blob: 06027809c59990153f14d57b29a7cee11dc4ea00 [file] [log] [blame]
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
Thomas Gleixner117ed452019-04-14 18:00:08 +020017 select HAVE_DEBUG_STACKOVERFLOW
Ingo Molnar341c7872016-11-15 10:04:55 +010018 select MODULES_USE_ELF_REL
19 select OLD_SIGACTION
Vincenzo Frascino7ac87072019-06-21 10:52:49 +010020 select GENERIC_VDSO_32
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +010021
22config X86_64
Jan Beulich3120e252012-09-10 12:41:45 +010023 def_bool y
24 depends on 64BIT
Ingo Molnard94e0682016-11-15 10:11:57 +010025 # Options that are inherently 64-bit kernel only:
Alexandre Ghiti4eb07162019-05-13 17:19:04 -070026 select ARCH_HAS_GIGANTIC_PAGE
Ingo Molnard94e0682016-11-15 10:11:57 +010027 select ARCH_SUPPORTS_INT128
28 select ARCH_USE_CMPXCHG_LOCKREF
29 select HAVE_ARCH_SOFT_DIRTY
30 select MODULES_USE_ELF_RELA
Christoph Hellwigf616ab52018-05-09 06:53:49 +020031 select NEED_DMA_MAP_STATE
Christoph Hellwig09230cb2018-04-24 09:00:54 +020032 select SWIOTLB
Dominik Brodowskif8781c42018-04-05 11:53:05 +020033 select ARCH_HAS_SYSCALL_WRAPPER
Sam Ravnborg1032c0b2007-11-06 21:35:08 +010034
Steven Rostedt (VMware)518049d2019-05-10 12:05:46 -040035config FORCE_DYNAMIC_FTRACE
36 def_bool y
37 depends on X86_32
38 depends on FUNCTION_TRACER
39 select DYNAMIC_FTRACE
40 help
41 We keep the static function tracing (!DYNAMIC_FTRACE) around
42 in order to test the non static function tracing in the
43 generic code, as other architectures still use it. But we
44 only need to keep it around for x86_64. No need to keep it
45 for x86_32. For x86_32, force DYNAMIC_FTRACE.
Ingo Molnard94e0682016-11-15 10:11:57 +010046#
47# Arch settings
48#
49# ( Note that options that are marked 'if X86_64' could in principle be
50# ported to 32-bit as well. )
51#
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +010052config X86
Harvey Harrison3c2362e2008-01-30 13:31:03 +010053 def_bool y
Ingo Molnarc763ea22016-11-15 10:26:39 +010054 #
55 # Note: keep this list sorted alphabetically
56 #
Ingo Molnar6471b822015-06-03 10:00:13 +020057 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
58 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
Yury Norov942fa982018-05-16 11:18:49 +030059 select ARCH_32BIT_OFF_T if X86_32
Ingo Molnar6471b822015-06-03 10:00:13 +020060 select ARCH_CLOCKSOURCE_DATA
Thomas Gleixner2a21ad52018-09-17 14:45:35 +020061 select ARCH_CLOCKSOURCE_INIT
Ingo Molnarc763ea22016-11-15 10:26:39 +010062 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
Laura Abbottfa5b6ec2017-01-10 13:35:40 -080063 select ARCH_HAS_DEBUG_VIRTUAL
Dan Williams21266be2015-11-19 18:19:29 -080064 select ARCH_HAS_DEVMEM_IS_ALLOWED
Ingo Molnar6471b822015-06-03 10:00:13 +020065 select ARCH_HAS_ELF_RANDOMIZE
Linus Torvalds72d93102014-09-13 11:14:53 -070066 select ARCH_HAS_FAST_MULTIPLIER
Dave Hansen316d0972018-04-20 15:20:28 -070067 select ARCH_HAS_FILTER_PGPROT
Daniel Micay6974f0c2017-07-12 14:36:10 -070068 select ARCH_HAS_FORTIFY_SOURCE
Riku Voipio957e3fa2014-12-12 16:57:44 -080069 select ARCH_HAS_GCOV_PROFILE_ALL
Dmitry Vyukov5c9a8752016-03-22 14:27:30 -070070 select ARCH_HAS_KCOV if X86_64
Thiago Jung Bauermann0c9c1d52019-08-06 01:49:14 -030071 select ARCH_HAS_MEM_ENCRYPT
Mathieu Desnoyers10bcc802018-01-29 15:20:18 -050072 select ARCH_HAS_MEMBARRIER_SYNC_CORE
Ingo Molnarc763ea22016-11-15 10:26:39 +010073 select ARCH_HAS_PMEM_API if X86_64
Robin Murphy17596732019-07-16 16:30:47 -070074 select ARCH_HAS_PTE_DEVMAP if X86_64
Laurent Dufour3010a5e2018-06-07 17:06:08 -070075 select ARCH_HAS_PTE_SPECIAL
Kees Cook39208aa2017-09-02 13:09:46 -070076 select ARCH_HAS_REFCOUNT
Dan Williams0aed55a2017-05-29 12:22:50 -070077 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Dan Williams092b31a2018-07-08 13:46:17 -070078 select ARCH_HAS_UACCESS_MCSAFE if X86_64 && X86_MCE
Daniel Borkmannd2852a22017-02-21 16:09:33 +010079 select ARCH_HAS_SET_MEMORY
Rick Edgecombed253ca02019-04-25 17:11:34 -070080 select ARCH_HAS_SET_DIRECT_MAP
Laura Abbottad21fc42017-02-06 16:31:57 -080081 select ARCH_HAS_STRICT_KERNEL_RWX
82 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050083 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Andrey Ryabininc6d30852016-01-20 15:00:55 -080084 select ARCH_HAS_UBSAN_SANITIZE_ALL
Ingo Molnar6471b822015-06-03 10:00:13 +020085 select ARCH_HAVE_NMI_SAFE_CMPXCHG
86 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040087 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080088 select ARCH_MIGHT_HAVE_PC_SERIO
Thomas Gleixner3599fe12019-04-25 11:45:22 +020089 select ARCH_STACKWALK
Arnd Bergmann2c870e62018-07-24 11:48:45 +020090 select ARCH_SUPPORTS_ACPI
Ingo Molnar6471b822015-06-03 10:00:13 +020091 select ARCH_SUPPORTS_ATOMIC_RMW
Ingo Molnar6471b822015-06-03 10:00:13 +020092 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
93 select ARCH_USE_BUILTIN_BSWAP
Ingo Molnar6471b822015-06-03 10:00:13 +020094 select ARCH_USE_QUEUED_RWLOCKS
95 select ARCH_USE_QUEUED_SPINLOCKS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -070096 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Ingo Molnarc763ea22016-11-15 10:26:39 +010097 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Alexandre Ghiti3876d4a2019-06-27 15:00:11 -070098 select ARCH_WANT_HUGE_PMD_SHARE
Huang Ying38d8b4e2017-07-06 15:37:18 -070099 select ARCH_WANTS_THP_SWAP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200100 select BUILDTIME_EXTABLE_SORT
101 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +0200102 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
103 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +0200104 select DCACHE_WORD_ACCESS
Linus Torvalds45471cd2015-06-24 19:52:06 -0700105 select EDAC_ATOMIC_SCRUB
106 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +0200107 select GENERIC_CLOCKEVENTS
108 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
109 select GENERIC_CLOCKEVENTS_MIN_ADJUST
110 select GENERIC_CMOS_UPDATE
111 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +0100112 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +0200113 select GENERIC_EARLY_IOREMAP
114 select GENERIC_FIND_FIRST_BIT
115 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +0200116 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +0200117 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +0200118 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200119 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200120 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200121 select GENERIC_IRQ_SHOW
122 select GENERIC_PENDING_IRQ if SMP
123 select GENERIC_SMP_IDLE_THREAD
124 select GENERIC_STRNCPY_FROM_USER
125 select GENERIC_STRNLEN_USER
126 select GENERIC_TIME_VSYSCALL
Vincenzo Frascino7ac87072019-06-21 10:52:49 +0100127 select GENERIC_GETTIMEOFDAY
Christoph Hellwig39656e82019-07-11 20:56:49 -0700128 select GUP_GET_PTE_LOW_HIGH if X86_PAE
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200129 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200130 select HAVE_ACPI_APEI if ACPI
131 select HAVE_ACPI_APEI_NMI if ACPI
132 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200133 select HAVE_ARCH_AUDITSYSCALL
134 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
135 select HAVE_ARCH_JUMP_LABEL
Ard Biesheuvelb34006c2018-09-18 23:51:41 -0700136 select HAVE_ARCH_JUMP_LABEL_RELATIVE
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800137 select HAVE_ARCH_KASAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200138 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800139 select HAVE_ARCH_MMAP_RND_BITS if MMU
140 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300141 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ard Biesheuvel271ca782018-08-21 21:56:00 -0700142 select HAVE_ARCH_PREL32_RELOCATIONS
Ingo Molnar6471b822015-06-03 10:00:13 +0200143 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700144 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Alexander Popovafaef012018-08-17 01:16:58 +0300145 select HAVE_ARCH_STACKLEAK
Ingo Molnar6471b822015-06-03 10:00:13 +0200146 select HAVE_ARCH_TRACEHOOK
147 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Matthew Wilcoxa00cc7d2017-02-24 14:57:02 -0800148 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
Andy Lutomirskie37e43a2016-08-11 02:35:23 -0700149 select HAVE_ARCH_VMAP_STACK if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100150 select HAVE_ARCH_WITHIN_STACK_FRAMES
Ingo Molnar6471b822015-06-03 10:00:13 +0200151 select HAVE_CMPXCHG_DOUBLE
152 select HAVE_CMPXCHG_LOCAL
153 select HAVE_CONTEXT_TRACKING if X86_64
Josh Triplettc1bd55f2015-06-30 15:00:00 -0700154 select HAVE_COPY_THREAD_TLS
Ingo Molnar6471b822015-06-03 10:00:13 +0200155 select HAVE_C_RECORDMCOUNT
156 select HAVE_DEBUG_KMEMLEAK
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700157 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400158 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900159 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Wang YanQing03f57812018-05-03 14:10:43 +0800160 select HAVE_EBPF_JIT
Johannes Berg58340a02008-07-25 01:45:33 -0700161 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Christoph Hellwig6630a8e2018-11-15 20:05:37 +0100162 select HAVE_EISA
Jiri Slaby5f56a5d2016-05-20 17:00:16 -0700163 select HAVE_EXIT_THREAD
Christoph Hellwig67a929e2019-07-11 20:57:14 -0700164 select HAVE_FAST_GUP
Steven Rostedt (VMware)644e0e82017-03-23 10:33:52 -0400165 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
Ingo Molnar6471b822015-06-03 10:00:13 +0200166 select HAVE_FTRACE_MCOUNT_RECORD
Ingo Molnar6471b822015-06-03 10:00:13 +0200167 select HAVE_FUNCTION_GRAPH_TRACER
168 select HAVE_FUNCTION_TRACER
Emese Revfy6b90bd42016-05-24 00:09:38 +0200169 select HAVE_GCC_PLUGINS
K.Prasad0067f122009-06-01 23:43:57 +0530170 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200171 select HAVE_IDE
172 select HAVE_IOREMAP_PROT
173 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
174 select HAVE_IRQ_TIME_ACCOUNTING
175 select HAVE_KERNEL_BZIP2
176 select HAVE_KERNEL_GZIP
177 select HAVE_KERNEL_LZ4
178 select HAVE_KERNEL_LZMA
179 select HAVE_KERNEL_LZO
180 select HAVE_KERNEL_XZ
181 select HAVE_KPROBES
182 select HAVE_KPROBES_ON_FTRACE
Masami Hiramatsu540adea2018-01-13 02:55:03 +0900183 select HAVE_FUNCTION_ERROR_INJECTION
Ingo Molnar6471b822015-06-03 10:00:13 +0200184 select HAVE_KRETPROBES
185 select HAVE_KVM
186 select HAVE_LIVEPATCH if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200187 select HAVE_MEMBLOCK_NODE_MAP
