219780aa1dffSFenghua Yu	  to enable the CPU0 hotplug feature either by this switch or by
219880aa1dffSFenghua Yu	  cpu0_hotplug kernel parameter.
219980aa1dffSFenghua Yu
220080aa1dffSFenghua Yu	  First, resume from hibernate or suspend always starts from CPU0.
220180aa1dffSFenghua Yu	  So hibernate and suspend are prevented if CPU0 is offline.
220280aa1dffSFenghua Yu
220380aa1dffSFenghua Yu	  Second dependency is PIC interrupts always go to CPU0. CPU0 can not
220480aa1dffSFenghua Yu	  offline if any interrupt can not migrate out of CPU0. There may
220580aa1dffSFenghua Yu	  be other CPU0 dependencies.
220680aa1dffSFenghua Yu
220780aa1dffSFenghua Yu	  Please make sure the dependencies are under your control before
220880aa1dffSFenghua Yu	  you enable this feature.
220980aa1dffSFenghua Yu
221080aa1dffSFenghua Yu	  Say N if you don't want to enable CPU0 hotplug feature by default.
221180aa1dffSFenghua Yu	  You still can enable the CPU0 hotplug feature at boot by kernel
221280aa1dffSFenghua Yu	  parameter cpu0_hotplug.
221380aa1dffSFenghua Yu
2214a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0
2215a71c8bc5SFenghua Yu	def_bool n
2216a71c8bc5SFenghua Yu	prompt "Debug CPU0 hotplug"
22172c922cd0SKees Cook	depends on HOTPLUG_CPU
2218a71c8bc5SFenghua Yu	---help---
2219a71c8bc5SFenghua Yu	  Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2220a71c8bc5SFenghua Yu	  soon as possible and boots up userspace with CPU0 offlined. User
2221a71c8bc5SFenghua Yu	  can online CPU0 back after boot time.
2222a71c8bc5SFenghua Yu
2223a71c8bc5SFenghua Yu	  To debug CPU0 hotplug, you need to enable CPU0 offline/online
2224a71c8bc5SFenghua Yu	  feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2225a71c8bc5SFenghua Yu	  compilation or giving cpu0_hotplug kernel parameter at boot.
2226a71c8bc5SFenghua Yu
2227a71c8bc5SFenghua Yu	  If unsure, say N.
2228a71c8bc5SFenghua Yu
2229506f1d07SSam Ravnborgconfig COMPAT_VDSO
2230b0b49f26SAndy Lutomirski	def_bool n
2231b0b49f26SAndy Lutomirski	prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
2232953fee1dSIngo Molnar	depends on COMPAT_32
22338f9ca475SIngo Molnar	---help---
2234b0b49f26SAndy Lutomirski	  Certain buggy versions of glibc will crash if they are
2235b0b49f26SAndy Lutomirski	  presented with a 32-bit vDSO that is not mapped at the address
2236b0b49f26SAndy Lutomirski	  indicated in its segment table.
2237e84446deSRandy Dunlap
2238b0b49f26SAndy Lutomirski	  The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2239b0b49f26SAndy Lutomirski	  and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2240b0b49f26SAndy Lutomirski	  49ad572a70b8aeb91e57483a11dd1b77e31c4468.  Glibc 2.3.3 is
2241b0b49f26SAndy Lutomirski	  the only released version with the bug, but OpenSUSE 9
2242b0b49f26SAndy Lutomirski	  contains a buggy "glibc 2.3.2".
2243506f1d07SSam Ravnborg
2244b0b49f26SAndy Lutomirski	  The symptom of the bug is that everything crashes on startup, saying:
2245b0b49f26SAndy Lutomirski	  dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2246b0b49f26SAndy Lutomirski
2247b0b49f26SAndy Lutomirski	  Saying Y here changes the default value of the vdso32 boot
2248b0b49f26SAndy Lutomirski	  option from 1 to 0, which turns off the 32-bit vDSO entirely.
2249b0b49f26SAndy Lutomirski	  This works around the glibc bug but hurts performance.
2250b0b49f26SAndy Lutomirski
2251b0b49f26SAndy Lutomirski	  If unsure, say N: if you are compiling your own kernel, you
2252b0b49f26SAndy Lutomirski	  are unlikely to be using a buggy version of glibc.
2253506f1d07SSam Ravnborg
22543dc33bd3SKees Cookchoice
22553dc33bd3SKees Cook	prompt "vsyscall table for legacy applications"
22563dc33bd3SKees Cook	depends on X86_64
22573dc33bd3SKees Cook	default LEGACY_VSYSCALL_EMULATE
22583dc33bd3SKees Cook	help
22593dc33bd3SKees Cook	  Legacy user code that does not know how to find the vDSO expects
22603dc33bd3SKees Cook	  to be able to issue three syscalls by calling fixed addresses in
22613dc33bd3SKees Cook	  kernel space. Since this location is not randomized with ASLR,
22623dc33bd3SKees Cook	  it can be used to assist security vulnerability exploitation.
22633dc33bd3SKees Cook
22643dc33bd3SKees Cook	  This setting can be changed at boot time via the kernel command
22653dc33bd3SKees Cook	  line parameter vsyscall=[native|emulate|none].
22663dc33bd3SKees Cook
22673dc33bd3SKees Cook	  On a system with recent enough glibc (2.14 or newer) and no
22683dc33bd3SKees Cook	  static binaries, you can say None without a performance penalty
22693dc33bd3SKees Cook	  to improve security.
22703dc33bd3SKees Cook
22713dc33bd3SKees Cook	  If unsure, select "Emulate".
22723dc33bd3SKees Cook
22733dc33bd3SKees Cook	config LEGACY_VSYSCALL_NATIVE
22743dc33bd3SKees Cook		bool "Native"
22753dc33bd3SKees Cook		help
22763dc33bd3SKees Cook		  Actual executable code is located in the fixed vsyscall
22773dc33bd3SKees Cook		  address mapping, implementing time() efficiently. Since
22783dc33bd3SKees Cook		  this makes the mapping executable, it can be used during
22793dc33bd3SKees Cook		  security vulnerability exploitation (traditionally as
22803dc33bd3SKees Cook		  ROP gadgets). This configuration is not recommended.
