xref: /linux/arch/x86/Kconfig (revision 07431506e8d752ff21c3d5fba0927fe8be4ed18f)
1b2441318SGreg Kroah-Hartman# SPDX-License-Identifier: GPL-2.0
2daa93fabSSam Ravnborg# Select 32 or 64 bit
3daa93fabSSam Ravnborgconfig 64BIT
4104daea1SMasahiro Yamada	bool "64-bit kernel" if "$(ARCH)" = "x86"
5104daea1SMasahiro Yamada	default "$(ARCH)" != "i386"
6a7f7f624SMasahiro Yamada	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
17157e118bSThomas Gleixner	select GENERIC_VDSO_32
18117ed454SThomas Gleixner	select HAVE_DEBUG_STACKOVERFLOW
19157e118bSThomas Gleixner	select KMAP_LOCAL
20341c787eSIngo Molnar	select MODULES_USE_ELF_REL
21341c787eSIngo Molnar	select OLD_SIGACTION
222ca408d9SBrian Gerst	select ARCH_SPLIT_ARG64
23daa93fabSSam Ravnborg
24daa93fabSSam Ravnborgconfig X86_64
253120e25eSJan Beulich	def_bool y
263120e25eSJan Beulich	depends on 64BIT
27d94e0685SIngo Molnar	# Options that are inherently 64-bit kernel only:
284eb0716eSAlexandre Ghiti	select ARCH_HAS_GIGANTIC_PAGE
29c12d3362SArd Biesheuvel	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
30d94e0685SIngo Molnar	select ARCH_USE_CMPXCHG_LOCKREF
31d94e0685SIngo Molnar	select HAVE_ARCH_SOFT_DIRTY
32d94e0685SIngo Molnar	select MODULES_USE_ELF_RELA
33f616ab59SChristoph Hellwig	select NEED_DMA_MAP_STATE
3409230cbcSChristoph Hellwig	select SWIOTLB
357facdc42SAl Viro	select ARCH_HAS_ELFCORE_COMPAT
3663703f37SKefeng Wang	select ZONE_DMA32
371032c0baSSam Ravnborg
38518049d9SSteven Rostedt (VMware)config FORCE_DYNAMIC_FTRACE
39518049d9SSteven Rostedt (VMware)	def_bool y
40518049d9SSteven Rostedt (VMware)	depends on X86_32
41518049d9SSteven Rostedt (VMware)	depends on FUNCTION_TRACER
42518049d9SSteven Rostedt (VMware)	select DYNAMIC_FTRACE
43518049d9SSteven Rostedt (VMware)	help
44518049d9SSteven Rostedt (VMware)	 We keep the static function tracing (!DYNAMIC_FTRACE) around
45518049d9SSteven Rostedt (VMware)	 in order to test the non static function tracing in the
46518049d9SSteven Rostedt (VMware)	 generic code, as other architectures still use it. But we
47518049d9SSteven Rostedt (VMware)	 only need to keep it around for x86_64. No need to keep it
48518049d9SSteven Rostedt (VMware)	 for x86_32. For x86_32, force DYNAMIC_FTRACE.
49d94e0685SIngo Molnar#
50d94e0685SIngo Molnar# Arch settings
51d94e0685SIngo Molnar#
52d94e0685SIngo Molnar# ( Note that options that are marked 'if X86_64' could in principle be
53d94e0685SIngo Molnar#   ported to 32-bit as well. )
54d94e0685SIngo Molnar#
558d5fffb9SSam Ravnborgconfig X86
563c2362e6SHarvey Harrison	def_bool y
57c763ea26SIngo Molnar	#
58c763ea26SIngo Molnar	# Note: keep this list sorted alphabetically
59c763ea26SIngo Molnar	#
606471b825SIngo Molnar	select ACPI_LEGACY_TABLES_LOOKUP	if ACPI
616e0a0ea1SGraeme Gregory	select ACPI_SYSTEM_POWER_STATES_SUPPORT	if ACPI
62942fa985SYury Norov	select ARCH_32BIT_OFF_T			if X86_32
632a21ad57SThomas Gleixner	select ARCH_CLOCKSOURCE_INIT
641f6d3a8fSMasami Hiramatsu	select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
651e866974SAnshuman Khandual	select ARCH_ENABLE_HUGEPAGE_MIGRATION if X86_64 && HUGETLB_PAGE && MIGRATION
665c11f00bSDavid Hildenbrand	select ARCH_ENABLE_MEMORY_HOTPLUG if X86_64
6791024b3cSAnshuman Khandual	select ARCH_ENABLE_MEMORY_HOTREMOVE if MEMORY_HOTPLUG
68cebc774fSAnshuman Khandual	select ARCH_ENABLE_SPLIT_PMD_PTLOCK if (PGTABLE_LEVELS > 2) && (X86_64 || X86_PAE)
691e866974SAnshuman Khandual	select ARCH_ENABLE_THP_MIGRATION if X86_64 && TRANSPARENT_HUGEPAGE
7091dda51aSAleksey Makarov	select ARCH_HAS_ACPI_TABLE_UPGRADE	if ACPI
71c2280be8SAnshuman Khandual	select ARCH_HAS_CACHE_LINE_SIZE
72fa5b6ec9SLaura Abbott	select ARCH_HAS_DEBUG_VIRTUAL
73399145f9SAnshuman Khandual	select ARCH_HAS_DEBUG_VM_PGTABLE	if !X86_PAE
7421266be9SDan Williams	select ARCH_HAS_DEVMEM_IS_ALLOWED
75b1a57bbfSDouglas Anderson	select ARCH_HAS_EARLY_DEBUG		if KGDB
766471b825SIngo Molnar	select ARCH_HAS_ELF_RANDOMIZE
7772d93104SLinus Torvalds	select ARCH_HAS_FAST_MULTIPLIER
78316d097cSDave Hansen	select ARCH_HAS_FILTER_PGPROT
796974f0c4SDaniel Micay	select ARCH_HAS_FORTIFY_SOURCE
80957e3facSRiku Voipio	select ARCH_HAS_GCOV_PROFILE_ALL
81bece04b5SMarco Elver	select ARCH_HAS_KCOV			if X86_64
820c9c1d56SThiago Jung Bauermann	select ARCH_HAS_MEM_ENCRYPT
8310bcc80eSMathieu Desnoyers	select ARCH_HAS_MEMBARRIER_SYNC_CORE
840ebeea8cSDaniel Borkmann	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
85c763ea26SIngo Molnar	select ARCH_HAS_PMEM_API		if X86_64
8617596731SRobin Murphy	select ARCH_HAS_PTE_DEVMAP		if X86_64
873010a5eaSLaurent Dufour	select ARCH_HAS_PTE_SPECIAL
880aed55afSDan Williams	select ARCH_HAS_UACCESS_FLUSHCACHE	if X86_64
89ec6347bbSDan Williams	select ARCH_HAS_COPY_MC			if X86_64
90d2852a22SDaniel Borkmann	select ARCH_HAS_SET_MEMORY
91d253ca0cSRick Edgecombe	select ARCH_HAS_SET_DIRECT_MAP
92ad21fc4fSLaura Abbott	select ARCH_HAS_STRICT_KERNEL_RWX
93ad21fc4fSLaura Abbott	select ARCH_HAS_STRICT_MODULE_RWX
94ac1ab12aSMathieu Desnoyers	select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
9525c619e5SBrian Gerst	select ARCH_HAS_SYSCALL_WRAPPER
96c6d30853SAndrey Ryabinin	select ARCH_HAS_UBSAN_SANITIZE_ALL
977e01ccb4SZong Li	select ARCH_HAS_DEBUG_WX
9863703f37SKefeng Wang	select ARCH_HAS_ZONE_DMA_SET if EXPERT
996471b825SIngo Molnar	select ARCH_HAVE_NMI_SAFE_CMPXCHG
1006471b825SIngo Molnar	select ARCH_MIGHT_HAVE_ACPI_PDC		if ACPI
10177fbbc81SMark Salter	select ARCH_MIGHT_HAVE_PC_PARPORT
1025e2c18c0SMark Salter	select ARCH_MIGHT_HAVE_PC_SERIO
1033599fe12SThomas Gleixner	select ARCH_STACKWALK
1042c870e61SArnd Bergmann	select ARCH_SUPPORTS_ACPI
1056471b825SIngo Molnar	select ARCH_SUPPORTS_ATOMIC_RMW
1065d6ad668SMike Rapoport	select ARCH_SUPPORTS_DEBUG_PAGEALLOC
107d283d422SPasha Tatashin	select ARCH_SUPPORTS_PAGE_TABLE_CHECK	if X86_64
1086471b825SIngo Molnar	select ARCH_SUPPORTS_NUMA_BALANCING	if X86_64
10914df3267SThomas Gleixner	select ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP	if NR_CPUS <= 4096
110583bfd48SNathan Chancellor	select ARCH_SUPPORTS_LTO_CLANG
111583bfd48SNathan Chancellor	select ARCH_SUPPORTS_LTO_CLANG_THIN
1126471b825SIngo Molnar	select ARCH_USE_BUILTIN_BSWAP
113dce44566SAnshuman Khandual	select ARCH_USE_MEMTEST
1146471b825SIngo Molnar	select ARCH_USE_QUEUED_RWLOCKS
1156471b825SIngo Molnar	select ARCH_USE_QUEUED_SPINLOCKS
1162ce0d7f9SMark Brown	select ARCH_USE_SYM_ANNOTATIONS
117ce4a4e56SAndy Lutomirski	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
11881c22041SDaniel Borkmann	select ARCH_WANT_DEFAULT_BPF_JIT	if X86_64
119c763ea26SIngo Molnar	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
12051c2ee6dSNick Desaulniers	select ARCH_WANTS_NO_INSTR
121*07431506SAnshuman Khandual	select ARCH_WANT_GENERAL_HUGETLB
1223876d4a3SAlexandre Ghiti	select ARCH_WANT_HUGE_PMD_SHARE
12359612b24SNathan Chancellor	select ARCH_WANT_LD_ORPHAN_WARN
12438d8b4e6SHuang Ying	select ARCH_WANTS_THP_SWAP		if X86_64
125b5f06f64SBalbir Singh	select ARCH_HAS_PARANOID_L1D_FLUSH
12610916706SShile Zhang	select BUILDTIME_TABLE_SORT
1276471b825SIngo Molnar	select CLKEVT_I8253
1286471b825SIngo Molnar	select CLOCKSOURCE_VALIDATE_LAST_CYCLE
1296471b825SIngo Molnar	select CLOCKSOURCE_WATCHDOG
1306471b825SIngo Molnar	select DCACHE_WORD_ACCESS
1313aac3ebeSThomas Gleixner	select DYNAMIC_SIGFRAME
13245471cd9SLinus Torvalds	select EDAC_ATOMIC_SCRUB
13345471cd9SLinus Torvalds	select EDAC_SUPPORT
1346471b825SIngo Molnar	select GENERIC_CLOCKEVENTS_BROADCAST	if X86_64 || (X86_32 && X86_LOCAL_APIC)
1356471b825SIngo Molnar	select GENERIC_CLOCKEVENTS_MIN_ADJUST
1366471b825SIngo Molnar	select GENERIC_CMOS_UPDATE
1376471b825SIngo Molnar	select GENERIC_CPU_AUTOPROBE
13861dc0f55SThomas Gleixner	select GENERIC_CPU_VULNERABILITIES
1396471b825SIngo Molnar	select GENERIC_EARLY_IOREMAP
14027d6b4d1SThomas Gleixner	select GENERIC_ENTRY
1416471b825SIngo Molnar	select GENERIC_IOMAP
142c7d6c9ddSThomas Gleixner	select GENERIC_IRQ_EFFECTIVE_AFF_MASK	if SMP
1430fa115daSThomas Gleixner	select GENERIC_IRQ_MATRIX_ALLOCATOR	if X86_LOCAL_APIC
144ad7a929fSThomas Gleixner	select GENERIC_IRQ_MIGRATION		if SMP
1456471b825SIngo Molnar	select GENERIC_IRQ_PROBE
146c201c917SThomas Gleixner	select GENERIC_IRQ_RESERVATION_MODE
1476471b825SIngo Molnar	select GENERIC_IRQ_SHOW
1486471b825SIngo Molnar	select GENERIC_PENDING_IRQ		if SMP
1492ae27137SSteven Price	select GENERIC_PTDUMP
1506471b825SIngo Molnar	select GENERIC_SMP_IDLE_THREAD
1516471b825SIngo Molnar	select GENERIC_TIME_VSYSCALL
1527ac87074SVincenzo Frascino	select GENERIC_GETTIMEOFDAY
153550a77a7SDmitry Safonov	select GENERIC_VDSO_TIME_NS
15439656e83SChristoph Hellwig	select GUP_GET_PTE_LOW_HIGH		if X86_PAE
15517e5888eSHans de Goede	select HARDIRQS_SW_RESEND
1567edaeb68SThomas Gleixner	select HARDLOCKUP_CHECK_TIMESTAMP	if X86_64
1576471b825SIngo Molnar	select HAVE_ACPI_APEI			if ACPI
1586471b825SIngo Molnar	select HAVE_ACPI_APEI_NMI		if ACPI
1596471b825SIngo Molnar	select HAVE_ALIGNED_STRUCT_PAGE		if SLUB
1606471b825SIngo Molnar	select HAVE_ARCH_AUDITSYSCALL
1616471b825SIngo Molnar	select HAVE_ARCH_HUGE_VMAP		if X86_64 || X86_PAE
1626471b825SIngo Molnar	select HAVE_ARCH_JUMP_LABEL
163b34006c4SArd Biesheuvel	select HAVE_ARCH_JUMP_LABEL_RELATIVE
164d17a1d97SAndrey Ryabinin	select HAVE_ARCH_KASAN			if X86_64
1650609ae01SDaniel Axtens	select HAVE_ARCH_KASAN_VMALLOC		if X86_64
1661dc0da6eSAlexander Potapenko	select HAVE_ARCH_KFENCE
1676471b825SIngo Molnar	select HAVE_ARCH_KGDB
1689e08f57dSDaniel Cashman	select HAVE_ARCH_MMAP_RND_BITS		if MMU
1699e08f57dSDaniel Cashman	select HAVE_ARCH_MMAP_RND_COMPAT_BITS	if MMU && COMPAT
1701b028f78SDmitry Safonov	select HAVE_ARCH_COMPAT_MMAP_BASES	if MMU && COMPAT
171271ca788SArd Biesheuvel	select HAVE_ARCH_PREL32_RELOCATIONS
1726471b825SIngo Molnar	select HAVE_ARCH_SECCOMP_FILTER
173f7d83c1cSKees Cook	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
174afaef01cSAlexander Popov	select HAVE_ARCH_STACKLEAK
1756471b825SIngo Molnar	select HAVE_ARCH_TRACEHOOK
1766471b825SIngo Molnar	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
177a00cc7d9SMatthew Wilcox	select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
178b64d8d1eSPeter Xu	select HAVE_ARCH_USERFAULTFD_WP         if X86_64 && USERFAULTFD
1797677f7fdSAxel Rasmussen	select HAVE_ARCH_USERFAULTFD_MINOR	if X86_64 && USERFAULTFD
180e37e43a4SAndy Lutomirski	select HAVE_ARCH_VMAP_STACK		if X86_64
181fe950f60SKees Cook	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
182c763ea26SIngo Molnar	select HAVE_ARCH_WITHIN_STACK_FRAMES
1832ff2b7ecSMasahiro Yamada	select HAVE_ASM_MODVERSIONS
1846471b825SIngo Molnar	select HAVE_CMPXCHG_DOUBLE
1856471b825SIngo Molnar	select HAVE_CMPXCHG_LOCAL
1866471b825SIngo Molnar	select HAVE_CONTEXT_TRACKING		if X86_64
187d1f250e2SFrederic Weisbecker	select HAVE_CONTEXT_TRACKING_OFFSTACK	if HAVE_CONTEXT_TRACKING
1886471b825SIngo Molnar	select HAVE_C_RECORDMCOUNT
1896dafca97SSami Tolvanen	select HAVE_OBJTOOL_MCOUNT		if STACK_VALIDATION
1904ed308c4SSteven Rostedt (Google)	select HAVE_BUILDTIME_MCOUNT_SORT
1916471b825SIngo Molnar	select HAVE_DEBUG_KMEMLEAK
1929c5a3621SAkinobu Mita	select HAVE_DMA_CONTIGUOUS
193677aa9f7SSteven Rostedt	select HAVE_DYNAMIC_FTRACE
19406aeaaeaSMasami Hiramatsu	select HAVE_DYNAMIC_FTRACE_WITH_REGS
19502a474caSSteven Rostedt (VMware)	select HAVE_DYNAMIC_FTRACE_WITH_ARGS	if X86_64
196562955feSSteven Rostedt (VMware)	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
197c316eb44SHeiko Carstens	select HAVE_SAMPLE_FTRACE_DIRECT	if X86_64
198503e4510SHeiko Carstens	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI	if X86_64
19903f5781bSWang YanQing	select HAVE_EBPF_JIT
20058340a07SJohannes Berg	select HAVE_EFFICIENT_UNALIGNED_ACCESS
2016630a8e5SChristoph Hellwig	select HAVE_EISA
2025f56a5dfSJiri Slaby	select HAVE_EXIT_THREAD
20367a929e0SChristoph Hellwig	select HAVE_FAST_GUP
204644e0e8dSSteven Rostedt (VMware)	select HAVE_FENTRY			if X86_64 || DYNAMIC_FTRACE
2056471b825SIngo Molnar	select HAVE_FTRACE_MCOUNT_RECORD
2064a30e4c9SSteven Rostedt (VMware)	select HAVE_FUNCTION_GRAPH_TRACER	if X86_32 || (X86_64 && DYNAMIC_FTRACE)
2076471b825SIngo Molnar	select HAVE_FUNCTION_TRACER
2086b90bd4bSEmese Revfy	select HAVE_GCC_PLUGINS
2090067f129SK.Prasad	select HAVE_HW_BREAKPOINT
2106471b825SIngo Molnar	select HAVE_IOREMAP_PROT
211624db9eaSThomas Gleixner	select HAVE_IRQ_EXIT_ON_IRQ_STACK	if X86_64
2126471b825SIngo Molnar	select HAVE_IRQ_TIME_ACCOUNTING
2136471b825SIngo Molnar	select HAVE_KERNEL_BZIP2
2146471b825SIngo Molnar	select HAVE_KERNEL_GZIP
2156471b825SIngo Molnar	select HAVE_KERNEL_LZ4
2166471b825SIngo Molnar	select HAVE_KERNEL_LZMA
2176471b825SIngo Molnar	select HAVE_KERNEL_LZO
2186471b825SIngo Molnar	select HAVE_KERNEL_XZ
219fb46d057SNick Terrell	select HAVE_KERNEL_ZSTD
2206471b825SIngo Molnar	select HAVE_KPROBES
2216471b825SIngo Molnar	select HAVE_KPROBES_ON_FTRACE
222540adea3SMasami Hiramatsu	select HAVE_FUNCTION_ERROR_INJECTION
2236471b825SIngo Molnar	select HAVE_KRETPROBES
2246471b825SIngo Molnar	select HAVE_KVM
2256471b825SIngo Molnar	select HAVE_LIVEPATCH			if X86_64
2260102752eSFrederic Weisbecker	select HAVE_MIXED_BREAKPOINTS_REGS
227ee9f8fceSJosh Poimboeuf	select HAVE_MOD_ARCH_SPECIFIC
2289f132f7eSJoel Fernandes (Google)	select HAVE_MOVE_PMD
229be37c98dSKalesh Singh	select HAVE_MOVE_PUD
23042a0bb3fSPetr Mladek	select HAVE_NMI
2316471b825SIngo Molnar	select HAVE_OPTPROBES
2326471b825SIngo Molnar	select HAVE_PCSPKR_PLATFORM
2336471b825SIngo Molnar	select HAVE_PERF_EVENTS
234c01d4323SFrederic Weisbecker	select HAVE_PERF_EVENTS_NMI
23592e5aae4SNicholas Piggin	select HAVE_HARDLOCKUP_DETECTOR_PERF	if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
236eb01d42aSChristoph Hellwig	select HAVE_PCI
237c5e63197SJiri Olsa	select HAVE_PERF_REGS
238c5ebcedbSJiri Olsa	select HAVE_PERF_USER_STACK_DUMP
239ff2e6d72SPeter Zijlstra	select MMU_GATHER_RCU_TABLE_FREE		if PARAVIRT
24000998085SThomas Gleixner	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
2416471b825SIngo Molnar	select HAVE_REGS_AND_STACK_ACCESS_API
2426415b38bSJiri Slaby	select HAVE_RELIABLE_STACKTRACE		if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION
2433c88ee19SMasami Hiramatsu	select HAVE_FUNCTION_ARG_ACCESS_API
2447ecd19cfSKefeng Wang	select HAVE_SETUP_PER_CPU_AREA
245cd1a41ceSThomas Gleixner	select HAVE_SOFTIRQ_ON_OWN_STACK
246d148eac0SMasahiro Yamada	select HAVE_STACKPROTECTOR		if CC_HAS_SANE_STACKPROTECTOR
247c763ea26SIngo Molnar	select HAVE_STACK_VALIDATION		if X86_64
248e6d6c071SJosh Poimboeuf	select HAVE_STATIC_CALL
2491e7e4788SJosh Poimboeuf	select HAVE_STATIC_CALL_INLINE		if HAVE_STACK_VALIDATION
2506ef869e0SMichal Hocko	select HAVE_PREEMPT_DYNAMIC
251d6761b8fSMathieu Desnoyers	select HAVE_RSEQ
2526471b825SIngo Molnar	select HAVE_SYSCALL_TRACEPOINTS
2536471b825SIngo Molnar	select HAVE_UNSTABLE_SCHED_CLOCK
2547c68af6eSAvi Kivity	select HAVE_USER_RETURN_NOTIFIER
2557ac87074SVincenzo Frascino	select HAVE_GENERIC_VDSO
25605736e4aSThomas Gleixner	select HOTPLUG_SMT			if SMP
257c0185808SThomas Gleixner	select IRQ_FORCED_THREADING
2587ecd19cfSKefeng Wang	select NEED_PER_CPU_EMBED_FIRST_CHUNK
2597ecd19cfSKefeng Wang	select NEED_PER_CPU_PAGE_FIRST_CHUNK
26086596f0aSChristoph Hellwig	select NEED_SG_DMA_LENGTH
2612eac9c2dSChristoph Hellwig	select PCI_DOMAINS			if PCI
262625210cfSSinan Kaya	select PCI_LOCKLESS_CONFIG		if PCI
2636471b825SIngo Molnar	select PERF_EVENTS
2643195ef59SPrarit Bhargava	select RTC_LIB
265d6faca40SArnd Bergmann	select RTC_MC146818_LIB
2666471b825SIngo Molnar	select SPARSE_IRQ
26783fe27eaSPranith Kumar	select SRCU
2681e7e4788SJosh Poimboeuf	select STACK_VALIDATION			if HAVE_STACK_VALIDATION && (HAVE_STATIC_CALL_INLINE || RETPOLINE)
2696471b825SIngo Molnar	select SYSCTL_EXCEPTION_TRACE
27015f4eae7SAndy Lutomirski	select THREAD_INFO_IN_TASK
2714aae683fSMasahiro Yamada	select TRACE_IRQFLAGS_SUPPORT
2726471b825SIngo Molnar	select USER_STACKTRACE_SUPPORT
2736471b825SIngo Molnar	select VIRT_TO_BUS
2743b02a051SIngo Molnar	select HAVE_ARCH_KCSAN			if X86_64
2756471b825SIngo Molnar	select X86_FEATURE_NAMES		if PROC_FS
2760c608dadSAubrey Li	select PROC_PID_ARCH_STATUS		if PROC_FS
27750468e43SJarkko Sakkinen	select HAVE_ARCH_NODE_DEV_GROUP		if X86_SGX
2789e2b4be3SNayna Jain	imply IMA_SECURE_AND_OR_TRUSTED_BOOT    if EFI
2797d8330a5SBalbir Singh
280ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER
2813120e25eSJan Beulich	def_bool y
2823120e25eSJan Beulich	depends on KPROBES || PERF_EVENTS || UPROBES
283ba7e4d13SIngo Molnar
28451b26adaSLinus Torvaldsconfig OUTPUT_FORMAT
28551b26adaSLinus Torvalds	string
28651b26adaSLinus Torvalds	default "elf32-i386" if X86_32
28751b26adaSLinus Torvalds	default "elf64-x86-64" if X86_64
28851b26adaSLinus Torvalds
2898d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT
2903c2362e6SHarvey Harrison	def_bool y
2918d5fffb9SSam Ravnborg
2928d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT
2933c2362e6SHarvey Harrison	def_bool y
2948d5fffb9SSam Ravnborg
2958d5fffb9SSam Ravnborgconfig MMU
2963c2362e6SHarvey Harrison	def_bool y
2978d5fffb9SSam Ravnborg
2989e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN
2999e08f57dSDaniel Cashman	default 28 if 64BIT
3009e08f57dSDaniel Cashman	default 8
3019e08f57dSDaniel Cashman
3029e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX
3039e08f57dSDaniel Cashman	default 32 if 64BIT
3049e08f57dSDaniel Cashman	default 16
3059e08f57dSDaniel Cashman
3069e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN
3079e08f57dSDaniel Cashman	default 8
3089e08f57dSDaniel Cashman
3099e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX
3109e08f57dSDaniel Cashman	default 16
3119e08f57dSDaniel Cashman
3128d5fffb9SSam Ravnborgconfig SBUS
3138d5fffb9SSam Ravnborg	bool
3148d5fffb9SSam Ravnborg
3158d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA
3163120e25eSJan Beulich	def_bool y
3173120e25eSJan Beulich	depends on ISA_DMA_API
3188d5fffb9SSam Ravnborg
3198d5fffb9SSam Ravnborgconfig GENERIC_BUG
3203c2362e6SHarvey Harrison	def_bool y
3218d5fffb9SSam Ravnborg	depends on BUG
322b93a531eSJan Beulich	select GENERIC_BUG_RELATIVE_POINTERS if X86_64
323b93a531eSJan Beulich
324b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS
325b93a531eSJan Beulich	bool
3268d5fffb9SSam Ravnborg
3278d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC
3283120e25eSJan Beulich	def_bool y
3293120e25eSJan Beulich	depends on ISA_DMA_API
3308d5fffb9SSam Ravnborg
3311032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY
3321032c0baSSam Ravnborg	def_bool y
3331032c0baSSam Ravnborg
3349a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX
3359a0b8415Svenkatesh.pallipadi@intel.com	def_bool y
3368d5fffb9SSam Ravnborg
337316d097cSDave Hansenconfig ARCH_HAS_FILTER_PGPROT
338316d097cSDave Hansen	def_bool y
339316d097cSDave Hansen
340801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE
341801e4062SJohannes Berg	def_bool y
342801e4062SJohannes Berg
343d7109fe3SAndy Shevchenkoconfig ARCH_NR_GPIO
344d7109fe3SAndy Shevchenko	int
345d7109fe3SAndy Shevchenko	default 1024 if X86_64
346d7109fe3SAndy Shevchenko	default 512
347d7109fe3SAndy Shevchenko
348f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE
349f4cb5700SJohannes Berg	def_bool y
350f4cb5700SJohannes Berg
3518d5fffb9SSam Ravnborgconfig AUDIT_ARCH
352e0fd24a3SJan Beulich	def_bool y if X86_64
3538d5fffb9SSam Ravnborg
354d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET
355d6f2d75aSAndrey Ryabinin	hex
356d6f2d75aSAndrey Ryabinin	depends on KASAN
357d6f2d75aSAndrey Ryabinin	default 0xdffffc0000000000
358d6f2d75aSAndrey Ryabinin
35969575d38SShane Wangconfig HAVE_INTEL_TXT
36069575d38SShane Wang	def_bool y
3616ea30386SKees Cook	depends on INTEL_IOMMU && ACPI
36269575d38SShane Wang
3636b0c3d44SSam Ravnborgconfig X86_32_SMP
3646b0c3d44SSam Ravnborg	def_bool y
3656b0c3d44SSam Ravnborg	depends on X86_32 && SMP
3666b0c3d44SSam Ravnborg
3676b0c3d44SSam Ravnborgconfig X86_64_SMP
3686b0c3d44SSam Ravnborg	def_bool y
3696b0c3d44SSam Ravnborg	depends on X86_64 && SMP
3706b0c3d44SSam Ravnborg
3712b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES
3722b144498SSrikar Dronamraju	def_bool y
3732b144498SSrikar Dronamraju
374d20642f0SRob Herringconfig FIX_EARLYCON_MEM
375d20642f0SRob Herring	def_bool y
376d20642f0SRob Herring
37794d49eb3SKirill A. Shutemovconfig DYNAMIC_PHYSICAL_MASK
37894d49eb3SKirill A. Shutemov	bool
37994d49eb3SKirill A. Shutemov
38098233368SKirill A. Shutemovconfig PGTABLE_LEVELS
38198233368SKirill A. Shutemov	int
38277ef56e4SKirill A. Shutemov	default 5 if X86_5LEVEL
38398233368SKirill A. Shutemov	default 4 if X86_64
38498233368SKirill A. Shutemov	default 3 if X86_PAE
38598233368SKirill A. Shutemov	default 2
38698233368SKirill A. Shutemov
3872a61f474SMasahiro Yamadaconfig CC_HAS_SANE_STACKPROTECTOR
3882a61f474SMasahiro Yamada	bool
3892a61f474SMasahiro Yamada	default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
3902a61f474SMasahiro Yamada	default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
3912a61f474SMasahiro Yamada	help
3922a61f474SMasahiro Yamada	   We have to make sure stack protector is unconditionally disabled if
3933fb0fdb3SAndy Lutomirski	   the compiler produces broken code or if it does not let us control
3943fb0fdb3SAndy Lutomirski	   the segment on 32-bit kernels.
