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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
Ingo Molnar341c7872016-11-15 10:04:55 +010017 select MODULES_USE_ELF_REL
18 select OLD_SIGACTION
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +010019
20config X86_64
Jan Beulich3120e252012-09-10 12:41:45 +010021 def_bool y
22 depends on 64BIT
Ingo Molnard94e0682016-11-15 10:11:57 +010023 # Options that are inherently 64-bit kernel only:
Aneesh Kumar K.Ve1073d12017-07-06 15:39:17 -070024 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
Ingo Molnard94e0682016-11-15 10:11:57 +010025 select ARCH_SUPPORTS_INT128
26 select ARCH_USE_CMPXCHG_LOCKREF
27 select HAVE_ARCH_SOFT_DIRTY
28 select MODULES_USE_ELF_RELA
Christoph Hellwigf616ab52018-05-09 06:53:49 +020029 select NEED_DMA_MAP_STATE
Christoph Hellwig09230cb2018-04-24 09:00:54 +020030 select SWIOTLB
Ingo Molnard94e0682016-11-15 10:11:57 +010031 select X86_DEV_DMA_OPS
Dominik Brodowskif8781c42018-04-05 11:53:05 +020032 select ARCH_HAS_SYSCALL_WRAPPER
Sam Ravnborg1032c0b2007-11-06 21:35:08 +010033
Ingo Molnard94e0682016-11-15 10:11:57 +010034#
35# Arch settings
36#
37# ( Note that options that are marked 'if X86_64' could in principle be
38# ported to 32-bit as well. )
39#
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +010040config X86
Harvey Harrison3c2362e2008-01-30 13:31:03 +010041 def_bool y
Ingo Molnarc763ea22016-11-15 10:26:39 +010042 #
43 # Note: keep this list sorted alphabetically
44 #
Ingo Molnar6471b822015-06-03 10:00:13 +020045 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
46 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
47 select ANON_INODES
Yury Norov942fa982018-05-16 11:18:49 +030048 select ARCH_32BIT_OFF_T if X86_32
Ingo Molnar6471b822015-06-03 10:00:13 +020049 select ARCH_CLOCKSOURCE_DATA
Thomas Gleixner2a21ad52018-09-17 14:45:35 +020050 select ARCH_CLOCKSOURCE_INIT
Ingo Molnar6471b822015-06-03 10:00:13 +020051 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
Laura Abbottad21fc42017-02-06 16:31:57 -080068 select ARCH_HAS_STRICT_KERNEL_RWX
69 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050070 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Andrey Ryabininc6d30852016-01-20 15:00:55 -080071 select ARCH_HAS_UBSAN_SANITIZE_ALL
Oliver O'Halloran65f7d042017-06-28 11:32:31 +100072 select ARCH_HAS_ZONE_DEVICE if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020073 select ARCH_HAVE_NMI_SAFE_CMPXCHG
74 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040075 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080076 select ARCH_MIGHT_HAVE_PC_SERIO
Arnd Bergmann2c870e62018-07-24 11:48:45 +020077 select ARCH_SUPPORTS_ACPI
Ingo Molnar6471b822015-06-03 10:00:13 +020078 select ARCH_SUPPORTS_ATOMIC_RMW
Ingo Molnar6471b822015-06-03 10:00:13 +020079 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
80 select ARCH_USE_BUILTIN_BSWAP
Ingo Molnar6471b822015-06-03 10:00:13 +020081 select ARCH_USE_QUEUED_RWLOCKS
82 select ARCH_USE_QUEUED_SPINLOCKS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -070083 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Ingo Molnarc763ea22016-11-15 10:26:39 +010084 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Huang Ying38d8b4e2017-07-06 15:37:18 -070085 select ARCH_WANTS_THP_SWAP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020086 select BUILDTIME_EXTABLE_SORT
87 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +020088 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
89 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +020090 select DCACHE_WORD_ACCESS
Linus Torvalds45471cd2015-06-24 19:52:06 -070091 select EDAC_ATOMIC_SCRUB
92 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +020093 select GENERIC_CLOCKEVENTS
94 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
95 select GENERIC_CLOCKEVENTS_MIN_ADJUST
96 select GENERIC_CMOS_UPDATE
97 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +010098 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +020099 select GENERIC_EARLY_IOREMAP
100 select GENERIC_FIND_FIRST_BIT
101 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +0200102 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +0200103 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +0200104 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200105 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200106 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200107 select GENERIC_IRQ_SHOW
108 select GENERIC_PENDING_IRQ if SMP
109 select GENERIC_SMP_IDLE_THREAD
110 select GENERIC_STRNCPY_FROM_USER
111 select GENERIC_STRNLEN_USER
112 select GENERIC_TIME_VSYSCALL
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200113 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200114 select HAVE_ACPI_APEI if ACPI
115 select HAVE_ACPI_APEI_NMI if ACPI
116 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200117 select HAVE_ARCH_AUDITSYSCALL
118 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
119 select HAVE_ARCH_JUMP_LABEL
Ard Biesheuvelb34006c2018-09-18 23:51:41 -0700120 select HAVE_ARCH_JUMP_LABEL_RELATIVE
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800121 select HAVE_ARCH_KASAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200122 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800123 select HAVE_ARCH_MMAP_RND_BITS if MMU
124 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300125 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ard Biesheuvel271ca782018-08-21 21:56:00 -0700126 select HAVE_ARCH_PREL32_RELOCATIONS
Ingo Molnar6471b822015-06-03 10:00:13 +0200127 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700128 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Alexander Popovafaef012018-08-17 01:16:58 +0300129 select HAVE_ARCH_STACKLEAK
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
Christoph Hellwig6630a8e2018-11-15 20:05:37 +0100147 select HAVE_EISA
Jiri Slaby5f56a5d2016-05-20 17:00:16 -0700148 select HAVE_EXIT_THREAD
Steven Rostedt (VMware)644e0e82017-03-23 10:33:52 -0400149 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
Ingo Molnar6471b822015-06-03 10:00:13 +0200150 select HAVE_FTRACE_MCOUNT_RECORD
Ingo Molnar6471b822015-06-03 10:00:13 +0200151 select HAVE_FUNCTION_GRAPH_TRACER
152 select HAVE_FUNCTION_TRACER
Emese Revfy6b90bd42016-05-24 00:09:38 +0200153 select HAVE_GCC_PLUGINS
K.Prasad0067f122009-06-01 23:43:57 +0530154 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200155 select HAVE_IDE
156 select HAVE_IOREMAP_PROT
157 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
158 select HAVE_IRQ_TIME_ACCOUNTING
159 select HAVE_KERNEL_BZIP2
160 select HAVE_KERNEL_GZIP
161 select HAVE_KERNEL_LZ4
162 select HAVE_KERNEL_LZMA
163 select HAVE_KERNEL_LZO
164 select HAVE_KERNEL_XZ
165 select HAVE_KPROBES
166 select HAVE_KPROBES_ON_FTRACE
Masami Hiramatsu540adea2018-01-13 02:55:03 +0900167 select HAVE_FUNCTION_ERROR_INJECTION
Ingo Molnar6471b822015-06-03 10:00:13 +0200168 select HAVE_KRETPROBES
169 select HAVE_KVM
170 select HAVE_LIVEPATCH if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200171 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
Joel Fernandes (Google)9f132f72019-01-03 15:28:41 -0800174 select HAVE_MOVE_PMD
Petr Mladek42a0bb32016-05-20 17:00:33 -0700175 select HAVE_NMI
Ingo Molnar6471b822015-06-03 10:00:13 +0200176 select HAVE_OPROFILE
177 select HAVE_OPTPROBES
178 select HAVE_PCSPKR_PLATFORM
179 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200180 select HAVE_PERF_EVENTS_NMI
Nicholas Piggin92e5aae2017-08-18 15:15:51 -0700181 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
Christoph Hellwigeb01d422018-11-15 20:05:32 +0100182 select HAVE_PCI
Jiri Olsac5e63192012-08-07 15:20:36 +0200183 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200184 select HAVE_PERF_USER_STACK_DUMP
Peter Zijlstra48a8b972018-08-22 17:30:16 +0200185 select HAVE_RCU_TABLE_FREE if PARAVIRT
Peter Zijlstrad86564a2018-08-22 17:30:15 +0200186 select HAVE_RCU_TABLE_INVALIDATE if HAVE_RCU_TABLE_FREE
Ingo Molnar6471b822015-06-03 10:00:13 +0200187 select HAVE_REGS_AND_STACK_ACCESS_API
Jiri Slaby6415b382018-05-18 08:47:13 +0200188 select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION
Masami Hiramatsu3c88ee194c2018-04-25 21:20:57 +0900189 select HAVE_FUNCTION_ARG_ACCESS_API
Masahiro Yamadad148eac2018-06-14 19:36:45 +0900190 select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
Ingo Molnarc763ea22016-11-15 10:26:39 +0100191 select HAVE_STACK_VALIDATION if X86_64
Mathieu Desnoyersd6761b82018-06-02 08:43:58 -0400192 select HAVE_RSEQ
Ingo Molnar6471b822015-06-03 10:00:13 +0200193 select HAVE_SYSCALL_TRACEPOINTS
Ingo Molnar6471b822015-06-03 10:00:13 +0200194 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300195 select HAVE_USER_RETURN_NOTIFIER
Thomas Gleixner05736e42018-05-29 17:48:27 +0200196 select HOTPLUG_SMT if SMP
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100197 select IRQ_FORCED_THREADING
Christoph Hellwig86596f02018-04-05 09:44:52 +0200198 select NEED_SG_DMA_LENGTH
Christoph Hellwig2eac9c22018-11-15 20:05:33 +0100199 select PCI_DOMAINS if PCI
Sinan Kaya625210c2019-01-21 23:19:58 +0000200 select PCI_LOCKLESS_CONFIG if PCI
Ingo Molnar6471b822015-06-03 10:00:13 +0200201 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500202 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200203 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200204 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500205 select SRCU
Ingo Molnar6471b822015-06-03 10:00:13 +0200206 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700207 select THREAD_INFO_IN_TASK
Ingo Molnar6471b822015-06-03 10:00:13 +0200208 select USER_STACKTRACE_SUPPORT
209 select VIRT_TO_BUS
Ingo Molnar6471b822015-06-03 10:00:13 +0200210 select X86_FEATURE_NAMES if PROC_FS
Balbir Singh7d8330a2008-02-10 12:46:28 +0530211
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200212config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100213 def_bool y
214 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200215
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700216config OUTPUT_FORMAT
217 string
218 default "elf32-i386" if X86_32
219 default "elf64-x86-64" if X86_64
220
Sam Ravnborg73531902008-05-25 23:03:18 +0200221config ARCH_DEFCONFIG
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200222 string
Sam Ravnborg73531902008-05-25 23:03:18 +0200223 default "arch/x86/configs/i386_defconfig" if X86_32
224 default "arch/x86/configs/x86_64_defconfig" if X86_64
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200225
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100226config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100227 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100228
229config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100230 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100231
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100232config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100233 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100234
Daniel Cashman9e08f572016-01-14 15:20:06 -0800235config ARCH_MMAP_RND_BITS_MIN
236 default 28 if 64BIT
237 default 8
238
239config ARCH_MMAP_RND_BITS_MAX
240 default 32 if 64BIT
241 default 16
242
243config ARCH_MMAP_RND_COMPAT_BITS_MIN
244 default 8
245
246config ARCH_MMAP_RND_COMPAT_BITS_MAX
247 default 16
248
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100249config SBUS
250 bool
251
252config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100253 def_bool y
254 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100255
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100256config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100257 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100258 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000259 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
260
261config GENERIC_BUG_RELATIVE_POINTERS
262 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100263
264config GENERIC_HWEIGHT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100265 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100266
267config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100268 def_bool y
269 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100270
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100271config RWSEM_XCHGADD_ALGORITHM
Jan Beulich3120e252012-09-10 12:41:45 +0100272 def_bool y
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100273
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100274config GENERIC_CALIBRATE_DELAY
275 def_bool y
276
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800277config ARCH_HAS_CPU_RELAX
278 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100279
Pekka Enberg1b27d052008-04-28 02:12:22 -0700280config ARCH_HAS_CACHE_LINE_SIZE
281 def_bool y
282
Dave Hansen316d0972018-04-20 15:20:28 -0700283config ARCH_HAS_FILTER_PGPROT
284 def_bool y
285
Mike Travisdd5af902008-01-30 13:33:32 +0100286config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900287 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100288
Tejun Heo08fc4582009-08-14 15:00:49 +0900289config NEED_PER_CPU_EMBED_FIRST_CHUNK
290 def_bool y
291
292config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900293 def_bool y
294
Johannes Berg801e4062007-12-08 02:12:39 +0100295config ARCH_HIBERNATION_POSSIBLE
296 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100297
Johannes Bergf4cb5702007-12-08 02:14:00 +0100298config ARCH_SUSPEND_POSSIBLE
299 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100300
Steve Cappercfe28c52013-04-29 14:29:48 +0100301config ARCH_WANT_HUGE_PMD_SHARE
302 def_bool y
303
Steve Capper53313b22013-04-30 08:03:42 +0100304config ARCH_WANT_GENERAL_HUGETLB
305 def_bool y
306
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100307config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000308 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100309
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100310config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000311 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100312
Ingo Molnar765c68b2008-04-09 11:03:37 +0200313config ARCH_SUPPORTS_OPTIMIZED_INLINING
314 def_bool y
315
Akinobu Mita6a11f752009-03-31 15:23:17 -0700316config ARCH_SUPPORTS_DEBUG_PAGEALLOC
317 def_bool y
318
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300319config KASAN_SHADOW_OFFSET
320 hex
321 depends on KASAN
322 default 0xdffffc0000000000
323
Shane Wang69575d32009-09-01 18:25:07 -0700324config HAVE_INTEL_TXT
325 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700326 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700327
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100328config X86_32_SMP
329 def_bool y
330 depends on X86_32 && SMP
331
332config X86_64_SMP
333 def_bool y
334 depends on X86_64 && SMP
335
Tejun Heoccbeed32009-02-09 22:17:40 +0900336config X86_32_LAZY_GS
337 def_bool y
Masahiro Yamada8458f8c2018-06-14 19:36:43 +0900338 depends on X86_32 && !STACKPROTECTOR
Tejun Heoccbeed32009-02-09 22:17:40 +0900339
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530340config ARCH_SUPPORTS_UPROBES
341 def_bool y
342
Rob Herringd20642f2014-04-18 17:19:54 -0500343config FIX_EARLYCON_MEM
344 def_bool y
345
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +0300346config DYNAMIC_PHYSICAL_MASK
347 bool
348
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700349config PGTABLE_LEVELS
350 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300351 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700352 default 4 if X86_64
353 default 3 if X86_PAE
354 default 2
355
Masahiro Yamada2a61f472018-05-28 18:22:00 +0900356config CC_HAS_SANE_STACKPROTECTOR
357 bool
358 default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
359 default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
360 help
361 We have to make sure stack protector is unconditionally disabled if
362 the compiler produces broken code.
