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Greg Kroah-Hartmanb2441312017-11-01 15:07:57 +01001# SPDX-License-Identifier: GPL-2.0
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01002# Select 32 or 64 bit
3config 64BIT
Masahiro Yamada104daea2018-05-28 18:21:40 +09004 bool "64-bit kernel" if "$(ARCH)" = "x86"
5 default "$(ARCH)" != "i386"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01006 ---help---
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01007 Say yes to build a 64-bit kernel - formerly known as x86_64
8 Say no to build a 32-bit kernel - formerly known as i386
9
10config X86_32
Jan Beulich3120e252012-09-10 12:41:45 +010011 def_bool y
12 depends on !64BIT
Ingo Molnar341c7872016-11-15 10:04:55 +010013 # Options that are inherently 32-bit kernel only:
14 select ARCH_WANT_IPC_PARSE_VERSION
15 select CLKSRC_I8253
16 select CLONE_BACKWARDS
17 select HAVE_AOUT
18 select HAVE_GENERIC_DMA_COHERENT
19 select MODULES_USE_ELF_REL
20 select OLD_SIGACTION
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +010021
22config X86_64
Jan Beulich3120e252012-09-10 12:41:45 +010023 def_bool y
24 depends on 64BIT
Ingo Molnard94e0682016-11-15 10:11:57 +010025 # Options that are inherently 64-bit kernel only:
Aneesh Kumar K.Ve1073d12017-07-06 15:39:17 -070026 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
Ingo Molnard94e0682016-11-15 10:11:57 +010027 select ARCH_SUPPORTS_INT128
28 select ARCH_USE_CMPXCHG_LOCKREF
29 select HAVE_ARCH_SOFT_DIRTY
30 select MODULES_USE_ELF_RELA
Christoph Hellwigf616ab52018-05-09 06:53:49 +020031 select NEED_DMA_MAP_STATE
Christoph Hellwig09230cb2018-04-24 09:00:54 +020032 select SWIOTLB
Ingo Molnard94e0682016-11-15 10:11:57 +010033 select X86_DEV_DMA_OPS
Dominik Brodowskif8781c42018-04-05 11:53:05 +020034 select ARCH_HAS_SYSCALL_WRAPPER
Sam Ravnborg1032c0b2007-11-06 21:35:08 +010035
Ingo Molnard94e0682016-11-15 10:11:57 +010036#
37# Arch settings
38#
39# ( Note that options that are marked 'if X86_64' could in principle be
40# ported to 32-bit as well. )
41#
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +010042config X86
Harvey Harrison3c2362e2008-01-30 13:31:03 +010043 def_bool y
Ingo Molnarc763ea22016-11-15 10:26:39 +010044 #
45 # Note: keep this list sorted alphabetically
46 #
Ingo Molnar6471b822015-06-03 10:00:13 +020047 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
48 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
49 select ANON_INODES
50 select ARCH_CLOCKSOURCE_DATA
51 select ARCH_DISCARD_MEMBLOCK
Ingo Molnarc763ea22016-11-15 10:26:39 +010052 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
Laura Abbottfa5b6ec2017-01-10 13:35:40 -080053 select ARCH_HAS_DEBUG_VIRTUAL
Dan Williams21266be2015-11-19 18:19:29 -080054 select ARCH_HAS_DEVMEM_IS_ALLOWED
Ingo Molnar6471b822015-06-03 10:00:13 +020055 select ARCH_HAS_ELF_RANDOMIZE
Linus Torvalds72d93102014-09-13 11:14:53 -070056 select ARCH_HAS_FAST_MULTIPLIER
Dave Hansen316d0972018-04-20 15:20:28 -070057 select ARCH_HAS_FILTER_PGPROT
Daniel Micay6974f0c2017-07-12 14:36:10 -070058 select ARCH_HAS_FORTIFY_SOURCE
Riku Voipio957e3fa2014-12-12 16:57:44 -080059 select ARCH_HAS_GCOV_PROFILE_ALL
Dmitry Vyukov5c9a8752016-03-22 14:27:30 -070060 select ARCH_HAS_KCOV if X86_64
Mathieu Desnoyers10bcc802018-01-29 15:20:18 -050061 select ARCH_HAS_MEMBARRIER_SYNC_CORE
Ingo Molnarc763ea22016-11-15 10:26:39 +010062 select ARCH_HAS_PMEM_API if X86_64
Laurent Dufour3010a5e2018-06-07 17:06:08 -070063 select ARCH_HAS_PTE_SPECIAL
Kees Cook39208aa2017-09-02 13:09:46 -070064 select ARCH_HAS_REFCOUNT
Dan Williams0aed55a2017-05-29 12:22:50 -070065 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Dan Williams092b31a2018-07-08 13:46:17 -070066 select ARCH_HAS_UACCESS_MCSAFE if X86_64 && X86_MCE
Daniel Borkmannd2852a22017-02-21 16:09:33 +010067 select ARCH_HAS_SET_MEMORY
Ingo Molnar6471b822015-06-03 10:00:13 +020068 select ARCH_HAS_SG_CHAIN
Laura Abbottad21fc42017-02-06 16:31:57 -080069 select ARCH_HAS_STRICT_KERNEL_RWX
70 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050071 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Andrey Ryabininc6d30852016-01-20 15:00:55 -080072 select ARCH_HAS_UBSAN_SANITIZE_ALL
Oliver O'Halloran65f7d042017-06-28 11:32:31 +100073 select ARCH_HAS_ZONE_DEVICE if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020074 select ARCH_HAVE_NMI_SAFE_CMPXCHG
75 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040076 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080077 select ARCH_MIGHT_HAVE_PC_SERIO
Arnd Bergmann2c870e62018-07-24 11:48:45 +020078 select ARCH_SUPPORTS_ACPI
Ingo Molnar6471b822015-06-03 10:00:13 +020079 select ARCH_SUPPORTS_ATOMIC_RMW
Ingo Molnar6471b822015-06-03 10:00:13 +020080 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
81 select ARCH_USE_BUILTIN_BSWAP
Ingo Molnar6471b822015-06-03 10:00:13 +020082 select ARCH_USE_QUEUED_RWLOCKS
83 select ARCH_USE_QUEUED_SPINLOCKS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -070084 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Ingo Molnarc763ea22016-11-15 10:26:39 +010085 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Huang Ying38d8b4e2017-07-06 15:37:18 -070086 select ARCH_WANTS_THP_SWAP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020087 select BUILDTIME_EXTABLE_SORT
88 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +020089 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
90 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +020091 select DCACHE_WORD_ACCESS
Christoph Hellwigfec777c2018-03-19 11:38:15 +010092 select DMA_DIRECT_OPS
Linus Torvalds45471cd2015-06-24 19:52:06 -070093 select EDAC_ATOMIC_SCRUB
94 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +020095 select GENERIC_CLOCKEVENTS
96 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
97 select GENERIC_CLOCKEVENTS_MIN_ADJUST
98 select GENERIC_CMOS_UPDATE
99 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +0100100 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +0200101 select GENERIC_EARLY_IOREMAP
102 select GENERIC_FIND_FIRST_BIT
103 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +0200104 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +0200105 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +0200106 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200107 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200108 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200109 select GENERIC_IRQ_SHOW
110 select GENERIC_PENDING_IRQ if SMP
111 select GENERIC_SMP_IDLE_THREAD
112 select GENERIC_STRNCPY_FROM_USER
113 select GENERIC_STRNLEN_USER
114 select GENERIC_TIME_VSYSCALL
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200115 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200116 select HAVE_ACPI_APEI if ACPI
117 select HAVE_ACPI_APEI_NMI if ACPI
118 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200119 select HAVE_ARCH_AUDITSYSCALL
120 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
121 select HAVE_ARCH_JUMP_LABEL
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800122 select HAVE_ARCH_KASAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200123 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800124 select HAVE_ARCH_MMAP_RND_BITS if MMU
125 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300126 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ard Biesheuvel271ca782018-08-21 21:56:00 -0700127 select HAVE_ARCH_PREL32_RELOCATIONS
Ingo Molnar6471b822015-06-03 10:00:13 +0200128 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700129 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Ingo Molnar6471b822015-06-03 10:00:13 +0200130 select HAVE_ARCH_TRACEHOOK
131 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Matthew Wilcoxa00cc7d2017-02-24 14:57:02 -0800132 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
Andy Lutomirskie37e43a2016-08-11 02:35:23 -0700133 select HAVE_ARCH_VMAP_STACK if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100134 select HAVE_ARCH_WITHIN_STACK_FRAMES
Ingo Molnar6471b822015-06-03 10:00:13 +0200135 select HAVE_CMPXCHG_DOUBLE
136 select HAVE_CMPXCHG_LOCAL
137 select HAVE_CONTEXT_TRACKING if X86_64
Josh Triplettc1bd55f2015-06-30 15:00:00 -0700138 select HAVE_COPY_THREAD_TLS
Ingo Molnar6471b822015-06-03 10:00:13 +0200139 select HAVE_C_RECORDMCOUNT
140 select HAVE_DEBUG_KMEMLEAK
141 select HAVE_DEBUG_STACKOVERFLOW
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700142 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400143 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900144 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Wang YanQing03f57812018-05-03 14:10:43 +0800145 select HAVE_EBPF_JIT
Johannes Berg58340a02008-07-25 01:45:33 -0700146 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Jiri Slaby5f56a5d2016-05-20 17:00:16 -0700147 select HAVE_EXIT_THREAD
Steven Rostedt (VMware)644e0e82017-03-23 10:33:52 -0400148 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
Ingo Molnar6471b822015-06-03 10:00:13 +0200149 select HAVE_FTRACE_MCOUNT_RECORD
Ingo Molnar6471b822015-06-03 10:00:13 +0200150 select HAVE_FUNCTION_GRAPH_TRACER
151 select HAVE_FUNCTION_TRACER
Emese Revfy6b90bd42016-05-24 00:09:38 +0200152 select HAVE_GCC_PLUGINS
K.Prasad0067f122009-06-01 23:43:57 +0530153 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200154 select HAVE_IDE
155 select HAVE_IOREMAP_PROT
156 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
157 select HAVE_IRQ_TIME_ACCOUNTING
158 select HAVE_KERNEL_BZIP2
159 select HAVE_KERNEL_GZIP
160 select HAVE_KERNEL_LZ4
161 select HAVE_KERNEL_LZMA
162 select HAVE_KERNEL_LZO
163 select HAVE_KERNEL_XZ
164 select HAVE_KPROBES
165 select HAVE_KPROBES_ON_FTRACE
Masami Hiramatsu540adea2018-01-13 02:55:03 +0900166 select HAVE_FUNCTION_ERROR_INJECTION
Ingo Molnar6471b822015-06-03 10:00:13 +0200167 select HAVE_KRETPROBES
168 select HAVE_KVM
169 select HAVE_LIVEPATCH if X86_64
170 select HAVE_MEMBLOCK
171 select HAVE_MEMBLOCK_NODE_MAP
Frederic Weisbecker01027522010-04-11 18:55:56 +0200172 select HAVE_MIXED_BREAKPOINTS_REGS
Josh Poimboeufee9f8fc2017-07-24 18:36:57 -0500173 select HAVE_MOD_ARCH_SPECIFIC
Petr Mladek42a0bb32016-05-20 17:00:33 -0700174 select HAVE_NMI
Ingo Molnar6471b822015-06-03 10:00:13 +0200175 select HAVE_OPROFILE
176 select HAVE_OPTPROBES
177 select HAVE_PCSPKR_PLATFORM
178 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200179 select HAVE_PERF_EVENTS_NMI
Nicholas Piggin92e5aae2017-08-18 15:15:51 -0700180 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
Jiri Olsac5e63192012-08-07 15:20:36 +0200181 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200182 select HAVE_PERF_USER_STACK_DUMP
Peter Zijlstra48a8b972018-08-22 17:30:16 +0200183 select HAVE_RCU_TABLE_FREE if PARAVIRT
Peter Zijlstrad86564a2018-08-22 17:30:15 +0200184 select HAVE_RCU_TABLE_INVALIDATE if HAVE_RCU_TABLE_FREE
Ingo Molnar6471b822015-06-03 10:00:13 +0200185 select HAVE_REGS_AND_STACK_ACCESS_API
Jiri Slaby6415b382018-05-18 08:47:13 +0200186 select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION
Masahiro Yamadad148eac2018-06-14 19:36:45 +0900187 select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
Ingo Molnarc763ea22016-11-15 10:26:39 +0100188 select HAVE_STACK_VALIDATION if X86_64
Mathieu Desnoyersd6761b82018-06-02 08:43:58 -0400189 select HAVE_RSEQ
Ingo Molnar6471b822015-06-03 10:00:13 +0200190 select HAVE_SYSCALL_TRACEPOINTS
Ingo Molnar6471b822015-06-03 10:00:13 +0200191 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300192 select HAVE_USER_RETURN_NOTIFIER
Thomas Gleixner05736e42018-05-29 17:48:27 +0200193 select HOTPLUG_SMT if SMP
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100194 select IRQ_FORCED_THREADING
Christoph Hellwig86596f02018-04-05 09:44:52 +0200195 select NEED_SG_DMA_LENGTH
Thomas Gleixnerdf65c1b2017-03-16 22:50:07 +0100196 select PCI_LOCKLESS_CONFIG
Ingo Molnar6471b822015-06-03 10:00:13 +0200197 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500198 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200199 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200200 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500201 select SRCU
Ingo Molnar6471b822015-06-03 10:00:13 +0200202 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700203 select THREAD_INFO_IN_TASK
Ingo Molnar6471b822015-06-03 10:00:13 +0200204 select USER_STACKTRACE_SUPPORT
205 select VIRT_TO_BUS
Ingo Molnar6471b822015-06-03 10:00:13 +0200206 select X86_FEATURE_NAMES if PROC_FS
Balbir Singh7d8330a2008-02-10 12:46:28 +0530207
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200208config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100209 def_bool y
210 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200211
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700212config OUTPUT_FORMAT
213 string
214 default "elf32-i386" if X86_32
215 default "elf64-x86-64" if X86_64
216
Sam Ravnborg73531902008-05-25 23:03:18 +0200217config ARCH_DEFCONFIG
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200218 string
Sam Ravnborg73531902008-05-25 23:03:18 +0200219 default "arch/x86/configs/i386_defconfig" if X86_32
220 default "arch/x86/configs/x86_64_defconfig" if X86_64
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200221
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100222config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100223 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100224
225config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100226 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100227
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100228config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100229 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100230
Daniel Cashman9e08f572016-01-14 15:20:06 -0800231config ARCH_MMAP_RND_BITS_MIN
232 default 28 if 64BIT
233 default 8
234
235config ARCH_MMAP_RND_BITS_MAX
236 default 32 if 64BIT
237 default 16
238
239config ARCH_MMAP_RND_COMPAT_BITS_MIN
240 default 8
241
242config ARCH_MMAP_RND_COMPAT_BITS_MAX
243 default 16
244
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100245config SBUS
246 bool
247
248config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100249 def_bool y
250 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100251
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100252config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100253 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100254 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000255 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
256
257config GENERIC_BUG_RELATIVE_POINTERS
258 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100259
260config GENERIC_HWEIGHT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100261 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100262
263config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100264 def_bool y
265 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100266
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100267config RWSEM_XCHGADD_ALGORITHM
Jan Beulich3120e252012-09-10 12:41:45 +0100268 def_bool y
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100269
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100270config GENERIC_CALIBRATE_DELAY
271 def_bool y
272
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800273config ARCH_HAS_CPU_RELAX