3952a61f474SMasahiro Yamada
396506f1d07SSam Ravnborgmenu "Processor type and features"
397506f1d07SSam Ravnborg
398506f1d07SSam Ravnborgconfig SMP
399506f1d07SSam Ravnborg	bool "Symmetric multi-processing support"
400a7f7f624SMasahiro Yamada	help
401506f1d07SSam Ravnborg	  This enables support for systems with more than one CPU. If you have
4024a474157SRobert Graffham	  a system with only one CPU, say N. If you have a system with more
4034a474157SRobert Graffham	  than one CPU, say Y.
404506f1d07SSam Ravnborg
4054a474157SRobert Graffham	  If you say N here, the kernel will run on uni- and multiprocessor
406506f1d07SSam Ravnborg	  machines, but will use only one CPU of a multiprocessor machine. If
407506f1d07SSam Ravnborg	  you say Y here, the kernel will run on many, but not all,
4084a474157SRobert Graffham	  uniprocessor machines. On a uniprocessor machine, the kernel
409506f1d07SSam Ravnborg	  will run faster if you say N here.
410506f1d07SSam Ravnborg
411506f1d07SSam Ravnborg	  Note that if you say Y here and choose architecture "586" or
412506f1d07SSam Ravnborg	  "Pentium" under "Processor family", the kernel will not work on 486
413506f1d07SSam Ravnborg	  architectures. Similarly, multiprocessor kernels for the "PPro"
414506f1d07SSam Ravnborg	  architecture may not work on all Pentium based boards.
415506f1d07SSam Ravnborg
416506f1d07SSam Ravnborg	  People using multiprocessor machines who say Y here should also say
417506f1d07SSam Ravnborg	  Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
418506f1d07SSam Ravnborg	  Management" code will be disabled if you say Y here.
419506f1d07SSam Ravnborg
420cb1aaebeSMauro Carvalho Chehab	  See also <file:Documentation/x86/i386/IO-APIC.rst>,
4214f4cfa6cSMauro Carvalho Chehab	  <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
422506f1d07SSam Ravnborg	  <http://www.tldp.org/docs.html#howto>.
423506f1d07SSam Ravnborg
424506f1d07SSam Ravnborg	  If you don't know what to do here, say N.
425506f1d07SSam Ravnborg
4269def39beSJosh Triplettconfig X86_FEATURE_NAMES
4279def39beSJosh Triplett	bool "Processor feature human-readable names" if EMBEDDED
4289def39beSJosh Triplett	default y
429a7f7f624SMasahiro Yamada	help
4309def39beSJosh Triplett	  This option compiles in a table of x86 feature bits and corresponding
4319def39beSJosh Triplett	  names.  This is required to support /proc/cpuinfo and a few kernel
4329def39beSJosh Triplett	  messages.  You can disable this to save space, at the expense of
4339def39beSJosh Triplett	  making those few kernel messages show numeric feature bits instead.
4349def39beSJosh Triplett
4359def39beSJosh Triplett	  If in doubt, say Y.
4369def39beSJosh Triplett
43706cd9a7dSYinghai Luconfig X86_X2APIC
43806cd9a7dSYinghai Lu	bool "Support x2apic"
43919e3d60dSJan Kiszka	depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
440a7f7f624SMasahiro Yamada	help
44106cd9a7dSYinghai Lu	  This enables x2apic support on CPUs that have this feature.
44206cd9a7dSYinghai Lu
44306cd9a7dSYinghai Lu	  This allows 32-bit apic IDs (so it can support very large systems),
44406cd9a7dSYinghai Lu	  and accesses the local apic via MSRs not via mmio.
44506cd9a7dSYinghai Lu
44606cd9a7dSYinghai Lu	  If you don't know what to do here, say N.
44706cd9a7dSYinghai Lu
4486695c85bSYinghai Luconfig X86_MPPARSE
4494590d98fSAndy Shevchenko	bool "Enable MPS table" if ACPI
4507a527688SJan Beulich	default y
4515ab74722SIngo Molnar	depends on X86_LOCAL_APIC
452a7f7f624SMasahiro Yamada	help
4536695c85bSYinghai Lu	  For old smp systems that do not have proper acpi support. Newer systems
4546695c85bSYinghai Lu	  (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
4556695c85bSYinghai Lu
456ddd70cf9SJun Nakajimaconfig GOLDFISH
457ddd70cf9SJun Nakajima	def_bool y
458ddd70cf9SJun Nakajima	depends on X86_GOLDFISH
459ddd70cf9SJun Nakajima
46076b04384SDavid Woodhouseconfig RETPOLINE
46176b04384SDavid Woodhouse	bool "Avoid speculative indirect branches in kernel"
46276b04384SDavid Woodhouse	default y
46376b04384SDavid Woodhouse	help
46476b04384SDavid Woodhouse	  Compile kernel with the retpoline compiler options to guard against
46576b04384SDavid Woodhouse	  kernel-to-user data leaks by avoiding speculative indirect
46676b04384SDavid Woodhouse	  branches. Requires a compiler with -mindirect-branch=thunk-extern
46776b04384SDavid Woodhouse	  support for full protection. The kernel may run slower.
46876b04384SDavid Woodhouse
469e463a09aSPeter Zijlstraconfig CC_HAS_SLS
470e463a09aSPeter Zijlstra	def_bool $(cc-option,-mharden-sls=all)
471e463a09aSPeter Zijlstra
472e463a09aSPeter Zijlstraconfig SLS
473e463a09aSPeter Zijlstra	bool "Mitigate Straight-Line-Speculation"
474e463a09aSPeter Zijlstra	depends on CC_HAS_SLS && X86_64
475e463a09aSPeter Zijlstra	default n
476e463a09aSPeter Zijlstra	help
477e463a09aSPeter Zijlstra	  Compile the kernel with straight-line-speculation options to guard
478e463a09aSPeter Zijlstra	  against straight line speculation. The kernel image might be slightly
479e463a09aSPeter Zijlstra	  larger.
480e463a09aSPeter Zijlstra
481e6d42931SJohannes Weinerconfig X86_CPU_RESCTRL
482e6d42931SJohannes Weiner	bool "x86 CPU resource control support"
4836fe07ce3SBabu Moger	depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
48459fe5a77SThomas Gleixner	select KERNFS
485e79f15a4SChen Yu	select PROC_CPU_RESCTRL		if PROC_FS
48678e99b4aSFenghua Yu	help
487e6d42931SJohannes Weiner	  Enable x86 CPU resource control support.
4886fe07ce3SBabu Moger
4896fe07ce3SBabu Moger	  Provide support for the allocation and monitoring of system resources
4906fe07ce3SBabu Moger	  usage by the CPU.
4916fe07ce3SBabu Moger
4926fe07ce3SBabu Moger	  Intel calls this Intel Resource Director Technology
4936fe07ce3SBabu Moger	  (Intel(R) RDT). More information about RDT can be found in the
4946fe07ce3SBabu Moger	  Intel x86 Architecture Software Developer Manual.
4956fe07ce3SBabu Moger
4966fe07ce3SBabu Moger	  AMD calls this AMD Platform Quality of Service (AMD QoS).
4976fe07ce3SBabu Moger	  More information about AMD QoS can be found in the AMD64 Technology
4986fe07ce3SBabu Moger	  Platform Quality of Service Extensions manual.
49978e99b4aSFenghua Yu
50078e99b4aSFenghua Yu	  Say N if unsure.
50178e99b4aSFenghua Yu
5028425091fSRavikiran G Thirumalaiif X86_32
503a0d0bb4dSRandy Dunlapconfig X86_BIGSMP
504a0d0bb4dSRandy Dunlap	bool "Support for big SMP systems with more than 8 CPUs"
505a0d0bb4dSRandy Dunlap	depends on SMP
506a7f7f624SMasahiro Yamada	help
507e133f6eaSRandy Dunlap	  This option is needed for the systems that have more than 8 CPUs.
508a0d0bb4dSRandy Dunlap
509c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM
510c5c606d9SRavikiran G Thirumalai	bool "Support for extended (non-PC) x86 platforms"
511c5c606d9SRavikiran G Thirumalai	default y
512a7f7f624SMasahiro Yamada	help
51306ac8346SIngo Molnar	  If you disable this option then the kernel will only support
51406ac8346SIngo Molnar	  standard PC platforms. (which covers the vast majority of
51506ac8346SIngo Molnar	  systems out there.)
51606ac8346SIngo Molnar
5178425091fSRavikiran G Thirumalai	  If you enable this option then you'll be able to select support
5188425091fSRavikiran G Thirumalai	  for the following (non-PC) 32 bit x86 platforms:
519cb7b8023SBen Hutchings		Goldfish (Android emulator)
5208425091fSRavikiran G Thirumalai		AMD Elan
5218425091fSRavikiran G Thirumalai		RDC R-321x SoC
5228425091fSRavikiran G Thirumalai		SGI 320/540 (Visual Workstation)
52383125a3aSAlessandro Rubini		STA2X11-based (e.g. Northville)
5243f4110a4SThomas Gleixner		Moorestown MID devices
52506ac8346SIngo Molnar
52606ac8346SIngo Molnar	  If you have one of these systems, or if you want to build a
52706ac8346SIngo Molnar	  generic distribution kernel, say Y here - otherwise say N.
5288425091fSRavikiran G Thirumalaiendif
52906ac8346SIngo Molnar
5308425091fSRavikiran G Thirumalaiif X86_64
5318425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM
5328425091fSRavikiran G Thirumalai	bool "Support for extended (non-PC) x86 platforms"
5338425091fSRavikiran G Thirumalai	default y
534a7f7f624SMasahiro Yamada	help
5358425091fSRavikiran G Thirumalai	  If you disable this option then the kernel will only support
5368425091fSRavikiran G Thirumalai	  standard PC platforms. (which covers the vast majority of
5378425091fSRavikiran G Thirumalai	  systems out there.)
5388425091fSRavikiran G Thirumalai
5398425091fSRavikiran G Thirumalai	  If you enable this option then you'll be able to select support
5408425091fSRavikiran G Thirumalai	  for the following (non-PC) 64 bit x86 platforms:
54144b111b5SSteffen Persvold		Numascale NumaChip
5428425091fSRavikiran G Thirumalai		ScaleMP vSMP
5438425091fSRavikiran G Thirumalai		SGI Ultraviolet
5448425091fSRavikiran G Thirumalai
5458425091fSRavikiran G Thirumalai	  If you have one of these systems, or if you want to build a
5468425091fSRavikiran G Thirumalai	  generic distribution kernel, say Y here - otherwise say N.
5478425091fSRavikiran G Thirumalaiendif
548c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms
549c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions
55044b111b5SSteffen Persvoldconfig X86_NUMACHIP
55144b111b5SSteffen Persvold	bool "Numascale NumaChip"
55244b111b5SSteffen Persvold	depends on X86_64
55344b111b5SSteffen Persvold	depends on X86_EXTENDED_PLATFORM
55444b111b5SSteffen Persvold	depends on NUMA
55544b111b5SSteffen Persvold	depends on SMP
55644b111b5SSteffen Persvold	depends on X86_X2APIC
557f9726bfdSDaniel J Blueman	depends on PCI_MMCONFIG
558a7f7f624SMasahiro Yamada	help
55944b111b5SSteffen Persvold	  Adds support for Numascale NumaChip large-SMP systems. Needed to
56044b111b5SSteffen Persvold	  enable more than ~168 cores.
56144b111b5SSteffen Persvold	  If you don't have one of these, you should say N here.
56203b48632SNick Piggin
5636a48565eSIngo Molnarconfig X86_VSMP
564c5c606d9SRavikiran G Thirumalai	bool "ScaleMP vSMP"
5656276a074SBorislav Petkov	select HYPERVISOR_GUEST
5666a48565eSIngo Molnar	select PARAVIRT
5676a48565eSIngo Molnar	depends on X86_64 && PCI
568c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
569ead91d4bSShai Fultheim	depends on SMP
570a7f7f624SMasahiro Yamada	help
5716a48565eSIngo Molnar	  Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
5726a48565eSIngo Molnar	  supposed to run on these EM64T-based machines.  Only choose this option
5736a48565eSIngo Molnar	  if you have one of these machines.
5746a48565eSIngo Molnar
575c5c606d9SRavikiran G Thirumalaiconfig X86_UV
576c5c606d9SRavikiran G Thirumalai	bool "SGI Ultraviolet"
577c5c606d9SRavikiran G Thirumalai	depends on X86_64
578c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
57954c28d29SJack Steiner	depends on NUMA
5801ecb4ae5SAndrew Morton	depends on EFI
581c2209ea5SIngo Molnar	depends on KEXEC_CORE
5829d6c26e7SSuresh Siddha	depends on X86_X2APIC
5831222e564SIngo Molnar	depends on PCI
584a7f7f624SMasahiro Yamada	help
585c5c606d9SRavikiran G Thirumalai	  This option is needed in order to support SGI Ultraviolet systems.
586c5c606d9SRavikiran G Thirumalai	  If you don't have one of these, you should say N here.
587c5c606d9SRavikiran G Thirumalai
588c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms
589c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions
590506f1d07SSam Ravnborg
591ddd70cf9SJun Nakajimaconfig X86_GOLDFISH
592ddd70cf9SJun Nakajima	bool "Goldfish (Virtual Platform)"
593cb7b8023SBen Hutchings	depends on X86_EXTENDED_PLATFORM
594a7f7f624SMasahiro Yamada	help
595ddd70cf9SJun Nakajima	 Enable support for the Goldfish virtual platform used primarily
596ddd70cf9SJun Nakajima	 for Android development. Unless you are building for the Android
597ddd70cf9SJun Nakajima	 Goldfish emulator say N here.
598ddd70cf9SJun Nakajima
599c751e17bSThomas Gleixnerconfig X86_INTEL_CE
600c751e17bSThomas Gleixner	bool "CE4100 TV platform"
601c751e17bSThomas Gleixner	depends on PCI
602c751e17bSThomas Gleixner	depends on PCI_GODIRECT
6036084a6e2SJiang Liu	depends on X86_IO_APIC
604c751e17bSThomas Gleixner	depends on X86_32
605c751e17bSThomas Gleixner	depends on X86_EXTENDED_PLATFORM
60637bc9f50SDirk Brandewie	select X86_REBOOTFIXUPS
607da6b737bSSebastian Andrzej Siewior	select OF
608da6b737bSSebastian Andrzej Siewior	select OF_EARLY_FLATTREE
609a7f7f624SMasahiro Yamada	help
610c751e17bSThomas Gleixner	  Select for the Intel CE media processor (CE4100) SOC.
611c751e17bSThomas Gleixner	  This option compiles in support for the CE4100 SOC for settop
612c751e17bSThomas Gleixner	  boxes and media devices.
613c751e17bSThomas Gleixner
6144cb9b00fSDavid Cohenconfig X86_INTEL_MID
61543605ef1SAlan Cox	bool "Intel MID platform support"
61643605ef1SAlan Cox	depends on X86_EXTENDED_PLATFORM
617edc6bc78SDavid Cohen	depends on X86_PLATFORM_DEVICES
6181ea7c673SAlan Cox	depends on PCI
6193fda5bb4SAndy Shevchenko	depends on X86_64 || (PCI_GOANY && X86_32)
6201ea7c673SAlan Cox	depends on X86_IO_APIC
6214cb9b00fSDavid Cohen	select I2C
6227c9c3a1eSAlan Cox	select DW_APB_TIMER
62354b34aa0SMika Westerberg	select INTEL_SCU_PCI
624a7f7f624SMasahiro Yamada	help
6254cb9b00fSDavid Cohen	  Select to build a kernel capable of supporting Intel MID (Mobile
6264cb9b00fSDavid Cohen	  Internet Device) platform systems which do not have the PCI legacy
6274cb9b00fSDavid Cohen	  interfaces. If you are building for a PC class system say N here.
6281ea7c673SAlan Cox
6294cb9b00fSDavid Cohen	  Intel MID platforms are based on an Intel processor and chipset which
6304cb9b00fSDavid Cohen	  consume less power than most of the x86 derivatives.
63143605ef1SAlan Cox
6328bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK
6338bbc2a13SBryan O'Donoghue	bool "Intel Quark platform support"
6348bbc2a13SBryan O'Donoghue	depends on X86_32
6358bbc2a13SBryan O'Donoghue	depends on X86_EXTENDED_PLATFORM
6368bbc2a13SBryan O'Donoghue	depends on X86_PLATFORM_DEVICES
6378bbc2a13SBryan O'Donoghue	depends on X86_TSC
6388bbc2a13SBryan O'Donoghue	depends on PCI
6398bbc2a13SBryan O'Donoghue	depends on PCI_GOANY
6408bbc2a13SBryan O'Donoghue	depends on X86_IO_APIC
6418bbc2a13SBryan O'Donoghue	select IOSF_MBI
6428bbc2a13SBryan O'Donoghue	select INTEL_IMR
6439ab6eb51SAndy Shevchenko	select COMMON_CLK
644a7f7f624SMasahiro Yamada	help
6458bbc2a13SBryan O'Donoghue	  Select to include support for Quark X1000 SoC.
6468bbc2a13SBryan O'Donoghue	  Say Y here if you have a Quark based system such as the Arduino
6478bbc2a13SBryan O'Donoghue	  compatible Intel Galileo.
6488bbc2a13SBryan O'Donoghue
6493d48aab1SMika Westerbergconfig X86_INTEL_LPSS
6503d48aab1SMika Westerberg	bool "Intel Low Power Subsystem Support"
6515962dd22SSinan Kaya	depends on X86 && ACPI && PCI
6523d48aab1SMika Westerberg	select COMMON_CLK
6530f531431SMathias Nyman	select PINCTRL
654eebb3e8dSAndy Shevchenko	select IOSF_MBI
655a7f7f624SMasahiro Yamada	help
6563d48aab1SMika Westerberg	  Select to build support for Intel Low Power Subsystem such as
6573d48aab1SMika Westerberg	  found on Intel Lynxpoint PCH. Selecting this option enables
6580f531431SMathias Nyman	  things like clock tree (common clock framework) and pincontrol
6590f531431SMathias Nyman	  which are needed by the LPSS peripheral drivers.
6603d48aab1SMika Westerberg
66192082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE
66292082a88SKen Xue	bool "AMD ACPI2Platform devices support"
66392082a88SKen Xue	depends on ACPI
66492082a88SKen Xue	select COMMON_CLK
66592082a88SKen Xue	select PINCTRL
666a7f7f624SMasahiro Yamada	help
66792082a88SKen Xue	  Select to interpret AMD specific ACPI device to platform device
66892082a88SKen Xue	  such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
66992082a88SKen Xue	  I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
67092082a88SKen Xue	  implemented under PINCTRL subsystem.
67192082a88SKen Xue
672ced3ce76SDavid E. Boxconfig IOSF_MBI
673ced3ce76SDavid E. Box	tristate "Intel SoC IOSF Sideband support for SoC platforms"
674ced3ce76SDavid E. Box	depends on PCI
675a7f7f624SMasahiro Yamada	help
676ced3ce76SDavid E. Box	  This option enables sideband register access support for Intel SoC
677ced3ce76SDavid E. Box	  platforms. On these platforms the IOSF sideband is used in lieu of
678ced3ce76SDavid E. Box	  MSR's for some register accesses, mostly but not limited to thermal
679ced3ce76SDavid E. Box	  and power. Drivers may query the availability of this device to
680ced3ce76SDavid E. Box	  determine if they need the sideband in order to work on these
681ced3ce76SDavid E. Box	  platforms. The sideband is available on the following SoC products.
682ced3ce76SDavid E. Box	  This list is not meant to be exclusive.
683ced3ce76SDavid E. Box	   - BayTrail
684ced3ce76SDavid E. Box	   - Braswell
685ced3ce76SDavid E. Box	   - Quark
686ced3ce76SDavid E. Box
687ced3ce76SDavid E. Box	  You should say Y if you are running a kernel on one of these SoC's.
688ced3ce76SDavid E. Box
689ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG
690ed2226bdSDavid E. Box	bool "Enable IOSF sideband access through debugfs"
691ed2226bdSDavid E. Box	depends on IOSF_MBI && DEBUG_FS
692a7f7f624SMasahiro Yamada	help
693ed2226bdSDavid E. Box	  Select this option to expose the IOSF sideband access registers (MCR,
694ed2226bdSDavid E. Box	  MDR, MCRX) through debugfs to write and read register information from
695ed2226bdSDavid E. Box	  different units on the SoC. This is most useful for obtaining device
696ed2226bdSDavid E. Box	  state information for debug and analysis. As this is a general access
697ed2226bdSDavid E. Box	  mechanism, users of this option would have specific knowledge of the
698ed2226bdSDavid E. Box	  device they want to access.