22813dc33bd3SKees Cook
22823dc33bd3SKees Cook	config LEGACY_VSYSCALL_EMULATE
22833dc33bd3SKees Cook		bool "Emulate"
22843dc33bd3SKees Cook		help
22853dc33bd3SKees Cook		  The kernel traps and emulates calls into the fixed
22863dc33bd3SKees Cook		  vsyscall address mapping. This makes the mapping
22873dc33bd3SKees Cook		  non-executable, but it still contains known contents,
22883dc33bd3SKees Cook		  which could be used in certain rare security vulnerability
22893dc33bd3SKees Cook		  exploits. This configuration is recommended when userspace
22903dc33bd3SKees Cook		  still uses the vsyscall area.
22913dc33bd3SKees Cook
22923dc33bd3SKees Cook	config LEGACY_VSYSCALL_NONE
22933dc33bd3SKees Cook		bool "None"
22943dc33bd3SKees Cook		help
22953dc33bd3SKees Cook		  There will be no vsyscall mapping at all. This will
22963dc33bd3SKees Cook		  eliminate any risk of ASLR bypass due to the vsyscall
22973dc33bd3SKees Cook		  fixed address mapping. Attempts to use the vsyscalls
22983dc33bd3SKees Cook		  will be reported to dmesg, so that either old or
22993dc33bd3SKees Cook		  malicious userspace programs can be identified.
23003dc33bd3SKees Cook
23013dc33bd3SKees Cookendchoice
23023dc33bd3SKees Cook
2303516cbf37STim Birdconfig CMDLINE_BOOL
2304516cbf37STim Bird	bool "Built-in kernel command line"
23058f9ca475SIngo Molnar	---help---
2306516cbf37STim Bird	  Allow for specifying boot arguments to the kernel at
2307516cbf37STim Bird	  build time.  On some systems (e.g. embedded ones), it is
2308516cbf37STim Bird	  necessary or convenient to provide some or all of the
2309516cbf37STim Bird	  kernel boot arguments with the kernel itself (that is,
2310516cbf37STim Bird	  to not rely on the boot loader to provide them.)
2311516cbf37STim Bird
2312516cbf37STim Bird	  To compile command line arguments into the kernel,
2313516cbf37STim Bird	  set this option to 'Y', then fill in the
231469711ca1SSébastien Hinderer	  boot arguments in CONFIG_CMDLINE.
2315516cbf37STim Bird
2316516cbf37STim Bird	  Systems with fully functional boot loaders (i.e. non-embedded)
2317516cbf37STim Bird	  should leave this option set to 'N'.
2318516cbf37STim Bird
2319516cbf37STim Birdconfig CMDLINE
2320516cbf37STim Bird	string "Built-in kernel command string"
2321516cbf37STim Bird	depends on CMDLINE_BOOL
2322516cbf37STim Bird	default ""
23238f9ca475SIngo Molnar	---help---
2324516cbf37STim Bird	  Enter arguments here that should be compiled into the kernel
2325516cbf37STim Bird	  image and used at boot time.  If the boot loader provides a
2326516cbf37STim Bird	  command line at boot time, it is appended to this string to
2327516cbf37STim Bird	  form the full kernel command line, when the system boots.
2328516cbf37STim Bird
2329516cbf37STim Bird	  However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2330516cbf37STim Bird	  change this behavior.
2331516cbf37STim Bird
2332516cbf37STim Bird	  In most cases, the command line (whether built-in or provided
2333516cbf37STim Bird	  by the boot loader) should specify the device for the root
2334516cbf37STim Bird	  file system.
2335516cbf37STim Bird
2336516cbf37STim Birdconfig CMDLINE_OVERRIDE
2337516cbf37STim Bird	bool "Built-in command line overrides boot loader arguments"
2338516cbf37STim Bird	depends on CMDLINE_BOOL
23398f9ca475SIngo Molnar	---help---
2340516cbf37STim Bird	  Set this option to 'Y' to have the kernel ignore the boot loader
2341516cbf37STim Bird	  command line, and use ONLY the built-in command line.
2342516cbf37STim Bird
2343516cbf37STim Bird	  This is used to work around broken boot loaders.  This should
2344516cbf37STim Bird	  be set to 'N' under normal conditions.
2345516cbf37STim Bird
2346a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL
2347a5b9e5a2SAndy Lutomirski	bool "Enable the LDT (local descriptor table)" if EXPERT
2348a5b9e5a2SAndy Lutomirski	default y
2349a5b9e5a2SAndy Lutomirski	---help---
2350a5b9e5a2SAndy Lutomirski	  Linux can allow user programs to install a per-process x86
2351a5b9e5a2SAndy Lutomirski	  Local Descriptor Table (LDT) using the modify_ldt(2) system
2352a5b9e5a2SAndy Lutomirski	  call.  This is required to run 16-bit or segmented code such as
2353a5b9e5a2SAndy Lutomirski	  DOSEMU or some Wine programs.  It is also used by some very old
2354a5b9e5a2SAndy Lutomirski	  threading libraries.
2355a5b9e5a2SAndy Lutomirski
2356a5b9e5a2SAndy Lutomirski	  Enabling this feature adds a small amount of overhead to
2357a5b9e5a2SAndy Lutomirski	  context switches and increases the low-level kernel attack
2358a5b9e5a2SAndy Lutomirski	  surface.  Disabling it removes the modify_ldt(2) system call.
2359a5b9e5a2SAndy Lutomirski
2360a5b9e5a2SAndy Lutomirski	  Saying 'N' here may make sense for embedded or server kernels.