363
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100364menu "Processor type and features"
365
Randy Dunlap5ee71532012-01-16 11:57:18 -0800366config ZONE_DMA
367 bool "DMA memory allocation support" if EXPERT
368 default y
369 help
370 DMA memory allocation support allows devices with less than 32-bit
371 addressing to allocate within the first 16MB of address space.
372 Disable if no such devices will be used.
373
374 If unsure, say Y.
375
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100376config SMP
377 bool "Symmetric multi-processing support"
378 ---help---
379 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800380 a system with only one CPU, say N. If you have a system with more
381 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100382
Robert Graffham4a474152014-01-23 15:55:29 -0800383 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100384 machines, but will use only one CPU of a multiprocessor machine. If
385 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800386 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100387 will run faster if you say N here.
388
389 Note that if you say Y here and choose architecture "586" or
390 "Pentium" under "Processor family", the kernel will not work on 486
391 architectures. Similarly, multiprocessor kernels for the "PPro"
392 architecture may not work on all Pentium based boards.
393
394 People using multiprocessor machines who say Y here should also say
395 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
396 Management" code will be disabled if you say Y here.
397
Paul Bolle395cf962011-08-15 02:02:26 +0200398 See also <file:Documentation/x86/i386/IO-APIC.txt>,
Benjamin Petersonc9525a32017-05-20 17:20:16 -0700399 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100400 <http://www.tldp.org/docs.html#howto>.
401
402 If you don't know what to do here, say N.
403
Josh Triplett9def39be2013-10-30 08:09:45 -0700404config X86_FEATURE_NAMES
405 bool "Processor feature human-readable names" if EMBEDDED
406 default y
407 ---help---
408 This option compiles in a table of x86 feature bits and corresponding
409 names. This is required to support /proc/cpuinfo and a few kernel
410 messages. You can disable this to save space, at the expense of
411 making those few kernel messages show numeric feature bits instead.
412
413 If in doubt, say Y.
414
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800415config X86_X2APIC
416 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200417 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800418 ---help---
419 This enables x2apic support on CPUs that have this feature.
420
421 This allows 32-bit apic IDs (so it can support very large systems),
422 and accesses the local apic via MSRs not via mmio.
423
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800424 If you don't know what to do here, say N.
425
Yinghai Lu6695c852008-06-19 12:13:09 -0700426config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700427 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000428 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200429 depends on X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100430 ---help---
Yinghai Lu6695c852008-06-19 12:13:09 -0700431 For old smp systems that do not have proper acpi support. Newer systems
432 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700433
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000434config GOLDFISH
435 def_bool y
436 depends on X86_GOLDFISH
437
David Woodhouse76b04382018-01-11 21:46:25 +0000438config RETPOLINE
439 bool "Avoid speculative indirect branches in kernel"
440 default y
Peter Zijlstrad5028ba2018-02-06 09:46:13 +0100441 select STACK_VALIDATION if HAVE_STACK_VALIDATION
David Woodhouse76b04382018-01-11 21:46:25 +0000442 help
443 Compile kernel with the retpoline compiler options to guard against
444 kernel-to-user data leaks by avoiding speculative indirect
445 branches. Requires a compiler with -mindirect-branch=thunk-extern
446 support for full protection. The kernel may run slower.
447
Johannes Weinere6d42932019-01-29 17:44:36 -0500448config X86_CPU_RESCTRL
449 bool "x86 CPU resource control support"
Babu Moger6fe07ce2018-11-21 20:28:39 +0000450 depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100451 select KERNFS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700452 help
Johannes Weinere6d42932019-01-29 17:44:36 -0500453 Enable x86 CPU resource control support.
Babu Moger6fe07ce2018-11-21 20:28:39 +0000454
455 Provide support for the allocation and monitoring of system resources
456 usage by the CPU.
457
458 Intel calls this Intel Resource Director Technology
459 (Intel(R) RDT). More information about RDT can be found in the
460 Intel x86 Architecture Software Developer Manual.
461
462 AMD calls this AMD Platform Quality of Service (AMD QoS).
463 More information about AMD QoS can be found in the AMD64 Technology
464 Platform Quality of Service Extensions manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700465
466 Say N if unsure.
467
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800468if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800469config X86_BIGSMP
470 bool "Support for big SMP systems with more than 8 CPUs"
471 depends on SMP
472 ---help---
473 This option is needed for the systems that have more than 8 CPUs
474
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800475config X86_EXTENDED_PLATFORM
476 bool "Support for extended (non-PC) x86 platforms"
477 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100478 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100479 If you disable this option then the kernel will only support
480 standard PC platforms. (which covers the vast majority of
481 systems out there.)
482
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800483 If you enable this option then you'll be able to select support
484 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100485 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800486 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800487 RDC R-321x SoC
488 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200489 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200490 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100491
492 If you have one of these systems, or if you want to build a
493 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800494endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100495
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800496if X86_64
497config X86_EXTENDED_PLATFORM
498 bool "Support for extended (non-PC) x86 platforms"
499 default y
500 ---help---
501 If you disable this option then the kernel will only support
502 standard PC platforms. (which covers the vast majority of
503 systems out there.)
504
505 If you enable this option then you'll be able to select support
506 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800507 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800508 ScaleMP vSMP
509 SGI Ultraviolet
510
511 If you have one of these systems, or if you want to build a
512 generic distribution kernel, say Y here - otherwise say N.
513endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800514# This is an alphabetically sorted list of 64 bit extended platforms
515# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800516config X86_NUMACHIP
517 bool "Numascale NumaChip"
518 depends on X86_64
519 depends on X86_EXTENDED_PLATFORM
520 depends on NUMA
521 depends on SMP
522 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700523 depends on PCI_MMCONFIG
Steffen Persvold44b111b52011-12-06 00:07:26 +0800524 ---help---
525 Adds support for Numascale NumaChip large-SMP systems. Needed to
526 enable more than ~168 cores.
527 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100528
Ingo Molnar6a485652009-01-27 18:29:13 +0100529config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800530 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100531 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100532 select PARAVIRT
533 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800534 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300535 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100536 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100537 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
538 supposed to run on these EM64T-based machines. Only choose this option
539 if you have one of these machines.
540
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800541config X86_UV
542 bool "SGI Ultraviolet"
543 depends on X86_64
544 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500545 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800546 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700547 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200548 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800549 ---help---
550 This option is needed in order to support SGI Ultraviolet systems.
551 If you don't have one of these, you should say N here.
552
553# Following is an alphabetically sorted list of 32 bit extended platforms
554# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100555
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000556config X86_GOLDFISH
557 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100558 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000559 ---help---
560 Enable support for the Goldfish virtual platform used primarily
561 for Android development. Unless you are building for the Android
562 Goldfish emulator say N here.
563
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800564config X86_INTEL_CE
565 bool "CE4100 TV platform"
566 depends on PCI
567 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800568 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800569 depends on X86_32
570 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800571 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100572 select OF
573 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800574 ---help---
575 Select for the Intel CE media processor (CE4100) SOC.
576 This option compiles in support for the CE4100 SOC for settop
577 boxes and media devices.
578
David Cohen4cb9b002013-12-16 17:37:26 -0800579config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100580 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100581 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800582 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000583 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200584 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000585 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000586 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800587 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000588 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000589 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000590 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000591 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000592 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800593 Select to build a kernel capable of supporting Intel MID (Mobile
594 Internet Device) platform systems which do not have the PCI legacy
595 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000596
David Cohen4cb9b002013-12-16 17:37:26 -0800597 Intel MID platforms are based on an Intel processor and chipset which
598 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100599
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000600config X86_INTEL_QUARK
601 bool "Intel Quark platform support"
602 depends on X86_32
603 depends on X86_EXTENDED_PLATFORM
604 depends on X86_PLATFORM_DEVICES
605 depends on X86_TSC
606 depends on PCI
607 depends on PCI_GOANY
608 depends on X86_IO_APIC
609 select IOSF_MBI
610 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200611 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000612 ---help---
613 Select to include support for Quark X1000 SoC.
614 Say Y here if you have a Quark based system such as the Arduino
615 compatible Intel Galileo.
616
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000617config X86_INTEL_LPSS
618 bool "Intel Low Power Subsystem Support"
Sinan Kaya5962dd22019-01-02 18:10:37 +0000619 depends on X86 && ACPI && PCI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000620 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300621 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100622 select IOSF_MBI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000623 ---help---
624 Select to build support for Intel Low Power Subsystem such as
625 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300626 things like clock tree (common clock framework) and pincontrol
627 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000628
Ken Xue92082a82015-02-06 08:27:51 +0800629config X86_AMD_PLATFORM_DEVICE
630 bool "AMD ACPI2Platform devices support"
631 depends on ACPI
632 select COMMON_CLK
633 select PINCTRL
634 ---help---
635 Select to interpret AMD specific ACPI device to platform device
636 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
637 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
638 implemented under PINCTRL subsystem.
639
David E. Boxced3ce72014-09-17 22:13:50 -0700640config IOSF_MBI
641 tristate "Intel SoC IOSF Sideband support for SoC platforms"
642 depends on PCI
643 ---help---
644 This option enables sideband register access support for Intel SoC
645 platforms. On these platforms the IOSF sideband is used in lieu of
646 MSR's for some register accesses, mostly but not limited to thermal
647 and power. Drivers may query the availability of this device to
648 determine if they need the sideband in order to work on these
649 platforms. The sideband is available on the following SoC products.