699ed2226bdSDavid E. Box
700ed2226bdSDavid E. Box	  If you don't require the option or are in doubt, say N.
701ed2226bdSDavid E. Box
702c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X
703c5c606d9SRavikiran G Thirumalai	bool "RDC R-321x SoC"
704506f1d07SSam Ravnborg	depends on X86_32
705c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
706c5c606d9SRavikiran G Thirumalai	select M486
707c5c606d9SRavikiran G Thirumalai	select X86_REBOOTFIXUPS
708a7f7f624SMasahiro Yamada	help
709c5c606d9SRavikiran G Thirumalai	  This option is needed for RDC R-321x system-on-chip, also known
710c5c606d9SRavikiran G Thirumalai	  as R-8610-(G).
711c5c606d9SRavikiran G Thirumalai	  If you don't have one of these chips, you should say N here.
712c5c606d9SRavikiran G Thirumalai
713e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD
7149c398017SIngo Molnar	bool "Support non-standard 32-bit SMP architectures"
7159c398017SIngo Molnar	depends on X86_32 && SMP
716c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
717a7f7f624SMasahiro Yamada	help
718b5660ba7SH. Peter Anvin	  This option compiles in the bigsmp and STA2X11 default
719b5660ba7SH. Peter Anvin	  subarchitectures.  It is intended for a generic binary
720b5660ba7SH. Peter Anvin	  kernel. If you select them all, kernel will probe it one by
721b5660ba7SH. Peter Anvin	  one and will fallback to default.
722d49c4288SYinghai Lu
723c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms
724d49c4288SYinghai Lu
725d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE
7266fc108a0SJan Beulich	def_bool y
727d949f36fSLinus Torvalds	# MCE code calls memory_failure():
728d949f36fSLinus Torvalds	depends on X86_MCE
729d949f36fSLinus Torvalds	# On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
730d949f36fSLinus Torvalds	# On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
731d949f36fSLinus Torvalds	depends on X86_64 || !SPARSEMEM
732d949f36fSLinus Torvalds	select ARCH_SUPPORTS_MEMORY_FAILURE
733d949f36fSLinus Torvalds
73483125a3aSAlessandro Rubiniconfig STA2X11
73583125a3aSAlessandro Rubini	bool "STA2X11 Companion Chip Support"
73683125a3aSAlessandro Rubini	depends on X86_32_NON_STANDARD && PCI
73783125a3aSAlessandro Rubini	select SWIOTLB
73883125a3aSAlessandro Rubini	select MFD_STA2X11
7390145071bSLinus Walleij	select GPIOLIB
740a7f7f624SMasahiro Yamada	help
74183125a3aSAlessandro Rubini	  This adds support for boards based on the STA2X11 IO-Hub,
74283125a3aSAlessandro Rubini	  a.k.a. "ConneXt". The chip is used in place of the standard
74383125a3aSAlessandro Rubini	  PC chipset, so all "standard" peripherals are missing. If this
74483125a3aSAlessandro Rubini	  option is selected the kernel will still be able to boot on
74583125a3aSAlessandro Rubini	  standard PC machines.
74683125a3aSAlessandro Rubini
74782148d1dSShérabconfig X86_32_IRIS
74882148d1dSShérab	tristate "Eurobraille/Iris poweroff module"
74982148d1dSShérab	depends on X86_32
750a7f7f624SMasahiro Yamada	help
75182148d1dSShérab	  The Iris machines from EuroBraille do not have APM or ACPI support
75282148d1dSShérab	  to shut themselves down properly.  A special I/O sequence is
75382148d1dSShérab	  needed to do so, which is what this module does at
75482148d1dSShérab	  kernel shutdown.
75582148d1dSShérab
75682148d1dSShérab	  This is only for Iris machines from EuroBraille.
75782148d1dSShérab
75882148d1dSShérab	  If unused, say N.
75982148d1dSShérab
760ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER
7613c2362e6SHarvey Harrison	def_bool y
7623c2362e6SHarvey Harrison	prompt "Single-depth WCHAN output"
763a87d0914SKen Chen	depends on X86
764a7f7f624SMasahiro Yamada	help
765506f1d07SSam Ravnborg	  Calculate simpler /proc/<PID>/wchan values. If this option
766506f1d07SSam Ravnborg	  is disabled then wchan values will recurse back to the
767506f1d07SSam Ravnborg	  caller function. This provides more accurate wchan values,
768506f1d07SSam Ravnborg	  at the expense of slightly more scheduling overhead.
769506f1d07SSam Ravnborg
770506f1d07SSam Ravnborg	  If in doubt, say "Y".
771506f1d07SSam Ravnborg
7726276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST
7736276a074SBorislav Petkov	bool "Linux guest support"
774a7f7f624SMasahiro Yamada	help
7756276a074SBorislav Petkov	  Say Y here to enable options for running Linux under various hyper-
7766276a074SBorislav Petkov	  visors. This option enables basic hypervisor detection and platform
7776276a074SBorislav Petkov	  setup.
778506f1d07SSam Ravnborg
7796276a074SBorislav Petkov	  If you say N, all options in this submenu will be skipped and
7806276a074SBorislav Petkov	  disabled, and Linux guest support won't be built in.
781506f1d07SSam Ravnborg
7826276a074SBorislav Petkovif HYPERVISOR_GUEST
783506f1d07SSam Ravnborg
784e61bd94aSEduardo Pereira Habkostconfig PARAVIRT
785e61bd94aSEduardo Pereira Habkost	bool "Enable paravirtualization code"
786a0e2bf7cSJuergen Gross	depends on HAVE_STATIC_CALL
787a7f7f624SMasahiro Yamada	help
788e61bd94aSEduardo Pereira Habkost	  This changes the kernel so it can modify itself when it is run
789e61bd94aSEduardo Pereira Habkost	  under a hypervisor, potentially improving performance significantly
790e61bd94aSEduardo Pereira Habkost	  over full virtualization.  However, when run without a hypervisor
791e61bd94aSEduardo Pereira Habkost	  the kernel is theoretically slower and slightly larger.
792e61bd94aSEduardo Pereira Habkost
793c00a280aSJuergen Grossconfig PARAVIRT_XXL
794c00a280aSJuergen Gross	bool
795c00a280aSJuergen Gross
7966276a074SBorislav Petkovconfig PARAVIRT_DEBUG
7976276a074SBorislav Petkov	bool "paravirt-ops debugging"
7986276a074SBorislav Petkov	depends on PARAVIRT && DEBUG_KERNEL
799a7f7f624SMasahiro Yamada	help
8006276a074SBorislav Petkov	  Enable to debug paravirt_ops internals.  Specifically, BUG if
8016276a074SBorislav Petkov	  a paravirt_op is missing when it is called.
8026276a074SBorislav Petkov
803b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS
804b4ecc126SJeremy Fitzhardinge	bool "Paravirtualization layer for spinlocks"
8056ea30386SKees Cook	depends on PARAVIRT && SMP
806a7f7f624SMasahiro Yamada	help
807b4ecc126SJeremy Fitzhardinge	  Paravirtualized spinlocks allow a pvops backend to replace the
808b4ecc126SJeremy Fitzhardinge	  spinlock implementation with something virtualization-friendly
809b4ecc126SJeremy Fitzhardinge	  (for example, block the virtual CPU rather than spinning).
810b4ecc126SJeremy Fitzhardinge
8114c4e4f61SRaghavendra K T	  It has a minimal impact on native kernels and gives a nice performance
8124c4e4f61SRaghavendra K T	  benefit on paravirtualized KVM / Xen kernels.
813b4ecc126SJeremy Fitzhardinge
8144c4e4f61SRaghavendra K T	  If you are unsure how to answer this question, answer Y.
815b4ecc126SJeremy Fitzhardinge
816ecca2502SZhao Yakuiconfig X86_HV_CALLBACK_VECTOR
817ecca2502SZhao Yakui	def_bool n
818ecca2502SZhao Yakui
8196276a074SBorislav Petkovsource "arch/x86/xen/Kconfig"
8206276a074SBorislav Petkov
8216276a074SBorislav Petkovconfig KVM_GUEST
8226276a074SBorislav Petkov	bool "KVM Guest support (including kvmclock)"
8236276a074SBorislav Petkov	depends on PARAVIRT
8246276a074SBorislav Petkov	select PARAVIRT_CLOCK
825a1c4423bSMarcelo Tosatti	select ARCH_CPUIDLE_HALTPOLL
826b1d40575SVitaly Kuznetsov	select X86_HV_CALLBACK_VECTOR
8276276a074SBorislav Petkov	default y
828a7f7f624SMasahiro Yamada	help
8296276a074SBorislav Petkov	  This option enables various optimizations for running under the KVM
8306276a074SBorislav Petkov	  hypervisor. It includes a paravirtualized clock, so that instead
8316276a074SBorislav Petkov	  of relying on a PIT (or probably other) emulation by the
8326276a074SBorislav Petkov	  underlying device model, the host provides the guest with
8336276a074SBorislav Petkov	  timing infrastructure such as time of day, and system time
8346276a074SBorislav Petkov
835a1c4423bSMarcelo Tosatticonfig ARCH_CPUIDLE_HALTPOLL
836a1c4423bSMarcelo Tosatti	def_bool n
837a1c4423bSMarcelo Tosatti	prompt "Disable host haltpoll when loading haltpoll driver"
838a1c4423bSMarcelo Tosatti	help
839a1c4423bSMarcelo Tosatti	  If virtualized under KVM, disable host haltpoll.
840a1c4423bSMarcelo Tosatti
8417733607fSMaran Wilsonconfig PVH
8427733607fSMaran Wilson	bool "Support for running PVH guests"
843a7f7f624SMasahiro Yamada	help
8447733607fSMaran Wilson	  This option enables the PVH entry point for guest virtual machines
8457733607fSMaran Wilson	  as specified in the x86/HVM direct boot ABI.
8467733607fSMaran Wilson
8476276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING
8486276a074SBorislav Petkov	bool "Paravirtual steal time accounting"
8496276a074SBorislav Petkov	depends on PARAVIRT
850a7f7f624SMasahiro Yamada	help
8516276a074SBorislav Petkov	  Select this option to enable fine granularity task steal time
8526276a074SBorislav Petkov	  accounting. Time spent executing other tasks in parallel with
8536276a074SBorislav Petkov	  the current vCPU is discounted from the vCPU power. To account for
8546276a074SBorislav Petkov	  that, there can be a small performance impact.
8556276a074SBorislav Petkov
8566276a074SBorislav Petkov	  If in doubt, say N here.
8576276a074SBorislav Petkov
8587af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK
8597af192c9SGerd Hoffmann	bool
8607af192c9SGerd Hoffmann
8614a362601SJan Kiszkaconfig JAILHOUSE_GUEST
8624a362601SJan Kiszka	bool "Jailhouse non-root cell support"
863abde587bSArnd Bergmann	depends on X86_64 && PCI
86487e65d05SJan Kiszka	select X86_PM_TIMER
865a7f7f624SMasahiro Yamada	help
8664a362601SJan Kiszka	  This option allows to run Linux as guest in a Jailhouse non-root
8674a362601SJan Kiszka	  cell. You can leave this option disabled if you only want to start
8684a362601SJan Kiszka	  Jailhouse and run Linux afterwards in the root cell.
8694a362601SJan Kiszka
870ec7972c9SZhao Yakuiconfig ACRN_GUEST
871ec7972c9SZhao Yakui	bool "ACRN Guest support"
872ec7972c9SZhao Yakui	depends on X86_64
873498ad393SZhao Yakui	select X86_HV_CALLBACK_VECTOR
874ec7972c9SZhao Yakui	help
875ec7972c9SZhao Yakui	  This option allows to run Linux as guest in the ACRN hypervisor. ACRN is
876ec7972c9SZhao Yakui	  a flexible, lightweight reference open-source hypervisor, built with
877ec7972c9SZhao Yakui	  real-time and safety-criticality in mind. It is built for embedded
878ec7972c9SZhao Yakui	  IOT with small footprint and real-time features. More details can be
879ec7972c9SZhao Yakui	  found in https://projectacrn.org/.
880ec7972c9SZhao Yakui
8816276a074SBorislav Petkovendif #HYPERVISOR_GUEST
88297349135SJeremy Fitzhardinge
883506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu"
884506f1d07SSam Ravnborg
885506f1d07SSam Ravnborgconfig HPET_TIMER
8863c2362e6SHarvey Harrison	def_bool X86_64
887506f1d07SSam Ravnborg	prompt "HPET Timer Support" if X86_32
888a7f7f624SMasahiro Yamada	help
889506f1d07SSam Ravnborg	  Use the IA-PC HPET (High Precision Event Timer) to manage
890506f1d07SSam Ravnborg	  time in preference to the PIT and RTC, if a HPET is
891506f1d07SSam Ravnborg	  present.
892506f1d07SSam Ravnborg	  HPET is the next generation timer replacing legacy 8254s.
893506f1d07SSam Ravnborg	  The HPET provides a stable time base on SMP
894506f1d07SSam Ravnborg	  systems, unlike the TSC, but it is more expensive to access,
8954e7f9df2SMichael S. Tsirkin	  as it is off-chip.  The interface used is documented
8964e7f9df2SMichael S. Tsirkin	  in the HPET spec, revision 1.
897506f1d07SSam Ravnborg
898506f1d07SSam Ravnborg	  You can safely choose Y here.  However, HPET will only be
899506f1d07SSam Ravnborg	  activated if the platform and the BIOS support this feature.
900506f1d07SSam Ravnborg	  Otherwise the 8254 will be used for timing services.
901506f1d07SSam Ravnborg
902506f1d07SSam Ravnborg	  Choose N to continue using the legacy 8254 timer.
903506f1d07SSam Ravnborg
904506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC
9053c2362e6SHarvey Harrison	def_bool y
9063228e1dcSAnand K Mistry	depends on HPET_TIMER && (RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
907506f1d07SSam Ravnborg
9086a108a14SDavid Rientjes# Mark as expert because too many people got it wrong.
909506f1d07SSam Ravnborg# The code disables itself when not needed.
9107ae9392cSThomas Petazzoniconfig DMI
9117ae9392cSThomas Petazzoni	default y
912cf074402SArd Biesheuvel	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
9136a108a14SDavid Rientjes	bool "Enable DMI scanning" if EXPERT
914a7f7f624SMasahiro Yamada	help
9157ae9392cSThomas Petazzoni	  Enabled scanning of DMI to identify machine quirks. Say Y
9167ae9392cSThomas Petazzoni	  here unless you have verified that your setup is not
9177ae9392cSThomas Petazzoni	  affected by entries in the DMI blacklist. Required by PNP
9187ae9392cSThomas Petazzoni	  BIOS code.
9197ae9392cSThomas Petazzoni
920506f1d07SSam Ravnborgconfig GART_IOMMU
92138901f1cSAndi Kleen	bool "Old AMD GART IOMMU support"
9222f9237d4SChristoph Hellwig	select DMA_OPS
923a4ce5a48SChristoph Hellwig	select IOMMU_HELPER
924506f1d07SSam Ravnborg	select SWIOTLB
92523ac4ae8SAndreas Herrmann	depends on X86_64 && PCI && AMD_NB
926a7f7f624SMasahiro Yamada	help
927ced3c42cSIngo Molnar	  Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
928ced3c42cSIngo Molnar	  GART based hardware IOMMUs.
929ced3c42cSIngo Molnar
930ced3c42cSIngo Molnar	  The GART supports full DMA access for devices with 32-bit access
931ced3c42cSIngo Molnar	  limitations, on systems with more than 3 GB. This is usually needed
932ced3c42cSIngo Molnar	  for USB, sound, many IDE/SATA chipsets and some other devices.
933ced3c42cSIngo Molnar
934ced3c42cSIngo Molnar	  Newer systems typically have a modern AMD IOMMU, supported via
935ced3c42cSIngo Molnar	  the CONFIG_AMD_IOMMU=y config option.
936ced3c42cSIngo Molnar
937ced3c42cSIngo Molnar	  In normal configurations this driver is only active when needed:
938ced3c42cSIngo Molnar	  there's more than 3 GB of memory and the system contains a
939ced3c42cSIngo Molnar	  32-bit limited device.
940ced3c42cSIngo Molnar
941ced3c42cSIngo Molnar	  If unsure, say Y.
942506f1d07SSam Ravnborg
9431184dc2fSMike Travisconfig MAXSMP
944ddb0c5a6SSamuel Thibault	bool "Enable Maximum number of SMP Processors and NUMA Nodes"
9456ea30386SKees Cook	depends on X86_64 && SMP && DEBUG_KERNEL
94636f5101aSMike Travis	select CPUMASK_OFFSTACK
947a7f7f624SMasahiro Yamada	help
948ddb0c5a6SSamuel Thibault	  Enable maximum number of CPUS and NUMA Nodes for this architecture.
9491184dc2fSMike Travis	  If unsure, say N.
950506f1d07SSam Ravnborg
951aec6487eSIngo Molnar#
952aec6487eSIngo Molnar# The maximum number of CPUs supported:
953aec6487eSIngo Molnar#
954aec6487eSIngo Molnar# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
955aec6487eSIngo Molnar# and which can be configured interactively in the
956aec6487eSIngo Molnar# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
957aec6487eSIngo Molnar#
958aec6487eSIngo Molnar# The ranges are different on 32-bit and 64-bit kernels, depending on
959aec6487eSIngo Molnar# hardware capabilities and scalability features of the kernel.
960aec6487eSIngo Molnar#
961aec6487eSIngo Molnar# ( If MAXSMP is enabled we just use the highest possible value and disable
962aec6487eSIngo Molnar#   interactive configuration. )
963aec6487eSIngo Molnar#
964a0d0bb4dSRandy Dunlap
965aec6487eSIngo Molnarconfig NR_CPUS_RANGE_BEGIN
966a0d0bb4dSRandy Dunlap	int
967aec6487eSIngo Molnar	default NR_CPUS_RANGE_END if MAXSMP
968a0d0bb4dSRandy Dunlap	default    1 if !SMP
969a0d0bb4dSRandy Dunlap	default    2
970a0d0bb4dSRandy Dunlap
971aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END
972a0d0bb4dSRandy Dunlap	int
973a0d0bb4dSRandy Dunlap	depends on X86_32
974aec6487eSIngo Molnar	default   64 if  SMP &&  X86_BIGSMP
975aec6487eSIngo Molnar	default    8 if  SMP && !X86_BIGSMP
976a0d0bb4dSRandy Dunlap	default    1 if !SMP
977a0d0bb4dSRandy Dunlap
978aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END
979a0d0bb4dSRandy Dunlap	int
980a0d0bb4dSRandy Dunlap	depends on X86_64
9811edae1aeSScott Wood	default 8192 if  SMP && CPUMASK_OFFSTACK
9821edae1aeSScott Wood	default  512 if  SMP && !CPUMASK_OFFSTACK
983a0d0bb4dSRandy Dunlap	default    1 if !SMP
984aec6487eSIngo Molnar
985aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT
986aec6487eSIngo Molnar	int
987aec6487eSIngo Molnar	depends on X86_32
988aec6487eSIngo Molnar	default   32 if  X86_BIGSMP
989aec6487eSIngo Molnar	default    8 if  SMP
990aec6487eSIngo Molnar	default    1 if !SMP
991aec6487eSIngo Molnar
992aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT
993aec6487eSIngo Molnar	int
994aec6487eSIngo Molnar	depends on X86_64
995a0d0bb4dSRandy Dunlap	default 8192 if  MAXSMP
996a0d0bb4dSRandy Dunlap	default   64 if  SMP
997aec6487eSIngo Molnar	default    1 if !SMP
998a0d0bb4dSRandy Dunlap
999506f1d07SSam Ravnborgconfig NR_CPUS
100036f5101aSMike Travis	int "Maximum number of CPUs" if SMP && !MAXSMP
1001aec6487eSIngo Molnar	range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
1002aec6487eSIngo Molnar	default NR_CPUS_DEFAULT
1003a7f7f624SMasahiro Yamada	help
1004506f1d07SSam Ravnborg	  This allows you to specify the maximum number of CPUs which this
1005bb61ccc7SJosh Boyer	  kernel will support.  If CPUMASK_OFFSTACK is enabled, the maximum
1006cad14bb9SKirill A. Shutemov	  supported value is 8192, otherwise the maximum value is 512.  The
1007506f1d07SSam Ravnborg	  minimum value which makes sense is 2.
1008506f1d07SSam Ravnborg
1009aec6487eSIngo Molnar	  This is purely to save memory: each supported CPU adds about 8KB
1010aec6487eSIngo Molnar	  to the kernel image.
1011506f1d07SSam Ravnborg
101266558b73STim Chenconfig SCHED_CLUSTER
101366558b73STim Chen	bool "Cluster scheduler support"
101466558b73STim Chen	depends on SMP
101566558b73STim Chen	default y
101666558b73STim Chen	help
101766558b73STim Chen	  Cluster scheduler support improves the CPU scheduler's decision
101866558b73STim Chen	  making when dealing with machines that have clusters of CPUs.
101966558b73STim Chen	  Cluster usually means a couple of CPUs which are placed closely
102066558b73STim Chen	  by sharing mid-level caches, last-level cache tags or internal
102166558b73STim Chen	  busses.
102266558b73STim Chen
1023506f1d07SSam Ravnborgconfig SCHED_SMT
1024dbe73364SThomas Gleixner	def_bool y if SMP
1025506f1d07SSam Ravnborg
1026506f1d07SSam Ravnborgconfig SCHED_MC
10273c2362e6SHarvey Harrison	def_bool y
10283c2362e6SHarvey Harrison	prompt "Multi-core scheduler support"
1029c8e56d20SBorislav Petkov	depends on SMP
1030a7f7f624SMasahiro Yamada	help
1031506f1d07SSam Ravnborg	  Multi-core scheduler support improves the CPU scheduler's decision
1032506f1d07SSam Ravnborg	  making when dealing with multi-core CPU chips at a cost of slightly
1033506f1d07SSam Ravnborg	  increased overhead in some places. If unsure say N here.
1034506f1d07SSam Ravnborg
1035de966cf4STim Chenconfig SCHED_MC_PRIO
1036de966cf4STim Chen	bool "CPU core priorities scheduler support"
10370a21fc12SIngo Molnar	depends on SCHED_MC && CPU_SUP_INTEL
10380a21fc12SIngo Molnar	select X86_INTEL_PSTATE
10390a21fc12SIngo Molnar	select CPU_FREQ
1040de966cf4STim Chen	default y
1041a7f7f624SMasahiro Yamada	help
1042de966cf4STim Chen	  Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1043de966cf4STim Chen	  core ordering determined at manufacturing time, which allows
1044de966cf4STim Chen	  certain cores to reach higher turbo frequencies (when running
1045de966cf4STim Chen	  single threaded workloads) than others.
1046de966cf4STim Chen
1047de966cf4STim Chen	  Enabling this kernel feature teaches the scheduler about
1048de966cf4STim Chen	  the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1049de966cf4STim Chen	  scheduler's CPU selection logic accordingly, so that higher
1050de966cf4STim Chen	  overall system performance can be achieved.
1051de966cf4STim Chen
1052de966cf4STim Chen	  This feature will have no effect on CPUs without this feature.
1053de966cf4STim Chen
1054de966cf4STim Chen	  If unsure say Y here.
10555e76b2abSTim Chen
105630b8b006SThomas Gleixnerconfig UP_LATE_INIT
105730b8b006SThomas Gleixner	def_bool y
1058ba360f88SThomas Gleixner	depends on !SMP && X86_LOCAL_APIC
105930b8b006SThomas Gleixner
1060506f1d07SSam Ravnborgconfig X86_UP_APIC
106150849eefSJan Beulich	bool "Local APIC support on uniprocessors" if !PCI_MSI
106250849eefSJan Beulich	default PCI_MSI
106338a1dfdaSBryan O'Donoghue	depends on X86_32 && !SMP && !X86_32_NON_STANDARD
1064a7f7f624SMasahiro Yamada	help
1065506f1d07SSam Ravnborg	  A local APIC (Advanced Programmable Interrupt Controller) is an
1066506f1d07SSam Ravnborg	  integrated interrupt controller in the CPU. If you have a single-CPU
1067506f1d07SSam Ravnborg	  system which has a processor with a local APIC, you can say Y here to
1068506f1d07SSam Ravnborg	  enable and use it. If you say Y here even though your machine doesn't
1069506f1d07SSam Ravnborg	  have a local APIC, then the kernel will still run with no slowdown at
1070506f1d07SSam Ravnborg	  all. The local APIC supports CPU-generated self-interrupts (timer,
1071506f1d07SSam Ravnborg	  performance counters), and the NMI watchdog which detects hard
1072506f1d07SSam Ravnborg	  lockups.
1073506f1d07SSam Ravnborg
1074506f1d07SSam Ravnborgconfig X86_UP_IOAPIC
1075506f1d07SSam Ravnborg	bool "IO-APIC support on uniprocessors"
1076506f1d07SSam Ravnborg	depends on X86_UP_APIC
1077a7f7f624SMasahiro Yamada	help
1078506f1d07SSam Ravnborg	  An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1079506f1d07SSam Ravnborg	  SMP-capable replacement for PC-style interrupt controllers. Most
1080506f1d07SSam Ravnborg	  SMP systems and many recent uniprocessor systems have one.