274 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100275
Pekka Enberg1b27d052008-04-28 02:12:22 -0700276config ARCH_HAS_CACHE_LINE_SIZE
277 def_bool y
278
Dave Hansen316d0972018-04-20 15:20:28 -0700279config ARCH_HAS_FILTER_PGPROT
280 def_bool y
281
Mike Travisdd5af902008-01-30 13:33:32 +0100282config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900283 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100284
Tejun Heo08fc4582009-08-14 15:00:49 +0900285config NEED_PER_CPU_EMBED_FIRST_CHUNK
286 def_bool y
287
288config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900289 def_bool y
290
Johannes Berg801e4062007-12-08 02:12:39 +0100291config ARCH_HIBERNATION_POSSIBLE
292 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100293
Johannes Bergf4cb5702007-12-08 02:14:00 +0100294config ARCH_SUSPEND_POSSIBLE
295 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100296
Steve Cappercfe28c52013-04-29 14:29:48 +0100297config ARCH_WANT_HUGE_PMD_SHARE
298 def_bool y
299
Steve Capper53313b22013-04-30 08:03:42 +0100300config ARCH_WANT_GENERAL_HUGETLB
301 def_bool y
302
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100303config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000304 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100305
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100306config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000307 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100308
Ingo Molnar765c68b2008-04-09 11:03:37 +0200309config ARCH_SUPPORTS_OPTIMIZED_INLINING
310 def_bool y
311
Akinobu Mita6a11f752009-03-31 15:23:17 -0700312config ARCH_SUPPORTS_DEBUG_PAGEALLOC
313 def_bool y
314
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300315config KASAN_SHADOW_OFFSET
316 hex
317 depends on KASAN
318 default 0xdffffc0000000000
319
Shane Wang69575d32009-09-01 18:25:07 -0700320config HAVE_INTEL_TXT
321 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700322 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700323
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100324config X86_32_SMP
325 def_bool y
326 depends on X86_32 && SMP
327
328config X86_64_SMP
329 def_bool y
330 depends on X86_64 && SMP
331
Tejun Heoccbeed32009-02-09 22:17:40 +0900332config X86_32_LAZY_GS
333 def_bool y
Masahiro Yamada8458f8c2018-06-14 19:36:43 +0900334 depends on X86_32 && !STACKPROTECTOR
Tejun Heoccbeed32009-02-09 22:17:40 +0900335
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530336config ARCH_SUPPORTS_UPROBES
337 def_bool y
338
Rob Herringd20642f2014-04-18 17:19:54 -0500339config FIX_EARLYCON_MEM
340 def_bool y
341
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +0300342config DYNAMIC_PHYSICAL_MASK
343 bool
344
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700345config PGTABLE_LEVELS
346 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300347 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700348 default 4 if X86_64
349 default 3 if X86_PAE
350 default 2
351
Masahiro Yamada2a61f472018-05-28 18:22:00 +0900352config CC_HAS_SANE_STACKPROTECTOR
353 bool
354 default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
355 default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
356 help
357 We have to make sure stack protector is unconditionally disabled if
358 the compiler produces broken code.
359
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100360menu "Processor type and features"
361
Randy Dunlap5ee71532012-01-16 11:57:18 -0800362config ZONE_DMA
363 bool "DMA memory allocation support" if EXPERT
364 default y
365 help
366 DMA memory allocation support allows devices with less than 32-bit
367 addressing to allocate within the first 16MB of address space.
368 Disable if no such devices will be used.
369
370 If unsure, say Y.
371
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100372config SMP
373 bool "Symmetric multi-processing support"
374 ---help---
375 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800376 a system with only one CPU, say N. If you have a system with more
377 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100378
Robert Graffham4a474152014-01-23 15:55:29 -0800379 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100380 machines, but will use only one CPU of a multiprocessor machine. If
381 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800382 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100383 will run faster if you say N here.
384
385 Note that if you say Y here and choose architecture "586" or
386 "Pentium" under "Processor family", the kernel will not work on 486
387 architectures. Similarly, multiprocessor kernels for the "PPro"
388 architecture may not work on all Pentium based boards.
389
390 People using multiprocessor machines who say Y here should also say
391 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
392 Management" code will be disabled if you say Y here.
393
Paul Bolle395cf962011-08-15 02:02:26 +0200394 See also <file:Documentation/x86/i386/IO-APIC.txt>,
Benjamin Petersonc9525a32017-05-20 17:20:16 -0700395 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100396 <http://www.tldp.org/docs.html#howto>.
397
398 If you don't know what to do here, say N.
399
Josh Triplett9def39be2013-10-30 08:09:45 -0700400config X86_FEATURE_NAMES
401 bool "Processor feature human-readable names" if EMBEDDED
402 default y
403 ---help---
404 This option compiles in a table of x86 feature bits and corresponding
405 names. This is required to support /proc/cpuinfo and a few kernel
406 messages. You can disable this to save space, at the expense of
407 making those few kernel messages show numeric feature bits instead.
408
409 If in doubt, say Y.
410
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800411config X86_X2APIC
412 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200413 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800414 ---help---
415 This enables x2apic support on CPUs that have this feature.
416
417 This allows 32-bit apic IDs (so it can support very large systems),
418 and accesses the local apic via MSRs not via mmio.
419
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800420 If you don't know what to do here, say N.
421
Yinghai Lu6695c852008-06-19 12:13:09 -0700422config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700423 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000424 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200425 depends on X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100426 ---help---
Yinghai Lu6695c852008-06-19 12:13:09 -0700427 For old smp systems that do not have proper acpi support. Newer systems
428 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700429
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000430config GOLDFISH
431 def_bool y
432 depends on X86_GOLDFISH
433
David Woodhouse76b04382018-01-11 21:46:25 +0000434config RETPOLINE
435 bool "Avoid speculative indirect branches in kernel"
436 default y
Peter Zijlstrad5028ba2018-02-06 09:46:13 +0100437 select STACK_VALIDATION if HAVE_STACK_VALIDATION
David Woodhouse76b04382018-01-11 21:46:25 +0000438 help
439 Compile kernel with the retpoline compiler options to guard against
440 kernel-to-user data leaks by avoiding speculative indirect
441 branches. Requires a compiler with -mindirect-branch=thunk-extern
442 support for full protection. The kernel may run slower.
443
444 Without compiler support, at least indirect branches in assembler
445 code are eliminated. Since this includes the syscall entry path,
446 it is not entirely pointless.
447
Vikas Shivappaf01d7d52017-07-25 14:14:22 -0700448config INTEL_RDT
449 bool "Intel Resource Director Technology support"
Fenghua Yu78e99b42016-10-22 06:19:53 -0700450 default n
451 depends on X86 && CPU_SUP_INTEL
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100452 select KERNFS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700453 help
Vikas Shivappaf01d7d52017-07-25 14:14:22 -0700454 Select to enable resource allocation and monitoring which are
455 sub-features of Intel Resource Director Technology(RDT). More
456 information about RDT can be found in the Intel x86
457 Architecture Software Developer Manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700458
459 Say N if unsure.
460
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800461if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800462config X86_BIGSMP
463 bool "Support for big SMP systems with more than 8 CPUs"
464 depends on SMP
465 ---help---
466 This option is needed for the systems that have more than 8 CPUs
467
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800468config X86_EXTENDED_PLATFORM
469 bool "Support for extended (non-PC) x86 platforms"
470 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100471 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100472 If you disable this option then the kernel will only support
473 standard PC platforms. (which covers the vast majority of
474 systems out there.)
475
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800476 If you enable this option then you'll be able to select support
477 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100478 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800479 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800480 RDC R-321x SoC
481 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200482 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200483 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100484
485 If you have one of these systems, or if you want to build a
486 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800487endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100488
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800489if X86_64
490config X86_EXTENDED_PLATFORM
491 bool "Support for extended (non-PC) x86 platforms"
492 default y
493 ---help---
494 If you disable this option then the kernel will only support
495 standard PC platforms. (which covers the vast majority of
496 systems out there.)
497
498 If you enable this option then you'll be able to select support
499 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800500 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800501 ScaleMP vSMP
502 SGI Ultraviolet
503
504 If you have one of these systems, or if you want to build a
505 generic distribution kernel, say Y here - otherwise say N.
506endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800507# This is an alphabetically sorted list of 64 bit extended platforms
508# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800509config X86_NUMACHIP
510 bool "Numascale NumaChip"
511 depends on X86_64
512 depends on X86_EXTENDED_PLATFORM
513 depends on NUMA
514 depends on SMP
515 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700516 depends on PCI_MMCONFIG
Steffen Persvold44b111b52011-12-06 00:07:26 +0800517 ---help---
518 Adds support for Numascale NumaChip large-SMP systems. Needed to
519 enable more than ~168 cores.
520 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100521
Ingo Molnar6a485652009-01-27 18:29:13 +0100522config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800523 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100524 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100525 select PARAVIRT
526 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800527 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300528 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100529 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100530 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
531 supposed to run on these EM64T-based machines. Only choose this option
532 if you have one of these machines.
533
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800534config X86_UV
535 bool "SGI Ultraviolet"
536 depends on X86_64
537 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500538 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800539 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700540 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200541 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800542 ---help---
543 This option is needed in order to support SGI Ultraviolet systems.
544 If you don't have one of these, you should say N here.
545
546# Following is an alphabetically sorted list of 32 bit extended platforms
547# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100548
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000549config X86_GOLDFISH
550 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100551 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000552 ---help---
553 Enable support for the Goldfish virtual platform used primarily
554 for Android development. Unless you are building for the Android
555 Goldfish emulator say N here.
556
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800557config X86_INTEL_CE
558 bool "CE4100 TV platform"
559 depends on PCI
560 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800561 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800562 depends on X86_32
563 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800564 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100565 select OF
566 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800567 ---help---
568 Select for the Intel CE media processor (CE4100) SOC.
569 This option compiles in support for the CE4100 SOC for settop
570 boxes and media devices.
571
David Cohen4cb9b002013-12-16 17:37:26 -0800572config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100573 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100574 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800575 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000576 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200577 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000578 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000579 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800580 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000581 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000582 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000583 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000584 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000585 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800586 Select to build a kernel capable of supporting Intel MID (Mobile
587 Internet Device) platform systems which do not have the PCI legacy
588 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000589
David Cohen4cb9b002013-12-16 17:37:26 -0800590 Intel MID platforms are based on an Intel processor and chipset which
591 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100592
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000593config X86_INTEL_QUARK
594 bool "Intel Quark platform support"
595 depends on X86_32
596 depends on X86_EXTENDED_PLATFORM
597 depends on X86_PLATFORM_DEVICES
598 depends on X86_TSC
599 depends on PCI
600 depends on PCI_GOANY
601 depends on X86_IO_APIC
602 select IOSF_MBI
603 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200604 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000605 ---help---
606 Select to include support for Quark X1000 SoC.
607 Say Y here if you have a Quark based system such as the Arduino
608 compatible Intel Galileo.