650 This list is not meant to be exclusive.
651 - BayTrail
652 - Braswell
653 - Quark
654
655 You should say Y if you are running a kernel on one of these SoC's.
656
David E. Boxed2226b2014-09-17 22:13:51 -0700657config IOSF_MBI_DEBUG
658 bool "Enable IOSF sideband access through debugfs"
659 depends on IOSF_MBI && DEBUG_FS
660 ---help---
661 Select this option to expose the IOSF sideband access registers (MCR,
662 MDR, MCRX) through debugfs to write and read register information from
663 different units on the SoC. This is most useful for obtaining device
664 state information for debug and analysis. As this is a general access
665 mechanism, users of this option would have specific knowledge of the
666 device they want to access.
667
668 If you don't require the option or are in doubt, say N.
669
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800670config X86_RDC321X
671 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100672 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800673 depends on X86_EXTENDED_PLATFORM
674 select M486
675 select X86_REBOOTFIXUPS
676 ---help---
677 This option is needed for RDC R-321x system-on-chip, also known
678 as R-8610-(G).
679 If you don't have one of these chips, you should say N here.
680
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100681config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100682 bool "Support non-standard 32-bit SMP architectures"
683 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800684 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100685 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800686 This option compiles in the bigsmp and STA2X11 default
687 subarchitectures. It is intended for a generic binary
688 kernel. If you select them all, kernel will probe it one by
689 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700690
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800691# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700692
Linus Torvaldsd949f362009-09-26 09:35:07 -0700693config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100694 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700695 # MCE code calls memory_failure():
696 depends on X86_MCE
697 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700698 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
699 depends on X86_64 || !SPARSEMEM
700 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700701
Alessandro Rubini83125a32012-04-04 19:40:21 +0200702config STA2X11
703 bool "STA2X11 Companion Chip Support"
704 depends on X86_32_NON_STANDARD && PCI
Christoph Hellwigb6e05472018-03-19 11:38:24 +0100705 select ARCH_HAS_PHYS_TO_DMA
Alessandro Rubini83125a32012-04-04 19:40:21 +0200706 select X86_DEV_DMA_OPS
707 select X86_DMA_REMAP
708 select SWIOTLB
709 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200710 select GPIOLIB
Alessandro Rubini83125a32012-04-04 19:40:21 +0200711 ---help---
712 This adds support for boards based on the STA2X11 IO-Hub,
713 a.k.a. "ConneXt". The chip is used in place of the standard
714 PC chipset, so all "standard" peripherals are missing. If this
715 option is selected the kernel will still be able to boot on
716 standard PC machines.
717
Shérab82148d12010-09-25 06:06:57 +0200718config X86_32_IRIS
719 tristate "Eurobraille/Iris poweroff module"
720 depends on X86_32
721 ---help---
722 The Iris machines from EuroBraille do not have APM or ACPI support
723 to shut themselves down properly. A special I/O sequence is
724 needed to do so, which is what this module does at
725 kernel shutdown.
726
727 This is only for Iris machines from EuroBraille.
728
729 If unused, say N.
730
Ingo Molnarae1e9132008-11-11 09:05:16 +0100731config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100732 def_bool y
733 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800734 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100735 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100736 Calculate simpler /proc/<PID>/wchan values. If this option
737 is disabled then wchan values will recurse back to the
738 caller function. This provides more accurate wchan values,
739 at the expense of slightly more scheduling overhead.
740
741 If in doubt, say "Y".
742
Borislav Petkov6276a072013-03-04 21:20:21 +0100743menuconfig HYPERVISOR_GUEST
744 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100745 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100746 Say Y here to enable options for running Linux under various hyper-
747 visors. This option enables basic hypervisor detection and platform
748 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100749
Borislav Petkov6276a072013-03-04 21:20:21 +0100750 If you say N, all options in this submenu will be skipped and
751 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100752
Borislav Petkov6276a072013-03-04 21:20:21 +0100753if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100754
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100755config PARAVIRT
756 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100757 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100758 This changes the kernel so it can modify itself when it is run
759 under a hypervisor, potentially improving performance significantly
760 over full virtualization. However, when run without a hypervisor
761 the kernel is theoretically slower and slightly larger.
762
Juergen Grossc00a2802018-08-28 09:40:21 +0200763config PARAVIRT_XXL
764 bool
765
Borislav Petkov6276a072013-03-04 21:20:21 +0100766config PARAVIRT_DEBUG
767 bool "paravirt-ops debugging"
768 depends on PARAVIRT && DEBUG_KERNEL
769 ---help---
770 Enable to debug paravirt_ops internals. Specifically, BUG if
771 a paravirt_op is missing when it is called.
772
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700773config PARAVIRT_SPINLOCKS
774 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700775 depends on PARAVIRT && SMP
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700776 ---help---
777 Paravirtualized spinlocks allow a pvops backend to replace the
778 spinlock implementation with something virtualization-friendly
779 (for example, block the virtual CPU rather than spinning).
780
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530781 It has a minimal impact on native kernels and gives a nice performance
782 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700783
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530784 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700785
Waiman Long45e898b2015-11-09 19:09:25 -0500786config QUEUED_LOCK_STAT
787 bool "Paravirt queued spinlock statistics"
Peter Zijlstracfd89832016-05-18 20:43:02 +0200788 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
Waiman Long45e898b2015-11-09 19:09:25 -0500789 ---help---
790 Enable the collection of statistical data on the slowpath
791 behavior of paravirtualized queued spinlocks and report
792 them on debugfs.
793
Borislav Petkov6276a072013-03-04 21:20:21 +0100794source "arch/x86/xen/Kconfig"
795
796config KVM_GUEST
797 bool "KVM Guest support (including kvmclock)"
798 depends on PARAVIRT
799 select PARAVIRT_CLOCK
800 default y
801 ---help---
802 This option enables various optimizations for running under the KVM
803 hypervisor. It includes a paravirtualized clock, so that instead
804 of relying on a PIT (or probably other) emulation by the
805 underlying device model, the host provides the guest with
806 timing infrastructure such as time of day, and system time
807
Maran Wilson77336072018-12-10 11:07:28 -0800808config PVH
809 bool "Support for running PVH guests"
810 ---help---
811 This option enables the PVH entry point for guest virtual machines
812 as specified in the x86/HVM direct boot ABI.
813
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530814config KVM_DEBUG_FS
815 bool "Enable debug information for KVM Guests in debugfs"
816 depends on KVM_GUEST && DEBUG_FS
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530817 ---help---
818 This option enables collection of various statistics for KVM guest.
819 Statistics are displayed in debugfs filesystem. Enabling this option
820 may incur significant overhead.
821
Borislav Petkov6276a072013-03-04 21:20:21 +0100822config PARAVIRT_TIME_ACCOUNTING
823 bool "Paravirtual steal time accounting"
824 depends on PARAVIRT
Borislav Petkov6276a072013-03-04 21:20:21 +0100825 ---help---
826 Select this option to enable fine granularity task steal time
827 accounting. Time spent executing other tasks in parallel with
828 the current vCPU is discounted from the vCPU power. To account for
829 that, there can be a small performance impact.
830
831 If in doubt, say N here.
832
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200833config PARAVIRT_CLOCK
834 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200835
Jan Kiszka4a362602017-11-27 09:11:46 +0100836config JAILHOUSE_GUEST
837 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100838 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100839 select X86_PM_TIMER
Jan Kiszka4a362602017-11-27 09:11:46 +0100840 ---help---
841 This option allows to run Linux as guest in a Jailhouse non-root
842 cell. You can leave this option disabled if you only want to start
843 Jailhouse and run Linux afterwards in the root cell.
844
Borislav Petkov6276a072013-03-04 21:20:21 +0100845endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400846
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100847source "arch/x86/Kconfig.cpu"
848
849config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100850 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100851 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100852 ---help---
853 Use the IA-PC HPET (High Precision Event Timer) to manage
854 time in preference to the PIT and RTC, if a HPET is
855 present.
856 HPET is the next generation timer replacing legacy 8254s.
857 The HPET provides a stable time base on SMP
858 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200859 as it is off-chip. The interface used is documented
860 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100861
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100862 You can safely choose Y here. However, HPET will only be
863 activated if the platform and the BIOS support this feature.
864 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100865
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100866 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100867
868config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100869 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800870 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100871
Jacob Panbb24c472009-09-02 07:37:17 -0700872config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000873 def_bool y if X86_INTEL_MID
874 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100875 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000876 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700877 help
878 APB timer is the replacement for 8254, HPET on X86 MID platforms.
879 The APBT provides a stable time base on SMP
880 systems, unlike the TSC, but it is more expensive to access,
881 as it is off-chip. APB timers are always running regardless of CPU
882 C states, they are used as per CPU clockevent device when possible.
883
David Rientjes6a108a12011-01-20 14:44:16 -0800884# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100885# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700886config DMI
887 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800888 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800889 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100890 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700891 Enabled scanning of DMI to identify machine quirks. Say Y
892 here unless you have verified that your setup is not
893 affected by entries in the DMI blacklist. Required by PNP
894 BIOS code.
895
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100896config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700897 bool "Old AMD GART IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200898 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100899 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200900 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100901 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200902 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
903 GART based hardware IOMMUs.
904
905 The GART supports full DMA access for devices with 32-bit access
906 limitations, on systems with more than 3 GB. This is usually needed
907 for USB, sound, many IDE/SATA chipsets and some other devices.
908
909 Newer systems typically have a modern AMD IOMMU, supported via
910 the CONFIG_AMD_IOMMU=y config option.
911
912 In normal configurations this driver is only active when needed:
913 there's more than 3 GB of memory and the system contains a
914 32-bit limited device.
915
916 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100917
918config CALGARY_IOMMU
919 bool "IBM Calgary IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200920 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100921 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700922 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100923 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100924 Support for hardware IOMMUs in IBM's xSeries x366 and x460
925 systems. Needed to run systems with more than 3GB of memory
926 properly with 32-bit PCI devices that do not support DAC
927 (Double Address Cycle). Calgary also supports bus level
928 isolation, where all DMAs pass through the IOMMU. This
929 prevents them from going anywhere except their intended
930 destination. This catches hard-to-find kernel bugs and
931 mis-behaving drivers and devices that do not use the DMA-API
932 properly to set up their DMA buffers. The IOMMU can be
933 turned off at boot time with the iommu=off parameter.
934 Normally the kernel will make the right choice by itself.
935 If unsure, say Y.
936
937config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100938 def_bool y
939 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100940 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100941 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100942 Should Calgary be enabled by default? if you choose 'y', Calgary
943 will be used (if it exists). If you choose 'n', Calgary will not be
944 used even if it exists. If you choose 'n' and would like to use
945 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
946 If unsure, say Y.
947
Mike Travis1184dc22008-05-12 21:21:12 +0200948config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200949 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700950 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800951 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100952 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200953 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200954 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100955
Ingo Molnaraec64872018-02-10 12:36:29 +0100956#
957# The maximum number of CPUs supported:
958#
959# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
960# and which can be configured interactively in the
961# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
962#
963# The ranges are different on 32-bit and 64-bit kernels, depending on
964# hardware capabilities and scalability features of the kernel.
965#
966# ( If MAXSMP is enabled we just use the highest possible value and disable
967# interactive configuration. )
968#
969
970config NR_CPUS_RANGE_BEGIN
971 int
972 default NR_CPUS_RANGE_END if MAXSMP
973 default 1 if !SMP
974 default 2
975
976config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800977 int
978 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100979 default 64 if SMP && X86_BIGSMP
980 default 8 if SMP && !X86_BIGSMP
981 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800982
Ingo Molnaraec64872018-02-10 12:36:29 +0100983config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800984 int
985 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100986 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
987 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
988 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800989
Ingo Molnaraec64872018-02-10 12:36:29 +0100990config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800991 int
992 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100993 default 32 if X86_BIGSMP
994 default 8 if SMP
995 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800996
Ingo Molnaraec64872018-02-10 12:36:29 +0100997config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800998 int
999 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +01001000 default 8192 if MAXSMP
1001 default 64 if SMP
1002 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -08001003
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001004config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -08001005 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +01001006 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
1007 default NR_CPUS_DEFAULT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001008 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001009 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -05001010 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +03001011 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001012 minimum value which makes sense is 2.
1013
Ingo Molnaraec64872018-02-10 12:36:29 +01001014 This is purely to save memory: each supported CPU adds about 8KB
1015 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001016
1017config SCHED_SMT
Thomas Gleixnerdbe73362018-11-25 19:33:37 +01001018 def_bool y if SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001019
1020config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001021 def_bool y
1022 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001023 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001024 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001025 Multi-core scheduler support improves the CPU scheduler's decision
1026 making when dealing with multi-core CPU chips at a cost of slightly
1027 increased overhead in some places. If unsure say N here.