1081506f1d07SSam Ravnborg
1082506f1d07SSam Ravnborg	  If you have a single-CPU system with an IO-APIC, you can say Y here
1083506f1d07SSam Ravnborg	  to use it. If you say Y here even though your machine doesn't have
1084506f1d07SSam Ravnborg	  an IO-APIC, then the kernel will still run with no slowdown at all.
1085506f1d07SSam Ravnborg
1086506f1d07SSam Ravnborgconfig X86_LOCAL_APIC
10873c2362e6SHarvey Harrison	def_bool y
10880dbc6078SThomas Petazzoni	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
1089b5dc8e6cSJiang Liu	select IRQ_DOMAIN_HIERARCHY
109052f518a3SJiang Liu	select PCI_MSI_IRQ_DOMAIN if PCI_MSI
1091506f1d07SSam Ravnborg
1092506f1d07SSam Ravnborgconfig X86_IO_APIC
1093b1da1e71SJan Beulich	def_bool y
1094b1da1e71SJan Beulich	depends on X86_LOCAL_APIC || X86_UP_IOAPIC
1095506f1d07SSam Ravnborg
109641b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS
109741b9eb26SStefan Assmann	bool "Reroute for broken boot IRQs"
109841b9eb26SStefan Assmann	depends on X86_IO_APIC
1099a7f7f624SMasahiro Yamada	help
110041b9eb26SStefan Assmann	  This option enables a workaround that fixes a source of
110141b9eb26SStefan Assmann	  spurious interrupts. This is recommended when threaded
110241b9eb26SStefan Assmann	  interrupt handling is used on systems where the generation of
110341b9eb26SStefan Assmann	  superfluous "boot interrupts" cannot be disabled.
110441b9eb26SStefan Assmann
110541b9eb26SStefan Assmann	  Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
110641b9eb26SStefan Assmann	  entry in the chipset's IO-APIC is masked (as, e.g. the RT
110741b9eb26SStefan Assmann	  kernel does during interrupt handling). On chipsets where this
110841b9eb26SStefan Assmann	  boot IRQ generation cannot be disabled, this workaround keeps
110941b9eb26SStefan Assmann	  the original IRQ line masked so that only the equivalent "boot
111041b9eb26SStefan Assmann	  IRQ" is delivered to the CPUs. The workaround also tells the
111141b9eb26SStefan Assmann	  kernel to set up the IRQ handler on the boot IRQ line. In this
111241b9eb26SStefan Assmann	  way only one interrupt is delivered to the kernel. Otherwise
111341b9eb26SStefan Assmann	  the spurious second interrupt may cause the kernel to bring
111441b9eb26SStefan Assmann	  down (vital) interrupt lines.
111541b9eb26SStefan Assmann
111641b9eb26SStefan Assmann	  Only affects "broken" chipsets. Interrupt sharing may be
111741b9eb26SStefan Assmann	  increased on these systems.
111841b9eb26SStefan Assmann
1119506f1d07SSam Ravnborgconfig X86_MCE
1120bab9bc65SAndi Kleen	bool "Machine Check / overheating reporting"
1121648ed940SChen, Gong	select GENERIC_ALLOCATOR
1122e57dbaf7SBorislav Petkov	default y
1123a7f7f624SMasahiro Yamada	help
1124bab9bc65SAndi Kleen	  Machine Check support allows the processor to notify the
1125bab9bc65SAndi Kleen	  kernel if it detects a problem (e.g. overheating, data corruption).
1126506f1d07SSam Ravnborg	  The action the kernel takes depends on the severity of the problem,
1127bab9bc65SAndi Kleen	  ranging from warning messages to halting the machine.
11284efc0670SAndi Kleen
11295de97c9fSTony Luckconfig X86_MCELOG_LEGACY
11305de97c9fSTony Luck	bool "Support for deprecated /dev/mcelog character device"
11315de97c9fSTony Luck	depends on X86_MCE
1132a7f7f624SMasahiro Yamada	help
11335de97c9fSTony Luck	  Enable support for /dev/mcelog which is needed by the old mcelog
11345de97c9fSTony Luck	  userspace logging daemon. Consider switching to the new generation
11355de97c9fSTony Luck	  rasdaemon solution.
11365de97c9fSTony Luck
1137506f1d07SSam Ravnborgconfig X86_MCE_INTEL
11383c2362e6SHarvey Harrison	def_bool y
11393c2362e6SHarvey Harrison	prompt "Intel MCE features"
1140c1ebf835SAndi Kleen	depends on X86_MCE && X86_LOCAL_APIC
1141a7f7f624SMasahiro Yamada	help
1142506f1d07SSam Ravnborg	   Additional support for intel specific MCE features such as
1143506f1d07SSam Ravnborg	   the thermal monitor.
1144506f1d07SSam Ravnborg
1145506f1d07SSam Ravnborgconfig X86_MCE_AMD
11463c2362e6SHarvey Harrison	def_bool y
11473c2362e6SHarvey Harrison	prompt "AMD MCE features"
1148f5382de9SYazen Ghannam	depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
1149a7f7f624SMasahiro Yamada	help
1150506f1d07SSam Ravnborg	   Additional support for AMD specific MCE features such as
1151506f1d07SSam Ravnborg	   the DRAM Error Threshold.
1152506f1d07SSam Ravnborg
11534efc0670SAndi Kleenconfig X86_ANCIENT_MCE
11546fc108a0SJan Beulich	bool "Support for old Pentium 5 / WinChip machine checks"
1155c31d9633SAndi Kleen	depends on X86_32 && X86_MCE
1156a7f7f624SMasahiro Yamada	help
11574efc0670SAndi Kleen	  Include support for machine check handling on old Pentium 5 or WinChip
11585065a706SMasanari Iida	  systems. These typically need to be enabled explicitly on the command
11594efc0670SAndi Kleen	  line.
11604efc0670SAndi Kleen
1161b2762686SAndi Kleenconfig X86_MCE_THRESHOLD
1162b2762686SAndi Kleen	depends on X86_MCE_AMD || X86_MCE_INTEL
11636fc108a0SJan Beulich	def_bool y
1164b2762686SAndi Kleen
1165ea149b36SAndi Kleenconfig X86_MCE_INJECT
1166bc8e80d5SBorislav Petkov	depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
1167ea149b36SAndi Kleen	tristate "Machine check injector support"
1168a7f7f624SMasahiro Yamada	help
1169ea149b36SAndi Kleen	  Provide support for injecting machine checks for testing purposes.
1170ea149b36SAndi Kleen	  If you don't know what a machine check is and you don't do kernel
1171ea149b36SAndi Kleen	  QA it is safe to say n.
1172ea149b36SAndi Kleen
117307dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig"
1174e633c65aSKan Liang
11755aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86
11761e642812SIngo Molnar	bool "Legacy VM86 support"
1177506f1d07SSam Ravnborg	depends on X86_32
1178a7f7f624SMasahiro Yamada	help
11795aef51c3SAndy Lutomirski	  This option allows user programs to put the CPU into V8086
11805aef51c3SAndy Lutomirski	  mode, which is an 80286-era approximation of 16-bit real mode.
11815aef51c3SAndy Lutomirski
11825aef51c3SAndy Lutomirski	  Some very old versions of X and/or vbetool require this option
11835aef51c3SAndy Lutomirski	  for user mode setting.  Similarly, DOSEMU will use it if
11845aef51c3SAndy Lutomirski	  available to accelerate real mode DOS programs.  However, any
11855aef51c3SAndy Lutomirski	  recent version of DOSEMU, X, or vbetool should be fully
11865aef51c3SAndy Lutomirski	  functional even without kernel VM86 support, as they will all
11871e642812SIngo Molnar	  fall back to software emulation. Nevertheless, if you are using
11881e642812SIngo Molnar	  a 16-bit DOS program where 16-bit performance matters, vm86
11891e642812SIngo Molnar	  mode might be faster than emulation and you might want to
11901e642812SIngo Molnar	  enable this option.
11915aef51c3SAndy Lutomirski
11921e642812SIngo Molnar	  Note that any app that works on a 64-bit kernel is unlikely to
11931e642812SIngo Molnar	  need this option, as 64-bit kernels don't, and can't, support
11941e642812SIngo Molnar	  V8086 mode. This option is also unrelated to 16-bit protected
11951e642812SIngo Molnar	  mode and is not needed to run most 16-bit programs under Wine.
11965aef51c3SAndy Lutomirski
11971e642812SIngo Molnar	  Enabling this option increases the complexity of the kernel
11981e642812SIngo Molnar	  and slows down exception handling a tiny bit.
11995aef51c3SAndy Lutomirski
12001e642812SIngo Molnar	  If unsure, say N here.
12015aef51c3SAndy Lutomirski
12025aef51c3SAndy Lutomirskiconfig VM86
12035aef51c3SAndy Lutomirski	bool
12045aef51c3SAndy Lutomirski	default X86_LEGACY_VM86
120534273f41SH. Peter Anvin
120634273f41SH. Peter Anvinconfig X86_16BIT
120734273f41SH. Peter Anvin	bool "Enable support for 16-bit segments" if EXPERT
120834273f41SH. Peter Anvin	default y
1209a5b9e5a2SAndy Lutomirski	depends on MODIFY_LDT_SYSCALL
1210a7f7f624SMasahiro Yamada	help
121134273f41SH. Peter Anvin	  This option is required by programs like Wine to run 16-bit
121234273f41SH. Peter Anvin	  protected mode legacy code on x86 processors.  Disabling
121334273f41SH. Peter Anvin	  this option saves about 300 bytes on i386, or around 6K text
121434273f41SH. Peter Anvin	  plus 16K runtime memory on x86-64,
121534273f41SH. Peter Anvin
121634273f41SH. Peter Anvinconfig X86_ESPFIX32
121734273f41SH. Peter Anvin	def_bool y
121834273f41SH. Peter Anvin	depends on X86_16BIT && X86_32
1219506f1d07SSam Ravnborg
1220197725deSH. Peter Anvinconfig X86_ESPFIX64
1221197725deSH. Peter Anvin	def_bool y
122234273f41SH. Peter Anvin	depends on X86_16BIT && X86_64
1223506f1d07SSam Ravnborg
12241ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION
12251ad83c85SAndy Lutomirski	bool "Enable vsyscall emulation" if EXPERT
12261ad83c85SAndy Lutomirski	default y
12271ad83c85SAndy Lutomirski	depends on X86_64
1228a7f7f624SMasahiro Yamada	help
12291ad83c85SAndy Lutomirski	 This enables emulation of the legacy vsyscall page.  Disabling
12301ad83c85SAndy Lutomirski	 it is roughly equivalent to booting with vsyscall=none, except
12311ad83c85SAndy Lutomirski	 that it will also disable the helpful warning if a program
12321ad83c85SAndy Lutomirski	 tries to use a vsyscall.  With this option set to N, offending
12331ad83c85SAndy Lutomirski	 programs will just segfault, citing addresses of the form
12341ad83c85SAndy Lutomirski	 0xffffffffff600?00.
12351ad83c85SAndy Lutomirski
12361ad83c85SAndy Lutomirski	 This option is required by many programs built before 2013, and
12371ad83c85SAndy Lutomirski	 care should be used even with newer programs if set to N.
12381ad83c85SAndy Lutomirski
12391ad83c85SAndy Lutomirski	 Disabling this option saves about 7K of kernel size and
12401ad83c85SAndy Lutomirski	 possibly 4K of additional runtime pagetable memory.
12411ad83c85SAndy Lutomirski
1242111e7b15SThomas Gleixnerconfig X86_IOPL_IOPERM
1243111e7b15SThomas Gleixner	bool "IOPERM and IOPL Emulation"
1244a24ca997SThomas Gleixner	default y
1245a7f7f624SMasahiro Yamada	help
1246111e7b15SThomas Gleixner	  This enables the ioperm() and iopl() syscalls which are necessary
1247111e7b15SThomas Gleixner	  for legacy applications.
1248111e7b15SThomas Gleixner
1249c8137aceSThomas Gleixner	  Legacy IOPL support is an overbroad mechanism which allows user
1250c8137aceSThomas Gleixner	  space aside of accessing all 65536 I/O ports also to disable
1251c8137aceSThomas Gleixner	  interrupts. To gain this access the caller needs CAP_SYS_RAWIO
1252c8137aceSThomas Gleixner	  capabilities and permission from potentially active security
1253c8137aceSThomas Gleixner	  modules.
1254c8137aceSThomas Gleixner
1255c8137aceSThomas Gleixner	  The emulation restricts the functionality of the syscall to
1256c8137aceSThomas Gleixner	  only allowing the full range I/O port access, but prevents the
1257a24ca997SThomas Gleixner	  ability to disable interrupts from user space which would be
1258a24ca997SThomas Gleixner	  granted if the hardware IOPL mechanism would be used.
1259c8137aceSThomas Gleixner
1260506f1d07SSam Ravnborgconfig TOSHIBA
1261506f1d07SSam Ravnborg	tristate "Toshiba Laptop support"
1262506f1d07SSam Ravnborg	depends on X86_32
1263a7f7f624SMasahiro Yamada	help
1264506f1d07SSam Ravnborg	  This adds a driver to safely access the System Management Mode of
1265506f1d07SSam Ravnborg	  the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1266506f1d07SSam Ravnborg	  not work on models with a Phoenix BIOS. The System Management Mode
1267506f1d07SSam Ravnborg	  is used to set the BIOS and power saving options on Toshiba portables.
1268506f1d07SSam Ravnborg
1269506f1d07SSam Ravnborg	  For information on utilities to make use of this driver see the
1270506f1d07SSam Ravnborg	  Toshiba Linux utilities web site at:
1271506f1d07SSam Ravnborg	  <http://www.buzzard.org.uk/toshiba/>.
1272506f1d07SSam Ravnborg
1273506f1d07SSam Ravnborg	  Say Y if you intend to run this kernel on a Toshiba portable.
1274506f1d07SSam Ravnborg	  Say N otherwise.
1275506f1d07SSam Ravnborg
1276506f1d07SSam Ravnborgconfig I8K
1277039ae585SPali Rohár	tristate "Dell i8k legacy laptop support"
1278ef775a0eSRandy Dunlap	depends on HWMON
1279ef775a0eSRandy Dunlap	depends on PROC_FS
1280039ae585SPali Rohár	select SENSORS_DELL_SMM
1281a7f7f624SMasahiro Yamada	help
1282039ae585SPali Rohár	  This option enables legacy /proc/i8k userspace interface in hwmon
1283039ae585SPali Rohár	  dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1284039ae585SPali Rohár	  temperature and allows controlling fan speeds of Dell laptops via
1285039ae585SPali Rohár	  System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1286039ae585SPali Rohár	  it reports also power and hotkey status. For fan speed control is
1287039ae585SPali Rohár	  needed userspace package i8kutils.
1288506f1d07SSam Ravnborg
1289039ae585SPali Rohár	  Say Y if you intend to run this kernel on old Dell laptops or want to
1290039ae585SPali Rohár	  use userspace package i8kutils.
1291506f1d07SSam Ravnborg	  Say N otherwise.
1292506f1d07SSam Ravnborg
1293506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS
12949ba16087SJan Beulich	bool "Enable X86 board specific fixups for reboot"
12959ba16087SJan Beulich	depends on X86_32
1296a7f7f624SMasahiro Yamada	help
1297506f1d07SSam Ravnborg	  This enables chipset and/or board specific fixups to be done
1298506f1d07SSam Ravnborg	  in order to get reboot to work correctly. This is only needed on
1299506f1d07SSam Ravnborg	  some combinations of hardware and BIOS. The symptom, for which
1300506f1d07SSam Ravnborg	  this config is intended, is when reboot ends with a stalled/hung
1301506f1d07SSam Ravnborg	  system.
1302506f1d07SSam Ravnborg
1303506f1d07SSam Ravnborg	  Currently, the only fixup is for the Geode machines using
13045e3a77e9SFlorian Fainelli	  CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1305506f1d07SSam Ravnborg
1306506f1d07SSam Ravnborg	  Say Y if you want to enable the fixup. Currently, it's safe to
1307506f1d07SSam Ravnborg	  enable this option even if you don't need it.
1308506f1d07SSam Ravnborg	  Say N otherwise.
1309506f1d07SSam Ravnborg
1310506f1d07SSam Ravnborgconfig MICROCODE
13119a2bc335SBorislav Petkov	bool "CPU microcode loading support"
13129a2bc335SBorislav Petkov	default y
131380030e3dSBorislav Petkov	depends on CPU_SUP_AMD || CPU_SUP_INTEL
1314a7f7f624SMasahiro Yamada	help
1315506f1d07SSam Ravnborg	  If you say Y here, you will be able to update the microcode on
13165f9c01aaSBorislav Petkov	  Intel and AMD processors. The Intel support is for the IA32 family,
13175f9c01aaSBorislav Petkov	  e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
13185f9c01aaSBorislav Petkov	  AMD support is for families 0x10 and later. You will obviously need
13195f9c01aaSBorislav Petkov	  the actual microcode binary data itself which is not shipped with
13205f9c01aaSBorislav Petkov	  the Linux kernel.
1321506f1d07SSam Ravnborg
13225f9c01aaSBorislav Petkov	  The preferred method to load microcode from a detached initrd is described
1323cb1aaebeSMauro Carvalho Chehab	  in Documentation/x86/microcode.rst. For that you need to enable
13245f9c01aaSBorislav Petkov	  CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
13255f9c01aaSBorislav Petkov	  initrd for microcode blobs.
1326506f1d07SSam Ravnborg
1327c508c46eSBenjamin Gilbert	  In addition, you can build the microcode into the kernel. For that you
1328c508c46eSBenjamin Gilbert	  need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1329c508c46eSBenjamin Gilbert	  config option.
1330506f1d07SSam Ravnborg
13318d86f390SPeter Orubaconfig MICROCODE_INTEL
1332e43f6e67SBorislav Petkov	bool "Intel microcode loading support"
13338d86f390SPeter Oruba	depends on MICROCODE
13348d86f390SPeter Oruba	default MICROCODE
1335a7f7f624SMasahiro Yamada	help
13368d86f390SPeter Oruba	  This options enables microcode patch loading support for Intel
13378d86f390SPeter Oruba	  processors.
13388d86f390SPeter Oruba
1339b8989db9SAlan	  For the current Intel microcode data package go to
1340b8989db9SAlan	  <https://downloadcenter.intel.com> and search for
1341b8989db9SAlan	  'Linux Processor Microcode Data File'.
13428d86f390SPeter Oruba
134380cc9f10SPeter Orubaconfig MICROCODE_AMD
1344e43f6e67SBorislav Petkov	bool "AMD microcode loading support"
134580cc9f10SPeter Oruba	depends on MICROCODE
1346a7f7f624SMasahiro Yamada	help
134780cc9f10SPeter Oruba	  If you select this option, microcode patch loading support for AMD
134880cc9f10SPeter Oruba	  processors will be enabled.
134980cc9f10SPeter Oruba
1350506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE
1351c02f48e0SBorislav Petkov	bool "Ancient loading interface (DEPRECATED)"
1352c02f48e0SBorislav Petkov	default n
1353506f1d07SSam Ravnborg	depends on MICROCODE
1354a7f7f624SMasahiro Yamada	help
1355c02f48e0SBorislav Petkov	  DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface
1356c02f48e0SBorislav Petkov	  which was used by userspace tools like iucode_tool and microcode.ctl.
1357c02f48e0SBorislav Petkov	  It is inadequate because it runs too late to be able to properly
1358c02f48e0SBorislav Petkov	  load microcode on a machine and it needs special tools. Instead, you
1359c02f48e0SBorislav Petkov	  should've switched to the early loading method with the initrd or
1360cb1aaebeSMauro Carvalho Chehab	  builtin microcode by now: Documentation/x86/microcode.rst
1361506f1d07SSam Ravnborg
1362506f1d07SSam Ravnborgconfig X86_MSR
1363506f1d07SSam Ravnborg	tristate "/dev/cpu/*/msr - Model-specific register support"
1364a7f7f624SMasahiro Yamada	help
1365506f1d07SSam Ravnborg	  This device gives privileged processes access to the x86
1366506f1d07SSam Ravnborg	  Model-Specific Registers (MSRs).  It is a character device with
1367506f1d07SSam Ravnborg	  major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1368506f1d07SSam Ravnborg	  MSR accesses are directed to a specific CPU on multi-processor
1369506f1d07SSam Ravnborg	  systems.
1370506f1d07SSam Ravnborg
1371506f1d07SSam Ravnborgconfig X86_CPUID
1372506f1d07SSam Ravnborg	tristate "/dev/cpu/*/cpuid - CPU information support"
1373a7f7f624SMasahiro Yamada	help
1374506f1d07SSam Ravnborg	  This device gives processes access to the x86 CPUID instruction to
1375506f1d07SSam Ravnborg	  be executed on a specific processor.  It is a character device
1376506f1d07SSam Ravnborg	  with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1377506f1d07SSam Ravnborg	  /dev/cpu/31/cpuid.
1378506f1d07SSam Ravnborg
1379506f1d07SSam Ravnborgchoice
1380506f1d07SSam Ravnborg	prompt "High Memory Support"
13816fc108a0SJan Beulich	default HIGHMEM4G
1382506f1d07SSam Ravnborg	depends on X86_32
1383506f1d07SSam Ravnborg
1384506f1d07SSam Ravnborgconfig NOHIGHMEM
1385506f1d07SSam Ravnborg	bool "off"
1386a7f7f624SMasahiro Yamada	help
1387506f1d07SSam Ravnborg	  Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1388506f1d07SSam Ravnborg	  However, the address space of 32-bit x86 processors is only 4
1389506f1d07SSam Ravnborg	  Gigabytes large. That means that, if you have a large amount of
1390506f1d07SSam Ravnborg	  physical memory, not all of it can be "permanently mapped" by the
1391506f1d07SSam Ravnborg	  kernel. The physical memory that's not permanently mapped is called
1392506f1d07SSam Ravnborg	  "high memory".
1393506f1d07SSam Ravnborg
1394506f1d07SSam Ravnborg	  If you are compiling a kernel which will never run on a machine with
1395506f1d07SSam Ravnborg	  more than 1 Gigabyte total physical RAM, answer "off" here (default
1396506f1d07SSam Ravnborg	  choice and suitable for most users). This will result in a "3GB/1GB"
1397506f1d07SSam Ravnborg	  split: 3GB are mapped so that each process sees a 3GB virtual memory
1398506f1d07SSam Ravnborg	  space and the remaining part of the 4GB virtual memory space is used
1399506f1d07SSam Ravnborg	  by the kernel to permanently map as much physical memory as
1400506f1d07SSam Ravnborg	  possible.
1401506f1d07SSam Ravnborg
1402506f1d07SSam Ravnborg	  If the machine has between 1 and 4 Gigabytes physical RAM, then
1403506f1d07SSam Ravnborg	  answer "4GB" here.
1404506f1d07SSam Ravnborg
1405506f1d07SSam Ravnborg	  If more than 4 Gigabytes is used then answer "64GB" here. This
1406506f1d07SSam Ravnborg	  selection turns Intel PAE (Physical Address Extension) mode on.
1407506f1d07SSam Ravnborg	  PAE implements 3-level paging on IA32 processors. PAE is fully
1408506f1d07SSam Ravnborg	  supported by Linux, PAE mode is implemented on all recent Intel
1409506f1d07SSam Ravnborg	  processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1410506f1d07SSam Ravnborg	  then the kernel will not boot on CPUs that don't support PAE!
1411506f1d07SSam Ravnborg
1412506f1d07SSam Ravnborg	  The actual amount of total physical memory will either be
1413506f1d07SSam Ravnborg	  auto detected or can be forced by using a kernel command line option
1414506f1d07SSam Ravnborg	  such as "mem=256M". (Try "man bootparam" or see the documentation of
1415506f1d07SSam Ravnborg	  your boot loader (lilo or loadlin) about how to pass options to the
1416506f1d07SSam Ravnborg	  kernel at boot time.)
1417506f1d07SSam Ravnborg
1418506f1d07SSam Ravnborg	  If unsure, say "off".
1419506f1d07SSam Ravnborg
1420506f1d07SSam Ravnborgconfig HIGHMEM4G
1421506f1d07SSam Ravnborg	bool "4GB"
1422a7f7f624SMasahiro Yamada	help
1423506f1d07SSam Ravnborg	  Select this if you have a 32-bit processor and between 1 and 4
1424506f1d07SSam Ravnborg	  gigabytes of physical RAM.
1425506f1d07SSam Ravnborg
1426506f1d07SSam Ravnborgconfig HIGHMEM64G
1427506f1d07SSam Ravnborg	bool "64GB"
1428225bac2dSLukas Bulwahn	depends on !M486SX && !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !MWINCHIP3D && !MK6
1429506f1d07SSam Ravnborg	select X86_PAE
1430a7f7f624SMasahiro Yamada	help
1431506f1d07SSam Ravnborg	  Select this if you have a 32-bit processor and more than 4
1432506f1d07SSam Ravnborg	  gigabytes of physical RAM.
1433506f1d07SSam Ravnborg
1434506f1d07SSam Ravnborgendchoice
1435506f1d07SSam Ravnborg
1436506f1d07SSam Ravnborgchoice
14376a108a14SDavid Rientjes	prompt "Memory split" if EXPERT
1438506f1d07SSam Ravnborg	default VMSPLIT_3G
1439506f1d07SSam Ravnborg	depends on X86_32
1440a7f7f624SMasahiro Yamada	help
1441506f1d07SSam Ravnborg	  Select the desired split between kernel and user memory.