2361a5b9e5a2SAndy Lutomirski
2362b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig"
2363b700e7f0SSeth Jennings
2364506f1d07SSam Ravnborgendmenu
2365506f1d07SSam Ravnborg
23663072e413SMichal Hockoconfig ARCH_HAS_ADD_PAGES
23673072e413SMichal Hocko	def_bool y
23683072e413SMichal Hocko	depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
23693072e413SMichal Hocko
2370506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG
2371506f1d07SSam Ravnborg	def_bool y
2372506f1d07SSam Ravnborg	depends on X86_64 || (X86_32 && HIGHMEM)
2373506f1d07SSam Ravnborg
237435551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE
237535551053SGary Hade	def_bool y
237635551053SGary Hade	depends on MEMORY_HOTPLUG
237735551053SGary Hade
2378e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID
2379645a7919STejun Heo	def_bool y
2380e534c7c5SLee Schermerhorn	depends on NUMA
2381e534c7c5SLee Schermerhorn
23829491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK
23839491846fSKirill A. Shutemov	def_bool y
23849491846fSKirill A. Shutemov	depends on X86_64 || X86_PAE
23859491846fSKirill A. Shutemov
2386c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION
2387c177c81eSNaoya Horiguchi	def_bool y
2388c177c81eSNaoya Horiguchi	depends on X86_64 && HUGETLB_PAGE && MIGRATION
2389c177c81eSNaoya Horiguchi
23909c670ea3SNaoya Horiguchiconfig ARCH_ENABLE_THP_MIGRATION
23919c670ea3SNaoya Horiguchi	def_bool y
23929c670ea3SNaoya Horiguchi	depends on X86_64 && TRANSPARENT_HUGEPAGE
23939c670ea3SNaoya Horiguchi
2394da85f865SBjorn Helgaasmenu "Power management and ACPI options"
2395e279b6c1SSam Ravnborg
2396e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER
23973c2362e6SHarvey Harrison	def_bool y
2398e279b6c1SSam Ravnborg	depends on X86_64 && HIBERNATION
2399e279b6c1SSam Ravnborg
2400e279b6c1SSam Ravnborgsource "kernel/power/Kconfig"
2401e279b6c1SSam Ravnborg
2402e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig"
2403e279b6c1SSam Ravnborg
2404efafc8b2SFeng Tangsource "drivers/sfi/Kconfig"
2405efafc8b2SFeng Tang
2406a6b68076SAndi Kleenconfig X86_APM_BOOT
24076fc108a0SJan Beulich	def_bool y
2408282e5aabSPaul Bolle	depends on APM
2409a6b68076SAndi Kleen
2410e279b6c1SSam Ravnborgmenuconfig APM
2411e279b6c1SSam Ravnborg	tristate "APM (Advanced Power Management) BIOS support"
2412efefa6f6SIngo Molnar	depends on X86_32 && PM_SLEEP
2413e279b6c1SSam Ravnborg	---help---
2414e279b6c1SSam Ravnborg	  APM is a BIOS specification for saving power using several different
2415e279b6c1SSam Ravnborg	  techniques. This is mostly useful for battery powered laptops with
2416e279b6c1SSam Ravnborg	  APM compliant BIOSes. If you say Y here, the system time will be
2417e279b6c1SSam Ravnborg	  reset after a RESUME operation, the /proc/apm device will provide
2418e279b6c1SSam Ravnborg	  battery status information, and user-space programs will receive
2419e279b6c1SSam Ravnborg	  notification of APM "events" (e.g. battery status change).
2420e279b6c1SSam Ravnborg
2421e279b6c1SSam Ravnborg	  If you select "Y" here, you can disable actual use of the APM
2422e279b6c1SSam Ravnborg	  BIOS by passing the "apm=off" option to the kernel at boot time.
2423e279b6c1SSam Ravnborg
2424e279b6c1SSam Ravnborg	  Note that the APM support is almost completely disabled for
2425e279b6c1SSam Ravnborg	  machines with more than one CPU.
2426e279b6c1SSam Ravnborg
2427e279b6c1SSam Ravnborg	  In order to use APM, you will need supporting software. For location
24282dc98fd3SMichael Witten	  and more information, read <file:Documentation/power/apm-acpi.txt>
24292dc98fd3SMichael Witten	  and the Battery Powered Linux mini-HOWTO, available from
2430e279b6c1SSam Ravnborg	  <http://www.tldp.org/docs.html#howto>.
2431e279b6c1SSam Ravnborg
2432e279b6c1SSam Ravnborg	  This driver does not spin down disk drives (see the hdparm(8)
2433e279b6c1SSam Ravnborg	  manpage ("man 8 hdparm") for that), and it doesn't turn off
2434e279b6c1SSam Ravnborg	  VESA-compliant "green" monitors.
2435e279b6c1SSam Ravnborg
2436e279b6c1SSam Ravnborg	  This driver does not support the TI 4000M TravelMate and the ACER
2437e279b6c1SSam Ravnborg	  486/DX4/75 because they don't have compliant BIOSes. Many "green"
2438e279b6c1SSam Ravnborg	  desktop machines also don't have compliant BIOSes, and this driver
2439e279b6c1SSam Ravnborg	  may cause those machines to panic during the boot phase.
2440e279b6c1SSam Ravnborg
2441e279b6c1SSam Ravnborg	  Generally, if you don't have a battery in your machine, there isn't
2442e279b6c1SSam Ravnborg	  much point in using this driver and you should say N. If you get
2443e279b6c1SSam Ravnborg	  random kernel OOPSes or reboots that don't seem to be related to
2444e279b6c1SSam Ravnborg	  anything, try disabling/enabling this option (or disabling/enabling
2445e279b6c1SSam Ravnborg	  APM in your BIOS).
2446e279b6c1SSam Ravnborg
2447e279b6c1SSam Ravnborg	  Some other things you should try when experiencing seemingly random,
2448e279b6c1SSam Ravnborg	  "weird" problems:
2449e279b6c1SSam Ravnborg
2450e279b6c1SSam Ravnborg	  1) make sure that you have enough swap space and that it is
2451e279b6c1SSam Ravnborg	  enabled.
2452e279b6c1SSam Ravnborg	  2) pass the "no-hlt" option to the kernel
2453e279b6c1SSam Ravnborg	  3) switch on floating point emulation in the kernel and pass
2454e279b6c1SSam Ravnborg	  the "no387" option to the kernel
2455e279b6c1SSam Ravnborg	  4) pass the "floppy=nodma" option to the kernel
2456e279b6c1SSam Ravnborg	  5) pass the "mem=4M" option to the kernel (thereby disabling
2457e279b6c1SSam Ravnborg	  all but the first 4 MB of RAM)
2458e279b6c1SSam Ravnborg	  6) make sure that the CPU is not over clocked.
2459e279b6c1SSam Ravnborg	  7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2460e279b6c1SSam Ravnborg	  8) disable the cache from your BIOS settings
2461e279b6c1SSam Ravnborg	  9) install a fan for the video card or exchange video RAM
2462e279b6c1SSam Ravnborg	  10) install a better fan for the CPU
2463e279b6c1SSam Ravnborg	  11) exchange RAM chips
2464e279b6c1SSam Ravnborg	  12) exchange the motherboard.
