xref: /linux/arch/x86/Kconfig (revision 04d5ea46a15149a12f79c686b6a1ffc9c3233272)
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
300bff0aaeSSuren Baghdasaryan	select ARCH_SUPPORTS_PER_VMA_LOCK
31d94e0685SIngo Molnar	select ARCH_USE_CMPXCHG_LOCKREF
32d94e0685SIngo Molnar	select HAVE_ARCH_SOFT_DIRTY
33d94e0685SIngo Molnar	select MODULES_USE_ELF_RELA
34f616ab59SChristoph Hellwig	select NEED_DMA_MAP_STATE
3509230cbcSChristoph Hellwig	select SWIOTLB
367facdc42SAl Viro	select ARCH_HAS_ELFCORE_COMPAT
3763703f37SKefeng Wang	select ZONE_DMA32
381032c0baSSam Ravnborg
39518049d9SSteven Rostedt (VMware)config FORCE_DYNAMIC_FTRACE
40518049d9SSteven Rostedt (VMware)	def_bool y
41518049d9SSteven Rostedt (VMware)	depends on X86_32
42518049d9SSteven Rostedt (VMware)	depends on FUNCTION_TRACER
43518049d9SSteven Rostedt (VMware)	select DYNAMIC_FTRACE
44518049d9SSteven Rostedt (VMware)	help
45518049d9SSteven Rostedt (VMware)	  We keep the static function tracing (!DYNAMIC_FTRACE) around
46518049d9SSteven Rostedt (VMware)	  in order to test the non static function tracing in the
47518049d9SSteven Rostedt (VMware)	  generic code, as other architectures still use it. But we
48518049d9SSteven Rostedt (VMware)	  only need to keep it around for x86_64. No need to keep it
49518049d9SSteven Rostedt (VMware)	  for x86_32. For x86_32, force DYNAMIC_FTRACE.
50d94e0685SIngo Molnar#
51d94e0685SIngo Molnar# Arch settings
52d94e0685SIngo Molnar#
53d94e0685SIngo Molnar# ( Note that options that are marked 'if X86_64' could in principle be
54d94e0685SIngo Molnar#   ported to 32-bit as well. )
55d94e0685SIngo Molnar#
568d5fffb9SSam Ravnborgconfig X86
573c2362e6SHarvey Harrison	def_bool y
58c763ea26SIngo Molnar	#
59c763ea26SIngo Molnar	# Note: keep this list sorted alphabetically
60c763ea26SIngo Molnar	#
616471b825SIngo Molnar	select ACPI_LEGACY_TABLES_LOOKUP	if ACPI
626e0a0ea1SGraeme Gregory	select ACPI_SYSTEM_POWER_STATES_SUPPORT	if ACPI
63942fa985SYury Norov	select ARCH_32BIT_OFF_T			if X86_32
642a21ad57SThomas Gleixner	select ARCH_CLOCKSOURCE_INIT
651f6d3a8fSMasami Hiramatsu	select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
661e866974SAnshuman Khandual	select ARCH_ENABLE_HUGEPAGE_MIGRATION if X86_64 && HUGETLB_PAGE && MIGRATION
675c11f00bSDavid Hildenbrand	select ARCH_ENABLE_MEMORY_HOTPLUG if X86_64
6891024b3cSAnshuman Khandual	select ARCH_ENABLE_MEMORY_HOTREMOVE if MEMORY_HOTPLUG
69cebc774fSAnshuman Khandual	select ARCH_ENABLE_SPLIT_PMD_PTLOCK if (PGTABLE_LEVELS > 2) && (X86_64 || X86_PAE)
701e866974SAnshuman Khandual	select ARCH_ENABLE_THP_MIGRATION if X86_64 && TRANSPARENT_HUGEPAGE
7191dda51aSAleksey Makarov	select ARCH_HAS_ACPI_TABLE_UPGRADE	if ACPI
72c2280be8SAnshuman Khandual	select ARCH_HAS_CACHE_LINE_SIZE
731156b441SDavidlohr Bueso	select ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION
747c7077a7SThomas Gleixner	select ARCH_HAS_CPU_FINALIZE_INIT
752792d84eSKees Cook	select ARCH_HAS_CURRENT_STACK_POINTER
76fa5b6ec9SLaura Abbott	select ARCH_HAS_DEBUG_VIRTUAL
77399145f9SAnshuman Khandual	select ARCH_HAS_DEBUG_VM_PGTABLE	if !X86_PAE
7821266be9SDan Williams	select ARCH_HAS_DEVMEM_IS_ALLOWED
79b1a57bbfSDouglas Anderson	select ARCH_HAS_EARLY_DEBUG		if KGDB
806471b825SIngo Molnar	select ARCH_HAS_ELF_RANDOMIZE
8172d93104SLinus Torvalds	select ARCH_HAS_FAST_MULTIPLIER
826974f0c4SDaniel Micay	select ARCH_HAS_FORTIFY_SOURCE
83957e3facSRiku Voipio	select ARCH_HAS_GCOV_PROFILE_ALL
84bece04b5SMarco Elver	select ARCH_HAS_KCOV			if X86_64
850c9c1d56SThiago Jung Bauermann	select ARCH_HAS_MEM_ENCRYPT
8610bcc80eSMathieu Desnoyers	select ARCH_HAS_MEMBARRIER_SYNC_CORE
8749f88c70SPaul E. McKenney	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
880ebeea8cSDaniel Borkmann	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
89c763ea26SIngo Molnar	select ARCH_HAS_PMEM_API		if X86_64
9017596731SRobin Murphy	select ARCH_HAS_PTE_DEVMAP		if X86_64
913010a5eaSLaurent Dufour	select ARCH_HAS_PTE_SPECIAL
92eed9a328SYu Zhao	select ARCH_HAS_NONLEAF_PMD_YOUNG	if PGTABLE_LEVELS > 2
930aed55afSDan Williams	select ARCH_HAS_UACCESS_FLUSHCACHE	if X86_64
94ec6347bbSDan Williams	select ARCH_HAS_COPY_MC			if X86_64
95d2852a22SDaniel Borkmann	select ARCH_HAS_SET_MEMORY
96d253ca0cSRick Edgecombe	select ARCH_HAS_SET_DIRECT_MAP
97ad21fc4fSLaura Abbott	select ARCH_HAS_STRICT_KERNEL_RWX
98ad21fc4fSLaura Abbott	select ARCH_HAS_STRICT_MODULE_RWX
99ac1ab12aSMathieu Desnoyers	select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
10025c619e5SBrian Gerst	select ARCH_HAS_SYSCALL_WRAPPER
101c6d30853SAndrey Ryabinin	select ARCH_HAS_UBSAN_SANITIZE_ALL
1027e01ccb4SZong Li	select ARCH_HAS_DEBUG_WX
10363703f37SKefeng Wang	select ARCH_HAS_ZONE_DMA_SET if EXPERT
1046471b825SIngo Molnar	select ARCH_HAVE_NMI_SAFE_CMPXCHG
105*04d5ea46SAneesh Kumar K.V	select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
1066471b825SIngo Molnar	select ARCH_MIGHT_HAVE_ACPI_PDC		if ACPI
10777fbbc81SMark Salter	select ARCH_MIGHT_HAVE_PC_PARPORT
1085e2c18c0SMark Salter	select ARCH_MIGHT_HAVE_PC_SERIO
1093599fe12SThomas Gleixner	select ARCH_STACKWALK
1102c870e61SArnd Bergmann	select ARCH_SUPPORTS_ACPI
1116471b825SIngo Molnar	select ARCH_SUPPORTS_ATOMIC_RMW
1125d6ad668SMike Rapoport	select ARCH_SUPPORTS_DEBUG_PAGEALLOC
113d283d422SPasha Tatashin	select ARCH_SUPPORTS_PAGE_TABLE_CHECK	if X86_64
1146471b825SIngo Molnar	select ARCH_SUPPORTS_NUMA_BALANCING	if X86_64
11514df3267SThomas Gleixner	select ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP	if NR_CPUS <= 4096
1163c516f89SSami Tolvanen	select ARCH_SUPPORTS_CFI_CLANG		if X86_64
1173c516f89SSami Tolvanen	select ARCH_USES_CFI_TRAPS		if X86_64 && CFI_CLANG
118583bfd48SNathan Chancellor	select ARCH_SUPPORTS_LTO_CLANG
119583bfd48SNathan Chancellor	select ARCH_SUPPORTS_LTO_CLANG_THIN
1206471b825SIngo Molnar	select ARCH_USE_BUILTIN_BSWAP
121dce44566SAnshuman Khandual	select ARCH_USE_MEMTEST
1226471b825SIngo Molnar	select ARCH_USE_QUEUED_RWLOCKS
1236471b825SIngo Molnar	select ARCH_USE_QUEUED_SPINLOCKS
1242ce0d7f9SMark Brown	select ARCH_USE_SYM_ANNOTATIONS
125ce4a4e56SAndy Lutomirski	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
12681c22041SDaniel Borkmann	select ARCH_WANT_DEFAULT_BPF_JIT	if X86_64
127c763ea26SIngo Molnar	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
12851c2ee6dSNick Desaulniers	select ARCH_WANTS_NO_INSTR
12907431506SAnshuman Khandual	select ARCH_WANT_GENERAL_HUGETLB
1303876d4a3SAlexandre Ghiti	select ARCH_WANT_HUGE_PMD_SHARE
13159612b24SNathan Chancellor	select ARCH_WANT_LD_ORPHAN_WARN
1320b6f1582SAneesh Kumar K.V	select ARCH_WANT_OPTIMIZE_DAX_VMEMMAP	if X86_64
1330b6f1582SAneesh Kumar K.V	select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP	if X86_64
13438d8b4e6SHuang Ying	select ARCH_WANTS_THP_SWAP		if X86_64
135b5f06f64SBalbir Singh	select ARCH_HAS_PARANOID_L1D_FLUSH
13610916706SShile Zhang	select BUILDTIME_TABLE_SORT
1376471b825SIngo Molnar	select CLKEVT_I8253
1386471b825SIngo Molnar	select CLOCKSOURCE_VALIDATE_LAST_CYCLE
1396471b825SIngo Molnar	select CLOCKSOURCE_WATCHDOG
1407cf8f44aSAlexander Potapenko	# Word-size accesses may read uninitialized data past the trailing \0
1417cf8f44aSAlexander Potapenko	# in strings and cause false KMSAN reports.
1427cf8f44aSAlexander Potapenko	select DCACHE_WORD_ACCESS		if !KMSAN
1433aac3ebeSThomas Gleixner	select DYNAMIC_SIGFRAME
14445471cd9SLinus Torvalds	select EDAC_ATOMIC_SCRUB
14545471cd9SLinus Torvalds	select EDAC_SUPPORT
1466471b825SIngo Molnar	select GENERIC_CLOCKEVENTS_BROADCAST	if X86_64 || (X86_32 && X86_LOCAL_APIC)
1476471b825SIngo Molnar	select GENERIC_CLOCKEVENTS_MIN_ADJUST
1486471b825SIngo Molnar	select GENERIC_CMOS_UPDATE
1496471b825SIngo Molnar	select GENERIC_CPU_AUTOPROBE
15061dc0f55SThomas Gleixner	select GENERIC_CPU_VULNERABILITIES
1516471b825SIngo Molnar	select GENERIC_EARLY_IOREMAP
15227d6b4d1SThomas Gleixner	select GENERIC_ENTRY
1536471b825SIngo Molnar	select GENERIC_IOMAP
154c7d6c9ddSThomas Gleixner	select GENERIC_IRQ_EFFECTIVE_AFF_MASK	if SMP
1550fa115daSThomas Gleixner	select GENERIC_IRQ_MATRIX_ALLOCATOR	if X86_LOCAL_APIC
156ad7a929fSThomas Gleixner	select GENERIC_IRQ_MIGRATION		if SMP
1576471b825SIngo Molnar	select GENERIC_IRQ_PROBE
158c201c917SThomas Gleixner	select GENERIC_IRQ_RESERVATION_MODE
1596471b825SIngo Molnar	select GENERIC_IRQ_SHOW
1606471b825SIngo Molnar	select GENERIC_PENDING_IRQ		if SMP
1612ae27137SSteven Price	select GENERIC_PTDUMP
1626471b825SIngo Molnar	select GENERIC_SMP_IDLE_THREAD
1636471b825SIngo Molnar	select GENERIC_TIME_VSYSCALL
1647ac87074SVincenzo Frascino	select GENERIC_GETTIMEOFDAY
165550a77a7SDmitry Safonov	select GENERIC_VDSO_TIME_NS
1666ca297d4SPeter Zijlstra	select GUP_GET_PXX_LOW_HIGH		if X86_PAE
16717e5888eSHans de Goede	select HARDIRQS_SW_RESEND
1687edaeb68SThomas Gleixner	select HARDLOCKUP_CHECK_TIMESTAMP	if X86_64
169fcbfe812SNiklas Schnelle	select HAS_IOPORT
1706471b825SIngo Molnar	select HAVE_ACPI_APEI			if ACPI
1716471b825SIngo Molnar	select HAVE_ACPI_APEI_NMI		if ACPI
1726471b825SIngo Molnar	select HAVE_ALIGNED_STRUCT_PAGE		if SLUB
1736471b825SIngo Molnar	select HAVE_ARCH_AUDITSYSCALL
1746471b825SIngo Molnar	select HAVE_ARCH_HUGE_VMAP		if X86_64 || X86_PAE
175eed1fceeSSong Liu	select HAVE_ARCH_HUGE_VMALLOC		if X86_64
1766471b825SIngo Molnar	select HAVE_ARCH_JUMP_LABEL
177b34006c4SArd Biesheuvel	select HAVE_ARCH_JUMP_LABEL_RELATIVE
178d17a1d97SAndrey Ryabinin	select HAVE_ARCH_KASAN			if X86_64
1790609ae01SDaniel Axtens	select HAVE_ARCH_KASAN_VMALLOC		if X86_64
1801dc0da6eSAlexander Potapenko	select HAVE_ARCH_KFENCE
1814ca8cc8dSAlexander Potapenko	select HAVE_ARCH_KMSAN			if X86_64
1826471b825SIngo Molnar	select HAVE_ARCH_KGDB
1839e08f57dSDaniel Cashman	select HAVE_ARCH_MMAP_RND_BITS		if MMU
1849e08f57dSDaniel Cashman	select HAVE_ARCH_MMAP_RND_COMPAT_BITS	if MMU && COMPAT
1851b028f78SDmitry Safonov	select HAVE_ARCH_COMPAT_MMAP_BASES	if MMU && COMPAT
186271ca788SArd Biesheuvel	select HAVE_ARCH_PREL32_RELOCATIONS
1876471b825SIngo Molnar	select HAVE_ARCH_SECCOMP_FILTER
188f7d83c1cSKees Cook	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
189afaef01cSAlexander Popov	select HAVE_ARCH_STACKLEAK
1906471b825SIngo Molnar	select HAVE_ARCH_TRACEHOOK
1916471b825SIngo Molnar	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
192a00cc7d9SMatthew Wilcox	select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
193b64d8d1eSPeter Xu	select HAVE_ARCH_USERFAULTFD_WP         if X86_64 && USERFAULTFD
1947677f7fdSAxel Rasmussen	select HAVE_ARCH_USERFAULTFD_MINOR	if X86_64 && USERFAULTFD
195e37e43a4SAndy Lutomirski	select HAVE_ARCH_VMAP_STACK		if X86_64
196fe950f60SKees Cook	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
197c763ea26SIngo Molnar	select HAVE_ARCH_WITHIN_STACK_FRAMES
1982ff2b7ecSMasahiro Yamada	select HAVE_ASM_MODVERSIONS
1996471b825SIngo Molnar	select HAVE_CMPXCHG_DOUBLE
2006471b825SIngo Molnar	select HAVE_CMPXCHG_LOCAL
20124a9c541SFrederic Weisbecker	select HAVE_CONTEXT_TRACKING_USER		if X86_64
20224a9c541SFrederic Weisbecker	select HAVE_CONTEXT_TRACKING_USER_OFFSTACK	if HAVE_CONTEXT_TRACKING_USER
2036471b825SIngo Molnar	select HAVE_C_RECORDMCOUNT
20403f16cd0SJosh Poimboeuf	select HAVE_OBJTOOL_MCOUNT		if HAVE_OBJTOOL
205280981d6SSathvika Vasireddy	select HAVE_OBJTOOL_NOP_MCOUNT		if HAVE_OBJTOOL_MCOUNT
2064ed308c4SSteven Rostedt (Google)	select HAVE_BUILDTIME_MCOUNT_SORT
2076471b825SIngo Molnar	select HAVE_DEBUG_KMEMLEAK
2089c5a3621SAkinobu Mita	select HAVE_DMA_CONTIGUOUS
209677aa9f7SSteven Rostedt	select HAVE_DYNAMIC_FTRACE
21006aeaaeaSMasami Hiramatsu	select HAVE_DYNAMIC_FTRACE_WITH_REGS
21102a474caSSteven Rostedt (VMware)	select HAVE_DYNAMIC_FTRACE_WITH_ARGS	if X86_64
212562955feSSteven Rostedt (VMware)	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
213c316eb44SHeiko Carstens	select HAVE_SAMPLE_FTRACE_DIRECT	if X86_64
214503e4510SHeiko Carstens	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI	if X86_64
21503f5781bSWang YanQing	select HAVE_EBPF_JIT
21658340a07SJohannes Berg	select HAVE_EFFICIENT_UNALIGNED_ACCESS
2176630a8e5SChristoph Hellwig	select HAVE_EISA
2185f56a5dfSJiri Slaby	select HAVE_EXIT_THREAD
21967a929e0SChristoph Hellwig	select HAVE_FAST_GUP
220644e0e8dSSteven Rostedt (VMware)	select HAVE_FENTRY			if X86_64 || DYNAMIC_FTRACE
2216471b825SIngo Molnar	select HAVE_FTRACE_MCOUNT_RECORD
222d938ba17SDonglin Peng	select HAVE_FUNCTION_GRAPH_RETVAL	if HAVE_FUNCTION_GRAPH_TRACER
2234a30e4c9SSteven Rostedt (VMware)	select HAVE_FUNCTION_GRAPH_TRACER	if X86_32 || (X86_64 && DYNAMIC_FTRACE)
2246471b825SIngo Molnar	select HAVE_FUNCTION_TRACER
2256b90bd4bSEmese Revfy	select HAVE_GCC_PLUGINS
2260067f129SK.Prasad	select HAVE_HW_BREAKPOINT
2276471b825SIngo Molnar	select HAVE_IOREMAP_PROT
228624db9eaSThomas Gleixner	select HAVE_IRQ_EXIT_ON_IRQ_STACK	if X86_64
2296471b825SIngo Molnar	select HAVE_IRQ_TIME_ACCOUNTING
2304ab7674fSJosh Poimboeuf	select HAVE_JUMP_LABEL_HACK		if HAVE_OBJTOOL
2316471b825SIngo Molnar	select HAVE_KERNEL_BZIP2
2326471b825SIngo Molnar	select HAVE_KERNEL_GZIP
2336471b825SIngo Molnar	select HAVE_KERNEL_LZ4
2346471b825SIngo Molnar	select HAVE_KERNEL_LZMA
2356471b825SIngo Molnar	select HAVE_KERNEL_LZO
2366471b825SIngo Molnar	select HAVE_KERNEL_XZ
237fb46d057SNick Terrell	select HAVE_KERNEL_ZSTD
2386471b825SIngo Molnar	select HAVE_KPROBES
2396471b825SIngo Molnar	select HAVE_KPROBES_ON_FTRACE
240540adea3SMasami Hiramatsu	select HAVE_FUNCTION_ERROR_INJECTION
2416471b825SIngo Molnar	select HAVE_KRETPROBES
242f3a112c0SMasami Hiramatsu	select HAVE_RETHOOK
2436471b825SIngo Molnar	select HAVE_KVM
2446471b825SIngo Molnar	select HAVE_LIVEPATCH			if X86_64
2450102752eSFrederic Weisbecker	select HAVE_MIXED_BREAKPOINTS_REGS
246ee9f8fceSJosh Poimboeuf	select HAVE_MOD_ARCH_SPECIFIC
2479f132f7eSJoel Fernandes (Google)	select HAVE_MOVE_PMD
248be37c98dSKalesh Singh	select HAVE_MOVE_PUD
24922102f45SJosh Poimboeuf	select HAVE_NOINSTR_HACK		if HAVE_OBJTOOL
25042a0bb3fSPetr Mladek	select HAVE_NMI
251489e355bSJosh Poimboeuf	select HAVE_NOINSTR_VALIDATION		if HAVE_OBJTOOL
25203f16cd0SJosh Poimboeuf	select HAVE_OBJTOOL			if X86_64
2536471b825SIngo Molnar	select HAVE_OPTPROBES
2546471b825SIngo Molnar	select HAVE_PCSPKR_PLATFORM
2556471b825SIngo Molnar	select HAVE_PERF_EVENTS
256c01d4323SFrederic Weisbecker	select HAVE_PERF_EVENTS_NMI
25792e5aae4SNicholas Piggin	select HAVE_HARDLOCKUP_DETECTOR_PERF	if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
258eb01d42aSChristoph Hellwig	select HAVE_PCI
259c5e63197SJiri Olsa	select HAVE_PERF_REGS
260c5ebcedbSJiri Olsa	select HAVE_PERF_USER_STACK_DUMP
261ff2e6d72SPeter Zijlstra	select MMU_GATHER_RCU_TABLE_FREE	if PARAVIRT
2621e9fdf21SPeter Zijlstra	select MMU_GATHER_MERGE_VMAS
26300998085SThomas Gleixner	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
2646471b825SIngo Molnar	select HAVE_REGS_AND_STACK_ACCESS_API
26503f16cd0SJosh Poimboeuf	select HAVE_RELIABLE_STACKTRACE		if UNWINDER_ORC || STACK_VALIDATION
2663c88ee19SMasami Hiramatsu	select HAVE_FUNCTION_ARG_ACCESS_API
2677ecd19cfSKefeng Wang	select HAVE_SETUP_PER_CPU_AREA
268cd1a41ceSThomas Gleixner	select HAVE_SOFTIRQ_ON_OWN_STACK
269d148eac0SMasahiro Yamada	select HAVE_STACKPROTECTOR		if CC_HAS_SANE_STACKPROTECTOR
27003f16cd0SJosh Poimboeuf	select HAVE_STACK_VALIDATION		if HAVE_OBJTOOL
271e6d6c071SJosh Poimboeuf	select HAVE_STATIC_CALL
27203f16cd0SJosh Poimboeuf	select HAVE_STATIC_CALL_INLINE		if HAVE_OBJTOOL
27399cf983cSMark Rutland	select HAVE_PREEMPT_DYNAMIC_CALL
274d6761b8fSMathieu Desnoyers	select HAVE_RSEQ
27509498135SMiguel Ojeda	select HAVE_RUST			if X86_64
2766471b825SIngo Molnar	select HAVE_SYSCALL_TRACEPOINTS
2775f3da8c0SJosh Poimboeuf	select HAVE_UACCESS_VALIDATION		if HAVE_OBJTOOL
2786471b825SIngo Molnar	select HAVE_UNSTABLE_SCHED_CLOCK
2797c68af6eSAvi Kivity	select HAVE_USER_RETURN_NOTIFIER
2807ac87074SVincenzo Frascino	select HAVE_GENERIC_VDSO
2810c7ffa32SThomas Gleixner	select HOTPLUG_PARALLEL			if SMP && X86_64
28205736e4aSThomas Gleixner	select HOTPLUG_SMT			if SMP
2830c7ffa32SThomas Gleixner	select HOTPLUG_SPLIT_STARTUP		if SMP && X86_32
284c0185808SThomas Gleixner	select IRQ_FORCED_THREADING
285c2508ec5SLinus Torvalds	select LOCK_MM_AND_FIND_VMA
2867ecd19cfSKefeng Wang	select NEED_PER_CPU_EMBED_FIRST_CHUNK
2877ecd19cfSKefeng Wang	select NEED_PER_CPU_PAGE_FIRST_CHUNK
28886596f0aSChristoph Hellwig	select NEED_SG_DMA_LENGTH
2892eac9c2dSChristoph Hellwig	select PCI_DOMAINS			if PCI
290625210cfSSinan Kaya	select PCI_LOCKLESS_CONFIG		if PCI
2916471b825SIngo Molnar	select PERF_EVENTS
2923195ef59SPrarit Bhargava	select RTC_LIB
293d6faca40SArnd Bergmann	select RTC_MC146818_LIB
2946471b825SIngo Molnar	select SPARSE_IRQ
2956471b825SIngo Molnar	select SYSCTL_EXCEPTION_TRACE
29615f4eae7SAndy Lutomirski	select THREAD_INFO_IN_TASK
2974aae683fSMasahiro Yamada	select TRACE_IRQFLAGS_SUPPORT
2984510bffbSMark Rutland	select TRACE_IRQFLAGS_NMI_SUPPORT
2996471b825SIngo Molnar	select USER_STACKTRACE_SUPPORT
3003b02a051SIngo Molnar	select HAVE_ARCH_KCSAN			if X86_64
3010c608dadSAubrey Li	select PROC_PID_ARCH_STATUS		if PROC_FS
30250468e43SJarkko Sakkinen	select HAVE_ARCH_NODE_DEV_GROUP		if X86_SGX
303d49a0626SPeter Zijlstra	select FUNCTION_ALIGNMENT_16B		if X86_64 || X86_ALIGNMENT_16
304d49a0626SPeter Zijlstra	select FUNCTION_ALIGNMENT_4B
3059e2b4be3SNayna Jain	imply IMA_SECURE_AND_OR_TRUSTED_BOOT    if EFI
306ceea991aSJiri Olsa	select HAVE_DYNAMIC_FTRACE_NO_PATCHABLE
3077d8330a5SBalbir Singh
308ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER
3093120e25eSJan Beulich	def_bool y
3103120e25eSJan Beulich	depends on KPROBES || PERF_EVENTS || UPROBES
311ba7e4d13SIngo Molnar
31251b26adaSLinus Torvaldsconfig OUTPUT_FORMAT
31351b26adaSLinus Torvalds	string
31451b26adaSLinus Torvalds	default "elf32-i386" if X86_32
31551b26adaSLinus Torvalds	default "elf64-x86-64" if X86_64
31651b26adaSLinus Torvalds
3178d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT
3183c2362e6SHarvey Harrison	def_bool y
3198d5fffb9SSam Ravnborg
3208d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT
3213c2362e6SHarvey Harrison	def_bool y
3228d5fffb9SSam Ravnborg
3238d5fffb9SSam Ravnborgconfig MMU
3243c2362e6SHarvey Harrison	def_bool y
3258d5fffb9SSam Ravnborg
3269e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN
3279e08f57dSDaniel Cashman	default 28 if 64BIT
3289e08f57dSDaniel Cashman	default 8
3299e08f57dSDaniel Cashman
3309e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX
3319e08f57dSDaniel Cashman	default 32 if 64BIT
3329e08f57dSDaniel Cashman	default 16
3339e08f57dSDaniel Cashman
3349e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN
3359e08f57dSDaniel Cashman	default 8
3369e08f57dSDaniel Cashman
3379e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX
3389e08f57dSDaniel Cashman	default 16
3399e08f57dSDaniel Cashman
3408d5fffb9SSam Ravnborgconfig SBUS
3418d5fffb9SSam Ravnborg	bool
3428d5fffb9SSam Ravnborg
3438d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA
3443120e25eSJan Beulich	def_bool y
3453120e25eSJan Beulich	depends on ISA_DMA_API
3468d5fffb9SSam Ravnborg
347d911c67eSAlexander Potapenkoconfig GENERIC_CSUM
348d911c67eSAlexander Potapenko	bool
349d911c67eSAlexander Potapenko	default y if KMSAN || KASAN
350d911c67eSAlexander Potapenko
3518d5fffb9SSam Ravnborgconfig GENERIC_BUG
3523c2362e6SHarvey Harrison	def_bool y
3538d5fffb9SSam Ravnborg	depends on BUG
354b93a531eSJan Beulich	select GENERIC_BUG_RELATIVE_POINTERS if X86_64
355b93a531eSJan Beulich
356b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS
357b93a531eSJan Beulich	bool
3588d5fffb9SSam Ravnborg
3598d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC
3603120e25eSJan Beulich	def_bool y
3613120e25eSJan Beulich	depends on ISA_DMA_API
3628d5fffb9SSam Ravnborg
3631032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY
3641032c0baSSam Ravnborg	def_bool y
3651032c0baSSam Ravnborg
3669a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX
3679a0b8415Svenkatesh.pallipadi@intel.com	def_bool y
3688d5fffb9SSam Ravnborg
369801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE
370801e4062SJohannes Berg	def_bool y
371801e4062SJohannes Berg
372f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE
373f4cb5700SJohannes Berg	def_bool y
374f4cb5700SJohannes Berg
3758d5fffb9SSam Ravnborgconfig AUDIT_ARCH
376e0fd24a3SJan Beulich	def_bool y if X86_64
3778d5fffb9SSam Ravnborg
378d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET
379d6f2d75aSAndrey Ryabinin	hex
380d6f2d75aSAndrey Ryabinin	depends on KASAN
381d6f2d75aSAndrey Ryabinin	default 0xdffffc0000000000
382d6f2d75aSAndrey Ryabinin
38369575d38SShane Wangconfig HAVE_INTEL_TXT
38469575d38SShane Wang	def_bool y
3856ea30386SKees Cook	depends on INTEL_IOMMU && ACPI
38669575d38SShane Wang
3876b0c3d44SSam Ravnborgconfig X86_32_SMP
3886b0c3d44SSam Ravnborg	def_bool y
3896b0c3d44SSam Ravnborg	depends on X86_32 && SMP
3906b0c3d44SSam Ravnborg
3916b0c3d44SSam Ravnborgconfig X86_64_SMP
3926b0c3d44SSam Ravnborg	def_bool y
3936b0c3d44SSam Ravnborg	depends on X86_64 && SMP
3946b0c3d44SSam Ravnborg
3952b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES
3962b144498SSrikar Dronamraju	def_bool y
3972b144498SSrikar Dronamraju
398d20642f0SRob Herringconfig FIX_EARLYCON_MEM
399d20642f0SRob Herring	def_bool y
400d20642f0SRob Herring
40194d49eb3SKirill A. Shutemovconfig DYNAMIC_PHYSICAL_MASK
40294d49eb3SKirill A. Shutemov	bool
40394d49eb3SKirill A. Shutemov
40498233368SKirill A. Shutemovconfig PGTABLE_LEVELS
40598233368SKirill A. Shutemov	int
40677ef56e4SKirill A. Shutemov	default 5 if X86_5LEVEL
40798233368SKirill A. Shutemov	default 4 if X86_64
40898233368SKirill A. Shutemov	default 3 if X86_PAE
40998233368SKirill A. Shutemov	default 2
41098233368SKirill A. Shutemov
4112a61f474SMasahiro Yamadaconfig CC_HAS_SANE_STACKPROTECTOR
4122a61f474SMasahiro Yamada	bool
4131b866781SNathan Chancellor	default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC) $(CLANG_FLAGS)) if 64BIT
4141b866781SNathan Chancellor	default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC) $(CLANG_FLAGS))
4152a61f474SMasahiro Yamada	help
4162a61f474SMasahiro Yamada	  We have to make sure stack protector is unconditionally disabled if
4173fb0fdb3SAndy Lutomirski	  the compiler produces broken code or if it does not let us control
4183fb0fdb3SAndy Lutomirski	  the segment on 32-bit kernels.