1028
Tim Chende966cf2016-11-29 10:43:27 -08001029config SCHED_MC_PRIO
1030 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001031 depends on SCHED_MC && CPU_SUP_INTEL
1032 select X86_INTEL_PSTATE
1033 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001034 default y
Tim Chen5e76b2a2016-11-22 12:23:55 -08001035 ---help---
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001036 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1037 core ordering determined at manufacturing time, which allows
1038 certain cores to reach higher turbo frequencies (when running
1039 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001040
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001041 Enabling this kernel feature teaches the scheduler about
1042 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1043 scheduler's CPU selection logic accordingly, so that higher
1044 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001045
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001046 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001047
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001048 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001049
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001050config UP_LATE_INIT
1051 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +01001052 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001053
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001054config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001055 bool "Local APIC support on uniprocessors" if !PCI_MSI
1056 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001057 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001058 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001059 A local APIC (Advanced Programmable Interrupt Controller) is an
1060 integrated interrupt controller in the CPU. If you have a single-CPU
1061 system which has a processor with a local APIC, you can say Y here to
1062 enable and use it. If you say Y here even though your machine doesn't
1063 have a local APIC, then the kernel will still run with no slowdown at
1064 all. The local APIC supports CPU-generated self-interrupts (timer,
1065 performance counters), and the NMI watchdog which detects hard
1066 lockups.
1067
1068config X86_UP_IOAPIC
1069 bool "IO-APIC support on uniprocessors"
1070 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001071 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001072 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1073 SMP-capable replacement for PC-style interrupt controllers. Most
1074 SMP systems and many recent uniprocessor systems have one.
1075
1076 If you have a single-CPU system with an IO-APIC, you can say Y here
1077 to use it. If you say Y here even though your machine doesn't have
1078 an IO-APIC, then the kernel will still run with no slowdown at all.
1079
1080config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001081 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001082 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001083 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001084 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001085
1086config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001087 def_bool y
1088 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001089
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001090config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1091 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001092 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001093 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001094 This option enables a workaround that fixes a source of
1095 spurious interrupts. This is recommended when threaded
1096 interrupt handling is used on systems where the generation of
1097 superfluous "boot interrupts" cannot be disabled.
1098
1099 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1100 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1101 kernel does during interrupt handling). On chipsets where this
1102 boot IRQ generation cannot be disabled, this workaround keeps
1103 the original IRQ line masked so that only the equivalent "boot
1104 IRQ" is delivered to the CPUs. The workaround also tells the
1105 kernel to set up the IRQ handler on the boot IRQ line. In this
1106 way only one interrupt is delivered to the kernel. Otherwise
1107 the spurious second interrupt may cause the kernel to bring
1108 down (vital) interrupt lines.
1109
1110 Only affects "broken" chipsets. Interrupt sharing may be
1111 increased on these systems.
1112
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001113config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001114 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001115 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001116 default y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001117 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +02001118 Machine Check support allows the processor to notify the
1119 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001120 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001121 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001122
Tony Luck5de97c92017-03-27 11:33:03 +02001123config X86_MCELOG_LEGACY
1124 bool "Support for deprecated /dev/mcelog character device"
1125 depends on X86_MCE
1126 ---help---
1127 Enable support for /dev/mcelog which is needed by the old mcelog
1128 userspace logging daemon. Consider switching to the new generation
1129 rasdaemon solution.
1130
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001131config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001132 def_bool y
1133 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001134 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001135 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001136 Additional support for intel specific MCE features such as
1137 the thermal monitor.
1138
1139config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001140 def_bool y
1141 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001142 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001143 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001144 Additional support for AMD specific MCE features such as
1145 the DRAM Error Threshold.
1146
Andi Kleen4efc0672009-04-28 19:07:31 +02001147config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001148 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001149 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001150 ---help---
1151 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001152 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001153 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001154
Andi Kleenb2762682009-02-12 13:49:31 +01001155config X86_MCE_THRESHOLD
1156 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001157 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001158
Andi Kleenea149b32009-04-29 19:31:00 +02001159config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001160 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001161 tristate "Machine check injector support"
1162 ---help---
1163 Provide support for injecting machine checks for testing purposes.
1164 If you don't know what a machine check is and you don't do kernel
1165 QA it is safe to say n.
1166
Andi Kleen4efc0672009-04-28 19:07:31 +02001167config X86_THERMAL_VECTOR
1168 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001169 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001170
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001171source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001172
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001173config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001174 bool "Legacy VM86 support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001175 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001176 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001177 This option allows user programs to put the CPU into V8086
1178 mode, which is an 80286-era approximation of 16-bit real mode.
1179
1180 Some very old versions of X and/or vbetool require this option
1181 for user mode setting. Similarly, DOSEMU will use it if
1182 available to accelerate real mode DOS programs. However, any
1183 recent version of DOSEMU, X, or vbetool should be fully
1184 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001185 fall back to software emulation. Nevertheless, if you are using
1186 a 16-bit DOS program where 16-bit performance matters, vm86
1187 mode might be faster than emulation and you might want to
1188 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001189
Ingo Molnar1e642812015-09-05 08:58:10 +02001190 Note that any app that works on a 64-bit kernel is unlikely to
1191 need this option, as 64-bit kernels don't, and can't, support
1192 V8086 mode. This option is also unrelated to 16-bit protected
1193 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001194
Ingo Molnar1e642812015-09-05 08:58:10 +02001195 Enabling this option increases the complexity of the kernel
1196 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001197
Ingo Molnar1e642812015-09-05 08:58:10 +02001198 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001199
1200config VM86
1201 bool
1202 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001203
1204config X86_16BIT
1205 bool "Enable support for 16-bit segments" if EXPERT
1206 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001207 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001208 ---help---
1209 This option is required by programs like Wine to run 16-bit
1210 protected mode legacy code on x86 processors. Disabling
1211 this option saves about 300 bytes on i386, or around 6K text
1212 plus 16K runtime memory on x86-64,
1213
1214config X86_ESPFIX32
1215 def_bool y
1216 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001217
H. Peter Anvin197725d2014-05-04 10:00:49 -07001218config X86_ESPFIX64
1219 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001220 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001221
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001222config X86_VSYSCALL_EMULATION
1223 bool "Enable vsyscall emulation" if EXPERT
1224 default y
1225 depends on X86_64
1226 ---help---
1227 This enables emulation of the legacy vsyscall page. Disabling
1228 it is roughly equivalent to booting with vsyscall=none, except
1229 that it will also disable the helpful warning if a program
1230 tries to use a vsyscall. With this option set to N, offending
1231 programs will just segfault, citing addresses of the form
1232 0xffffffffff600?00.
1233
1234 This option is required by many programs built before 2013, and
1235 care should be used even with newer programs if set to N.
1236
1237 Disabling this option saves about 7K of kernel size and
1238 possibly 4K of additional runtime pagetable memory.
1239
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001240config TOSHIBA
1241 tristate "Toshiba Laptop support"
1242 depends on X86_32
1243 ---help---
1244 This adds a driver to safely access the System Management Mode of
1245 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1246 not work on models with a Phoenix BIOS. The System Management Mode
1247 is used to set the BIOS and power saving options on Toshiba portables.
1248
1249 For information on utilities to make use of this driver see the
1250 Toshiba Linux utilities web site at:
1251 <http://www.buzzard.org.uk/toshiba/>.
1252
1253 Say Y if you intend to run this kernel on a Toshiba portable.
1254 Say N otherwise.
1255
1256config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001257 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001258 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001259 select SENSORS_DELL_SMM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001260 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001261 This option enables legacy /proc/i8k userspace interface in hwmon
1262 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1263 temperature and allows controlling fan speeds of Dell laptops via
1264 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1265 it reports also power and hotkey status. For fan speed control is
1266 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001267
Pali Rohár039ae582015-05-14 13:16:37 +02001268 Say Y if you intend to run this kernel on old Dell laptops or want to
1269 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001270 Say N otherwise.
1271
1272config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001273 bool "Enable X86 board specific fixups for reboot"
1274 depends on X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001275 ---help---
1276 This enables chipset and/or board specific fixups to be done
1277 in order to get reboot to work correctly. This is only needed on
1278 some combinations of hardware and BIOS. The symptom, for which
1279 this config is intended, is when reboot ends with a stalled/hung
1280 system.
1281
1282 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001283 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001284
1285 Say Y if you want to enable the fixup. Currently, it's safe to
1286 enable this option even if you don't need it.
1287 Say N otherwise.
1288
1289config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001290 bool "CPU microcode loading support"
1291 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001292 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001293 select FW_LOADER
1294 ---help---
1295 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001296 Intel and AMD processors. The Intel support is for the IA32 family,
1297 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1298 AMD support is for families 0x10 and later. You will obviously need
1299 the actual microcode binary data itself which is not shipped with
1300 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001301
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001302 The preferred method to load microcode from a detached initrd is described
Jaak Ristioja1897a962018-02-09 11:22:16 +02001303 in Documentation/x86/microcode.txt. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001304 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1305 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001306
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001307 In addition, you can build the microcode into the kernel. For that you
1308 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1309 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001310
Peter Oruba8d86f392008-07-28 18:44:21 +02001311config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001312 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001313 depends on MICROCODE
1314 default MICROCODE
1315 select FW_LOADER
1316 ---help---
1317 This options enables microcode patch loading support for Intel
1318 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001319
Alanb8989db2014-01-20 18:01:56 +00001320 For the current Intel microcode data package go to
1321 <https://downloadcenter.intel.com> and search for
1322 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001323
Peter Oruba80cc9f12008-07-28 18:44:22 +02001324config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001325 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001326 depends on MICROCODE
1327 select FW_LOADER
1328 ---help---
1329 If you select this option, microcode patch loading support for AMD
1330 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001331
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001332config MICROCODE_OLD_INTERFACE
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001333 bool "Ancient loading interface (DEPRECATED)"
1334 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001335 depends on MICROCODE
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001336 ---help---
1337 DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface
1338 which was used by userspace tools like iucode_tool and microcode.ctl.
1339 It is inadequate because it runs too late to be able to properly
1340 load microcode on a machine and it needs special tools. Instead, you
1341 should've switched to the early loading method with the initrd or
1342 builtin microcode by now: Documentation/x86/microcode.txt
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001343
1344config X86_MSR
1345 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001346 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001347 This device gives privileged processes access to the x86
1348 Model-Specific Registers (MSRs). It is a character device with
1349 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1350 MSR accesses are directed to a specific CPU on multi-processor
1351 systems.
1352
1353config X86_CPUID
1354 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001355 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001356 This device gives processes access to the x86 CPUID instruction to
1357 be executed on a specific processor. It is a character device
1358 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1359 /dev/cpu/31/cpuid.
1360
1361choice
1362 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001363 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001364 depends on X86_32
1365
1366config NOHIGHMEM
1367 bool "off"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001368 ---help---
1369 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1370 However, the address space of 32-bit x86 processors is only 4
1371 Gigabytes large. That means that, if you have a large amount of
1372 physical memory, not all of it can be "permanently mapped" by the
1373 kernel. The physical memory that's not permanently mapped is called
1374 "high memory".
1375
1376 If you are compiling a kernel which will never run on a machine with
1377 more than 1 Gigabyte total physical RAM, answer "off" here (default
1378 choice and suitable for most users). This will result in a "3GB/1GB"
1379 split: 3GB are mapped so that each process sees a 3GB virtual memory
1380 space and the remaining part of the 4GB virtual memory space is used
1381 by the kernel to permanently map as much physical memory as
1382 possible.
1383
1384 If the machine has between 1 and 4 Gigabytes physical RAM, then
1385 answer "4GB" here.
1386
1387 If more than 4 Gigabytes is used then answer "64GB" here. This
1388 selection turns Intel PAE (Physical Address Extension) mode on.
1389 PAE implements 3-level paging on IA32 processors. PAE is fully
1390 supported by Linux, PAE mode is implemented on all recent Intel
1391 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1392 then the kernel will not boot on CPUs that don't support PAE!
1393
1394 The actual amount of total physical memory will either be
1395 auto detected or can be forced by using a kernel command line option
1396 such as "mem=256M". (Try "man bootparam" or see the documentation of
1397 your boot loader (lilo or loadlin) about how to pass options to the
1398 kernel at boot time.)