Frederic Weisbecker01027522010-04-11 18:55:56 +0200188 select HAVE_MIXED_BREAKPOINTS_REGS
Josh Poimboeufee9f8fc2017-07-24 18:36:57 -0500189 select HAVE_MOD_ARCH_SPECIFIC
Joel Fernandes (Google)9f132f72019-01-03 15:28:41 -0800190 select HAVE_MOVE_PMD
Petr Mladek42a0bb32016-05-20 17:00:33 -0700191 select HAVE_NMI
Ingo Molnar6471b822015-06-03 10:00:13 +0200192 select HAVE_OPROFILE
193 select HAVE_OPTPROBES
194 select HAVE_PCSPKR_PLATFORM
195 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200196 select HAVE_PERF_EVENTS_NMI
Nicholas Piggin92e5aae2017-08-18 15:15:51 -0700197 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
Christoph Hellwigeb01d422018-11-15 20:05:32 +0100198 select HAVE_PCI
Jiri Olsac5e63192012-08-07 15:20:36 +0200199 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200200 select HAVE_PERF_USER_STACK_DUMP
Peter Zijlstra48a8b972018-08-22 17:30:16 +0200201 select HAVE_RCU_TABLE_FREE if PARAVIRT
Ingo Molnar6471b822015-06-03 10:00:13 +0200202 select HAVE_REGS_AND_STACK_ACCESS_API
Jiri Slaby6415b382018-05-18 08:47:13 +0200203 select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION
Masami Hiramatsu3c88ee194c2018-04-25 21:20:57 +0900204 select HAVE_FUNCTION_ARG_ACCESS_API
Masahiro Yamadad148eac2018-06-14 19:36:45 +0900205 select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
Ingo Molnarc763ea22016-11-15 10:26:39 +0100206 select HAVE_STACK_VALIDATION if X86_64
Mathieu Desnoyersd6761b82018-06-02 08:43:58 -0400207 select HAVE_RSEQ
Ingo Molnar6471b822015-06-03 10:00:13 +0200208 select HAVE_SYSCALL_TRACEPOINTS
Ingo Molnar6471b822015-06-03 10:00:13 +0200209 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300210 select HAVE_USER_RETURN_NOTIFIER
Vincenzo Frascino7ac87072019-06-21 10:52:49 +0100211 select HAVE_GENERIC_VDSO
Thomas Gleixner05736e42018-05-29 17:48:27 +0200212 select HOTPLUG_SMT if SMP
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100213 select IRQ_FORCED_THREADING
Christoph Hellwig86596f02018-04-05 09:44:52 +0200214 select NEED_SG_DMA_LENGTH
Christoph Hellwig2eac9c22018-11-15 20:05:33 +0100215 select PCI_DOMAINS if PCI
Sinan Kaya625210c2019-01-21 23:19:58 +0000216 select PCI_LOCKLESS_CONFIG if PCI
Ingo Molnar6471b822015-06-03 10:00:13 +0200217 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500218 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200219 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200220 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500221 select SRCU
Ingo Molnar6471b822015-06-03 10:00:13 +0200222 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700223 select THREAD_INFO_IN_TASK
Ingo Molnar6471b822015-06-03 10:00:13 +0200224 select USER_STACKTRACE_SUPPORT
225 select VIRT_TO_BUS
Ingo Molnar6471b822015-06-03 10:00:13 +0200226 select X86_FEATURE_NAMES if PROC_FS
Aubrey Li0c608da2019-06-06 09:22:35 +0800227 select PROC_PID_ARCH_STATUS if PROC_FS
Balbir Singh7d8330a2008-02-10 12:46:28 +0530228
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200229config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100230 def_bool y
231 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200232
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700233config OUTPUT_FORMAT
234 string
235 default "elf32-i386" if X86_32
236 default "elf64-x86-64" if X86_64
237
Sam Ravnborg73531902008-05-25 23:03:18 +0200238config ARCH_DEFCONFIG
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200239 string
Sam Ravnborg73531902008-05-25 23:03:18 +0200240 default "arch/x86/configs/i386_defconfig" if X86_32
241 default "arch/x86/configs/x86_64_defconfig" if X86_64
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200242
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100243config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100244 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100245
246config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100247 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100248
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100249config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100250 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100251
Daniel Cashman9e08f572016-01-14 15:20:06 -0800252config ARCH_MMAP_RND_BITS_MIN
253 default 28 if 64BIT
254 default 8
255
256config ARCH_MMAP_RND_BITS_MAX
257 default 32 if 64BIT
258 default 16
259
260config ARCH_MMAP_RND_COMPAT_BITS_MIN
261 default 8
262
263config ARCH_MMAP_RND_COMPAT_BITS_MAX
264 default 16
265
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100266config SBUS
267 bool
268
269config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100270 def_bool y
271 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100272
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100273config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100274 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100275 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000276 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
277
278config GENERIC_BUG_RELATIVE_POINTERS
279 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100280
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100281config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100282 def_bool y
283 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100284
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100285config GENERIC_CALIBRATE_DELAY
286 def_bool y
287
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800288config ARCH_HAS_CPU_RELAX
289 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100290
Pekka Enberg1b27d052008-04-28 02:12:22 -0700291config ARCH_HAS_CACHE_LINE_SIZE
292 def_bool y
293
Dave Hansen316d0972018-04-20 15:20:28 -0700294config ARCH_HAS_FILTER_PGPROT
295 def_bool y
296
Mike Travisdd5af902008-01-30 13:33:32 +0100297config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900298 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100299
Tejun Heo08fc4582009-08-14 15:00:49 +0900300config NEED_PER_CPU_EMBED_FIRST_CHUNK
301 def_bool y
302
303config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900304 def_bool y
305
Johannes Berg801e4062007-12-08 02:12:39 +0100306config ARCH_HIBERNATION_POSSIBLE
307 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100308
Johannes Bergf4cb5702007-12-08 02:14:00 +0100309config ARCH_SUSPEND_POSSIBLE
310 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100311
Steve Capper53313b22013-04-30 08:03:42 +0100312config ARCH_WANT_GENERAL_HUGETLB
313 def_bool y
314
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100315config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000316 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100317
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100318config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000319 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100320
Akinobu Mita6a11f752009-03-31 15:23:17 -0700321config ARCH_SUPPORTS_DEBUG_PAGEALLOC
322 def_bool y
323
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300324config KASAN_SHADOW_OFFSET
325 hex
326 depends on KASAN
327 default 0xdffffc0000000000
328
Shane Wang69575d32009-09-01 18:25:07 -0700329config HAVE_INTEL_TXT
330 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700331 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700332
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100333config X86_32_SMP
334 def_bool y
335 depends on X86_32 && SMP
336
337config X86_64_SMP
338 def_bool y
339 depends on X86_64 && SMP
340
Tejun Heoccbeed32009-02-09 22:17:40 +0900341config X86_32_LAZY_GS
342 def_bool y
Masahiro Yamada8458f8c2018-06-14 19:36:43 +0900343 depends on X86_32 && !STACKPROTECTOR
Tejun Heoccbeed32009-02-09 22:17:40 +0900344
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530345config ARCH_SUPPORTS_UPROBES
346 def_bool y
347
Rob Herringd20642f2014-04-18 17:19:54 -0500348config FIX_EARLYCON_MEM
349 def_bool y
350
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +0300351config DYNAMIC_PHYSICAL_MASK
352 bool
353
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700354config PGTABLE_LEVELS
355 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300356 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700357 default 4 if X86_64
358 default 3 if X86_PAE
359 default 2
360
Masahiro Yamada2a61f472018-05-28 18:22:00 +0900361config CC_HAS_SANE_STACKPROTECTOR
362 bool
363 default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
364 default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
365 help
366 We have to make sure stack protector is unconditionally disabled if
367 the compiler produces broken code.
368
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100369menu "Processor type and features"
370
Randy Dunlap5ee71532012-01-16 11:57:18 -0800371config ZONE_DMA
372 bool "DMA memory allocation support" if EXPERT
373 default y
374 help
375 DMA memory allocation support allows devices with less than 32-bit
376 addressing to allocate within the first 16MB of address space.
377 Disable if no such devices will be used.
378
379 If unsure, say Y.
380
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100381config SMP
382 bool "Symmetric multi-processing support"
383 ---help---
384 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800385 a system with only one CPU, say N. If you have a system with more
386 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100387
Robert Graffham4a474152014-01-23 15:55:29 -0800388 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100389 machines, but will use only one CPU of a multiprocessor machine. If
390 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800391 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100392 will run faster if you say N here.
393
394 Note that if you say Y here and choose architecture "586" or
395 "Pentium" under "Processor family", the kernel will not work on 486
396 architectures. Similarly, multiprocessor kernels for the "PPro"
397 architecture may not work on all Pentium based boards.
398
399 People using multiprocessor machines who say Y here should also say
400 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
401 Management" code will be disabled if you say Y here.
402
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -0300403 See also <file:Documentation/x86/i386/IO-APIC.rst>,
Mauro Carvalho Chehab4f4cfa62019-06-27 14:56:51 -0300404 <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100405 <http://www.tldp.org/docs.html#howto>.