4192a61f474SMasahiro Yamada
420506f1d07SSam Ravnborgmenu "Processor type and features"
421506f1d07SSam Ravnborg
422506f1d07SSam Ravnborgconfig SMP
423506f1d07SSam Ravnborg	bool "Symmetric multi-processing support"
424a7f7f624SMasahiro Yamada	help
425506f1d07SSam Ravnborg	  This enables support for systems with more than one CPU. If you have
4264a474157SRobert Graffham	  a system with only one CPU, say N. If you have a system with more
4274a474157SRobert Graffham	  than one CPU, say Y.
428506f1d07SSam Ravnborg
4294a474157SRobert Graffham	  If you say N here, the kernel will run on uni- and multiprocessor
430506f1d07SSam Ravnborg	  machines, but will use only one CPU of a multiprocessor machine. If
431506f1d07SSam Ravnborg	  you say Y here, the kernel will run on many, but not all,
4324a474157SRobert Graffham	  uniprocessor machines. On a uniprocessor machine, the kernel
433506f1d07SSam Ravnborg	  will run faster if you say N here.
434506f1d07SSam Ravnborg
435506f1d07SSam Ravnborg	  Note that if you say Y here and choose architecture "586" or
436506f1d07SSam Ravnborg	  "Pentium" under "Processor family", the kernel will not work on 486
437506f1d07SSam Ravnborg	  architectures. Similarly, multiprocessor kernels for the "PPro"
438506f1d07SSam Ravnborg	  architecture may not work on all Pentium based boards.
439506f1d07SSam Ravnborg
440506f1d07SSam Ravnborg	  People using multiprocessor machines who say Y here should also say
441506f1d07SSam Ravnborg	  Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
442506f1d07SSam Ravnborg	  Management" code will be disabled if you say Y here.
443506f1d07SSam Ravnborg
444ff61f079SJonathan Corbet	  See also <file:Documentation/arch/x86/i386/IO-APIC.rst>,
4454f4cfa6cSMauro Carvalho Chehab	  <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
446506f1d07SSam Ravnborg	  <http://www.tldp.org/docs.html#howto>.
447506f1d07SSam Ravnborg
448506f1d07SSam Ravnborg	  If you don't know what to do here, say N.
449506f1d07SSam Ravnborg
45006cd9a7dSYinghai Luconfig X86_X2APIC
45106cd9a7dSYinghai Lu	bool "Support x2apic"
45219e3d60dSJan Kiszka	depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
453a7f7f624SMasahiro Yamada	help
45406cd9a7dSYinghai Lu	  This enables x2apic support on CPUs that have this feature.
45506cd9a7dSYinghai Lu
45606cd9a7dSYinghai Lu	  This allows 32-bit apic IDs (so it can support very large systems),
45706cd9a7dSYinghai Lu	  and accesses the local apic via MSRs not via mmio.
45806cd9a7dSYinghai Lu
459b8d1d163SDaniel Sneddon	  Some Intel systems circa 2022 and later are locked into x2APIC mode
460b8d1d163SDaniel Sneddon	  and can not fall back to the legacy APIC modes if SGX or TDX are
461e3998434SMateusz Jończyk	  enabled in the BIOS. They will boot with very reduced functionality
462e3998434SMateusz Jończyk	  without enabling this option.
463b8d1d163SDaniel Sneddon
46406cd9a7dSYinghai Lu	  If you don't know what to do here, say N.
46506cd9a7dSYinghai Lu
4666695c85bSYinghai Luconfig X86_MPPARSE
4674590d98fSAndy Shevchenko	bool "Enable MPS table" if ACPI
4687a527688SJan Beulich	default y
4695ab74722SIngo Molnar	depends on X86_LOCAL_APIC
470a7f7f624SMasahiro Yamada	help
4716695c85bSYinghai Lu	  For old smp systems that do not have proper acpi support. Newer systems
4726695c85bSYinghai Lu	  (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
4736695c85bSYinghai Lu
474ddd70cf9SJun Nakajimaconfig GOLDFISH
475ddd70cf9SJun Nakajima	def_bool y
476ddd70cf9SJun Nakajima	depends on X86_GOLDFISH
477ddd70cf9SJun Nakajima
478e6d42931SJohannes Weinerconfig X86_CPU_RESCTRL
479e6d42931SJohannes Weiner	bool "x86 CPU resource control support"
4806fe07ce3SBabu Moger	depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
48159fe5a77SThomas Gleixner	select KERNFS
482e79f15a4SChen Yu	select PROC_CPU_RESCTRL		if PROC_FS
48378e99b4aSFenghua Yu	help
484e6d42931SJohannes Weiner	  Enable x86 CPU resource control support.
4856fe07ce3SBabu Moger
4866fe07ce3SBabu Moger	  Provide support for the allocation and monitoring of system resources
4876fe07ce3SBabu Moger	  usage by the CPU.
4886fe07ce3SBabu Moger
4896fe07ce3SBabu Moger	  Intel calls this Intel Resource Director Technology
4906fe07ce3SBabu Moger	  (Intel(R) RDT). More information about RDT can be found in the
4916fe07ce3SBabu Moger	  Intel x86 Architecture Software Developer Manual.
4926fe07ce3SBabu Moger
4936fe07ce3SBabu Moger	  AMD calls this AMD Platform Quality of Service (AMD QoS).
4946fe07ce3SBabu Moger	  More information about AMD QoS can be found in the AMD64 Technology
4956fe07ce3SBabu Moger	  Platform Quality of Service Extensions manual.
49678e99b4aSFenghua Yu
49778e99b4aSFenghua Yu	  Say N if unsure.
49878e99b4aSFenghua Yu
4998425091fSRavikiran G Thirumalaiif X86_32
500a0d0bb4dSRandy Dunlapconfig X86_BIGSMP
501a0d0bb4dSRandy Dunlap	bool "Support for big SMP systems with more than 8 CPUs"
502a0d0bb4dSRandy Dunlap	depends on SMP
503a7f7f624SMasahiro Yamada	help
504e133f6eaSRandy Dunlap	  This option is needed for the systems that have more than 8 CPUs.
505a0d0bb4dSRandy Dunlap
506c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM
507c5c606d9SRavikiran G Thirumalai	bool "Support for extended (non-PC) x86 platforms"
508c5c606d9SRavikiran G Thirumalai	default y
509a7f7f624SMasahiro Yamada	help
51006ac8346SIngo Molnar	  If you disable this option then the kernel will only support
51106ac8346SIngo Molnar	  standard PC platforms. (which covers the vast majority of
51206ac8346SIngo Molnar	  systems out there.)
51306ac8346SIngo Molnar
5148425091fSRavikiran G Thirumalai	  If you enable this option then you'll be able to select support
5158425091fSRavikiran G Thirumalai	  for the following (non-PC) 32 bit x86 platforms:
516cb7b8023SBen Hutchings		Goldfish (Android emulator)
5178425091fSRavikiran G Thirumalai		AMD Elan
5188425091fSRavikiran G Thirumalai		RDC R-321x SoC
5198425091fSRavikiran G Thirumalai		SGI 320/540 (Visual Workstation)
52083125a3aSAlessandro Rubini		STA2X11-based (e.g. Northville)
5213f4110a4SThomas Gleixner		Moorestown MID devices
52206ac8346SIngo Molnar
52306ac8346SIngo Molnar	  If you have one of these systems, or if you want to build a
52406ac8346SIngo Molnar	  generic distribution kernel, say Y here - otherwise say N.
525758cd94aSJuerg Haefligerendif # X86_32
52606ac8346SIngo Molnar
5278425091fSRavikiran G Thirumalaiif X86_64
5288425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM
5298425091fSRavikiran G Thirumalai	bool "Support for extended (non-PC) x86 platforms"
5308425091fSRavikiran G Thirumalai	default y
531a7f7f624SMasahiro Yamada	help
5328425091fSRavikiran G Thirumalai	  If you disable this option then the kernel will only support
5338425091fSRavikiran G Thirumalai	  standard PC platforms. (which covers the vast majority of
5348425091fSRavikiran G Thirumalai	  systems out there.)
5358425091fSRavikiran G Thirumalai
5368425091fSRavikiran G Thirumalai	  If you enable this option then you'll be able to select support
5378425091fSRavikiran G Thirumalai	  for the following (non-PC) 64 bit x86 platforms:
53844b111b5SSteffen Persvold		Numascale NumaChip
5398425091fSRavikiran G Thirumalai		ScaleMP vSMP
5408425091fSRavikiran G Thirumalai		SGI Ultraviolet
5418425091fSRavikiran G Thirumalai
5428425091fSRavikiran G Thirumalai	  If you have one of these systems, or if you want to build a
5438425091fSRavikiran G Thirumalai	  generic distribution kernel, say Y here - otherwise say N.
544758cd94aSJuerg Haefligerendif # X86_64
545c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms
546c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions
54744b111b5SSteffen Persvoldconfig X86_NUMACHIP
54844b111b5SSteffen Persvold	bool "Numascale NumaChip"
54944b111b5SSteffen Persvold	depends on X86_64
55044b111b5SSteffen Persvold	depends on X86_EXTENDED_PLATFORM
55144b111b5SSteffen Persvold	depends on NUMA
55244b111b5SSteffen Persvold	depends on SMP
55344b111b5SSteffen Persvold	depends on X86_X2APIC
554f9726bfdSDaniel J Blueman	depends on PCI_MMCONFIG
555a7f7f624SMasahiro Yamada	help
55644b111b5SSteffen Persvold	  Adds support for Numascale NumaChip large-SMP systems. Needed to
55744b111b5SSteffen Persvold	  enable more than ~168 cores.
55844b111b5SSteffen Persvold	  If you don't have one of these, you should say N here.
55903b48632SNick Piggin
5606a48565eSIngo Molnarconfig X86_VSMP
561c5c606d9SRavikiran G Thirumalai	bool "ScaleMP vSMP"
5626276a074SBorislav Petkov	select HYPERVISOR_GUEST
5636a48565eSIngo Molnar	select PARAVIRT
5646a48565eSIngo Molnar	depends on X86_64 && PCI
565c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
566ead91d4bSShai Fultheim	depends on SMP
567a7f7f624SMasahiro Yamada	help
5686a48565eSIngo Molnar	  Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
5696a48565eSIngo Molnar	  supposed to run on these EM64T-based machines.  Only choose this option
5706a48565eSIngo Molnar	  if you have one of these machines.
5716a48565eSIngo Molnar
572c5c606d9SRavikiran G Thirumalaiconfig X86_UV
573c5c606d9SRavikiran G Thirumalai	bool "SGI Ultraviolet"
574c5c606d9SRavikiran G Thirumalai	depends on X86_64
575c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
57654c28d29SJack Steiner	depends on NUMA
5771ecb4ae5SAndrew Morton	depends on EFI
578c2209ea5SIngo Molnar	depends on KEXEC_CORE
5799d6c26e7SSuresh Siddha	depends on X86_X2APIC
5801222e564SIngo Molnar	depends on PCI
581a7f7f624SMasahiro Yamada	help
582c5c606d9SRavikiran G Thirumalai	  This option is needed in order to support SGI Ultraviolet systems.
583c5c606d9SRavikiran G Thirumalai	  If you don't have one of these, you should say N here.
584c5c606d9SRavikiran G Thirumalai
585c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms
586c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions
587506f1d07SSam Ravnborg
588ddd70cf9SJun Nakajimaconfig X86_GOLDFISH
589ddd70cf9SJun Nakajima	bool "Goldfish (Virtual Platform)"
590cb7b8023SBen Hutchings	depends on X86_EXTENDED_PLATFORM
591a7f7f624SMasahiro Yamada	help
592ddd70cf9SJun Nakajima	  Enable support for the Goldfish virtual platform used primarily
593ddd70cf9SJun Nakajima	  for Android development. Unless you are building for the Android
594ddd70cf9SJun Nakajima	  Goldfish emulator say N here.
595ddd70cf9SJun Nakajima
596c751e17bSThomas Gleixnerconfig X86_INTEL_CE
597c751e17bSThomas Gleixner	bool "CE4100 TV platform"
598c751e17bSThomas Gleixner	depends on PCI
599c751e17bSThomas Gleixner	depends on PCI_GODIRECT
6006084a6e2SJiang Liu	depends on X86_IO_APIC
601c751e17bSThomas Gleixner	depends on X86_32
602c751e17bSThomas Gleixner	depends on X86_EXTENDED_PLATFORM
60337bc9f50SDirk Brandewie	select X86_REBOOTFIXUPS
604da6b737bSSebastian Andrzej Siewior	select OF
605da6b737bSSebastian Andrzej Siewior	select OF_EARLY_FLATTREE
606a7f7f624SMasahiro Yamada	help
607c751e17bSThomas Gleixner	  Select for the Intel CE media processor (CE4100) SOC.
608c751e17bSThomas Gleixner	  This option compiles in support for the CE4100 SOC for settop
609c751e17bSThomas Gleixner	  boxes and media devices.
610c751e17bSThomas Gleixner
6114cb9b00fSDavid Cohenconfig X86_INTEL_MID
61243605ef1SAlan Cox	bool "Intel MID platform support"
61343605ef1SAlan Cox	depends on X86_EXTENDED_PLATFORM
614edc6bc78SDavid Cohen	depends on X86_PLATFORM_DEVICES
6151ea7c673SAlan Cox	depends on PCI
6163fda5bb4SAndy Shevchenko	depends on X86_64 || (PCI_GOANY && X86_32)
6171ea7c673SAlan Cox	depends on X86_IO_APIC
6184cb9b00fSDavid Cohen	select I2C
6197c9c3a1eSAlan Cox	select DW_APB_TIMER
62054b34aa0SMika Westerberg	select INTEL_SCU_PCI
621a7f7f624SMasahiro Yamada	help
6224cb9b00fSDavid Cohen	  Select to build a kernel capable of supporting Intel MID (Mobile
6234cb9b00fSDavid Cohen	  Internet Device) platform systems which do not have the PCI legacy
6244cb9b00fSDavid Cohen	  interfaces. If you are building for a PC class system say N here.
6251ea7c673SAlan Cox
6264cb9b00fSDavid Cohen	  Intel MID platforms are based on an Intel processor and chipset which
6274cb9b00fSDavid Cohen	  consume less power than most of the x86 derivatives.
62843605ef1SAlan Cox
6298bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK
6308bbc2a13SBryan O'Donoghue	bool "Intel Quark platform support"
6318bbc2a13SBryan O'Donoghue	depends on X86_32
6328bbc2a13SBryan O'Donoghue	depends on X86_EXTENDED_PLATFORM
6338bbc2a13SBryan O'Donoghue	depends on X86_PLATFORM_DEVICES
6348bbc2a13SBryan O'Donoghue	depends on X86_TSC
6358bbc2a13SBryan O'Donoghue	depends on PCI
6368bbc2a13SBryan O'Donoghue	depends on PCI_GOANY
6378bbc2a13SBryan O'Donoghue	depends on X86_IO_APIC
6388bbc2a13SBryan O'Donoghue	select IOSF_MBI
6398bbc2a13SBryan O'Donoghue	select INTEL_IMR
6409ab6eb51SAndy Shevchenko	select COMMON_CLK
641a7f7f624SMasahiro Yamada	help
6428bbc2a13SBryan O'Donoghue	  Select to include support for Quark X1000 SoC.
6438bbc2a13SBryan O'Donoghue	  Say Y here if you have a Quark based system such as the Arduino
6448bbc2a13SBryan O'Donoghue	  compatible Intel Galileo.
6458bbc2a13SBryan O'Donoghue
6463d48aab1SMika Westerbergconfig X86_INTEL_LPSS
6473d48aab1SMika Westerberg	bool "Intel Low Power Subsystem Support"
6485962dd22SSinan Kaya	depends on X86 && ACPI && PCI
6493d48aab1SMika Westerberg	select COMMON_CLK
6500f531431SMathias Nyman	select PINCTRL
651eebb3e8dSAndy Shevchenko	select IOSF_MBI
652a7f7f624SMasahiro Yamada	help
6533d48aab1SMika Westerberg	  Select to build support for Intel Low Power Subsystem such as
6543d48aab1SMika Westerberg	  found on Intel Lynxpoint PCH. Selecting this option enables
6550f531431SMathias Nyman	  things like clock tree (common clock framework) and pincontrol
6560f531431SMathias Nyman	  which are needed by the LPSS peripheral drivers.
6573d48aab1SMika Westerberg
65892082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE
65992082a88SKen Xue	bool "AMD ACPI2Platform devices support"
66092082a88SKen Xue	depends on ACPI
66192082a88SKen Xue	select COMMON_CLK
66292082a88SKen Xue	select PINCTRL
663a7f7f624SMasahiro Yamada	help
66492082a88SKen Xue	  Select to interpret AMD specific ACPI device to platform device
66592082a88SKen Xue	  such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
66692082a88SKen Xue	  I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
66792082a88SKen Xue	  implemented under PINCTRL subsystem.
66892082a88SKen Xue
669ced3ce76SDavid E. Boxconfig IOSF_MBI
670ced3ce76SDavid E. Box	tristate "Intel SoC IOSF Sideband support for SoC platforms"
671ced3ce76SDavid E. Box	depends on PCI
672a7f7f624SMasahiro Yamada	help
673ced3ce76SDavid E. Box	  This option enables sideband register access support for Intel SoC
674ced3ce76SDavid E. Box	  platforms. On these platforms the IOSF sideband is used in lieu of
675ced3ce76SDavid E. Box	  MSR's for some register accesses, mostly but not limited to thermal
676ced3ce76SDavid E. Box	  and power. Drivers may query the availability of this device to
677ced3ce76SDavid E. Box	  determine if they need the sideband in order to work on these
678ced3ce76SDavid E. Box	  platforms. The sideband is available on the following SoC products.
679ced3ce76SDavid E. Box	  This list is not meant to be exclusive.
680ced3ce76SDavid E. Box	   - BayTrail
681ced3ce76SDavid E. Box	   - Braswell
682ced3ce76SDavid E. Box	   - Quark
683ced3ce76SDavid E. Box
684ced3ce76SDavid E. Box	  You should say Y if you are running a kernel on one of these SoC's.
685ced3ce76SDavid E. Box
686ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG
687ed2226bdSDavid E. Box	bool "Enable IOSF sideband access through debugfs"
688ed2226bdSDavid E. Box	depends on IOSF_MBI && DEBUG_FS
689a7f7f624SMasahiro Yamada	help
690ed2226bdSDavid E. Box	  Select this option to expose the IOSF sideband access registers (MCR,
691ed2226bdSDavid E. Box	  MDR, MCRX) through debugfs to write and read register information from
692ed2226bdSDavid E. Box	  different units on the SoC. This is most useful for obtaining device
693ed2226bdSDavid E. Box	  state information for debug and analysis. As this is a general access
694ed2226bdSDavid E. Box	  mechanism, users of this option would have specific knowledge of the
695ed2226bdSDavid E. Box	  device they want to access.
696ed2226bdSDavid E. Box
697ed2226bdSDavid E. Box	  If you don't require the option or are in doubt, say N.
698ed2226bdSDavid E. Box
699c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X
700c5c606d9SRavikiran G Thirumalai	bool "RDC R-321x SoC"
701506f1d07SSam Ravnborg	depends on X86_32
702c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
703c5c606d9SRavikiran G Thirumalai	select M486
704c5c606d9SRavikiran G Thirumalai	select X86_REBOOTFIXUPS
705a7f7f624SMasahiro Yamada	help
706c5c606d9SRavikiran G Thirumalai	  This option is needed for RDC R-321x system-on-chip, also known
707c5c606d9SRavikiran G Thirumalai	  as R-8610-(G).
708c5c606d9SRavikiran G Thirumalai	  If you don't have one of these chips, you should say N here.
709c5c606d9SRavikiran G Thirumalai
710e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD
7119c398017SIngo Molnar	bool "Support non-standard 32-bit SMP architectures"
7129c398017SIngo Molnar	depends on X86_32 && SMP
713c5c606d9SRavikiran G Thirumalai	depends on X86_EXTENDED_PLATFORM
714a7f7f624SMasahiro Yamada	help
715b5660ba7SH. Peter Anvin	  This option compiles in the bigsmp and STA2X11 default
716b5660ba7SH. Peter Anvin	  subarchitectures.  It is intended for a generic binary
717b5660ba7SH. Peter Anvin	  kernel. If you select them all, kernel will probe it one by
718b5660ba7SH. Peter Anvin	  one and will fallback to default.
719d49c4288SYinghai Lu
720c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms
721d49c4288SYinghai Lu
722d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE
7236fc108a0SJan Beulich	def_bool y
724d949f36fSLinus Torvalds	# MCE code calls memory_failure():
725d949f36fSLinus Torvalds	depends on X86_MCE
726d949f36fSLinus Torvalds	# On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
727d949f36fSLinus Torvalds	# On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
728d949f36fSLinus Torvalds	depends on X86_64 || !SPARSEMEM
729d949f36fSLinus Torvalds	select ARCH_SUPPORTS_MEMORY_FAILURE
730d949f36fSLinus Torvalds
73183125a3aSAlessandro Rubiniconfig STA2X11
73283125a3aSAlessandro Rubini	bool "STA2X11 Companion Chip Support"
73383125a3aSAlessandro Rubini	depends on X86_32_NON_STANDARD && PCI
73483125a3aSAlessandro Rubini	select SWIOTLB
73583125a3aSAlessandro Rubini	select MFD_STA2X11
7360145071bSLinus Walleij	select GPIOLIB
737a7f7f624SMasahiro Yamada	help
73883125a3aSAlessandro Rubini	  This adds support for boards based on the STA2X11 IO-Hub,
73983125a3aSAlessandro Rubini	  a.k.a. "ConneXt". The chip is used in place of the standard
74083125a3aSAlessandro Rubini	  PC chipset, so all "standard" peripherals are missing. If this
74183125a3aSAlessandro Rubini	  option is selected the kernel will still be able to boot on
74283125a3aSAlessandro Rubini	  standard PC machines.
74383125a3aSAlessandro Rubini
74482148d1dSShérabconfig X86_32_IRIS
74582148d1dSShérab	tristate "Eurobraille/Iris poweroff module"
74682148d1dSShérab	depends on X86_32
747a7f7f624SMasahiro Yamada	help
74882148d1dSShérab	  The Iris machines from EuroBraille do not have APM or ACPI support
74982148d1dSShérab	  to shut themselves down properly.  A special I/O sequence is
75082148d1dSShérab	  needed to do so, which is what this module does at
75182148d1dSShérab	  kernel shutdown.