1399
1400 If unsure, say "off".
1401
1402config HIGHMEM4G
1403 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001404 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001405 Select this if you have a 32-bit processor and between 1 and 4
1406 gigabytes of physical RAM.
1407
1408config HIGHMEM64G
1409 bool "64GB"
Matthew Whitehead69b8d3f2018-02-15 11:54:55 -05001410 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001411 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001412 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001413 Select this if you have a 32-bit processor and more than 4
1414 gigabytes of physical RAM.
1415
1416endchoice
1417
1418choice
David Rientjes6a108a12011-01-20 14:44:16 -08001419 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001420 default VMSPLIT_3G
1421 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001422 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001423 Select the desired split between kernel and user memory.
1424
1425 If the address range available to the kernel is less than the
1426 physical memory installed, the remaining memory will be available
1427 as "high memory". Accessing high memory is a little more costly
1428 than low memory, as it needs to be mapped into the kernel first.
1429 Note that increasing the kernel address space limits the range
1430 available to user programs, making the address space there
1431 tighter. Selecting anything other than the default 3G/1G split
1432 will also likely make your kernel incompatible with binary-only
1433 kernel modules.
1434
1435 If you are not absolutely sure what you are doing, leave this
1436 option alone!
1437
1438 config VMSPLIT_3G
1439 bool "3G/1G user/kernel split"
1440 config VMSPLIT_3G_OPT
1441 depends on !X86_PAE
1442 bool "3G/1G user/kernel split (for full 1G low memory)"
1443 config VMSPLIT_2G
1444 bool "2G/2G user/kernel split"
1445 config VMSPLIT_2G_OPT
1446 depends on !X86_PAE
1447 bool "2G/2G user/kernel split (for full 2G low memory)"
1448 config VMSPLIT_1G
1449 bool "1G/3G user/kernel split"
1450endchoice
1451
1452config PAGE_OFFSET
1453 hex
1454 default 0xB0000000 if VMSPLIT_3G_OPT
1455 default 0x80000000 if VMSPLIT_2G
1456 default 0x78000000 if VMSPLIT_2G_OPT
1457 default 0x40000000 if VMSPLIT_1G
1458 default 0xC0000000
1459 depends on X86_32
1460
1461config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001462 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001463 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001464
1465config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001466 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001467 depends on X86_32 && !HIGHMEM4G
Christoph Hellwigd4a451d2018-04-03 16:24:20 +02001468 select PHYS_ADDR_T_64BIT
Christian Melki9d99c712015-10-05 17:31:33 +02001469 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001470 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001471 PAE is required for NX support, and furthermore enables
1472 larger swapspace support for non-overcommit purposes. It
1473 has the cost of more pagetable lookup overhead, and also
1474 consumes more pagetable space per process.
1475
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001476config X86_5LEVEL
1477 bool "Enable 5-level page tables support"
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001478 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001479 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001480 depends on X86_64
1481 ---help---
1482 5-level paging enables access to larger address space:
1483 upto 128 PiB of virtual address space and 4 PiB of
1484 physical address space.
1485
1486 It will be supported by future Intel CPUs.
1487
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001488 A kernel with the option enabled can be booted on machines that
1489 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001490
1491 See Documentation/x86/x86_64/5level-paging.txt for more
1492 information.
1493
1494 Say N if unsure.
1495
Ingo Molnar10971ab2015-03-05 08:18:23 +01001496config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001497 def_bool y
Levin, Alexander (Sasha Levin)4675ff02017-11-15 17:36:02 -08001498 depends on X86_64 && !DEBUG_PAGEALLOC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001499 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001500 Certain kernel features effectively disable kernel
1501 linear 1 GB mappings (even if the CPU otherwise
1502 supports them), so don't confuse the user by printing
1503 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001504
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001505config X86_CPA_STATISTICS
1506 bool "Enable statistic for Change Page Attribute"
1507 depends on DEBUG_FS
1508 ---help---
1509 Expose statistics about the Change Page Attribute mechanims, which
1510 helps to determine the effectivness of preserving large and huge
1511 page mappings when mapping protections are changed.
1512
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001513config ARCH_HAS_MEM_ENCRYPT
1514 def_bool y
1515
1516config AMD_MEM_ENCRYPT
1517 bool "AMD Secure Memory Encryption (SME) support"
1518 depends on X86_64 && CPU_SUP_AMD
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +03001519 select DYNAMIC_PHYSICAL_MASK
Ard Biesheuvelce9084b2019-02-02 10:41:17 +01001520 select ARCH_USE_MEMREMAP_PROT
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001521 ---help---
1522 Say yes to enable support for the encryption of system memory.
1523 This requires an AMD processor that supports Secure Memory
1524 Encryption (SME).
1525
1526config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1527 bool "Activate AMD Secure Memory Encryption (SME) by default"
1528 default y
1529 depends on AMD_MEM_ENCRYPT
1530 ---help---
1531 Say yes to have system memory encrypted by default if running on
1532 an AMD processor that supports Secure Memory Encryption (SME).
1533
1534 If set to Y, then the encryption of system memory can be
1535 deactivated with the mem_encrypt=off command line option.
1536
1537 If set to N, then the encryption of system memory can be
1538 activated with the mem_encrypt=on command line option.
1539
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001540# Common NUMA Features
1541config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001542 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001543 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001544 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1545 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001546 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001547 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001548
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001549 The kernel will try to allocate memory used by a CPU on the
1550 local memory controller of the CPU and add some more
1551 NUMA awareness to the kernel.
1552
Ingo Molnarc280ea52008-11-08 13:29:45 +01001553 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001554 (or later), AMD Opteron, or EM64T NUMA.
1555
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001556 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001557 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001558
1559 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001560
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001561config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001562 def_bool y
1563 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001564 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001565 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001566 Enable AMD NUMA node topology detection. You should say Y here if
1567 you have a multi processor AMD system. This uses an old method to
1568 read the NUMA configuration directly from the builtin Northbridge
1569 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1570 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001571
1572config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001573 def_bool y
1574 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001575 depends on X86_64 && NUMA && ACPI && PCI
1576 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001577 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001578 Enable ACPI SRAT based node topology detection.
1579
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001580# Some NUMA nodes have memory ranges that span
1581# other nodes. Even though a pfn is valid and
1582# between a node's start and end pfns, it may not
1583# reside on that node. See memmap_init_zone()
1584# for details.
1585config NODES_SPAN_OTHER_NODES
1586 def_bool y
1587 depends on X86_64_ACPI_NUMA
1588
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001589config NUMA_EMU
1590 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001591 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001592 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001593 Enable NUMA emulation. A flat machine will be split
1594 into virtual nodes when booted with "numa=fake=N", where N is the
1595 number of nodes. This is only useful for debugging.
1596
1597config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001598 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001599 range 1 10
1600 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001601 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001602 default "3"
1603 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001604 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001605 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001606 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001607
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001608config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001609 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001610 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001611
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001612config ARCH_FLATMEM_ENABLE
1613 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001614 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001615
1616config ARCH_DISCONTIGMEM_ENABLE
1617 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001618 depends on NUMA && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001619
1620config ARCH_DISCONTIGMEM_DEFAULT
1621 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001622 depends on NUMA && X86_32
1623
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001624config ARCH_SPARSEMEM_ENABLE
1625 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001626 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001627 select SPARSEMEM_STATIC if X86_32
1628 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1629
Tejun Heo3b166512011-04-01 11:15:12 +02001630config ARCH_SPARSEMEM_DEFAULT
1631 def_bool y
1632 depends on X86_64
1633
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001634config ARCH_SELECT_MEMORY_MODEL
1635 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001636 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001637
1638config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001639 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001640 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001641 help
1642 This option enables a sysfs memory/probe interface for testing.
1643 See Documentation/memory-hotplug.txt for more information.
1644 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001645
Tejun Heo3b166512011-04-01 11:15:12 +02001646config ARCH_PROC_KCORE_TEXT
1647 def_bool y
1648 depends on X86_64 && PROC_KCORE
1649
Avi Kivitya29815a2010-01-10 16:28:09 +02001650config ILLEGAL_POINTER_VALUE
1651 hex
1652 default 0 if X86_32
1653 default 0xdead000000000000 if X86_64
1654
Dan Williams7a678322015-08-19 00:34:34 -04001655config X86_PMEM_LEGACY_DEVICE
1656 bool
1657
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001658config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001659 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001660 depends on PHYS_ADDR_T_64BIT
1661 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001662 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001663 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001664 help
1665 Treat memory marked using the non-standard e820 type of 12 as used
1666 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1667 The kernel will offer these regions to the 'pmem' driver so
1668 they can be used for persistent storage.
1669
1670 Say Y if unsure.
1671
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001672config HIGHPTE
1673 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001674 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001675 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001676 The VM uses one page table entry for each page of physical memory.
1677 For systems with a lot of RAM, this can be wasteful of precious
1678 low memory. Setting this option will put user-space page table
1679 entries in high memory.
1680
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001681config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001682 bool "Check for low memory corruption"
1683 ---help---
1684 Periodically check for memory corruption in low memory, which
1685 is suspected to be caused by BIOS. Even when enabled in the
1686 configuration, it is disabled at runtime. Enable it by
1687 setting "memory_corruption_check=1" on the kernel command
1688 line. By default it scans the low 64k of memory every 60
1689 seconds; see the memory_corruption_check_size and
1690 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001691 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001692
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001693 When enabled with the default parameters, this option has
1694 almost no overhead, as it reserves a relatively small amount
1695 of memory and scans it infrequently. It both detects corruption
1696 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001697
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001698 It is, however, intended as a diagnostic tool; if repeatable
1699 BIOS-originated corruption always affects the same memory,
1700 you can use memmap= to prevent the kernel from using that
1701 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001702
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001703config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001704 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001705 depends on X86_CHECK_BIOS_CORRUPTION
1706 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001707 ---help---
1708 Set whether the default state of memory_corruption_check is
1709 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001710
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001711config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001712 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1713 default 64
1714 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001715 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001716 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001717
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001718 The first page contains BIOS data structures that the kernel
1719 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001720
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001721 By default we reserve the first 64K of physical RAM, as a
1722 number of BIOSes are known to corrupt that memory range
1723 during events such as suspend/resume or monitor cable
1724 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001725
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001726 You can set this to 4 if you are absolutely sure that you
1727 trust the BIOS to get all its memory reservations and usages
1728 right. If you know your BIOS have problems beyond the
1729 default 64K area, you can set this to 640 to avoid using the
1730 entire low memory range.
1731
1732 If you have doubts about the BIOS (e.g. suspend/resume does
1733 not work or there's kernel crashes after certain hardware
1734 hotplug events) then you might want to enable
1735 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1736 typical corruption patterns.
1737
1738 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001739
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001740config MATH_EMULATION
1741 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001742 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001743 prompt "Math emulation" if X86_32
1744 ---help---
1745 Linux can emulate a math coprocessor (used for floating point
1746 operations) if you don't have one. 486DX and Pentium processors have
1747 a math coprocessor built in, 486SX and 386 do not, unless you added
1748 a 487DX or 387, respectively. (The messages during boot time can
1749 give you some hints here ["man dmesg"].) Everyone needs either a
1750 coprocessor or this emulation.
1751
1752 If you don't have a math coprocessor, you need to say Y here; if you
1753 say Y here even though you have a coprocessor, the coprocessor will
1754 be used nevertheless. (This behavior can be changed with the kernel
1755 command line option "no387", which comes handy if your coprocessor
1756 is broken. Try "man bootparam" or see the documentation of your boot
1757 loader (lilo or loadlin) about how to pass options to the kernel at
1758 boot time.) This means that it is a good idea to say Y here if you
1759 intend to use this kernel on different machines.
1760
1761 More information about the internals of the Linux math coprocessor
1762 emulation can be found in <file:arch/x86/math-emu/README>.
1763
1764 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1765 kernel, it won't hurt.
1766
1767config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001768 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001769 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001770 ---help---
1771 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1772 the Memory Type Range Registers (MTRRs) may be used to control
1773 processor access to memory ranges. This is most useful if you have
1774 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1775 allows bus write transfers to be combined into a larger transfer
1776 before bursting over the PCI/AGP bus. This can increase performance
1777 of image write operations 2.5 times or more. Saying Y here creates a
1778 /proc/mtrr file which may be used to manipulate your processor's
1779 MTRRs. Typically the X server should use this.
1780
1781 This code has a reasonably generic interface so that similar
1782 control registers on other processors can be easily supported
1783 as well:
1784
1785 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1786 Registers (ARRs) which provide a similar functionality to MTRRs. For
1787 these, the ARRs are used to emulate the MTRRs.