406
407 If you don't know what to do here, say N.
408
Josh Triplett9def39be2013-10-30 08:09:45 -0700409config X86_FEATURE_NAMES
410 bool "Processor feature human-readable names" if EMBEDDED
411 default y
412 ---help---
413 This option compiles in a table of x86 feature bits and corresponding
414 names. This is required to support /proc/cpuinfo and a few kernel
415 messages. You can disable this to save space, at the expense of
416 making those few kernel messages show numeric feature bits instead.
417
418 If in doubt, say Y.
419
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800420config X86_X2APIC
421 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200422 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800423 ---help---
424 This enables x2apic support on CPUs that have this feature.
425
426 This allows 32-bit apic IDs (so it can support very large systems),
427 and accesses the local apic via MSRs not via mmio.
428
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800429 If you don't know what to do here, say N.
430
Yinghai Lu6695c852008-06-19 12:13:09 -0700431config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700432 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000433 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200434 depends on X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100435 ---help---
Yinghai Lu6695c852008-06-19 12:13:09 -0700436 For old smp systems that do not have proper acpi support. Newer systems
437 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700438
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000439config GOLDFISH
440 def_bool y
441 depends on X86_GOLDFISH
442
David Woodhouse76b04382018-01-11 21:46:25 +0000443config RETPOLINE
444 bool "Avoid speculative indirect branches in kernel"
445 default y
Peter Zijlstrad5028ba2018-02-06 09:46:13 +0100446 select STACK_VALIDATION if HAVE_STACK_VALIDATION
David Woodhouse76b04382018-01-11 21:46:25 +0000447 help
448 Compile kernel with the retpoline compiler options to guard against
449 kernel-to-user data leaks by avoiding speculative indirect
450 branches. Requires a compiler with -mindirect-branch=thunk-extern
451 support for full protection. The kernel may run slower.
452
Johannes Weinere6d42932019-01-29 17:44:36 -0500453config X86_CPU_RESCTRL
454 bool "x86 CPU resource control support"
Babu Moger6fe07ce2018-11-21 20:28:39 +0000455 depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100456 select KERNFS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700457 help
Johannes Weinere6d42932019-01-29 17:44:36 -0500458 Enable x86 CPU resource control support.
Babu Moger6fe07ce2018-11-21 20:28:39 +0000459
460 Provide support for the allocation and monitoring of system resources
461 usage by the CPU.
462
463 Intel calls this Intel Resource Director Technology
464 (Intel(R) RDT). More information about RDT can be found in the
465 Intel x86 Architecture Software Developer Manual.
466
467 AMD calls this AMD Platform Quality of Service (AMD QoS).
468 More information about AMD QoS can be found in the AMD64 Technology
469 Platform Quality of Service Extensions manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700470
471 Say N if unsure.
472
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800473if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800474config X86_BIGSMP
475 bool "Support for big SMP systems with more than 8 CPUs"
476 depends on SMP
477 ---help---
478 This option is needed for the systems that have more than 8 CPUs
479
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800480config X86_EXTENDED_PLATFORM
481 bool "Support for extended (non-PC) x86 platforms"
482 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100483 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100484 If you disable this option then the kernel will only support
485 standard PC platforms. (which covers the vast majority of
486 systems out there.)
487
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800488 If you enable this option then you'll be able to select support
489 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100490 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800491 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800492 RDC R-321x SoC
493 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200494 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200495 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100496
497 If you have one of these systems, or if you want to build a
498 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800499endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100500
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800501if X86_64
502config X86_EXTENDED_PLATFORM
503 bool "Support for extended (non-PC) x86 platforms"
504 default y
505 ---help---
506 If you disable this option then the kernel will only support
507 standard PC platforms. (which covers the vast majority of
508 systems out there.)
509
510 If you enable this option then you'll be able to select support
511 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800512 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800513 ScaleMP vSMP
514 SGI Ultraviolet
515
516 If you have one of these systems, or if you want to build a
517 generic distribution kernel, say Y here - otherwise say N.
518endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800519# This is an alphabetically sorted list of 64 bit extended platforms
520# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800521config X86_NUMACHIP
522 bool "Numascale NumaChip"
523 depends on X86_64
524 depends on X86_EXTENDED_PLATFORM
525 depends on NUMA
526 depends on SMP
527 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700528 depends on PCI_MMCONFIG
Steffen Persvold44b111b52011-12-06 00:07:26 +0800529 ---help---
530 Adds support for Numascale NumaChip large-SMP systems. Needed to
531 enable more than ~168 cores.
532 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100533
Ingo Molnar6a485652009-01-27 18:29:13 +0100534config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800535 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100536 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100537 select PARAVIRT
538 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800539 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300540 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100541 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100542 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
543 supposed to run on these EM64T-based machines. Only choose this option
544 if you have one of these machines.
545
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800546config X86_UV
547 bool "SGI Ultraviolet"
548 depends on X86_64
549 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500550 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800551 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700552 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200553 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800554 ---help---
555 This option is needed in order to support SGI Ultraviolet systems.
556 If you don't have one of these, you should say N here.
557
558# Following is an alphabetically sorted list of 32 bit extended platforms
559# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100560
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000561config X86_GOLDFISH
562 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100563 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000564 ---help---
565 Enable support for the Goldfish virtual platform used primarily
566 for Android development. Unless you are building for the Android
567 Goldfish emulator say N here.
568
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800569config X86_INTEL_CE
570 bool "CE4100 TV platform"
571 depends on PCI
572 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800573 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800574 depends on X86_32
575 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800576 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100577 select OF
578 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800579 ---help---
580 Select for the Intel CE media processor (CE4100) SOC.
581 This option compiles in support for the CE4100 SOC for settop
582 boxes and media devices.
583
David Cohen4cb9b002013-12-16 17:37:26 -0800584config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100585 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100586 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800587 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000588 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200589 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000590 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000591 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800592 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000593 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000594 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000595 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000596 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000597 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800598 Select to build a kernel capable of supporting Intel MID (Mobile
599 Internet Device) platform systems which do not have the PCI legacy
600 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000601
David Cohen4cb9b002013-12-16 17:37:26 -0800602 Intel MID platforms are based on an Intel processor and chipset which
603 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100604
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000605config X86_INTEL_QUARK
606 bool "Intel Quark platform support"
607 depends on X86_32
608 depends on X86_EXTENDED_PLATFORM
609 depends on X86_PLATFORM_DEVICES
610 depends on X86_TSC
611 depends on PCI
612 depends on PCI_GOANY
613 depends on X86_IO_APIC
614 select IOSF_MBI
615 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200616 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000617 ---help---
618 Select to include support for Quark X1000 SoC.
619 Say Y here if you have a Quark based system such as the Arduino
620 compatible Intel Galileo.
621
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000622config X86_INTEL_LPSS
623 bool "Intel Low Power Subsystem Support"
Sinan Kaya5962dd22019-01-02 18:10:37 +0000624 depends on X86 && ACPI && PCI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000625 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300626 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100627 select IOSF_MBI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000628 ---help---
629 Select to build support for Intel Low Power Subsystem such as
630 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300631 things like clock tree (common clock framework) and pincontrol
632 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000633
Ken Xue92082a82015-02-06 08:27:51 +0800634config X86_AMD_PLATFORM_DEVICE
635 bool "AMD ACPI2Platform devices support"
636 depends on ACPI
637 select COMMON_CLK
638 select PINCTRL
639 ---help---
640 Select to interpret AMD specific ACPI device to platform device
641 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
642 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
643 implemented under PINCTRL subsystem.
644
David E. Boxced3ce72014-09-17 22:13:50 -0700645config IOSF_MBI
646 tristate "Intel SoC IOSF Sideband support for SoC platforms"
647 depends on PCI
648 ---help---
649 This option enables sideband register access support for Intel SoC
650 platforms. On these platforms the IOSF sideband is used in lieu of
651 MSR's for some register accesses, mostly but not limited to thermal
652 and power. Drivers may query the availability of this device to
653 determine if they need the sideband in order to work on these
654 platforms. The sideband is available on the following SoC products.
655 This list is not meant to be exclusive.
656 - BayTrail
657 - Braswell
658 - Quark
659
660 You should say Y if you are running a kernel on one of these SoC's.
661
David E. Boxed2226b2014-09-17 22:13:51 -0700662config IOSF_MBI_DEBUG
663 bool "Enable IOSF sideband access through debugfs"
664 depends on IOSF_MBI && DEBUG_FS
665 ---help---
666 Select this option to expose the IOSF sideband access registers (MCR,
667 MDR, MCRX) through debugfs to write and read register information from
668 different units on the SoC. This is most useful for obtaining device
669 state information for debug and analysis. As this is a general access
670 mechanism, users of this option would have specific knowledge of the
671 device they want to access.
672
673 If you don't require the option or are in doubt, say N.
674
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800675config X86_RDC321X
676 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100677 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800678 depends on X86_EXTENDED_PLATFORM
679 select M486
680 select X86_REBOOTFIXUPS
681 ---help---
682 This option is needed for RDC R-321x system-on-chip, also known
683 as R-8610-(G).
684 If you don't have one of these chips, you should say N here.
685
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100686config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100687 bool "Support non-standard 32-bit SMP architectures"
688 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800689 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100690 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800691 This option compiles in the bigsmp and STA2X11 default
692 subarchitectures. It is intended for a generic binary
693 kernel. If you select them all, kernel will probe it one by
694 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700695
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800696# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700697
Linus Torvaldsd949f362009-09-26 09:35:07 -0700698config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100699 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700700 # MCE code calls memory_failure():
701 depends on X86_MCE
702 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700703 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
704 depends on X86_64 || !SPARSEMEM
705 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700706
Alessandro Rubini83125a32012-04-04 19:40:21 +0200707config STA2X11
708 bool "STA2X11 Companion Chip Support"
709 depends on X86_32_NON_STANDARD && PCI
Christoph Hellwigb6e05472018-03-19 11:38:24 +0100710 select ARCH_HAS_PHYS_TO_DMA
Alessandro Rubini83125a32012-04-04 19:40:21 +0200711 select SWIOTLB
712 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200713 select GPIOLIB
Alessandro Rubini83125a32012-04-04 19:40:21 +0200714 ---help---
715 This adds support for boards based on the STA2X11 IO-Hub,
716 a.k.a. "ConneXt". The chip is used in place of the standard
717 PC chipset, so all "standard" peripherals are missing. If this
718 option is selected the kernel will still be able to boot on
719 standard PC machines.
720
Shérab82148d12010-09-25 06:06:57 +0200721config X86_32_IRIS
722 tristate "Eurobraille/Iris poweroff module"
723 depends on X86_32
724 ---help---
725 The Iris machines from EuroBraille do not have APM or ACPI support
726 to shut themselves down properly. A special I/O sequence is
727 needed to do so, which is what this module does at
728 kernel shutdown.