609
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000610config X86_INTEL_LPSS
611 bool "Intel Low Power Subsystem Support"
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100612 depends on X86 && ACPI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000613 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300614 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100615 select IOSF_MBI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000616 ---help---
617 Select to build support for Intel Low Power Subsystem such as
618 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300619 things like clock tree (common clock framework) and pincontrol
620 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000621
Ken Xue92082a82015-02-06 08:27:51 +0800622config X86_AMD_PLATFORM_DEVICE
623 bool "AMD ACPI2Platform devices support"
624 depends on ACPI
625 select COMMON_CLK
626 select PINCTRL
627 ---help---
628 Select to interpret AMD specific ACPI device to platform device
629 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
630 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
631 implemented under PINCTRL subsystem.
632
David E. Boxced3ce72014-09-17 22:13:50 -0700633config IOSF_MBI
634 tristate "Intel SoC IOSF Sideband support for SoC platforms"
635 depends on PCI
636 ---help---
637 This option enables sideband register access support for Intel SoC
638 platforms. On these platforms the IOSF sideband is used in lieu of
639 MSR's for some register accesses, mostly but not limited to thermal
640 and power. Drivers may query the availability of this device to
641 determine if they need the sideband in order to work on these
642 platforms. The sideband is available on the following SoC products.
643 This list is not meant to be exclusive.
644 - BayTrail
645 - Braswell
646 - Quark
647
648 You should say Y if you are running a kernel on one of these SoC's.
649
David E. Boxed2226b2014-09-17 22:13:51 -0700650config IOSF_MBI_DEBUG
651 bool "Enable IOSF sideband access through debugfs"
652 depends on IOSF_MBI && DEBUG_FS
653 ---help---
654 Select this option to expose the IOSF sideband access registers (MCR,
655 MDR, MCRX) through debugfs to write and read register information from
656 different units on the SoC. This is most useful for obtaining device
657 state information for debug and analysis. As this is a general access
658 mechanism, users of this option would have specific knowledge of the
659 device they want to access.
660
661 If you don't require the option or are in doubt, say N.
662
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800663config X86_RDC321X
664 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100665 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800666 depends on X86_EXTENDED_PLATFORM
667 select M486
668 select X86_REBOOTFIXUPS
669 ---help---
670 This option is needed for RDC R-321x system-on-chip, also known
671 as R-8610-(G).
672 If you don't have one of these chips, you should say N here.
673
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100674config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100675 bool "Support non-standard 32-bit SMP architectures"
676 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800677 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100678 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800679 This option compiles in the bigsmp and STA2X11 default
680 subarchitectures. It is intended for a generic binary
681 kernel. If you select them all, kernel will probe it one by
682 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700683
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800684# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700685
Linus Torvaldsd949f362009-09-26 09:35:07 -0700686config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100687 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700688 # MCE code calls memory_failure():
689 depends on X86_MCE
690 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700691 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
692 depends on X86_64 || !SPARSEMEM
693 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700694
Alessandro Rubini83125a32012-04-04 19:40:21 +0200695config STA2X11
696 bool "STA2X11 Companion Chip Support"
697 depends on X86_32_NON_STANDARD && PCI
Christoph Hellwigb6e05472018-03-19 11:38:24 +0100698 select ARCH_HAS_PHYS_TO_DMA
Alessandro Rubini83125a32012-04-04 19:40:21 +0200699 select X86_DEV_DMA_OPS
700 select X86_DMA_REMAP
701 select SWIOTLB
702 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200703 select GPIOLIB
Alessandro Rubini83125a32012-04-04 19:40:21 +0200704 default n
705 ---help---
706 This adds support for boards based on the STA2X11 IO-Hub,
707 a.k.a. "ConneXt". The chip is used in place of the standard
708 PC chipset, so all "standard" peripherals are missing. If this
709 option is selected the kernel will still be able to boot on
710 standard PC machines.
711
Shérab82148d12010-09-25 06:06:57 +0200712config X86_32_IRIS
713 tristate "Eurobraille/Iris poweroff module"
714 depends on X86_32
715 ---help---
716 The Iris machines from EuroBraille do not have APM or ACPI support
717 to shut themselves down properly. A special I/O sequence is
718 needed to do so, which is what this module does at
719 kernel shutdown.
720
721 This is only for Iris machines from EuroBraille.
722
723 If unused, say N.
724
Ingo Molnarae1e9132008-11-11 09:05:16 +0100725config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100726 def_bool y
727 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800728 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100729 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100730 Calculate simpler /proc/<PID>/wchan values. If this option
731 is disabled then wchan values will recurse back to the
732 caller function. This provides more accurate wchan values,
733 at the expense of slightly more scheduling overhead.
734
735 If in doubt, say "Y".
736
Borislav Petkov6276a072013-03-04 21:20:21 +0100737menuconfig HYPERVISOR_GUEST
738 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100739 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100740 Say Y here to enable options for running Linux under various hyper-
741 visors. This option enables basic hypervisor detection and platform
742 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100743
Borislav Petkov6276a072013-03-04 21:20:21 +0100744 If you say N, all options in this submenu will be skipped and
745 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100746
Borislav Petkov6276a072013-03-04 21:20:21 +0100747if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100748
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100749config PARAVIRT
750 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100751 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100752 This changes the kernel so it can modify itself when it is run
753 under a hypervisor, potentially improving performance significantly
754 over full virtualization. However, when run without a hypervisor
755 the kernel is theoretically slower and slightly larger.
756
Borislav Petkov6276a072013-03-04 21:20:21 +0100757config PARAVIRT_DEBUG
758 bool "paravirt-ops debugging"
759 depends on PARAVIRT && DEBUG_KERNEL
760 ---help---
761 Enable to debug paravirt_ops internals. Specifically, BUG if
762 a paravirt_op is missing when it is called.
763
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700764config PARAVIRT_SPINLOCKS
765 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700766 depends on PARAVIRT && SMP
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700767 ---help---
768 Paravirtualized spinlocks allow a pvops backend to replace the
769 spinlock implementation with something virtualization-friendly
770 (for example, block the virtual CPU rather than spinning).
771
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530772 It has a minimal impact on native kernels and gives a nice performance
773 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700774
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530775 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700776
Waiman Long45e898b2015-11-09 19:09:25 -0500777config QUEUED_LOCK_STAT
778 bool "Paravirt queued spinlock statistics"
Peter Zijlstracfd89832016-05-18 20:43:02 +0200779 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
Waiman Long45e898b2015-11-09 19:09:25 -0500780 ---help---
781 Enable the collection of statistical data on the slowpath
782 behavior of paravirtualized queued spinlocks and report
783 them on debugfs.
784
Borislav Petkov6276a072013-03-04 21:20:21 +0100785source "arch/x86/xen/Kconfig"
786
787config KVM_GUEST
788 bool "KVM Guest support (including kvmclock)"
789 depends on PARAVIRT
790 select PARAVIRT_CLOCK
791 default y
792 ---help---
793 This option enables various optimizations for running under the KVM
794 hypervisor. It includes a paravirtualized clock, so that instead
795 of relying on a PIT (or probably other) emulation by the
796 underlying device model, the host provides the guest with
797 timing infrastructure such as time of day, and system time
798
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530799config KVM_DEBUG_FS
800 bool "Enable debug information for KVM Guests in debugfs"
801 depends on KVM_GUEST && DEBUG_FS
802 default n
803 ---help---
804 This option enables collection of various statistics for KVM guest.
805 Statistics are displayed in debugfs filesystem. Enabling this option
806 may incur significant overhead.
807
Borislav Petkov6276a072013-03-04 21:20:21 +0100808config PARAVIRT_TIME_ACCOUNTING
809 bool "Paravirtual steal time accounting"
810 depends on PARAVIRT
811 default n
812 ---help---
813 Select this option to enable fine granularity task steal time
814 accounting. Time spent executing other tasks in parallel with
815 the current vCPU is discounted from the vCPU power. To account for
816 that, there can be a small performance impact.
817
818 If in doubt, say N here.
819
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200820config PARAVIRT_CLOCK
821 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200822
Jan Kiszka4a362602017-11-27 09:11:46 +0100823config JAILHOUSE_GUEST
824 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100825 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100826 select X86_PM_TIMER
Jan Kiszka4a362602017-11-27 09:11:46 +0100827 ---help---
828 This option allows to run Linux as guest in a Jailhouse non-root
829 cell. You can leave this option disabled if you only want to start
830 Jailhouse and run Linux afterwards in the root cell.
831
Borislav Petkov6276a072013-03-04 21:20:21 +0100832endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400833
Yinghai Lu08677212010-02-10 01:20:20 -0800834config NO_BOOTMEM
Yinghai Lu774ea0b2010-08-25 13:39:18 -0700835 def_bool y
Yinghai Lu08677212010-02-10 01:20:20 -0800836
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100837source "arch/x86/Kconfig.cpu"
838
839config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100840 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100841 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100842 ---help---
843 Use the IA-PC HPET (High Precision Event Timer) to manage
844 time in preference to the PIT and RTC, if a HPET is
845 present.
846 HPET is the next generation timer replacing legacy 8254s.
847 The HPET provides a stable time base on SMP
848 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200849 as it is off-chip. The interface used is documented
850 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100851
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100852 You can safely choose Y here. However, HPET will only be
853 activated if the platform and the BIOS support this feature.
854 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100855
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100856 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100857
858config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100859 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800860 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100861
Jacob Panbb24c472009-09-02 07:37:17 -0700862config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000863 def_bool y if X86_INTEL_MID
864 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100865 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000866 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700867 help
868 APB timer is the replacement for 8254, HPET on X86 MID platforms.
869 The APBT provides a stable time base on SMP
870 systems, unlike the TSC, but it is more expensive to access,
871 as it is off-chip. APB timers are always running regardless of CPU
872 C states, they are used as per CPU clockevent device when possible.
873
David Rientjes6a108a12011-01-20 14:44:16 -0800874# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100875# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700876config DMI
877 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800878 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800879 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100880 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700881 Enabled scanning of DMI to identify machine quirks. Say Y
882 here unless you have verified that your setup is not
883 affected by entries in the DMI blacklist. Required by PNP
884 BIOS code.
885
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100886config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700887 bool "Old AMD GART IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200888 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100889 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200890 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100891 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200892 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
893 GART based hardware IOMMUs.
894
895 The GART supports full DMA access for devices with 32-bit access
896 limitations, on systems with more than 3 GB. This is usually needed
897 for USB, sound, many IDE/SATA chipsets and some other devices.
898
899 Newer systems typically have a modern AMD IOMMU, supported via
900 the CONFIG_AMD_IOMMU=y config option.
901
902 In normal configurations this driver is only active when needed:
903 there's more than 3 GB of memory and the system contains a
904 32-bit limited device.
905
906 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100907
908config CALGARY_IOMMU
909 bool "IBM Calgary IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200910 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100911 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700912 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100913 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100914 Support for hardware IOMMUs in IBM's xSeries x366 and x460
915 systems. Needed to run systems with more than 3GB of memory
916 properly with 32-bit PCI devices that do not support DAC
917 (Double Address Cycle). Calgary also supports bus level
918 isolation, where all DMAs pass through the IOMMU. This
919 prevents them from going anywhere except their intended
920 destination. This catches hard-to-find kernel bugs and
921 mis-behaving drivers and devices that do not use the DMA-API
922 properly to set up their DMA buffers. The IOMMU can be
923 turned off at boot time with the iommu=off parameter.
924 Normally the kernel will make the right choice by itself.
925 If unsure, say Y.
926
927config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100928 def_bool y
929 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100930 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100931 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100932 Should Calgary be enabled by default? if you choose 'y', Calgary
933 will be used (if it exists). If you choose 'n', Calgary will not be
934 used even if it exists. If you choose 'n' and would like to use
935 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
936 If unsure, say Y.
937
Mike Travis1184dc22008-05-12 21:21:12 +0200938config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200939 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700940 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800941 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100942 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200943 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200944 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100945
Ingo Molnaraec64872018-02-10 12:36:29 +0100946#
947# The maximum number of CPUs supported:
948#
949# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
950# and which can be configured interactively in the
951# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
952#
953# The ranges are different on 32-bit and 64-bit kernels, depending on
954# hardware capabilities and scalability features of the kernel.
955#
956# ( If MAXSMP is enabled we just use the highest possible value and disable
957# interactive configuration. )
958#
959
960config NR_CPUS_RANGE_BEGIN
961 int
962 default NR_CPUS_RANGE_END if MAXSMP
963 default 1 if !SMP
964 default 2
965
966config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800967 int
968 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100969 default 64 if SMP && X86_BIGSMP
970 default 8 if SMP && !X86_BIGSMP
971 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800972
Ingo Molnaraec64872018-02-10 12:36:29 +0100973config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800974 int
975 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100976 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
977 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
978 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800979
Ingo Molnaraec64872018-02-10 12:36:29 +0100980config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800981 int
982 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100983 default 32 if X86_BIGSMP
984 default 8 if SMP
985 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800986
Ingo Molnaraec64872018-02-10 12:36:29 +0100987config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800988 int
989 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100990 default 8192 if MAXSMP
991 default 64 if SMP
992 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800993
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100994config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800995 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +0100996 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
997 default NR_CPUS_DEFAULT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100998 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100999 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -05001000 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +03001001 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001002 minimum value which makes sense is 2.