2465e279b6c1SSam Ravnborg
2466e279b6c1SSam Ravnborg	  To compile this driver as a module, choose M here: the
2467e279b6c1SSam Ravnborg	  module will be called apm.
2468e279b6c1SSam Ravnborg
2469e279b6c1SSam Ravnborgif APM
2470e279b6c1SSam Ravnborg
2471e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND
2472e279b6c1SSam Ravnborg	bool "Ignore USER SUSPEND"
24738f9ca475SIngo Molnar	---help---
2474e279b6c1SSam Ravnborg	  This option will ignore USER SUSPEND requests. On machines with a
2475e279b6c1SSam Ravnborg	  compliant APM BIOS, you want to say N. However, on the NEC Versa M
2476e279b6c1SSam Ravnborg	  series notebooks, it is necessary to say Y because of a BIOS bug.
2477e279b6c1SSam Ravnborg
2478e279b6c1SSam Ravnborgconfig APM_DO_ENABLE
2479e279b6c1SSam Ravnborg	bool "Enable PM at boot time"
2480e279b6c1SSam Ravnborg	---help---
2481e279b6c1SSam Ravnborg	  Enable APM features at boot time. From page 36 of the APM BIOS
2482e279b6c1SSam Ravnborg	  specification: "When disabled, the APM BIOS does not automatically
2483e279b6c1SSam Ravnborg	  power manage devices, enter the Standby State, enter the Suspend
2484e279b6c1SSam Ravnborg	  State, or take power saving steps in response to CPU Idle calls."
2485e279b6c1SSam Ravnborg	  This driver will make CPU Idle calls when Linux is idle (unless this
2486e279b6c1SSam Ravnborg	  feature is turned off -- see "Do CPU IDLE calls", below). This
2487e279b6c1SSam Ravnborg	  should always save battery power, but more complicated APM features
2488e279b6c1SSam Ravnborg	  will be dependent on your BIOS implementation. You may need to turn
2489e279b6c1SSam Ravnborg	  this option off if your computer hangs at boot time when using APM
2490e279b6c1SSam Ravnborg	  support, or if it beeps continuously instead of suspending. Turn
2491e279b6c1SSam Ravnborg	  this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2492e279b6c1SSam Ravnborg	  T400CDT. This is off by default since most machines do fine without
2493e279b6c1SSam Ravnborg	  this feature.
2494e279b6c1SSam Ravnborg
2495e279b6c1SSam Ravnborgconfig APM_CPU_IDLE
2496dd8af076SLen Brown	depends on CPU_IDLE
2497e279b6c1SSam Ravnborg	bool "Make CPU Idle calls when idle"
24988f9ca475SIngo Molnar	---help---
2499e279b6c1SSam Ravnborg	  Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2500e279b6c1SSam Ravnborg	  On some machines, this can activate improved power savings, such as
2501e279b6c1SSam Ravnborg	  a slowed CPU clock rate, when the machine is idle. These idle calls
2502e279b6c1SSam Ravnborg	  are made after the idle loop has run for some length of time (e.g.,
2503e279b6c1SSam Ravnborg	  333 mS). On some machines, this will cause a hang at boot time or
2504e279b6c1SSam Ravnborg	  whenever the CPU becomes idle. (On machines with more than one CPU,
2505e279b6c1SSam Ravnborg	  this option does nothing.)
2506e279b6c1SSam Ravnborg
2507e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK
2508e279b6c1SSam Ravnborg	bool "Enable console blanking using APM"
25098f9ca475SIngo Molnar	---help---
2510e279b6c1SSam Ravnborg	  Enable console blanking using the APM. Some laptops can use this to
2511e279b6c1SSam Ravnborg	  turn off the LCD backlight when the screen blanker of the Linux
2512e279b6c1SSam Ravnborg	  virtual console blanks the screen. Note that this is only used by
2513e279b6c1SSam Ravnborg	  the virtual console screen blanker, and won't turn off the backlight
2514e279b6c1SSam Ravnborg	  when using the X Window system. This also doesn't have anything to
2515e279b6c1SSam Ravnborg	  do with your VESA-compliant power-saving monitor. Further, this
2516e279b6c1SSam Ravnborg	  option doesn't work for all laptops -- it might not turn off your
2517e279b6c1SSam Ravnborg	  backlight at all, or it might print a lot of errors to the console,
2518e279b6c1SSam Ravnborg	  especially if you are using gpm.
2519e279b6c1SSam Ravnborg
2520e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS
2521e279b6c1SSam Ravnborg	bool "Allow interrupts during APM BIOS calls"
25228f9ca475SIngo Molnar	---help---
2523e279b6c1SSam Ravnborg	  Normally we disable external interrupts while we are making calls to
2524e279b6c1SSam Ravnborg	  the APM BIOS as a measure to lessen the effects of a badly behaving
2525e279b6c1SSam Ravnborg	  BIOS implementation.  The BIOS should reenable interrupts if it
2526e279b6c1SSam Ravnborg	  needs to.  Unfortunately, some BIOSes do not -- especially those in
2527e279b6c1SSam Ravnborg	  many of the newer IBM Thinkpads.  If you experience hangs when you
2528e279b6c1SSam Ravnborg	  suspend, try setting this to Y.  Otherwise, say N.
2529e279b6c1SSam Ravnborg
2530e279b6c1SSam Ravnborgendif # APM
2531e279b6c1SSam Ravnborg
2532bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig"
2533e279b6c1SSam Ravnborg
2534e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig"
2535e279b6c1SSam Ravnborg
253627471fdbSAndy Henroidsource "drivers/idle/Kconfig"
253727471fdbSAndy Henroid
2538e279b6c1SSam Ravnborgendmenu
2539e279b6c1SSam Ravnborg
2540e279b6c1SSam Ravnborg
2541e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)"
2542e279b6c1SSam Ravnborg
2543e279b6c1SSam Ravnborgconfig PCI
25441ac97018SIngo Molnar	bool "PCI support"
25451c858087SAdrian Bunk	default y
25468f9ca475SIngo Molnar	---help---
2547e279b6c1SSam Ravnborg	  Find out whether you have a PCI motherboard. PCI is the name of a
2548e279b6c1SSam Ravnborg	  bus system, i.e. the way the CPU talks to the other stuff inside
2549e279b6c1SSam Ravnborg	  your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2550e279b6c1SSam Ravnborg	  VESA. If you have PCI, say Y, otherwise N.