729
730 This is only for Iris machines from EuroBraille.
731
732 If unused, say N.
733
Ingo Molnarae1e9132008-11-11 09:05:16 +0100734config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100735 def_bool y
736 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800737 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100738 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100739 Calculate simpler /proc/<PID>/wchan values. If this option
740 is disabled then wchan values will recurse back to the
741 caller function. This provides more accurate wchan values,
742 at the expense of slightly more scheduling overhead.
743
744 If in doubt, say "Y".
745
Borislav Petkov6276a072013-03-04 21:20:21 +0100746menuconfig HYPERVISOR_GUEST
747 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100748 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100749 Say Y here to enable options for running Linux under various hyper-
750 visors. This option enables basic hypervisor detection and platform
751 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100752
Borislav Petkov6276a072013-03-04 21:20:21 +0100753 If you say N, all options in this submenu will be skipped and
754 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100755
Borislav Petkov6276a072013-03-04 21:20:21 +0100756if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100757
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100758config PARAVIRT
759 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100760 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100761 This changes the kernel so it can modify itself when it is run
762 under a hypervisor, potentially improving performance significantly
763 over full virtualization. However, when run without a hypervisor
764 the kernel is theoretically slower and slightly larger.
765
Juergen Grossc00a2802018-08-28 09:40:21 +0200766config PARAVIRT_XXL
767 bool
768
Borislav Petkov6276a072013-03-04 21:20:21 +0100769config PARAVIRT_DEBUG
770 bool "paravirt-ops debugging"
771 depends on PARAVIRT && DEBUG_KERNEL
772 ---help---
773 Enable to debug paravirt_ops internals. Specifically, BUG if
774 a paravirt_op is missing when it is called.
775
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700776config PARAVIRT_SPINLOCKS
777 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700778 depends on PARAVIRT && SMP
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700779 ---help---
780 Paravirtualized spinlocks allow a pvops backend to replace the
781 spinlock implementation with something virtualization-friendly
782 (for example, block the virtual CPU rather than spinning).
783
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530784 It has a minimal impact on native kernels and gives a nice performance
785 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700786
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530787 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700788
Zhao Yakuiecca25022019-04-30 11:45:23 +0800789config X86_HV_CALLBACK_VECTOR
790 def_bool n
791
Borislav Petkov6276a072013-03-04 21:20:21 +0100792source "arch/x86/xen/Kconfig"
793
794config KVM_GUEST
795 bool "KVM Guest support (including kvmclock)"
796 depends on PARAVIRT
797 select PARAVIRT_CLOCK
798 default y
799 ---help---
800 This option enables various optimizations for running under the KVM
801 hypervisor. It includes a paravirtualized clock, so that instead
802 of relying on a PIT (or probably other) emulation by the
803 underlying device model, the host provides the guest with
804 timing infrastructure such as time of day, and system time
805
Maran Wilson77336072018-12-10 11:07:28 -0800806config PVH
807 bool "Support for running PVH guests"
808 ---help---
809 This option enables the PVH entry point for guest virtual machines
810 as specified in the x86/HVM direct boot ABI.
811
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530812config KVM_DEBUG_FS
813 bool "Enable debug information for KVM Guests in debugfs"
814 depends on KVM_GUEST && DEBUG_FS
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530815 ---help---
816 This option enables collection of various statistics for KVM guest.
817 Statistics are displayed in debugfs filesystem. Enabling this option
818 may incur significant overhead.
819
Borislav Petkov6276a072013-03-04 21:20:21 +0100820config PARAVIRT_TIME_ACCOUNTING
821 bool "Paravirtual steal time accounting"
822 depends on PARAVIRT
Borislav Petkov6276a072013-03-04 21:20:21 +0100823 ---help---
824 Select this option to enable fine granularity task steal time
825 accounting. Time spent executing other tasks in parallel with
826 the current vCPU is discounted from the vCPU power. To account for
827 that, there can be a small performance impact.
828
829 If in doubt, say N here.
830
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200831config PARAVIRT_CLOCK
832 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200833
Jan Kiszka4a362602017-11-27 09:11:46 +0100834config JAILHOUSE_GUEST
835 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100836 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100837 select X86_PM_TIMER
Jan Kiszka4a362602017-11-27 09:11:46 +0100838 ---help---
839 This option allows to run Linux as guest in a Jailhouse non-root
840 cell. You can leave this option disabled if you only want to start
841 Jailhouse and run Linux afterwards in the root cell.
842
Zhao Yakuiec7972c2019-04-30 11:45:24 +0800843config ACRN_GUEST
844 bool "ACRN Guest support"
845 depends on X86_64
Zhao Yakui498ad392019-04-30 11:45:25 +0800846 select X86_HV_CALLBACK_VECTOR
Zhao Yakuiec7972c2019-04-30 11:45:24 +0800847 help
848 This option allows to run Linux as guest in the ACRN hypervisor. ACRN is
849 a flexible, lightweight reference open-source hypervisor, built with
850 real-time and safety-criticality in mind. It is built for embedded
851 IOT with small footprint and real-time features. More details can be
852 found in https://projectacrn.org/.
853
Borislav Petkov6276a072013-03-04 21:20:21 +0100854endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400855
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100856source "arch/x86/Kconfig.cpu"
857
858config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100859 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100860 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100861 ---help---
862 Use the IA-PC HPET (High Precision Event Timer) to manage
863 time in preference to the PIT and RTC, if a HPET is
864 present.
865 HPET is the next generation timer replacing legacy 8254s.
866 The HPET provides a stable time base on SMP
867 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200868 as it is off-chip. The interface used is documented
869 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100870
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100871 You can safely choose Y here. However, HPET will only be
872 activated if the platform and the BIOS support this feature.
873 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100874
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100875 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100876
877config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100878 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800879 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100880
Jacob Panbb24c472009-09-02 07:37:17 -0700881config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000882 def_bool y if X86_INTEL_MID
883 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100884 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000885 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700886 help
887 APB timer is the replacement for 8254, HPET on X86 MID platforms.
888 The APBT provides a stable time base on SMP
889 systems, unlike the TSC, but it is more expensive to access,
890 as it is off-chip. APB timers are always running regardless of CPU
891 C states, they are used as per CPU clockevent device when possible.
892
David Rientjes6a108a12011-01-20 14:44:16 -0800893# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100894# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700895config DMI
896 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800897 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800898 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100899 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700900 Enabled scanning of DMI to identify machine quirks. Say Y
901 here unless you have verified that your setup is not
902 affected by entries in the DMI blacklist. Required by PNP
903 BIOS code.
904
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100905config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700906 bool "Old AMD GART IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200907 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100908 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200909 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100910 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200911 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
912 GART based hardware IOMMUs.
913
914 The GART supports full DMA access for devices with 32-bit access
915 limitations, on systems with more than 3 GB. This is usually needed
916 for USB, sound, many IDE/SATA chipsets and some other devices.
917
918 Newer systems typically have a modern AMD IOMMU, supported via
919 the CONFIG_AMD_IOMMU=y config option.
920
921 In normal configurations this driver is only active when needed:
922 there's more than 3 GB of memory and the system contains a
923 32-bit limited device.
924
925 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100926
927config CALGARY_IOMMU
928 bool "IBM Calgary IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200929 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100930 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700931 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100932 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100933 Support for hardware IOMMUs in IBM's xSeries x366 and x460
934 systems. Needed to run systems with more than 3GB of memory
935 properly with 32-bit PCI devices that do not support DAC
936 (Double Address Cycle). Calgary also supports bus level
937 isolation, where all DMAs pass through the IOMMU. This
938 prevents them from going anywhere except their intended
939 destination. This catches hard-to-find kernel bugs and
940 mis-behaving drivers and devices that do not use the DMA-API
941 properly to set up their DMA buffers. The IOMMU can be
942 turned off at boot time with the iommu=off parameter.
943 Normally the kernel will make the right choice by itself.
944 If unsure, say Y.
945
946config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100947 def_bool y
948 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100949 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100950 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100951 Should Calgary be enabled by default? if you choose 'y', Calgary
952 will be used (if it exists). If you choose 'n', Calgary will not be
953 used even if it exists. If you choose 'n' and would like to use
954 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
955 If unsure, say Y.
956
Mike Travis1184dc22008-05-12 21:21:12 +0200957config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200958 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700959 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800960 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100961 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200962 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200963 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100964
Ingo Molnaraec64872018-02-10 12:36:29 +0100965#
966# The maximum number of CPUs supported:
967#
968# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
969# and which can be configured interactively in the
970# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
971#
972# The ranges are different on 32-bit and 64-bit kernels, depending on
973# hardware capabilities and scalability features of the kernel.
974#
975# ( If MAXSMP is enabled we just use the highest possible value and disable
976# interactive configuration. )
977#
978
979config NR_CPUS_RANGE_BEGIN
980 int
981 default NR_CPUS_RANGE_END if MAXSMP
982 default 1 if !SMP
983 default 2
984
985config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800986 int
987 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100988 default 64 if SMP && X86_BIGSMP
989 default 8 if SMP && !X86_BIGSMP
990 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800991
Ingo Molnaraec64872018-02-10 12:36:29 +0100992config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800993 int
994 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100995 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
996 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
997 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800998
Ingo Molnaraec64872018-02-10 12:36:29 +0100999config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -08001000 int
1001 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +01001002 default 32 if X86_BIGSMP
1003 default 8 if SMP
1004 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -08001005
Ingo Molnaraec64872018-02-10 12:36:29 +01001006config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -08001007 int
1008 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +01001009 default 8192 if MAXSMP
1010 default 64 if SMP
1011 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -08001012
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001013config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -08001014 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +01001015 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
1016 default NR_CPUS_DEFAULT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001017 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001018 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -05001019 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +03001020 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001021 minimum value which makes sense is 2.
1022
Ingo Molnaraec64872018-02-10 12:36:29 +01001023 This is purely to save memory: each supported CPU adds about 8KB
1024 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001025
1026config SCHED_SMT
Thomas Gleixnerdbe73362018-11-25 19:33:37 +01001027 def_bool y if SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001028
1029config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001030 def_bool y
1031 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001032 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001033 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001034 Multi-core scheduler support improves the CPU scheduler's decision
1035 making when dealing with multi-core CPU chips at a cost of slightly
1036 increased overhead in some places. If unsure say N here.