1003
Ingo Molnaraec64872018-02-10 12:36:29 +01001004 This is purely to save memory: each supported CPU adds about 8KB
1005 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001006
1007config SCHED_SMT
1008 bool "SMT (Hyperthreading) scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001009 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001010 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001011 SMT scheduler support improves the CPU scheduler's decision making
1012 when dealing with Intel Pentium 4 chips with HyperThreading at a
1013 cost of slightly increased overhead in some places. If unsure say
1014 N here.
1015
1016config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001017 def_bool y
1018 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001019 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001020 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001021 Multi-core scheduler support improves the CPU scheduler's decision
1022 making when dealing with multi-core CPU chips at a cost of slightly
1023 increased overhead in some places. If unsure say N here.
1024
Tim Chende966cf2016-11-29 10:43:27 -08001025config SCHED_MC_PRIO
1026 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001027 depends on SCHED_MC && CPU_SUP_INTEL
1028 select X86_INTEL_PSTATE
1029 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001030 default y
Tim Chen5e76b2a2016-11-22 12:23:55 -08001031 ---help---
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001032 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1033 core ordering determined at manufacturing time, which allows
1034 certain cores to reach higher turbo frequencies (when running
1035 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001036
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001037 Enabling this kernel feature teaches the scheduler about
1038 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1039 scheduler's CPU selection logic accordingly, so that higher
1040 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001041
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001042 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001043
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001044 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001045
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001046config UP_LATE_INIT
1047 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +01001048 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001049
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001050config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001051 bool "Local APIC support on uniprocessors" if !PCI_MSI
1052 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001053 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001054 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001055 A local APIC (Advanced Programmable Interrupt Controller) is an
1056 integrated interrupt controller in the CPU. If you have a single-CPU
1057 system which has a processor with a local APIC, you can say Y here to
1058 enable and use it. If you say Y here even though your machine doesn't
1059 have a local APIC, then the kernel will still run with no slowdown at
1060 all. The local APIC supports CPU-generated self-interrupts (timer,
1061 performance counters), and the NMI watchdog which detects hard
1062 lockups.
1063
1064config X86_UP_IOAPIC
1065 bool "IO-APIC support on uniprocessors"
1066 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001067 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001068 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1069 SMP-capable replacement for PC-style interrupt controllers. Most
1070 SMP systems and many recent uniprocessor systems have one.
1071
1072 If you have a single-CPU system with an IO-APIC, you can say Y here
1073 to use it. If you say Y here even though your machine doesn't have
1074 an IO-APIC, then the kernel will still run with no slowdown at all.
1075
1076config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001077 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001078 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001079 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001080 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001081
1082config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001083 def_bool y
1084 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001085
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001086config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1087 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001088 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001089 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001090 This option enables a workaround that fixes a source of
1091 spurious interrupts. This is recommended when threaded
1092 interrupt handling is used on systems where the generation of
1093 superfluous "boot interrupts" cannot be disabled.
1094
1095 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1096 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1097 kernel does during interrupt handling). On chipsets where this
1098 boot IRQ generation cannot be disabled, this workaround keeps
1099 the original IRQ line masked so that only the equivalent "boot
1100 IRQ" is delivered to the CPUs. The workaround also tells the
1101 kernel to set up the IRQ handler on the boot IRQ line. In this
1102 way only one interrupt is delivered to the kernel. Otherwise
1103 the spurious second interrupt may cause the kernel to bring
1104 down (vital) interrupt lines.
1105
1106 Only affects "broken" chipsets. Interrupt sharing may be
1107 increased on these systems.
1108
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001109config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001110 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001111 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001112 default y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001113 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +02001114 Machine Check support allows the processor to notify the
1115 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001116 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001117 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001118
Tony Luck5de97c92017-03-27 11:33:03 +02001119config X86_MCELOG_LEGACY
1120 bool "Support for deprecated /dev/mcelog character device"
1121 depends on X86_MCE
1122 ---help---
1123 Enable support for /dev/mcelog which is needed by the old mcelog
1124 userspace logging daemon. Consider switching to the new generation
1125 rasdaemon solution.
1126
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001127config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001128 def_bool y
1129 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001130 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001131 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001132 Additional support for intel specific MCE features such as
1133 the thermal monitor.
1134
1135config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001136 def_bool y
1137 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001138 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001139 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001140 Additional support for AMD specific MCE features such as
1141 the DRAM Error Threshold.
1142
Andi Kleen4efc0672009-04-28 19:07:31 +02001143config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001144 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001145 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001146 ---help---
1147 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001148 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001149 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001150
Andi Kleenb2762682009-02-12 13:49:31 +01001151config X86_MCE_THRESHOLD
1152 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001153 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001154
Andi Kleenea149b32009-04-29 19:31:00 +02001155config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001156 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001157 tristate "Machine check injector support"
1158 ---help---
1159 Provide support for injecting machine checks for testing purposes.
1160 If you don't know what a machine check is and you don't do kernel
1161 QA it is safe to say n.
1162
Andi Kleen4efc0672009-04-28 19:07:31 +02001163config X86_THERMAL_VECTOR
1164 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001165 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001166
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001167source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001168
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001169config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001170 bool "Legacy VM86 support"
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001171 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001172 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001173 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001174 This option allows user programs to put the CPU into V8086
1175 mode, which is an 80286-era approximation of 16-bit real mode.
1176
1177 Some very old versions of X and/or vbetool require this option
1178 for user mode setting. Similarly, DOSEMU will use it if
1179 available to accelerate real mode DOS programs. However, any
1180 recent version of DOSEMU, X, or vbetool should be fully
1181 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001182 fall back to software emulation. Nevertheless, if you are using
1183 a 16-bit DOS program where 16-bit performance matters, vm86
1184 mode might be faster than emulation and you might want to
1185 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001186
Ingo Molnar1e642812015-09-05 08:58:10 +02001187 Note that any app that works on a 64-bit kernel is unlikely to
1188 need this option, as 64-bit kernels don't, and can't, support
1189 V8086 mode. This option is also unrelated to 16-bit protected
1190 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001191
Ingo Molnar1e642812015-09-05 08:58:10 +02001192 Enabling this option increases the complexity of the kernel
1193 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001194
Ingo Molnar1e642812015-09-05 08:58:10 +02001195 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001196
1197config VM86
1198 bool
1199 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001200
1201config X86_16BIT
1202 bool "Enable support for 16-bit segments" if EXPERT
1203 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001204 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001205 ---help---
1206 This option is required by programs like Wine to run 16-bit
1207 protected mode legacy code on x86 processors. Disabling
1208 this option saves about 300 bytes on i386, or around 6K text
1209 plus 16K runtime memory on x86-64,
1210
1211config X86_ESPFIX32
1212 def_bool y
1213 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001214
H. Peter Anvin197725d2014-05-04 10:00:49 -07001215config X86_ESPFIX64
1216 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001217 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001218
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001219config X86_VSYSCALL_EMULATION
1220 bool "Enable vsyscall emulation" if EXPERT
1221 default y
1222 depends on X86_64
1223 ---help---
1224 This enables emulation of the legacy vsyscall page. Disabling
1225 it is roughly equivalent to booting with vsyscall=none, except
1226 that it will also disable the helpful warning if a program
1227 tries to use a vsyscall. With this option set to N, offending
1228 programs will just segfault, citing addresses of the form
1229 0xffffffffff600?00.
1230
1231 This option is required by many programs built before 2013, and
1232 care should be used even with newer programs if set to N.
1233
1234 Disabling this option saves about 7K of kernel size and
1235 possibly 4K of additional runtime pagetable memory.
1236
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001237config TOSHIBA
1238 tristate "Toshiba Laptop support"
1239 depends on X86_32
1240 ---help---
1241 This adds a driver to safely access the System Management Mode of
1242 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1243 not work on models with a Phoenix BIOS. The System Management Mode
1244 is used to set the BIOS and power saving options on Toshiba portables.
1245
1246 For information on utilities to make use of this driver see the
1247 Toshiba Linux utilities web site at:
1248 <http://www.buzzard.org.uk/toshiba/>.
1249
1250 Say Y if you intend to run this kernel on a Toshiba portable.
1251 Say N otherwise.
1252
1253config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001254 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001255 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001256 select SENSORS_DELL_SMM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001257 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001258 This option enables legacy /proc/i8k userspace interface in hwmon
1259 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1260 temperature and allows controlling fan speeds of Dell laptops via
1261 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1262 it reports also power and hotkey status. For fan speed control is
1263 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001264
Pali Rohár039ae582015-05-14 13:16:37 +02001265 Say Y if you intend to run this kernel on old Dell laptops or want to
1266 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001267 Say N otherwise.
1268
1269config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001270 bool "Enable X86 board specific fixups for reboot"
1271 depends on X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001272 ---help---
1273 This enables chipset and/or board specific fixups to be done
1274 in order to get reboot to work correctly. This is only needed on
1275 some combinations of hardware and BIOS. The symptom, for which
1276 this config is intended, is when reboot ends with a stalled/hung
1277 system.
1278
1279 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001280 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001281
1282 Say Y if you want to enable the fixup. Currently, it's safe to
1283 enable this option even if you don't need it.
1284 Say N otherwise.
1285
1286config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001287 bool "CPU microcode loading support"
1288 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001289 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001290 select FW_LOADER
1291 ---help---
1292 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001293 Intel and AMD processors. The Intel support is for the IA32 family,
1294 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1295 AMD support is for families 0x10 and later. You will obviously need
1296 the actual microcode binary data itself which is not shipped with
1297 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001298
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001299 The preferred method to load microcode from a detached initrd is described
Jaak Ristioja1897a962018-02-09 11:22:16 +02001300 in Documentation/x86/microcode.txt. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001301 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1302 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001303
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001304 In addition, you can build the microcode into the kernel. For that you
1305 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1306 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001307
Peter Oruba8d86f392008-07-28 18:44:21 +02001308config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001309 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001310 depends on MICROCODE
1311 default MICROCODE
1312 select FW_LOADER
1313 ---help---
1314 This options enables microcode patch loading support for Intel
1315 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001316
Alanb8989db2014-01-20 18:01:56 +00001317 For the current Intel microcode data package go to
1318 <https://downloadcenter.intel.com> and search for
1319 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001320
Peter Oruba80cc9f12008-07-28 18:44:22 +02001321config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001322 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001323 depends on MICROCODE
1324 select FW_LOADER
1325 ---help---
1326 If you select this option, microcode patch loading support for AMD
1327 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001328
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001329config MICROCODE_OLD_INTERFACE
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001330 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001331 depends on MICROCODE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001332
1333config X86_MSR
1334 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001335 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001336 This device gives privileged processes access to the x86
1337 Model-Specific Registers (MSRs). It is a character device with
1338 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1339 MSR accesses are directed to a specific CPU on multi-processor
1340 systems.
1341
1342config X86_CPUID
1343 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001344 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001345 This device gives processes access to the x86 CPUID instruction to
1346 be executed on a specific processor. It is a character device
1347 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1348 /dev/cpu/31/cpuid.
1349
1350choice
1351 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001352 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001353 depends on X86_32
1354
1355config NOHIGHMEM
1356 bool "off"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001357 ---help---
1358 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1359 However, the address space of 32-bit x86 processors is only 4
1360 Gigabytes large. That means that, if you have a large amount of
1361 physical memory, not all of it can be "permanently mapped" by the
1362 kernel. The physical memory that's not permanently mapped is called
1363 "high memory".
1364
1365 If you are compiling a kernel which will never run on a machine with
1366 more than 1 Gigabyte total physical RAM, answer "off" here (default
1367 choice and suitable for most users). This will result in a "3GB/1GB"
1368 split: 3GB are mapped so that each process sees a 3GB virtual memory
1369 space and the remaining part of the 4GB virtual memory space is used
1370 by the kernel to permanently map as much physical memory as
1371 possible.
1372
1373 If the machine has between 1 and 4 Gigabytes physical RAM, then
1374 answer "4GB" here.
1375
1376 If more than 4 Gigabytes is used then answer "64GB" here. This
1377 selection turns Intel PAE (Physical Address Extension) mode on.
1378 PAE implements 3-level paging on IA32 processors. PAE is fully
1379 supported by Linux, PAE mode is implemented on all recent Intel
1380 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1381 then the kernel will not boot on CPUs that don't support PAE!
1382
1383 The actual amount of total physical memory will either be
1384 auto detected or can be forced by using a kernel command line option
1385 such as "mem=256M". (Try "man bootparam" or see the documentation of
1386 your boot loader (lilo or loadlin) about how to pass options to the
1387 kernel at boot time.)
1388
1389 If unsure, say "off".
1390
1391config HIGHMEM4G
1392 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001393 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001394 Select this if you have a 32-bit processor and between 1 and 4
1395 gigabytes of physical RAM.