1442506f1d07SSam Ravnborg
1443506f1d07SSam Ravnborg	  If the address range available to the kernel is less than the
1444506f1d07SSam Ravnborg	  physical memory installed, the remaining memory will be available
1445506f1d07SSam Ravnborg	  as "high memory". Accessing high memory is a little more costly
1446506f1d07SSam Ravnborg	  than low memory, as it needs to be mapped into the kernel first.
1447506f1d07SSam Ravnborg	  Note that increasing the kernel address space limits the range
1448506f1d07SSam Ravnborg	  available to user programs, making the address space there
1449506f1d07SSam Ravnborg	  tighter.  Selecting anything other than the default 3G/1G split
1450506f1d07SSam Ravnborg	  will also likely make your kernel incompatible with binary-only
1451506f1d07SSam Ravnborg	  kernel modules.
1452506f1d07SSam Ravnborg
1453506f1d07SSam Ravnborg	  If you are not absolutely sure what you are doing, leave this
1454506f1d07SSam Ravnborg	  option alone!
1455506f1d07SSam Ravnborg
1456506f1d07SSam Ravnborg	config VMSPLIT_3G
1457506f1d07SSam Ravnborg		bool "3G/1G user/kernel split"
1458506f1d07SSam Ravnborg	config VMSPLIT_3G_OPT
1459506f1d07SSam Ravnborg		depends on !X86_PAE
1460506f1d07SSam Ravnborg		bool "3G/1G user/kernel split (for full 1G low memory)"
1461506f1d07SSam Ravnborg	config VMSPLIT_2G
1462506f1d07SSam Ravnborg		bool "2G/2G user/kernel split"
1463506f1d07SSam Ravnborg	config VMSPLIT_2G_OPT
1464506f1d07SSam Ravnborg		depends on !X86_PAE
1465506f1d07SSam Ravnborg		bool "2G/2G user/kernel split (for full 2G low memory)"
1466506f1d07SSam Ravnborg	config VMSPLIT_1G
1467506f1d07SSam Ravnborg		bool "1G/3G user/kernel split"
1468506f1d07SSam Ravnborgendchoice
1469506f1d07SSam Ravnborg
1470506f1d07SSam Ravnborgconfig PAGE_OFFSET
1471506f1d07SSam Ravnborg	hex
1472506f1d07SSam Ravnborg	default 0xB0000000 if VMSPLIT_3G_OPT
1473506f1d07SSam Ravnborg	default 0x80000000 if VMSPLIT_2G
1474506f1d07SSam Ravnborg	default 0x78000000 if VMSPLIT_2G_OPT
1475506f1d07SSam Ravnborg	default 0x40000000 if VMSPLIT_1G
1476506f1d07SSam Ravnborg	default 0xC0000000
1477506f1d07SSam Ravnborg	depends on X86_32
1478506f1d07SSam Ravnborg
1479506f1d07SSam Ravnborgconfig HIGHMEM
14803c2362e6SHarvey Harrison	def_bool y
1481506f1d07SSam Ravnborg	depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1482506f1d07SSam Ravnborg
1483506f1d07SSam Ravnborgconfig X86_PAE
14849ba16087SJan Beulich	bool "PAE (Physical Address Extension) Support"
1485506f1d07SSam Ravnborg	depends on X86_32 && !HIGHMEM4G
1486d4a451d5SChristoph Hellwig	select PHYS_ADDR_T_64BIT
14879d99c712SChristian Melki	select SWIOTLB
1488a7f7f624SMasahiro Yamada	help
1489506f1d07SSam Ravnborg	  PAE is required for NX support, and furthermore enables
1490506f1d07SSam Ravnborg	  larger swapspace support for non-overcommit purposes. It
1491506f1d07SSam Ravnborg	  has the cost of more pagetable lookup overhead, and also
1492506f1d07SSam Ravnborg	  consumes more pagetable space per process.
1493506f1d07SSam Ravnborg
149477ef56e4SKirill A. Shutemovconfig X86_5LEVEL
149577ef56e4SKirill A. Shutemov	bool "Enable 5-level page tables support"
149618ec1eafSKirill A. Shutemov	default y
1497eedb92abSKirill A. Shutemov	select DYNAMIC_MEMORY_LAYOUT
1498162434e7SKirill A. Shutemov	select SPARSEMEM_VMEMMAP
149977ef56e4SKirill A. Shutemov	depends on X86_64
1500a7f7f624SMasahiro Yamada	help
150177ef56e4SKirill A. Shutemov	  5-level paging enables access to larger address space:
150277ef56e4SKirill A. Shutemov	  upto 128 PiB of virtual address space and 4 PiB of
150377ef56e4SKirill A. Shutemov	  physical address space.
150477ef56e4SKirill A. Shutemov
150577ef56e4SKirill A. Shutemov	  It will be supported by future Intel CPUs.
150677ef56e4SKirill A. Shutemov
15076657fca0SKirill A. Shutemov	  A kernel with the option enabled can be booted on machines that
15086657fca0SKirill A. Shutemov	  support 4- or 5-level paging.
150977ef56e4SKirill A. Shutemov
1510cb1aaebeSMauro Carvalho Chehab	  See Documentation/x86/x86_64/5level-paging.rst for more
151177ef56e4SKirill A. Shutemov	  information.
151277ef56e4SKirill A. Shutemov
151377ef56e4SKirill A. Shutemov	  Say N if unsure.
151477ef56e4SKirill A. Shutemov
151510971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES
1516e5008abeSLuis R. Rodriguez	def_bool y
15172e1da13fSVlastimil Babka	depends on X86_64
1518a7f7f624SMasahiro Yamada	help
151910971ab2SIngo Molnar	  Certain kernel features effectively disable kernel
152010971ab2SIngo Molnar	  linear 1 GB mappings (even if the CPU otherwise
152110971ab2SIngo Molnar	  supports them), so don't confuse the user by printing
152210971ab2SIngo Molnar	  that we have them enabled.
15239e899816SNick Piggin
15245c280cf6SThomas Gleixnerconfig X86_CPA_STATISTICS
15255c280cf6SThomas Gleixner	bool "Enable statistic for Change Page Attribute"
15265c280cf6SThomas Gleixner	depends on DEBUG_FS
1527a7f7f624SMasahiro Yamada	help
1528b75baaf3SIngo Molnar	  Expose statistics about the Change Page Attribute mechanism, which
1529a943245aSColin Ian King	  helps to determine the effectiveness of preserving large and huge
15305c280cf6SThomas Gleixner	  page mappings when mapping protections are changed.
15315c280cf6SThomas Gleixner
153220f07a04SKirill A. Shutemovconfig X86_MEM_ENCRYPT
153320f07a04SKirill A. Shutemov	select ARCH_HAS_FORCE_DMA_UNENCRYPTED
153420f07a04SKirill A. Shutemov	select DYNAMIC_PHYSICAL_MASK
153520f07a04SKirill A. Shutemov	select ARCH_HAS_RESTRICTED_VIRTIO_MEMORY_ACCESS
153620f07a04SKirill A. Shutemov	def_bool n
153720f07a04SKirill A. Shutemov
15387744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT
15397744ccdbSTom Lendacky	bool "AMD Secure Memory Encryption (SME) support"
15407744ccdbSTom Lendacky	depends on X86_64 && CPU_SUP_AMD
154182fef0adSDavid Rientjes	select DMA_COHERENT_POOL
1542ce9084baSArd Biesheuvel	select ARCH_USE_MEMREMAP_PROT
1543597cfe48SJoerg Roedel	select INSTRUCTION_DECODER
1544aa5a4611STom Lendacky	select ARCH_HAS_CC_PLATFORM
154520f07a04SKirill A. Shutemov	select X86_MEM_ENCRYPT
1546a7f7f624SMasahiro Yamada	help
15477744ccdbSTom Lendacky	  Say yes to enable support for the encryption of system memory.
15487744ccdbSTom Lendacky	  This requires an AMD processor that supports Secure Memory
15497744ccdbSTom Lendacky	  Encryption (SME).
15507744ccdbSTom Lendacky
15517744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
15527744ccdbSTom Lendacky	bool "Activate AMD Secure Memory Encryption (SME) by default"
15537744ccdbSTom Lendacky	depends on AMD_MEM_ENCRYPT
1554a7f7f624SMasahiro Yamada	help
15557744ccdbSTom Lendacky	  Say yes to have system memory encrypted by default if running on
15567744ccdbSTom Lendacky	  an AMD processor that supports Secure Memory Encryption (SME).
15577744ccdbSTom Lendacky
15587744ccdbSTom Lendacky	  If set to Y, then the encryption of system memory can be
15597744ccdbSTom Lendacky	  deactivated with the mem_encrypt=off command line option.
15607744ccdbSTom Lendacky
15617744ccdbSTom Lendacky	  If set to N, then the encryption of system memory can be
15627744ccdbSTom Lendacky	  activated with the mem_encrypt=on command line option.
15637744ccdbSTom Lendacky
1564506f1d07SSam Ravnborg# Common NUMA Features
1565506f1d07SSam Ravnborgconfig NUMA
1566e133f6eaSRandy Dunlap	bool "NUMA Memory Allocation and Scheduler Support"
1567506f1d07SSam Ravnborg	depends on SMP
1568b5660ba7SH. Peter Anvin	depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1569b5660ba7SH. Peter Anvin	default y if X86_BIGSMP
15707ecd19cfSKefeng Wang	select USE_PERCPU_NUMA_NODE_ID
1571a7f7f624SMasahiro Yamada	help
1572e133f6eaSRandy Dunlap	  Enable NUMA (Non-Uniform Memory Access) support.
1573fd51b2d7SKOSAKI Motohiro
1574506f1d07SSam Ravnborg	  The kernel will try to allocate memory used by a CPU on the
1575506f1d07SSam Ravnborg	  local memory controller of the CPU and add some more
1576506f1d07SSam Ravnborg	  NUMA awareness to the kernel.
1577506f1d07SSam Ravnborg
1578c280ea5eSIngo Molnar	  For 64-bit this is recommended if the system is Intel Core i7
1579fd51b2d7SKOSAKI Motohiro	  (or later), AMD Opteron, or EM64T NUMA.
1580fd51b2d7SKOSAKI Motohiro
1581b5660ba7SH. Peter Anvin	  For 32-bit this is only needed if you boot a 32-bit
15827cf6c945SDavid Rientjes	  kernel on a 64-bit NUMA platform.
1583fd51b2d7SKOSAKI Motohiro
1584fd51b2d7SKOSAKI Motohiro	  Otherwise, you should say N.
1585506f1d07SSam Ravnborg
1586eec1d4faSHans Rosenfeldconfig AMD_NUMA
15873c2362e6SHarvey Harrison	def_bool y
15883c2362e6SHarvey Harrison	prompt "Old style AMD Opteron NUMA detection"
15895da0ef9aSTejun Heo	depends on X86_64 && NUMA && PCI
1590a7f7f624SMasahiro Yamada	help
1591eec1d4faSHans Rosenfeld	  Enable AMD NUMA node topology detection.  You should say Y here if
1592eec1d4faSHans Rosenfeld	  you have a multi processor AMD system. This uses an old method to
1593eec1d4faSHans Rosenfeld	  read the NUMA configuration directly from the builtin Northbridge
1594eec1d4faSHans Rosenfeld	  of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1595eec1d4faSHans Rosenfeld	  which also takes priority if both are compiled in.
1596506f1d07SSam Ravnborg
1597506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA
15983c2362e6SHarvey Harrison	def_bool y
15993c2362e6SHarvey Harrison	prompt "ACPI NUMA detection"
1600506f1d07SSam Ravnborg	depends on X86_64 && NUMA && ACPI && PCI
1601506f1d07SSam Ravnborg	select ACPI_NUMA
1602a7f7f624SMasahiro Yamada	help
1603506f1d07SSam Ravnborg	  Enable ACPI SRAT based node topology detection.
1604506f1d07SSam Ravnborg
1605506f1d07SSam Ravnborgconfig NUMA_EMU
1606506f1d07SSam Ravnborg	bool "NUMA emulation"
16071b7e03efSTejun Heo	depends on NUMA
1608a7f7f624SMasahiro Yamada	help
1609506f1d07SSam Ravnborg	  Enable NUMA emulation. A flat machine will be split
1610506f1d07SSam Ravnborg	  into virtual nodes when booted with "numa=fake=N", where N is the
1611506f1d07SSam Ravnborg	  number of nodes. This is only useful for debugging.
1612506f1d07SSam Ravnborg
1613506f1d07SSam Ravnborgconfig NODES_SHIFT
1614d25e26b6SLinus Torvalds	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
161551591e31SDavid Rientjes	range 1 10
161651591e31SDavid Rientjes	default "10" if MAXSMP
1617506f1d07SSam Ravnborg	default "6" if X86_64
1618506f1d07SSam Ravnborg	default "3"
1619a9ee6cf5SMike Rapoport	depends on NUMA
1620a7f7f624SMasahiro Yamada	help
16211184dc2fSMike Travis	  Specify the maximum number of NUMA Nodes available on the target
1622692105b8SMatt LaPlante	  system.  Increases memory reserved to accommodate various tables.
1623506f1d07SSam Ravnborg
1624506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE
1625506f1d07SSam Ravnborg	def_bool y
16263b16651fSTejun Heo	depends on X86_32 && !NUMA
1627506f1d07SSam Ravnborg
1628506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE
1629506f1d07SSam Ravnborg	def_bool y
16306ea30386SKees Cook	depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1631506f1d07SSam Ravnborg	select SPARSEMEM_STATIC if X86_32
1632506f1d07SSam Ravnborg	select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1633506f1d07SSam Ravnborg
16343b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT
16356ad57f7fSMike Rapoport	def_bool X86_64 || (NUMA && X86_32)
16363b16651fSTejun Heo
1637506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL
1638506f1d07SSam Ravnborg	def_bool y
1639b263295dSChristoph Lameter	depends on ARCH_SPARSEMEM_ENABLE
1640506f1d07SSam Ravnborg
1641506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE
1642a0842b70SToshi Kani	bool "Enable sysfs memory/probe interface"
16435c11f00bSDavid Hildenbrand	depends on MEMORY_HOTPLUG
1644a0842b70SToshi Kani	help
1645a0842b70SToshi Kani	  This option enables a sysfs memory/probe interface for testing.
1646cb1aaebeSMauro Carvalho Chehab	  See Documentation/admin-guide/mm/memory-hotplug.rst for more information.
1647a0842b70SToshi Kani	  If you are unsure how to answer this question, answer N.
1648506f1d07SSam Ravnborg
16493b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT
16503b16651fSTejun Heo	def_bool y
16513b16651fSTejun Heo	depends on X86_64 && PROC_KCORE
16523b16651fSTejun Heo
1653a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE
1654a29815a3SAvi Kivity	hex
1655a29815a3SAvi Kivity	default 0 if X86_32
1656a29815a3SAvi Kivity	default 0xdead000000000000 if X86_64
1657a29815a3SAvi Kivity
16587a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE
16597a67832cSDan Williams	bool
16607a67832cSDan Williams
1661ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY
16627a67832cSDan Williams	tristate "Support non-standard NVDIMMs and ADR protected memory"
16639f53f9faSDan Williams	depends on PHYS_ADDR_T_64BIT
16649f53f9faSDan Williams	depends on BLK_DEV
16657a67832cSDan Williams	select X86_PMEM_LEGACY_DEVICE
16667b27a862SDan Williams	select NUMA_KEEP_MEMINFO if NUMA
16679f53f9faSDan Williams	select LIBNVDIMM
1668ec776ef6SChristoph Hellwig	help
1669ec776ef6SChristoph Hellwig	  Treat memory marked using the non-standard e820 type of 12 as used
1670ec776ef6SChristoph Hellwig	  by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1671ec776ef6SChristoph Hellwig	  The kernel will offer these regions to the 'pmem' driver so
1672ec776ef6SChristoph Hellwig	  they can be used for persistent storage.
1673ec776ef6SChristoph Hellwig
1674ec776ef6SChristoph Hellwig	  Say Y if unsure.
1675ec776ef6SChristoph Hellwig
1676506f1d07SSam Ravnborgconfig HIGHPTE
1677506f1d07SSam Ravnborg	bool "Allocate 3rd-level pagetables from highmem"
16786fc108a0SJan Beulich	depends on HIGHMEM
1679a7f7f624SMasahiro Yamada	help
1680506f1d07SSam Ravnborg	  The VM uses one page table entry for each page of physical memory.
1681506f1d07SSam Ravnborg	  For systems with a lot of RAM, this can be wasteful of precious
1682506f1d07SSam Ravnborg	  low memory.  Setting this option will put user-space page table
1683506f1d07SSam Ravnborg	  entries in high memory.
1684506f1d07SSam Ravnborg
16859f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION
16869f077871SJeremy Fitzhardinge	bool "Check for low memory corruption"
1687a7f7f624SMasahiro Yamada	help
16889f077871SJeremy Fitzhardinge	  Periodically check for memory corruption in low memory, which
16899f077871SJeremy Fitzhardinge	  is suspected to be caused by BIOS.  Even when enabled in the
16909f077871SJeremy Fitzhardinge	  configuration, it is disabled at runtime.  Enable it by
16919f077871SJeremy Fitzhardinge	  setting "memory_corruption_check=1" on the kernel command
16929f077871SJeremy Fitzhardinge	  line.  By default it scans the low 64k of memory every 60
16939f077871SJeremy Fitzhardinge	  seconds; see the memory_corruption_check_size and
16949f077871SJeremy Fitzhardinge	  memory_corruption_check_period parameters in
16958c27ceffSMauro Carvalho Chehab	  Documentation/admin-guide/kernel-parameters.rst to adjust this.
16969f077871SJeremy Fitzhardinge
16979f077871SJeremy Fitzhardinge	  When enabled with the default parameters, this option has
16989f077871SJeremy Fitzhardinge	  almost no overhead, as it reserves a relatively small amount
16999f077871SJeremy Fitzhardinge	  of memory and scans it infrequently.  It both detects corruption
17009f077871SJeremy Fitzhardinge	  and prevents it from affecting the running system.
17019f077871SJeremy Fitzhardinge
17029f077871SJeremy Fitzhardinge	  It is, however, intended as a diagnostic tool; if repeatable
17039f077871SJeremy Fitzhardinge	  BIOS-originated corruption always affects the same memory,
17049f077871SJeremy Fitzhardinge	  you can use memmap= to prevent the kernel from using that
17059f077871SJeremy Fitzhardinge	  memory.
17069f077871SJeremy Fitzhardinge
1707c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1708c885df50SJeremy Fitzhardinge	bool "Set the default setting of memory_corruption_check"
1709c885df50SJeremy Fitzhardinge	depends on X86_CHECK_BIOS_CORRUPTION
1710c885df50SJeremy Fitzhardinge	default y
1711a7f7f624SMasahiro Yamada	help
1712c885df50SJeremy Fitzhardinge	  Set whether the default state of memory_corruption_check is
1713c885df50SJeremy Fitzhardinge	  on or off.
1714c885df50SJeremy Fitzhardinge
1715506f1d07SSam Ravnborgconfig MATH_EMULATION
1716506f1d07SSam Ravnborg	bool
1717a5b9e5a2SAndy Lutomirski	depends on MODIFY_LDT_SYSCALL
171887d6021bSArnd Bergmann	prompt "Math emulation" if X86_32 && (M486SX || MELAN)
1719a7f7f624SMasahiro Yamada	help
1720506f1d07SSam Ravnborg	  Linux can emulate a math coprocessor (used for floating point
1721506f1d07SSam Ravnborg	  operations) if you don't have one. 486DX and Pentium processors have
1722506f1d07SSam Ravnborg	  a math coprocessor built in, 486SX and 386 do not, unless you added
1723506f1d07SSam Ravnborg	  a 487DX or 387, respectively. (The messages during boot time can
1724506f1d07SSam Ravnborg	  give you some hints here ["man dmesg"].) Everyone needs either a
1725506f1d07SSam Ravnborg	  coprocessor or this emulation.
1726506f1d07SSam Ravnborg
1727506f1d07SSam Ravnborg	  If you don't have a math coprocessor, you need to say Y here; if you
1728506f1d07SSam Ravnborg	  say Y here even though you have a coprocessor, the coprocessor will
1729506f1d07SSam Ravnborg	  be used nevertheless. (This behavior can be changed with the kernel
1730506f1d07SSam Ravnborg	  command line option "no387", which comes handy if your coprocessor
1731506f1d07SSam Ravnborg	  is broken. Try "man bootparam" or see the documentation of your boot
1732506f1d07SSam Ravnborg	  loader (lilo or loadlin) about how to pass options to the kernel at
1733506f1d07SSam Ravnborg	  boot time.) This means that it is a good idea to say Y here if you
1734506f1d07SSam Ravnborg	  intend to use this kernel on different machines.
1735506f1d07SSam Ravnborg
1736506f1d07SSam Ravnborg	  More information about the internals of the Linux math coprocessor
1737506f1d07SSam Ravnborg	  emulation can be found in <file:arch/x86/math-emu/README>.
1738506f1d07SSam Ravnborg
1739506f1d07SSam Ravnborg	  If you are not sure, say Y; apart from resulting in a 66 KB bigger
1740506f1d07SSam Ravnborg	  kernel, it won't hurt.
1741506f1d07SSam Ravnborg
1742506f1d07SSam Ravnborgconfig MTRR
17436fc108a0SJan Beulich	def_bool y
17446a108a14SDavid Rientjes	prompt "MTRR (Memory Type Range Register) support" if EXPERT
1745a7f7f624SMasahiro Yamada	help
1746506f1d07SSam Ravnborg	  On Intel P6 family processors (Pentium Pro, Pentium II and later)
1747506f1d07SSam Ravnborg	  the Memory Type Range Registers (MTRRs) may be used to control
1748506f1d07SSam Ravnborg	  processor access to memory ranges. This is most useful if you have
1749506f1d07SSam Ravnborg	  a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1750506f1d07SSam Ravnborg	  allows bus write transfers to be combined into a larger transfer
1751506f1d07SSam Ravnborg	  before bursting over the PCI/AGP bus. This can increase performance
1752506f1d07SSam Ravnborg	  of image write operations 2.5 times or more. Saying Y here creates a
1753506f1d07SSam Ravnborg	  /proc/mtrr file which may be used to manipulate your processor's
1754506f1d07SSam Ravnborg	  MTRRs. Typically the X server should use this.
1755506f1d07SSam Ravnborg
1756506f1d07SSam Ravnborg	  This code has a reasonably generic interface so that similar
1757506f1d07SSam Ravnborg	  control registers on other processors can be easily supported
1758506f1d07SSam Ravnborg	  as well:
1759506f1d07SSam Ravnborg
1760506f1d07SSam Ravnborg	  The Cyrix 6x86, 6x86MX and M II processors have Address Range
1761506f1d07SSam Ravnborg	  Registers (ARRs) which provide a similar functionality to MTRRs. For
1762506f1d07SSam Ravnborg	  these, the ARRs are used to emulate the MTRRs.
1763506f1d07SSam Ravnborg	  The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1764506f1d07SSam Ravnborg	  MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1765506f1d07SSam Ravnborg	  write-combining. All of these processors are supported by this code
1766506f1d07SSam Ravnborg	  and it makes sense to say Y here if you have one of them.
1767506f1d07SSam Ravnborg
1768506f1d07SSam Ravnborg	  Saying Y here also fixes a problem with buggy SMP BIOSes which only
1769506f1d07SSam Ravnborg	  set the MTRRs for the boot CPU and not for the secondary CPUs. This
1770506f1d07SSam Ravnborg	  can lead to all sorts of problems, so it's good to say Y here.
1771506f1d07SSam Ravnborg
1772506f1d07SSam Ravnborg	  You can safely say Y even if your machine doesn't have MTRRs, you'll
1773506f1d07SSam Ravnborg	  just add about 9 KB to your kernel.
1774506f1d07SSam Ravnborg
1775cb1aaebeSMauro Carvalho Chehab	  See <file:Documentation/x86/mtrr.rst> for more information.
1776506f1d07SSam Ravnborg
177795ffa243SYinghai Luconfig MTRR_SANITIZER
17782ffb3501SYinghai Lu	def_bool y
177995ffa243SYinghai Lu	prompt "MTRR cleanup support"
178095ffa243SYinghai Lu	depends on MTRR
1781a7f7f624SMasahiro Yamada	help
1782aba3728cSThomas Gleixner	  Convert MTRR layout from continuous to discrete, so X drivers can
1783aba3728cSThomas Gleixner	  add writeback entries.
178495ffa243SYinghai Lu
1785aba3728cSThomas Gleixner	  Can be disabled with disable_mtrr_cleanup on the kernel command line.
1786692105b8SMatt LaPlante	  The largest mtrr entry size for a continuous block can be set with
1787aba3728cSThomas Gleixner	  mtrr_chunk_size.
178895ffa243SYinghai Lu
17892ffb3501SYinghai Lu	  If unsure, say Y.