1037
Tim Chende966cf2016-11-29 10:43:27 -08001038config SCHED_MC_PRIO
1039 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001040 depends on SCHED_MC && CPU_SUP_INTEL
1041 select X86_INTEL_PSTATE
1042 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001043 default y
Tim Chen5e76b2a2016-11-22 12:23:55 -08001044 ---help---
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001045 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1046 core ordering determined at manufacturing time, which allows
1047 certain cores to reach higher turbo frequencies (when running
1048 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001049
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001050 Enabling this kernel feature teaches the scheduler about
1051 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1052 scheduler's CPU selection logic accordingly, so that higher
1053 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001054
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001055 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001056
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001057 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001058
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001059config UP_LATE_INIT
1060 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +01001061 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001062
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001063config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001064 bool "Local APIC support on uniprocessors" if !PCI_MSI
1065 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001066 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001067 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001068 A local APIC (Advanced Programmable Interrupt Controller) is an
1069 integrated interrupt controller in the CPU. If you have a single-CPU
1070 system which has a processor with a local APIC, you can say Y here to
1071 enable and use it. If you say Y here even though your machine doesn't
1072 have a local APIC, then the kernel will still run with no slowdown at
1073 all. The local APIC supports CPU-generated self-interrupts (timer,
1074 performance counters), and the NMI watchdog which detects hard
1075 lockups.
1076
1077config X86_UP_IOAPIC
1078 bool "IO-APIC support on uniprocessors"
1079 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001080 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001081 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1082 SMP-capable replacement for PC-style interrupt controllers. Most
1083 SMP systems and many recent uniprocessor systems have one.
1084
1085 If you have a single-CPU system with an IO-APIC, you can say Y here
1086 to use it. If you say Y here even though your machine doesn't have
1087 an IO-APIC, then the kernel will still run with no slowdown at all.
1088
1089config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001090 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001091 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001092 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001093 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001094
1095config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001096 def_bool y
1097 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001098
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001099config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1100 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001101 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001102 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001103 This option enables a workaround that fixes a source of
1104 spurious interrupts. This is recommended when threaded
1105 interrupt handling is used on systems where the generation of
1106 superfluous "boot interrupts" cannot be disabled.
1107
1108 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1109 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1110 kernel does during interrupt handling). On chipsets where this
1111 boot IRQ generation cannot be disabled, this workaround keeps
1112 the original IRQ line masked so that only the equivalent "boot
1113 IRQ" is delivered to the CPUs. The workaround also tells the
1114 kernel to set up the IRQ handler on the boot IRQ line. In this
1115 way only one interrupt is delivered to the kernel. Otherwise
1116 the spurious second interrupt may cause the kernel to bring
1117 down (vital) interrupt lines.
1118
1119 Only affects "broken" chipsets. Interrupt sharing may be
1120 increased on these systems.
1121
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001122config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001123 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001124 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001125 default y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001126 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +02001127 Machine Check support allows the processor to notify the
1128 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001129 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001130 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001131
Tony Luck5de97c92017-03-27 11:33:03 +02001132config X86_MCELOG_LEGACY
1133 bool "Support for deprecated /dev/mcelog character device"
1134 depends on X86_MCE
1135 ---help---
1136 Enable support for /dev/mcelog which is needed by the old mcelog
1137 userspace logging daemon. Consider switching to the new generation
1138 rasdaemon solution.
1139
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001140config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001141 def_bool y
1142 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001143 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001144 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001145 Additional support for intel specific MCE features such as
1146 the thermal monitor.
1147
1148config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001149 def_bool y
1150 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001151 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001152 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001153 Additional support for AMD specific MCE features such as
1154 the DRAM Error Threshold.
1155
Andi Kleen4efc0672009-04-28 19:07:31 +02001156config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001157 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001158 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001159 ---help---
1160 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001161 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001162 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001163
Andi Kleenb2762682009-02-12 13:49:31 +01001164config X86_MCE_THRESHOLD
1165 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001166 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001167
Andi Kleenea149b32009-04-29 19:31:00 +02001168config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001169 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001170 tristate "Machine check injector support"
1171 ---help---
1172 Provide support for injecting machine checks for testing purposes.
1173 If you don't know what a machine check is and you don't do kernel
1174 QA it is safe to say n.
1175
Andi Kleen4efc0672009-04-28 19:07:31 +02001176config X86_THERMAL_VECTOR
1177 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001178 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001179
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001180source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001181
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001182config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001183 bool "Legacy VM86 support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001184 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001185 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001186 This option allows user programs to put the CPU into V8086
1187 mode, which is an 80286-era approximation of 16-bit real mode.
1188
1189 Some very old versions of X and/or vbetool require this option
1190 for user mode setting. Similarly, DOSEMU will use it if
1191 available to accelerate real mode DOS programs. However, any
1192 recent version of DOSEMU, X, or vbetool should be fully
1193 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001194 fall back to software emulation. Nevertheless, if you are using
1195 a 16-bit DOS program where 16-bit performance matters, vm86
1196 mode might be faster than emulation and you might want to
1197 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001198
Ingo Molnar1e642812015-09-05 08:58:10 +02001199 Note that any app that works on a 64-bit kernel is unlikely to
1200 need this option, as 64-bit kernels don't, and can't, support
1201 V8086 mode. This option is also unrelated to 16-bit protected
1202 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001203
Ingo Molnar1e642812015-09-05 08:58:10 +02001204 Enabling this option increases the complexity of the kernel
1205 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001206
Ingo Molnar1e642812015-09-05 08:58:10 +02001207 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001208
1209config VM86
1210 bool
1211 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001212
1213config X86_16BIT
1214 bool "Enable support for 16-bit segments" if EXPERT
1215 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001216 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001217 ---help---
1218 This option is required by programs like Wine to run 16-bit
1219 protected mode legacy code on x86 processors. Disabling
1220 this option saves about 300 bytes on i386, or around 6K text
1221 plus 16K runtime memory on x86-64,
1222
1223config X86_ESPFIX32
1224 def_bool y
1225 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001226
H. Peter Anvin197725d2014-05-04 10:00:49 -07001227config X86_ESPFIX64
1228 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001229 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001230
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001231config X86_VSYSCALL_EMULATION
1232 bool "Enable vsyscall emulation" if EXPERT
1233 default y
1234 depends on X86_64
1235 ---help---
1236 This enables emulation of the legacy vsyscall page. Disabling
1237 it is roughly equivalent to booting with vsyscall=none, except
1238 that it will also disable the helpful warning if a program
1239 tries to use a vsyscall. With this option set to N, offending
1240 programs will just segfault, citing addresses of the form
1241 0xffffffffff600?00.
1242
1243 This option is required by many programs built before 2013, and
1244 care should be used even with newer programs if set to N.
1245
1246 Disabling this option saves about 7K of kernel size and
1247 possibly 4K of additional runtime pagetable memory.
1248
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001249config TOSHIBA
1250 tristate "Toshiba Laptop support"
1251 depends on X86_32
1252 ---help---
1253 This adds a driver to safely access the System Management Mode of
1254 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1255 not work on models with a Phoenix BIOS. The System Management Mode
1256 is used to set the BIOS and power saving options on Toshiba portables.
1257
1258 For information on utilities to make use of this driver see the
1259 Toshiba Linux utilities web site at:
1260 <http://www.buzzard.org.uk/toshiba/>.
1261
1262 Say Y if you intend to run this kernel on a Toshiba portable.
1263 Say N otherwise.
1264
1265config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001266 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001267 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001268 select SENSORS_DELL_SMM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001269 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001270 This option enables legacy /proc/i8k userspace interface in hwmon
1271 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1272 temperature and allows controlling fan speeds of Dell laptops via
1273 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1274 it reports also power and hotkey status. For fan speed control is
1275 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001276
Pali Rohár039ae582015-05-14 13:16:37 +02001277 Say Y if you intend to run this kernel on old Dell laptops or want to
1278 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001279 Say N otherwise.
1280
1281config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001282 bool "Enable X86 board specific fixups for reboot"
1283 depends on X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001284 ---help---
1285 This enables chipset and/or board specific fixups to be done
1286 in order to get reboot to work correctly. This is only needed on
1287 some combinations of hardware and BIOS. The symptom, for which
1288 this config is intended, is when reboot ends with a stalled/hung
1289 system.
1290
1291 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001292 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001293
1294 Say Y if you want to enable the fixup. Currently, it's safe to
1295 enable this option even if you don't need it.
1296 Say N otherwise.
1297
1298config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001299 bool "CPU microcode loading support"
1300 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001301 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001302 select FW_LOADER
1303 ---help---
1304 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001305 Intel and AMD processors. The Intel support is for the IA32 family,
1306 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1307 AMD support is for families 0x10 and later. You will obviously need
1308 the actual microcode binary data itself which is not shipped with
1309 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001310
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001311 The preferred method to load microcode from a detached initrd is described
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001312 in Documentation/x86/microcode.rst. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001313 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1314 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001315
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001316 In addition, you can build the microcode into the kernel. For that you
1317 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1318 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001319
Peter Oruba8d86f392008-07-28 18:44:21 +02001320config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001321 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001322 depends on MICROCODE
1323 default MICROCODE
1324 select FW_LOADER
1325 ---help---
1326 This options enables microcode patch loading support for Intel
1327 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001328
Alanb8989db2014-01-20 18:01:56 +00001329 For the current Intel microcode data package go to
1330 <https://downloadcenter.intel.com> and search for
1331 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001332
Peter Oruba80cc9f12008-07-28 18:44:22 +02001333config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001334 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001335 depends on MICROCODE
1336 select FW_LOADER
1337 ---help---
1338 If you select this option, microcode patch loading support for AMD
1339 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001340
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001341config MICROCODE_OLD_INTERFACE
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001342 bool "Ancient loading interface (DEPRECATED)"
1343 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001344 depends on MICROCODE
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001345 ---help---
1346 DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface
1347 which was used by userspace tools like iucode_tool and microcode.ctl.
1348 It is inadequate because it runs too late to be able to properly
1349 load microcode on a machine and it needs special tools. Instead, you
1350 should've switched to the early loading method with the initrd or
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001351 builtin microcode by now: Documentation/x86/microcode.rst
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001352
1353config X86_MSR
1354 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001355 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001356 This device gives privileged processes access to the x86
1357 Model-Specific Registers (MSRs). It is a character device with
1358 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1359 MSR accesses are directed to a specific CPU on multi-processor
1360 systems.
1361
1362config X86_CPUID
1363 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001364 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001365 This device gives processes access to the x86 CPUID instruction to
1366 be executed on a specific processor. It is a character device
1367 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1368 /dev/cpu/31/cpuid.
1369
1370choice
1371 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001372 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001373 depends on X86_32
1374
1375config NOHIGHMEM
1376 bool "off"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001377 ---help---
1378 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1379 However, the address space of 32-bit x86 processors is only 4
1380 Gigabytes large. That means that, if you have a large amount of
1381 physical memory, not all of it can be "permanently mapped" by the
1382 kernel. The physical memory that's not permanently mapped is called
1383 "high memory".