1788 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1789 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1790 write-combining. All of these processors are supported by this code
1791 and it makes sense to say Y here if you have one of them.
1792
1793 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1794 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1795 can lead to all sorts of problems, so it's good to say Y here.
1796
1797 You can safely say Y even if your machine doesn't have MTRRs, you'll
1798 just add about 9 KB to your kernel.
1799
Randy Dunlap7225e752008-07-26 17:54:22 -07001800 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001801
Yinghai Lu95ffa242008-04-29 03:52:33 -07001802config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001803 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001804 prompt "MTRR cleanup support"
1805 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001806 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001807 Convert MTRR layout from continuous to discrete, so X drivers can
1808 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001809
Thomas Gleixneraba37282008-07-15 14:48:48 +02001810 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001811 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001812 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001813
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001814 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001815
1816config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001817 int "MTRR cleanup enable value (0-1)"
1818 range 0 1
1819 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001820 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001821 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001822 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001823
Yinghai Lu12031a62008-05-02 02:40:22 -07001824config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1825 int "MTRR cleanup spare reg num (0-7)"
1826 range 0 7
1827 default "1"
1828 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001829 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001830 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001831 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001832
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001833config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001834 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001835 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001836 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001837 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001838 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001839
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001840 PATs are the modern equivalents of MTRRs and are much more
1841 flexible than MTRRs.
1842
1843 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001844 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001845
1846 If unsure, say Y.
1847
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001848config ARCH_USES_PG_UNCACHED
1849 def_bool y
1850 depends on X86_PAT
1851
H. Peter Anvin628c6242011-07-31 13:59:29 -07001852config ARCH_RANDOM
1853 def_bool y
1854 prompt "x86 architectural random number generator" if EXPERT
1855 ---help---
1856 Enable the x86 architectural RDRAND instruction
1857 (Intel Bull Mountain technology) to generate random numbers.
1858 If supported, this is a high bandwidth, cryptographically
1859 secure hardware random number generator.
1860
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001861config X86_SMAP
1862 def_bool y
1863 prompt "Supervisor Mode Access Prevention" if EXPERT
1864 ---help---
1865 Supervisor Mode Access Prevention (SMAP) is a security
1866 feature in newer Intel processors. There is a small
1867 performance cost if this enabled and turned on; there is
1868 also a small increase in the kernel size if this is enabled.
1869
1870 If unsure, say Y.
1871
Ricardo Neriaa35f892017-11-05 18:27:54 -08001872config X86_INTEL_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001873 def_bool y
Ricardo Neriaa35f892017-11-05 18:27:54 -08001874 depends on CPU_SUP_INTEL
1875 prompt "Intel User Mode Instruction Prevention" if EXPERT
1876 ---help---
1877 The User Mode Instruction Prevention (UMIP) is a security
1878 feature in newer Intel processors. If enabled, a general
Ricardo Neri796ebc82017-11-13 22:29:42 -08001879 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1880 or STR instructions are executed in user mode. These instructions
1881 unnecessarily expose information about the hardware state.
1882
1883 The vast majority of applications do not use these instructions.
1884 For the very few that do, software emulation is provided in
1885 specific cases in protected and virtual-8086 modes. Emulated
1886 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001887
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001888config X86_INTEL_MPX
1889 prompt "Intel MPX (Memory Protection Extensions)"
1890 def_bool n
Rik van Rieldf3735c2017-09-06 16:25:11 -07001891 # Note: only available in 64-bit mode due to VMA flags shortage
1892 depends on CPU_SUP_INTEL && X86_64
1893 select ARCH_USES_HIGH_VMA_FLAGS
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001894 ---help---
1895 MPX provides hardware features that can be used in
1896 conjunction with compiler-instrumented code to check
1897 memory references. It is designed to detect buffer
1898 overflow or underflow bugs.
1899
1900 This option enables running applications which are
1901 instrumented or otherwise use MPX. It does not use MPX
1902 itself inside the kernel or to protect the kernel
1903 against bad memory references.
1904
1905 Enabling this option will make the kernel larger:
1906 ~8k of kernel text and 36 bytes of data on a 64-bit
1907 defconfig. It adds a long to the 'mm_struct' which
1908 will increase the kernel memory overhead of each
1909 process and adds some branches to paths used during
1910 exec() and munmap().
1911
1912 For details, see Documentation/x86/intel_mpx.txt
1913
1914 If unsure, say N.
1915
Dave Hansen35e97792016-02-12 13:02:00 -08001916config X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001917 prompt "Intel Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001918 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001919 # Note: only available in 64-bit mode
Dave Hansen35e97792016-02-12 13:02:00 -08001920 depends on CPU_SUP_INTEL && X86_64
Ingo Molnar52c8e602016-11-15 10:15:03 +01001921 select ARCH_USES_HIGH_VMA_FLAGS
1922 select ARCH_HAS_PKEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001923 ---help---
1924 Memory Protection Keys provides a mechanism for enforcing
1925 page-based protections, but without requiring modification of the
1926 page tables when an application changes protection domains.
1927
1928 For details, see Documentation/x86/protection-keys.txt
1929
1930 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001931
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001932config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001933 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001934 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001935 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001936 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001937 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001938 This enables the kernel to use EFI runtime services that are
1939 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001940
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001941 This option is only useful on systems that have EFI firmware.
1942 In addition, you should use the latest ELILO loader available
1943 at <http://elilo.sourceforge.net> in order to take advantage
1944 of EFI runtime services. However, even with this option, the
1945 resultant kernel should continue to boot on existing non-EFI
1946 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001947
Matt Fleming291f3632011-12-12 21:27:52 +00001948config EFI_STUB
1949 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001950 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001951 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001952 ---help---
1953 This kernel feature allows a bzImage to be loaded directly
1954 by EFI firmware without the use of a bootloader.
1955
Roy Franz4172fe22013-09-22 15:45:25 -07001956 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001957
Matt Fleming7d453ee2014-01-10 18:52:06 +00001958config EFI_MIXED
1959 bool "EFI mixed-mode support"
1960 depends on EFI_STUB && X86_64
1961 ---help---
1962 Enabling this feature allows a 64-bit kernel to be booted
1963 on a 32-bit firmware, provided that your CPU supports 64-bit
1964 mode.
1965
1966 Note that it is not possible to boot a mixed-mode enabled
1967 kernel via the EFI boot stub - a bootloader that supports
1968 the EFI handover protocol must be used.
1969
1970 If unsure, say N.
1971
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001972config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001973 def_bool y
1974 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001975 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001976 This kernel feature is useful for number crunching applications
1977 that may need to compute untrusted bytecode during their
1978 execution. By using pipes or other transports made available to
1979 the process as file descriptors supporting the read/write
1980 syscalls, it's possible to isolate those applications in
1981 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001982 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001983 and the task is only allowed to execute a few safe syscalls
1984 defined by each seccomp mode.
1985
1986 If unsure, say Y. Only embedded should say N here.
1987
Masahiro Yamada8636a1f2018-12-11 20:01:04 +09001988source "kernel/Kconfig.hz"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001989
1990config KEXEC
1991 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001992 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001993 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001994 kexec is a system call that implements the ability to shutdown your
1995 current kernel, and to start another kernel. It is like a reboot
1996 but it is independent of the system firmware. And like a reboot
1997 you can start any kernel with it, not just Linux.
1998
1999 The name comes from the similarity to the exec system call.
2000
2001 It is an ongoing process to be certain the hardware in a machine
2002 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02002003 initially work for you. As of this writing the exact hardware
2004 interface is strongly in flux, so no good recommendation can be
2005 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002006
Vivek Goyal74ca3172014-08-29 15:18:46 -07002007config KEXEC_FILE
2008 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07002009 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07002010 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07002011 depends on X86_64
2012 depends on CRYPTO=y
2013 depends on CRYPTO_SHA256=y
2014 ---help---
2015 This is new version of kexec system call. This system call is
2016 file based and takes file descriptors as system call argument
2017 for kernel and initramfs as opposed to list of segments as
2018 accepted by previous system call.
2019
AKASHI Takahirob799a092018-04-13 15:35:45 -07002020config ARCH_HAS_KEXEC_PURGATORY
2021 def_bool KEXEC_FILE
2022
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002023config KEXEC_VERIFY_SIG
2024 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07002025 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002026 ---help---
2027 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002028 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002029
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002030 In addition to that option, you need to enable signature
2031 verification for the corresponding kernel image type being
2032 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002033
2034config KEXEC_BZIMAGE_VERIFY_SIG
2035 bool "Enable bzImage signature verification support"
2036 depends on KEXEC_VERIFY_SIG
2037 depends on SIGNED_PE_FILE_VERIFICATION
2038 select SYSTEM_TRUSTED_KEYRING
2039 ---help---
2040 Enable bzImage signature verification support.
2041
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002042config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002043 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002044 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002045 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002046 Generate crash dump after being started by kexec.
2047 This should be normally only set in special crash dump kernels
2048 which are loaded in the main kernel with kexec-tools into
2049 a specially reserved region and then later executed after
2050 a crash by kdump/kexec. The crash dump kernel must be compiled
2051 to a memory address not used by the main kernel or BIOS using
2052 PHYSICAL_START, or it must be built as a relocatable image
2053 (CONFIG_RELOCATABLE=y).
2054 For more details see Documentation/kdump/kdump.txt
2055
Huang Ying3ab83522008-07-25 19:45:07 -07002056config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002057 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002058 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002059 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07002060 Jump between original kernel and kexeced kernel and invoke
2061 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002062
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002063config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002064 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002065 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002066 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002067 This gives the physical address where the kernel is loaded.
2068
2069 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2070 bzImage will decompress itself to above physical address and
2071 run from there. Otherwise, bzImage will run from the address where
2072 it has been loaded by the boot loader and will ignore above physical
2073 address.
2074
2075 In normal kdump cases one does not have to set/change this option
2076 as now bzImage can be compiled as a completely relocatable image
2077 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2078 address. This option is mainly useful for the folks who don't want
2079 to use a bzImage for capturing the crash dump and want to use a
2080 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2081 to be specifically compiled to run from a specific memory area
2082 (normally a reserved region) and this option comes handy.
2083
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002084 So if you are using bzImage for capturing the crash dump,
2085 leave the value here unchanged to 0x1000000 and set
2086 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2087 for capturing the crash dump change this value to start of
2088 the reserved region. In other words, it can be set based on
2089 the "X" value as specified in the "crashkernel=YM@XM"
2090 command line boot parameter passed to the panic-ed
2091 kernel. Please take a look at Documentation/kdump/kdump.txt
2092 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002093
2094 Usage of bzImage for capturing the crash dump is recommended as
2095 one does not have to build two kernels. Same kernel can be used
2096 as production kernel and capture kernel. Above option should have
2097 gone away after relocatable bzImage support is introduced. But it
2098 is present because there are users out there who continue to use
2099 vmlinux for dump capture. This option should go away down the
2100 line.
2101
2102 Don't change this unless you know what you are doing.
2103
2104config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002105 bool "Build a relocatable kernel"
2106 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002107 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002108 This builds a kernel image that retains relocation information
2109 so it can be loaded someplace besides the default 1MB.
2110 The relocations tend to make the kernel binary about 10% larger,
2111 but are discarded at runtime.
2112
2113 One use is for the kexec on panic case where the recovery kernel
2114 must live at a different physical address than the primary
2115 kernel.
2116
2117 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2118 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002119 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002120
Kees Cook8ab38202013-10-10 17:18:14 -07002121config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002122 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002123 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002124 default y
Kees Cook8ab38202013-10-10 17:18:14 -07002125 ---help---
Baoquan Hee8581e32016-04-20 13:55:43 -07002126 In support of Kernel Address Space Layout Randomization (KASLR),
2127 this randomizes the physical address at which the kernel image
2128 is decompressed and the virtual address where the kernel
2129 image is mapped, as a security feature that deters exploit
2130 attempts relying on knowledge of the location of kernel
2131 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002132
Kees Cooked9f0072016-05-25 15:45:33 -07002133 On 64-bit, the kernel physical and virtual addresses are
2134 randomized separately. The physical address will be anywhere
2135 between 16MB and the top of physical memory (up to 64TB). The
2136 virtual address will be randomized from 16MB up to 1GB (9 bits
2137 of entropy). Note that this also reduces the memory space
2138 available to kernel modules from 1.5GB to 1GB.