179095ffa243SYinghai Lu
179195ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT
1792f5098d62SYinghai Lu	int "MTRR cleanup enable value (0-1)"
1793f5098d62SYinghai Lu	range 0 1
1794f5098d62SYinghai Lu	default "0"
179595ffa243SYinghai Lu	depends on MTRR_SANITIZER
1796a7f7f624SMasahiro Yamada	help
1797f5098d62SYinghai Lu	  Enable mtrr cleanup default value
179895ffa243SYinghai Lu
179912031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
180012031a62SYinghai Lu	int "MTRR cleanup spare reg num (0-7)"
180112031a62SYinghai Lu	range 0 7
180212031a62SYinghai Lu	default "1"
180312031a62SYinghai Lu	depends on MTRR_SANITIZER
1804a7f7f624SMasahiro Yamada	help
180512031a62SYinghai Lu	  mtrr cleanup spare entries default, it can be changed via
1806aba3728cSThomas Gleixner	  mtrr_spare_reg_nr=N on the kernel command line.
180712031a62SYinghai Lu
18082e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT
18096fc108a0SJan Beulich	def_bool y
18106a108a14SDavid Rientjes	prompt "x86 PAT support" if EXPERT
18112a8a2719SIngo Molnar	depends on MTRR
1812a7f7f624SMasahiro Yamada	help
18132e5d9c85Svenkatesh.pallipadi@intel.com	  Use PAT attributes to setup page level cache control.
1814042b78e4SVenki Pallipadi
18152e5d9c85Svenkatesh.pallipadi@intel.com	  PATs are the modern equivalents of MTRRs and are much more
18162e5d9c85Svenkatesh.pallipadi@intel.com	  flexible than MTRRs.
18172e5d9c85Svenkatesh.pallipadi@intel.com
18182e5d9c85Svenkatesh.pallipadi@intel.com	  Say N here if you see bootup problems (boot crash, boot hang,
1819042b78e4SVenki Pallipadi	  spontaneous reboots) or a non-working video driver.
18202e5d9c85Svenkatesh.pallipadi@intel.com
18212e5d9c85Svenkatesh.pallipadi@intel.com	  If unsure, say Y.
18222e5d9c85Svenkatesh.pallipadi@intel.com
182346cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED
182446cf98cdSVenkatesh Pallipadi	def_bool y
182546cf98cdSVenkatesh Pallipadi	depends on X86_PAT
182646cf98cdSVenkatesh Pallipadi
1827628c6246SH. Peter Anvinconfig ARCH_RANDOM
1828628c6246SH. Peter Anvin	def_bool y
1829628c6246SH. Peter Anvin	prompt "x86 architectural random number generator" if EXPERT
1830a7f7f624SMasahiro Yamada	help
1831628c6246SH. Peter Anvin	  Enable the x86 architectural RDRAND instruction
1832628c6246SH. Peter Anvin	  (Intel Bull Mountain technology) to generate random numbers.
1833628c6246SH. Peter Anvin	  If supported, this is a high bandwidth, cryptographically
1834628c6246SH. Peter Anvin	  secure hardware random number generator.
1835628c6246SH. Peter Anvin
183651ae4a2dSH. Peter Anvinconfig X86_SMAP
183751ae4a2dSH. Peter Anvin	def_bool y
183851ae4a2dSH. Peter Anvin	prompt "Supervisor Mode Access Prevention" if EXPERT
1839a7f7f624SMasahiro Yamada	help
184051ae4a2dSH. Peter Anvin	  Supervisor Mode Access Prevention (SMAP) is a security
184151ae4a2dSH. Peter Anvin	  feature in newer Intel processors.  There is a small
184251ae4a2dSH. Peter Anvin	  performance cost if this enabled and turned on; there is
184351ae4a2dSH. Peter Anvin	  also a small increase in the kernel size if this is enabled.
184451ae4a2dSH. Peter Anvin
184551ae4a2dSH. Peter Anvin	  If unsure, say Y.
184651ae4a2dSH. Peter Anvin
1847b971880fSBabu Mogerconfig X86_UMIP
1848796ebc81SRicardo Neri	def_bool y
1849b971880fSBabu Moger	prompt "User Mode Instruction Prevention" if EXPERT
1850a7f7f624SMasahiro Yamada	help
1851b971880fSBabu Moger	  User Mode Instruction Prevention (UMIP) is a security feature in
1852b971880fSBabu Moger	  some x86 processors. If enabled, a general protection fault is
1853b971880fSBabu Moger	  issued if the SGDT, SLDT, SIDT, SMSW or STR instructions are
1854b971880fSBabu Moger	  executed in user mode. These instructions unnecessarily expose
1855b971880fSBabu Moger	  information about the hardware state.
1856796ebc81SRicardo Neri
1857796ebc81SRicardo Neri	  The vast majority of applications do not use these instructions.
1858796ebc81SRicardo Neri	  For the very few that do, software emulation is provided in
1859796ebc81SRicardo Neri	  specific cases in protected and virtual-8086 modes. Emulated
1860796ebc81SRicardo Neri	  results are dummy.
1861aa35f896SRicardo Neri
186235e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS
186338f3e775SBabu Moger	prompt "Memory Protection Keys"
186435e97790SDave Hansen	def_bool y
1865284244a9SDave Hansen	# Note: only available in 64-bit mode
186638f3e775SBabu Moger	depends on X86_64 && (CPU_SUP_INTEL || CPU_SUP_AMD)
186752c8e601SIngo Molnar	select ARCH_USES_HIGH_VMA_FLAGS
186852c8e601SIngo Molnar	select ARCH_HAS_PKEYS
1869a7f7f624SMasahiro Yamada	help
1870284244a9SDave Hansen	  Memory Protection Keys provides a mechanism for enforcing
1871284244a9SDave Hansen	  page-based protections, but without requiring modification of the
1872284244a9SDave Hansen	  page tables when an application changes protection domains.
1873284244a9SDave Hansen
18741eecbcdcSMauro Carvalho Chehab	  For details, see Documentation/core-api/protection-keys.rst
1875284244a9SDave Hansen
1876284244a9SDave Hansen	  If unsure, say y.
187735e97790SDave Hansen
1878db616173SMichal Hockochoice
1879db616173SMichal Hocko	prompt "TSX enable mode"
1880db616173SMichal Hocko	depends on CPU_SUP_INTEL
1881db616173SMichal Hocko	default X86_INTEL_TSX_MODE_OFF
1882db616173SMichal Hocko	help
1883db616173SMichal Hocko	  Intel's TSX (Transactional Synchronization Extensions) feature
1884db616173SMichal Hocko	  allows to optimize locking protocols through lock elision which
1885db616173SMichal Hocko	  can lead to a noticeable performance boost.
1886db616173SMichal Hocko
1887db616173SMichal Hocko	  On the other hand it has been shown that TSX can be exploited
1888db616173SMichal Hocko	  to form side channel attacks (e.g. TAA) and chances are there
1889db616173SMichal Hocko	  will be more of those attacks discovered in the future.
1890db616173SMichal Hocko
1891db616173SMichal Hocko	  Therefore TSX is not enabled by default (aka tsx=off). An admin
1892db616173SMichal Hocko	  might override this decision by tsx=on the command line parameter.
1893db616173SMichal Hocko	  Even with TSX enabled, the kernel will attempt to enable the best
1894db616173SMichal Hocko	  possible TAA mitigation setting depending on the microcode available
1895db616173SMichal Hocko	  for the particular machine.
1896db616173SMichal Hocko
1897db616173SMichal Hocko	  This option allows to set the default tsx mode between tsx=on, =off
1898db616173SMichal Hocko	  and =auto. See Documentation/admin-guide/kernel-parameters.txt for more
1899db616173SMichal Hocko	  details.
1900db616173SMichal Hocko
1901db616173SMichal Hocko	  Say off if not sure, auto if TSX is in use but it should be used on safe
1902db616173SMichal Hocko	  platforms or on if TSX is in use and the security aspect of tsx is not
1903db616173SMichal Hocko	  relevant.
1904db616173SMichal Hocko
1905db616173SMichal Hockoconfig X86_INTEL_TSX_MODE_OFF
1906db616173SMichal Hocko	bool "off"
1907db616173SMichal Hocko	help
1908db616173SMichal Hocko	  TSX is disabled if possible - equals to tsx=off command line parameter.
1909db616173SMichal Hocko
1910db616173SMichal Hockoconfig X86_INTEL_TSX_MODE_ON
1911db616173SMichal Hocko	bool "on"
1912db616173SMichal Hocko	help
1913db616173SMichal Hocko	  TSX is always enabled on TSX capable HW - equals the tsx=on command
1914db616173SMichal Hocko	  line parameter.
1915db616173SMichal Hocko
1916db616173SMichal Hockoconfig X86_INTEL_TSX_MODE_AUTO
1917db616173SMichal Hocko	bool "auto"
1918db616173SMichal Hocko	help
1919db616173SMichal Hocko	  TSX is enabled on TSX capable HW that is believed to be safe against
1920db616173SMichal Hocko	  side channel attacks- equals the tsx=auto command line parameter.
1921db616173SMichal Hockoendchoice
1922db616173SMichal Hocko
1923e7e05452SSean Christophersonconfig X86_SGX
1924e7e05452SSean Christopherson	bool "Software Guard eXtensions (SGX)"
1925e7e05452SSean Christopherson	depends on X86_64 && CPU_SUP_INTEL
1926e7e05452SSean Christopherson	depends on CRYPTO=y
1927e7e05452SSean Christopherson	depends on CRYPTO_SHA256=y
1928e7e05452SSean Christopherson	select SRCU
1929e7e05452SSean Christopherson	select MMU_NOTIFIER
1930901ddbb9SJarkko Sakkinen	select NUMA_KEEP_MEMINFO if NUMA
193140e0e784STony Luck	select XARRAY_MULTI
1932e7e05452SSean Christopherson	help
1933e7e05452SSean Christopherson	  Intel(R) Software Guard eXtensions (SGX) is a set of CPU instructions
1934e7e05452SSean Christopherson	  that can be used by applications to set aside private regions of code
1935e7e05452SSean Christopherson	  and data, referred to as enclaves. An enclave's private memory can
1936e7e05452SSean Christopherson	  only be accessed by code running within the enclave. Accesses from
1937e7e05452SSean Christopherson	  outside the enclave, including other enclaves, are disallowed by
1938e7e05452SSean Christopherson	  hardware.
1939e7e05452SSean Christopherson
1940e7e05452SSean Christopherson	  If unsure, say N.
1941e7e05452SSean Christopherson
1942506f1d07SSam Ravnborgconfig EFI
19439ba16087SJan Beulich	bool "EFI runtime service support"
19445b83683fSHuang, Ying	depends on ACPI
1945f6ce5002SSergey Vlasov	select UCS2_STRING
1946022ee6c5SArd Biesheuvel	select EFI_RUNTIME_WRAPPERS
19471ff2fc02STom Lendacky	select ARCH_USE_MEMREMAP_PROT
1948a7f7f624SMasahiro Yamada	help
19498b2cb7a8SHuang, Ying	  This enables the kernel to use EFI runtime services that are
1950506f1d07SSam Ravnborg	  available (such as the EFI variable services).
1951506f1d07SSam Ravnborg
19528b2cb7a8SHuang, Ying	  This option is only useful on systems that have EFI firmware.
19538b2cb7a8SHuang, Ying	  In addition, you should use the latest ELILO loader available
19548b2cb7a8SHuang, Ying	  at <http://elilo.sourceforge.net> in order to take advantage
19558b2cb7a8SHuang, Ying	  of EFI runtime services. However, even with this option, the
19568b2cb7a8SHuang, Ying	  resultant kernel should continue to boot on existing non-EFI
19578b2cb7a8SHuang, Ying	  platforms.
1958506f1d07SSam Ravnborg
1959291f3632SMatt Flemingconfig EFI_STUB
1960291f3632SMatt Fleming	bool "EFI stub support"
1961c6dbd3e5SPeter Zijlstra	depends on EFI
19628f24f8c2SArd Biesheuvel	depends on $(cc-option,-mabi=ms) || X86_32
19637b2a583aSMatt Fleming	select RELOCATABLE
1964a7f7f624SMasahiro Yamada	help
1965291f3632SMatt Fleming	  This kernel feature allows a bzImage to be loaded directly
1966291f3632SMatt Fleming	  by EFI firmware without the use of a bootloader.
1967291f3632SMatt Fleming
19684f4cfa6cSMauro Carvalho Chehab	  See Documentation/admin-guide/efi-stub.rst for more information.
19690c759662SMatt Fleming
19707d453eeeSMatt Flemingconfig EFI_MIXED
19717d453eeeSMatt Fleming	bool "EFI mixed-mode support"
19727d453eeeSMatt Fleming	depends on EFI_STUB && X86_64
1973a7f7f624SMasahiro Yamada	help
19747d453eeeSMatt Fleming	   Enabling this feature allows a 64-bit kernel to be booted
19757d453eeeSMatt Fleming	   on a 32-bit firmware, provided that your CPU supports 64-bit
19767d453eeeSMatt Fleming	   mode.
19777d453eeeSMatt Fleming
19787d453eeeSMatt Fleming	   Note that it is not possible to boot a mixed-mode enabled
19797d453eeeSMatt Fleming	   kernel via the EFI boot stub - a bootloader that supports
19807d453eeeSMatt Fleming	   the EFI handover protocol must be used.
19817d453eeeSMatt Fleming
19827d453eeeSMatt Fleming	   If unsure, say N.
19837d453eeeSMatt Fleming
19848636a1f9SMasahiro Yamadasource "kernel/Kconfig.hz"
1985506f1d07SSam Ravnborg
1986506f1d07SSam Ravnborgconfig KEXEC
1987506f1d07SSam Ravnborg	bool "kexec system call"
19882965faa5SDave Young	select KEXEC_CORE
1989a7f7f624SMasahiro Yamada	help
1990506f1d07SSam Ravnborg	  kexec is a system call that implements the ability to shutdown your
1991506f1d07SSam Ravnborg	  current kernel, and to start another kernel.  It is like a reboot
1992506f1d07SSam Ravnborg	  but it is independent of the system firmware.   And like a reboot
1993506f1d07SSam Ravnborg	  you can start any kernel with it, not just Linux.
1994506f1d07SSam Ravnborg
1995506f1d07SSam Ravnborg	  The name comes from the similarity to the exec system call.
1996506f1d07SSam Ravnborg
1997506f1d07SSam Ravnborg	  It is an ongoing process to be certain the hardware in a machine
1998506f1d07SSam Ravnborg	  is properly shutdown, so do not be surprised if this code does not
1999bf220695SGeert Uytterhoeven	  initially work for you.  As of this writing the exact hardware
2000bf220695SGeert Uytterhoeven	  interface is strongly in flux, so no good recommendation can be
2001bf220695SGeert Uytterhoeven	  made.
2002506f1d07SSam Ravnborg
200374ca317cSVivek Goyalconfig KEXEC_FILE
200474ca317cSVivek Goyal	bool "kexec file based system call"
20052965faa5SDave Young	select KEXEC_CORE
200674ca317cSVivek Goyal	select BUILD_BIN2C
200774ca317cSVivek Goyal	depends on X86_64
200874ca317cSVivek Goyal	depends on CRYPTO=y
200974ca317cSVivek Goyal	depends on CRYPTO_SHA256=y
2010a7f7f624SMasahiro Yamada	help
201174ca317cSVivek Goyal	  This is new version of kexec system call. This system call is
201274ca317cSVivek Goyal	  file based and takes file descriptors as system call argument
201374ca317cSVivek Goyal	  for kernel and initramfs as opposed to list of segments as
201474ca317cSVivek Goyal	  accepted by previous system call.
201574ca317cSVivek Goyal
2016b799a09fSAKASHI Takahiroconfig ARCH_HAS_KEXEC_PURGATORY
2017b799a09fSAKASHI Takahiro	def_bool KEXEC_FILE
2018b799a09fSAKASHI Takahiro
201999d5cadfSJiri Bohacconfig KEXEC_SIG
20208e7d8381SVivek Goyal	bool "Verify kernel signature during kexec_file_load() syscall"
202174ca317cSVivek Goyal	depends on KEXEC_FILE
2022a7f7f624SMasahiro Yamada	help
202399d5cadfSJiri Bohac
202499d5cadfSJiri Bohac	  This option makes the kexec_file_load() syscall check for a valid
202599d5cadfSJiri Bohac	  signature of the kernel image.  The image can still be loaded without
202699d5cadfSJiri Bohac	  a valid signature unless you also enable KEXEC_SIG_FORCE, though if
202799d5cadfSJiri Bohac	  there's a signature that we can check, then it must be valid.
202899d5cadfSJiri Bohac
202999d5cadfSJiri Bohac	  In addition to this option, you need to enable signature
203099d5cadfSJiri Bohac	  verification for the corresponding kernel image type being
203199d5cadfSJiri Bohac	  loaded in order for this to work.
203299d5cadfSJiri Bohac
203399d5cadfSJiri Bohacconfig KEXEC_SIG_FORCE
203499d5cadfSJiri Bohac	bool "Require a valid signature in kexec_file_load() syscall"
203599d5cadfSJiri Bohac	depends on KEXEC_SIG
2036a7f7f624SMasahiro Yamada	help
20378e7d8381SVivek Goyal	  This option makes kernel signature verification mandatory for
2038d8eb8940SBorislav Petkov	  the kexec_file_load() syscall.
20398e7d8381SVivek Goyal
20408e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG
20418e7d8381SVivek Goyal	bool "Enable bzImage signature verification support"
204299d5cadfSJiri Bohac	depends on KEXEC_SIG
20438e7d8381SVivek Goyal	depends on SIGNED_PE_FILE_VERIFICATION
20448e7d8381SVivek Goyal	select SYSTEM_TRUSTED_KEYRING
2045a7f7f624SMasahiro Yamada	help
20468e7d8381SVivek Goyal	  Enable bzImage signature verification support.
20478e7d8381SVivek Goyal
2048506f1d07SSam Ravnborgconfig CRASH_DUMP
204904b69447SPavel Machek	bool "kernel crash dumps"
2050506f1d07SSam Ravnborg	depends on X86_64 || (X86_32 && HIGHMEM)
2051a7f7f624SMasahiro Yamada	help
2052506f1d07SSam Ravnborg	  Generate crash dump after being started by kexec.
2053506f1d07SSam Ravnborg	  This should be normally only set in special crash dump kernels
2054506f1d07SSam Ravnborg	  which are loaded in the main kernel with kexec-tools into
2055506f1d07SSam Ravnborg	  a specially reserved region and then later executed after
2056506f1d07SSam Ravnborg	  a crash by kdump/kexec. The crash dump kernel must be compiled
2057506f1d07SSam Ravnborg	  to a memory address not used by the main kernel or BIOS using
2058506f1d07SSam Ravnborg	  PHYSICAL_START, or it must be built as a relocatable image
2059506f1d07SSam Ravnborg	  (CONFIG_RELOCATABLE=y).
2060330d4810SMauro Carvalho Chehab	  For more details see Documentation/admin-guide/kdump/kdump.rst
2061506f1d07SSam Ravnborg
20623ab83521SHuang Yingconfig KEXEC_JUMP
20636ea30386SKees Cook	bool "kexec jump"
2064fee7b0d8SHuang Ying	depends on KEXEC && HIBERNATION
2065a7f7f624SMasahiro Yamada	help
206689081d17SHuang Ying	  Jump between original kernel and kexeced kernel and invoke
206789081d17SHuang Ying	  code in physical address mode via KEXEC
20683ab83521SHuang Ying
2069506f1d07SSam Ravnborgconfig PHYSICAL_START
20706a108a14SDavid Rientjes	hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
2071ceefccc9SH. Peter Anvin	default "0x1000000"
2072a7f7f624SMasahiro Yamada	help
2073506f1d07SSam Ravnborg	  This gives the physical address where the kernel is loaded.
2074506f1d07SSam Ravnborg
2075506f1d07SSam Ravnborg	  If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2076506f1d07SSam Ravnborg	  bzImage will decompress itself to above physical address and
2077506f1d07SSam Ravnborg	  run from there. Otherwise, bzImage will run from the address where
2078506f1d07SSam Ravnborg	  it has been loaded by the boot loader and will ignore above physical
2079506f1d07SSam Ravnborg	  address.
2080506f1d07SSam Ravnborg
2081506f1d07SSam Ravnborg	  In normal kdump cases one does not have to set/change this option
2082506f1d07SSam Ravnborg	  as now bzImage can be compiled as a completely relocatable image
2083506f1d07SSam Ravnborg	  (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2084506f1d07SSam Ravnborg	  address. This option is mainly useful for the folks who don't want
2085506f1d07SSam Ravnborg	  to use a bzImage for capturing the crash dump and want to use a
2086506f1d07SSam Ravnborg	  vmlinux instead. vmlinux is not relocatable hence a kernel needs
2087506f1d07SSam Ravnborg	  to be specifically compiled to run from a specific memory area
2088506f1d07SSam Ravnborg	  (normally a reserved region) and this option comes handy.
2089506f1d07SSam Ravnborg
2090ceefccc9SH. Peter Anvin	  So if you are using bzImage for capturing the crash dump,
2091ceefccc9SH. Peter Anvin	  leave the value here unchanged to 0x1000000 and set
2092ceefccc9SH. Peter Anvin	  CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
2093ceefccc9SH. Peter Anvin	  for capturing the crash dump change this value to start of
2094ceefccc9SH. Peter Anvin	  the reserved region.  In other words, it can be set based on
2095ceefccc9SH. Peter Anvin	  the "X" value as specified in the "crashkernel=YM@XM"
2096ceefccc9SH. Peter Anvin	  command line boot parameter passed to the panic-ed
2097330d4810SMauro Carvalho Chehab	  kernel. Please take a look at Documentation/admin-guide/kdump/kdump.rst
2098ceefccc9SH. Peter Anvin	  for more details about crash dumps.
2099506f1d07SSam Ravnborg
2100506f1d07SSam Ravnborg	  Usage of bzImage for capturing the crash dump is recommended as
2101506f1d07SSam Ravnborg	  one does not have to build two kernels. Same kernel can be used
2102506f1d07SSam Ravnborg	  as production kernel and capture kernel. Above option should have
2103506f1d07SSam Ravnborg	  gone away after relocatable bzImage support is introduced. But it
2104506f1d07SSam Ravnborg	  is present because there are users out there who continue to use
2105506f1d07SSam Ravnborg	  vmlinux for dump capture. This option should go away down the
2106506f1d07SSam Ravnborg	  line.
2107506f1d07SSam Ravnborg
2108506f1d07SSam Ravnborg	  Don't change this unless you know what you are doing.
2109506f1d07SSam Ravnborg
2110506f1d07SSam Ravnborgconfig RELOCATABLE
211126717808SH. Peter Anvin	bool "Build a relocatable kernel"
211226717808SH. Peter Anvin	default y
2113a7f7f624SMasahiro Yamada	help
2114506f1d07SSam Ravnborg	  This builds a kernel image that retains relocation information
2115506f1d07SSam Ravnborg	  so it can be loaded someplace besides the default 1MB.
2116506f1d07SSam Ravnborg	  The relocations tend to make the kernel binary about 10% larger,
2117506f1d07SSam Ravnborg	  but are discarded at runtime.
2118506f1d07SSam Ravnborg
2119506f1d07SSam Ravnborg	  One use is for the kexec on panic case where the recovery kernel
2120506f1d07SSam Ravnborg	  must live at a different physical address than the primary
2121506f1d07SSam Ravnborg	  kernel.
2122506f1d07SSam Ravnborg
2123506f1d07SSam Ravnborg	  Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2124506f1d07SSam Ravnborg	  it has been loaded at and the compile time physical address
21258ab3820fSKees Cook	  (CONFIG_PHYSICAL_START) is used as the minimum location.
2126506f1d07SSam Ravnborg
21278ab3820fSKees Cookconfig RANDOMIZE_BASE
2128e8581e3dSBaoquan He	bool "Randomize the address of the kernel image (KASLR)"
21298ab3820fSKees Cook	depends on RELOCATABLE
21306807c846SIngo Molnar	default y
2131a7f7f624SMasahiro Yamada	help
2132e8581e3dSBaoquan He	  In support of Kernel Address Space Layout Randomization (KASLR),
2133e8581e3dSBaoquan He	  this randomizes the physical address at which the kernel image
2134e8581e3dSBaoquan He	  is decompressed and the virtual address where the kernel
2135e8581e3dSBaoquan He	  image is mapped, as a security feature that deters exploit
2136e8581e3dSBaoquan He	  attempts relying on knowledge of the location of kernel
2137e8581e3dSBaoquan He	  code internals.
2138e8581e3dSBaoquan He
2139ed9f007eSKees Cook	  On 64-bit, the kernel physical and virtual addresses are
2140ed9f007eSKees Cook	  randomized separately. The physical address will be anywhere
2141ed9f007eSKees Cook	  between 16MB and the top of physical memory (up to 64TB). The
2142ed9f007eSKees Cook	  virtual address will be randomized from 16MB up to 1GB (9 bits
2143ed9f007eSKees Cook	  of entropy). Note that this also reduces the memory space
2144ed9f007eSKees Cook	  available to kernel modules from 1.5GB to 1GB.
2145ed9f007eSKees Cook
2146ed9f007eSKees Cook	  On 32-bit, the kernel physical and virtual addresses are
2147ed9f007eSKees Cook	  randomized together. They will be randomized from 16MB up to
2148ed9f007eSKees Cook	  512MB (8 bits of entropy).