1384
1385 If you are compiling a kernel which will never run on a machine with
1386 more than 1 Gigabyte total physical RAM, answer "off" here (default
1387 choice and suitable for most users). This will result in a "3GB/1GB"
1388 split: 3GB are mapped so that each process sees a 3GB virtual memory
1389 space and the remaining part of the 4GB virtual memory space is used
1390 by the kernel to permanently map as much physical memory as
1391 possible.
1392
1393 If the machine has between 1 and 4 Gigabytes physical RAM, then
1394 answer "4GB" here.
1395
1396 If more than 4 Gigabytes is used then answer "64GB" here. This
1397 selection turns Intel PAE (Physical Address Extension) mode on.
1398 PAE implements 3-level paging on IA32 processors. PAE is fully
1399 supported by Linux, PAE mode is implemented on all recent Intel
1400 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1401 then the kernel will not boot on CPUs that don't support PAE!
1402
1403 The actual amount of total physical memory will either be
1404 auto detected or can be forced by using a kernel command line option
1405 such as "mem=256M". (Try "man bootparam" or see the documentation of
1406 your boot loader (lilo or loadlin) about how to pass options to the
1407 kernel at boot time.)
1408
1409 If unsure, say "off".
1410
1411config HIGHMEM4G
1412 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001413 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001414 Select this if you have a 32-bit processor and between 1 and 4
1415 gigabytes of physical RAM.
1416
1417config HIGHMEM64G
1418 bool "64GB"
Matthew Whitehead69b8d3f2018-02-15 11:54:55 -05001419 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001420 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001421 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001422 Select this if you have a 32-bit processor and more than 4
1423 gigabytes of physical RAM.
1424
1425endchoice
1426
1427choice
David Rientjes6a108a12011-01-20 14:44:16 -08001428 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001429 default VMSPLIT_3G
1430 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001431 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001432 Select the desired split between kernel and user memory.
1433
1434 If the address range available to the kernel is less than the
1435 physical memory installed, the remaining memory will be available
1436 as "high memory". Accessing high memory is a little more costly
1437 than low memory, as it needs to be mapped into the kernel first.
1438 Note that increasing the kernel address space limits the range
1439 available to user programs, making the address space there
1440 tighter. Selecting anything other than the default 3G/1G split
1441 will also likely make your kernel incompatible with binary-only
1442 kernel modules.
1443
1444 If you are not absolutely sure what you are doing, leave this
1445 option alone!
1446
1447 config VMSPLIT_3G
1448 bool "3G/1G user/kernel split"
1449 config VMSPLIT_3G_OPT
1450 depends on !X86_PAE
1451 bool "3G/1G user/kernel split (for full 1G low memory)"
1452 config VMSPLIT_2G
1453 bool "2G/2G user/kernel split"
1454 config VMSPLIT_2G_OPT
1455 depends on !X86_PAE
1456 bool "2G/2G user/kernel split (for full 2G low memory)"
1457 config VMSPLIT_1G
1458 bool "1G/3G user/kernel split"
1459endchoice
1460
1461config PAGE_OFFSET
1462 hex
1463 default 0xB0000000 if VMSPLIT_3G_OPT
1464 default 0x80000000 if VMSPLIT_2G
1465 default 0x78000000 if VMSPLIT_2G_OPT
1466 default 0x40000000 if VMSPLIT_1G
1467 default 0xC0000000
1468 depends on X86_32
1469
1470config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001471 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001472 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001473
1474config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001475 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001476 depends on X86_32 && !HIGHMEM4G
Christoph Hellwigd4a451d2018-04-03 16:24:20 +02001477 select PHYS_ADDR_T_64BIT
Christian Melki9d99c712015-10-05 17:31:33 +02001478 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001479 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001480 PAE is required for NX support, and furthermore enables
1481 larger swapspace support for non-overcommit purposes. It
1482 has the cost of more pagetable lookup overhead, and also
1483 consumes more pagetable space per process.
1484
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001485config X86_5LEVEL
1486 bool "Enable 5-level page tables support"
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001487 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001488 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001489 depends on X86_64
1490 ---help---
1491 5-level paging enables access to larger address space:
1492 upto 128 PiB of virtual address space and 4 PiB of
1493 physical address space.
1494
1495 It will be supported by future Intel CPUs.
1496
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001497 A kernel with the option enabled can be booted on machines that
1498 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001499
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001500 See Documentation/x86/x86_64/5level-paging.rst for more
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001501 information.
1502
1503 Say N if unsure.
1504
Ingo Molnar10971ab2015-03-05 08:18:23 +01001505config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001506 def_bool y
Levin, Alexander (Sasha Levin)4675ff02017-11-15 17:36:02 -08001507 depends on X86_64 && !DEBUG_PAGEALLOC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001508 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001509 Certain kernel features effectively disable kernel
1510 linear 1 GB mappings (even if the CPU otherwise
1511 supports them), so don't confuse the user by printing
1512 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001513
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001514config X86_CPA_STATISTICS
1515 bool "Enable statistic for Change Page Attribute"
1516 depends on DEBUG_FS
1517 ---help---
1518 Expose statistics about the Change Page Attribute mechanims, which
Colin Ian Kinga9432452019-04-16 11:57:51 +01001519 helps to determine the effectiveness of preserving large and huge
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001520 page mappings when mapping protections are changed.
1521
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001522config AMD_MEM_ENCRYPT
1523 bool "AMD Secure Memory Encryption (SME) support"
1524 depends on X86_64 && CPU_SUP_AMD
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +03001525 select DYNAMIC_PHYSICAL_MASK
Ard Biesheuvelce9084b2019-02-02 10:41:17 +01001526 select ARCH_USE_MEMREMAP_PROT
Tom Lendacky9087c372019-07-10 19:01:19 +00001527 select ARCH_HAS_FORCE_DMA_UNENCRYPTED
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001528 ---help---
1529 Say yes to enable support for the encryption of system memory.
1530 This requires an AMD processor that supports Secure Memory
1531 Encryption (SME).
1532
1533config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1534 bool "Activate AMD Secure Memory Encryption (SME) by default"
1535 default y
1536 depends on AMD_MEM_ENCRYPT
1537 ---help---
1538 Say yes to have system memory encrypted by default if running on
1539 an AMD processor that supports Secure Memory Encryption (SME).
1540
1541 If set to Y, then the encryption of system memory can be
1542 deactivated with the mem_encrypt=off command line option.
1543
1544 If set to N, then the encryption of system memory can be
1545 activated with the mem_encrypt=on command line option.
1546
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001547# Common NUMA Features
1548config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001549 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001550 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001551 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1552 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001553 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001554 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001555
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001556 The kernel will try to allocate memory used by a CPU on the
1557 local memory controller of the CPU and add some more
1558 NUMA awareness to the kernel.
1559
Ingo Molnarc280ea52008-11-08 13:29:45 +01001560 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001561 (or later), AMD Opteron, or EM64T NUMA.
1562
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001563 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001564 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001565
1566 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001567
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001568config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001569 def_bool y
1570 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001571 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001572 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001573 Enable AMD NUMA node topology detection. You should say Y here if
1574 you have a multi processor AMD system. This uses an old method to
1575 read the NUMA configuration directly from the builtin Northbridge
1576 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1577 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001578
1579config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001580 def_bool y
1581 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001582 depends on X86_64 && NUMA && ACPI && PCI
1583 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001584 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001585 Enable ACPI SRAT based node topology detection.
1586
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001587# Some NUMA nodes have memory ranges that span
1588# other nodes. Even though a pfn is valid and
1589# between a node's start and end pfns, it may not
1590# reside on that node. See memmap_init_zone()
1591# for details.
1592config NODES_SPAN_OTHER_NODES
1593 def_bool y
1594 depends on X86_64_ACPI_NUMA
1595
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001596config NUMA_EMU
1597 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001598 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001599 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001600 Enable NUMA emulation. A flat machine will be split
1601 into virtual nodes when booted with "numa=fake=N", where N is the
1602 number of nodes. This is only useful for debugging.
1603
1604config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001605 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001606 range 1 10
1607 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001608 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001609 default "3"
1610 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001611 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001612 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001613 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001614
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001615config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001616 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001617 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001618
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001619config ARCH_FLATMEM_ENABLE
1620 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001621 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001622
1623config ARCH_DISCONTIGMEM_ENABLE
Mike Rapoport27921072019-04-24 16:24:12 +03001624 def_bool n
Christoph Lameterb2632952008-01-30 13:30:47 +01001625 depends on NUMA && X86_32
Mike Rapoport27921072019-04-24 16:24:12 +03001626 depends on BROKEN
Christoph Lameterb2632952008-01-30 13:30:47 +01001627
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001628config ARCH_SPARSEMEM_ENABLE
1629 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001630 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001631 select SPARSEMEM_STATIC if X86_32
1632 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1633
Tejun Heo3b166512011-04-01 11:15:12 +02001634config ARCH_SPARSEMEM_DEFAULT
Mike Rapoport6ad57f72019-04-24 16:24:11 +03001635 def_bool X86_64 || (NUMA && X86_32)
Tejun Heo3b166512011-04-01 11:15:12 +02001636
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001637config ARCH_SELECT_MEMORY_MODEL
1638 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001639 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001640
1641config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001642 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001643 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001644 help
1645 This option enables a sysfs memory/probe interface for testing.
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001646 See Documentation/admin-guide/mm/memory-hotplug.rst for more information.
Toshi Kania0842b72013-07-19 11:47:48 -06001647 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001648
Tejun Heo3b166512011-04-01 11:15:12 +02001649config ARCH_PROC_KCORE_TEXT
1650 def_bool y
1651 depends on X86_64 && PROC_KCORE
1652
Avi Kivitya29815a2010-01-10 16:28:09 +02001653config ILLEGAL_POINTER_VALUE
1654 hex
1655 default 0 if X86_32
1656 default 0xdead000000000000 if X86_64
1657
Dan Williams7a678322015-08-19 00:34:34 -04001658config X86_PMEM_LEGACY_DEVICE
1659 bool
1660
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001661config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001662 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001663 depends on PHYS_ADDR_T_64BIT
1664 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001665 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001666 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001667 help
1668 Treat memory marked using the non-standard e820 type of 12 as used
1669 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1670 The kernel will offer these regions to the 'pmem' driver so
1671 they can be used for persistent storage.
1672
1673 Say Y if unsure.
1674
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001675config HIGHPTE
1676 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001677 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001678 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001679 The VM uses one page table entry for each page of physical memory.
1680 For systems with a lot of RAM, this can be wasteful of precious
1681 low memory. Setting this option will put user-space page table
1682 entries in high memory.