75282148d1dSShérab
75382148d1dSShérab	  This is only for Iris machines from EuroBraille.
75482148d1dSShérab
75582148d1dSShérab	  If unused, say N.
75682148d1dSShérab
757ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER
7583c2362e6SHarvey Harrison	def_bool y
7593c2362e6SHarvey Harrison	prompt "Single-depth WCHAN output"
760a87d0914SKen Chen	depends on X86
761a7f7f624SMasahiro Yamada	help
762506f1d07SSam Ravnborg	  Calculate simpler /proc/<PID>/wchan values. If this option
763506f1d07SSam Ravnborg	  is disabled then wchan values will recurse back to the
764506f1d07SSam Ravnborg	  caller function. This provides more accurate wchan values,
765506f1d07SSam Ravnborg	  at the expense of slightly more scheduling overhead.
766506f1d07SSam Ravnborg
767506f1d07SSam Ravnborg	  If in doubt, say "Y".
768506f1d07SSam Ravnborg
7696276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST
7706276a074SBorislav Petkov	bool "Linux guest support"
771a7f7f624SMasahiro Yamada	help
7726276a074SBorislav Petkov	  Say Y here to enable options for running Linux under various hyper-
7736276a074SBorislav Petkov	  visors. This option enables basic hypervisor detection and platform
7746276a074SBorislav Petkov	  setup.
775506f1d07SSam Ravnborg
7766276a074SBorislav Petkov	  If you say N, all options in this submenu will be skipped and
7776276a074SBorislav Petkov	  disabled, and Linux guest support won't be built in.
778506f1d07SSam Ravnborg
7796276a074SBorislav Petkovif HYPERVISOR_GUEST
780506f1d07SSam Ravnborg
781e61bd94aSEduardo Pereira Habkostconfig PARAVIRT
782e61bd94aSEduardo Pereira Habkost	bool "Enable paravirtualization code"
783a0e2bf7cSJuergen Gross	depends on HAVE_STATIC_CALL
784a7f7f624SMasahiro Yamada	help
785e61bd94aSEduardo Pereira Habkost	  This changes the kernel so it can modify itself when it is run
786e61bd94aSEduardo Pereira Habkost	  under a hypervisor, potentially improving performance significantly
787e61bd94aSEduardo Pereira Habkost	  over full virtualization.  However, when run without a hypervisor
788e61bd94aSEduardo Pereira Habkost	  the kernel is theoretically slower and slightly larger.
789e61bd94aSEduardo Pereira Habkost
790c00a280aSJuergen Grossconfig PARAVIRT_XXL
791c00a280aSJuergen Gross	bool
792c00a280aSJuergen Gross
7936276a074SBorislav Petkovconfig PARAVIRT_DEBUG
7946276a074SBorislav Petkov	bool "paravirt-ops debugging"
7956276a074SBorislav Petkov	depends on PARAVIRT && DEBUG_KERNEL
796a7f7f624SMasahiro Yamada	help
7976276a074SBorislav Petkov	  Enable to debug paravirt_ops internals.  Specifically, BUG if
7986276a074SBorislav Petkov	  a paravirt_op is missing when it is called.
7996276a074SBorislav Petkov
800b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS
801b4ecc126SJeremy Fitzhardinge	bool "Paravirtualization layer for spinlocks"
8026ea30386SKees Cook	depends on PARAVIRT && SMP
803a7f7f624SMasahiro Yamada	help
804b4ecc126SJeremy Fitzhardinge	  Paravirtualized spinlocks allow a pvops backend to replace the
805b4ecc126SJeremy Fitzhardinge	  spinlock implementation with something virtualization-friendly
806b4ecc126SJeremy Fitzhardinge	  (for example, block the virtual CPU rather than spinning).
807b4ecc126SJeremy Fitzhardinge
8084c4e4f61SRaghavendra K T	  It has a minimal impact on native kernels and gives a nice performance
8094c4e4f61SRaghavendra K T	  benefit on paravirtualized KVM / Xen kernels.
810b4ecc126SJeremy Fitzhardinge
8114c4e4f61SRaghavendra K T	  If you are unsure how to answer this question, answer Y.
812b4ecc126SJeremy Fitzhardinge
813ecca2502SZhao Yakuiconfig X86_HV_CALLBACK_VECTOR
814ecca2502SZhao Yakui	def_bool n
815ecca2502SZhao Yakui
8166276a074SBorislav Petkovsource "arch/x86/xen/Kconfig"
8176276a074SBorislav Petkov
8186276a074SBorislav Petkovconfig KVM_GUEST
8196276a074SBorislav Petkov	bool "KVM Guest support (including kvmclock)"
8206276a074SBorislav Petkov	depends on PARAVIRT
8216276a074SBorislav Petkov	select PARAVIRT_CLOCK
822a1c4423bSMarcelo Tosatti	select ARCH_CPUIDLE_HALTPOLL
823b1d40575SVitaly Kuznetsov	select X86_HV_CALLBACK_VECTOR
8246276a074SBorislav Petkov	default y
825a7f7f624SMasahiro Yamada	help
8266276a074SBorislav Petkov	  This option enables various optimizations for running under the KVM
8276276a074SBorislav Petkov	  hypervisor. It includes a paravirtualized clock, so that instead
8286276a074SBorislav Petkov	  of relying on a PIT (or probably other) emulation by the
8296276a074SBorislav Petkov	  underlying device model, the host provides the guest with
8306276a074SBorislav Petkov	  timing infrastructure such as time of day, and system time
8316276a074SBorislav Petkov
832a1c4423bSMarcelo Tosatticonfig ARCH_CPUIDLE_HALTPOLL
833a1c4423bSMarcelo Tosatti	def_bool n
834a1c4423bSMarcelo Tosatti	prompt "Disable host haltpoll when loading haltpoll driver"
835a1c4423bSMarcelo Tosatti	help
836a1c4423bSMarcelo Tosatti	  If virtualized under KVM, disable host haltpoll.
837a1c4423bSMarcelo Tosatti
8387733607fSMaran Wilsonconfig PVH
8397733607fSMaran Wilson	bool "Support for running PVH guests"
840a7f7f624SMasahiro Yamada	help
8417733607fSMaran Wilson	  This option enables the PVH entry point for guest virtual machines
8427733607fSMaran Wilson	  as specified in the x86/HVM direct boot ABI.
8437733607fSMaran Wilson
8446276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING
8456276a074SBorislav Petkov	bool "Paravirtual steal time accounting"
8466276a074SBorislav Petkov	depends on PARAVIRT
847a7f7f624SMasahiro Yamada	help
8486276a074SBorislav Petkov	  Select this option to enable fine granularity task steal time
8496276a074SBorislav Petkov	  accounting. Time spent executing other tasks in parallel with
8506276a074SBorislav Petkov	  the current vCPU is discounted from the vCPU power. To account for
8516276a074SBorislav Petkov	  that, there can be a small performance impact.
8526276a074SBorislav Petkov
8536276a074SBorislav Petkov	  If in doubt, say N here.
8546276a074SBorislav Petkov
8557af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK
8567af192c9SGerd Hoffmann	bool
8577af192c9SGerd Hoffmann
8584a362601SJan Kiszkaconfig JAILHOUSE_GUEST
8594a362601SJan Kiszka	bool "Jailhouse non-root cell support"
860abde587bSArnd Bergmann	depends on X86_64 && PCI
86187e65d05SJan Kiszka	select X86_PM_TIMER
862a7f7f624SMasahiro Yamada	help
8634a362601SJan Kiszka	  This option allows to run Linux as guest in a Jailhouse non-root
8644a362601SJan Kiszka	  cell. You can leave this option disabled if you only want to start
8654a362601SJan Kiszka	  Jailhouse and run Linux afterwards in the root cell.
8664a362601SJan Kiszka
867ec7972c9SZhao Yakuiconfig ACRN_GUEST
868ec7972c9SZhao Yakui	bool "ACRN Guest support"
869ec7972c9SZhao Yakui	depends on X86_64
870498ad393SZhao Yakui	select X86_HV_CALLBACK_VECTOR
871ec7972c9SZhao Yakui	help
872ec7972c9SZhao Yakui	  This option allows to run Linux as guest in the ACRN hypervisor. ACRN is
873ec7972c9SZhao Yakui	  a flexible, lightweight reference open-source hypervisor, built with
874ec7972c9SZhao Yakui	  real-time and safety-criticality in mind. It is built for embedded
875ec7972c9SZhao Yakui	  IOT with small footprint and real-time features. More details can be
876ec7972c9SZhao Yakui	  found in https://projectacrn.org/.
877ec7972c9SZhao Yakui
87859bd54a8SKuppuswamy Sathyanarayananconfig INTEL_TDX_GUEST
87959bd54a8SKuppuswamy Sathyanarayanan	bool "Intel TDX (Trust Domain Extensions) - Guest Support"
88059bd54a8SKuppuswamy Sathyanarayanan	depends on X86_64 && CPU_SUP_INTEL
88159bd54a8SKuppuswamy Sathyanarayanan	depends on X86_X2APIC
88275d090fdSKirill A. Shutemov	depends on EFI_STUB
88341394e33SKirill A. Shutemov	select ARCH_HAS_CC_PLATFORM
884968b4931SKirill A. Shutemov	select X86_MEM_ENCRYPT
88577a512e3SSean Christopherson	select X86_MCE
88675d090fdSKirill A. Shutemov	select UNACCEPTED_MEMORY
88759bd54a8SKuppuswamy Sathyanarayanan	help
88859bd54a8SKuppuswamy Sathyanarayanan	  Support running as a guest under Intel TDX.  Without this support,
88959bd54a8SKuppuswamy Sathyanarayanan	  the guest kernel can not boot or run under TDX.
89059bd54a8SKuppuswamy Sathyanarayanan	  TDX includes memory encryption and integrity capabilities
89159bd54a8SKuppuswamy Sathyanarayanan	  which protect the confidentiality and integrity of guest
89259bd54a8SKuppuswamy Sathyanarayanan	  memory contents and CPU state. TDX guests are protected from
89359bd54a8SKuppuswamy Sathyanarayanan	  some attacks from the VMM.
89459bd54a8SKuppuswamy Sathyanarayanan
8956276a074SBorislav Petkovendif # HYPERVISOR_GUEST
89697349135SJeremy Fitzhardinge
897506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu"
898506f1d07SSam Ravnborg
899506f1d07SSam Ravnborgconfig HPET_TIMER
9003c2362e6SHarvey Harrison	def_bool X86_64
901506f1d07SSam Ravnborg	prompt "HPET Timer Support" if X86_32
902a7f7f624SMasahiro Yamada	help
903506f1d07SSam Ravnborg	  Use the IA-PC HPET (High Precision Event Timer) to manage
904506f1d07SSam Ravnborg	  time in preference to the PIT and RTC, if a HPET is
905506f1d07SSam Ravnborg	  present.
906506f1d07SSam Ravnborg	  HPET is the next generation timer replacing legacy 8254s.
907506f1d07SSam Ravnborg	  The HPET provides a stable time base on SMP
908506f1d07SSam Ravnborg	  systems, unlike the TSC, but it is more expensive to access,
9094e7f9df2SMichael S. Tsirkin	  as it is off-chip.  The interface used is documented
9104e7f9df2SMichael S. Tsirkin	  in the HPET spec, revision 1.
911506f1d07SSam Ravnborg
912506f1d07SSam Ravnborg	  You can safely choose Y here.  However, HPET will only be
913506f1d07SSam Ravnborg	  activated if the platform and the BIOS support this feature.
914506f1d07SSam Ravnborg	  Otherwise the 8254 will be used for timing services.
915506f1d07SSam Ravnborg
916506f1d07SSam Ravnborg	  Choose N to continue using the legacy 8254 timer.
917506f1d07SSam Ravnborg
918506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC
9193c2362e6SHarvey Harrison	def_bool y
9203228e1dcSAnand K Mistry	depends on HPET_TIMER && (RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
921506f1d07SSam Ravnborg
9226a108a14SDavid Rientjes# Mark as expert because too many people got it wrong.
923506f1d07SSam Ravnborg# The code disables itself when not needed.
9247ae9392cSThomas Petazzoniconfig DMI
9257ae9392cSThomas Petazzoni	default y
926cf074402SArd Biesheuvel	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
9276a108a14SDavid Rientjes	bool "Enable DMI scanning" if EXPERT
928a7f7f624SMasahiro Yamada	help
9297ae9392cSThomas Petazzoni	  Enabled scanning of DMI to identify machine quirks. Say Y
9307ae9392cSThomas Petazzoni	  here unless you have verified that your setup is not
9317ae9392cSThomas Petazzoni	  affected by entries in the DMI blacklist. Required by PNP
9327ae9392cSThomas Petazzoni	  BIOS code.
9337ae9392cSThomas Petazzoni
934506f1d07SSam Ravnborgconfig GART_IOMMU
93538901f1cSAndi Kleen	bool "Old AMD GART IOMMU support"
9362f9237d4SChristoph Hellwig	select DMA_OPS
937a4ce5a48SChristoph Hellwig	select IOMMU_HELPER
938506f1d07SSam Ravnborg	select SWIOTLB
93923ac4ae8SAndreas Herrmann	depends on X86_64 && PCI && AMD_NB
940a7f7f624SMasahiro Yamada	help
941ced3c42cSIngo Molnar	  Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
942ced3c42cSIngo Molnar	  GART based hardware IOMMUs.
943ced3c42cSIngo Molnar
944ced3c42cSIngo Molnar	  The GART supports full DMA access for devices with 32-bit access
945ced3c42cSIngo Molnar	  limitations, on systems with more than 3 GB. This is usually needed
946ced3c42cSIngo Molnar	  for USB, sound, many IDE/SATA chipsets and some other devices.
947ced3c42cSIngo Molnar
948ced3c42cSIngo Molnar	  Newer systems typically have a modern AMD IOMMU, supported via
949ced3c42cSIngo Molnar	  the CONFIG_AMD_IOMMU=y config option.
950ced3c42cSIngo Molnar
951ced3c42cSIngo Molnar	  In normal configurations this driver is only active when needed:
952ced3c42cSIngo Molnar	  there's more than 3 GB of memory and the system contains a
953ced3c42cSIngo Molnar	  32-bit limited device.
954ced3c42cSIngo Molnar
955ced3c42cSIngo Molnar	  If unsure, say Y.
956506f1d07SSam Ravnborg
9578b766b0fSMichal Suchanekconfig BOOT_VESA_SUPPORT
9588b766b0fSMichal Suchanek	bool
9598b766b0fSMichal Suchanek	help
9608b766b0fSMichal Suchanek	  If true, at least one selected framebuffer driver can take advantage
9618b766b0fSMichal Suchanek	  of VESA video modes set at an early boot stage via the vga= parameter.
9628b766b0fSMichal Suchanek
9631184dc2fSMike Travisconfig MAXSMP
964ddb0c5a6SSamuel Thibault	bool "Enable Maximum number of SMP Processors and NUMA Nodes"
9656ea30386SKees Cook	depends on X86_64 && SMP && DEBUG_KERNEL
96636f5101aSMike Travis	select CPUMASK_OFFSTACK
967a7f7f624SMasahiro Yamada	help
968ddb0c5a6SSamuel Thibault	  Enable maximum number of CPUS and NUMA Nodes for this architecture.
9691184dc2fSMike Travis	  If unsure, say N.
970506f1d07SSam Ravnborg
971aec6487eSIngo Molnar#
972aec6487eSIngo Molnar# The maximum number of CPUs supported:
973aec6487eSIngo Molnar#
974aec6487eSIngo Molnar# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
975aec6487eSIngo Molnar# and which can be configured interactively in the
976aec6487eSIngo Molnar# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
977aec6487eSIngo Molnar#
978aec6487eSIngo Molnar# The ranges are different on 32-bit and 64-bit kernels, depending on
979aec6487eSIngo Molnar# hardware capabilities and scalability features of the kernel.
980aec6487eSIngo Molnar#
981aec6487eSIngo Molnar# ( If MAXSMP is enabled we just use the highest possible value and disable
982aec6487eSIngo Molnar#   interactive configuration. )
983aec6487eSIngo Molnar#
984a0d0bb4dSRandy Dunlap
985aec6487eSIngo Molnarconfig NR_CPUS_RANGE_BEGIN
986a0d0bb4dSRandy Dunlap	int
987aec6487eSIngo Molnar	default NR_CPUS_RANGE_END if MAXSMP
988a0d0bb4dSRandy Dunlap	default    1 if !SMP
989a0d0bb4dSRandy Dunlap	default    2
990a0d0bb4dSRandy Dunlap
991aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END
992a0d0bb4dSRandy Dunlap	int
993a0d0bb4dSRandy Dunlap	depends on X86_32
994aec6487eSIngo Molnar	default   64 if  SMP &&  X86_BIGSMP
995aec6487eSIngo Molnar	default    8 if  SMP && !X86_BIGSMP
996a0d0bb4dSRandy Dunlap	default    1 if !SMP
997a0d0bb4dSRandy Dunlap
998aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END
999a0d0bb4dSRandy Dunlap	int
1000a0d0bb4dSRandy Dunlap	depends on X86_64
10011edae1aeSScott Wood	default 8192 if  SMP && CPUMASK_OFFSTACK
10021edae1aeSScott Wood	default  512 if  SMP && !CPUMASK_OFFSTACK
1003a0d0bb4dSRandy Dunlap	default    1 if !SMP
1004aec6487eSIngo Molnar
1005aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT
1006aec6487eSIngo Molnar	int
1007aec6487eSIngo Molnar	depends on X86_32
1008aec6487eSIngo Molnar	default   32 if  X86_BIGSMP
1009aec6487eSIngo Molnar	default    8 if  SMP
1010aec6487eSIngo Molnar	default    1 if !SMP
1011aec6487eSIngo Molnar
1012aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT
1013aec6487eSIngo Molnar	int
1014aec6487eSIngo Molnar	depends on X86_64
1015a0d0bb4dSRandy Dunlap	default 8192 if  MAXSMP
1016a0d0bb4dSRandy Dunlap	default   64 if  SMP
1017aec6487eSIngo Molnar	default    1 if !SMP
1018a0d0bb4dSRandy Dunlap
1019506f1d07SSam Ravnborgconfig NR_CPUS
102036f5101aSMike Travis	int "Maximum number of CPUs" if SMP && !MAXSMP
1021aec6487eSIngo Molnar	range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
1022aec6487eSIngo Molnar	default NR_CPUS_DEFAULT
1023a7f7f624SMasahiro Yamada	help
1024506f1d07SSam Ravnborg	  This allows you to specify the maximum number of CPUs which this
1025bb61ccc7SJosh Boyer	  kernel will support.  If CPUMASK_OFFSTACK is enabled, the maximum
1026cad14bb9SKirill A. Shutemov	  supported value is 8192, otherwise the maximum value is 512.  The
1027506f1d07SSam Ravnborg	  minimum value which makes sense is 2.
1028506f1d07SSam Ravnborg
1029aec6487eSIngo Molnar	  This is purely to save memory: each supported CPU adds about 8KB
1030aec6487eSIngo Molnar	  to the kernel image.
1031506f1d07SSam Ravnborg
103266558b73STim Chenconfig SCHED_CLUSTER
103366558b73STim Chen	bool "Cluster scheduler support"
103466558b73STim Chen	depends on SMP
103566558b73STim Chen	default y
103666558b73STim Chen	help
103766558b73STim Chen	  Cluster scheduler support improves the CPU scheduler's decision
103866558b73STim Chen	  making when dealing with machines that have clusters of CPUs.
103966558b73STim Chen	  Cluster usually means a couple of CPUs which are placed closely
104066558b73STim Chen	  by sharing mid-level caches, last-level cache tags or internal
104166558b73STim Chen	  busses.
104266558b73STim Chen
1043506f1d07SSam Ravnborgconfig SCHED_SMT
1044dbe73364SThomas Gleixner	def_bool y if SMP
1045506f1d07SSam Ravnborg
1046506f1d07SSam Ravnborgconfig SCHED_MC
10473c2362e6SHarvey Harrison	def_bool y
10483c2362e6SHarvey Harrison	prompt "Multi-core scheduler support"
1049c8e56d20SBorislav Petkov	depends on SMP
1050a7f7f624SMasahiro Yamada	help
1051506f1d07SSam Ravnborg	  Multi-core scheduler support improves the CPU scheduler's decision
1052506f1d07SSam Ravnborg	  making when dealing with multi-core CPU chips at a cost of slightly
1053506f1d07SSam Ravnborg	  increased overhead in some places. If unsure say N here.
1054506f1d07SSam Ravnborg
1055de966cf4STim Chenconfig SCHED_MC_PRIO
1056de966cf4STim Chen	bool "CPU core priorities scheduler support"
10570a21fc12SIngo Molnar	depends on SCHED_MC && CPU_SUP_INTEL
10580a21fc12SIngo Molnar	select X86_INTEL_PSTATE
10590a21fc12SIngo Molnar	select CPU_FREQ
1060de966cf4STim Chen	default y
1061a7f7f624SMasahiro Yamada	help
1062de966cf4STim Chen	  Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1063de966cf4STim Chen	  core ordering determined at manufacturing time, which allows
1064de966cf4STim Chen	  certain cores to reach higher turbo frequencies (when running
1065de966cf4STim Chen	  single threaded workloads) than others.
1066de966cf4STim Chen
1067de966cf4STim Chen	  Enabling this kernel feature teaches the scheduler about
1068de966cf4STim Chen	  the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1069de966cf4STim Chen	  scheduler's CPU selection logic accordingly, so that higher
1070de966cf4STim Chen	  overall system performance can be achieved.
1071de966cf4STim Chen
1072de966cf4STim Chen	  This feature will have no effect on CPUs without this feature.
1073de966cf4STim Chen
1074de966cf4STim Chen	  If unsure say Y here.
10755e76b2abSTim Chen
107630b8b006SThomas Gleixnerconfig UP_LATE_INIT
107730b8b006SThomas Gleixner	def_bool y
1078ba360f88SThomas Gleixner	depends on !SMP && X86_LOCAL_APIC
107930b8b006SThomas Gleixner
1080506f1d07SSam Ravnborgconfig X86_UP_APIC
108150849eefSJan Beulich	bool "Local APIC support on uniprocessors" if !PCI_MSI
108250849eefSJan Beulich	default PCI_MSI
108338a1dfdaSBryan O'Donoghue	depends on X86_32 && !SMP && !X86_32_NON_STANDARD
1084a7f7f624SMasahiro Yamada	help
1085506f1d07SSam Ravnborg	  A local APIC (Advanced Programmable Interrupt Controller) is an
1086506f1d07SSam Ravnborg	  integrated interrupt controller in the CPU. If you have a single-CPU
1087506f1d07SSam Ravnborg	  system which has a processor with a local APIC, you can say Y here to
1088506f1d07SSam Ravnborg	  enable and use it. If you say Y here even though your machine doesn't
1089506f1d07SSam Ravnborg	  have a local APIC, then the kernel will still run with no slowdown at
1090506f1d07SSam Ravnborg	  all. The local APIC supports CPU-generated self-interrupts (timer,
1091506f1d07SSam Ravnborg	  performance counters), and the NMI watchdog which detects hard
1092506f1d07SSam Ravnborg	  lockups.
1093506f1d07SSam Ravnborg
1094506f1d07SSam Ravnborgconfig X86_UP_IOAPIC
1095506f1d07SSam Ravnborg	bool "IO-APIC support on uniprocessors"
1096506f1d07SSam Ravnborg	depends on X86_UP_APIC
1097a7f7f624SMasahiro Yamada	help
1098506f1d07SSam Ravnborg	  An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1099506f1d07SSam Ravnborg	  SMP-capable replacement for PC-style interrupt controllers. Most
1100506f1d07SSam Ravnborg	  SMP systems and many recent uniprocessor systems have one.
1101506f1d07SSam Ravnborg
1102506f1d07SSam Ravnborg	  If you have a single-CPU system with an IO-APIC, you can say Y here
1103506f1d07SSam Ravnborg	  to use it. If you say Y here even though your machine doesn't have
1104506f1d07SSam Ravnborg	  an IO-APIC, then the kernel will still run with no slowdown at all.
1105506f1d07SSam Ravnborg
1106506f1d07SSam Ravnborgconfig X86_LOCAL_APIC
11073c2362e6SHarvey Harrison	def_bool y
11080dbc6078SThomas Petazzoni	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
1109b5dc8e6cSJiang Liu	select IRQ_DOMAIN_HIERARCHY
1110506f1d07SSam Ravnborg
1111506f1d07SSam Ravnborgconfig X86_IO_APIC
1112b1da1e71SJan Beulich	def_bool y
1113b1da1e71SJan Beulich	depends on X86_LOCAL_APIC || X86_UP_IOAPIC
1114506f1d07SSam Ravnborg
111541b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS
111641b9eb26SStefan Assmann	bool "Reroute for broken boot IRQs"
111741b9eb26SStefan Assmann	depends on X86_IO_APIC
1118a7f7f624SMasahiro Yamada	help
111941b9eb26SStefan Assmann	  This option enables a workaround that fixes a source of
112041b9eb26SStefan Assmann	  spurious interrupts. This is recommended when threaded
112141b9eb26SStefan Assmann	  interrupt handling is used on systems where the generation of
112241b9eb26SStefan Assmann	  superfluous "boot interrupts" cannot be disabled.
112341b9eb26SStefan Assmann
112441b9eb26SStefan Assmann	  Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
112541b9eb26SStefan Assmann	  entry in the chipset's IO-APIC is masked (as, e.g. the RT
112641b9eb26SStefan Assmann	  kernel does during interrupt handling). On chipsets where this
112741b9eb26SStefan Assmann	  boot IRQ generation cannot be disabled, this workaround keeps
112841b9eb26SStefan Assmann	  the original IRQ line masked so that only the equivalent "boot
112941b9eb26SStefan Assmann	  IRQ" is delivered to the CPUs. The workaround also tells the
113041b9eb26SStefan Assmann	  kernel to set up the IRQ handler on the boot IRQ line. In this
113141b9eb26SStefan Assmann	  way only one interrupt is delivered to the kernel. Otherwise
113241b9eb26SStefan Assmann	  the spurious second interrupt may cause the kernel to bring
113341b9eb26SStefan Assmann	  down (vital) interrupt lines.
113441b9eb26SStefan Assmann
113541b9eb26SStefan Assmann	  Only affects "broken" chipsets. Interrupt sharing may be
113641b9eb26SStefan Assmann	  increased on these systems.
113741b9eb26SStefan Assmann
1138506f1d07SSam Ravnborgconfig X86_MCE
1139bab9bc65SAndi Kleen	bool "Machine Check / overheating reporting"
1140648ed940SChen, Gong	select GENERIC_ALLOCATOR
1141e57dbaf7SBorislav Petkov	default y
1142a7f7f624SMasahiro Yamada	help
1143bab9bc65SAndi Kleen	  Machine Check support allows the processor to notify the
1144bab9bc65SAndi Kleen	  kernel if it detects a problem (e.g. overheating, data corruption).