1396
1397config HIGHMEM64G
1398 bool "64GB"
Matthew Whitehead69b8d3f2018-02-15 11:54:55 -05001399 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001400 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001401 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001402 Select this if you have a 32-bit processor and more than 4
1403 gigabytes of physical RAM.
1404
1405endchoice
1406
1407choice
David Rientjes6a108a12011-01-20 14:44:16 -08001408 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001409 default VMSPLIT_3G
1410 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001411 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001412 Select the desired split between kernel and user memory.
1413
1414 If the address range available to the kernel is less than the
1415 physical memory installed, the remaining memory will be available
1416 as "high memory". Accessing high memory is a little more costly
1417 than low memory, as it needs to be mapped into the kernel first.
1418 Note that increasing the kernel address space limits the range
1419 available to user programs, making the address space there
1420 tighter. Selecting anything other than the default 3G/1G split
1421 will also likely make your kernel incompatible with binary-only
1422 kernel modules.
1423
1424 If you are not absolutely sure what you are doing, leave this
1425 option alone!
1426
1427 config VMSPLIT_3G
1428 bool "3G/1G user/kernel split"
1429 config VMSPLIT_3G_OPT
1430 depends on !X86_PAE
1431 bool "3G/1G user/kernel split (for full 1G low memory)"
1432 config VMSPLIT_2G
1433 bool "2G/2G user/kernel split"
1434 config VMSPLIT_2G_OPT
1435 depends on !X86_PAE
1436 bool "2G/2G user/kernel split (for full 2G low memory)"
1437 config VMSPLIT_1G
1438 bool "1G/3G user/kernel split"
1439endchoice
1440
1441config PAGE_OFFSET
1442 hex
1443 default 0xB0000000 if VMSPLIT_3G_OPT
1444 default 0x80000000 if VMSPLIT_2G
1445 default 0x78000000 if VMSPLIT_2G_OPT
1446 default 0x40000000 if VMSPLIT_1G
1447 default 0xC0000000
1448 depends on X86_32
1449
1450config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001451 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001452 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001453
1454config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001455 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001456 depends on X86_32 && !HIGHMEM4G
Christoph Hellwigd4a451d2018-04-03 16:24:20 +02001457 select PHYS_ADDR_T_64BIT
Christian Melki9d99c712015-10-05 17:31:33 +02001458 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001459 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001460 PAE is required for NX support, and furthermore enables
1461 larger swapspace support for non-overcommit purposes. It
1462 has the cost of more pagetable lookup overhead, and also
1463 consumes more pagetable space per process.
1464
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001465config X86_5LEVEL
1466 bool "Enable 5-level page tables support"
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001467 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001468 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001469 depends on X86_64
1470 ---help---
1471 5-level paging enables access to larger address space:
1472 upto 128 PiB of virtual address space and 4 PiB of
1473 physical address space.
1474
1475 It will be supported by future Intel CPUs.
1476
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001477 A kernel with the option enabled can be booted on machines that
1478 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001479
1480 See Documentation/x86/x86_64/5level-paging.txt for more
1481 information.
1482
1483 Say N if unsure.
1484
Ingo Molnar10971ab2015-03-05 08:18:23 +01001485config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001486 def_bool y
Levin, Alexander (Sasha Levin)4675ff02017-11-15 17:36:02 -08001487 depends on X86_64 && !DEBUG_PAGEALLOC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001488 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001489 Certain kernel features effectively disable kernel
1490 linear 1 GB mappings (even if the CPU otherwise
1491 supports them), so don't confuse the user by printing
1492 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001493
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001494config ARCH_HAS_MEM_ENCRYPT
1495 def_bool y
1496
1497config AMD_MEM_ENCRYPT
1498 bool "AMD Secure Memory Encryption (SME) support"
1499 depends on X86_64 && CPU_SUP_AMD
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +03001500 select DYNAMIC_PHYSICAL_MASK
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001501 ---help---
1502 Say yes to enable support for the encryption of system memory.
1503 This requires an AMD processor that supports Secure Memory
1504 Encryption (SME).
1505
1506config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1507 bool "Activate AMD Secure Memory Encryption (SME) by default"
1508 default y
1509 depends on AMD_MEM_ENCRYPT
1510 ---help---
1511 Say yes to have system memory encrypted by default if running on
1512 an AMD processor that supports Secure Memory Encryption (SME).
1513
1514 If set to Y, then the encryption of system memory can be
1515 deactivated with the mem_encrypt=off command line option.
1516
1517 If set to N, then the encryption of system memory can be
1518 activated with the mem_encrypt=on command line option.
1519
Tom Lendackyf88a68f2017-07-17 16:10:09 -05001520config ARCH_USE_MEMREMAP_PROT
1521 def_bool y
1522 depends on AMD_MEM_ENCRYPT
1523
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001524# Common NUMA Features
1525config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001526 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001527 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001528 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1529 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001530 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001531 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001532
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001533 The kernel will try to allocate memory used by a CPU on the
1534 local memory controller of the CPU and add some more
1535 NUMA awareness to the kernel.
1536
Ingo Molnarc280ea52008-11-08 13:29:45 +01001537 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001538 (or later), AMD Opteron, or EM64T NUMA.
1539
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001540 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001541 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001542
1543 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001544
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001545config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001546 def_bool y
1547 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001548 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001549 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001550 Enable AMD NUMA node topology detection. You should say Y here if
1551 you have a multi processor AMD system. This uses an old method to
1552 read the NUMA configuration directly from the builtin Northbridge
1553 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1554 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001555
1556config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001557 def_bool y
1558 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001559 depends on X86_64 && NUMA && ACPI && PCI
1560 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001561 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001562 Enable ACPI SRAT based node topology detection.
1563
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001564# Some NUMA nodes have memory ranges that span
1565# other nodes. Even though a pfn is valid and
1566# between a node's start and end pfns, it may not
1567# reside on that node. See memmap_init_zone()
1568# for details.
1569config NODES_SPAN_OTHER_NODES
1570 def_bool y
1571 depends on X86_64_ACPI_NUMA
1572
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001573config NUMA_EMU
1574 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001575 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001576 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001577 Enable NUMA emulation. A flat machine will be split
1578 into virtual nodes when booted with "numa=fake=N", where N is the
1579 number of nodes. This is only useful for debugging.
1580
1581config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001582 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001583 range 1 10
1584 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001585 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001586 default "3"
1587 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001588 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001589 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001590 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001591
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001592config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001593 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001594 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001595
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001596config ARCH_FLATMEM_ENABLE
1597 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001598 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001599
1600config ARCH_DISCONTIGMEM_ENABLE
1601 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001602 depends on NUMA && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001603
1604config ARCH_DISCONTIGMEM_DEFAULT
1605 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001606 depends on NUMA && X86_32
1607
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001608config ARCH_SPARSEMEM_ENABLE
1609 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001610 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001611 select SPARSEMEM_STATIC if X86_32
1612 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1613
Tejun Heo3b166512011-04-01 11:15:12 +02001614config ARCH_SPARSEMEM_DEFAULT
1615 def_bool y
1616 depends on X86_64
1617
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001618config ARCH_SELECT_MEMORY_MODEL
1619 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001620 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001621
1622config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001623 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001624 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001625 help
1626 This option enables a sysfs memory/probe interface for testing.
1627 See Documentation/memory-hotplug.txt for more information.
1628 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001629
Tejun Heo3b166512011-04-01 11:15:12 +02001630config ARCH_PROC_KCORE_TEXT
1631 def_bool y
1632 depends on X86_64 && PROC_KCORE
1633
Avi Kivitya29815a2010-01-10 16:28:09 +02001634config ILLEGAL_POINTER_VALUE
1635 hex
1636 default 0 if X86_32
1637 default 0xdead000000000000 if X86_64
1638
Dan Williams7a678322015-08-19 00:34:34 -04001639config X86_PMEM_LEGACY_DEVICE
1640 bool
1641
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001642config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001643 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001644 depends on PHYS_ADDR_T_64BIT
1645 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001646 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001647 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001648 help
1649 Treat memory marked using the non-standard e820 type of 12 as used
1650 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1651 The kernel will offer these regions to the 'pmem' driver so
1652 they can be used for persistent storage.
1653
1654 Say Y if unsure.
1655
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001656config HIGHPTE
1657 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001658 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001659 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001660 The VM uses one page table entry for each page of physical memory.
1661 For systems with a lot of RAM, this can be wasteful of precious
1662 low memory. Setting this option will put user-space page table
1663 entries in high memory.
1664
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001665config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001666 bool "Check for low memory corruption"
1667 ---help---
1668 Periodically check for memory corruption in low memory, which
1669 is suspected to be caused by BIOS. Even when enabled in the
1670 configuration, it is disabled at runtime. Enable it by
1671 setting "memory_corruption_check=1" on the kernel command
1672 line. By default it scans the low 64k of memory every 60
1673 seconds; see the memory_corruption_check_size and
1674 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001675 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001676
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001677 When enabled with the default parameters, this option has
1678 almost no overhead, as it reserves a relatively small amount
1679 of memory and scans it infrequently. It both detects corruption
1680 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001681
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001682 It is, however, intended as a diagnostic tool; if repeatable
1683 BIOS-originated corruption always affects the same memory,
1684 you can use memmap= to prevent the kernel from using that
1685 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001686
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001687config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001688 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001689 depends on X86_CHECK_BIOS_CORRUPTION
1690 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001691 ---help---
1692 Set whether the default state of memory_corruption_check is
1693 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001694
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001695config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001696 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1697 default 64
1698 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001699 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001700 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001701
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001702 The first page contains BIOS data structures that the kernel
1703 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001704
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001705 By default we reserve the first 64K of physical RAM, as a
1706 number of BIOSes are known to corrupt that memory range
1707 during events such as suspend/resume or monitor cable
1708 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001709
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001710 You can set this to 4 if you are absolutely sure that you
1711 trust the BIOS to get all its memory reservations and usages
1712 right. If you know your BIOS have problems beyond the
1713 default 64K area, you can set this to 640 to avoid using the
1714 entire low memory range.
1715
1716 If you have doubts about the BIOS (e.g. suspend/resume does
1717 not work or there's kernel crashes after certain hardware
1718 hotplug events) then you might want to enable
1719 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1720 typical corruption patterns.
1721
1722 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001723
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001724config MATH_EMULATION
1725 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001726 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001727 prompt "Math emulation" if X86_32
1728 ---help---
1729 Linux can emulate a math coprocessor (used for floating point
1730 operations) if you don't have one. 486DX and Pentium processors have
1731 a math coprocessor built in, 486SX and 386 do not, unless you added
1732 a 487DX or 387, respectively. (The messages during boot time can
1733 give you some hints here ["man dmesg"].) Everyone needs either a
1734 coprocessor or this emulation.
1735
1736 If you don't have a math coprocessor, you need to say Y here; if you
1737 say Y here even though you have a coprocessor, the coprocessor will
1738 be used nevertheless. (This behavior can be changed with the kernel
1739 command line option "no387", which comes handy if your coprocessor
1740 is broken. Try "man bootparam" or see the documentation of your boot
1741 loader (lilo or loadlin) about how to pass options to the kernel at
1742 boot time.) This means that it is a good idea to say Y here if you
1743 intend to use this kernel on different machines.
1744
1745 More information about the internals of the Linux math coprocessor
1746 emulation can be found in <file:arch/x86/math-emu/README>.
1747
1748 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1749 kernel, it won't hurt.
1750
1751config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001752 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001753 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001754 ---help---
1755 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1756 the Memory Type Range Registers (MTRRs) may be used to control
1757 processor access to memory ranges. This is most useful if you have
1758 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1759 allows bus write transfers to be combined into a larger transfer
1760 before bursting over the PCI/AGP bus. This can increase performance
1761 of image write operations 2.5 times or more. Saying Y here creates a
1762 /proc/mtrr file which may be used to manipulate your processor's
1763 MTRRs. Typically the X server should use this.
1764
1765 This code has a reasonably generic interface so that similar
1766 control registers on other processors can be easily supported
1767 as well:
1768
1769 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1770 Registers (ARRs) which provide a similar functionality to MTRRs. For
1771 these, the ARRs are used to emulate the MTRRs.
1772 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1773 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1774 write-combining. All of these processors are supported by this code
1775 and it makes sense to say Y here if you have one of them.
1776
1777 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1778 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1779 can lead to all sorts of problems, so it's good to say Y here.
1780
1781 You can safely say Y even if your machine doesn't have MTRRs, you'll
1782 just add about 9 KB to your kernel.
1783
Randy Dunlap7225e752008-07-26 17:54:22 -07001784 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001785
Yinghai Lu95ffa242008-04-29 03:52:33 -07001786config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001787 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001788 prompt "MTRR cleanup support"
1789 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001790 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001791 Convert MTRR layout from continuous to discrete, so X drivers can
1792 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001793
Thomas Gleixneraba37282008-07-15 14:48:48 +02001794 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001795 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001796 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001797
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001798 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001799
1800config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001801 int "MTRR cleanup enable value (0-1)"
1802 range 0 1
1803 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001804 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001805 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001806 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001807
Yinghai Lu12031a62008-05-02 02:40:22 -07001808config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1809 int "MTRR cleanup spare reg num (0-7)"
1810 range 0 7
1811 default "1"
1812 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001813 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001814 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001815 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001816
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001817config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001818 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001819 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001820 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001821 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001822 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001823
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001824 PATs are the modern equivalents of MTRRs and are much more
1825 flexible than MTRRs.