2139
2140 On 32-bit, the kernel physical and virtual addresses are
2141 randomized together. They will be randomized from 16MB up to
2142 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002143
Baoquan Hee8581e32016-04-20 13:55:43 -07002144 Entropy is generated using the RDRAND instruction if it is
2145 supported. If RDTSC is supported, its value is mixed into
2146 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002147 supported, then entropy is read from the i8254 timer. The
2148 usable entropy is limited by the kernel being built using
2149 2GB addressing, and that PHYSICAL_ALIGN must be at a
2150 minimum of 2MB. As a result, only 10 bits of entropy are
2151 theoretically possible, but the implementations are further
2152 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002153
Ingo Molnar6807c842017-04-18 11:08:12 +02002154 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002155
2156# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002157config X86_NEED_RELOCS
2158 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002159 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002160
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002161config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002162 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002163 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002164 range 0x2000 0x1000000 if X86_32
2165 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002166 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002167 This value puts the alignment restrictions on physical address
2168 where kernel is loaded and run from. Kernel is compiled for an
2169 address which meets above alignment restriction.
2170
2171 If bootloader loads the kernel at a non-aligned address and
2172 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2173 address aligned to above value and run from there.
2174
2175 If bootloader loads the kernel at a non-aligned address and
2176 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2177 load address and decompress itself to the address it has been
2178 compiled for and run from there. The address for which kernel is
2179 compiled already meets above alignment restrictions. Hence the
2180 end result is that kernel runs from a physical address meeting
2181 above alignment restrictions.
2182
Kees Cooka0215062013-07-08 09:15:17 -07002183 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2184 this value must be a multiple of 0x200000.
2185
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002186 Don't change this unless you know what you are doing.
2187
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002188config DYNAMIC_MEMORY_LAYOUT
2189 bool
2190 ---help---
2191 This option makes base addresses of vmalloc and vmemmap as well as
2192 __PAGE_OFFSET movable during boot.
2193
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002194config RANDOMIZE_MEMORY
2195 bool "Randomize the kernel memory sections"
2196 depends on X86_64
2197 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002198 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002199 default RANDOMIZE_BASE
2200 ---help---
2201 Randomizes the base virtual address of kernel memory sections
2202 (physical memory mapping, vmalloc & vmemmap). This security feature
2203 makes exploits relying on predictable memory locations less reliable.
2204
2205 The order of allocations remains unchanged. Entropy is generated in
2206 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2207 configuration have in average 30,000 different possible virtual
2208 addresses for each memory section.
2209
Ingo Molnar6807c842017-04-18 11:08:12 +02002210 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002211
Thomas Garnier90397a42016-06-21 17:47:06 -07002212config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2213 hex "Physical memory mapping padding" if EXPERT
2214 depends on RANDOMIZE_MEMORY
2215 default "0xa" if MEMORY_HOTPLUG
2216 default "0x0"
2217 range 0x1 0x40 if MEMORY_HOTPLUG
2218 range 0x0 0x40
2219 ---help---
2220 Define the padding in terabytes added to the existing physical
2221 memory size during kernel memory randomization. It is useful
2222 for memory hotplug support but reduces the entropy available for
2223 address randomization.
2224
2225 If unsure, leave at the default value.
2226
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002227config HOTPLUG_CPU
Thomas Gleixnerbebd0242019-03-26 17:36:06 +01002228 def_bool y
Stephen Rothwell40b31362013-05-21 13:49:35 +10002229 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002230
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002231config BOOTPARAM_HOTPLUG_CPU0
2232 bool "Set default setting of cpu0_hotpluggable"
Kees Cook2c922cd2013-01-22 13:01:19 -08002233 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002234 ---help---
2235 Set whether default state of cpu0_hotpluggable is on or off.
2236
2237 Say Y here to enable CPU0 hotplug by default. If this switch
2238 is turned on, there is no need to give cpu0_hotplug kernel
2239 parameter and the CPU0 hotplug feature is enabled by default.
2240
2241 Please note: there are two known CPU0 dependencies if you want
2242 to enable the CPU0 hotplug feature either by this switch or by
2243 cpu0_hotplug kernel parameter.
2244
2245 First, resume from hibernate or suspend always starts from CPU0.
2246 So hibernate and suspend are prevented if CPU0 is offline.
2247
2248 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2249 offline if any interrupt can not migrate out of CPU0. There may
2250 be other CPU0 dependencies.
2251
2252 Please make sure the dependencies are under your control before
2253 you enable this feature.
2254
2255 Say N if you don't want to enable CPU0 hotplug feature by default.
2256 You still can enable the CPU0 hotplug feature at boot by kernel
2257 parameter cpu0_hotplug.
2258
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002259config DEBUG_HOTPLUG_CPU0
2260 def_bool n
2261 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002262 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002263 ---help---
2264 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2265 soon as possible and boots up userspace with CPU0 offlined. User
2266 can online CPU0 back after boot time.
2267
2268 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2269 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2270 compilation or giving cpu0_hotplug kernel parameter at boot.
2271
2272 If unsure, say N.
2273
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002274config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002275 def_bool n
2276 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002277 depends on COMPAT_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002278 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002279 Certain buggy versions of glibc will crash if they are
2280 presented with a 32-bit vDSO that is not mapped at the address
2281 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002282
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002283 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2284 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2285 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2286 the only released version with the bug, but OpenSUSE 9
2287 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002288
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002289 The symptom of the bug is that everything crashes on startup, saying:
2290 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2291
2292 Saying Y here changes the default value of the vdso32 boot
2293 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2294 This works around the glibc bug but hurts performance.
2295
2296 If unsure, say N: if you are compiling your own kernel, you
2297 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002298
Kees Cook3dc33bd2015-08-12 17:55:19 -07002299choice
2300 prompt "vsyscall table for legacy applications"
2301 depends on X86_64
2302 default LEGACY_VSYSCALL_EMULATE
2303 help
2304 Legacy user code that does not know how to find the vDSO expects
2305 to be able to issue three syscalls by calling fixed addresses in
2306 kernel space. Since this location is not randomized with ASLR,
2307 it can be used to assist security vulnerability exploitation.
2308
2309 This setting can be changed at boot time via the kernel command
Andy Lutomirski076ca272018-03-07 11:12:27 -08002310 line parameter vsyscall=[emulate|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002311
2312 On a system with recent enough glibc (2.14 or newer) and no
2313 static binaries, you can say None without a performance penalty
2314 to improve security.
2315
2316 If unsure, select "Emulate".
2317
Kees Cook3dc33bd2015-08-12 17:55:19 -07002318 config LEGACY_VSYSCALL_EMULATE
2319 bool "Emulate"
2320 help
2321 The kernel traps and emulates calls into the fixed
2322 vsyscall address mapping. This makes the mapping
2323 non-executable, but it still contains known contents,
2324 which could be used in certain rare security vulnerability
2325 exploits. This configuration is recommended when userspace
2326 still uses the vsyscall area.
2327
2328 config LEGACY_VSYSCALL_NONE
2329 bool "None"
2330 help
2331 There will be no vsyscall mapping at all. This will
2332 eliminate any risk of ASLR bypass due to the vsyscall
2333 fixed address mapping. Attempts to use the vsyscalls
2334 will be reported to dmesg, so that either old or
2335 malicious userspace programs can be identified.
2336
2337endchoice
2338
Tim Bird516cbf32008-08-12 12:52:36 -07002339config CMDLINE_BOOL
2340 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002341 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002342 Allow for specifying boot arguments to the kernel at
2343 build time. On some systems (e.g. embedded ones), it is
2344 necessary or convenient to provide some or all of the
2345 kernel boot arguments with the kernel itself (that is,
2346 to not rely on the boot loader to provide them.)
2347
2348 To compile command line arguments into the kernel,
2349 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002350 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002351
2352 Systems with fully functional boot loaders (i.e. non-embedded)
2353 should leave this option set to 'N'.
2354
2355config CMDLINE
2356 string "Built-in kernel command string"
2357 depends on CMDLINE_BOOL
2358 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002359 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002360 Enter arguments here that should be compiled into the kernel
2361 image and used at boot time. If the boot loader provides a
2362 command line at boot time, it is appended to this string to
2363 form the full kernel command line, when the system boots.
2364
2365 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2366 change this behavior.
2367
2368 In most cases, the command line (whether built-in or provided
2369 by the boot loader) should specify the device for the root
2370 file system.
2371
2372config CMDLINE_OVERRIDE
2373 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002374 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002375 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002376 Set this option to 'Y' to have the kernel ignore the boot loader
2377 command line, and use ONLY the built-in command line.
2378
2379 This is used to work around broken boot loaders. This should
2380 be set to 'N' under normal conditions.
2381
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002382config MODIFY_LDT_SYSCALL
2383 bool "Enable the LDT (local descriptor table)" if EXPERT
2384 default y
2385 ---help---
2386 Linux can allow user programs to install a per-process x86
2387 Local Descriptor Table (LDT) using the modify_ldt(2) system
2388 call. This is required to run 16-bit or segmented code such as
2389 DOSEMU or some Wine programs. It is also used by some very old
2390 threading libraries.
2391
2392 Enabling this feature adds a small amount of overhead to
2393 context switches and increases the low-level kernel attack
2394 surface. Disabling it removes the modify_ldt(2) system call.
2395
2396 Saying 'N' here may make sense for embedded or server kernels.
2397
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002398source "kernel/livepatch/Kconfig"
2399
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002400endmenu
2401
Michal Hocko3072e412017-09-08 16:11:39 -07002402config ARCH_HAS_ADD_PAGES
2403 def_bool y
2404 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2405
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002406config ARCH_ENABLE_MEMORY_HOTPLUG
2407 def_bool y
2408 depends on X86_64 || (X86_32 && HIGHMEM)
2409
Gary Hade35551052008-10-31 10:52:03 -07002410config ARCH_ENABLE_MEMORY_HOTREMOVE
2411 def_bool y
2412 depends on MEMORY_HOTPLUG
2413
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002414config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002415 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002416 depends on NUMA
2417
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002418config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2419 def_bool y
2420 depends on X86_64 || X86_PAE
2421
Naoya Horiguchic177c812014-06-04 16:05:35 -07002422config ARCH_ENABLE_HUGEPAGE_MIGRATION
2423 def_bool y
2424 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2425
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002426config ARCH_ENABLE_THP_MIGRATION
2427 def_bool y
2428 depends on X86_64 && TRANSPARENT_HUGEPAGE
2429
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002430menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002431
2432config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002433 def_bool y
Zhimin Gu44556532018-09-21 14:27:29 +08002434 depends on HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002435
2436source "kernel/power/Kconfig"
2437
2438source "drivers/acpi/Kconfig"
2439
Feng Tangefafc8b2009-08-14 15:23:29 -04002440source "drivers/sfi/Kconfig"
2441
Andi Kleena6b68072008-01-30 13:32:49 +01002442config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002443 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002444 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002445
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002446menuconfig APM
2447 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002448 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002449 ---help---
2450 APM is a BIOS specification for saving power using several different
2451 techniques. This is mostly useful for battery powered laptops with
2452 APM compliant BIOSes. If you say Y here, the system time will be
2453 reset after a RESUME operation, the /proc/apm device will provide
2454 battery status information, and user-space programs will receive
2455 notification of APM "events" (e.g. battery status change).
2456
2457 If you select "Y" here, you can disable actual use of the APM
2458 BIOS by passing the "apm=off" option to the kernel at boot time.
2459
2460 Note that the APM support is almost completely disabled for
2461 machines with more than one CPU.
2462
2463 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002464 and more information, read <file:Documentation/power/apm-acpi.txt>
2465 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002466 <http://www.tldp.org/docs.html#howto>.
2467
2468 This driver does not spin down disk drives (see the hdparm(8)
2469 manpage ("man 8 hdparm") for that), and it doesn't turn off
2470 VESA-compliant "green" monitors.
2471
2472 This driver does not support the TI 4000M TravelMate and the ACER
2473 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2474 desktop machines also don't have compliant BIOSes, and this driver
2475 may cause those machines to panic during the boot phase.