1145506f1d07SSam Ravnborg	  The action the kernel takes depends on the severity of the problem,
1146bab9bc65SAndi Kleen	  ranging from warning messages to halting the machine.
11474efc0670SAndi Kleen
11485de97c9fSTony Luckconfig X86_MCELOG_LEGACY
11495de97c9fSTony Luck	bool "Support for deprecated /dev/mcelog character device"
11505de97c9fSTony Luck	depends on X86_MCE
1151a7f7f624SMasahiro Yamada	help
11525de97c9fSTony Luck	  Enable support for /dev/mcelog which is needed by the old mcelog
11535de97c9fSTony Luck	  userspace logging daemon. Consider switching to the new generation
11545de97c9fSTony Luck	  rasdaemon solution.
11555de97c9fSTony Luck
1156506f1d07SSam Ravnborgconfig X86_MCE_INTEL
11573c2362e6SHarvey Harrison	def_bool y
11583c2362e6SHarvey Harrison	prompt "Intel MCE features"
1159c1ebf835SAndi Kleen	depends on X86_MCE && X86_LOCAL_APIC
1160a7f7f624SMasahiro Yamada	help
1161506f1d07SSam Ravnborg	  Additional support for intel specific MCE features such as
1162506f1d07SSam Ravnborg	  the thermal monitor.
1163506f1d07SSam Ravnborg
1164506f1d07SSam Ravnborgconfig X86_MCE_AMD
11653c2362e6SHarvey Harrison	def_bool y
11663c2362e6SHarvey Harrison	prompt "AMD MCE features"
1167f5382de9SYazen Ghannam	depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
1168a7f7f624SMasahiro Yamada	help
1169506f1d07SSam Ravnborg	  Additional support for AMD specific MCE features such as
1170506f1d07SSam Ravnborg	  the DRAM Error Threshold.
1171506f1d07SSam Ravnborg
11724efc0670SAndi Kleenconfig X86_ANCIENT_MCE
11736fc108a0SJan Beulich	bool "Support for old Pentium 5 / WinChip machine checks"
1174c31d9633SAndi Kleen	depends on X86_32 && X86_MCE
1175a7f7f624SMasahiro Yamada	help
11764efc0670SAndi Kleen	  Include support for machine check handling on old Pentium 5 or WinChip
11775065a706SMasanari Iida	  systems. These typically need to be enabled explicitly on the command
11784efc0670SAndi Kleen	  line.
11794efc0670SAndi Kleen
1180b2762686SAndi Kleenconfig X86_MCE_THRESHOLD
1181b2762686SAndi Kleen	depends on X86_MCE_AMD || X86_MCE_INTEL
11826fc108a0SJan Beulich	def_bool y
1183b2762686SAndi Kleen
1184ea149b36SAndi Kleenconfig X86_MCE_INJECT
1185bc8e80d5SBorislav Petkov	depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
1186ea149b36SAndi Kleen	tristate "Machine check injector support"
1187a7f7f624SMasahiro Yamada	help
1188ea149b36SAndi Kleen	  Provide support for injecting machine checks for testing purposes.
1189ea149b36SAndi Kleen	  If you don't know what a machine check is and you don't do kernel
1190ea149b36SAndi Kleen	  QA it is safe to say n.
1191ea149b36SAndi Kleen
119207dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig"
1193e633c65aSKan Liang
11945aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86
11951e642812SIngo Molnar	bool "Legacy VM86 support"
1196506f1d07SSam Ravnborg	depends on X86_32
1197a7f7f624SMasahiro Yamada	help
11985aef51c3SAndy Lutomirski	  This option allows user programs to put the CPU into V8086
11995aef51c3SAndy Lutomirski	  mode, which is an 80286-era approximation of 16-bit real mode.
12005aef51c3SAndy Lutomirski
12015aef51c3SAndy Lutomirski	  Some very old versions of X and/or vbetool require this option
12025aef51c3SAndy Lutomirski	  for user mode setting.  Similarly, DOSEMU will use it if
12035aef51c3SAndy Lutomirski	  available to accelerate real mode DOS programs.  However, any
12045aef51c3SAndy Lutomirski	  recent version of DOSEMU, X, or vbetool should be fully
12055aef51c3SAndy Lutomirski	  functional even without kernel VM86 support, as they will all
12061e642812SIngo Molnar	  fall back to software emulation. Nevertheless, if you are using
12071e642812SIngo Molnar	  a 16-bit DOS program where 16-bit performance matters, vm86
12081e642812SIngo Molnar	  mode might be faster than emulation and you might want to
12091e642812SIngo Molnar	  enable this option.
12105aef51c3SAndy Lutomirski
12111e642812SIngo Molnar	  Note that any app that works on a 64-bit kernel is unlikely to
12121e642812SIngo Molnar	  need this option, as 64-bit kernels don't, and can't, support
12131e642812SIngo Molnar	  V8086 mode. This option is also unrelated to 16-bit protected
12141e642812SIngo Molnar	  mode and is not needed to run most 16-bit programs under Wine.
12155aef51c3SAndy Lutomirski
12161e642812SIngo Molnar	  Enabling this option increases the complexity of the kernel
12171e642812SIngo Molnar	  and slows down exception handling a tiny bit.
12185aef51c3SAndy Lutomirski
12191e642812SIngo Molnar	  If unsure, say N here.
12205aef51c3SAndy Lutomirski
12215aef51c3SAndy Lutomirskiconfig VM86
12225aef51c3SAndy Lutomirski	bool
12235aef51c3SAndy Lutomirski	default X86_LEGACY_VM86
122434273f41SH. Peter Anvin
122534273f41SH. Peter Anvinconfig X86_16BIT
122634273f41SH. Peter Anvin	bool "Enable support for 16-bit segments" if EXPERT
122734273f41SH. Peter Anvin	default y
1228a5b9e5a2SAndy Lutomirski	depends on MODIFY_LDT_SYSCALL
1229a7f7f624SMasahiro Yamada	help
123034273f41SH. Peter Anvin	  This option is required by programs like Wine to run 16-bit
123134273f41SH. Peter Anvin	  protected mode legacy code on x86 processors.  Disabling
123234273f41SH. Peter Anvin	  this option saves about 300 bytes on i386, or around 6K text
123334273f41SH. Peter Anvin	  plus 16K runtime memory on x86-64,
123434273f41SH. Peter Anvin
123534273f41SH. Peter Anvinconfig X86_ESPFIX32
123634273f41SH. Peter Anvin	def_bool y
123734273f41SH. Peter Anvin	depends on X86_16BIT && X86_32
1238506f1d07SSam Ravnborg
1239197725deSH. Peter Anvinconfig X86_ESPFIX64
1240197725deSH. Peter Anvin	def_bool y
124134273f41SH. Peter Anvin	depends on X86_16BIT && X86_64
1242506f1d07SSam Ravnborg
12431ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION
12441ad83c85SAndy Lutomirski	bool "Enable vsyscall emulation" if EXPERT
12451ad83c85SAndy Lutomirski	default y
12461ad83c85SAndy Lutomirski	depends on X86_64
1247a7f7f624SMasahiro Yamada	help
12481ad83c85SAndy Lutomirski	  This enables emulation of the legacy vsyscall page.  Disabling
12491ad83c85SAndy Lutomirski	  it is roughly equivalent to booting with vsyscall=none, except
12501ad83c85SAndy Lutomirski	  that it will also disable the helpful warning if a program
12511ad83c85SAndy Lutomirski	  tries to use a vsyscall.  With this option set to N, offending
12521ad83c85SAndy Lutomirski	  programs will just segfault, citing addresses of the form
12531ad83c85SAndy Lutomirski	  0xffffffffff600?00.
12541ad83c85SAndy Lutomirski
12551ad83c85SAndy Lutomirski	  This option is required by many programs built before 2013, and
12561ad83c85SAndy Lutomirski	  care should be used even with newer programs if set to N.
12571ad83c85SAndy Lutomirski
12581ad83c85SAndy Lutomirski	  Disabling this option saves about 7K of kernel size and
12591ad83c85SAndy Lutomirski	  possibly 4K of additional runtime pagetable memory.
12601ad83c85SAndy Lutomirski
1261111e7b15SThomas Gleixnerconfig X86_IOPL_IOPERM
1262111e7b15SThomas Gleixner	bool "IOPERM and IOPL Emulation"
1263a24ca997SThomas Gleixner	default y
1264a7f7f624SMasahiro Yamada	help
1265111e7b15SThomas Gleixner	  This enables the ioperm() and iopl() syscalls which are necessary
1266111e7b15SThomas Gleixner	  for legacy applications.
1267111e7b15SThomas Gleixner
1268c8137aceSThomas Gleixner	  Legacy IOPL support is an overbroad mechanism which allows user
1269c8137aceSThomas Gleixner	  space aside of accessing all 65536 I/O ports also to disable
1270c8137aceSThomas Gleixner	  interrupts. To gain this access the caller needs CAP_SYS_RAWIO
1271c8137aceSThomas Gleixner	  capabilities and permission from potentially active security
1272c8137aceSThomas Gleixner	  modules.
1273c8137aceSThomas Gleixner
1274c8137aceSThomas Gleixner	  The emulation restricts the functionality of the syscall to
1275c8137aceSThomas Gleixner	  only allowing the full range I/O port access, but prevents the
1276a24ca997SThomas Gleixner	  ability to disable interrupts from user space which would be
1277a24ca997SThomas Gleixner	  granted if the hardware IOPL mechanism would be used.
1278c8137aceSThomas Gleixner
1279506f1d07SSam Ravnborgconfig TOSHIBA
1280506f1d07SSam Ravnborg	tristate "Toshiba Laptop support"
1281506f1d07SSam Ravnborg	depends on X86_32
1282a7f7f624SMasahiro Yamada	help
1283506f1d07SSam Ravnborg	  This adds a driver to safely access the System Management Mode of
1284506f1d07SSam Ravnborg	  the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1285506f1d07SSam Ravnborg	  not work on models with a Phoenix BIOS. The System Management Mode
1286506f1d07SSam Ravnborg	  is used to set the BIOS and power saving options on Toshiba portables.
1287506f1d07SSam Ravnborg
1288506f1d07SSam Ravnborg	  For information on utilities to make use of this driver see the
1289506f1d07SSam Ravnborg	  Toshiba Linux utilities web site at:
1290506f1d07SSam Ravnborg	  <http://www.buzzard.org.uk/toshiba/>.
1291506f1d07SSam Ravnborg
1292506f1d07SSam Ravnborg	  Say Y if you intend to run this kernel on a Toshiba portable.
1293506f1d07SSam Ravnborg	  Say N otherwise.
1294506f1d07SSam Ravnborg
1295506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS
12969ba16087SJan Beulich	bool "Enable X86 board specific fixups for reboot"
12979ba16087SJan Beulich	depends on X86_32
1298a7f7f624SMasahiro Yamada	help
1299506f1d07SSam Ravnborg	  This enables chipset and/or board specific fixups to be done
1300506f1d07SSam Ravnborg	  in order to get reboot to work correctly. This is only needed on
1301506f1d07SSam Ravnborg	  some combinations of hardware and BIOS. The symptom, for which
1302506f1d07SSam Ravnborg	  this config is intended, is when reboot ends with a stalled/hung
1303506f1d07SSam Ravnborg	  system.
1304506f1d07SSam Ravnborg
1305506f1d07SSam Ravnborg	  Currently, the only fixup is for the Geode machines using
13065e3a77e9SFlorian Fainelli	  CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1307506f1d07SSam Ravnborg
1308506f1d07SSam Ravnborg	  Say Y if you want to enable the fixup. Currently, it's safe to
1309506f1d07SSam Ravnborg	  enable this option even if you don't need it.
1310506f1d07SSam Ravnborg	  Say N otherwise.
1311506f1d07SSam Ravnborg
1312506f1d07SSam Ravnborgconfig MICROCODE
13139a2bc335SBorislav Petkov	bool "CPU microcode loading support"
13149a2bc335SBorislav Petkov	default y
131580030e3dSBorislav Petkov	depends on CPU_SUP_AMD || CPU_SUP_INTEL
1316a7f7f624SMasahiro Yamada	help
1317506f1d07SSam Ravnborg	  If you say Y here, you will be able to update the microcode on
13185f9c01aaSBorislav Petkov	  Intel and AMD processors. The Intel support is for the IA32 family,
13195f9c01aaSBorislav Petkov	  e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
13205f9c01aaSBorislav Petkov	  AMD support is for families 0x10 and later. You will obviously need
13215f9c01aaSBorislav Petkov	  the actual microcode binary data itself which is not shipped with
13225f9c01aaSBorislav Petkov	  the Linux kernel.
1323506f1d07SSam Ravnborg
13245f9c01aaSBorislav Petkov	  The preferred method to load microcode from a detached initrd is described
1325ff61f079SJonathan Corbet	  in Documentation/arch/x86/microcode.rst. For that you need to enable
13265f9c01aaSBorislav Petkov	  CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
13275f9c01aaSBorislav Petkov	  initrd for microcode blobs.
1328506f1d07SSam Ravnborg
1329c508c46eSBenjamin Gilbert	  In addition, you can build the microcode into the kernel. For that you
1330c508c46eSBenjamin Gilbert	  need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1331c508c46eSBenjamin Gilbert	  config option.
1332506f1d07SSam Ravnborg
13338d86f390SPeter Orubaconfig MICROCODE_INTEL
1334e43f6e67SBorislav Petkov	bool "Intel microcode loading support"
13359c55d99eSBorislav Petkov	depends on CPU_SUP_INTEL && MICROCODE
13368d86f390SPeter Oruba	default MICROCODE
1337a7f7f624SMasahiro Yamada	help
13388d86f390SPeter Oruba	  This options enables microcode patch loading support for Intel
13398d86f390SPeter Oruba	  processors.
13408d86f390SPeter Oruba
1341b8989db9SAlan	  For the current Intel microcode data package go to
1342b8989db9SAlan	  <https://downloadcenter.intel.com> and search for
1343b8989db9SAlan	  'Linux Processor Microcode Data File'.
13448d86f390SPeter Oruba
134580cc9f10SPeter Orubaconfig MICROCODE_AMD
1346e43f6e67SBorislav Petkov	bool "AMD microcode loading support"
13479c55d99eSBorislav Petkov	depends on CPU_SUP_AMD && MICROCODE
1348a7f7f624SMasahiro Yamada	help
134980cc9f10SPeter Oruba	  If you select this option, microcode patch loading support for AMD
135080cc9f10SPeter Oruba	  processors will be enabled.
135180cc9f10SPeter Oruba
1352a77a94f8SBorislav Petkovconfig MICROCODE_LATE_LOADING
1353a77a94f8SBorislav Petkov	bool "Late microcode loading (DANGEROUS)"
1354c02f48e0SBorislav Petkov	default n
1355506f1d07SSam Ravnborg	depends on MICROCODE
1356a7f7f624SMasahiro Yamada	help
1357a77a94f8SBorislav Petkov	  Loading microcode late, when the system is up and executing instructions
1358a77a94f8SBorislav Petkov	  is a tricky business and should be avoided if possible. Just the sequence
1359a77a94f8SBorislav Petkov	  of synchronizing all cores and SMT threads is one fragile dance which does
1360a77a94f8SBorislav Petkov	  not guarantee that cores might not softlock after the loading. Therefore,
1361a77a94f8SBorislav Petkov	  use this at your own risk. Late loading taints the kernel too.
1362506f1d07SSam Ravnborg
1363506f1d07SSam Ravnborgconfig X86_MSR
1364506f1d07SSam Ravnborg	tristate "/dev/cpu/*/msr - Model-specific register support"
1365a7f7f624SMasahiro Yamada	help
1366506f1d07SSam Ravnborg	  This device gives privileged processes access to the x86
1367506f1d07SSam Ravnborg	  Model-Specific Registers (MSRs).  It is a character device with
1368506f1d07SSam Ravnborg	  major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1369506f1d07SSam Ravnborg	  MSR accesses are directed to a specific CPU on multi-processor
1370506f1d07SSam Ravnborg	  systems.
1371506f1d07SSam Ravnborg
1372506f1d07SSam Ravnborgconfig X86_CPUID
1373506f1d07SSam Ravnborg	tristate "/dev/cpu/*/cpuid - CPU information support"
1374a7f7f624SMasahiro Yamada	help
1375506f1d07SSam Ravnborg	  This device gives processes access to the x86 CPUID instruction to
1376506f1d07SSam Ravnborg	  be executed on a specific processor.  It is a character device
1377506f1d07SSam Ravnborg	  with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1378506f1d07SSam Ravnborg	  /dev/cpu/31/cpuid.
1379506f1d07SSam Ravnborg
1380506f1d07SSam Ravnborgchoice
1381506f1d07SSam Ravnborg	prompt "High Memory Support"
13826fc108a0SJan Beulich	default HIGHMEM4G
1383506f1d07SSam Ravnborg	depends on X86_32
1384506f1d07SSam Ravnborg
1385506f1d07SSam Ravnborgconfig NOHIGHMEM
1386506f1d07SSam Ravnborg	bool "off"
1387a7f7f624SMasahiro Yamada	help
1388506f1d07SSam Ravnborg	  Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1389506f1d07SSam Ravnborg	  However, the address space of 32-bit x86 processors is only 4
1390506f1d07SSam Ravnborg	  Gigabytes large. That means that, if you have a large amount of
1391506f1d07SSam Ravnborg	  physical memory, not all of it can be "permanently mapped" by the
1392506f1d07SSam Ravnborg	  kernel. The physical memory that's not permanently mapped is called
1393506f1d07SSam Ravnborg	  "high memory".
1394506f1d07SSam Ravnborg
1395506f1d07SSam Ravnborg	  If you are compiling a kernel which will never run on a machine with
1396506f1d07SSam Ravnborg	  more than 1 Gigabyte total physical RAM, answer "off" here (default
1397506f1d07SSam Ravnborg	  choice and suitable for most users). This will result in a "3GB/1GB"
1398506f1d07SSam Ravnborg	  split: 3GB are mapped so that each process sees a 3GB virtual memory
1399506f1d07SSam Ravnborg	  space and the remaining part of the 4GB virtual memory space is used
1400506f1d07SSam Ravnborg	  by the kernel to permanently map as much physical memory as
1401506f1d07SSam Ravnborg	  possible.
1402506f1d07SSam Ravnborg
1403506f1d07SSam Ravnborg	  If the machine has between 1 and 4 Gigabytes physical RAM, then
1404506f1d07SSam Ravnborg	  answer "4GB" here.
1405506f1d07SSam Ravnborg
1406506f1d07SSam Ravnborg	  If more than 4 Gigabytes is used then answer "64GB" here. This
1407506f1d07SSam Ravnborg	  selection turns Intel PAE (Physical Address Extension) mode on.
1408506f1d07SSam Ravnborg	  PAE implements 3-level paging on IA32 processors. PAE is fully
1409506f1d07SSam Ravnborg	  supported by Linux, PAE mode is implemented on all recent Intel
1410506f1d07SSam Ravnborg	  processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1411506f1d07SSam Ravnborg	  then the kernel will not boot on CPUs that don't support PAE!
1412506f1d07SSam Ravnborg
1413506f1d07SSam Ravnborg	  The actual amount of total physical memory will either be
1414506f1d07SSam Ravnborg	  auto detected or can be forced by using a kernel command line option
1415506f1d07SSam Ravnborg	  such as "mem=256M". (Try "man bootparam" or see the documentation of
1416506f1d07SSam Ravnborg	  your boot loader (lilo or loadlin) about how to pass options to the
1417506f1d07SSam Ravnborg	  kernel at boot time.)
1418506f1d07SSam Ravnborg
1419506f1d07SSam Ravnborg	  If unsure, say "off".
1420506f1d07SSam Ravnborg
1421506f1d07SSam Ravnborgconfig HIGHMEM4G
1422506f1d07SSam Ravnborg	bool "4GB"
1423a7f7f624SMasahiro Yamada	help
1424506f1d07SSam Ravnborg	  Select this if you have a 32-bit processor and between 1 and 4
1425506f1d07SSam Ravnborg	  gigabytes of physical RAM.
1426506f1d07SSam Ravnborg
1427506f1d07SSam Ravnborgconfig HIGHMEM64G
1428506f1d07SSam Ravnborg	bool "64GB"
1429225bac2dSLukas Bulwahn	depends on !M486SX && !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !MWINCHIP3D && !MK6
1430506f1d07SSam Ravnborg	select X86_PAE
1431a7f7f624SMasahiro Yamada	help
1432506f1d07SSam Ravnborg	  Select this if you have a 32-bit processor and more than 4
1433506f1d07SSam Ravnborg	  gigabytes of physical RAM.
1434506f1d07SSam Ravnborg
1435506f1d07SSam Ravnborgendchoice
1436506f1d07SSam Ravnborg
1437506f1d07SSam Ravnborgchoice
14386a108a14SDavid Rientjes	prompt "Memory split" if EXPERT
1439506f1d07SSam Ravnborg	default VMSPLIT_3G
1440506f1d07SSam Ravnborg	depends on X86_32
1441a7f7f624SMasahiro Yamada	help
1442506f1d07SSam Ravnborg	  Select the desired split between kernel and user memory.
1443506f1d07SSam Ravnborg
1444506f1d07SSam Ravnborg	  If the address range available to the kernel is less than the
1445506f1d07SSam Ravnborg	  physical memory installed, the remaining memory will be available
1446506f1d07SSam Ravnborg	  as "high memory". Accessing high memory is a little more costly
1447506f1d07SSam Ravnborg	  than low memory, as it needs to be mapped into the kernel first.
1448506f1d07SSam Ravnborg	  Note that increasing the kernel address space limits the range
1449506f1d07SSam Ravnborg	  available to user programs, making the address space there
1450506f1d07SSam Ravnborg	  tighter.  Selecting anything other than the default 3G/1G split
1451506f1d07SSam Ravnborg	  will also likely make your kernel incompatible with binary-only
1452506f1d07SSam Ravnborg	  kernel modules.
1453506f1d07SSam Ravnborg
1454506f1d07SSam Ravnborg	  If you are not absolutely sure what you are doing, leave this
1455506f1d07SSam Ravnborg	  option alone!
1456506f1d07SSam Ravnborg
1457506f1d07SSam Ravnborg	config VMSPLIT_3G
1458506f1d07SSam Ravnborg		bool "3G/1G user/kernel split"
1459506f1d07SSam Ravnborg	config VMSPLIT_3G_OPT
1460506f1d07SSam Ravnborg		depends on !X86_PAE
1461506f1d07SSam Ravnborg		bool "3G/1G user/kernel split (for full 1G low memory)"
1462506f1d07SSam Ravnborg	config VMSPLIT_2G
1463506f1d07SSam Ravnborg		bool "2G/2G user/kernel split"
1464506f1d07SSam Ravnborg	config VMSPLIT_2G_OPT
1465506f1d07SSam Ravnborg		depends on !X86_PAE
1466506f1d07SSam Ravnborg		bool "2G/2G user/kernel split (for full 2G low memory)"
1467506f1d07SSam Ravnborg	config VMSPLIT_1G
1468506f1d07SSam Ravnborg		bool "1G/3G user/kernel split"
1469506f1d07SSam Ravnborgendchoice
1470506f1d07SSam Ravnborg
1471506f1d07SSam Ravnborgconfig PAGE_OFFSET
1472506f1d07SSam Ravnborg	hex
1473506f1d07SSam Ravnborg	default 0xB0000000 if VMSPLIT_3G_OPT
1474506f1d07SSam Ravnborg	default 0x80000000 if VMSPLIT_2G
1475506f1d07SSam Ravnborg	default 0x78000000 if VMSPLIT_2G_OPT
1476506f1d07SSam Ravnborg	default 0x40000000 if VMSPLIT_1G
1477506f1d07SSam Ravnborg	default 0xC0000000
1478506f1d07SSam Ravnborg	depends on X86_32
1479506f1d07SSam Ravnborg
1480506f1d07SSam Ravnborgconfig HIGHMEM
14813c2362e6SHarvey Harrison	def_bool y
1482506f1d07SSam Ravnborg	depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1483506f1d07SSam Ravnborg
1484506f1d07SSam Ravnborgconfig X86_PAE
14859ba16087SJan Beulich	bool "PAE (Physical Address Extension) Support"
1486506f1d07SSam Ravnborg	depends on X86_32 && !HIGHMEM4G
1487d4a451d5SChristoph Hellwig	select PHYS_ADDR_T_64BIT
14889d99c712SChristian Melki	select SWIOTLB
1489a7f7f624SMasahiro Yamada	help
1490506f1d07SSam Ravnborg	  PAE is required for NX support, and furthermore enables
1491506f1d07SSam Ravnborg	  larger swapspace support for non-overcommit purposes. It
1492506f1d07SSam Ravnborg	  has the cost of more pagetable lookup overhead, and also
1493506f1d07SSam Ravnborg	  consumes more pagetable space per process.
1494506f1d07SSam Ravnborg
149577ef56e4SKirill A. Shutemovconfig X86_5LEVEL
149677ef56e4SKirill A. Shutemov	bool "Enable 5-level page tables support"
149718ec1eafSKirill A. Shutemov	default y
1498eedb92abSKirill A. Shutemov	select DYNAMIC_MEMORY_LAYOUT
1499162434e7SKirill A. Shutemov	select SPARSEMEM_VMEMMAP
150077ef56e4SKirill A. Shutemov	depends on X86_64
1501a7f7f624SMasahiro Yamada	help
150277ef56e4SKirill A. Shutemov	  5-level paging enables access to larger address space:
150377ef56e4SKirill A. Shutemov	  up to 128 PiB of virtual address space and 4 PiB of
150477ef56e4SKirill A. Shutemov	  physical address space.
150577ef56e4SKirill A. Shutemov
150677ef56e4SKirill A. Shutemov	  It will be supported by future Intel CPUs.
150777ef56e4SKirill A. Shutemov
15086657fca0SKirill A. Shutemov	  A kernel with the option enabled can be booted on machines that
15096657fca0SKirill A. Shutemov	  support 4- or 5-level paging.
151077ef56e4SKirill A. Shutemov
1511ff61f079SJonathan Corbet	  See Documentation/arch/x86/x86_64/5level-paging.rst for more
151277ef56e4SKirill A. Shutemov	  information.
151377ef56e4SKirill A. Shutemov
151477ef56e4SKirill A. Shutemov	  Say N if unsure.
151577ef56e4SKirill A. Shutemov
151610971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES
1517e5008abeSLuis R. Rodriguez	def_bool y
15182e1da13fSVlastimil Babka	depends on X86_64
1519a7f7f624SMasahiro Yamada	help
152010971ab2SIngo Molnar	  Certain kernel features effectively disable kernel
152110971ab2SIngo Molnar	  linear 1 GB mappings (even if the CPU otherwise
152210971ab2SIngo Molnar	  supports them), so don't confuse the user by printing
152310971ab2SIngo Molnar	  that we have them enabled.