21498ab3820fSKees Cook
2150a653f356SKees Cook	  Entropy is generated using the RDRAND instruction if it is
2151e8581e3dSBaoquan He	  supported. If RDTSC is supported, its value is mixed into
2152e8581e3dSBaoquan He	  the entropy pool as well. If neither RDRAND nor RDTSC are
2153ed9f007eSKees Cook	  supported, then entropy is read from the i8254 timer. The
2154ed9f007eSKees Cook	  usable entropy is limited by the kernel being built using
2155ed9f007eSKees Cook	  2GB addressing, and that PHYSICAL_ALIGN must be at a
2156ed9f007eSKees Cook	  minimum of 2MB. As a result, only 10 bits of entropy are
2157ed9f007eSKees Cook	  theoretically possible, but the implementations are further
2158ed9f007eSKees Cook	  limited due to memory layouts.
2159e8581e3dSBaoquan He
21606807c846SIngo Molnar	  If unsure, say Y.
2161da2b6fb9SKees Cook
21628ab3820fSKees Cook# Relocation on x86 needs some additional build support
2163845adf72SH. Peter Anvinconfig X86_NEED_RELOCS
2164845adf72SH. Peter Anvin	def_bool y
21658ab3820fSKees Cook	depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
2166845adf72SH. Peter Anvin
2167506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN
2168a0215061SKees Cook	hex "Alignment value to which kernel should be aligned"
21698ab3820fSKees Cook	default "0x200000"
2170a0215061SKees Cook	range 0x2000 0x1000000 if X86_32
2171a0215061SKees Cook	range 0x200000 0x1000000 if X86_64
2172a7f7f624SMasahiro Yamada	help
2173506f1d07SSam Ravnborg	  This value puts the alignment restrictions on physical address
2174506f1d07SSam Ravnborg	  where kernel is loaded and run from. Kernel is compiled for an
2175506f1d07SSam Ravnborg	  address which meets above alignment restriction.
2176506f1d07SSam Ravnborg
2177506f1d07SSam Ravnborg	  If bootloader loads the kernel at a non-aligned address and
2178506f1d07SSam Ravnborg	  CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2179506f1d07SSam Ravnborg	  address aligned to above value and run from there.
2180506f1d07SSam Ravnborg
2181506f1d07SSam Ravnborg	  If bootloader loads the kernel at a non-aligned address and
2182506f1d07SSam Ravnborg	  CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2183506f1d07SSam Ravnborg	  load address and decompress itself to the address it has been
2184506f1d07SSam Ravnborg	  compiled for and run from there. The address for which kernel is
2185506f1d07SSam Ravnborg	  compiled already meets above alignment restrictions. Hence the
2186506f1d07SSam Ravnborg	  end result is that kernel runs from a physical address meeting
2187506f1d07SSam Ravnborg	  above alignment restrictions.
2188506f1d07SSam Ravnborg
2189a0215061SKees Cook	  On 32-bit this value must be a multiple of 0x2000. On 64-bit
2190a0215061SKees Cook	  this value must be a multiple of 0x200000.
2191a0215061SKees Cook
2192506f1d07SSam Ravnborg	  Don't change this unless you know what you are doing.
2193506f1d07SSam Ravnborg
2194eedb92abSKirill A. Shutemovconfig DYNAMIC_MEMORY_LAYOUT
2195eedb92abSKirill A. Shutemov	bool
2196a7f7f624SMasahiro Yamada	help
2197eedb92abSKirill A. Shutemov	  This option makes base addresses of vmalloc and vmemmap as well as
2198eedb92abSKirill A. Shutemov	  __PAGE_OFFSET movable during boot.
2199eedb92abSKirill A. Shutemov
22000483e1faSThomas Garnierconfig RANDOMIZE_MEMORY
22010483e1faSThomas Garnier	bool "Randomize the kernel memory sections"
22020483e1faSThomas Garnier	depends on X86_64
22030483e1faSThomas Garnier	depends on RANDOMIZE_BASE
2204eedb92abSKirill A. Shutemov	select DYNAMIC_MEMORY_LAYOUT
22050483e1faSThomas Garnier	default RANDOMIZE_BASE
2206a7f7f624SMasahiro Yamada	help
22070483e1faSThomas Garnier	   Randomizes the base virtual address of kernel memory sections
22080483e1faSThomas Garnier	   (physical memory mapping, vmalloc & vmemmap). This security feature
22090483e1faSThomas Garnier	   makes exploits relying on predictable memory locations less reliable.
22100483e1faSThomas Garnier
22110483e1faSThomas Garnier	   The order of allocations remains unchanged. Entropy is generated in
22120483e1faSThomas Garnier	   the same way as RANDOMIZE_BASE. Current implementation in the optimal
22130483e1faSThomas Garnier	   configuration have in average 30,000 different possible virtual
22140483e1faSThomas Garnier	   addresses for each memory section.
22150483e1faSThomas Garnier
22166807c846SIngo Molnar	   If unsure, say Y.
22170483e1faSThomas Garnier
221890397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING
221990397a41SThomas Garnier	hex "Physical memory mapping padding" if EXPERT
222090397a41SThomas Garnier	depends on RANDOMIZE_MEMORY
222190397a41SThomas Garnier	default "0xa" if MEMORY_HOTPLUG
222290397a41SThomas Garnier	default "0x0"
222390397a41SThomas Garnier	range 0x1 0x40 if MEMORY_HOTPLUG
222490397a41SThomas Garnier	range 0x0 0x40
2225a7f7f624SMasahiro Yamada	help
222690397a41SThomas Garnier	   Define the padding in terabytes added to the existing physical
222790397a41SThomas Garnier	   memory size during kernel memory randomization. It is useful
222890397a41SThomas Garnier	   for memory hotplug support but reduces the entropy available for
222990397a41SThomas Garnier	   address randomization.
223090397a41SThomas Garnier
223190397a41SThomas Garnier	   If unsure, leave at the default value.
223290397a41SThomas Garnier
2233506f1d07SSam Ravnborgconfig HOTPLUG_CPU
2234bebd024eSThomas Gleixner	def_bool y
223540b31360SStephen Rothwell	depends on SMP
2236506f1d07SSam Ravnborg
223780aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0
223880aa1dffSFenghua Yu	bool "Set default setting of cpu0_hotpluggable"
22392c922cd0SKees Cook	depends on HOTPLUG_CPU
2240a7f7f624SMasahiro Yamada	help
224180aa1dffSFenghua Yu	  Set whether default state of cpu0_hotpluggable is on or off.
224280aa1dffSFenghua Yu
224380aa1dffSFenghua Yu	  Say Y here to enable CPU0 hotplug by default. If this switch
224480aa1dffSFenghua Yu	  is turned on, there is no need to give cpu0_hotplug kernel
224580aa1dffSFenghua Yu	  parameter and the CPU0 hotplug feature is enabled by default.
224680aa1dffSFenghua Yu
224780aa1dffSFenghua Yu	  Please note: there are two known CPU0 dependencies if you want
224880aa1dffSFenghua Yu	  to enable the CPU0 hotplug feature either by this switch or by
224980aa1dffSFenghua Yu	  cpu0_hotplug kernel parameter.
225080aa1dffSFenghua Yu
225180aa1dffSFenghua Yu	  First, resume from hibernate or suspend always starts from CPU0.
225280aa1dffSFenghua Yu	  So hibernate and suspend are prevented if CPU0 is offline.
225380aa1dffSFenghua Yu
225480aa1dffSFenghua Yu	  Second dependency is PIC interrupts always go to CPU0. CPU0 can not
225580aa1dffSFenghua Yu	  offline if any interrupt can not migrate out of CPU0. There may
225680aa1dffSFenghua Yu	  be other CPU0 dependencies.
225780aa1dffSFenghua Yu
225880aa1dffSFenghua Yu	  Please make sure the dependencies are under your control before
225980aa1dffSFenghua Yu	  you enable this feature.
226080aa1dffSFenghua Yu
226180aa1dffSFenghua Yu	  Say N if you don't want to enable CPU0 hotplug feature by default.
226280aa1dffSFenghua Yu	  You still can enable the CPU0 hotplug feature at boot by kernel
226380aa1dffSFenghua Yu	  parameter cpu0_hotplug.
226480aa1dffSFenghua Yu
2265a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0
2266a71c8bc5SFenghua Yu	def_bool n
2267a71c8bc5SFenghua Yu	prompt "Debug CPU0 hotplug"
22682c922cd0SKees Cook	depends on HOTPLUG_CPU
2269a7f7f624SMasahiro Yamada	help
2270a71c8bc5SFenghua Yu	  Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2271a71c8bc5SFenghua Yu	  soon as possible and boots up userspace with CPU0 offlined. User
2272a71c8bc5SFenghua Yu	  can online CPU0 back after boot time.
2273a71c8bc5SFenghua Yu
2274a71c8bc5SFenghua Yu	  To debug CPU0 hotplug, you need to enable CPU0 offline/online
2275a71c8bc5SFenghua Yu	  feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2276a71c8bc5SFenghua Yu	  compilation or giving cpu0_hotplug kernel parameter at boot.
2277a71c8bc5SFenghua Yu
2278a71c8bc5SFenghua Yu	  If unsure, say N.
2279a71c8bc5SFenghua Yu
2280506f1d07SSam Ravnborgconfig COMPAT_VDSO
2281b0b49f26SAndy Lutomirski	def_bool n
2282b0b49f26SAndy Lutomirski	prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
2283953fee1dSIngo Molnar	depends on COMPAT_32
2284a7f7f624SMasahiro Yamada	help
2285b0b49f26SAndy Lutomirski	  Certain buggy versions of glibc will crash if they are
2286b0b49f26SAndy Lutomirski	  presented with a 32-bit vDSO that is not mapped at the address
2287b0b49f26SAndy Lutomirski	  indicated in its segment table.
2288e84446deSRandy Dunlap
2289b0b49f26SAndy Lutomirski	  The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2290b0b49f26SAndy Lutomirski	  and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2291b0b49f26SAndy Lutomirski	  49ad572a70b8aeb91e57483a11dd1b77e31c4468.  Glibc 2.3.3 is
2292b0b49f26SAndy Lutomirski	  the only released version with the bug, but OpenSUSE 9
2293b0b49f26SAndy Lutomirski	  contains a buggy "glibc 2.3.2".
2294506f1d07SSam Ravnborg
2295b0b49f26SAndy Lutomirski	  The symptom of the bug is that everything crashes on startup, saying:
2296b0b49f26SAndy Lutomirski	  dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2297b0b49f26SAndy Lutomirski
2298b0b49f26SAndy Lutomirski	  Saying Y here changes the default value of the vdso32 boot
2299b0b49f26SAndy Lutomirski	  option from 1 to 0, which turns off the 32-bit vDSO entirely.
2300b0b49f26SAndy Lutomirski	  This works around the glibc bug but hurts performance.
2301b0b49f26SAndy Lutomirski
2302b0b49f26SAndy Lutomirski	  If unsure, say N: if you are compiling your own kernel, you
2303b0b49f26SAndy Lutomirski	  are unlikely to be using a buggy version of glibc.
2304506f1d07SSam Ravnborg
23053dc33bd3SKees Cookchoice
23063dc33bd3SKees Cook	prompt "vsyscall table for legacy applications"
23073dc33bd3SKees Cook	depends on X86_64
2308625b7b7fSAndy Lutomirski	default LEGACY_VSYSCALL_XONLY
23093dc33bd3SKees Cook	help
23103dc33bd3SKees Cook	  Legacy user code that does not know how to find the vDSO expects
23113dc33bd3SKees Cook	  to be able to issue three syscalls by calling fixed addresses in
23123dc33bd3SKees Cook	  kernel space. Since this location is not randomized with ASLR,
23133dc33bd3SKees Cook	  it can be used to assist security vulnerability exploitation.
23143dc33bd3SKees Cook
23153dc33bd3SKees Cook	  This setting can be changed at boot time via the kernel command
2316bd49e16eSAndy Lutomirski	  line parameter vsyscall=[emulate|xonly|none].
23173dc33bd3SKees Cook
23183dc33bd3SKees Cook	  On a system with recent enough glibc (2.14 or newer) and no
23193dc33bd3SKees Cook	  static binaries, you can say None without a performance penalty
23203dc33bd3SKees Cook	  to improve security.
23213dc33bd3SKees Cook
2322bd49e16eSAndy Lutomirski	  If unsure, select "Emulate execution only".
23233dc33bd3SKees Cook
23243dc33bd3SKees Cook	config LEGACY_VSYSCALL_EMULATE
2325bd49e16eSAndy Lutomirski		bool "Full emulation"
23263dc33bd3SKees Cook		help
2327bd49e16eSAndy Lutomirski		  The kernel traps and emulates calls into the fixed vsyscall
2328bd49e16eSAndy Lutomirski		  address mapping. This makes the mapping non-executable, but
2329bd49e16eSAndy Lutomirski		  it still contains readable known contents, which could be
2330bd49e16eSAndy Lutomirski		  used in certain rare security vulnerability exploits. This
2331bd49e16eSAndy Lutomirski		  configuration is recommended when using legacy userspace
2332bd49e16eSAndy Lutomirski		  that still uses vsyscalls along with legacy binary
2333bd49e16eSAndy Lutomirski		  instrumentation tools that require code to be readable.
2334bd49e16eSAndy Lutomirski
2335bd49e16eSAndy Lutomirski		  An example of this type of legacy userspace is running
2336bd49e16eSAndy Lutomirski		  Pin on an old binary that still uses vsyscalls.
2337bd49e16eSAndy Lutomirski
2338bd49e16eSAndy Lutomirski	config LEGACY_VSYSCALL_XONLY
2339bd49e16eSAndy Lutomirski		bool "Emulate execution only"
2340bd49e16eSAndy Lutomirski		help
2341bd49e16eSAndy Lutomirski		  The kernel traps and emulates calls into the fixed vsyscall
2342bd49e16eSAndy Lutomirski		  address mapping and does not allow reads.  This
2343bd49e16eSAndy Lutomirski		  configuration is recommended when userspace might use the
2344bd49e16eSAndy Lutomirski		  legacy vsyscall area but support for legacy binary
2345bd49e16eSAndy Lutomirski		  instrumentation of legacy code is not needed.  It mitigates
2346bd49e16eSAndy Lutomirski		  certain uses of the vsyscall area as an ASLR-bypassing
2347bd49e16eSAndy Lutomirski		  buffer.
23483dc33bd3SKees Cook
23493dc33bd3SKees Cook	config LEGACY_VSYSCALL_NONE
23503dc33bd3SKees Cook		bool "None"
23513dc33bd3SKees Cook		help
23523dc33bd3SKees Cook		  There will be no vsyscall mapping at all. This will
23533dc33bd3SKees Cook		  eliminate any risk of ASLR bypass due to the vsyscall
23543dc33bd3SKees Cook		  fixed address mapping. Attempts to use the vsyscalls
23553dc33bd3SKees Cook		  will be reported to dmesg, so that either old or
23563dc33bd3SKees Cook		  malicious userspace programs can be identified.
23573dc33bd3SKees Cook
23583dc33bd3SKees Cookendchoice
23593dc33bd3SKees Cook
2360516cbf37STim Birdconfig CMDLINE_BOOL
2361516cbf37STim Bird	bool "Built-in kernel command line"
2362a7f7f624SMasahiro Yamada	help
2363516cbf37STim Bird	  Allow for specifying boot arguments to the kernel at
2364516cbf37STim Bird	  build time.  On some systems (e.g. embedded ones), it is
2365516cbf37STim Bird	  necessary or convenient to provide some or all of the
2366516cbf37STim Bird	  kernel boot arguments with the kernel itself (that is,
2367516cbf37STim Bird	  to not rely on the boot loader to provide them.)
2368516cbf37STim Bird
2369516cbf37STim Bird	  To compile command line arguments into the kernel,
2370516cbf37STim Bird	  set this option to 'Y', then fill in the
237169711ca1SSébastien Hinderer	  boot arguments in CONFIG_CMDLINE.
2372516cbf37STim Bird
2373516cbf37STim Bird	  Systems with fully functional boot loaders (i.e. non-embedded)
2374516cbf37STim Bird	  should leave this option set to 'N'.
2375516cbf37STim Bird
2376516cbf37STim Birdconfig CMDLINE
2377516cbf37STim Bird	string "Built-in kernel command string"
2378516cbf37STim Bird	depends on CMDLINE_BOOL
2379516cbf37STim Bird	default ""
2380a7f7f624SMasahiro Yamada	help
2381516cbf37STim Bird	  Enter arguments here that should be compiled into the kernel
2382516cbf37STim Bird	  image and used at boot time.  If the boot loader provides a
2383516cbf37STim Bird	  command line at boot time, it is appended to this string to
2384516cbf37STim Bird	  form the full kernel command line, when the system boots.
2385516cbf37STim Bird
2386516cbf37STim Bird	  However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2387516cbf37STim Bird	  change this behavior.
2388516cbf37STim Bird
2389516cbf37STim Bird	  In most cases, the command line (whether built-in or provided
2390516cbf37STim Bird	  by the boot loader) should specify the device for the root
2391516cbf37STim Bird	  file system.
2392516cbf37STim Bird
2393516cbf37STim Birdconfig CMDLINE_OVERRIDE
2394516cbf37STim Bird	bool "Built-in command line overrides boot loader arguments"
2395645e6466SAnders Roxell	depends on CMDLINE_BOOL && CMDLINE != ""
2396a7f7f624SMasahiro Yamada	help
2397516cbf37STim Bird	  Set this option to 'Y' to have the kernel ignore the boot loader
2398516cbf37STim Bird	  command line, and use ONLY the built-in command line.
2399516cbf37STim Bird
2400516cbf37STim Bird	  This is used to work around broken boot loaders.  This should
2401516cbf37STim Bird	  be set to 'N' under normal conditions.
2402516cbf37STim Bird
2403a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL
2404a5b9e5a2SAndy Lutomirski	bool "Enable the LDT (local descriptor table)" if EXPERT
2405a5b9e5a2SAndy Lutomirski	default y
2406a7f7f624SMasahiro Yamada	help
2407a5b9e5a2SAndy Lutomirski	  Linux can allow user programs to install a per-process x86
2408a5b9e5a2SAndy Lutomirski	  Local Descriptor Table (LDT) using the modify_ldt(2) system
2409a5b9e5a2SAndy Lutomirski	  call.  This is required to run 16-bit or segmented code such as
2410a5b9e5a2SAndy Lutomirski	  DOSEMU or some Wine programs.  It is also used by some very old
2411a5b9e5a2SAndy Lutomirski	  threading libraries.
2412a5b9e5a2SAndy Lutomirski
2413a5b9e5a2SAndy Lutomirski	  Enabling this feature adds a small amount of overhead to
2414a5b9e5a2SAndy Lutomirski	  context switches and increases the low-level kernel attack
2415a5b9e5a2SAndy Lutomirski	  surface.  Disabling it removes the modify_ldt(2) system call.
2416a5b9e5a2SAndy Lutomirski
2417a5b9e5a2SAndy Lutomirski	  Saying 'N' here may make sense for embedded or server kernels.
2418a5b9e5a2SAndy Lutomirski
24193aac3ebeSThomas Gleixnerconfig STRICT_SIGALTSTACK_SIZE
24203aac3ebeSThomas Gleixner	bool "Enforce strict size checking for sigaltstack"
24213aac3ebeSThomas Gleixner	depends on DYNAMIC_SIGFRAME
24223aac3ebeSThomas Gleixner	help
24233aac3ebeSThomas Gleixner	  For historical reasons MINSIGSTKSZ is a constant which became
24243aac3ebeSThomas Gleixner	  already too small with AVX512 support. Add a mechanism to
24253aac3ebeSThomas Gleixner	  enforce strict checking of the sigaltstack size against the
24263aac3ebeSThomas Gleixner	  real size of the FPU frame. This option enables the check
24273aac3ebeSThomas Gleixner	  by default. It can also be controlled via the kernel command
24283aac3ebeSThomas Gleixner	  line option 'strict_sas_size' independent of this config
24293aac3ebeSThomas Gleixner	  switch. Enabling it might break existing applications which
24303aac3ebeSThomas Gleixner	  allocate a too small sigaltstack but 'work' because they
24313aac3ebeSThomas Gleixner	  never get a signal delivered.
24323aac3ebeSThomas Gleixner
24333aac3ebeSThomas Gleixner	  Say 'N' unless you want to really enforce this check.
24343aac3ebeSThomas Gleixner
2435b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig"
2436b700e7f0SSeth Jennings
2437506f1d07SSam Ravnborgendmenu
2438506f1d07SSam Ravnborg
24393072e413SMichal Hockoconfig ARCH_HAS_ADD_PAGES
24403072e413SMichal Hocko	def_bool y
24415c11f00bSDavid Hildenbrand	depends on ARCH_ENABLE_MEMORY_HOTPLUG
24423072e413SMichal Hocko
2443f91ef222SOscar Salvadorconfig ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
2444f91ef222SOscar Salvador	def_bool y
2445f91ef222SOscar Salvador
2446da85f865SBjorn Helgaasmenu "Power management and ACPI options"
2447e279b6c1SSam Ravnborg
2448e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER
24493c2362e6SHarvey Harrison	def_bool y
245044556530SZhimin Gu	depends on HIBERNATION
2451e279b6c1SSam Ravnborg
2452e279b6c1SSam Ravnborgsource "kernel/power/Kconfig"
2453e279b6c1SSam Ravnborg
2454e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig"
2455e279b6c1SSam Ravnborg
2456a6b68076SAndi Kleenconfig X86_APM_BOOT
24576fc108a0SJan Beulich	def_bool y
2458282e5aabSPaul Bolle	depends on APM
2459a6b68076SAndi Kleen
2460e279b6c1SSam Ravnborgmenuconfig APM
2461e279b6c1SSam Ravnborg	tristate "APM (Advanced Power Management) BIOS support"
2462efefa6f6SIngo Molnar	depends on X86_32 && PM_SLEEP
2463a7f7f624SMasahiro Yamada	help
2464e279b6c1SSam Ravnborg	  APM is a BIOS specification for saving power using several different
2465e279b6c1SSam Ravnborg	  techniques. This is mostly useful for battery powered laptops with
2466e279b6c1SSam Ravnborg	  APM compliant BIOSes. If you say Y here, the system time will be
2467e279b6c1SSam Ravnborg	  reset after a RESUME operation, the /proc/apm device will provide
2468e279b6c1SSam Ravnborg	  battery status information, and user-space programs will receive
2469e279b6c1SSam Ravnborg	  notification of APM "events" (e.g. battery status change).
2470e279b6c1SSam Ravnborg
2471e279b6c1SSam Ravnborg	  If you select "Y" here, you can disable actual use of the APM
2472e279b6c1SSam Ravnborg	  BIOS by passing the "apm=off" option to the kernel at boot time.
2473e279b6c1SSam Ravnborg
2474e279b6c1SSam Ravnborg	  Note that the APM support is almost completely disabled for
2475e279b6c1SSam Ravnborg	  machines with more than one CPU.
2476e279b6c1SSam Ravnborg
2477e279b6c1SSam Ravnborg	  In order to use APM, you will need supporting software. For location
2478151f4e2bSMauro Carvalho Chehab	  and more information, read <file:Documentation/power/apm-acpi.rst>
24792dc98fd3SMichael Witten	  and the Battery Powered Linux mini-HOWTO, available from
2480e279b6c1SSam Ravnborg	  <http://www.tldp.org/docs.html#howto>.
2481e279b6c1SSam Ravnborg
2482e279b6c1SSam Ravnborg	  This driver does not spin down disk drives (see the hdparm(8)
2483e279b6c1SSam Ravnborg	  manpage ("man 8 hdparm") for that), and it doesn't turn off
2484e279b6c1SSam Ravnborg	  VESA-compliant "green" monitors.
2485e279b6c1SSam Ravnborg
2486e279b6c1SSam Ravnborg	  This driver does not support the TI 4000M TravelMate and the ACER
2487e279b6c1SSam Ravnborg	  486/DX4/75 because they don't have compliant BIOSes. Many "green"
2488e279b6c1SSam Ravnborg	  desktop machines also don't have compliant BIOSes, and this driver
2489e279b6c1SSam Ravnborg	  may cause those machines to panic during the boot phase.
2490e279b6c1SSam Ravnborg
2491e279b6c1SSam Ravnborg	  Generally, if you don't have a battery in your machine, there isn't
2492e279b6c1SSam Ravnborg	  much point in using this driver and you should say N. If you get
2493e279b6c1SSam Ravnborg	  random kernel OOPSes or reboots that don't seem to be related to
2494e279b6c1SSam Ravnborg	  anything, try disabling/enabling this option (or disabling/enabling
2495e279b6c1SSam Ravnborg	  APM in your BIOS).
2496e279b6c1SSam Ravnborg
2497e279b6c1SSam Ravnborg	  Some other things you should try when experiencing seemingly random,
2498e279b6c1SSam Ravnborg	  "weird" problems:
2499e279b6c1SSam Ravnborg
2500e279b6c1SSam Ravnborg	  1) make sure that you have enough swap space and that it is
2501e279b6c1SSam Ravnborg	  enabled.