2551e279b6c1SSam Ravnborg
2552e279b6c1SSam Ravnborgchoice
2553e279b6c1SSam Ravnborg	prompt "PCI access mode"
2554efefa6f6SIngo Molnar	depends on X86_32 && PCI
2555e279b6c1SSam Ravnborg	default PCI_GOANY
2556e279b6c1SSam Ravnborg	---help---
2557e279b6c1SSam Ravnborg	  On PCI systems, the BIOS can be used to detect the PCI devices and
2558e279b6c1SSam Ravnborg	  determine their configuration. However, some old PCI motherboards
2559e279b6c1SSam Ravnborg	  have BIOS bugs and may crash if this is done. Also, some embedded
2560e279b6c1SSam Ravnborg	  PCI-based systems don't have any BIOS at all. Linux can also try to
2561e279b6c1SSam Ravnborg	  detect the PCI hardware directly without using the BIOS.
2562e279b6c1SSam Ravnborg
2563e279b6c1SSam Ravnborg	  With this option, you can specify how Linux should detect the
2564e279b6c1SSam Ravnborg	  PCI devices. If you choose "BIOS", the BIOS will be used,
2565e279b6c1SSam Ravnborg	  if you choose "Direct", the BIOS won't be used, and if you
2566e279b6c1SSam Ravnborg	  choose "MMConfig", then PCI Express MMCONFIG will be used.
2567e279b6c1SSam Ravnborg	  If you choose "Any", the kernel will try MMCONFIG, then the
2568e279b6c1SSam Ravnborg	  direct access method and falls back to the BIOS if that doesn't
2569e279b6c1SSam Ravnborg	  work. If unsure, go with the default, which is "Any".
2570e279b6c1SSam Ravnborg
2571e279b6c1SSam Ravnborgconfig PCI_GOBIOS
2572e279b6c1SSam Ravnborg	bool "BIOS"
2573e279b6c1SSam Ravnborg
2574e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG
2575e279b6c1SSam Ravnborg	bool "MMConfig"
2576e279b6c1SSam Ravnborg
2577e279b6c1SSam Ravnborgconfig PCI_GODIRECT
2578e279b6c1SSam Ravnborg	bool "Direct"
2579e279b6c1SSam Ravnborg
25803ef0e1f8SAndres Salomonconfig PCI_GOOLPC
258176fb6570SDaniel Drake	bool "OLPC XO-1"
25823ef0e1f8SAndres Salomon	depends on OLPC
25833ef0e1f8SAndres Salomon
25842bdd1b03SAndres Salomonconfig PCI_GOANY
25852bdd1b03SAndres Salomon	bool "Any"
25862bdd1b03SAndres Salomon
2587e279b6c1SSam Ravnborgendchoice
2588e279b6c1SSam Ravnborg
2589e279b6c1SSam Ravnborgconfig PCI_BIOS
25903c2362e6SHarvey Harrison	def_bool y
2591efefa6f6SIngo Molnar	depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2592e279b6c1SSam Ravnborg
2593e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2594e279b6c1SSam Ravnborgconfig PCI_DIRECT
25953c2362e6SHarvey Harrison	def_bool y
25960aba496fSShaohua Li	depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2597e279b6c1SSam Ravnborg
2598e279b6c1SSam Ravnborgconfig PCI_MMCONFIG
25993c2362e6SHarvey Harrison	def_bool y
26005f0db7a2SFeng Tang	depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2601e279b6c1SSam Ravnborg
26023ef0e1f8SAndres Salomonconfig PCI_OLPC
26032bdd1b03SAndres Salomon	def_bool y
26042bdd1b03SAndres Salomon	depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
26053ef0e1f8SAndres Salomon
2606b5401a96SAlex Nixonconfig PCI_XEN
2607b5401a96SAlex Nixon	def_bool y
2608b5401a96SAlex Nixon	depends on PCI && XEN
2609b5401a96SAlex Nixon	select SWIOTLB_XEN
2610b5401a96SAlex Nixon
2611e279b6c1SSam Ravnborgconfig PCI_DOMAINS
26123c2362e6SHarvey Harrison	def_bool y
2613e279b6c1SSam Ravnborg	depends on PCI
2614e279b6c1SSam Ravnborg
2615e279b6c1SSam Ravnborgconfig PCI_MMCONFIG
2616e279b6c1SSam Ravnborg	bool "Support mmconfig PCI config space access"
2617e279b6c1SSam Ravnborg	depends on X86_64 && PCI && ACPI
2618e279b6c1SSam Ravnborg
26193f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK
26206a108a14SDavid Rientjes	bool "Read CNB20LE Host Bridge Windows" if EXPERT
26216ea30386SKees Cook	depends on PCI
26223f6ea84aSIra W. Snyder	help
26233f6ea84aSIra W. Snyder	  Read the PCI windows out of the CNB20LE host bridge. This allows
26243f6ea84aSIra W. Snyder	  PCI hotplug to work on systems with the CNB20LE chipset which do
26253f6ea84aSIra W. Snyder	  not have ACPI.
26263f6ea84aSIra W. Snyder
262764a5fed6SBjorn Helgaas	  There's no public spec for this chipset, and this functionality
262864a5fed6SBjorn Helgaas	  is known to be incomplete.
262964a5fed6SBjorn Helgaas
263064a5fed6SBjorn Helgaas	  You should say N unless you know you need this.
263164a5fed6SBjorn Helgaas
2632e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig"
2633e279b6c1SSam Ravnborg
26343a495511SWilliam Breathitt Grayconfig ISA_BUS
26353a495511SWilliam Breathitt Gray	bool "ISA-style bus support on modern systems" if EXPERT
26363a495511SWilliam Breathitt Gray	select ISA_BUS_API
26373a495511SWilliam Breathitt Gray	help
26383a495511SWilliam Breathitt Gray	  Enables ISA-style drivers on modern systems. This is necessary to
26393a495511SWilliam Breathitt Gray	  support PC/104 devices on X86_64 platforms.