15249e899816SNick Piggin
15255c280cf6SThomas Gleixnerconfig X86_CPA_STATISTICS
15265c280cf6SThomas Gleixner	bool "Enable statistic for Change Page Attribute"
15275c280cf6SThomas Gleixner	depends on DEBUG_FS
1528a7f7f624SMasahiro Yamada	help
1529b75baaf3SIngo Molnar	  Expose statistics about the Change Page Attribute mechanism, which
1530a943245aSColin Ian King	  helps to determine the effectiveness of preserving large and huge
15315c280cf6SThomas Gleixner	  page mappings when mapping protections are changed.
15325c280cf6SThomas Gleixner
153320f07a04SKirill A. Shutemovconfig X86_MEM_ENCRYPT
153420f07a04SKirill A. Shutemov	select ARCH_HAS_FORCE_DMA_UNENCRYPTED
153520f07a04SKirill A. Shutemov	select DYNAMIC_PHYSICAL_MASK
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
15416c321179STom Lendacky	depends on EFI_STUB
154282fef0adSDavid Rientjes	select DMA_COHERENT_POOL
1543ce9084baSArd Biesheuvel	select ARCH_USE_MEMREMAP_PROT
1544597cfe48SJoerg Roedel	select INSTRUCTION_DECODER
1545aa5a4611STom Lendacky	select ARCH_HAS_CC_PLATFORM
154620f07a04SKirill A. Shutemov	select X86_MEM_ENCRYPT
15476c321179STom Lendacky	select UNACCEPTED_MEMORY
1548a7f7f624SMasahiro Yamada	help
15497744ccdbSTom Lendacky	  Say yes to enable support for the encryption of system memory.
15507744ccdbSTom Lendacky	  This requires an AMD processor that supports Secure Memory
15517744ccdbSTom Lendacky	  Encryption (SME).
15527744ccdbSTom Lendacky
15537744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
15547744ccdbSTom Lendacky	bool "Activate AMD Secure Memory Encryption (SME) by default"
15557744ccdbSTom Lendacky	depends on AMD_MEM_ENCRYPT
1556a7f7f624SMasahiro Yamada	help
15577744ccdbSTom Lendacky	  Say yes to have system memory encrypted by default if running on
15587744ccdbSTom Lendacky	  an AMD processor that supports Secure Memory Encryption (SME).
15597744ccdbSTom Lendacky
15607744ccdbSTom Lendacky	  If set to Y, then the encryption of system memory can be
15617744ccdbSTom Lendacky	  deactivated with the mem_encrypt=off command line option.
15627744ccdbSTom Lendacky
15637744ccdbSTom Lendacky	  If set to N, then the encryption of system memory can be
15647744ccdbSTom Lendacky	  activated with the mem_encrypt=on command line option.
15657744ccdbSTom Lendacky
1566506f1d07SSam Ravnborg# Common NUMA Features
1567506f1d07SSam Ravnborgconfig NUMA
1568e133f6eaSRandy Dunlap	bool "NUMA Memory Allocation and Scheduler Support"
1569506f1d07SSam Ravnborg	depends on SMP
1570b5660ba7SH. Peter Anvin	depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1571b5660ba7SH. Peter Anvin	default y if X86_BIGSMP
15727ecd19cfSKefeng Wang	select USE_PERCPU_NUMA_NODE_ID
1573a7f7f624SMasahiro Yamada	help
1574e133f6eaSRandy Dunlap	  Enable NUMA (Non-Uniform Memory Access) support.
1575fd51b2d7SKOSAKI Motohiro
1576506f1d07SSam Ravnborg	  The kernel will try to allocate memory used by a CPU on the
1577506f1d07SSam Ravnborg	  local memory controller of the CPU and add some more
1578506f1d07SSam Ravnborg	  NUMA awareness to the kernel.
1579506f1d07SSam Ravnborg
1580c280ea5eSIngo Molnar	  For 64-bit this is recommended if the system is Intel Core i7
1581fd51b2d7SKOSAKI Motohiro	  (or later), AMD Opteron, or EM64T NUMA.
1582fd51b2d7SKOSAKI Motohiro
1583b5660ba7SH. Peter Anvin	  For 32-bit this is only needed if you boot a 32-bit
15847cf6c945SDavid Rientjes	  kernel on a 64-bit NUMA platform.
1585fd51b2d7SKOSAKI Motohiro
1586fd51b2d7SKOSAKI Motohiro	  Otherwise, you should say N.
1587506f1d07SSam Ravnborg
1588eec1d4faSHans Rosenfeldconfig AMD_NUMA
15893c2362e6SHarvey Harrison	def_bool y
15903c2362e6SHarvey Harrison	prompt "Old style AMD Opteron NUMA detection"
15915da0ef9aSTejun Heo	depends on X86_64 && NUMA && PCI
1592a7f7f624SMasahiro Yamada	help
1593eec1d4faSHans Rosenfeld	  Enable AMD NUMA node topology detection.  You should say Y here if
1594eec1d4faSHans Rosenfeld	  you have a multi processor AMD system. This uses an old method to
1595eec1d4faSHans Rosenfeld	  read the NUMA configuration directly from the builtin Northbridge
1596eec1d4faSHans Rosenfeld	  of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1597eec1d4faSHans Rosenfeld	  which also takes priority if both are compiled in.
1598506f1d07SSam Ravnborg
1599506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA
16003c2362e6SHarvey Harrison	def_bool y
16013c2362e6SHarvey Harrison	prompt "ACPI NUMA detection"
1602506f1d07SSam Ravnborg	depends on X86_64 && NUMA && ACPI && PCI
1603506f1d07SSam Ravnborg	select ACPI_NUMA
1604a7f7f624SMasahiro Yamada	help
1605506f1d07SSam Ravnborg	  Enable ACPI SRAT based node topology detection.
1606506f1d07SSam Ravnborg
1607506f1d07SSam Ravnborgconfig NUMA_EMU
1608506f1d07SSam Ravnborg	bool "NUMA emulation"
16091b7e03efSTejun Heo	depends on NUMA
1610a7f7f624SMasahiro Yamada	help
1611506f1d07SSam Ravnborg	  Enable NUMA emulation. A flat machine will be split
1612506f1d07SSam Ravnborg	  into virtual nodes when booted with "numa=fake=N", where N is the
1613506f1d07SSam Ravnborg	  number of nodes. This is only useful for debugging.
1614506f1d07SSam Ravnborg
1615506f1d07SSam Ravnborgconfig NODES_SHIFT
1616d25e26b6SLinus Torvalds	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
161751591e31SDavid Rientjes	range 1 10
161851591e31SDavid Rientjes	default "10" if MAXSMP
1619506f1d07SSam Ravnborg	default "6" if X86_64
1620506f1d07SSam Ravnborg	default "3"
1621a9ee6cf5SMike Rapoport	depends on NUMA
1622a7f7f624SMasahiro Yamada	help
16231184dc2fSMike Travis	  Specify the maximum number of NUMA Nodes available on the target
1624692105b8SMatt LaPlante	  system.  Increases memory reserved to accommodate various tables.
1625506f1d07SSam Ravnborg
1626506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE
1627506f1d07SSam Ravnborg	def_bool y
16283b16651fSTejun Heo	depends on X86_32 && !NUMA
1629506f1d07SSam Ravnborg
1630506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE
1631506f1d07SSam Ravnborg	def_bool y
16326ea30386SKees Cook	depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1633506f1d07SSam Ravnborg	select SPARSEMEM_STATIC if X86_32
1634506f1d07SSam Ravnborg	select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1635506f1d07SSam Ravnborg
16363b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT
16376ad57f7fSMike Rapoport	def_bool X86_64 || (NUMA && X86_32)
16383b16651fSTejun Heo
1639506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL
1640506f1d07SSam Ravnborg	def_bool y
16414eda2bc3SDavid Hildenbrand	depends on ARCH_SPARSEMEM_ENABLE && ARCH_FLATMEM_ENABLE
1642506f1d07SSam Ravnborg
1643506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE
1644a0842b70SToshi Kani	bool "Enable sysfs memory/probe interface"
16455c11f00bSDavid Hildenbrand	depends on MEMORY_HOTPLUG
1646a0842b70SToshi Kani	help
1647a0842b70SToshi Kani	  This option enables a sysfs memory/probe interface for testing.
1648cb1aaebeSMauro Carvalho Chehab	  See Documentation/admin-guide/mm/memory-hotplug.rst for more information.
1649a0842b70SToshi Kani	  If you are unsure how to answer this question, answer N.
1650506f1d07SSam Ravnborg
16513b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT
16523b16651fSTejun Heo	def_bool y
16533b16651fSTejun Heo	depends on X86_64 && PROC_KCORE
16543b16651fSTejun Heo
1655a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE
1656a29815a3SAvi Kivity	hex
1657a29815a3SAvi Kivity	default 0 if X86_32
1658a29815a3SAvi Kivity	default 0xdead000000000000 if X86_64
1659a29815a3SAvi Kivity
16607a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE
16617a67832cSDan Williams	bool
16627a67832cSDan Williams
1663ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY
16647a67832cSDan Williams	tristate "Support non-standard NVDIMMs and ADR protected memory"
16659f53f9faSDan Williams	depends on PHYS_ADDR_T_64BIT
16669f53f9faSDan Williams	depends on BLK_DEV
16677a67832cSDan Williams	select X86_PMEM_LEGACY_DEVICE
16687b27a862SDan Williams	select NUMA_KEEP_MEMINFO if NUMA
16699f53f9faSDan Williams	select LIBNVDIMM
1670ec776ef6SChristoph Hellwig	help
1671ec776ef6SChristoph Hellwig	  Treat memory marked using the non-standard e820 type of 12 as used
1672ec776ef6SChristoph Hellwig	  by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1673ec776ef6SChristoph Hellwig	  The kernel will offer these regions to the 'pmem' driver so
1674ec776ef6SChristoph Hellwig	  they can be used for persistent storage.
1675ec776ef6SChristoph Hellwig
1676ec776ef6SChristoph Hellwig	  Say Y if unsure.
1677ec776ef6SChristoph Hellwig
1678506f1d07SSam Ravnborgconfig HIGHPTE
1679506f1d07SSam Ravnborg	bool "Allocate 3rd-level pagetables from highmem"
16806fc108a0SJan Beulich	depends on HIGHMEM
1681a7f7f624SMasahiro Yamada	help
1682506f1d07SSam Ravnborg	  The VM uses one page table entry for each page of physical memory.
1683506f1d07SSam Ravnborg	  For systems with a lot of RAM, this can be wasteful of precious
1684506f1d07SSam Ravnborg	  low memory.  Setting this option will put user-space page table
1685506f1d07SSam Ravnborg	  entries in high memory.
1686506f1d07SSam Ravnborg
16879f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION
16889f077871SJeremy Fitzhardinge	bool "Check for low memory corruption"
1689a7f7f624SMasahiro Yamada	help
16909f077871SJeremy Fitzhardinge	  Periodically check for memory corruption in low memory, which
16919f077871SJeremy Fitzhardinge	  is suspected to be caused by BIOS.  Even when enabled in the
16929f077871SJeremy Fitzhardinge	  configuration, it is disabled at runtime.  Enable it by
16939f077871SJeremy Fitzhardinge	  setting "memory_corruption_check=1" on the kernel command
16949f077871SJeremy Fitzhardinge	  line.  By default it scans the low 64k of memory every 60
16959f077871SJeremy Fitzhardinge	  seconds; see the memory_corruption_check_size and
16969f077871SJeremy Fitzhardinge	  memory_corruption_check_period parameters in
16978c27ceffSMauro Carvalho Chehab	  Documentation/admin-guide/kernel-parameters.rst to adjust this.
16989f077871SJeremy Fitzhardinge
16999f077871SJeremy Fitzhardinge	  When enabled with the default parameters, this option has
17009f077871SJeremy Fitzhardinge	  almost no overhead, as it reserves a relatively small amount
17019f077871SJeremy Fitzhardinge	  of memory and scans it infrequently.  It both detects corruption
17029f077871SJeremy Fitzhardinge	  and prevents it from affecting the running system.
17039f077871SJeremy Fitzhardinge
17049f077871SJeremy Fitzhardinge	  It is, however, intended as a diagnostic tool; if repeatable
17059f077871SJeremy Fitzhardinge	  BIOS-originated corruption always affects the same memory,
17069f077871SJeremy Fitzhardinge	  you can use memmap= to prevent the kernel from using that
17079f077871SJeremy Fitzhardinge	  memory.
17089f077871SJeremy Fitzhardinge
1709c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1710c885df50SJeremy Fitzhardinge	bool "Set the default setting of memory_corruption_check"
1711c885df50SJeremy Fitzhardinge	depends on X86_CHECK_BIOS_CORRUPTION
1712c885df50SJeremy Fitzhardinge	default y
1713a7f7f624SMasahiro Yamada	help
1714c885df50SJeremy Fitzhardinge	  Set whether the default state of memory_corruption_check is
1715c885df50SJeremy Fitzhardinge	  on or off.
1716c885df50SJeremy Fitzhardinge
1717506f1d07SSam Ravnborgconfig MATH_EMULATION
1718506f1d07SSam Ravnborg	bool
1719a5b9e5a2SAndy Lutomirski	depends on MODIFY_LDT_SYSCALL
172087d6021bSArnd Bergmann	prompt "Math emulation" if X86_32 && (M486SX || MELAN)
1721a7f7f624SMasahiro Yamada	help
1722506f1d07SSam Ravnborg	  Linux can emulate a math coprocessor (used for floating point
1723506f1d07SSam Ravnborg	  operations) if you don't have one. 486DX and Pentium processors have
1724506f1d07SSam Ravnborg	  a math coprocessor built in, 486SX and 386 do not, unless you added
1725506f1d07SSam Ravnborg	  a 487DX or 387, respectively. (The messages during boot time can
1726506f1d07SSam Ravnborg	  give you some hints here ["man dmesg"].) Everyone needs either a
1727506f1d07SSam Ravnborg	  coprocessor or this emulation.
1728506f1d07SSam Ravnborg
1729506f1d07SSam Ravnborg	  If you don't have a math coprocessor, you need to say Y here; if you
1730506f1d07SSam Ravnborg	  say Y here even though you have a coprocessor, the coprocessor will
1731506f1d07SSam Ravnborg	  be used nevertheless. (This behavior can be changed with the kernel
1732506f1d07SSam Ravnborg	  command line option "no387", which comes handy if your coprocessor
1733506f1d07SSam Ravnborg	  is broken. Try "man bootparam" or see the documentation of your boot
1734506f1d07SSam Ravnborg	  loader (lilo or loadlin) about how to pass options to the kernel at
1735506f1d07SSam Ravnborg	  boot time.) This means that it is a good idea to say Y here if you
1736506f1d07SSam Ravnborg	  intend to use this kernel on different machines.
1737506f1d07SSam Ravnborg
1738506f1d07SSam Ravnborg	  More information about the internals of the Linux math coprocessor
1739506f1d07SSam Ravnborg	  emulation can be found in <file:arch/x86/math-emu/README>.
1740506f1d07SSam Ravnborg
1741506f1d07SSam Ravnborg	  If you are not sure, say Y; apart from resulting in a 66 KB bigger
1742506f1d07SSam Ravnborg	  kernel, it won't hurt.
1743506f1d07SSam Ravnborg
1744506f1d07SSam Ravnborgconfig MTRR
17456fc108a0SJan Beulich	def_bool y
17466a108a14SDavid Rientjes	prompt "MTRR (Memory Type Range Register) support" if EXPERT
1747a7f7f624SMasahiro Yamada	help
1748506f1d07SSam Ravnborg	  On Intel P6 family processors (Pentium Pro, Pentium II and later)
1749506f1d07SSam Ravnborg	  the Memory Type Range Registers (MTRRs) may be used to control
1750506f1d07SSam Ravnborg	  processor access to memory ranges. This is most useful if you have
1751506f1d07SSam Ravnborg	  a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1752506f1d07SSam Ravnborg	  allows bus write transfers to be combined into a larger transfer
1753506f1d07SSam Ravnborg	  before bursting over the PCI/AGP bus. This can increase performance
1754506f1d07SSam Ravnborg	  of image write operations 2.5 times or more. Saying Y here creates a
1755506f1d07SSam Ravnborg	  /proc/mtrr file which may be used to manipulate your processor's
1756506f1d07SSam Ravnborg	  MTRRs. Typically the X server should use this.
1757506f1d07SSam Ravnborg
1758506f1d07SSam Ravnborg	  This code has a reasonably generic interface so that similar
1759506f1d07SSam Ravnborg	  control registers on other processors can be easily supported
1760506f1d07SSam Ravnborg	  as well:
1761506f1d07SSam Ravnborg
1762506f1d07SSam Ravnborg	  The Cyrix 6x86, 6x86MX and M II processors have Address Range
1763506f1d07SSam Ravnborg	  Registers (ARRs) which provide a similar functionality to MTRRs. For
1764506f1d07SSam Ravnborg	  these, the ARRs are used to emulate the MTRRs.
1765506f1d07SSam Ravnborg	  The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1766506f1d07SSam Ravnborg	  MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1767506f1d07SSam Ravnborg	  write-combining. All of these processors are supported by this code
1768506f1d07SSam Ravnborg	  and it makes sense to say Y here if you have one of them.
1769506f1d07SSam Ravnborg
1770506f1d07SSam Ravnborg	  Saying Y here also fixes a problem with buggy SMP BIOSes which only
1771506f1d07SSam Ravnborg	  set the MTRRs for the boot CPU and not for the secondary CPUs. This
1772506f1d07SSam Ravnborg	  can lead to all sorts of problems, so it's good to say Y here.
1773506f1d07SSam Ravnborg
1774506f1d07SSam Ravnborg	  You can safely say Y even if your machine doesn't have MTRRs, you'll
1775506f1d07SSam Ravnborg	  just add about 9 KB to your kernel.
1776506f1d07SSam Ravnborg
1777ff61f079SJonathan Corbet	  See <file:Documentation/arch/x86/mtrr.rst> for more information.
1778506f1d07SSam Ravnborg
177995ffa243SYinghai Luconfig MTRR_SANITIZER
17802ffb3501SYinghai Lu	def_bool y
178195ffa243SYinghai Lu	prompt "MTRR cleanup support"
178295ffa243SYinghai Lu	depends on MTRR
1783a7f7f624SMasahiro Yamada	help
1784aba3728cSThomas Gleixner	  Convert MTRR layout from continuous to discrete, so X drivers can
1785aba3728cSThomas Gleixner	  add writeback entries.
178695ffa243SYinghai Lu
1787aba3728cSThomas Gleixner	  Can be disabled with disable_mtrr_cleanup on the kernel command line.
1788692105b8SMatt LaPlante	  The largest mtrr entry size for a continuous block can be set with
1789aba3728cSThomas Gleixner	  mtrr_chunk_size.
179095ffa243SYinghai Lu
17912ffb3501SYinghai Lu	  If unsure, say Y.
179295ffa243SYinghai Lu
179395ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT
1794f5098d62SYinghai Lu	int "MTRR cleanup enable value (0-1)"
1795f5098d62SYinghai Lu	range 0 1
1796f5098d62SYinghai Lu	default "0"
179795ffa243SYinghai Lu	depends on MTRR_SANITIZER
1798a7f7f624SMasahiro Yamada	help
1799f5098d62SYinghai Lu	  Enable mtrr cleanup default value
180095ffa243SYinghai Lu
180112031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
180212031a62SYinghai Lu	int "MTRR cleanup spare reg num (0-7)"
180312031a62SYinghai Lu	range 0 7
180412031a62SYinghai Lu	default "1"
180512031a62SYinghai Lu	depends on MTRR_SANITIZER
1806a7f7f624SMasahiro Yamada	help
180712031a62SYinghai Lu	  mtrr cleanup spare entries default, it can be changed via
1808aba3728cSThomas Gleixner	  mtrr_spare_reg_nr=N on the kernel command line.
180912031a62SYinghai Lu
18102e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT
18116fc108a0SJan Beulich	def_bool y
18126a108a14SDavid Rientjes	prompt "x86 PAT support" if EXPERT
18132a8a2719SIngo Molnar	depends on MTRR
1814a7f7f624SMasahiro Yamada	help
18152e5d9c85Svenkatesh.pallipadi@intel.com	  Use PAT attributes to setup page level cache control.
1816042b78e4SVenki Pallipadi
18172e5d9c85Svenkatesh.pallipadi@intel.com	  PATs are the modern equivalents of MTRRs and are much more
18182e5d9c85Svenkatesh.pallipadi@intel.com	  flexible than MTRRs.
18192e5d9c85Svenkatesh.pallipadi@intel.com
18202e5d9c85Svenkatesh.pallipadi@intel.com	  Say N here if you see bootup problems (boot crash, boot hang,
1821042b78e4SVenki Pallipadi	  spontaneous reboots) or a non-working video driver.
18222e5d9c85Svenkatesh.pallipadi@intel.com
18232e5d9c85Svenkatesh.pallipadi@intel.com	  If unsure, say Y.
18242e5d9c85Svenkatesh.pallipadi@intel.com
182546cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED
182646cf98cdSVenkatesh Pallipadi	def_bool y
182746cf98cdSVenkatesh Pallipadi	depends on X86_PAT
182846cf98cdSVenkatesh Pallipadi
1829b971880fSBabu Mogerconfig X86_UMIP
1830796ebc81SRicardo Neri	def_bool y
1831b971880fSBabu Moger	prompt "User Mode Instruction Prevention" if EXPERT
1832a7f7f624SMasahiro Yamada	help
1833b971880fSBabu Moger	  User Mode Instruction Prevention (UMIP) is a security feature in
1834b971880fSBabu Moger	  some x86 processors. If enabled, a general protection fault is
1835b971880fSBabu Moger	  issued if the SGDT, SLDT, SIDT, SMSW or STR instructions are
1836b971880fSBabu Moger	  executed in user mode. These instructions unnecessarily expose
1837b971880fSBabu Moger	  information about the hardware state.
1838796ebc81SRicardo Neri
1839796ebc81SRicardo Neri	  The vast majority of applications do not use these instructions.
1840796ebc81SRicardo Neri	  For the very few that do, software emulation is provided in
1841796ebc81SRicardo Neri	  specific cases in protected and virtual-8086 modes. Emulated
1842796ebc81SRicardo Neri	  results are dummy.
1843aa35f896SRicardo Neri
1844156ff4a5SPeter Zijlstraconfig CC_HAS_IBT
1845156ff4a5SPeter Zijlstra	# GCC >= 9 and binutils >= 2.29
1846156ff4a5SPeter Zijlstra	# Retpoline check to work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93654
1847156ff4a5SPeter Zijlstra	# Clang/LLVM >= 14
1848262448f3SNathan Chancellor	# https://github.com/llvm/llvm-project/commit/e0b89df2e0f0130881bf6c39bf31d7f6aac00e0f
1849262448f3SNathan Chancellor	# https://github.com/llvm/llvm-project/commit/dfcf69770bc522b9e411c66454934a37c1f35332
1850156ff4a5SPeter Zijlstra	def_bool ((CC_IS_GCC && $(cc-option, -fcf-protection=branch -mindirect-branch-register)) || \
1851262448f3SNathan Chancellor		  (CC_IS_CLANG && CLANG_VERSION >= 140000)) && \
1852156ff4a5SPeter Zijlstra		  $(as-instr,endbr64)
1853156ff4a5SPeter Zijlstra
1854156ff4a5SPeter Zijlstraconfig X86_KERNEL_IBT
1855156ff4a5SPeter Zijlstra	prompt "Indirect Branch Tracking"
18564fd5f70cSKees Cook	def_bool y
185703f16cd0SJosh Poimboeuf	depends on X86_64 && CC_HAS_IBT && HAVE_OBJTOOL
1858f6a2c2b2SNathan Chancellor	# https://github.com/llvm/llvm-project/commit/9d7001eba9c4cb311e03cd8cdc231f9e579f2d0f
1859f6a2c2b2SNathan Chancellor	depends on !LD_IS_LLD || LLD_VERSION >= 140000
186003f16cd0SJosh Poimboeuf	select OBJTOOL
1861156ff4a5SPeter Zijlstra	help
1862156ff4a5SPeter Zijlstra	  Build the kernel with support for Indirect Branch Tracking, a
1863156ff4a5SPeter Zijlstra	  hardware support course-grain forward-edge Control Flow Integrity
1864156ff4a5SPeter Zijlstra	  protection. It enforces that all indirect calls must land on
1865156ff4a5SPeter Zijlstra	  an ENDBR instruction, as such, the compiler will instrument the
1866156ff4a5SPeter Zijlstra	  code with them to make this happen.
1867156ff4a5SPeter Zijlstra
1868ed53a0d9SPeter Zijlstra	  In addition to building the kernel with IBT, seal all functions that
18694cdfc11bSNur Hussein	  are not indirect call targets, avoiding them ever becoming one.
1870ed53a0d9SPeter Zijlstra
1871ed53a0d9SPeter Zijlstra	  This requires LTO like objtool runs and will slow down the build. It
1872ed53a0d9SPeter Zijlstra	  does significantly reduce the number of ENDBR instructions in the
1873ed53a0d9SPeter Zijlstra	  kernel image.
1874ed53a0d9SPeter Zijlstra
187535e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS
187638f3e775SBabu Moger	prompt "Memory Protection Keys"
187735e97790SDave Hansen	def_bool y
1878284244a9SDave Hansen	# Note: only available in 64-bit mode
187938f3e775SBabu Moger	depends on X86_64 && (CPU_SUP_INTEL || CPU_SUP_AMD)
188052c8e601SIngo Molnar	select ARCH_USES_HIGH_VMA_FLAGS
188152c8e601SIngo Molnar	select ARCH_HAS_PKEYS
1882a7f7f624SMasahiro Yamada	help
1883284244a9SDave Hansen	  Memory Protection Keys provides a mechanism for enforcing
1884284244a9SDave Hansen	  page-based protections, but without requiring modification of the
1885284244a9SDave Hansen	  page tables when an application changes protection domains.
1886284244a9SDave Hansen
18871eecbcdcSMauro Carvalho Chehab	  For details, see Documentation/core-api/protection-keys.rst
1888284244a9SDave Hansen
1889284244a9SDave Hansen	  If unsure, say y.
189035e97790SDave Hansen
1891db616173SMichal Hockochoice
1892db616173SMichal Hocko	prompt "TSX enable mode"
1893db616173SMichal Hocko	depends on CPU_SUP_INTEL
1894db616173SMichal Hocko	default X86_INTEL_TSX_MODE_OFF
1895db616173SMichal Hocko	help
1896db616173SMichal Hocko	  Intel's TSX (Transactional Synchronization Extensions) feature
1897db616173SMichal Hocko	  allows to optimize locking protocols through lock elision which
1898db616173SMichal Hocko	  can lead to a noticeable performance boost.
1899db616173SMichal Hocko
1900db616173SMichal Hocko	  On the other hand it has been shown that TSX can be exploited
1901db616173SMichal Hocko	  to form side channel attacks (e.g. TAA) and chances are there
1902db616173SMichal Hocko	  will be more of those attacks discovered in the future.