1826
1827 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001828 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001829
1830 If unsure, say Y.
1831
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001832config ARCH_USES_PG_UNCACHED
1833 def_bool y
1834 depends on X86_PAT
1835
H. Peter Anvin628c6242011-07-31 13:59:29 -07001836config ARCH_RANDOM
1837 def_bool y
1838 prompt "x86 architectural random number generator" if EXPERT
1839 ---help---
1840 Enable the x86 architectural RDRAND instruction
1841 (Intel Bull Mountain technology) to generate random numbers.
1842 If supported, this is a high bandwidth, cryptographically
1843 secure hardware random number generator.
1844
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001845config X86_SMAP
1846 def_bool y
1847 prompt "Supervisor Mode Access Prevention" if EXPERT
1848 ---help---
1849 Supervisor Mode Access Prevention (SMAP) is a security
1850 feature in newer Intel processors. There is a small
1851 performance cost if this enabled and turned on; there is
1852 also a small increase in the kernel size if this is enabled.
1853
1854 If unsure, say Y.
1855
Ricardo Neriaa35f892017-11-05 18:27:54 -08001856config X86_INTEL_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001857 def_bool y
Ricardo Neriaa35f892017-11-05 18:27:54 -08001858 depends on CPU_SUP_INTEL
1859 prompt "Intel User Mode Instruction Prevention" if EXPERT
1860 ---help---
1861 The User Mode Instruction Prevention (UMIP) is a security
1862 feature in newer Intel processors. If enabled, a general
Ricardo Neri796ebc82017-11-13 22:29:42 -08001863 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1864 or STR instructions are executed in user mode. These instructions
1865 unnecessarily expose information about the hardware state.
1866
1867 The vast majority of applications do not use these instructions.
1868 For the very few that do, software emulation is provided in
1869 specific cases in protected and virtual-8086 modes. Emulated
1870 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001871
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001872config X86_INTEL_MPX
1873 prompt "Intel MPX (Memory Protection Extensions)"
1874 def_bool n
Rik van Rieldf3735c2017-09-06 16:25:11 -07001875 # Note: only available in 64-bit mode due to VMA flags shortage
1876 depends on CPU_SUP_INTEL && X86_64
1877 select ARCH_USES_HIGH_VMA_FLAGS
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001878 ---help---
1879 MPX provides hardware features that can be used in
1880 conjunction with compiler-instrumented code to check
1881 memory references. It is designed to detect buffer
1882 overflow or underflow bugs.
1883
1884 This option enables running applications which are
1885 instrumented or otherwise use MPX. It does not use MPX
1886 itself inside the kernel or to protect the kernel
1887 against bad memory references.
1888
1889 Enabling this option will make the kernel larger:
1890 ~8k of kernel text and 36 bytes of data on a 64-bit
1891 defconfig. It adds a long to the 'mm_struct' which
1892 will increase the kernel memory overhead of each
1893 process and adds some branches to paths used during
1894 exec() and munmap().
1895
1896 For details, see Documentation/x86/intel_mpx.txt
1897
1898 If unsure, say N.
1899
Dave Hansen35e97792016-02-12 13:02:00 -08001900config X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001901 prompt "Intel Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001902 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001903 # Note: only available in 64-bit mode
Dave Hansen35e97792016-02-12 13:02:00 -08001904 depends on CPU_SUP_INTEL && X86_64
Ingo Molnar52c8e602016-11-15 10:15:03 +01001905 select ARCH_USES_HIGH_VMA_FLAGS
1906 select ARCH_HAS_PKEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001907 ---help---
1908 Memory Protection Keys provides a mechanism for enforcing
1909 page-based protections, but without requiring modification of the
1910 page tables when an application changes protection domains.
1911
1912 For details, see Documentation/x86/protection-keys.txt
1913
1914 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001915
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001916config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001917 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001918 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001919 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001920 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001921 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001922 This enables the kernel to use EFI runtime services that are
1923 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001924
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001925 This option is only useful on systems that have EFI firmware.
1926 In addition, you should use the latest ELILO loader available
1927 at <http://elilo.sourceforge.net> in order to take advantage
1928 of EFI runtime services. However, even with this option, the
1929 resultant kernel should continue to boot on existing non-EFI
1930 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001931
Matt Fleming291f3632011-12-12 21:27:52 +00001932config EFI_STUB
1933 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001934 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001935 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001936 ---help---
1937 This kernel feature allows a bzImage to be loaded directly
1938 by EFI firmware without the use of a bootloader.
1939
Roy Franz4172fe22013-09-22 15:45:25 -07001940 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001941
Matt Fleming7d453ee2014-01-10 18:52:06 +00001942config EFI_MIXED
1943 bool "EFI mixed-mode support"
1944 depends on EFI_STUB && X86_64
1945 ---help---
1946 Enabling this feature allows a 64-bit kernel to be booted
1947 on a 32-bit firmware, provided that your CPU supports 64-bit
1948 mode.
1949
1950 Note that it is not possible to boot a mixed-mode enabled
1951 kernel via the EFI boot stub - a bootloader that supports
1952 the EFI handover protocol must be used.
1953
1954 If unsure, say N.
1955
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001956config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001957 def_bool y
1958 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001959 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001960 This kernel feature is useful for number crunching applications
1961 that may need to compute untrusted bytecode during their
1962 execution. By using pipes or other transports made available to
1963 the process as file descriptors supporting the read/write
1964 syscalls, it's possible to isolate those applications in
1965 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001966 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001967 and the task is only allowed to execute a few safe syscalls
1968 defined by each seccomp mode.
1969
1970 If unsure, say Y. Only embedded should say N here.
1971
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001972source kernel/Kconfig.hz
1973
1974config KEXEC
1975 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001976 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001977 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001978 kexec is a system call that implements the ability to shutdown your
1979 current kernel, and to start another kernel. It is like a reboot
1980 but it is independent of the system firmware. And like a reboot
1981 you can start any kernel with it, not just Linux.
1982
1983 The name comes from the similarity to the exec system call.
1984
1985 It is an ongoing process to be certain the hardware in a machine
1986 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001987 initially work for you. As of this writing the exact hardware
1988 interface is strongly in flux, so no good recommendation can be
1989 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001990
Vivek Goyal74ca3172014-08-29 15:18:46 -07001991config KEXEC_FILE
1992 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07001993 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07001994 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07001995 depends on X86_64
1996 depends on CRYPTO=y
1997 depends on CRYPTO_SHA256=y
1998 ---help---
1999 This is new version of kexec system call. This system call is
2000 file based and takes file descriptors as system call argument
2001 for kernel and initramfs as opposed to list of segments as
2002 accepted by previous system call.
2003
AKASHI Takahirob799a092018-04-13 15:35:45 -07002004config ARCH_HAS_KEXEC_PURGATORY
2005 def_bool KEXEC_FILE
2006
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002007config KEXEC_VERIFY_SIG
2008 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07002009 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002010 ---help---
2011 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002012 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002013
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002014 In addition to that option, you need to enable signature
2015 verification for the corresponding kernel image type being
2016 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002017
2018config KEXEC_BZIMAGE_VERIFY_SIG
2019 bool "Enable bzImage signature verification support"
2020 depends on KEXEC_VERIFY_SIG
2021 depends on SIGNED_PE_FILE_VERIFICATION
2022 select SYSTEM_TRUSTED_KEYRING
2023 ---help---
2024 Enable bzImage signature verification support.
2025
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002026config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002027 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002028 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002029 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002030 Generate crash dump after being started by kexec.
2031 This should be normally only set in special crash dump kernels
2032 which are loaded in the main kernel with kexec-tools into
2033 a specially reserved region and then later executed after
2034 a crash by kdump/kexec. The crash dump kernel must be compiled
2035 to a memory address not used by the main kernel or BIOS using
2036 PHYSICAL_START, or it must be built as a relocatable image
2037 (CONFIG_RELOCATABLE=y).
2038 For more details see Documentation/kdump/kdump.txt
2039
Huang Ying3ab83522008-07-25 19:45:07 -07002040config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002041 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002042 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002043 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07002044 Jump between original kernel and kexeced kernel and invoke
2045 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002046
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002047config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002048 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002049 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002050 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002051 This gives the physical address where the kernel is loaded.
2052
2053 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2054 bzImage will decompress itself to above physical address and
2055 run from there. Otherwise, bzImage will run from the address where
2056 it has been loaded by the boot loader and will ignore above physical
2057 address.
2058
2059 In normal kdump cases one does not have to set/change this option
2060 as now bzImage can be compiled as a completely relocatable image
2061 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2062 address. This option is mainly useful for the folks who don't want
2063 to use a bzImage for capturing the crash dump and want to use a
2064 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2065 to be specifically compiled to run from a specific memory area
2066 (normally a reserved region) and this option comes handy.
2067
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002068 So if you are using bzImage for capturing the crash dump,
2069 leave the value here unchanged to 0x1000000 and set
2070 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2071 for capturing the crash dump change this value to start of
2072 the reserved region. In other words, it can be set based on
2073 the "X" value as specified in the "crashkernel=YM@XM"
2074 command line boot parameter passed to the panic-ed
2075 kernel. Please take a look at Documentation/kdump/kdump.txt
2076 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002077
2078 Usage of bzImage for capturing the crash dump is recommended as
2079 one does not have to build two kernels. Same kernel can be used
2080 as production kernel and capture kernel. Above option should have
2081 gone away after relocatable bzImage support is introduced. But it
2082 is present because there are users out there who continue to use
2083 vmlinux for dump capture. This option should go away down the
2084 line.
2085
2086 Don't change this unless you know what you are doing.
2087
2088config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002089 bool "Build a relocatable kernel"
2090 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002091 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002092 This builds a kernel image that retains relocation information
2093 so it can be loaded someplace besides the default 1MB.
2094 The relocations tend to make the kernel binary about 10% larger,
2095 but are discarded at runtime.
2096
2097 One use is for the kexec on panic case where the recovery kernel
2098 must live at a different physical address than the primary
2099 kernel.
2100
2101 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2102 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002103 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002104
Kees Cook8ab38202013-10-10 17:18:14 -07002105config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002106 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002107 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002108 default y
Kees Cook8ab38202013-10-10 17:18:14 -07002109 ---help---
Baoquan Hee8581e32016-04-20 13:55:43 -07002110 In support of Kernel Address Space Layout Randomization (KASLR),
2111 this randomizes the physical address at which the kernel image
2112 is decompressed and the virtual address where the kernel
2113 image is mapped, as a security feature that deters exploit
2114 attempts relying on knowledge of the location of kernel
2115 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002116
Kees Cooked9f0072016-05-25 15:45:33 -07002117 On 64-bit, the kernel physical and virtual addresses are
2118 randomized separately. The physical address will be anywhere
2119 between 16MB and the top of physical memory (up to 64TB). The
2120 virtual address will be randomized from 16MB up to 1GB (9 bits
2121 of entropy). Note that this also reduces the memory space
2122 available to kernel modules from 1.5GB to 1GB.
2123
2124 On 32-bit, the kernel physical and virtual addresses are
2125 randomized together. They will be randomized from 16MB up to
2126 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002127
Baoquan Hee8581e32016-04-20 13:55:43 -07002128 Entropy is generated using the RDRAND instruction if it is
2129 supported. If RDTSC is supported, its value is mixed into
2130 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002131 supported, then entropy is read from the i8254 timer. The
2132 usable entropy is limited by the kernel being built using
2133 2GB addressing, and that PHYSICAL_ALIGN must be at a
2134 minimum of 2MB. As a result, only 10 bits of entropy are
2135 theoretically possible, but the implementations are further
2136 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002137
Ingo Molnar6807c842017-04-18 11:08:12 +02002138 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002139
2140# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002141config X86_NEED_RELOCS
2142 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002143 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002144
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002145config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002146 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002147 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002148 range 0x2000 0x1000000 if X86_32
2149 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002150 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002151 This value puts the alignment restrictions on physical address
2152 where kernel is loaded and run from. Kernel is compiled for an
2153 address which meets above alignment restriction.
2154
2155 If bootloader loads the kernel at a non-aligned address and
2156 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2157 address aligned to above value and run from there.
2158
2159 If bootloader loads the kernel at a non-aligned address and
2160 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2161 load address and decompress itself to the address it has been
2162 compiled for and run from there. The address for which kernel is
2163 compiled already meets above alignment restrictions. Hence the
2164 end result is that kernel runs from a physical address meeting
2165 above alignment restrictions.
2166
Kees Cooka0215062013-07-08 09:15:17 -07002167 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2168 this value must be a multiple of 0x200000.
2169
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002170 Don't change this unless you know what you are doing.
2171
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002172config DYNAMIC_MEMORY_LAYOUT
2173 bool
2174 ---help---
2175 This option makes base addresses of vmalloc and vmemmap as well as
2176 __PAGE_OFFSET movable during boot.