26403a495511SWilliam Breathitt Gray
26413a495511SWilliam Breathitt Gray	  If unsure, say N.
26423a495511SWilliam Breathitt Gray
26431c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA.
2644e279b6c1SSam Ravnborgconfig ISA_DMA_API
26451c00f016SDavid Rientjes	bool "ISA-style DMA support" if (X86_64 && EXPERT)
26461c00f016SDavid Rientjes	default y
26471c00f016SDavid Rientjes	help
26481c00f016SDavid Rientjes	  Enables ISA-style DMA support for devices requiring such controllers.
26491c00f016SDavid Rientjes	  If unsure, say Y.
2650e279b6c1SSam Ravnborg
265151e68d05SLinus Torvaldsif X86_32
265251e68d05SLinus Torvalds
2653e279b6c1SSam Ravnborgconfig ISA
2654e279b6c1SSam Ravnborg	bool "ISA support"
26558f9ca475SIngo Molnar	---help---
2656e279b6c1SSam Ravnborg	  Find out whether you have ISA slots on your motherboard.  ISA is the
2657e279b6c1SSam Ravnborg	  name of a bus system, i.e. the way the CPU talks to the other stuff
2658e279b6c1SSam Ravnborg	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
2659e279b6c1SSam Ravnborg	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2660e279b6c1SSam Ravnborg	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
2661e279b6c1SSam Ravnborg
2662e279b6c1SSam Ravnborgconfig EISA
2663e279b6c1SSam Ravnborg	bool "EISA support"
2664e279b6c1SSam Ravnborg	depends on ISA
2665e279b6c1SSam Ravnborg	---help---
2666e279b6c1SSam Ravnborg	  The Extended Industry Standard Architecture (EISA) bus was
2667e279b6c1SSam Ravnborg	  developed as an open alternative to the IBM MicroChannel bus.
2668e279b6c1SSam Ravnborg
2669e279b6c1SSam Ravnborg	  The EISA bus provided some of the features of the IBM MicroChannel
2670e279b6c1SSam Ravnborg	  bus while maintaining backward compatibility with cards made for
2671e279b6c1SSam Ravnborg	  the older ISA bus.  The EISA bus saw limited use between 1988 and
2672e279b6c1SSam Ravnborg	  1995 when it was made obsolete by the PCI bus.
2673e279b6c1SSam Ravnborg
2674e279b6c1SSam Ravnborg	  Say Y here if you are building a kernel for an EISA-based machine.
2675e279b6c1SSam Ravnborg
2676e279b6c1SSam Ravnborg	  Otherwise, say N.
2677e279b6c1SSam Ravnborg
2678e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig"
2679e279b6c1SSam Ravnborg
2680e279b6c1SSam Ravnborgconfig SCx200
2681e279b6c1SSam Ravnborg	tristate "NatSemi SCx200 support"
26828f9ca475SIngo Molnar	---help---
2683e279b6c1SSam Ravnborg	  This provides basic support for National Semiconductor's
2684e279b6c1SSam Ravnborg	  (now AMD's) Geode processors.  The driver probes for the
2685e279b6c1SSam Ravnborg	  PCI-IDs of several on-chip devices, so its a good dependency
2686e279b6c1SSam Ravnborg	  for other scx200_* drivers.
2687e279b6c1SSam Ravnborg
2688e279b6c1SSam Ravnborg	  If compiled as a module, the driver is named scx200.
2689e279b6c1SSam Ravnborg
2690e279b6c1SSam Ravnborgconfig SCx200HR_TIMER
2691e279b6c1SSam Ravnborg	tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2692592913ecSJohn Stultz	depends on SCx200
2693e279b6c1SSam Ravnborg	default y
26948f9ca475SIngo Molnar	---help---
2695e279b6c1SSam Ravnborg	  This driver provides a clocksource built upon the on-chip
2696e279b6c1SSam Ravnborg	  27MHz high-resolution timer.  Its also a workaround for
2697e279b6c1SSam Ravnborg	  NSC Geode SC-1100's buggy TSC, which loses time when the
2698e279b6c1SSam Ravnborg	  processor goes idle (as is done by the scheduler).  The
2699e279b6c1SSam Ravnborg	  other workaround is idle=poll boot option.
2700e279b6c1SSam Ravnborg
27013ef0e1f8SAndres Salomonconfig OLPC
27023ef0e1f8SAndres Salomon	bool "One Laptop Per Child support"
270354008979SThomas Gleixner	depends on !X86_PAE
27043c554946SAndres Salomon	select GPIOLIB
2705dc3119e7SThomas Gleixner	select OF
270645bb1674SDaniel Drake	select OF_PROMTREE
2707b4e51854SGrant Likely	select IRQ_DOMAIN
27088f9ca475SIngo Molnar	---help---
27093ef0e1f8SAndres Salomon	  Add support for detecting the unique features of the OLPC
27103ef0e1f8SAndres Salomon	  XO hardware.
27113ef0e1f8SAndres Salomon
2712a3128588SDaniel Drakeconfig OLPC_XO1_PM
2713a3128588SDaniel Drake	bool "OLPC XO-1 Power Management"
271497c4cb71SDaniel Drake	depends on OLPC && MFD_CS5535 && PM_SLEEP
2715a3128588SDaniel Drake	select MFD_CORE
2716bf1ebf00SDaniel Drake	---help---
271797c4cb71SDaniel Drake	  Add support for poweroff and suspend of the OLPC XO-1 laptop.
2718bf1ebf00SDaniel Drake
2719cfee9597SDaniel Drakeconfig OLPC_XO1_RTC
2720cfee9597SDaniel Drake	bool "OLPC XO-1 Real Time Clock"
2721cfee9597SDaniel Drake	depends on OLPC_XO1_PM && RTC_DRV_CMOS
2722cfee9597SDaniel Drake	---help---
2723cfee9597SDaniel Drake	  Add support for the XO-1 real time clock, which can be used as a
2724cfee9597SDaniel Drake	  programmable wakeup source.