2502e279b6c1SSam Ravnborg	  2) pass the "no-hlt" option to the kernel
2503e279b6c1SSam Ravnborg	  3) switch on floating point emulation in the kernel and pass
2504e279b6c1SSam Ravnborg	  the "no387" option to the kernel
2505e279b6c1SSam Ravnborg	  4) pass the "floppy=nodma" option to the kernel
2506e279b6c1SSam Ravnborg	  5) pass the "mem=4M" option to the kernel (thereby disabling
2507e279b6c1SSam Ravnborg	  all but the first 4 MB of RAM)
2508e279b6c1SSam Ravnborg	  6) make sure that the CPU is not over clocked.
2509e279b6c1SSam Ravnborg	  7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2510e279b6c1SSam Ravnborg	  8) disable the cache from your BIOS settings
2511e279b6c1SSam Ravnborg	  9) install a fan for the video card or exchange video RAM
2512e279b6c1SSam Ravnborg	  10) install a better fan for the CPU
2513e279b6c1SSam Ravnborg	  11) exchange RAM chips
2514e279b6c1SSam Ravnborg	  12) exchange the motherboard.
2515e279b6c1SSam Ravnborg
2516e279b6c1SSam Ravnborg	  To compile this driver as a module, choose M here: the
2517e279b6c1SSam Ravnborg	  module will be called apm.
2518e279b6c1SSam Ravnborg
2519e279b6c1SSam Ravnborgif APM
2520e279b6c1SSam Ravnborg
2521e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND
2522e279b6c1SSam Ravnborg	bool "Ignore USER SUSPEND"
2523a7f7f624SMasahiro Yamada	help
2524e279b6c1SSam Ravnborg	  This option will ignore USER SUSPEND requests. On machines with a
2525e279b6c1SSam Ravnborg	  compliant APM BIOS, you want to say N. However, on the NEC Versa M
2526e279b6c1SSam Ravnborg	  series notebooks, it is necessary to say Y because of a BIOS bug.
2527e279b6c1SSam Ravnborg
2528e279b6c1SSam Ravnborgconfig APM_DO_ENABLE
2529e279b6c1SSam Ravnborg	bool "Enable PM at boot time"
2530a7f7f624SMasahiro Yamada	help
2531e279b6c1SSam Ravnborg	  Enable APM features at boot time. From page 36 of the APM BIOS
2532e279b6c1SSam Ravnborg	  specification: "When disabled, the APM BIOS does not automatically
2533e279b6c1SSam Ravnborg	  power manage devices, enter the Standby State, enter the Suspend
2534e279b6c1SSam Ravnborg	  State, or take power saving steps in response to CPU Idle calls."
2535e279b6c1SSam Ravnborg	  This driver will make CPU Idle calls when Linux is idle (unless this
2536e279b6c1SSam Ravnborg	  feature is turned off -- see "Do CPU IDLE calls", below). This
2537e279b6c1SSam Ravnborg	  should always save battery power, but more complicated APM features
2538e279b6c1SSam Ravnborg	  will be dependent on your BIOS implementation. You may need to turn
2539e279b6c1SSam Ravnborg	  this option off if your computer hangs at boot time when using APM
2540e279b6c1SSam Ravnborg	  support, or if it beeps continuously instead of suspending. Turn
2541e279b6c1SSam Ravnborg	  this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2542e279b6c1SSam Ravnborg	  T400CDT. This is off by default since most machines do fine without
2543e279b6c1SSam Ravnborg	  this feature.
2544e279b6c1SSam Ravnborg
2545e279b6c1SSam Ravnborgconfig APM_CPU_IDLE
2546dd8af076SLen Brown	depends on CPU_IDLE
2547e279b6c1SSam Ravnborg	bool "Make CPU Idle calls when idle"
2548a7f7f624SMasahiro Yamada	help
2549e279b6c1SSam Ravnborg	  Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2550e279b6c1SSam Ravnborg	  On some machines, this can activate improved power savings, such as
2551e279b6c1SSam Ravnborg	  a slowed CPU clock rate, when the machine is idle. These idle calls
2552e279b6c1SSam Ravnborg	  are made after the idle loop has run for some length of time (e.g.,
2553e279b6c1SSam Ravnborg	  333 mS). On some machines, this will cause a hang at boot time or
2554e279b6c1SSam Ravnborg	  whenever the CPU becomes idle. (On machines with more than one CPU,
2555e279b6c1SSam Ravnborg	  this option does nothing.)
2556e279b6c1SSam Ravnborg
2557e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK
2558e279b6c1SSam Ravnborg	bool "Enable console blanking using APM"
2559a7f7f624SMasahiro Yamada	help
2560e279b6c1SSam Ravnborg	  Enable console blanking using the APM. Some laptops can use this to
2561e279b6c1SSam Ravnborg	  turn off the LCD backlight when the screen blanker of the Linux
2562e279b6c1SSam Ravnborg	  virtual console blanks the screen. Note that this is only used by
2563e279b6c1SSam Ravnborg	  the virtual console screen blanker, and won't turn off the backlight
2564e279b6c1SSam Ravnborg	  when using the X Window system. This also doesn't have anything to
2565e279b6c1SSam Ravnborg	  do with your VESA-compliant power-saving monitor. Further, this
2566e279b6c1SSam Ravnborg	  option doesn't work for all laptops -- it might not turn off your
2567e279b6c1SSam Ravnborg	  backlight at all, or it might print a lot of errors to the console,
2568e279b6c1SSam Ravnborg	  especially if you are using gpm.
2569e279b6c1SSam Ravnborg
2570e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS
2571e279b6c1SSam Ravnborg	bool "Allow interrupts during APM BIOS calls"
2572a7f7f624SMasahiro Yamada	help
2573e279b6c1SSam Ravnborg	  Normally we disable external interrupts while we are making calls to
2574e279b6c1SSam Ravnborg	  the APM BIOS as a measure to lessen the effects of a badly behaving
2575e279b6c1SSam Ravnborg	  BIOS implementation.  The BIOS should reenable interrupts if it
2576e279b6c1SSam Ravnborg	  needs to.  Unfortunately, some BIOSes do not -- especially those in
2577e279b6c1SSam Ravnborg	  many of the newer IBM Thinkpads.  If you experience hangs when you
2578e279b6c1SSam Ravnborg	  suspend, try setting this to Y.  Otherwise, say N.
2579e279b6c1SSam Ravnborg
2580e279b6c1SSam Ravnborgendif # APM
2581e279b6c1SSam Ravnborg
2582bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig"
2583e279b6c1SSam Ravnborg
2584e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig"
2585e279b6c1SSam Ravnborg
258627471fdbSAndy Henroidsource "drivers/idle/Kconfig"
258727471fdbSAndy Henroid
2588e279b6c1SSam Ravnborgendmenu
2589e279b6c1SSam Ravnborg
2590e279b6c1SSam Ravnborg
2591e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)"
2592e279b6c1SSam Ravnborg
2593e279b6c1SSam Ravnborgchoice
2594e279b6c1SSam Ravnborg	prompt "PCI access mode"
2595efefa6f6SIngo Molnar	depends on X86_32 && PCI
2596e279b6c1SSam Ravnborg	default PCI_GOANY
2597a7f7f624SMasahiro Yamada	help
2598e279b6c1SSam Ravnborg	  On PCI systems, the BIOS can be used to detect the PCI devices and
2599e279b6c1SSam Ravnborg	  determine their configuration. However, some old PCI motherboards
2600e279b6c1SSam Ravnborg	  have BIOS bugs and may crash if this is done. Also, some embedded
2601e279b6c1SSam Ravnborg	  PCI-based systems don't have any BIOS at all. Linux can also try to
2602e279b6c1SSam Ravnborg	  detect the PCI hardware directly without using the BIOS.
2603e279b6c1SSam Ravnborg
2604e279b6c1SSam Ravnborg	  With this option, you can specify how Linux should detect the
2605e279b6c1SSam Ravnborg	  PCI devices. If you choose "BIOS", the BIOS will be used,
2606e279b6c1SSam Ravnborg	  if you choose "Direct", the BIOS won't be used, and if you
2607e279b6c1SSam Ravnborg	  choose "MMConfig", then PCI Express MMCONFIG will be used.
2608e279b6c1SSam Ravnborg	  If you choose "Any", the kernel will try MMCONFIG, then the
2609e279b6c1SSam Ravnborg	  direct access method and falls back to the BIOS if that doesn't
2610e279b6c1SSam Ravnborg	  work. If unsure, go with the default, which is "Any".
2611e279b6c1SSam Ravnborg
2612e279b6c1SSam Ravnborgconfig PCI_GOBIOS
2613e279b6c1SSam Ravnborg	bool "BIOS"
2614e279b6c1SSam Ravnborg
2615e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG
2616e279b6c1SSam Ravnborg	bool "MMConfig"
2617e279b6c1SSam Ravnborg
2618e279b6c1SSam Ravnborgconfig PCI_GODIRECT
2619e279b6c1SSam Ravnborg	bool "Direct"
2620e279b6c1SSam Ravnborg
26213ef0e1f8SAndres Salomonconfig PCI_GOOLPC
262276fb6570SDaniel Drake	bool "OLPC XO-1"
26233ef0e1f8SAndres Salomon	depends on OLPC
26243ef0e1f8SAndres Salomon
26252bdd1b03SAndres Salomonconfig PCI_GOANY
26262bdd1b03SAndres Salomon	bool "Any"
26272bdd1b03SAndres Salomon
2628e279b6c1SSam Ravnborgendchoice
2629e279b6c1SSam Ravnborg
2630e279b6c1SSam Ravnborgconfig PCI_BIOS
26313c2362e6SHarvey Harrison	def_bool y
2632efefa6f6SIngo Molnar	depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2633e279b6c1SSam Ravnborg
2634e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2635e279b6c1SSam Ravnborgconfig PCI_DIRECT
26363c2362e6SHarvey Harrison	def_bool y
26370aba496fSShaohua Li	depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2638e279b6c1SSam Ravnborg
2639e279b6c1SSam Ravnborgconfig PCI_MMCONFIG
2640b45c9f36SJan Kiszka	bool "Support mmconfig PCI config space access" if X86_64
2641b45c9f36SJan Kiszka	default y
26424590d98fSAndy Shevchenko	depends on PCI && (ACPI || JAILHOUSE_GUEST)
2643b45c9f36SJan Kiszka	depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
2644e279b6c1SSam Ravnborg
26453ef0e1f8SAndres Salomonconfig PCI_OLPC
26462bdd1b03SAndres Salomon	def_bool y
26472bdd1b03SAndres Salomon	depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
26483ef0e1f8SAndres Salomon
2649b5401a96SAlex Nixonconfig PCI_XEN
2650b5401a96SAlex Nixon	def_bool y
2651b5401a96SAlex Nixon	depends on PCI && XEN
2652b5401a96SAlex Nixon
26538364e1f8SJan Kiszkaconfig MMCONF_FAM10H
26548364e1f8SJan Kiszka	def_bool y
26558364e1f8SJan Kiszka	depends on X86_64 && PCI_MMCONFIG && ACPI
2656e279b6c1SSam Ravnborg
26573f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK
26586a108a14SDavid Rientjes	bool "Read CNB20LE Host Bridge Windows" if EXPERT
26596ea30386SKees Cook	depends on PCI
26603f6ea84aSIra W. Snyder	help
26613f6ea84aSIra W. Snyder	  Read the PCI windows out of the CNB20LE host bridge. This allows
26623f6ea84aSIra W. Snyder	  PCI hotplug to work on systems with the CNB20LE chipset which do
26633f6ea84aSIra W. Snyder	  not have ACPI.
26643f6ea84aSIra W. Snyder
266564a5fed6SBjorn Helgaas	  There's no public spec for this chipset, and this functionality
266664a5fed6SBjorn Helgaas	  is known to be incomplete.
266764a5fed6SBjorn Helgaas
266864a5fed6SBjorn Helgaas	  You should say N unless you know you need this.
266964a5fed6SBjorn Helgaas
26703a495511SWilliam Breathitt Grayconfig ISA_BUS
267117a2a129SWilliam Breathitt Gray	bool "ISA bus support on modern systems" if EXPERT
26723a495511SWilliam Breathitt Gray	help
267317a2a129SWilliam Breathitt Gray	  Expose ISA bus device drivers and options available for selection and
267417a2a129SWilliam Breathitt Gray	  configuration. Enable this option if your target machine has an ISA
267517a2a129SWilliam Breathitt Gray	  bus. ISA is an older system, displaced by PCI and newer bus
267617a2a129SWilliam Breathitt Gray	  architectures -- if your target machine is modern, it probably does
267717a2a129SWilliam Breathitt Gray	  not have an ISA bus.
26783a495511SWilliam Breathitt Gray
26793a495511SWilliam Breathitt Gray	  If unsure, say N.
26803a495511SWilliam Breathitt Gray
26811c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA.
2682e279b6c1SSam Ravnborgconfig ISA_DMA_API
26831c00f016SDavid Rientjes	bool "ISA-style DMA support" if (X86_64 && EXPERT)
26841c00f016SDavid Rientjes	default y
26851c00f016SDavid Rientjes	help
26861c00f016SDavid Rientjes	  Enables ISA-style DMA support for devices requiring such controllers.
26871c00f016SDavid Rientjes	  If unsure, say Y.
2688e279b6c1SSam Ravnborg
268951e68d05SLinus Torvaldsif X86_32
269051e68d05SLinus Torvalds
2691e279b6c1SSam Ravnborgconfig ISA
2692e279b6c1SSam Ravnborg	bool "ISA support"
2693a7f7f624SMasahiro Yamada	help
2694e279b6c1SSam Ravnborg	  Find out whether you have ISA slots on your motherboard.  ISA is the
2695e279b6c1SSam Ravnborg	  name of a bus system, i.e. the way the CPU talks to the other stuff
2696e279b6c1SSam Ravnborg	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
2697e279b6c1SSam Ravnborg	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2698e279b6c1SSam Ravnborg	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
2699e279b6c1SSam Ravnborg
2700e279b6c1SSam Ravnborgconfig SCx200
2701e279b6c1SSam Ravnborg	tristate "NatSemi SCx200 support"
2702a7f7f624SMasahiro Yamada	help
2703e279b6c1SSam Ravnborg	  This provides basic support for National Semiconductor's
2704e279b6c1SSam Ravnborg	  (now AMD's) Geode processors.  The driver probes for the
2705e279b6c1SSam Ravnborg	  PCI-IDs of several on-chip devices, so its a good dependency
2706e279b6c1SSam Ravnborg	  for other scx200_* drivers.
2707e279b6c1SSam Ravnborg
2708e279b6c1SSam Ravnborg	  If compiled as a module, the driver is named scx200.
2709e279b6c1SSam Ravnborg
2710e279b6c1SSam Ravnborgconfig SCx200HR_TIMER
2711e279b6c1SSam Ravnborg	tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2712592913ecSJohn Stultz	depends on SCx200
2713e279b6c1SSam Ravnborg	default y
2714a7f7f624SMasahiro Yamada	help
2715e279b6c1SSam Ravnborg	  This driver provides a clocksource built upon the on-chip
2716e279b6c1SSam Ravnborg	  27MHz high-resolution timer.  Its also a workaround for
2717e279b6c1SSam Ravnborg	  NSC Geode SC-1100's buggy TSC, which loses time when the
2718e279b6c1SSam Ravnborg	  processor goes idle (as is done by the scheduler).  The
2719e279b6c1SSam Ravnborg	  other workaround is idle=poll boot option.
2720e279b6c1SSam Ravnborg
27213ef0e1f8SAndres Salomonconfig OLPC
27223ef0e1f8SAndres Salomon	bool "One Laptop Per Child support"
272354008979SThomas Gleixner	depends on !X86_PAE
27243c554946SAndres Salomon	select GPIOLIB
2725dc3119e7SThomas Gleixner	select OF
272645bb1674SDaniel Drake	select OF_PROMTREE
2727b4e51854SGrant Likely	select IRQ_DOMAIN
27280c3d931bSLubomir Rintel	select OLPC_EC
2729a7f7f624SMasahiro Yamada	help
27303ef0e1f8SAndres Salomon	  Add support for detecting the unique features of the OLPC
27313ef0e1f8SAndres Salomon	  XO hardware.
27323ef0e1f8SAndres Salomon
2733a3128588SDaniel Drakeconfig OLPC_XO1_PM
2734a3128588SDaniel Drake	bool "OLPC XO-1 Power Management"
2735fa112cf1SBorislav Petkov	depends on OLPC && MFD_CS5535=y && PM_SLEEP
2736a7f7f624SMasahiro Yamada	help
273797c4cb71SDaniel Drake	  Add support for poweroff and suspend of the OLPC XO-1 laptop.
2738bf1ebf00SDaniel Drake
2739cfee9597SDaniel Drakeconfig OLPC_XO1_RTC
2740cfee9597SDaniel Drake	bool "OLPC XO-1 Real Time Clock"
2741cfee9597SDaniel Drake	depends on OLPC_XO1_PM && RTC_DRV_CMOS
2742a7f7f624SMasahiro Yamada	help
2743cfee9597SDaniel Drake	  Add support for the XO-1 real time clock, which can be used as a
2744cfee9597SDaniel Drake	  programmable wakeup source.
2745cfee9597SDaniel Drake
27467feda8e9SDaniel Drakeconfig OLPC_XO1_SCI
27477feda8e9SDaniel Drake	bool "OLPC XO-1 SCI extras"
274892e830f2SArnd Bergmann	depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
2749ed8e47feSRandy Dunlap	depends on INPUT=y
2750d8d01a63SDaniel Drake	select POWER_SUPPLY
2751a7f7f624SMasahiro Yamada	help
27527feda8e9SDaniel Drake	  Add support for SCI-based features of the OLPC XO-1 laptop:
27537bc74b3dSDaniel Drake	   - EC-driven system wakeups
27547feda8e9SDaniel Drake	   - Power button
27557bc74b3dSDaniel Drake	   - Ebook switch
27562cf2baeaSDaniel Drake	   - Lid switch
2757e1040ac6SDaniel Drake	   - AC adapter status updates
2758e1040ac6SDaniel Drake	   - Battery status updates
27597feda8e9SDaniel Drake
2760a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI
2761a0f30f59SDaniel Drake	bool "OLPC XO-1.5 SCI extras"
2762d8d01a63SDaniel Drake	depends on OLPC && ACPI
2763d8d01a63SDaniel Drake	select POWER_SUPPLY
2764a7f7f624SMasahiro Yamada	help
2765a0f30f59SDaniel Drake	  Add support for SCI-based features of the OLPC XO-1.5 laptop:
2766a0f30f59SDaniel Drake	   - EC-driven system wakeups
2767a0f30f59SDaniel Drake	   - AC adapter status updates
2768a0f30f59SDaniel Drake	   - Battery status updates
2769e279b6c1SSam Ravnborg
2770d4f3e350SEd Wildgooseconfig ALIX
2771d4f3e350SEd Wildgoose	bool "PCEngines ALIX System Support (LED setup)"
2772d4f3e350SEd Wildgoose	select GPIOLIB
2773a7f7f624SMasahiro Yamada	help
2774d4f3e350SEd Wildgoose	  This option enables system support for the PCEngines ALIX.
2775d4f3e350SEd Wildgoose	  At present this just sets up LEDs for GPIO control on
2776d4f3e350SEd Wildgoose	  ALIX2/3/6 boards.  However, other system specific setup should
2777d4f3e350SEd Wildgoose	  get added here.
2778d4f3e350SEd Wildgoose
2779d4f3e350SEd Wildgoose	  Note: You must still enable the drivers for GPIO and LED support
2780d4f3e350SEd Wildgoose	  (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2781d4f3e350SEd Wildgoose
2782d4f3e350SEd Wildgoose	  Note: You have to set alix.force=1 for boards with Award BIOS.
2783d4f3e350SEd Wildgoose
2784da4e3302SPhilip Prindevilleconfig NET5501
2785da4e3302SPhilip Prindeville	bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2786da4e3302SPhilip Prindeville	select GPIOLIB
2787a7f7f624SMasahiro Yamada	help
2788da4e3302SPhilip Prindeville	  This option enables system support for the Soekris Engineering net5501.
2789da4e3302SPhilip Prindeville
27903197059aSPhilip A. Prindevilleconfig GEOS
27913197059aSPhilip A. Prindeville	bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
27923197059aSPhilip A. Prindeville	select GPIOLIB
27933197059aSPhilip A. Prindeville	depends on DMI
2794a7f7f624SMasahiro Yamada	help
27953197059aSPhilip A. Prindeville	  This option enables system support for the Traverse Technologies GEOS.
27963197059aSPhilip A. Prindeville
27977d029125SVivien Didelotconfig TS5500
27987d029125SVivien Didelot	bool "Technologic Systems TS-5500 platform support"
27997d029125SVivien Didelot	depends on MELAN
28007d029125SVivien Didelot	select CHECK_SIGNATURE
28017d029125SVivien Didelot	select NEW_LEDS
28027d029125SVivien Didelot	select LEDS_CLASS
2803a7f7f624SMasahiro Yamada	help
28047d029125SVivien Didelot	  This option enables system support for the Technologic Systems TS-5500.
28057d029125SVivien Didelot
2806e279b6c1SSam Ravnborgendif # X86_32
2807e279b6c1SSam Ravnborg
280823ac4ae8SAndreas Herrmannconfig AMD_NB
2809e279b6c1SSam Ravnborg	def_bool y
28100e152cd7SBorislav Petkov	depends on CPU_SUP_AMD && PCI
2811e279b6c1SSam Ravnborg
2812e279b6c1SSam Ravnborgendmenu
2813e279b6c1SSam Ravnborg
2814e279b6c1SSam Ravnborg
28151572497cSChristoph Hellwigmenu "Binary Emulations"
2816e279b6c1SSam Ravnborg
2817e279b6c1SSam Ravnborgconfig IA32_EMULATION
2818e279b6c1SSam Ravnborg	bool "IA32 Emulation"
2819e279b6c1SSam Ravnborg	depends on X86_64
282039f88911SIngo Molnar	select ARCH_WANT_OLD_COMPAT_IPC
2821d1603990SRandy Dunlap	select BINFMT_ELF
282239f88911SIngo Molnar	select COMPAT_OLD_SIGACTION
2823a7f7f624SMasahiro Yamada	help
28245fd92e65SH. J. Lu	  Include code to run legacy 32-bit programs under a
28255fd92e65SH. J. Lu	  64-bit kernel. You should likely turn this on, unless you're
28265fd92e65SH. J. Lu	  100% sure that you don't have any 32-bit programs left.
2827e279b6c1SSam Ravnborg
2828e279b6c1SSam Ravnborgconfig IA32_AOUT
2829e279b6c1SSam Ravnborg	tristate "IA32 a.out support"
28306b213e1bSDavid Woodhouse	depends on IA32_EMULATION
2831eac61655SBorislav Petkov	depends on BROKEN
2832a7f7f624SMasahiro Yamada	help
2833e279b6c1SSam Ravnborg	  Support old a.out binaries in the 32bit emulation.
2834e279b6c1SSam Ravnborg
28350bf62763SH. Peter Anvinconfig X86_X32
28366ea30386SKees Cook	bool "x32 ABI for 64-bit mode"
28379b54050bSBrian Gerst	depends on X86_64
2838a7f7f624SMasahiro Yamada	help
28395fd92e65SH. J. Lu	  Include code to run binaries for the x32 native 32-bit ABI
28405fd92e65SH. J. Lu	  for 64-bit processors.  An x32 process gets access to the
28415fd92e65SH. J. Lu	  full 64-bit register file and wide data path while leaving
28425fd92e65SH. J. Lu	  pointers at 32 bits for smaller memory footprint.
28435fd92e65SH. J. Lu
28445fd92e65SH. J. Lu	  You will need a recent binutils (2.22 or later) with
28455fd92e65SH. J. Lu	  elf32_x86_64 support enabled to compile a kernel with this
28465fd92e65SH. J. Lu	  option set.
28475fd92e65SH. J. Lu
2848953fee1dSIngo Molnarconfig COMPAT_32
2849953fee1dSIngo Molnar	def_bool y
2850953fee1dSIngo Molnar	depends on IA32_EMULATION || X86_32
2851953fee1dSIngo Molnar	select HAVE_UID16
2852953fee1dSIngo Molnar	select OLD_SIGSUSPEND3
2853953fee1dSIngo Molnar
2854e279b6c1SSam Ravnborgconfig COMPAT
28553c2362e6SHarvey Harrison	def_bool y
28560bf62763SH. Peter Anvin	depends on IA32_EMULATION || X86_X32
2857e279b6c1SSam Ravnborg
28583120e25eSJan Beulichif COMPAT
2859e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT
28603120e25eSJan Beulich	def_bool y
2861e279b6c1SSam Ravnborg
2862e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT
28633c2362e6SHarvey Harrison	def_bool y
28643120e25eSJan Beulich	depends on SYSVIPC
28653120e25eSJan Beulichendif
2866ee009e4aSDavid Howells
2867e279b6c1SSam Ravnborgendmenu
2868e279b6c1SSam Ravnborg
2869e279b6c1SSam Ravnborg
2870e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP
2871e5beae16SKeith Packard	def_bool y
2872e5beae16SKeith Packard	depends on X86_32
2873e5beae16SKeith Packard
2874edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig"
28755e8ebd84SJason A. Donenfeld
28765e8ebd84SJason A. Donenfeldsource "arch/x86/Kconfig.assembler"
2877