2177
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002178config RANDOMIZE_MEMORY
2179 bool "Randomize the kernel memory sections"
2180 depends on X86_64
2181 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002182 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002183 default RANDOMIZE_BASE
2184 ---help---
2185 Randomizes the base virtual address of kernel memory sections
2186 (physical memory mapping, vmalloc & vmemmap). This security feature
2187 makes exploits relying on predictable memory locations less reliable.
2188
2189 The order of allocations remains unchanged. Entropy is generated in
2190 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2191 configuration have in average 30,000 different possible virtual
2192 addresses for each memory section.
2193
Ingo Molnar6807c842017-04-18 11:08:12 +02002194 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002195
Thomas Garnier90397a42016-06-21 17:47:06 -07002196config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2197 hex "Physical memory mapping padding" if EXPERT
2198 depends on RANDOMIZE_MEMORY
2199 default "0xa" if MEMORY_HOTPLUG
2200 default "0x0"
2201 range 0x1 0x40 if MEMORY_HOTPLUG
2202 range 0x0 0x40
2203 ---help---
2204 Define the padding in terabytes added to the existing physical
2205 memory size during kernel memory randomization. It is useful
2206 for memory hotplug support but reduces the entropy available for
2207 address randomization.
2208
2209 If unsure, leave at the default value.
2210
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002211config HOTPLUG_CPU
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002212 bool "Support for hot-pluggable CPUs"
Stephen Rothwell40b31362013-05-21 13:49:35 +10002213 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002214 ---help---
Dimitri Sivanich7c13e6a2008-08-11 10:46:46 -05002215 Say Y here to allow turning CPUs off and on. CPUs can be
2216 controlled through /sys/devices/system/cpu.
2217 ( Note: power management support will enable this option
2218 automatically on SMP systems. )
2219 Say N if you want to disable CPU hotplug.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002220
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002221config BOOTPARAM_HOTPLUG_CPU0
2222 bool "Set default setting of cpu0_hotpluggable"
2223 default n
Kees Cook2c922cd2013-01-22 13:01:19 -08002224 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002225 ---help---
2226 Set whether default state of cpu0_hotpluggable is on or off.
2227
2228 Say Y here to enable CPU0 hotplug by default. If this switch
2229 is turned on, there is no need to give cpu0_hotplug kernel
2230 parameter and the CPU0 hotplug feature is enabled by default.
2231
2232 Please note: there are two known CPU0 dependencies if you want
2233 to enable the CPU0 hotplug feature either by this switch or by
2234 cpu0_hotplug kernel parameter.
2235
2236 First, resume from hibernate or suspend always starts from CPU0.
2237 So hibernate and suspend are prevented if CPU0 is offline.
2238
2239 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2240 offline if any interrupt can not migrate out of CPU0. There may
2241 be other CPU0 dependencies.
2242
2243 Please make sure the dependencies are under your control before
2244 you enable this feature.
2245
2246 Say N if you don't want to enable CPU0 hotplug feature by default.
2247 You still can enable the CPU0 hotplug feature at boot by kernel
2248 parameter cpu0_hotplug.
2249
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002250config DEBUG_HOTPLUG_CPU0
2251 def_bool n
2252 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002253 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002254 ---help---
2255 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2256 soon as possible and boots up userspace with CPU0 offlined. User
2257 can online CPU0 back after boot time.
2258
2259 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2260 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2261 compilation or giving cpu0_hotplug kernel parameter at boot.
2262
2263 If unsure, say N.
2264
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002265config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002266 def_bool n
2267 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002268 depends on COMPAT_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002269 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002270 Certain buggy versions of glibc will crash if they are
2271 presented with a 32-bit vDSO that is not mapped at the address
2272 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002273
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002274 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2275 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2276 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2277 the only released version with the bug, but OpenSUSE 9
2278 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002279
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002280 The symptom of the bug is that everything crashes on startup, saying:
2281 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2282
2283 Saying Y here changes the default value of the vdso32 boot
2284 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2285 This works around the glibc bug but hurts performance.
2286
2287 If unsure, say N: if you are compiling your own kernel, you
2288 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002289
Kees Cook3dc33bd2015-08-12 17:55:19 -07002290choice
2291 prompt "vsyscall table for legacy applications"
2292 depends on X86_64
2293 default LEGACY_VSYSCALL_EMULATE
2294 help
2295 Legacy user code that does not know how to find the vDSO expects
2296 to be able to issue three syscalls by calling fixed addresses in
2297 kernel space. Since this location is not randomized with ASLR,
2298 it can be used to assist security vulnerability exploitation.
2299
2300 This setting can be changed at boot time via the kernel command
Andy Lutomirski076ca272018-03-07 11:12:27 -08002301 line parameter vsyscall=[emulate|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002302
2303 On a system with recent enough glibc (2.14 or newer) and no
2304 static binaries, you can say None without a performance penalty
2305 to improve security.
2306
2307 If unsure, select "Emulate".
2308
Kees Cook3dc33bd2015-08-12 17:55:19 -07002309 config LEGACY_VSYSCALL_EMULATE
2310 bool "Emulate"
2311 help
2312 The kernel traps and emulates calls into the fixed
2313 vsyscall address mapping. This makes the mapping
2314 non-executable, but it still contains known contents,
2315 which could be used in certain rare security vulnerability
2316 exploits. This configuration is recommended when userspace
2317 still uses the vsyscall area.
2318
2319 config LEGACY_VSYSCALL_NONE
2320 bool "None"
2321 help
2322 There will be no vsyscall mapping at all. This will
2323 eliminate any risk of ASLR bypass due to the vsyscall
2324 fixed address mapping. Attempts to use the vsyscalls
2325 will be reported to dmesg, so that either old or
2326 malicious userspace programs can be identified.
2327
2328endchoice
2329
Tim Bird516cbf32008-08-12 12:52:36 -07002330config CMDLINE_BOOL
2331 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002332 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002333 Allow for specifying boot arguments to the kernel at
2334 build time. On some systems (e.g. embedded ones), it is
2335 necessary or convenient to provide some or all of the
2336 kernel boot arguments with the kernel itself (that is,
2337 to not rely on the boot loader to provide them.)
2338
2339 To compile command line arguments into the kernel,
2340 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002341 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002342
2343 Systems with fully functional boot loaders (i.e. non-embedded)
2344 should leave this option set to 'N'.
2345
2346config CMDLINE
2347 string "Built-in kernel command string"
2348 depends on CMDLINE_BOOL
2349 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002350 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002351 Enter arguments here that should be compiled into the kernel
2352 image and used at boot time. If the boot loader provides a
2353 command line at boot time, it is appended to this string to
2354 form the full kernel command line, when the system boots.
2355
2356 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2357 change this behavior.
2358
2359 In most cases, the command line (whether built-in or provided
2360 by the boot loader) should specify the device for the root
2361 file system.
2362
2363config CMDLINE_OVERRIDE
2364 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002365 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002366 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002367 Set this option to 'Y' to have the kernel ignore the boot loader
2368 command line, and use ONLY the built-in command line.
2369
2370 This is used to work around broken boot loaders. This should
2371 be set to 'N' under normal conditions.
2372
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002373config MODIFY_LDT_SYSCALL
2374 bool "Enable the LDT (local descriptor table)" if EXPERT
2375 default y
2376 ---help---
2377 Linux can allow user programs to install a per-process x86
2378 Local Descriptor Table (LDT) using the modify_ldt(2) system
2379 call. This is required to run 16-bit or segmented code such as
2380 DOSEMU or some Wine programs. It is also used by some very old
2381 threading libraries.
2382
2383 Enabling this feature adds a small amount of overhead to
2384 context switches and increases the low-level kernel attack
2385 surface. Disabling it removes the modify_ldt(2) system call.
2386
2387 Saying 'N' here may make sense for embedded or server kernels.
2388
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002389source "kernel/livepatch/Kconfig"
2390
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002391endmenu
2392
Michal Hocko3072e412017-09-08 16:11:39 -07002393config ARCH_HAS_ADD_PAGES
2394 def_bool y
2395 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2396
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002397config ARCH_ENABLE_MEMORY_HOTPLUG
2398 def_bool y
2399 depends on X86_64 || (X86_32 && HIGHMEM)
2400
Gary Hade35551052008-10-31 10:52:03 -07002401config ARCH_ENABLE_MEMORY_HOTREMOVE
2402 def_bool y
2403 depends on MEMORY_HOTPLUG
2404
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002405config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002406 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002407 depends on NUMA
2408
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002409config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2410 def_bool y
2411 depends on X86_64 || X86_PAE
2412
Naoya Horiguchic177c812014-06-04 16:05:35 -07002413config ARCH_ENABLE_HUGEPAGE_MIGRATION
2414 def_bool y
2415 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2416
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002417config ARCH_ENABLE_THP_MIGRATION
2418 def_bool y
2419 depends on X86_64 && TRANSPARENT_HUGEPAGE
2420
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002421menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002422
2423config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002424 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002425 depends on X86_64 && HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002426
2427source "kernel/power/Kconfig"
2428
2429source "drivers/acpi/Kconfig"
2430
Feng Tangefafc8b2009-08-14 15:23:29 -04002431source "drivers/sfi/Kconfig"
2432
Andi Kleena6b68072008-01-30 13:32:49 +01002433config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002434 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002435 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002436
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002437menuconfig APM
2438 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002439 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002440 ---help---
2441 APM is a BIOS specification for saving power using several different
2442 techniques. This is mostly useful for battery powered laptops with
2443 APM compliant BIOSes. If you say Y here, the system time will be
2444 reset after a RESUME operation, the /proc/apm device will provide
2445 battery status information, and user-space programs will receive
2446 notification of APM "events" (e.g. battery status change).
2447
2448 If you select "Y" here, you can disable actual use of the APM
2449 BIOS by passing the "apm=off" option to the kernel at boot time.
2450
2451 Note that the APM support is almost completely disabled for
2452 machines with more than one CPU.
2453
2454 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002455 and more information, read <file:Documentation/power/apm-acpi.txt>
2456 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002457 <http://www.tldp.org/docs.html#howto>.
2458
2459 This driver does not spin down disk drives (see the hdparm(8)
2460 manpage ("man 8 hdparm") for that), and it doesn't turn off
2461 VESA-compliant "green" monitors.
2462
2463 This driver does not support the TI 4000M TravelMate and the ACER
2464 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2465 desktop machines also don't have compliant BIOSes, and this driver
2466 may cause those machines to panic during the boot phase.
2467
2468 Generally, if you don't have a battery in your machine, there isn't
2469 much point in using this driver and you should say N. If you get
2470 random kernel OOPSes or reboots that don't seem to be related to
2471 anything, try disabling/enabling this option (or disabling/enabling
2472 APM in your BIOS).
2473
2474 Some other things you should try when experiencing seemingly random,
2475 "weird" problems:
2476
2477 1) make sure that you have enough swap space and that it is
2478 enabled.
2479 2) pass the "no-hlt" option to the kernel
2480 3) switch on floating point emulation in the kernel and pass
2481 the "no387" option to the kernel
2482 4) pass the "floppy=nodma" option to the kernel
2483 5) pass the "mem=4M" option to the kernel (thereby disabling
2484 all but the first 4 MB of RAM)
2485 6) make sure that the CPU is not over clocked.
2486 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2487 8) disable the cache from your BIOS settings
2488 9) install a fan for the video card or exchange video RAM
2489 10) install a better fan for the CPU
2490 11) exchange RAM chips
2491 12) exchange the motherboard.
2492
2493 To compile this driver as a module, choose M here: the
2494 module will be called apm.
2495
2496if APM
2497
2498config APM_IGNORE_USER_SUSPEND
2499 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002500 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002501 This option will ignore USER SUSPEND requests. On machines with a
2502 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2503 series notebooks, it is necessary to say Y because of a BIOS bug.
2504
2505config APM_DO_ENABLE
2506 bool "Enable PM at boot time"
2507 ---help---
2508 Enable APM features at boot time. From page 36 of the APM BIOS
2509 specification: "When disabled, the APM BIOS does not automatically
2510 power manage devices, enter the Standby State, enter the Suspend
2511 State, or take power saving steps in response to CPU Idle calls."
2512 This driver will make CPU Idle calls when Linux is idle (unless this
2513 feature is turned off -- see "Do CPU IDLE calls", below). This
2514 should always save battery power, but more complicated APM features
2515 will be dependent on your BIOS implementation. You may need to turn
2516 this option off if your computer hangs at boot time when using APM
2517 support, or if it beeps continuously instead of suspending. Turn
2518 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2519 T400CDT. This is off by default since most machines do fine without
2520 this feature.
2521
2522config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002523 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002524 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002525 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002526 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2527 On some machines, this can activate improved power savings, such as
2528 a slowed CPU clock rate, when the machine is idle. These idle calls
2529 are made after the idle loop has run for some length of time (e.g.,
2530 333 mS). On some machines, this will cause a hang at boot time or
2531 whenever the CPU becomes idle. (On machines with more than one CPU,
2532 this option does nothing.)