2725cfee9597SDaniel Drake
27267feda8e9SDaniel Drakeconfig OLPC_XO1_SCI
27277feda8e9SDaniel Drake	bool "OLPC XO-1 SCI extras"
2728d8d01a63SDaniel Drake	depends on OLPC && OLPC_XO1_PM
2729ed8e47feSRandy Dunlap	depends on INPUT=y
2730d8d01a63SDaniel Drake	select POWER_SUPPLY
27317feda8e9SDaniel Drake	select GPIO_CS5535
27327feda8e9SDaniel Drake	select MFD_CORE
27337feda8e9SDaniel Drake	---help---
27347feda8e9SDaniel Drake	  Add support for SCI-based features of the OLPC XO-1 laptop:
27357bc74b3dSDaniel Drake	   - EC-driven system wakeups
27367feda8e9SDaniel Drake	   - Power button
27377bc74b3dSDaniel Drake	   - Ebook switch
27382cf2baeaSDaniel Drake	   - Lid switch
2739e1040ac6SDaniel Drake	   - AC adapter status updates
2740e1040ac6SDaniel Drake	   - Battery status updates
27417feda8e9SDaniel Drake
2742a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI
2743a0f30f59SDaniel Drake	bool "OLPC XO-1.5 SCI extras"
2744d8d01a63SDaniel Drake	depends on OLPC && ACPI
2745d8d01a63SDaniel Drake	select POWER_SUPPLY
2746a0f30f59SDaniel Drake	---help---
2747a0f30f59SDaniel Drake	  Add support for SCI-based features of the OLPC XO-1.5 laptop:
2748a0f30f59SDaniel Drake	   - EC-driven system wakeups
2749a0f30f59SDaniel Drake	   - AC adapter status updates
2750a0f30f59SDaniel Drake	   - Battery status updates
2751e279b6c1SSam Ravnborg
2752d4f3e350SEd Wildgooseconfig ALIX
2753d4f3e350SEd Wildgoose	bool "PCEngines ALIX System Support (LED setup)"
2754d4f3e350SEd Wildgoose	select GPIOLIB
2755d4f3e350SEd Wildgoose	---help---
2756d4f3e350SEd Wildgoose	  This option enables system support for the PCEngines ALIX.
2757d4f3e350SEd Wildgoose	  At present this just sets up LEDs for GPIO control on
2758d4f3e350SEd Wildgoose	  ALIX2/3/6 boards.  However, other system specific setup should
2759d4f3e350SEd Wildgoose	  get added here.
2760d4f3e350SEd Wildgoose
2761d4f3e350SEd Wildgoose	  Note: You must still enable the drivers for GPIO and LED support
2762d4f3e350SEd Wildgoose	  (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2763d4f3e350SEd Wildgoose
2764d4f3e350SEd Wildgoose	  Note: You have to set alix.force=1 for boards with Award BIOS.
2765d4f3e350SEd Wildgoose
2766da4e3302SPhilip Prindevilleconfig NET5501
2767da4e3302SPhilip Prindeville	bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2768da4e3302SPhilip Prindeville	select GPIOLIB
2769da4e3302SPhilip Prindeville	---help---
2770da4e3302SPhilip Prindeville	  This option enables system support for the Soekris Engineering net5501.
2771da4e3302SPhilip Prindeville
27723197059aSPhilip A. Prindevilleconfig GEOS
27733197059aSPhilip A. Prindeville	bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
27743197059aSPhilip A. Prindeville	select GPIOLIB
27753197059aSPhilip A. Prindeville	depends on DMI
27763197059aSPhilip A. Prindeville	---help---
27773197059aSPhilip A. Prindeville	  This option enables system support for the Traverse Technologies GEOS.
27783197059aSPhilip A. Prindeville
27797d029125SVivien Didelotconfig TS5500
27807d029125SVivien Didelot	bool "Technologic Systems TS-5500 platform support"
27817d029125SVivien Didelot	depends on MELAN
27827d029125SVivien Didelot	select CHECK_SIGNATURE
27837d029125SVivien Didelot	select NEW_LEDS
27847d029125SVivien Didelot	select LEDS_CLASS
27857d029125SVivien Didelot	---help---
27867d029125SVivien Didelot	  This option enables system support for the Technologic Systems TS-5500.
27877d029125SVivien Didelot
2788e279b6c1SSam Ravnborgendif # X86_32
2789e279b6c1SSam Ravnborg
279023ac4ae8SAndreas Herrmannconfig AMD_NB
2791e279b6c1SSam Ravnborg	def_bool y
27920e152cd7SBorislav Petkov	depends on CPU_SUP_AMD && PCI
2793e279b6c1SSam Ravnborg
2794e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig"
2795e279b6c1SSam Ravnborg
2796388b78adSAlexandre Bounineconfig RAPIDIO
2797fdf90abcSAlexandre Bounine	tristate "RapidIO support"
2798388b78adSAlexandre Bounine	depends on PCI
2799388b78adSAlexandre Bounine	default n
2800388b78adSAlexandre Bounine	help
2801fdf90abcSAlexandre Bounine	  If enabled this option will include drivers and the core
2802388b78adSAlexandre Bounine	  infrastructure code to support RapidIO interconnect devices.
2803388b78adSAlexandre Bounine
2804388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig"
2805388b78adSAlexandre Bounine
2806e3263ab3SDavid Herrmannconfig X86_SYSFB
2807e3263ab3SDavid Herrmann	bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2808e3263ab3SDavid Herrmann	help
2809e3263ab3SDavid Herrmann	  Firmwares often provide initial graphics framebuffers so the BIOS,
2810e3263ab3SDavid Herrmann	  bootloader or kernel can show basic video-output during boot for
2811e3263ab3SDavid Herrmann	  user-guidance and debugging. Historically, x86 used the VESA BIOS
2812e3263ab3SDavid Herrmann	  Extensions and EFI-framebuffers for this, which are mostly limited
2813e3263ab3SDavid Herrmann	  to x86.
2814e3263ab3SDavid Herrmann	  This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2815e3263ab3SDavid Herrmann	  framebuffers so the new generic system-framebuffer drivers can be
2816e3263ab3SDavid Herrmann	  used on x86. If the framebuffer is not compatible with the generic
2817e3263ab3SDavid Herrmann	  modes, it is adverticed as fallback platform framebuffer so legacy
2818e3263ab3SDavid Herrmann	  drivers like efifb, vesafb and uvesafb can pick it up.