2476
2477 Generally, if you don't have a battery in your machine, there isn't
2478 much point in using this driver and you should say N. If you get
2479 random kernel OOPSes or reboots that don't seem to be related to
2480 anything, try disabling/enabling this option (or disabling/enabling
2481 APM in your BIOS).
2482
2483 Some other things you should try when experiencing seemingly random,
2484 "weird" problems:
2485
2486 1) make sure that you have enough swap space and that it is
2487 enabled.
2488 2) pass the "no-hlt" option to the kernel
2489 3) switch on floating point emulation in the kernel and pass
2490 the "no387" option to the kernel
2491 4) pass the "floppy=nodma" option to the kernel
2492 5) pass the "mem=4M" option to the kernel (thereby disabling
2493 all but the first 4 MB of RAM)
2494 6) make sure that the CPU is not over clocked.
2495 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2496 8) disable the cache from your BIOS settings
2497 9) install a fan for the video card or exchange video RAM
2498 10) install a better fan for the CPU
2499 11) exchange RAM chips
2500 12) exchange the motherboard.
2501
2502 To compile this driver as a module, choose M here: the
2503 module will be called apm.
2504
2505if APM
2506
2507config APM_IGNORE_USER_SUSPEND
2508 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002509 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002510 This option will ignore USER SUSPEND requests. On machines with a
2511 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2512 series notebooks, it is necessary to say Y because of a BIOS bug.
2513
2514config APM_DO_ENABLE
2515 bool "Enable PM at boot time"
2516 ---help---
2517 Enable APM features at boot time. From page 36 of the APM BIOS
2518 specification: "When disabled, the APM BIOS does not automatically
2519 power manage devices, enter the Standby State, enter the Suspend
2520 State, or take power saving steps in response to CPU Idle calls."
2521 This driver will make CPU Idle calls when Linux is idle (unless this
2522 feature is turned off -- see "Do CPU IDLE calls", below). This
2523 should always save battery power, but more complicated APM features
2524 will be dependent on your BIOS implementation. You may need to turn
2525 this option off if your computer hangs at boot time when using APM
2526 support, or if it beeps continuously instead of suspending. Turn
2527 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2528 T400CDT. This is off by default since most machines do fine without
2529 this feature.
2530
2531config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002532 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002533 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002534 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002535 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2536 On some machines, this can activate improved power savings, such as
2537 a slowed CPU clock rate, when the machine is idle. These idle calls
2538 are made after the idle loop has run for some length of time (e.g.,
2539 333 mS). On some machines, this will cause a hang at boot time or
2540 whenever the CPU becomes idle. (On machines with more than one CPU,
2541 this option does nothing.)
2542
2543config APM_DISPLAY_BLANK
2544 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002545 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002546 Enable console blanking using the APM. Some laptops can use this to
2547 turn off the LCD backlight when the screen blanker of the Linux
2548 virtual console blanks the screen. Note that this is only used by
2549 the virtual console screen blanker, and won't turn off the backlight
2550 when using the X Window system. This also doesn't have anything to
2551 do with your VESA-compliant power-saving monitor. Further, this
2552 option doesn't work for all laptops -- it might not turn off your
2553 backlight at all, or it might print a lot of errors to the console,
2554 especially if you are using gpm.
2555
2556config APM_ALLOW_INTS
2557 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002558 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002559 Normally we disable external interrupts while we are making calls to
2560 the APM BIOS as a measure to lessen the effects of a badly behaving
2561 BIOS implementation. The BIOS should reenable interrupts if it
2562 needs to. Unfortunately, some BIOSes do not -- especially those in
2563 many of the newer IBM Thinkpads. If you experience hangs when you
2564 suspend, try setting this to Y. Otherwise, say N.
2565
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002566endif # APM
2567
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002568source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002569
2570source "drivers/cpuidle/Kconfig"
2571
Andy Henroid27471fd2008-10-09 11:45:22 -07002572source "drivers/idle/Kconfig"
2573
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002574endmenu
2575
2576
2577menu "Bus options (PCI etc.)"
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
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002640config MMCONF_FAM10H
2641 def_bool y
2642 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002643
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002644config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002645 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002646 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002647 help
2648 Read the PCI windows out of the CNB20LE host bridge. This allows
2649 PCI hotplug to work on systems with the CNB20LE chipset which do
2650 not have ACPI.
2651
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002652 There's no public spec for this chipset, and this functionality
2653 is known to be incomplete.
2654
2655 You should say N unless you know you need this.
2656
William Breathitt Gray3a495512016-05-27 18:08:27 -04002657config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002658 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002659 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002660 Expose ISA bus device drivers and options available for selection and
2661 configuration. Enable this option if your target machine has an ISA
2662 bus. ISA is an older system, displaced by PCI and newer bus
2663 architectures -- if your target machine is modern, it probably does
2664 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002665
2666 If unsure, say N.
2667
David Rientjes1c00f012011-03-22 16:34:59 -07002668# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002669config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002670 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2671 default y
2672 help
2673 Enables ISA-style DMA support for devices requiring such controllers.
2674 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002675
Linus Torvalds51e68d02016-05-21 10:25:19 -07002676if X86_32
2677
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002678config ISA
2679 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002680 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002681 Find out whether you have ISA slots on your motherboard. ISA is the
2682 name of a bus system, i.e. the way the CPU talks to the other stuff
2683 inside your box. Other bus systems are PCI, EISA, MicroChannel
2684 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2685 newer boards don't support it. If you have ISA, say Y, otherwise N.
2686
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002687config SCx200
2688 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002689 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002690 This provides basic support for National Semiconductor's
2691 (now AMD's) Geode processors. The driver probes for the
2692 PCI-IDs of several on-chip devices, so its a good dependency
2693 for other scx200_* drivers.
2694
2695 If compiled as a module, the driver is named scx200.
2696
2697config SCx200HR_TIMER
2698 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002699 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002700 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002701 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002702 This driver provides a clocksource built upon the on-chip
2703 27MHz high-resolution timer. Its also a workaround for
2704 NSC Geode SC-1100's buggy TSC, which loses time when the
2705 processor goes idle (as is done by the scheduler). The
2706 other workaround is idle=poll boot option.
2707
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002708config OLPC
2709 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002710 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002711 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002712 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002713 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002714 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002715 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002716 Add support for detecting the unique features of the OLPC
2717 XO hardware.
2718
Daniel Drakea3128582011-06-25 17:34:10 +01002719config OLPC_XO1_PM
2720 bool "OLPC XO-1 Power Management"
Borislav Petkovfa112cf2018-10-05 15:13:07 +02002721 depends on OLPC && MFD_CS5535=y && PM_SLEEP
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002722 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002723 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002724
Daniel Drakecfee9592011-06-25 17:34:17 +01002725config OLPC_XO1_RTC
2726 bool "OLPC XO-1 Real Time Clock"
2727 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2728 ---help---
2729 Add support for the XO-1 real time clock, which can be used as a
2730 programmable wakeup source.
2731
Daniel Drake7feda8e2011-06-25 17:34:12 +01002732config OLPC_XO1_SCI
2733 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002734 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002735 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002736 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002737 ---help---
2738 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002739 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002740 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002741 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002742 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002743 - AC adapter status updates
2744 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002745
Daniel Drakea0f30f52011-06-25 17:34:18 +01002746config OLPC_XO15_SCI
2747 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002748 depends on OLPC && ACPI
2749 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002750 ---help---
2751 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2752 - EC-driven system wakeups
2753 - AC adapter status updates
2754 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002755
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002756config ALIX
2757 bool "PCEngines ALIX System Support (LED setup)"
2758 select GPIOLIB
2759 ---help---
2760 This option enables system support for the PCEngines ALIX.
2761 At present this just sets up LEDs for GPIO control on
2762 ALIX2/3/6 boards. However, other system specific setup should
2763 get added here.
2764
2765 Note: You must still enable the drivers for GPIO and LED support
2766 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2767
2768 Note: You have to set alix.force=1 for boards with Award BIOS.
2769
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002770config NET5501
2771 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2772 select GPIOLIB
2773 ---help---
2774 This option enables system support for the Soekris Engineering net5501.
2775
Philip A. Prindeville31970592012-01-14 01:45:39 -07002776config GEOS
2777 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2778 select GPIOLIB
2779 depends on DMI
2780 ---help---
2781 This option enables system support for the Traverse Technologies GEOS.
2782
Vivien Didelot7d029122013-01-04 16:18:14 -05002783config TS5500
2784 bool "Technologic Systems TS-5500 platform support"
2785 depends on MELAN
2786 select CHECK_SIGNATURE
2787 select NEW_LEDS
2788 select LEDS_CLASS
2789 ---help---
2790 This option enables system support for the Technologic Systems TS-5500.
2791
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002792endif # X86_32
2793
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002794config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002795 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002796 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002797
David Herrmanne3263ab2013-08-02 14:05:22 +02002798config X86_SYSFB
2799 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2800 help
2801 Firmwares often provide initial graphics framebuffers so the BIOS,
2802 bootloader or kernel can show basic video-output during boot for
2803 user-guidance and debugging. Historically, x86 used the VESA BIOS
2804 Extensions and EFI-framebuffers for this, which are mostly limited
2805 to x86.
2806 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2807 framebuffers so the new generic system-framebuffer drivers can be
2808 used on x86. If the framebuffer is not compatible with the generic
Nikolas Nybye3a5dc02018-08-25 19:10:54 -04002809 modes, it is advertised as fallback platform framebuffer so legacy
David Herrmanne3263ab2013-08-02 14:05:22 +02002810 drivers like efifb, vesafb and uvesafb can pick it up.
2811 If this option is not selected, all system framebuffers are always
2812 marked as fallback platform framebuffers as usual.
2813
2814 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2815 not be able to pick up generic system framebuffers if this option
2816 is selected. You are highly encouraged to enable simplefb as
2817 replacement if you select this option. simplefb can correctly deal
2818 with generic system framebuffers. But you should still keep vesafb
2819 and others enabled as fallback if a system framebuffer is
2820 incompatible with simplefb.
2821
2822 If unsure, say Y.
2823
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002824endmenu
2825
2826
Christoph Hellwig15724972018-07-31 13:39:30 +02002827menu "Binary Emulations"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002828
2829config IA32_EMULATION
2830 bool "IA32 Emulation"
2831 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002832 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002833 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002834 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002835 select COMPAT_OLD_SIGACTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002836 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002837 Include code to run legacy 32-bit programs under a
2838 64-bit kernel. You should likely turn this on, unless you're
2839 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002840
2841config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002842 tristate "IA32 a.out support"
2843 depends on IA32_EMULATION
Borislav Petkoveac61652019-03-05 15:47:51 +01002844 depends on BROKEN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002845 ---help---
2846 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002847
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002848config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002849 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002850 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002851 ---help---
2852 Include code to run binaries for the x32 native 32-bit ABI
2853 for 64-bit processors. An x32 process gets access to the
2854 full 64-bit register file and wide data path while leaving
2855 pointers at 32 bits for smaller memory footprint.
2856
2857 You will need a recent binutils (2.22 or later) with
2858 elf32_x86_64 support enabled to compile a kernel with this
2859 option set.
2860
Ingo Molnar953fee12016-11-15 10:22:52 +01002861config COMPAT_32
2862 def_bool y
2863 depends on IA32_EMULATION || X86_32
2864 select HAVE_UID16
2865 select OLD_SIGSUSPEND3
2866
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002867config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002868 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002869 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002870
Jan Beulich3120e252012-09-10 12:41:45 +01002871if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002872config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002873 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002874
2875config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002876 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002877 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002878endif
David Howellsee009e4a02011-03-07 15:06:20 +00002879
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002880endmenu
2881
2882
Keith Packarde5beae12008-11-03 18:21:45 +01002883config HAVE_ATOMIC_IOMAP
2884 def_bool y
2885 depends on X86_32
2886
Alessandro Rubini4692d772012-04-04 19:39:58 +02002887config X86_DEV_DMA_OPS
2888 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002889 depends on X86_64 || STA2X11
Alessandro Rubini4692d772012-04-04 19:39:58 +02002890
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002891config X86_DMA_REMAP
2892 bool
Alessandro Rubini83125a32012-04-04 19:40:21 +02002893 depends on STA2X11
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002894
Kirill A. Shutemove5855132017-06-06 14:31:20 +03002895config HAVE_GENERIC_GUP
2896 def_bool y
2897
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002898source "drivers/firmware/Kconfig"
2899
Avi Kivityedf88412007-12-16 11:02:48 +02002900source "arch/x86/kvm/Kconfig"