2533
2534config APM_DISPLAY_BLANK
2535 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002536 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002537 Enable console blanking using the APM. Some laptops can use this to
2538 turn off the LCD backlight when the screen blanker of the Linux
2539 virtual console blanks the screen. Note that this is only used by
2540 the virtual console screen blanker, and won't turn off the backlight
2541 when using the X Window system. This also doesn't have anything to
2542 do with your VESA-compliant power-saving monitor. Further, this
2543 option doesn't work for all laptops -- it might not turn off your
2544 backlight at all, or it might print a lot of errors to the console,
2545 especially if you are using gpm.
2546
2547config APM_ALLOW_INTS
2548 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002549 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002550 Normally we disable external interrupts while we are making calls to
2551 the APM BIOS as a measure to lessen the effects of a badly behaving
2552 BIOS implementation. The BIOS should reenable interrupts if it
2553 needs to. Unfortunately, some BIOSes do not -- especially those in
2554 many of the newer IBM Thinkpads. If you experience hangs when you
2555 suspend, try setting this to Y. Otherwise, say N.
2556
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002557endif # APM
2558
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002559source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002560
2561source "drivers/cpuidle/Kconfig"
2562
Andy Henroid27471fd2008-10-09 11:45:22 -07002563source "drivers/idle/Kconfig"
2564
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002565endmenu
2566
2567
2568menu "Bus options (PCI etc.)"
2569
2570config PCI
Ingo Molnar1ac97012008-05-19 14:10:14 +02002571 bool "PCI support"
Adrian Bunk1c858082008-01-30 13:32:32 +01002572 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002573 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002574 Find out whether you have a PCI motherboard. PCI is the name of a
2575 bus system, i.e. the way the CPU talks to the other stuff inside
2576 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2577 VESA. If you have PCI, say Y, otherwise N.
2578
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002579choice
2580 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002581 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002582 default PCI_GOANY
2583 ---help---
2584 On PCI systems, the BIOS can be used to detect the PCI devices and
2585 determine their configuration. However, some old PCI motherboards
2586 have BIOS bugs and may crash if this is done. Also, some embedded
2587 PCI-based systems don't have any BIOS at all. Linux can also try to
2588 detect the PCI hardware directly without using the BIOS.
2589
2590 With this option, you can specify how Linux should detect the
2591 PCI devices. If you choose "BIOS", the BIOS will be used,
2592 if you choose "Direct", the BIOS won't be used, and if you
2593 choose "MMConfig", then PCI Express MMCONFIG will be used.
2594 If you choose "Any", the kernel will try MMCONFIG, then the
2595 direct access method and falls back to the BIOS if that doesn't
2596 work. If unsure, go with the default, which is "Any".
2597
2598config PCI_GOBIOS
2599 bool "BIOS"
2600
2601config PCI_GOMMCONFIG
2602 bool "MMConfig"
2603
2604config PCI_GODIRECT
2605 bool "Direct"
2606
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002607config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002608 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002609 depends on OLPC
2610
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002611config PCI_GOANY
2612 bool "Any"
2613
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002614endchoice
2615
2616config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002617 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002618 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002619
2620# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2621config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002622 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002623 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002624
2625config PCI_MMCONFIG
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002626 bool "Support mmconfig PCI config space access" if X86_64
2627 default y
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002628 depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002629 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002630
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002631config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002632 def_bool y
2633 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002634
Alex Nixonb5401a92010-03-18 16:31:34 -04002635config PCI_XEN
2636 def_bool y
2637 depends on PCI && XEN
2638 select SWIOTLB_XEN
2639
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002640config PCI_DOMAINS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002641 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002642 depends on PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002643
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002644config MMCONF_FAM10H
2645 def_bool y
2646 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002647
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002648config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002649 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002650 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002651 help
2652 Read the PCI windows out of the CNB20LE host bridge. This allows
2653 PCI hotplug to work on systems with the CNB20LE chipset which do
2654 not have ACPI.
2655
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002656 There's no public spec for this chipset, and this functionality
2657 is known to be incomplete.
2658
2659 You should say N unless you know you need this.
2660
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002661source "drivers/pci/Kconfig"
2662
William Breathitt Gray3a495512016-05-27 18:08:27 -04002663config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002664 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002665 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002666 Expose ISA bus device drivers and options available for selection and
2667 configuration. Enable this option if your target machine has an ISA
2668 bus. ISA is an older system, displaced by PCI and newer bus
2669 architectures -- if your target machine is modern, it probably does
2670 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002671
2672 If unsure, say N.
2673
David Rientjes1c00f012011-03-22 16:34:59 -07002674# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002675config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002676 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2677 default y
2678 help
2679 Enables ISA-style DMA support for devices requiring such controllers.
2680 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002681
Linus Torvalds51e68d02016-05-21 10:25:19 -07002682if X86_32
2683
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002684config ISA
2685 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002686 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002687 Find out whether you have ISA slots on your motherboard. ISA is the
2688 name of a bus system, i.e. the way the CPU talks to the other stuff
2689 inside your box. Other bus systems are PCI, EISA, MicroChannel
2690 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2691 newer boards don't support it. If you have ISA, say Y, otherwise N.
2692
2693config EISA
2694 bool "EISA support"
2695 depends on ISA
2696 ---help---
2697 The Extended Industry Standard Architecture (EISA) bus was
2698 developed as an open alternative to the IBM MicroChannel bus.
2699
2700 The EISA bus provided some of the features of the IBM MicroChannel
2701 bus while maintaining backward compatibility with cards made for
2702 the older ISA bus. The EISA bus saw limited use between 1988 and
2703 1995 when it was made obsolete by the PCI bus.
2704
2705 Say Y here if you are building a kernel for an EISA-based machine.
2706
2707 Otherwise, say N.
2708
2709source "drivers/eisa/Kconfig"
2710
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002711config SCx200
2712 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002713 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002714 This provides basic support for National Semiconductor's
2715 (now AMD's) Geode processors. The driver probes for the
2716 PCI-IDs of several on-chip devices, so its a good dependency
2717 for other scx200_* drivers.
2718
2719 If compiled as a module, the driver is named scx200.
2720
2721config SCx200HR_TIMER
2722 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002723 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002724 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002725 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002726 This driver provides a clocksource built upon the on-chip
2727 27MHz high-resolution timer. Its also a workaround for
2728 NSC Geode SC-1100's buggy TSC, which loses time when the
2729 processor goes idle (as is done by the scheduler). The
2730 other workaround is idle=poll boot option.
2731
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002732config OLPC
2733 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002734 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002735 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002736 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002737 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002738 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002739 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002740 Add support for detecting the unique features of the OLPC
2741 XO hardware.
2742
Daniel Drakea3128582011-06-25 17:34:10 +01002743config OLPC_XO1_PM
2744 bool "OLPC XO-1 Power Management"
Borislav Petkovfa112cf2018-10-05 15:13:07 +02002745 depends on OLPC && MFD_CS5535=y && PM_SLEEP
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002746 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002747 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002748
Daniel Drakecfee9592011-06-25 17:34:17 +01002749config OLPC_XO1_RTC
2750 bool "OLPC XO-1 Real Time Clock"
2751 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2752 ---help---
2753 Add support for the XO-1 real time clock, which can be used as a
2754 programmable wakeup source.
2755
Daniel Drake7feda8e2011-06-25 17:34:12 +01002756config OLPC_XO1_SCI
2757 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002758 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002759 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002760 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002761 ---help---
2762 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002763 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002764 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002765 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002766 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002767 - AC adapter status updates
2768 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002769
Daniel Drakea0f30f52011-06-25 17:34:18 +01002770config OLPC_XO15_SCI
2771 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002772 depends on OLPC && ACPI
2773 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002774 ---help---
2775 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2776 - EC-driven system wakeups
2777 - AC adapter status updates
2778 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002779
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002780config ALIX
2781 bool "PCEngines ALIX System Support (LED setup)"
2782 select GPIOLIB
2783 ---help---
2784 This option enables system support for the PCEngines ALIX.
2785 At present this just sets up LEDs for GPIO control on
2786 ALIX2/3/6 boards. However, other system specific setup should
2787 get added here.
2788
2789 Note: You must still enable the drivers for GPIO and LED support
2790 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2791
2792 Note: You have to set alix.force=1 for boards with Award BIOS.
2793
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002794config NET5501
2795 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2796 select GPIOLIB
2797 ---help---
2798 This option enables system support for the Soekris Engineering net5501.
2799
Philip A. Prindeville31970592012-01-14 01:45:39 -07002800config GEOS
2801 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2802 select GPIOLIB
2803 depends on DMI
2804 ---help---
2805 This option enables system support for the Traverse Technologies GEOS.
2806
Vivien Didelot7d029122013-01-04 16:18:14 -05002807config TS5500
2808 bool "Technologic Systems TS-5500 platform support"
2809 depends on MELAN
2810 select CHECK_SIGNATURE
2811 select NEW_LEDS
2812 select LEDS_CLASS
2813 ---help---
2814 This option enables system support for the Technologic Systems TS-5500.
2815
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002816endif # X86_32
2817
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002818config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002819 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002820 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002821
2822source "drivers/pcmcia/Kconfig"
2823
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002824config RAPIDIO
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002825 tristate "RapidIO support"
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002826 depends on PCI
2827 default n
2828 help
Alexandre Bouninefdf90ab2013-07-03 15:08:56 -07002829 If enabled this option will include drivers and the core
Alexandre Bounine388b78a2011-03-23 16:43:03 -07002830 infrastructure code to support RapidIO interconnect devices.
2831
2832source "drivers/rapidio/Kconfig"
2833
David Herrmanne3263ab2013-08-02 14:05:22 +02002834config X86_SYSFB
2835 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2836 help
2837 Firmwares often provide initial graphics framebuffers so the BIOS,
2838 bootloader or kernel can show basic video-output during boot for
2839 user-guidance and debugging. Historically, x86 used the VESA BIOS
2840 Extensions and EFI-framebuffers for this, which are mostly limited
2841 to x86.
2842 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2843 framebuffers so the new generic system-framebuffer drivers can be
2844 used on x86. If the framebuffer is not compatible with the generic
Nikolas Nybye3a5dc02018-08-25 19:10:54 -04002845 modes, it is advertised as fallback platform framebuffer so legacy
David Herrmanne3263ab2013-08-02 14:05:22 +02002846 drivers like efifb, vesafb and uvesafb can pick it up.
2847 If this option is not selected, all system framebuffers are always
2848 marked as fallback platform framebuffers as usual.
2849
2850 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2851 not be able to pick up generic system framebuffers if this option
2852 is selected. You are highly encouraged to enable simplefb as
2853 replacement if you select this option. simplefb can correctly deal
2854 with generic system framebuffers. But you should still keep vesafb
2855 and others enabled as fallback if a system framebuffer is
2856 incompatible with simplefb.
2857
2858 If unsure, say Y.
2859
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002860endmenu
2861
2862
Christoph Hellwig15724972018-07-31 13:39:30 +02002863menu "Binary Emulations"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002864
2865config IA32_EMULATION
2866 bool "IA32 Emulation"
2867 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002868 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002869 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002870 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002871 select COMPAT_OLD_SIGACTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002872 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002873 Include code to run legacy 32-bit programs under a
2874 64-bit kernel. You should likely turn this on, unless you're
2875 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002876
2877config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002878 tristate "IA32 a.out support"
2879 depends on IA32_EMULATION
2880 ---help---
2881 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002882
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002883config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002884 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002885 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002886 ---help---
2887 Include code to run binaries for the x32 native 32-bit ABI
2888 for 64-bit processors. An x32 process gets access to the
2889 full 64-bit register file and wide data path while leaving
2890 pointers at 32 bits for smaller memory footprint.
2891
2892 You will need a recent binutils (2.22 or later) with
2893 elf32_x86_64 support enabled to compile a kernel with this
2894 option set.
2895
Ingo Molnar953fee12016-11-15 10:22:52 +01002896config COMPAT_32
2897 def_bool y
2898 depends on IA32_EMULATION || X86_32
2899 select HAVE_UID16
2900 select OLD_SIGSUSPEND3
2901
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002902config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002903 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002904 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002905
Jan Beulich3120e252012-09-10 12:41:45 +01002906if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002907config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002908 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002909
2910config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002911 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002912 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002913endif
David Howellsee009e4a02011-03-07 15:06:20 +00002914
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002915endmenu
2916
2917
Keith Packarde5beae12008-11-03 18:21:45 +01002918config HAVE_ATOMIC_IOMAP
2919 def_bool y
2920 depends on X86_32
2921
Alessandro Rubini4692d772012-04-04 19:39:58 +02002922config X86_DEV_DMA_OPS
2923 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002924 depends on X86_64 || STA2X11
Alessandro Rubini4692d772012-04-04 19:39:58 +02002925
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002926config X86_DMA_REMAP
2927 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002928 depends on STA2X11
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002929
Kirill A. Shutemove5855132017-06-06 14:31:20 +03002930config HAVE_GENERIC_GUP
2931 def_bool y
2932
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002933source "drivers/firmware/Kconfig"
2934
Avi Kivityedf88412007-12-16 11:02:48 +02002935source "arch/x86/kvm/Kconfig"