2819e3263ab3SDavid Herrmann	  If this option is not selected, all system framebuffers are always
2820e3263ab3SDavid Herrmann	  marked as fallback platform framebuffers as usual.
2821e3263ab3SDavid Herrmann
2822e3263ab3SDavid Herrmann	  Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2823e3263ab3SDavid Herrmann	  not be able to pick up generic system framebuffers if this option
2824e3263ab3SDavid Herrmann	  is selected. You are highly encouraged to enable simplefb as
2825e3263ab3SDavid Herrmann	  replacement if you select this option. simplefb can correctly deal
2826e3263ab3SDavid Herrmann	  with generic system framebuffers. But you should still keep vesafb
2827e3263ab3SDavid Herrmann	  and others enabled as fallback if a system framebuffer is
2828e3263ab3SDavid Herrmann	  incompatible with simplefb.
2829e3263ab3SDavid Herrmann
2830e3263ab3SDavid Herrmann	  If unsure, say Y.
2831e3263ab3SDavid Herrmann
2832e279b6c1SSam Ravnborgendmenu
2833e279b6c1SSam Ravnborg
2834e279b6c1SSam Ravnborg
2835e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations"
2836e279b6c1SSam Ravnborg
2837e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt"
2838e279b6c1SSam Ravnborg
2839e279b6c1SSam Ravnborgconfig IA32_EMULATION
2840e279b6c1SSam Ravnborg	bool "IA32 Emulation"
2841e279b6c1SSam Ravnborg	depends on X86_64
284239f88911SIngo Molnar	select ARCH_WANT_OLD_COMPAT_IPC
2843d1603990SRandy Dunlap	select BINFMT_ELF
2844a97f52e6SRoland McGrath	select COMPAT_BINFMT_ELF
284539f88911SIngo Molnar	select COMPAT_OLD_SIGACTION
28468f9ca475SIngo Molnar	---help---
28475fd92e65SH. J. Lu	  Include code to run legacy 32-bit programs under a
28485fd92e65SH. J. Lu	  64-bit kernel. You should likely turn this on, unless you're
28495fd92e65SH. J. Lu	  100% sure that you don't have any 32-bit programs left.
2850e279b6c1SSam Ravnborg
2851e279b6c1SSam Ravnborgconfig IA32_AOUT
2852e279b6c1SSam Ravnborg	tristate "IA32 a.out support"
28536b213e1bSDavid Woodhouse	depends on IA32_EMULATION
28548f9ca475SIngo Molnar	---help---
2855e279b6c1SSam Ravnborg	  Support old a.out binaries in the 32bit emulation.
2856e279b6c1SSam Ravnborg
28570bf62763SH. Peter Anvinconfig X86_X32
28586ea30386SKees Cook	bool "x32 ABI for 64-bit mode"
28599b54050bSBrian Gerst	depends on X86_64
28605fd92e65SH. J. Lu	---help---
28615fd92e65SH. J. Lu	  Include code to run binaries for the x32 native 32-bit ABI
28625fd92e65SH. J. Lu	  for 64-bit processors.  An x32 process gets access to the
28635fd92e65SH. J. Lu	  full 64-bit register file and wide data path while leaving
28645fd92e65SH. J. Lu	  pointers at 32 bits for smaller memory footprint.
28655fd92e65SH. J. Lu
28665fd92e65SH. J. Lu	  You will need a recent binutils (2.22 or later) with
28675fd92e65SH. J. Lu	  elf32_x86_64 support enabled to compile a kernel with this
28685fd92e65SH. J. Lu	  option set.
28695fd92e65SH. J. Lu
2870953fee1dSIngo Molnarconfig COMPAT_32
2871953fee1dSIngo Molnar	def_bool y
2872953fee1dSIngo Molnar	depends on IA32_EMULATION || X86_32
2873953fee1dSIngo Molnar	select HAVE_UID16
2874953fee1dSIngo Molnar	select OLD_SIGSUSPEND3
2875953fee1dSIngo Molnar
2876e279b6c1SSam Ravnborgconfig COMPAT
28773c2362e6SHarvey Harrison	def_bool y
28780bf62763SH. Peter Anvin	depends on IA32_EMULATION || X86_X32
2879e279b6c1SSam Ravnborg
28803120e25eSJan Beulichif COMPAT
2881e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT
28823120e25eSJan Beulich	def_bool y
2883e279b6c1SSam Ravnborg
2884e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT
28853c2362e6SHarvey Harrison	def_bool y
28863120e25eSJan Beulich	depends on SYSVIPC
28873120e25eSJan Beulichendif
2888ee009e4aSDavid Howells
2889e279b6c1SSam Ravnborgendmenu
2890e279b6c1SSam Ravnborg
2891e279b6c1SSam Ravnborg
2892e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP
2893e5beae16SKeith Packard	def_bool y
2894e5beae16SKeith Packard	depends on X86_32
2895e5beae16SKeith Packard
28964692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS
28974692d77fSAlessandro Rubini	bool
289883125a3aSAlessandro Rubini	depends on X86_64 || STA2X11
28994692d77fSAlessandro Rubini
2900f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP
2901f7219a53SAlessandro Rubini	bool
290283125a3aSAlessandro Rubini	depends on STA2X11
2903f7219a53SAlessandro Rubini
2904e585513bSKirill A. Shutemovconfig HAVE_GENERIC_GUP
2905e585513bSKirill A. Shutemov	def_bool y
2906e585513bSKirill A. Shutemov
2907e279b6c1SSam Ravnborgsource "net/Kconfig"
2908e279b6c1SSam Ravnborg
2909e279b6c1SSam Ravnborgsource "drivers/Kconfig"
2910e279b6c1SSam Ravnborg
2911e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig"
2912e279b6c1SSam Ravnborg
2913e279b6c1SSam Ravnborgsource "fs/Kconfig"
2914e279b6c1SSam Ravnborg
2915e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug"
2916e279b6c1SSam Ravnborg
2917e279b6c1SSam Ravnborgsource "security/Kconfig"
2918e279b6c1SSam Ravnborg
2919e279b6c1SSam Ravnborgsource "crypto/Kconfig"
2920e279b6c1SSam Ravnborg
2921edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig"
2922edf88417SAvi Kivity
2923e279b6c1SSam Ravnborgsource "lib/Kconfig"
2924