1903db616173SMichal Hocko
1904db616173SMichal Hocko	  Therefore TSX is not enabled by default (aka tsx=off). An admin
1905db616173SMichal Hocko	  might override this decision by tsx=on the command line parameter.
1906db616173SMichal Hocko	  Even with TSX enabled, the kernel will attempt to enable the best
1907db616173SMichal Hocko	  possible TAA mitigation setting depending on the microcode available
1908db616173SMichal Hocko	  for the particular machine.
1909db616173SMichal Hocko
1910db616173SMichal Hocko	  This option allows to set the default tsx mode between tsx=on, =off
1911db616173SMichal Hocko	  and =auto. See Documentation/admin-guide/kernel-parameters.txt for more
1912db616173SMichal Hocko	  details.
1913db616173SMichal Hocko
1914db616173SMichal Hocko	  Say off if not sure, auto if TSX is in use but it should be used on safe
1915db616173SMichal Hocko	  platforms or on if TSX is in use and the security aspect of tsx is not
1916db616173SMichal Hocko	  relevant.
1917db616173SMichal Hocko
1918db616173SMichal Hockoconfig X86_INTEL_TSX_MODE_OFF
1919db616173SMichal Hocko	bool "off"
1920db616173SMichal Hocko	help
1921db616173SMichal Hocko	  TSX is disabled if possible - equals to tsx=off command line parameter.
1922db616173SMichal Hocko
1923db616173SMichal Hockoconfig X86_INTEL_TSX_MODE_ON
1924db616173SMichal Hocko	bool "on"
1925db616173SMichal Hocko	help
1926db616173SMichal Hocko	  TSX is always enabled on TSX capable HW - equals the tsx=on command
1927db616173SMichal Hocko	  line parameter.
1928db616173SMichal Hocko
1929db616173SMichal Hockoconfig X86_INTEL_TSX_MODE_AUTO
1930db616173SMichal Hocko	bool "auto"
1931db616173SMichal Hocko	help
1932db616173SMichal Hocko	  TSX is enabled on TSX capable HW that is believed to be safe against
1933db616173SMichal Hocko	  side channel attacks- equals the tsx=auto command line parameter.
1934db616173SMichal Hockoendchoice
1935db616173SMichal Hocko
1936e7e05452SSean Christophersonconfig X86_SGX
1937e7e05452SSean Christopherson	bool "Software Guard eXtensions (SGX)"
1938b8d1d163SDaniel Sneddon	depends on X86_64 && CPU_SUP_INTEL && X86_X2APIC
1939e7e05452SSean Christopherson	depends on CRYPTO=y
1940e7e05452SSean Christopherson	depends on CRYPTO_SHA256=y
1941e7e05452SSean Christopherson	select MMU_NOTIFIER
1942901ddbb9SJarkko Sakkinen	select NUMA_KEEP_MEMINFO if NUMA
194340e0e784STony Luck	select XARRAY_MULTI
1944e7e05452SSean Christopherson	help
1945e7e05452SSean Christopherson	  Intel(R) Software Guard eXtensions (SGX) is a set of CPU instructions
1946e7e05452SSean Christopherson	  that can be used by applications to set aside private regions of code
1947e7e05452SSean Christopherson	  and data, referred to as enclaves. An enclave's private memory can
1948e7e05452SSean Christopherson	  only be accessed by code running within the enclave. Accesses from
1949e7e05452SSean Christopherson	  outside the enclave, including other enclaves, are disallowed by
1950e7e05452SSean Christopherson	  hardware.
1951e7e05452SSean Christopherson
1952e7e05452SSean Christopherson	  If unsure, say N.
1953e7e05452SSean Christopherson
1954506f1d07SSam Ravnborgconfig EFI
19559ba16087SJan Beulich	bool "EFI runtime service support"
19565b83683fSHuang, Ying	depends on ACPI
1957f6ce5002SSergey Vlasov	select UCS2_STRING
1958022ee6c5SArd Biesheuvel	select EFI_RUNTIME_WRAPPERS
19591ff2fc02STom Lendacky	select ARCH_USE_MEMREMAP_PROT
1960a7f7f624SMasahiro Yamada	help
19618b2cb7a8SHuang, Ying	  This enables the kernel to use EFI runtime services that are
1962506f1d07SSam Ravnborg	  available (such as the EFI variable services).
1963506f1d07SSam Ravnborg
19648b2cb7a8SHuang, Ying	  This option is only useful on systems that have EFI firmware.
19658b2cb7a8SHuang, Ying	  In addition, you should use the latest ELILO loader available
19668b2cb7a8SHuang, Ying	  at <http://elilo.sourceforge.net> in order to take advantage
19678b2cb7a8SHuang, Ying	  of EFI runtime services. However, even with this option, the
19688b2cb7a8SHuang, Ying	  resultant kernel should continue to boot on existing non-EFI
19698b2cb7a8SHuang, Ying	  platforms.
1970506f1d07SSam Ravnborg
1971291f3632SMatt Flemingconfig EFI_STUB
1972291f3632SMatt Fleming	bool "EFI stub support"
1973c6dbd3e5SPeter Zijlstra	depends on EFI
19747b2a583aSMatt Fleming	select RELOCATABLE
1975a7f7f624SMasahiro Yamada	help
1976291f3632SMatt Fleming	  This kernel feature allows a bzImage to be loaded directly
1977291f3632SMatt Fleming	  by EFI firmware without the use of a bootloader.
1978291f3632SMatt Fleming
19794f4cfa6cSMauro Carvalho Chehab	  See Documentation/admin-guide/efi-stub.rst for more information.
19800c759662SMatt Fleming
1981cc3fdda2SArd Biesheuvelconfig EFI_HANDOVER_PROTOCOL
1982cc3fdda2SArd Biesheuvel	bool "EFI handover protocol (DEPRECATED)"
1983cc3fdda2SArd Biesheuvel	depends on EFI_STUB
1984cc3fdda2SArd Biesheuvel	default y
1985cc3fdda2SArd Biesheuvel	help
1986cc3fdda2SArd Biesheuvel	  Select this in order to include support for the deprecated EFI
1987cc3fdda2SArd Biesheuvel	  handover protocol, which defines alternative entry points into the
1988cc3fdda2SArd Biesheuvel	  EFI stub.  This is a practice that has no basis in the UEFI
1989cc3fdda2SArd Biesheuvel	  specification, and requires a priori knowledge on the part of the
1990cc3fdda2SArd Biesheuvel	  bootloader about Linux/x86 specific ways of passing the command line
1991cc3fdda2SArd Biesheuvel	  and initrd, and where in memory those assets may be loaded.
1992cc3fdda2SArd Biesheuvel
1993cc3fdda2SArd Biesheuvel	  If in doubt, say Y. Even though the corresponding support is not
1994cc3fdda2SArd Biesheuvel	  present in upstream GRUB or other bootloaders, most distros build
1995cc3fdda2SArd Biesheuvel	  GRUB with numerous downstream patches applied, and may rely on the
1996cc3fdda2SArd Biesheuvel	  handover protocol as as result.
1997cc3fdda2SArd Biesheuvel
19987d453eeeSMatt Flemingconfig EFI_MIXED
19997d453eeeSMatt Fleming	bool "EFI mixed-mode support"
20007d453eeeSMatt Fleming	depends on EFI_STUB && X86_64
2001a7f7f624SMasahiro Yamada	help
20027d453eeeSMatt Fleming	  Enabling this feature allows a 64-bit kernel to be booted
20037d453eeeSMatt Fleming	  on a 32-bit firmware, provided that your CPU supports 64-bit
20047d453eeeSMatt Fleming	  mode.
20057d453eeeSMatt Fleming
20067d453eeeSMatt Fleming	  Note that it is not possible to boot a mixed-mode enabled
20077d453eeeSMatt Fleming	  kernel via the EFI boot stub - a bootloader that supports
20087d453eeeSMatt Fleming	  the EFI handover protocol must be used.
20097d453eeeSMatt Fleming
20107d453eeeSMatt Fleming	  If unsure, say N.
20117d453eeeSMatt Fleming
20124059ba65SArd Biesheuvelconfig EFI_FAKE_MEMMAP
20134059ba65SArd Biesheuvel	bool "Enable EFI fake memory map"
20144059ba65SArd Biesheuvel	depends on EFI
20154059ba65SArd Biesheuvel	help
20164059ba65SArd Biesheuvel	  Saying Y here will enable "efi_fake_mem" boot option.  By specifying
20174059ba65SArd Biesheuvel	  this parameter, you can add arbitrary attribute to specific memory
20184059ba65SArd Biesheuvel	  range by updating original (firmware provided) EFI memmap.  This is
20194059ba65SArd Biesheuvel	  useful for debugging of EFI memmap related feature, e.g., Address
20204059ba65SArd Biesheuvel	  Range Mirroring feature.
20214059ba65SArd Biesheuvel
20224059ba65SArd Biesheuvelconfig EFI_MAX_FAKE_MEM
20234059ba65SArd Biesheuvel	int "maximum allowable number of ranges in efi_fake_mem boot option"
20244059ba65SArd Biesheuvel	depends on EFI_FAKE_MEMMAP
20254059ba65SArd Biesheuvel	range 1 128
20264059ba65SArd Biesheuvel	default 8
20274059ba65SArd Biesheuvel	help
20284059ba65SArd Biesheuvel	  Maximum allowable number of ranges in efi_fake_mem boot option.
20294059ba65SArd Biesheuvel	  Ranges can be set up to this value using comma-separated list.
20304059ba65SArd Biesheuvel	  The default value is 8.
20314059ba65SArd Biesheuvel
20321fff234dSArd Biesheuvelconfig EFI_RUNTIME_MAP
20331fff234dSArd Biesheuvel	bool "Export EFI runtime maps to sysfs" if EXPERT
20341fff234dSArd Biesheuvel	depends on EFI
20351fff234dSArd Biesheuvel	default KEXEC_CORE
20361fff234dSArd Biesheuvel	help
20371fff234dSArd Biesheuvel	  Export EFI runtime memory regions to /sys/firmware/efi/runtime-map.
20381fff234dSArd Biesheuvel	  That memory map is required by the 2nd kernel to set up EFI virtual
20391fff234dSArd Biesheuvel	  mappings after kexec, but can also be used for debugging purposes.
20401fff234dSArd Biesheuvel
20411fff234dSArd Biesheuvel	  See also Documentation/ABI/testing/sysfs-firmware-efi-runtime-map.
20421fff234dSArd Biesheuvel
20438636a1f9SMasahiro Yamadasource "kernel/Kconfig.hz"
2044506f1d07SSam Ravnborg
2045506f1d07SSam Ravnborgconfig KEXEC
2046506f1d07SSam Ravnborg	bool "kexec system call"
20472965faa5SDave Young	select KEXEC_CORE
2048a7f7f624SMasahiro Yamada	help
2049506f1d07SSam Ravnborg	  kexec is a system call that implements the ability to shutdown your
2050506f1d07SSam Ravnborg	  current kernel, and to start another kernel.  It is like a reboot
2051506f1d07SSam Ravnborg	  but it is independent of the system firmware.   And like a reboot
2052506f1d07SSam Ravnborg	  you can start any kernel with it, not just Linux.
2053506f1d07SSam Ravnborg
2054506f1d07SSam Ravnborg	  The name comes from the similarity to the exec system call.
2055506f1d07SSam Ravnborg
2056506f1d07SSam Ravnborg	  It is an ongoing process to be certain the hardware in a machine
2057506f1d07SSam Ravnborg	  is properly shutdown, so do not be surprised if this code does not
2058bf220695SGeert Uytterhoeven	  initially work for you.  As of this writing the exact hardware
2059bf220695SGeert Uytterhoeven	  interface is strongly in flux, so no good recommendation can be
2060bf220695SGeert Uytterhoeven	  made.
2061506f1d07SSam Ravnborg
206274ca317cSVivek Goyalconfig KEXEC_FILE
206374ca317cSVivek Goyal	bool "kexec file based system call"
20642965faa5SDave Young	select KEXEC_CORE
2065b69a2afdSJonathan McDowell	select HAVE_IMA_KEXEC if IMA
206674ca317cSVivek Goyal	depends on X86_64
206774ca317cSVivek Goyal	depends on CRYPTO=y
206874ca317cSVivek Goyal	depends on CRYPTO_SHA256=y
2069a7f7f624SMasahiro Yamada	help
207074ca317cSVivek Goyal	  This is new version of kexec system call. This system call is
207174ca317cSVivek Goyal	  file based and takes file descriptors as system call argument
207274ca317cSVivek Goyal	  for kernel and initramfs as opposed to list of segments as
207374ca317cSVivek Goyal	  accepted by previous system call.
207474ca317cSVivek Goyal
2075b799a09fSAKASHI Takahiroconfig ARCH_HAS_KEXEC_PURGATORY
2076b799a09fSAKASHI Takahiro	def_bool KEXEC_FILE
2077b799a09fSAKASHI Takahiro
207899d5cadfSJiri Bohacconfig KEXEC_SIG
20798e7d8381SVivek Goyal	bool "Verify kernel signature during kexec_file_load() syscall"
208074ca317cSVivek Goyal	depends on KEXEC_FILE
2081a7f7f624SMasahiro Yamada	help
208299d5cadfSJiri Bohac
208399d5cadfSJiri Bohac	  This option makes the kexec_file_load() syscall check for a valid
208499d5cadfSJiri Bohac	  signature of the kernel image.  The image can still be loaded without
208599d5cadfSJiri Bohac	  a valid signature unless you also enable KEXEC_SIG_FORCE, though if
208699d5cadfSJiri Bohac	  there's a signature that we can check, then it must be valid.
208799d5cadfSJiri Bohac
208899d5cadfSJiri Bohac	  In addition to this option, you need to enable signature
208999d5cadfSJiri Bohac	  verification for the corresponding kernel image type being
209099d5cadfSJiri Bohac	  loaded in order for this to work.
209199d5cadfSJiri Bohac
209299d5cadfSJiri Bohacconfig KEXEC_SIG_FORCE
209399d5cadfSJiri Bohac	bool "Require a valid signature in kexec_file_load() syscall"
209499d5cadfSJiri Bohac	depends on KEXEC_SIG
2095a7f7f624SMasahiro Yamada	help
20968e7d8381SVivek Goyal	  This option makes kernel signature verification mandatory for
2097d8eb8940SBorislav Petkov	  the kexec_file_load() syscall.
20988e7d8381SVivek Goyal
20998e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG
21008e7d8381SVivek Goyal	bool "Enable bzImage signature verification support"
210199d5cadfSJiri Bohac	depends on KEXEC_SIG
21028e7d8381SVivek Goyal	depends on SIGNED_PE_FILE_VERIFICATION
21038e7d8381SVivek Goyal	select SYSTEM_TRUSTED_KEYRING
2104a7f7f624SMasahiro Yamada	help
21058e7d8381SVivek Goyal	  Enable bzImage signature verification support.
21068e7d8381SVivek Goyal
2107506f1d07SSam Ravnborgconfig CRASH_DUMP
210804b69447SPavel Machek	bool "kernel crash dumps"
2109506f1d07SSam Ravnborg	depends on X86_64 || (X86_32 && HIGHMEM)
2110a7f7f624SMasahiro Yamada	help
2111506f1d07SSam Ravnborg	  Generate crash dump after being started by kexec.
2112506f1d07SSam Ravnborg	  This should be normally only set in special crash dump kernels
2113506f1d07SSam Ravnborg	  which are loaded in the main kernel with kexec-tools into
2114506f1d07SSam Ravnborg	  a specially reserved region and then later executed after
2115506f1d07SSam Ravnborg	  a crash by kdump/kexec. The crash dump kernel must be compiled
2116506f1d07SSam Ravnborg	  to a memory address not used by the main kernel or BIOS using
2117506f1d07SSam Ravnborg	  PHYSICAL_START, or it must be built as a relocatable image
2118506f1d07SSam Ravnborg	  (CONFIG_RELOCATABLE=y).
2119330d4810SMauro Carvalho Chehab	  For more details see Documentation/admin-guide/kdump/kdump.rst
2120506f1d07SSam Ravnborg
21213ab83521SHuang Yingconfig KEXEC_JUMP
21226ea30386SKees Cook	bool "kexec jump"
2123fee7b0d8SHuang Ying	depends on KEXEC && HIBERNATION
2124a7f7f624SMasahiro Yamada	help
212589081d17SHuang Ying	  Jump between original kernel and kexeced kernel and invoke
212689081d17SHuang Ying	  code in physical address mode via KEXEC
21273ab83521SHuang Ying
2128506f1d07SSam Ravnborgconfig PHYSICAL_START
21296a108a14SDavid Rientjes	hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
2130ceefccc9SH. Peter Anvin	default "0x1000000"
2131a7f7f624SMasahiro Yamada	help
2132506f1d07SSam Ravnborg	  This gives the physical address where the kernel is loaded.
2133506f1d07SSam Ravnborg
2134506f1d07SSam Ravnborg	  If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2135506f1d07SSam Ravnborg	  bzImage will decompress itself to above physical address and
2136506f1d07SSam Ravnborg	  run from there. Otherwise, bzImage will run from the address where
2137506f1d07SSam Ravnborg	  it has been loaded by the boot loader and will ignore above physical
2138506f1d07SSam Ravnborg	  address.
2139506f1d07SSam Ravnborg
2140506f1d07SSam Ravnborg	  In normal kdump cases one does not have to set/change this option
2141506f1d07SSam Ravnborg	  as now bzImage can be compiled as a completely relocatable image
2142506f1d07SSam Ravnborg	  (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2143506f1d07SSam Ravnborg	  address. This option is mainly useful for the folks who don't want
2144506f1d07SSam Ravnborg	  to use a bzImage for capturing the crash dump and want to use a
2145506f1d07SSam Ravnborg	  vmlinux instead. vmlinux is not relocatable hence a kernel needs
2146506f1d07SSam Ravnborg	  to be specifically compiled to run from a specific memory area
2147506f1d07SSam Ravnborg	  (normally a reserved region) and this option comes handy.
2148506f1d07SSam Ravnborg
2149ceefccc9SH. Peter Anvin	  So if you are using bzImage for capturing the crash dump,
2150ceefccc9SH. Peter Anvin	  leave the value here unchanged to 0x1000000 and set
2151ceefccc9SH. Peter Anvin	  CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
2152ceefccc9SH. Peter Anvin	  for capturing the crash dump change this value to start of
2153ceefccc9SH. Peter Anvin	  the reserved region.  In other words, it can be set based on
2154ceefccc9SH. Peter Anvin	  the "X" value as specified in the "crashkernel=YM@XM"
2155ceefccc9SH. Peter Anvin	  command line boot parameter passed to the panic-ed
2156330d4810SMauro Carvalho Chehab	  kernel. Please take a look at Documentation/admin-guide/kdump/kdump.rst
2157ceefccc9SH. Peter Anvin	  for more details about crash dumps.
2158506f1d07SSam Ravnborg
2159506f1d07SSam Ravnborg	  Usage of bzImage for capturing the crash dump is recommended as
2160506f1d07SSam Ravnborg	  one does not have to build two kernels. Same kernel can be used
2161506f1d07SSam Ravnborg	  as production kernel and capture kernel. Above option should have
2162506f1d07SSam Ravnborg	  gone away after relocatable bzImage support is introduced. But it
2163506f1d07SSam Ravnborg	  is present because there are users out there who continue to use
2164506f1d07SSam Ravnborg	  vmlinux for dump capture. This option should go away down the
2165506f1d07SSam Ravnborg	  line.
2166506f1d07SSam Ravnborg
2167506f1d07SSam Ravnborg	  Don't change this unless you know what you are doing.
2168506f1d07SSam Ravnborg
2169506f1d07SSam Ravnborgconfig RELOCATABLE
217026717808SH. Peter Anvin	bool "Build a relocatable kernel"
217126717808SH. Peter Anvin	default y
2172a7f7f624SMasahiro Yamada	help
2173506f1d07SSam Ravnborg	  This builds a kernel image that retains relocation information
2174506f1d07SSam Ravnborg	  so it can be loaded someplace besides the default 1MB.
2175506f1d07SSam Ravnborg	  The relocations tend to make the kernel binary about 10% larger,
2176506f1d07SSam Ravnborg	  but are discarded at runtime.
2177506f1d07SSam Ravnborg
2178506f1d07SSam Ravnborg	  One use is for the kexec on panic case where the recovery kernel
2179506f1d07SSam Ravnborg	  must live at a different physical address than the primary
2180506f1d07SSam Ravnborg	  kernel.
2181506f1d07SSam Ravnborg
2182506f1d07SSam Ravnborg	  Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2183506f1d07SSam Ravnborg	  it has been loaded at and the compile time physical address
21848ab3820fSKees Cook	  (CONFIG_PHYSICAL_START) is used as the minimum location.
2185506f1d07SSam Ravnborg
21868ab3820fSKees Cookconfig RANDOMIZE_BASE
2187e8581e3dSBaoquan He	bool "Randomize the address of the kernel image (KASLR)"
21888ab3820fSKees Cook	depends on RELOCATABLE
21896807c846SIngo Molnar	default y
2190a7f7f624SMasahiro Yamada	help
2191e8581e3dSBaoquan He	  In support of Kernel Address Space Layout Randomization (KASLR),
2192e8581e3dSBaoquan He	  this randomizes the physical address at which the kernel image
2193e8581e3dSBaoquan He	  is decompressed and the virtual address where the kernel
2194e8581e3dSBaoquan He	  image is mapped, as a security feature that deters exploit
2195e8581e3dSBaoquan He	  attempts relying on knowledge of the location of kernel
2196e8581e3dSBaoquan He	  code internals.
2197e8581e3dSBaoquan He
2198ed9f007eSKees Cook	  On 64-bit, the kernel physical and virtual addresses are
2199ed9f007eSKees Cook	  randomized separately. The physical address will be anywhere
2200ed9f007eSKees Cook	  between 16MB and the top of physical memory (up to 64TB). The
2201ed9f007eSKees Cook	  virtual address will be randomized from 16MB up to 1GB (9 bits
2202ed9f007eSKees Cook	  of entropy). Note that this also reduces the memory space
2203ed9f007eSKees Cook	  available to kernel modules from 1.5GB to 1GB.
2204ed9f007eSKees Cook
2205ed9f007eSKees Cook	  On 32-bit, the kernel physical and virtual addresses are
2206ed9f007eSKees Cook	  randomized together. They will be randomized from 16MB up to
2207ed9f007eSKees Cook	  512MB (8 bits of entropy).
22088ab3820fSKees Cook
2209a653f356SKees Cook	  Entropy is generated using the RDRAND instruction if it is
2210e8581e3dSBaoquan He	  supported. If RDTSC is supported, its value is mixed into
2211e8581e3dSBaoquan He	  the entropy pool as well. If neither RDRAND nor RDTSC are
2212ed9f007eSKees Cook	  supported, then entropy is read from the i8254 timer. The
2213ed9f007eSKees Cook	  usable entropy is limited by the kernel being built using
2214ed9f007eSKees Cook	  2GB addressing, and that PHYSICAL_ALIGN must be at a
2215ed9f007eSKees Cook	  minimum of 2MB. As a result, only 10 bits of entropy are
2216ed9f007eSKees Cook	  theoretically possible, but the implementations are further
2217ed9f007eSKees Cook	  limited due to memory layouts.
2218e8581e3dSBaoquan He
22196807c846SIngo Molnar	  If unsure, say Y.
2220da2b6fb9SKees Cook
22218ab3820fSKees Cook# Relocation on x86 needs some additional build support
2222845adf72SH. Peter Anvinconfig X86_NEED_RELOCS
2223845adf72SH. Peter Anvin	def_bool y
22248ab3820fSKees Cook	depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
2225845adf72SH. Peter Anvin
2226506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN
2227a0215061SKees Cook	hex "Alignment value to which kernel should be aligned"
22288ab3820fSKees Cook	default "0x200000"
2229a0215061SKees Cook	range 0x2000 0x1000000 if X86_32
2230a0215061SKees Cook	range 0x200000 0x1000000 if X86_64
2231a7f7f624SMasahiro Yamada	help
2232506f1d07SSam Ravnborg	  This value puts the alignment restrictions on physical address
2233506f1d07SSam Ravnborg	  where kernel is loaded and run from. Kernel is compiled for an
2234506f1d07SSam Ravnborg	  address which meets above alignment restriction.
2235506f1d07SSam Ravnborg
2236506f1d07SSam Ravnborg	  If bootloader loads the kernel at a non-aligned address and
2237506f1d07SSam Ravnborg	  CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2238506f1d07SSam Ravnborg	  address aligned to above value and run from there.
2239506f1d07SSam Ravnborg
2240506f1d07SSam Ravnborg	  If bootloader loads the kernel at a non-aligned address and
2241506f1d07SSam Ravnborg	  CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2242506f1d07SSam Ravnborg	  load address and decompress itself to the address it has been
2243506f1d07SSam Ravnborg	  compiled for and run from there. The address for which kernel is
2244506f1d07SSam Ravnborg	  compiled already meets above alignment restrictions. Hence the
2245506f1d07SSam Ravnborg	  end result is that kernel runs from a physical address meeting
2246506f1d07SSam Ravnborg	  above alignment restrictions.
2247506f1d07SSam Ravnborg
2248a0215061SKees Cook	  On 32-bit this value must be a multiple of 0x2000. On 64-bit
2249a0215061SKees Cook	  this value must be a multiple of 0x200000.
2250a0215061SKees Cook
2251506f1d07SSam Ravnborg	  Don't change this unless you know what you are doing.
2252506f1d07SSam Ravnborg
2253eedb92abSKirill A. Shutemovconfig DYNAMIC_MEMORY_LAYOUT
2254eedb92abSKirill A. Shutemov	bool
2255a7f7f624SMasahiro Yamada	help
2256eedb92abSKirill A. Shutemov	  This option makes base addresses of vmalloc and vmemmap as well as
2257eedb92abSKirill A. Shutemov	  __PAGE_OFFSET movable during boot.
2258eedb92abSKirill A. Shutemov
22590483e1faSThomas Garnierconfig RANDOMIZE_MEMORY
22600483e1faSThomas Garnier	bool "Randomize the kernel memory sections"
22610483e1faSThomas Garnier	depends on X86_64
22620483e1faSThomas Garnier	depends on RANDOMIZE_BASE
2263eedb92abSKirill A. Shutemov	select DYNAMIC_MEMORY_LAYOUT
22640483e1faSThomas Garnier	default RANDOMIZE_BASE
2265a7f7f624SMasahiro Yamada	help
22660483e1faSThomas Garnier	  Randomizes the base virtual address of kernel memory sections
22670483e1faSThomas Garnier	  (physical memory mapping, vmalloc & vmemmap). This security feature
22680483e1faSThomas Garnier	  makes exploits relying on predictable memory locations less reliable.
22690483e1faSThomas Garnier
22700483e1faSThomas Garnier	  The order of allocations remains unchanged. Entropy is generated in
22710483e1faSThomas Garnier	  the same way as RANDOMIZE_BASE. Current implementation in the optimal
22720483e1faSThomas Garnier	  configuration have in average 30,000 different possible virtual
22730483e1faSThomas Garnier	  addresses for each memory section.