1683
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001684config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001685 bool "Check for low memory corruption"
1686 ---help---
1687 Periodically check for memory corruption in low memory, which
1688 is suspected to be caused by BIOS. Even when enabled in the
1689 configuration, it is disabled at runtime. Enable it by
1690 setting "memory_corruption_check=1" on the kernel command
1691 line. By default it scans the low 64k of memory every 60
1692 seconds; see the memory_corruption_check_size and
1693 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001694 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001695
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001696 When enabled with the default parameters, this option has
1697 almost no overhead, as it reserves a relatively small amount
1698 of memory and scans it infrequently. It both detects corruption
1699 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001700
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001701 It is, however, intended as a diagnostic tool; if repeatable
1702 BIOS-originated corruption always affects the same memory,
1703 you can use memmap= to prevent the kernel from using that
1704 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001705
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001706config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001707 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001708 depends on X86_CHECK_BIOS_CORRUPTION
1709 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001710 ---help---
1711 Set whether the default state of memory_corruption_check is
1712 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001713
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001714config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001715 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1716 default 64
1717 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001718 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001719 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001720
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001721 The first page contains BIOS data structures that the kernel
1722 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001723
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001724 By default we reserve the first 64K of physical RAM, as a
1725 number of BIOSes are known to corrupt that memory range
1726 during events such as suspend/resume or monitor cable
1727 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001728
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001729 You can set this to 4 if you are absolutely sure that you
1730 trust the BIOS to get all its memory reservations and usages
1731 right. If you know your BIOS have problems beyond the
1732 default 64K area, you can set this to 640 to avoid using the
1733 entire low memory range.
1734
1735 If you have doubts about the BIOS (e.g. suspend/resume does
1736 not work or there's kernel crashes after certain hardware
1737 hotplug events) then you might want to enable
1738 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1739 typical corruption patterns.
1740
1741 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001742
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001743config MATH_EMULATION
1744 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001745 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001746 prompt "Math emulation" if X86_32
1747 ---help---
1748 Linux can emulate a math coprocessor (used for floating point
1749 operations) if you don't have one. 486DX and Pentium processors have
1750 a math coprocessor built in, 486SX and 386 do not, unless you added
1751 a 487DX or 387, respectively. (The messages during boot time can
1752 give you some hints here ["man dmesg"].) Everyone needs either a
1753 coprocessor or this emulation.
1754
1755 If you don't have a math coprocessor, you need to say Y here; if you
1756 say Y here even though you have a coprocessor, the coprocessor will
1757 be used nevertheless. (This behavior can be changed with the kernel
1758 command line option "no387", which comes handy if your coprocessor
1759 is broken. Try "man bootparam" or see the documentation of your boot
1760 loader (lilo or loadlin) about how to pass options to the kernel at
1761 boot time.) This means that it is a good idea to say Y here if you
1762 intend to use this kernel on different machines.
1763
1764 More information about the internals of the Linux math coprocessor
1765 emulation can be found in <file:arch/x86/math-emu/README>.
1766
1767 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1768 kernel, it won't hurt.
1769
1770config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001771 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001772 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001773 ---help---
1774 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1775 the Memory Type Range Registers (MTRRs) may be used to control
1776 processor access to memory ranges. This is most useful if you have
1777 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1778 allows bus write transfers to be combined into a larger transfer
1779 before bursting over the PCI/AGP bus. This can increase performance
1780 of image write operations 2.5 times or more. Saying Y here creates a
1781 /proc/mtrr file which may be used to manipulate your processor's
1782 MTRRs. Typically the X server should use this.
1783
1784 This code has a reasonably generic interface so that similar
1785 control registers on other processors can be easily supported
1786 as well:
1787
1788 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1789 Registers (ARRs) which provide a similar functionality to MTRRs. For
1790 these, the ARRs are used to emulate the MTRRs.
1791 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1792 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1793 write-combining. All of these processors are supported by this code
1794 and it makes sense to say Y here if you have one of them.
1795
1796 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1797 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1798 can lead to all sorts of problems, so it's good to say Y here.
1799
1800 You can safely say Y even if your machine doesn't have MTRRs, you'll
1801 just add about 9 KB to your kernel.
1802
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001803 See <file:Documentation/x86/mtrr.rst> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001804
Yinghai Lu95ffa242008-04-29 03:52:33 -07001805config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001806 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001807 prompt "MTRR cleanup support"
1808 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001809 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001810 Convert MTRR layout from continuous to discrete, so X drivers can
1811 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001812
Thomas Gleixneraba37282008-07-15 14:48:48 +02001813 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001814 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001815 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001816
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001817 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001818
1819config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001820 int "MTRR cleanup enable value (0-1)"
1821 range 0 1
1822 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001823 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001824 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001825 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001826
Yinghai Lu12031a62008-05-02 02:40:22 -07001827config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1828 int "MTRR cleanup spare reg num (0-7)"
1829 range 0 7
1830 default "1"
1831 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001832 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001833 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001834 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001835
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001836config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001837 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001838 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001839 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001840 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001841 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001842
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001843 PATs are the modern equivalents of MTRRs and are much more
1844 flexible than MTRRs.
1845
1846 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001847 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001848
1849 If unsure, say Y.
1850
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001851config ARCH_USES_PG_UNCACHED
1852 def_bool y
1853 depends on X86_PAT
1854
H. Peter Anvin628c6242011-07-31 13:59:29 -07001855config ARCH_RANDOM
1856 def_bool y
1857 prompt "x86 architectural random number generator" if EXPERT
1858 ---help---
1859 Enable the x86 architectural RDRAND instruction
1860 (Intel Bull Mountain technology) to generate random numbers.
1861 If supported, this is a high bandwidth, cryptographically
1862 secure hardware random number generator.
1863
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001864config X86_SMAP
1865 def_bool y
1866 prompt "Supervisor Mode Access Prevention" if EXPERT
1867 ---help---
1868 Supervisor Mode Access Prevention (SMAP) is a security
1869 feature in newer Intel processors. There is a small
1870 performance cost if this enabled and turned on; there is
1871 also a small increase in the kernel size if this is enabled.
1872
1873 If unsure, say Y.
1874
Ricardo Neriaa35f892017-11-05 18:27:54 -08001875config X86_INTEL_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001876 def_bool y
Ricardo Neriaa35f892017-11-05 18:27:54 -08001877 depends on CPU_SUP_INTEL
1878 prompt "Intel User Mode Instruction Prevention" if EXPERT
1879 ---help---
1880 The User Mode Instruction Prevention (UMIP) is a security
1881 feature in newer Intel processors. If enabled, a general
Ricardo Neri796ebc82017-11-13 22:29:42 -08001882 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1883 or STR instructions are executed in user mode. These instructions
1884 unnecessarily expose information about the hardware state.
1885
1886 The vast majority of applications do not use these instructions.
1887 For the very few that do, software emulation is provided in
1888 specific cases in protected and virtual-8086 modes. Emulated
1889 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001890
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001891config X86_INTEL_MPX
1892 prompt "Intel MPX (Memory Protection Extensions)"
1893 def_bool n
Rik van Rieldf3735c2017-09-06 16:25:11 -07001894 # Note: only available in 64-bit mode due to VMA flags shortage
1895 depends on CPU_SUP_INTEL && X86_64
1896 select ARCH_USES_HIGH_VMA_FLAGS
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001897 ---help---
1898 MPX provides hardware features that can be used in
1899 conjunction with compiler-instrumented code to check
1900 memory references. It is designed to detect buffer
1901 overflow or underflow bugs.
1902
1903 This option enables running applications which are
1904 instrumented or otherwise use MPX. It does not use MPX
1905 itself inside the kernel or to protect the kernel
1906 against bad memory references.
1907
1908 Enabling this option will make the kernel larger:
1909 ~8k of kernel text and 36 bytes of data on a 64-bit
1910 defconfig. It adds a long to the 'mm_struct' which
1911 will increase the kernel memory overhead of each
1912 process and adds some branches to paths used during
1913 exec() and munmap().
1914
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001915 For details, see Documentation/x86/intel_mpx.rst
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001916
1917 If unsure, say N.
1918
Dave Hansen35e97792016-02-12 13:02:00 -08001919config X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001920 prompt "Intel Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001921 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001922 # Note: only available in 64-bit mode
Dave Hansen35e97792016-02-12 13:02:00 -08001923 depends on CPU_SUP_INTEL && X86_64
Ingo Molnar52c8e602016-11-15 10:15:03 +01001924 select ARCH_USES_HIGH_VMA_FLAGS
1925 select ARCH_HAS_PKEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001926 ---help---
1927 Memory Protection Keys provides a mechanism for enforcing
1928 page-based protections, but without requiring modification of the
1929 page tables when an application changes protection domains.
1930
Mauro Carvalho Chehab1eecbcd2019-06-07 15:54:31 -03001931 For details, see Documentation/core-api/protection-keys.rst
Dave Hansen284244a2016-02-12 13:02:28 -08001932
1933 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001934
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001935config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001936 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001937 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001938 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001939 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001940 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001941 This enables the kernel to use EFI runtime services that are
1942 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001943
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001944 This option is only useful on systems that have EFI firmware.
1945 In addition, you should use the latest ELILO loader available
1946 at <http://elilo.sourceforge.net> in order to take advantage
1947 of EFI runtime services. However, even with this option, the
1948 resultant kernel should continue to boot on existing non-EFI
1949 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001950
Matt Fleming291f3632011-12-12 21:27:52 +00001951config EFI_STUB
1952 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001953 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001954 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001955 ---help---
1956 This kernel feature allows a bzImage to be loaded directly
1957 by EFI firmware without the use of a bootloader.
1958
Mauro Carvalho Chehab4f4cfa62019-06-27 14:56:51 -03001959 See Documentation/admin-guide/efi-stub.rst for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001960
Matt Fleming7d453ee2014-01-10 18:52:06 +00001961config EFI_MIXED
1962 bool "EFI mixed-mode support"
1963 depends on EFI_STUB && X86_64
1964 ---help---
1965 Enabling this feature allows a 64-bit kernel to be booted
1966 on a 32-bit firmware, provided that your CPU supports 64-bit
1967 mode.
1968
1969 Note that it is not possible to boot a mixed-mode enabled
1970 kernel via the EFI boot stub - a bootloader that supports
1971 the EFI handover protocol must be used.
1972
1973 If unsure, say N.
1974
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001975config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001976 def_bool y
1977 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001978 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001979 This kernel feature is useful for number crunching applications
1980 that may need to compute untrusted bytecode during their
1981 execution. By using pipes or other transports made available to
1982 the process as file descriptors supporting the read/write
1983 syscalls, it's possible to isolate those applications in
1984 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001985 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001986 and the task is only allowed to execute a few safe syscalls
1987 defined by each seccomp mode.