22740483e1faSThomas Garnier
22756807c846SIngo Molnar	  If unsure, say Y.
22760483e1faSThomas Garnier
227790397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING
227890397a41SThomas Garnier	hex "Physical memory mapping padding" if EXPERT
227990397a41SThomas Garnier	depends on RANDOMIZE_MEMORY
228090397a41SThomas Garnier	default "0xa" if MEMORY_HOTPLUG
228190397a41SThomas Garnier	default "0x0"
228290397a41SThomas Garnier	range 0x1 0x40 if MEMORY_HOTPLUG
228390397a41SThomas Garnier	range 0x0 0x40
2284a7f7f624SMasahiro Yamada	help
228590397a41SThomas Garnier	  Define the padding in terabytes added to the existing physical
228690397a41SThomas Garnier	  memory size during kernel memory randomization. It is useful
228790397a41SThomas Garnier	  for memory hotplug support but reduces the entropy available for
228890397a41SThomas Garnier	  address randomization.
228990397a41SThomas Garnier
229090397a41SThomas Garnier	  If unsure, leave at the default value.
229190397a41SThomas Garnier
22926449dcb0SKirill A. Shutemovconfig ADDRESS_MASKING
22936449dcb0SKirill A. Shutemov	bool "Linear Address Masking support"
22946449dcb0SKirill A. Shutemov	depends on X86_64
22956449dcb0SKirill A. Shutemov	help
22966449dcb0SKirill A. Shutemov	  Linear Address Masking (LAM) modifies the checking that is applied
22976449dcb0SKirill A. Shutemov	  to 64-bit linear addresses, allowing software to use of the
22986449dcb0SKirill A. Shutemov	  untranslated address bits for metadata.
22996449dcb0SKirill A. Shutemov
23006449dcb0SKirill A. Shutemov	  The capability can be used for efficient address sanitizers (ASAN)
23016449dcb0SKirill A. Shutemov	  implementation and for optimizations in JITs.
23026449dcb0SKirill A. Shutemov
2303506f1d07SSam Ravnborgconfig HOTPLUG_CPU
2304bebd024eSThomas Gleixner	def_bool y
230540b31360SStephen Rothwell	depends on SMP
2306506f1d07SSam Ravnborg
2307506f1d07SSam Ravnborgconfig COMPAT_VDSO
2308b0b49f26SAndy Lutomirski	def_bool n
2309b0b49f26SAndy Lutomirski	prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
2310953fee1dSIngo Molnar	depends on COMPAT_32
2311a7f7f624SMasahiro Yamada	help
2312b0b49f26SAndy Lutomirski	  Certain buggy versions of glibc will crash if they are
2313b0b49f26SAndy Lutomirski	  presented with a 32-bit vDSO that is not mapped at the address
2314b0b49f26SAndy Lutomirski	  indicated in its segment table.
2315e84446deSRandy Dunlap
2316b0b49f26SAndy Lutomirski	  The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2317b0b49f26SAndy Lutomirski	  and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2318b0b49f26SAndy Lutomirski	  49ad572a70b8aeb91e57483a11dd1b77e31c4468.  Glibc 2.3.3 is
2319b0b49f26SAndy Lutomirski	  the only released version with the bug, but OpenSUSE 9
2320b0b49f26SAndy Lutomirski	  contains a buggy "glibc 2.3.2".
2321506f1d07SSam Ravnborg
2322b0b49f26SAndy Lutomirski	  The symptom of the bug is that everything crashes on startup, saying:
2323b0b49f26SAndy Lutomirski	  dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2324b0b49f26SAndy Lutomirski
2325b0b49f26SAndy Lutomirski	  Saying Y here changes the default value of the vdso32 boot
2326b0b49f26SAndy Lutomirski	  option from 1 to 0, which turns off the 32-bit vDSO entirely.
2327b0b49f26SAndy Lutomirski	  This works around the glibc bug but hurts performance.
2328b0b49f26SAndy Lutomirski
2329b0b49f26SAndy Lutomirski	  If unsure, say N: if you are compiling your own kernel, you
2330b0b49f26SAndy Lutomirski	  are unlikely to be using a buggy version of glibc.
2331506f1d07SSam Ravnborg
23323dc33bd3SKees Cookchoice
23333dc33bd3SKees Cook	prompt "vsyscall table for legacy applications"
23343dc33bd3SKees Cook	depends on X86_64
2335625b7b7fSAndy Lutomirski	default LEGACY_VSYSCALL_XONLY
23363dc33bd3SKees Cook	help
23373dc33bd3SKees Cook	  Legacy user code that does not know how to find the vDSO expects
23383dc33bd3SKees Cook	  to be able to issue three syscalls by calling fixed addresses in
23393dc33bd3SKees Cook	  kernel space. Since this location is not randomized with ASLR,
23403dc33bd3SKees Cook	  it can be used to assist security vulnerability exploitation.
23413dc33bd3SKees Cook
23423dc33bd3SKees Cook	  This setting can be changed at boot time via the kernel command
2343bf00745eSAndy Lutomirski	  line parameter vsyscall=[emulate|xonly|none].  Emulate mode
2344bf00745eSAndy Lutomirski	  is deprecated and can only be enabled using the kernel command
2345bf00745eSAndy Lutomirski	  line.
23463dc33bd3SKees Cook
23473dc33bd3SKees Cook	  On a system with recent enough glibc (2.14 or newer) and no
23483dc33bd3SKees Cook	  static binaries, you can say None without a performance penalty
23493dc33bd3SKees Cook	  to improve security.
23503dc33bd3SKees Cook
2351bd49e16eSAndy Lutomirski	  If unsure, select "Emulate execution only".
23523dc33bd3SKees Cook
2353bd49e16eSAndy Lutomirski	config LEGACY_VSYSCALL_XONLY
2354bd49e16eSAndy Lutomirski		bool "Emulate execution only"
2355bd49e16eSAndy Lutomirski		help
2356bd49e16eSAndy Lutomirski		  The kernel traps and emulates calls into the fixed vsyscall
2357bd49e16eSAndy Lutomirski		  address mapping and does not allow reads.  This
2358bd49e16eSAndy Lutomirski		  configuration is recommended when userspace might use the
2359bd49e16eSAndy Lutomirski		  legacy vsyscall area but support for legacy binary
2360bd49e16eSAndy Lutomirski		  instrumentation of legacy code is not needed.  It mitigates
2361bd49e16eSAndy Lutomirski		  certain uses of the vsyscall area as an ASLR-bypassing
2362bd49e16eSAndy Lutomirski		  buffer.
23633dc33bd3SKees Cook
23643dc33bd3SKees Cook	config LEGACY_VSYSCALL_NONE
23653dc33bd3SKees Cook		bool "None"
23663dc33bd3SKees Cook		help
23673dc33bd3SKees Cook		  There will be no vsyscall mapping at all. This will
23683dc33bd3SKees Cook		  eliminate any risk of ASLR bypass due to the vsyscall
23693dc33bd3SKees Cook		  fixed address mapping. Attempts to use the vsyscalls
23703dc33bd3SKees Cook		  will be reported to dmesg, so that either old or
23713dc33bd3SKees Cook		  malicious userspace programs can be identified.
23723dc33bd3SKees Cook
23733dc33bd3SKees Cookendchoice
23743dc33bd3SKees Cook
2375516cbf37STim Birdconfig CMDLINE_BOOL
2376516cbf37STim Bird	bool "Built-in kernel command line"
2377a7f7f624SMasahiro Yamada	help
2378516cbf37STim Bird	  Allow for specifying boot arguments to the kernel at
2379516cbf37STim Bird	  build time.  On some systems (e.g. embedded ones), it is
2380516cbf37STim Bird	  necessary or convenient to provide some or all of the
2381516cbf37STim Bird	  kernel boot arguments with the kernel itself (that is,
2382516cbf37STim Bird	  to not rely on the boot loader to provide them.)
2383516cbf37STim Bird
2384516cbf37STim Bird	  To compile command line arguments into the kernel,
2385516cbf37STim Bird	  set this option to 'Y', then fill in the
238669711ca1SSébastien Hinderer	  boot arguments in CONFIG_CMDLINE.
2387516cbf37STim Bird
2388516cbf37STim Bird	  Systems with fully functional boot loaders (i.e. non-embedded)
2389516cbf37STim Bird	  should leave this option set to 'N'.
2390516cbf37STim Bird
2391516cbf37STim Birdconfig CMDLINE
2392516cbf37STim Bird	string "Built-in kernel command string"
2393516cbf37STim Bird	depends on CMDLINE_BOOL
2394516cbf37STim Bird	default ""
2395a7f7f624SMasahiro Yamada	help
2396516cbf37STim Bird	  Enter arguments here that should be compiled into the kernel
2397516cbf37STim Bird	  image and used at boot time.  If the boot loader provides a
2398516cbf37STim Bird	  command line at boot time, it is appended to this string to
2399516cbf37STim Bird	  form the full kernel command line, when the system boots.
2400516cbf37STim Bird
2401516cbf37STim Bird	  However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2402516cbf37STim Bird	  change this behavior.
2403516cbf37STim Bird
2404516cbf37STim Bird	  In most cases, the command line (whether built-in or provided
2405516cbf37STim Bird	  by the boot loader) should specify the device for the root
2406516cbf37STim Bird	  file system.
2407516cbf37STim Bird
2408516cbf37STim Birdconfig CMDLINE_OVERRIDE
2409516cbf37STim Bird	bool "Built-in command line overrides boot loader arguments"
2410645e6466SAnders Roxell	depends on CMDLINE_BOOL && CMDLINE != ""
2411a7f7f624SMasahiro Yamada	help
2412516cbf37STim Bird	  Set this option to 'Y' to have the kernel ignore the boot loader
2413516cbf37STim Bird	  command line, and use ONLY the built-in command line.
2414516cbf37STim Bird
2415516cbf37STim Bird	  This is used to work around broken boot loaders.  This should
2416516cbf37STim Bird	  be set to 'N' under normal conditions.
2417516cbf37STim Bird
2418a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL
2419a5b9e5a2SAndy Lutomirski	bool "Enable the LDT (local descriptor table)" if EXPERT
2420a5b9e5a2SAndy Lutomirski	default y
2421a7f7f624SMasahiro Yamada	help
2422a5b9e5a2SAndy Lutomirski	  Linux can allow user programs to install a per-process x86
2423a5b9e5a2SAndy Lutomirski	  Local Descriptor Table (LDT) using the modify_ldt(2) system
2424a5b9e5a2SAndy Lutomirski	  call.  This is required to run 16-bit or segmented code such as
2425a5b9e5a2SAndy Lutomirski	  DOSEMU or some Wine programs.  It is also used by some very old
2426a5b9e5a2SAndy Lutomirski	  threading libraries.
2427a5b9e5a2SAndy Lutomirski
2428a5b9e5a2SAndy Lutomirski	  Enabling this feature adds a small amount of overhead to
2429a5b9e5a2SAndy Lutomirski	  context switches and increases the low-level kernel attack
2430a5b9e5a2SAndy Lutomirski	  surface.  Disabling it removes the modify_ldt(2) system call.
2431a5b9e5a2SAndy Lutomirski
2432a5b9e5a2SAndy Lutomirski	  Saying 'N' here may make sense for embedded or server kernels.
2433a5b9e5a2SAndy Lutomirski
24343aac3ebeSThomas Gleixnerconfig STRICT_SIGALTSTACK_SIZE
24353aac3ebeSThomas Gleixner	bool "Enforce strict size checking for sigaltstack"
24363aac3ebeSThomas Gleixner	depends on DYNAMIC_SIGFRAME
24373aac3ebeSThomas Gleixner	help
24383aac3ebeSThomas Gleixner	  For historical reasons MINSIGSTKSZ is a constant which became
24393aac3ebeSThomas Gleixner	  already too small with AVX512 support. Add a mechanism to
24403aac3ebeSThomas Gleixner	  enforce strict checking of the sigaltstack size against the
24413aac3ebeSThomas Gleixner	  real size of the FPU frame. This option enables the check
24423aac3ebeSThomas Gleixner	  by default. It can also be controlled via the kernel command
24433aac3ebeSThomas Gleixner	  line option 'strict_sas_size' independent of this config
24443aac3ebeSThomas Gleixner	  switch. Enabling it might break existing applications which
24453aac3ebeSThomas Gleixner	  allocate a too small sigaltstack but 'work' because they
24463aac3ebeSThomas Gleixner	  never get a signal delivered.
24473aac3ebeSThomas Gleixner
24483aac3ebeSThomas Gleixner	  Say 'N' unless you want to really enforce this check.
24493aac3ebeSThomas Gleixner
2450b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig"
2451b700e7f0SSeth Jennings
2452506f1d07SSam Ravnborgendmenu
2453506f1d07SSam Ravnborg
2454f43b9876SPeter Zijlstraconfig CC_HAS_SLS
2455f43b9876SPeter Zijlstra	def_bool $(cc-option,-mharden-sls=all)
2456f43b9876SPeter Zijlstra
2457f43b9876SPeter Zijlstraconfig CC_HAS_RETURN_THUNK
2458f43b9876SPeter Zijlstra	def_bool $(cc-option,-mfunction-return=thunk-extern)
2459f43b9876SPeter Zijlstra
2460bea75b33SThomas Gleixnerconfig CC_HAS_ENTRY_PADDING
2461bea75b33SThomas Gleixner	def_bool $(cc-option,-fpatchable-function-entry=16,16)
2462bea75b33SThomas Gleixner
2463bea75b33SThomas Gleixnerconfig FUNCTION_PADDING_CFI
2464bea75b33SThomas Gleixner	int
2465bea75b33SThomas Gleixner	default 59 if FUNCTION_ALIGNMENT_64B
2466bea75b33SThomas Gleixner	default 27 if FUNCTION_ALIGNMENT_32B
2467bea75b33SThomas Gleixner	default 11 if FUNCTION_ALIGNMENT_16B
2468bea75b33SThomas Gleixner	default  3 if FUNCTION_ALIGNMENT_8B
2469bea75b33SThomas Gleixner	default  0
2470bea75b33SThomas Gleixner
2471bea75b33SThomas Gleixner# Basically: FUNCTION_ALIGNMENT - 5*CFI_CLANG
2472bea75b33SThomas Gleixner# except Kconfig can't do arithmetic :/
2473bea75b33SThomas Gleixnerconfig FUNCTION_PADDING_BYTES
2474bea75b33SThomas Gleixner	int
2475bea75b33SThomas Gleixner	default FUNCTION_PADDING_CFI if CFI_CLANG
2476bea75b33SThomas Gleixner	default FUNCTION_ALIGNMENT
2477bea75b33SThomas Gleixner
2478931ab636SPeter Zijlstraconfig CALL_PADDING
2479931ab636SPeter Zijlstra	def_bool n
2480931ab636SPeter Zijlstra	depends on CC_HAS_ENTRY_PADDING && OBJTOOL
2481931ab636SPeter Zijlstra	select FUNCTION_ALIGNMENT_16B
2482931ab636SPeter Zijlstra
2483931ab636SPeter Zijlstraconfig FINEIBT
2484931ab636SPeter Zijlstra	def_bool y
2485931ab636SPeter Zijlstra	depends on X86_KERNEL_IBT && CFI_CLANG && RETPOLINE
2486931ab636SPeter Zijlstra	select CALL_PADDING
2487931ab636SPeter Zijlstra
24888f7c0d8bSThomas Gleixnerconfig HAVE_CALL_THUNKS
24898f7c0d8bSThomas Gleixner	def_bool y
2490bea75b33SThomas Gleixner	depends on CC_HAS_ENTRY_PADDING && RETHUNK && OBJTOOL
24918f7c0d8bSThomas Gleixner
24928f7c0d8bSThomas Gleixnerconfig CALL_THUNKS
24938f7c0d8bSThomas Gleixner	def_bool n
2494931ab636SPeter Zijlstra	select CALL_PADDING
24958f7c0d8bSThomas Gleixner
2496b341b20dSPeter Zijlstraconfig PREFIX_SYMBOLS
2497b341b20dSPeter Zijlstra	def_bool y
2498931ab636SPeter Zijlstra	depends on CALL_PADDING && !CFI_CLANG
2499b341b20dSPeter Zijlstra
2500f43b9876SPeter Zijlstramenuconfig SPECULATION_MITIGATIONS
2501f43b9876SPeter Zijlstra	bool "Mitigations for speculative execution vulnerabilities"
2502f43b9876SPeter Zijlstra	default y
2503f43b9876SPeter Zijlstra	help
2504f43b9876SPeter Zijlstra	  Say Y here to enable options which enable mitigations for
2505f43b9876SPeter Zijlstra	  speculative execution hardware vulnerabilities.
2506f43b9876SPeter Zijlstra
2507f43b9876SPeter Zijlstra	  If you say N, all mitigations will be disabled. You really
2508f43b9876SPeter Zijlstra	  should know what you are doing to say so.
2509f43b9876SPeter Zijlstra
2510f43b9876SPeter Zijlstraif SPECULATION_MITIGATIONS
2511f43b9876SPeter Zijlstra
2512f43b9876SPeter Zijlstraconfig PAGE_TABLE_ISOLATION
2513f43b9876SPeter Zijlstra	bool "Remove the kernel mapping in user mode"
2514f43b9876SPeter Zijlstra	default y
2515f43b9876SPeter Zijlstra	depends on (X86_64 || X86_PAE)
2516f43b9876SPeter Zijlstra	help
2517f43b9876SPeter Zijlstra	  This feature reduces the number of hardware side channels by
2518f43b9876SPeter Zijlstra	  ensuring that the majority of kernel addresses are not mapped
2519f43b9876SPeter Zijlstra	  into userspace.
2520f43b9876SPeter Zijlstra
2521ff61f079SJonathan Corbet	  See Documentation/arch/x86/pti.rst for more details.
2522f43b9876SPeter Zijlstra
2523f43b9876SPeter Zijlstraconfig RETPOLINE
2524f43b9876SPeter Zijlstra	bool "Avoid speculative indirect branches in kernel"
2525f43b9876SPeter Zijlstra	select OBJTOOL if HAVE_OBJTOOL
2526f43b9876SPeter Zijlstra	default y
2527f43b9876SPeter Zijlstra	help
2528f43b9876SPeter Zijlstra	  Compile kernel with the retpoline compiler options to guard against
2529f43b9876SPeter Zijlstra	  kernel-to-user data leaks by avoiding speculative indirect
2530f43b9876SPeter Zijlstra	  branches. Requires a compiler with -mindirect-branch=thunk-extern
2531f43b9876SPeter Zijlstra	  support for full protection. The kernel may run slower.
2532f43b9876SPeter Zijlstra
2533f43b9876SPeter Zijlstraconfig RETHUNK
2534f43b9876SPeter Zijlstra	bool "Enable return-thunks"
2535f43b9876SPeter Zijlstra	depends on RETPOLINE && CC_HAS_RETURN_THUNK
2536f43b9876SPeter Zijlstra	select OBJTOOL if HAVE_OBJTOOL
2537b648ab48SBen Hutchings	default y if X86_64
2538f43b9876SPeter Zijlstra	help
2539f43b9876SPeter Zijlstra	  Compile the kernel with the return-thunks compiler option to guard
2540f43b9876SPeter Zijlstra	  against kernel-to-user data leaks by avoiding return speculation.
2541f43b9876SPeter Zijlstra	  Requires a compiler with -mfunction-return=thunk-extern
2542f43b9876SPeter Zijlstra	  support for full protection. The kernel may run slower.
2543f43b9876SPeter Zijlstra
2544f43b9876SPeter Zijlstraconfig CPU_UNRET_ENTRY
2545f43b9876SPeter Zijlstra	bool "Enable UNRET on kernel entry"
2546b648ab48SBen Hutchings	depends on CPU_SUP_AMD && RETHUNK && X86_64
2547f43b9876SPeter Zijlstra	default y
2548f43b9876SPeter Zijlstra	help
2549f43b9876SPeter Zijlstra	  Compile the kernel with support for the retbleed=unret mitigation.
2550f43b9876SPeter Zijlstra
255180e4c1cdSThomas Gleixnerconfig CALL_DEPTH_TRACKING
255280e4c1cdSThomas Gleixner	bool "Mitigate RSB underflow with call depth tracking"
255380e4c1cdSThomas Gleixner	depends on CPU_SUP_INTEL && HAVE_CALL_THUNKS
255480e4c1cdSThomas Gleixner	select HAVE_DYNAMIC_FTRACE_NO_PATCHABLE
255580e4c1cdSThomas Gleixner	select CALL_THUNKS
255680e4c1cdSThomas Gleixner	default y
255780e4c1cdSThomas Gleixner	help
255880e4c1cdSThomas Gleixner	  Compile the kernel with call depth tracking to mitigate the Intel
255980e4c1cdSThomas Gleixner	  SKL Return-Speculation-Buffer (RSB) underflow issue. The
256080e4c1cdSThomas Gleixner	  mitigation is off by default and needs to be enabled on the
256180e4c1cdSThomas Gleixner	  kernel command line via the retbleed=stuff option. For
256280e4c1cdSThomas Gleixner	  non-affected systems the overhead of this option is marginal as
256380e4c1cdSThomas Gleixner	  the call depth tracking is using run-time generated call thunks
256480e4c1cdSThomas Gleixner	  in a compiler generated padding area and call patching. This
256580e4c1cdSThomas Gleixner	  increases text size by ~5%. For non affected systems this space
256680e4c1cdSThomas Gleixner	  is unused. On affected SKL systems this results in a significant
256780e4c1cdSThomas Gleixner	  performance gain over the IBRS mitigation.
256880e4c1cdSThomas Gleixner
2569e81dc127SThomas Gleixnerconfig CALL_THUNKS_DEBUG
2570e81dc127SThomas Gleixner	bool "Enable call thunks and call depth tracking debugging"
2571e81dc127SThomas Gleixner	depends on CALL_DEPTH_TRACKING
2572e81dc127SThomas Gleixner	select FUNCTION_ALIGNMENT_32B
2573e81dc127SThomas Gleixner	default n
2574e81dc127SThomas Gleixner	help
2575e81dc127SThomas Gleixner	  Enable call/ret counters for imbalance detection and build in
2576e81dc127SThomas Gleixner	  a noisy dmesg about callthunks generation and call patching for
2577e81dc127SThomas Gleixner	  trouble shooting. The debug prints need to be enabled on the
2578e81dc127SThomas Gleixner	  kernel command line with 'debug-callthunks'.
257954628de6SRandy Dunlap	  Only enable this when you are debugging call thunks as this
258054628de6SRandy Dunlap	  creates a noticeable runtime overhead. If unsure say N.
258180e4c1cdSThomas Gleixner
2582f43b9876SPeter Zijlstraconfig CPU_IBPB_ENTRY
2583f43b9876SPeter Zijlstra	bool "Enable IBPB on kernel entry"
2584b648ab48SBen Hutchings	depends on CPU_SUP_AMD && X86_64
2585f43b9876SPeter Zijlstra	default y
2586f43b9876SPeter Zijlstra	help
2587f43b9876SPeter Zijlstra	  Compile the kernel with support for the retbleed=ibpb mitigation.
2588f43b9876SPeter Zijlstra
2589f43b9876SPeter Zijlstraconfig CPU_IBRS_ENTRY
2590f43b9876SPeter Zijlstra	bool "Enable IBRS on kernel entry"
2591b648ab48SBen Hutchings	depends on CPU_SUP_INTEL && X86_64
2592f43b9876SPeter Zijlstra	default y
2593f43b9876SPeter Zijlstra	help
2594f43b9876SPeter Zijlstra	  Compile the kernel with support for the spectre_v2=ibrs mitigation.
2595f43b9876SPeter Zijlstra	  This mitigates both spectre_v2 and retbleed at great cost to
2596f43b9876SPeter Zijlstra	  performance.
2597f43b9876SPeter Zijlstra
2598f43b9876SPeter Zijlstraconfig SLS
2599f43b9876SPeter Zijlstra	bool "Mitigate Straight-Line-Speculation"
2600f43b9876SPeter Zijlstra	depends on CC_HAS_SLS && X86_64
2601f43b9876SPeter Zijlstra	select OBJTOOL if HAVE_OBJTOOL
2602f43b9876SPeter Zijlstra	default n
2603f43b9876SPeter Zijlstra	help
2604f43b9876SPeter Zijlstra	  Compile the kernel with straight-line-speculation options to guard
2605f43b9876SPeter Zijlstra	  against straight line speculation. The kernel image might be slightly
2606f43b9876SPeter Zijlstra	  larger.
2607f43b9876SPeter Zijlstra
2608f43b9876SPeter Zijlstraendif
2609f43b9876SPeter Zijlstra
26103072e413SMichal Hockoconfig ARCH_HAS_ADD_PAGES
26113072e413SMichal Hocko	def_bool y
26125c11f00bSDavid Hildenbrand	depends on ARCH_ENABLE_MEMORY_HOTPLUG
26133072e413SMichal Hocko
2614da85f865SBjorn Helgaasmenu "Power management and ACPI options"
2615e279b6c1SSam Ravnborg
2616e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER
26173c2362e6SHarvey Harrison	def_bool y
261844556530SZhimin Gu	depends on HIBERNATION
2619e279b6c1SSam Ravnborg
2620e279b6c1SSam Ravnborgsource "kernel/power/Kconfig"
2621e279b6c1SSam Ravnborg
2622e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig"
2623e279b6c1SSam Ravnborg
2624a6b68076SAndi Kleenconfig X86_APM_BOOT
26256fc108a0SJan Beulich	def_bool y
2626282e5aabSPaul Bolle	depends on APM
2627a6b68076SAndi Kleen
2628e279b6c1SSam Ravnborgmenuconfig APM
2629e279b6c1SSam Ravnborg	tristate "APM (Advanced Power Management) BIOS support"
2630efefa6f6SIngo Molnar	depends on X86_32 && PM_SLEEP
2631a7f7f624SMasahiro Yamada	help
2632e279b6c1SSam Ravnborg	  APM is a BIOS specification for saving power using several different
2633e279b6c1SSam Ravnborg	  techniques. This is mostly useful for battery powered laptops with
2634e279b6c1SSam Ravnborg	  APM compliant BIOSes. If you say Y here, the system time will be
2635e279b6c1SSam Ravnborg	  reset after a RESUME operation, the /proc/apm device will provide
2636e279b6c1SSam Ravnborg	  battery status information, and user-space programs will receive
2637e279b6c1SSam Ravnborg	  notification of APM "events" (e.g. battery status change).
2638e279b6c1SSam Ravnborg
2639e279b6c1SSam Ravnborg	  If you select "Y" here, you can disable actual use of the APM
2640e279b6c1SSam Ravnborg	  BIOS by passing the "apm=off" option to the kernel at boot time.
2641e279b6c1SSam Ravnborg
2642e279b6c1SSam Ravnborg	  Note that the APM support is almost completely disabled for
2643e279b6c1SSam Ravnborg	  machines with more than one CPU.
2644e279b6c1SSam Ravnborg
2645e279b6c1SSam Ravnborg	  In order to use APM, you will need supporting software. For location
2646151f4e2bSMauro Carvalho Chehab	  and more information, read <file:Documentation/power/apm-acpi.rst>
26472dc98fd3SMichael Witten	  and the Battery Powered Linux mini-HOWTO, available from
2648e279b6c1SSam Ravnborg	  <http://www.tldp.org/docs.html#howto>.
2649e279b6c1SSam Ravnborg
2650e279b6c1SSam Ravnborg	  This driver does not spin down disk drives (see the hdparm(8)
2651e279b6c1SSam Ravnborg	  manpage ("man 8 hdparm") for that), and it doesn't turn off
2652e279b6c1SSam Ravnborg	  VESA-compliant "green" monitors.
2653e279b6c1SSam Ravnborg
2654e279b6c1SSam Ravnborg	  This driver does not support the TI 4000M TravelMate and the ACER
2655e279b6c1SSam Ravnborg	  486/DX4/75 because they don't have compliant BIOSes. Many "green"
2656e279b6c1SSam Ravnborg	  desktop machines also don't have compliant BIOSes, and this driver
2657e279b6c1SSam Ravnborg	  may cause those machines to panic during the boot phase.
2658e279b6c1SSam Ravnborg
2659e279b6c1SSam Ravnborg	  Generally, if you don't have a battery in your machine, there isn't
2660e279b6c1SSam Ravnborg	  much point in using this driver and you should say N. If you get
2661e279b6c1SSam Ravnborg	  random kernel OOPSes or reboots that don't seem to be related to
2662e279b6c1SSam Ravnborg	  anything, try disabling/enabling this option (or disabling/enabling
2663e279b6c1SSam Ravnborg	  APM in your BIOS).
2664e279b6c1SSam Ravnborg
2665e279b6c1SSam Ravnborg	  Some other things you should try when experiencing seemingly random,
2666e279b6c1SSam Ravnborg	  "weird" problems:
2667e279b6c1SSam Ravnborg
2668e279b6c1SSam Ravnborg	  1) make sure that you have enough swap space and that it is
2669e279b6c1SSam Ravnborg	  enabled.
26707987448fSStephen Kitt	  2) pass the "idle=poll" option to the kernel
2671e279b6c1SSam Ravnborg	  3) switch on floating point emulation in the kernel and pass
2672e279b6c1SSam Ravnborg	  the "no387" option to the kernel
2673e279b6c1SSam Ravnborg	  4) pass the "floppy=nodma" option to the kernel
2674e279b6c1SSam Ravnborg	  5) pass the "mem=4M" option to the kernel (thereby disabling
2675e279b6c1SSam Ravnborg	  all but the first 4 MB of RAM)
2676e279b6c1SSam Ravnborg	  6) make sure that the CPU is not over clocked.
2677e279b6c1SSam Ravnborg	  7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2678e279b6c1SSam Ravnborg	  8) disable the cache from your BIOS settings
2679e279b6c1SSam Ravnborg	  9) install a fan for the video card or exchange video RAM
2680e279b6c1SSam Ravnborg	  10) install a better fan for the CPU
2681e279b6c1SSam Ravnborg	  11) exchange RAM chips
2682e279b6c1SSam Ravnborg	  12) exchange the motherboard.
2683e279b6c1SSam Ravnborg
2684e279b6c1SSam Ravnborg	  To compile this driver as a module, choose M here: the
2685e279b6c1SSam Ravnborg	  module will be called apm.
2686e279b6c1SSam Ravnborg
2687e279b6c1SSam Ravnborgif APM
2688e279b6c1SSam Ravnborg
2689e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND
2690e279b6c1SSam Ravnborg	bool "Ignore USER SUSPEND"
2691a7f7f624SMasahiro Yamada	help
2692e279b6c1SSam Ravnborg	  This option will ignore USER SUSPEND requests. On machines with a
2693e279b6c1SSam Ravnborg	  compliant APM BIOS, you want to say N. However, on the NEC Versa M
2694e279b6c1SSam Ravnborg	  series notebooks, it is necessary to say Y because of a BIOS bug.
2695e279b6c1SSam Ravnborg
2696e279b6c1SSam Ravnborgconfig APM_DO_ENABLE
2697e279b6c1SSam Ravnborg	bool "Enable PM at boot time"
2698a7f7f624SMasahiro Yamada	help
2699e279b6c1SSam Ravnborg	  Enable APM features at boot time. From page 36 of the APM BIOS
2700e279b6c1SSam Ravnborg	  specification: "When disabled, the APM BIOS does not automatically
2701e279b6c1SSam Ravnborg	  power manage devices, enter the Standby State, enter the Suspend
2702e279b6c1SSam Ravnborg	  State, or take power saving steps in response to CPU Idle calls."
2703e279b6c1SSam Ravnborg	  This driver will make CPU Idle calls when Linux is idle (unless this
2704e279b6c1SSam Ravnborg	  feature is turned off -- see "Do CPU IDLE calls", below). This
2705e279b6c1SSam Ravnborg	  should always save battery power, but more complicated APM features
2706e279b6c1SSam Ravnborg	  will be dependent on your BIOS implementation. You may need to turn
2707e279b6c1SSam Ravnborg	  this option off if your computer hangs at boot time when using APM
2708e279b6c1SSam Ravnborg	  support, or if it beeps continuously instead of suspending. Turn
2709e279b6c1SSam Ravnborg	  this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2710e279b6c1SSam Ravnborg	  T400CDT. This is off by default since most machines do fine without
2711e279b6c1SSam Ravnborg	  this feature.
2712e279b6c1SSam Ravnborg
2713e279b6c1SSam Ravnborgconfig APM_CPU_IDLE
2714dd8af076SLen Brown	depends on CPU_IDLE
2715e279b6c1SSam Ravnborg	bool "Make CPU Idle calls when idle"
2716a7f7f624SMasahiro Yamada	help
2717e279b6c1SSam Ravnborg	  Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2718e279b6c1SSam Ravnborg	  On some machines, this can activate improved power savings, such as
2719e279b6c1SSam Ravnborg	  a slowed CPU clock rate, when the machine is idle. These idle calls
2720e279b6c1SSam Ravnborg	  are made after the idle loop has run for some length of time (e.g.,
2721e279b6c1SSam Ravnborg	  333 mS). On some machines, this will cause a hang at boot time or
2722e279b6c1SSam Ravnborg	  whenever the CPU becomes idle. (On machines with more than one CPU,
2723e279b6c1SSam Ravnborg	  this option does nothing.)
2724e279b6c1SSam Ravnborg
2725e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK
2726e279b6c1SSam Ravnborg	bool "Enable console blanking using APM"
2727a7f7f624SMasahiro Yamada	help
2728e279b6c1SSam Ravnborg	  Enable console blanking using the APM. Some laptops can use this to
2729e279b6c1SSam Ravnborg	  turn off the LCD backlight when the screen blanker of the Linux
2730e279b6c1SSam Ravnborg	  virtual console blanks the screen. Note that this is only used by
2731e279b6c1SSam Ravnborg	  the virtual console screen blanker, and won't turn off the backlight
2732e279b6c1SSam Ravnborg	  when using the X Window system. This also doesn't have anything to
2733e279b6c1SSam Ravnborg	  do with your VESA-compliant power-saving monitor. Further, this
2734e279b6c1SSam Ravnborg	  option doesn't work for all laptops -- it might not turn off your
2735e279b6c1SSam Ravnborg	  backlight at all, or it might print a lot of errors to the console,
2736e279b6c1SSam Ravnborg	  especially if you are using gpm.
2737e279b6c1SSam Ravnborg
2738e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS
2739e279b6c1SSam Ravnborg	bool "Allow interrupts during APM BIOS calls"
2740a7f7f624SMasahiro Yamada	help
2741e279b6c1SSam Ravnborg	  Normally we disable external interrupts while we are making calls to
2742e279b6c1SSam Ravnborg	  the APM BIOS as a measure to lessen the effects of a badly behaving
2743e279b6c1SSam Ravnborg	  BIOS implementation.  The BIOS should reenable interrupts if it
2744e279b6c1SSam Ravnborg	  needs to.  Unfortunately, some BIOSes do not -- especially those in
2745e279b6c1SSam Ravnborg	  many of the newer IBM Thinkpads.  If you experience hangs when you
2746e279b6c1SSam Ravnborg	  suspend, try setting this to Y.  Otherwise, say N.
2747e279b6c1SSam Ravnborg
2748e279b6c1SSam Ravnborgendif # APM
2749e279b6c1SSam Ravnborg
2750bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig"
2751e279b6c1SSam Ravnborg
2752e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig"
2753e279b6c1SSam Ravnborg
275427471fdbSAndy Henroidsource "drivers/idle/Kconfig"
275527471fdbSAndy Henroid
2756e279b6c1SSam Ravnborgendmenu
2757e279b6c1SSam Ravnborg
2758e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)"
2759e279b6c1SSam Ravnborg
2760e279b6c1SSam Ravnborgchoice
2761e279b6c1SSam Ravnborg	prompt "PCI access mode"
2762efefa6f6SIngo Molnar	depends on X86_32 && PCI
2763e279b6c1SSam Ravnborg	default PCI_GOANY
2764a7f7f624SMasahiro Yamada	help
2765e279b6c1SSam Ravnborg	  On PCI systems, the BIOS can be used to detect the PCI devices and
2766e279b6c1SSam Ravnborg	  determine their configuration. However, some old PCI motherboards
2767e279b6c1SSam Ravnborg	  have BIOS bugs and may crash if this is done. Also, some embedded
2768e279b6c1SSam Ravnborg	  PCI-based systems don't have any BIOS at all. Linux can also try to
2769e279b6c1SSam Ravnborg	  detect the PCI hardware directly without using the BIOS.
2770e279b6c1SSam Ravnborg
2771e279b6c1SSam Ravnborg	  With this option, you can specify how Linux should detect the
2772e279b6c1SSam Ravnborg	  PCI devices. If you choose "BIOS", the BIOS will be used,
2773e279b6c1SSam Ravnborg	  if you choose "Direct", the BIOS won't be used, and if you
2774e279b6c1SSam Ravnborg	  choose "MMConfig", then PCI Express MMCONFIG will be used.
2775e279b6c1SSam Ravnborg	  If you choose "Any", the kernel will try MMCONFIG, then the
2776e279b6c1SSam Ravnborg	  direct access method and falls back to the BIOS if that doesn't
2777e279b6c1SSam Ravnborg	  work. If unsure, go with the default, which is "Any".
2778e279b6c1SSam Ravnborg
2779e279b6c1SSam Ravnborgconfig PCI_GOBIOS
2780e279b6c1SSam Ravnborg	bool "BIOS"
2781e279b6c1SSam Ravnborg
2782e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG
2783e279b6c1SSam Ravnborg	bool "MMConfig"
2784e279b6c1SSam Ravnborg
2785e279b6c1SSam Ravnborgconfig PCI_GODIRECT
2786e279b6c1SSam Ravnborg	bool "Direct"
2787e279b6c1SSam Ravnborg
27883ef0e1f8SAndres Salomonconfig PCI_GOOLPC
278976fb6570SDaniel Drake	bool "OLPC XO-1"
27903ef0e1f8SAndres Salomon	depends on OLPC
27913ef0e1f8SAndres Salomon
27922bdd1b03SAndres Salomonconfig PCI_GOANY
27932bdd1b03SAndres Salomon	bool "Any"
27942bdd1b03SAndres Salomon
2795e279b6c1SSam Ravnborgendchoice
2796e279b6c1SSam Ravnborg
2797e279b6c1SSam Ravnborgconfig PCI_BIOS
27983c2362e6SHarvey Harrison	def_bool y
2799efefa6f6SIngo Molnar	depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2800e279b6c1SSam Ravnborg
2801e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2802e279b6c1SSam Ravnborgconfig PCI_DIRECT
28033c2362e6SHarvey Harrison	def_bool y
28040aba496fSShaohua Li	depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2805e279b6c1SSam Ravnborg
2806e279b6c1SSam Ravnborgconfig PCI_MMCONFIG
2807b45c9f36SJan Kiszka	bool "Support mmconfig PCI config space access" if X86_64
2808b45c9f36SJan Kiszka	default y
28094590d98fSAndy Shevchenko	depends on PCI && (ACPI || JAILHOUSE_GUEST)
2810b45c9f36SJan Kiszka	depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
2811e279b6c1SSam Ravnborg
28123ef0e1f8SAndres Salomonconfig PCI_OLPC
28132bdd1b03SAndres Salomon	def_bool y
28142bdd1b03SAndres Salomon	depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
28153ef0e1f8SAndres Salomon
2816b5401a96SAlex Nixonconfig PCI_XEN
2817b5401a96SAlex Nixon	def_bool y
2818b5401a96SAlex Nixon	depends on PCI && XEN
2819b5401a96SAlex Nixon
28208364e1f8SJan Kiszkaconfig MMCONF_FAM10H
28218364e1f8SJan Kiszka	def_bool y
28228364e1f8SJan Kiszka	depends on X86_64 && PCI_MMCONFIG && ACPI
2823e279b6c1SSam Ravnborg
28243f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK
28256a108a14SDavid Rientjes	bool "Read CNB20LE Host Bridge Windows" if EXPERT
28266ea30386SKees Cook	depends on PCI
28273f6ea84aSIra W. Snyder	help
28283f6ea84aSIra W. Snyder	  Read the PCI windows out of the CNB20LE host bridge. This allows
28293f6ea84aSIra W. Snyder	  PCI hotplug to work on systems with the CNB20LE chipset which do
28303f6ea84aSIra W. Snyder	  not have ACPI.
28313f6ea84aSIra W. Snyder
283264a5fed6SBjorn Helgaas	  There's no public spec for this chipset, and this functionality
283364a5fed6SBjorn Helgaas	  is known to be incomplete.
283464a5fed6SBjorn Helgaas
283564a5fed6SBjorn Helgaas	  You should say N unless you know you need this.
283664a5fed6SBjorn Helgaas
28373a495511SWilliam Breathitt Grayconfig ISA_BUS
283817a2a129SWilliam Breathitt Gray	bool "ISA bus support on modern systems" if EXPERT
28393a495511SWilliam Breathitt Gray	help
284017a2a129SWilliam Breathitt Gray	  Expose ISA bus device drivers and options available for selection and
284117a2a129SWilliam Breathitt Gray	  configuration. Enable this option if your target machine has an ISA
284217a2a129SWilliam Breathitt Gray	  bus. ISA is an older system, displaced by PCI and newer bus
284317a2a129SWilliam Breathitt Gray	  architectures -- if your target machine is modern, it probably does
284417a2a129SWilliam Breathitt Gray	  not have an ISA bus.
28453a495511SWilliam Breathitt Gray
28463a495511SWilliam Breathitt Gray	  If unsure, say N.
28473a495511SWilliam Breathitt Gray
28481c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA.
2849e279b6c1SSam Ravnborgconfig ISA_DMA_API
28501c00f016SDavid Rientjes	bool "ISA-style DMA support" if (X86_64 && EXPERT)
28511c00f016SDavid Rientjes	default y
28521c00f016SDavid Rientjes	help
28531c00f016SDavid Rientjes	  Enables ISA-style DMA support for devices requiring such controllers.
28541c00f016SDavid Rientjes	  If unsure, say Y.
2855e279b6c1SSam Ravnborg
285651e68d05SLinus Torvaldsif X86_32
285751e68d05SLinus Torvalds
2858e279b6c1SSam Ravnborgconfig ISA
2859e279b6c1SSam Ravnborg	bool "ISA support"
2860a7f7f624SMasahiro Yamada	help
2861e279b6c1SSam Ravnborg	  Find out whether you have ISA slots on your motherboard.  ISA is the
2862e279b6c1SSam Ravnborg	  name of a bus system, i.e. the way the CPU talks to the other stuff
2863e279b6c1SSam Ravnborg	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
2864e279b6c1SSam Ravnborg	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2865e279b6c1SSam Ravnborg	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
2866e279b6c1SSam Ravnborg
2867e279b6c1SSam Ravnborgconfig SCx200
2868e279b6c1SSam Ravnborg	tristate "NatSemi SCx200 support"
2869a7f7f624SMasahiro Yamada	help
2870e279b6c1SSam Ravnborg	  This provides basic support for National Semiconductor's
2871e279b6c1SSam Ravnborg	  (now AMD's) Geode processors.  The driver probes for the
2872e279b6c1SSam Ravnborg	  PCI-IDs of several on-chip devices, so its a good dependency
2873e279b6c1SSam Ravnborg	  for other scx200_* drivers.
2874e279b6c1SSam Ravnborg
2875e279b6c1SSam Ravnborg	  If compiled as a module, the driver is named scx200.
2876e279b6c1SSam Ravnborg
2877e279b6c1SSam Ravnborgconfig SCx200HR_TIMER
2878e279b6c1SSam Ravnborg	tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2879592913ecSJohn Stultz	depends on SCx200
2880e279b6c1SSam Ravnborg	default y
2881a7f7f624SMasahiro Yamada	help
2882e279b6c1SSam Ravnborg	  This driver provides a clocksource built upon the on-chip
2883e279b6c1SSam Ravnborg	  27MHz high-resolution timer.  Its also a workaround for
2884e279b6c1SSam Ravnborg	  NSC Geode SC-1100's buggy TSC, which loses time when the
2885e279b6c1SSam Ravnborg	  processor goes idle (as is done by the scheduler).  The
2886e279b6c1SSam Ravnborg	  other workaround is idle=poll boot option.
2887e279b6c1SSam Ravnborg
28883ef0e1f8SAndres Salomonconfig OLPC
28893ef0e1f8SAndres Salomon	bool "One Laptop Per Child support"
289054008979SThomas Gleixner	depends on !X86_PAE
28913c554946SAndres Salomon	select GPIOLIB
2892dc3119e7SThomas Gleixner	select OF
289345bb1674SDaniel Drake	select OF_PROMTREE
2894b4e51854SGrant Likely	select IRQ_DOMAIN
28950c3d931bSLubomir Rintel	select OLPC_EC
2896a7f7f624SMasahiro Yamada	help
28973ef0e1f8SAndres Salomon	  Add support for detecting the unique features of the OLPC
28983ef0e1f8SAndres Salomon	  XO hardware.
28993ef0e1f8SAndres Salomon
2900a3128588SDaniel Drakeconfig OLPC_XO1_PM
2901a3128588SDaniel Drake	bool "OLPC XO-1 Power Management"
2902fa112cf1SBorislav Petkov	depends on OLPC && MFD_CS5535=y && PM_SLEEP
2903a7f7f624SMasahiro Yamada	help
290497c4cb71SDaniel Drake	  Add support for poweroff and suspend of the OLPC XO-1 laptop.
2905bf1ebf00SDaniel Drake
2906cfee9597SDaniel Drakeconfig OLPC_XO1_RTC
2907cfee9597SDaniel Drake	bool "OLPC XO-1 Real Time Clock"
2908cfee9597SDaniel Drake	depends on OLPC_XO1_PM && RTC_DRV_CMOS
2909a7f7f624SMasahiro Yamada	help
2910cfee9597SDaniel Drake	  Add support for the XO-1 real time clock, which can be used as a
2911cfee9597SDaniel Drake	  programmable wakeup source.
2912cfee9597SDaniel Drake
29137feda8e9SDaniel Drakeconfig OLPC_XO1_SCI
29147feda8e9SDaniel Drake	bool "OLPC XO-1 SCI extras"
291592e830f2SArnd Bergmann	depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
2916ed8e47feSRandy Dunlap	depends on INPUT=y
2917d8d01a63SDaniel Drake	select POWER_SUPPLY
2918a7f7f624SMasahiro Yamada	help
29197feda8e9SDaniel Drake	  Add support for SCI-based features of the OLPC XO-1 laptop:
29207bc74b3dSDaniel Drake	   - EC-driven system wakeups
29217feda8e9SDaniel Drake	   - Power button
29227bc74b3dSDaniel Drake	   - Ebook switch
29232cf2baeaSDaniel Drake	   - Lid switch
2924e1040ac6SDaniel Drake	   - AC adapter status updates
2925e1040ac6SDaniel Drake	   - Battery status updates
29267feda8e9SDaniel Drake
2927a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI
2928a0f30f59SDaniel Drake	bool "OLPC XO-1.5 SCI extras"
2929d8d01a63SDaniel Drake	depends on OLPC && ACPI
2930d8d01a63SDaniel Drake	select POWER_SUPPLY
2931a7f7f624SMasahiro Yamada	help
2932a0f30f59SDaniel Drake	  Add support for SCI-based features of the OLPC XO-1.5 laptop:
2933a0f30f59SDaniel Drake	   - EC-driven system wakeups
2934a0f30f59SDaniel Drake	   - AC adapter status updates
2935a0f30f59SDaniel Drake	   - Battery status updates
2936e279b6c1SSam Ravnborg
2937d4f3e350SEd Wildgooseconfig ALIX
2938d4f3e350SEd Wildgoose	bool "PCEngines ALIX System Support (LED setup)"
2939d4f3e350SEd Wildgoose	select GPIOLIB
2940a7f7f624SMasahiro Yamada	help
2941d4f3e350SEd Wildgoose	  This option enables system support for the PCEngines ALIX.
2942d4f3e350SEd Wildgoose	  At present this just sets up LEDs for GPIO control on
2943d4f3e350SEd Wildgoose	  ALIX2/3/6 boards.  However, other system specific setup should
2944d4f3e350SEd Wildgoose	  get added here.
2945d4f3e350SEd Wildgoose
2946d4f3e350SEd Wildgoose	  Note: You must still enable the drivers for GPIO and LED support
2947d4f3e350SEd Wildgoose	  (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2948d4f3e350SEd Wildgoose
2949d4f3e350SEd Wildgoose	  Note: You have to set alix.force=1 for boards with Award BIOS.
2950d4f3e350SEd Wildgoose
2951da4e3302SPhilip Prindevilleconfig NET5501
2952da4e3302SPhilip Prindeville	bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2953da4e3302SPhilip Prindeville	select GPIOLIB
2954a7f7f624SMasahiro Yamada	help
2955da4e3302SPhilip Prindeville	  This option enables system support for the Soekris Engineering net5501.
2956da4e3302SPhilip Prindeville
29573197059aSPhilip A. Prindevilleconfig GEOS
29583197059aSPhilip A. Prindeville	bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
29593197059aSPhilip A. Prindeville	select GPIOLIB
29603197059aSPhilip A. Prindeville	depends on DMI
2961a7f7f624SMasahiro Yamada	help
29623197059aSPhilip A. Prindeville	  This option enables system support for the Traverse Technologies GEOS.
29633197059aSPhilip A. Prindeville
29647d029125SVivien Didelotconfig TS5500
29657d029125SVivien Didelot	bool "Technologic Systems TS-5500 platform support"
29667d029125SVivien Didelot	depends on MELAN
29677d029125SVivien Didelot	select CHECK_SIGNATURE
29687d029125SVivien Didelot	select NEW_LEDS
29697d029125SVivien Didelot	select LEDS_CLASS
2970a7f7f624SMasahiro Yamada	help
29717d029125SVivien Didelot	  This option enables system support for the Technologic Systems TS-5500.
29727d029125SVivien Didelot
2973e279b6c1SSam Ravnborgendif # X86_32
2974e279b6c1SSam Ravnborg
297523ac4ae8SAndreas Herrmannconfig AMD_NB
2976e279b6c1SSam Ravnborg	def_bool y
29770e152cd7SBorislav Petkov	depends on CPU_SUP_AMD && PCI
2978e279b6c1SSam Ravnborg
2979e279b6c1SSam Ravnborgendmenu
2980e279b6c1SSam Ravnborg
29811572497cSChristoph Hellwigmenu "Binary Emulations"
2982e279b6c1SSam Ravnborg
2983e279b6c1SSam Ravnborgconfig IA32_EMULATION
2984e279b6c1SSam Ravnborg	bool "IA32 Emulation"
2985e279b6c1SSam Ravnborg	depends on X86_64
298639f88911SIngo Molnar	select ARCH_WANT_OLD_COMPAT_IPC
2987d1603990SRandy Dunlap	select BINFMT_ELF
298839f88911SIngo Molnar	select COMPAT_OLD_SIGACTION
2989a7f7f624SMasahiro Yamada	help
29905fd92e65SH. J. Lu	  Include code to run legacy 32-bit programs under a
29915fd92e65SH. J. Lu	  64-bit kernel. You should likely turn this on, unless you're
29925fd92e65SH. J. Lu	  100% sure that you don't have any 32-bit programs left.
2993e279b6c1SSam Ravnborg
299483a44a4fSMasahiro Yamadaconfig X86_X32_ABI
29956ea30386SKees Cook	bool "x32 ABI for 64-bit mode"
29969b54050bSBrian Gerst	depends on X86_64
2997aaeed6ecSNathan Chancellor	# llvm-objcopy does not convert x86_64 .note.gnu.property or
2998aaeed6ecSNathan Chancellor	# compressed debug sections to x86_x32 properly:
2999aaeed6ecSNathan Chancellor	# https://github.com/ClangBuiltLinux/linux/issues/514
3000aaeed6ecSNathan Chancellor	# https://github.com/ClangBuiltLinux/linux/issues/1141
3001aaeed6ecSNathan Chancellor	depends on $(success,$(OBJCOPY) --version | head -n1 | grep -qv llvm)
3002a7f7f624SMasahiro Yamada	help
30035fd92e65SH. J. Lu	  Include code to run binaries for the x32 native 32-bit ABI
30045fd92e65SH. J. Lu	  for 64-bit processors.  An x32 process gets access to the
30055fd92e65SH. J. Lu	  full 64-bit register file and wide data path while leaving
30065fd92e65SH. J. Lu	  pointers at 32 bits for smaller memory footprint.
30075fd92e65SH. J. Lu
3008953fee1dSIngo Molnarconfig COMPAT_32
3009953fee1dSIngo Molnar	def_bool y
3010953fee1dSIngo Molnar	depends on IA32_EMULATION || X86_32
3011953fee1dSIngo Molnar	select HAVE_UID16
3012953fee1dSIngo Molnar	select OLD_SIGSUSPEND3
3013953fee1dSIngo Molnar
3014e279b6c1SSam Ravnborgconfig COMPAT
30153c2362e6SHarvey Harrison	def_bool y
301683a44a4fSMasahiro Yamada	depends on IA32_EMULATION || X86_X32_ABI
3017e279b6c1SSam Ravnborg
3018e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT
30193120e25eSJan Beulich	def_bool y
3020a9251280SLinus Torvalds	depends on COMPAT
3021ee009e4aSDavid Howells
3022e279b6c1SSam Ravnborgendmenu
3023e279b6c1SSam Ravnborg
3024e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP
3025e5beae16SKeith Packard	def_bool y
3026e5beae16SKeith Packard	depends on X86_32
3027e5beae16SKeith Packard
3028edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig"
30295e8ebd84SJason A. Donenfeld
30305e8ebd84SJason A. Donenfeldsource "arch/x86/Kconfig.assembler"
3031