1988
1989 If unsure, say Y. Only embedded should say N here.
1990
Masahiro Yamada8636a1f2018-12-11 20:01:04 +09001991source "kernel/Kconfig.hz"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001992
1993config KEXEC
1994 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001995 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001996 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001997 kexec is a system call that implements the ability to shutdown your
1998 current kernel, and to start another kernel. It is like a reboot
1999 but it is independent of the system firmware. And like a reboot
2000 you can start any kernel with it, not just Linux.
2001
2002 The name comes from the similarity to the exec system call.
2003
2004 It is an ongoing process to be certain the hardware in a machine
2005 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02002006 initially work for you. As of this writing the exact hardware
2007 interface is strongly in flux, so no good recommendation can be
2008 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002009
Vivek Goyal74ca3172014-08-29 15:18:46 -07002010config KEXEC_FILE
2011 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07002012 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07002013 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07002014 depends on X86_64
2015 depends on CRYPTO=y
2016 depends on CRYPTO_SHA256=y
2017 ---help---
2018 This is new version of kexec system call. This system call is
2019 file based and takes file descriptors as system call argument
2020 for kernel and initramfs as opposed to list of segments as
2021 accepted by previous system call.
2022
AKASHI Takahirob799a092018-04-13 15:35:45 -07002023config ARCH_HAS_KEXEC_PURGATORY
2024 def_bool KEXEC_FILE
2025
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002026config KEXEC_VERIFY_SIG
2027 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07002028 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002029 ---help---
2030 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002031 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002032
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002033 In addition to that option, you need to enable signature
2034 verification for the corresponding kernel image type being
2035 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002036
2037config KEXEC_BZIMAGE_VERIFY_SIG
2038 bool "Enable bzImage signature verification support"
2039 depends on KEXEC_VERIFY_SIG
2040 depends on SIGNED_PE_FILE_VERIFICATION
2041 select SYSTEM_TRUSTED_KEYRING
2042 ---help---
2043 Enable bzImage signature verification support.
2044
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002045config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002046 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002047 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002048 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002049 Generate crash dump after being started by kexec.
2050 This should be normally only set in special crash dump kernels
2051 which are loaded in the main kernel with kexec-tools into
2052 a specially reserved region and then later executed after
2053 a crash by kdump/kexec. The crash dump kernel must be compiled
2054 to a memory address not used by the main kernel or BIOS using
2055 PHYSICAL_START, or it must be built as a relocatable image
2056 (CONFIG_RELOCATABLE=y).
Mauro Carvalho Chehab330d4812019-06-13 15:21:39 -03002057 For more details see Documentation/admin-guide/kdump/kdump.rst
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002058
Huang Ying3ab83522008-07-25 19:45:07 -07002059config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002060 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002061 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002062 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07002063 Jump between original kernel and kexeced kernel and invoke
2064 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002065
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002066config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002067 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002068 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002069 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002070 This gives the physical address where the kernel is loaded.
2071
2072 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2073 bzImage will decompress itself to above physical address and
2074 run from there. Otherwise, bzImage will run from the address where
2075 it has been loaded by the boot loader and will ignore above physical
2076 address.
2077
2078 In normal kdump cases one does not have to set/change this option
2079 as now bzImage can be compiled as a completely relocatable image
2080 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2081 address. This option is mainly useful for the folks who don't want
2082 to use a bzImage for capturing the crash dump and want to use a
2083 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2084 to be specifically compiled to run from a specific memory area
2085 (normally a reserved region) and this option comes handy.
2086
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002087 So if you are using bzImage for capturing the crash dump,
2088 leave the value here unchanged to 0x1000000 and set
2089 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2090 for capturing the crash dump change this value to start of
2091 the reserved region. In other words, it can be set based on
2092 the "X" value as specified in the "crashkernel=YM@XM"
2093 command line boot parameter passed to the panic-ed
Mauro Carvalho Chehab330d4812019-06-13 15:21:39 -03002094 kernel. Please take a look at Documentation/admin-guide/kdump/kdump.rst
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002095 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002096
2097 Usage of bzImage for capturing the crash dump is recommended as
2098 one does not have to build two kernels. Same kernel can be used
2099 as production kernel and capture kernel. Above option should have
2100 gone away after relocatable bzImage support is introduced. But it
2101 is present because there are users out there who continue to use
2102 vmlinux for dump capture. This option should go away down the
2103 line.
2104
2105 Don't change this unless you know what you are doing.
2106
2107config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002108 bool "Build a relocatable kernel"
2109 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002110 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002111 This builds a kernel image that retains relocation information
2112 so it can be loaded someplace besides the default 1MB.
2113 The relocations tend to make the kernel binary about 10% larger,
2114 but are discarded at runtime.
2115
2116 One use is for the kexec on panic case where the recovery kernel
2117 must live at a different physical address than the primary
2118 kernel.
2119
2120 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2121 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002122 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002123
Kees Cook8ab38202013-10-10 17:18:14 -07002124config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002125 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002126 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002127 default y
Kees Cook8ab38202013-10-10 17:18:14 -07002128 ---help---
Baoquan Hee8581e32016-04-20 13:55:43 -07002129 In support of Kernel Address Space Layout Randomization (KASLR),
2130 this randomizes the physical address at which the kernel image
2131 is decompressed and the virtual address where the kernel
2132 image is mapped, as a security feature that deters exploit
2133 attempts relying on knowledge of the location of kernel
2134 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002135
Kees Cooked9f0072016-05-25 15:45:33 -07002136 On 64-bit, the kernel physical and virtual addresses are
2137 randomized separately. The physical address will be anywhere
2138 between 16MB and the top of physical memory (up to 64TB). The
2139 virtual address will be randomized from 16MB up to 1GB (9 bits
2140 of entropy). Note that this also reduces the memory space
2141 available to kernel modules from 1.5GB to 1GB.
2142
2143 On 32-bit, the kernel physical and virtual addresses are
2144 randomized together. They will be randomized from 16MB up to
2145 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002146
Baoquan Hee8581e32016-04-20 13:55:43 -07002147 Entropy is generated using the RDRAND instruction if it is
2148 supported. If RDTSC is supported, its value is mixed into
2149 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002150 supported, then entropy is read from the i8254 timer. The
2151 usable entropy is limited by the kernel being built using
2152 2GB addressing, and that PHYSICAL_ALIGN must be at a
2153 minimum of 2MB. As a result, only 10 bits of entropy are
2154 theoretically possible, but the implementations are further
2155 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002156
Ingo Molnar6807c842017-04-18 11:08:12 +02002157 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002158
2159# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002160config X86_NEED_RELOCS
2161 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002162 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002163
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002164config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002165 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002166 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002167 range 0x2000 0x1000000 if X86_32
2168 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002169 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002170 This value puts the alignment restrictions on physical address
2171 where kernel is loaded and run from. Kernel is compiled for an
2172 address which meets above alignment restriction.
2173
2174 If bootloader loads the kernel at a non-aligned address and
2175 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2176 address aligned to above value and run from there.
2177
2178 If bootloader loads the kernel at a non-aligned address and
2179 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2180 load address and decompress itself to the address it has been
2181 compiled for and run from there. The address for which kernel is
2182 compiled already meets above alignment restrictions. Hence the
2183 end result is that kernel runs from a physical address meeting
2184 above alignment restrictions.
2185
Kees Cooka0215062013-07-08 09:15:17 -07002186 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2187 this value must be a multiple of 0x200000.
2188
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002189 Don't change this unless you know what you are doing.
2190
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002191config DYNAMIC_MEMORY_LAYOUT
2192 bool
2193 ---help---
2194 This option makes base addresses of vmalloc and vmemmap as well as
2195 __PAGE_OFFSET movable during boot.
2196
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002197config RANDOMIZE_MEMORY
2198 bool "Randomize the kernel memory sections"
2199 depends on X86_64
2200 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002201 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002202 default RANDOMIZE_BASE
2203 ---help---
2204 Randomizes the base virtual address of kernel memory sections
2205 (physical memory mapping, vmalloc & vmemmap). This security feature
2206 makes exploits relying on predictable memory locations less reliable.
2207
2208 The order of allocations remains unchanged. Entropy is generated in
2209 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2210 configuration have in average 30,000 different possible virtual
2211 addresses for each memory section.
2212
Ingo Molnar6807c842017-04-18 11:08:12 +02002213 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002214
Thomas Garnier90397a42016-06-21 17:47:06 -07002215config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2216 hex "Physical memory mapping padding" if EXPERT
2217 depends on RANDOMIZE_MEMORY
2218 default "0xa" if MEMORY_HOTPLUG
2219 default "0x0"
2220 range 0x1 0x40 if MEMORY_HOTPLUG
2221 range 0x0 0x40
2222 ---help---
2223 Define the padding in terabytes added to the existing physical
2224 memory size during kernel memory randomization. It is useful
2225 for memory hotplug support but reduces the entropy available for
2226 address randomization.
2227
2228 If unsure, leave at the default value.
2229
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002230config HOTPLUG_CPU
Thomas Gleixnerbebd0242019-03-26 17:36:06 +01002231 def_bool y
Stephen Rothwell40b31362013-05-21 13:49:35 +10002232 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002233
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002234config BOOTPARAM_HOTPLUG_CPU0
2235 bool "Set default setting of cpu0_hotpluggable"
Kees Cook2c922cd2013-01-22 13:01:19 -08002236 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002237 ---help---
2238 Set whether default state of cpu0_hotpluggable is on or off.
2239
2240 Say Y here to enable CPU0 hotplug by default. If this switch
2241 is turned on, there is no need to give cpu0_hotplug kernel
2242 parameter and the CPU0 hotplug feature is enabled by default.
2243
2244 Please note: there are two known CPU0 dependencies if you want
2245 to enable the CPU0 hotplug feature either by this switch or by
2246 cpu0_hotplug kernel parameter.
2247
2248 First, resume from hibernate or suspend always starts from CPU0.
2249 So hibernate and suspend are prevented if CPU0 is offline.
2250
2251 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2252 offline if any interrupt can not migrate out of CPU0. There may
2253 be other CPU0 dependencies.
2254
2255 Please make sure the dependencies are under your control before
2256 you enable this feature.
2257
2258 Say N if you don't want to enable CPU0 hotplug feature by default.
2259 You still can enable the CPU0 hotplug feature at boot by kernel
2260 parameter cpu0_hotplug.
2261
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002262config DEBUG_HOTPLUG_CPU0
2263 def_bool n
2264 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002265 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002266 ---help---
2267 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2268 soon as possible and boots up userspace with CPU0 offlined. User
2269 can online CPU0 back after boot time.
2270
2271 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2272 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2273 compilation or giving cpu0_hotplug kernel parameter at boot.
2274
2275 If unsure, say N.
2276
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002277config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002278 def_bool n
2279 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002280 depends on COMPAT_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002281 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002282 Certain buggy versions of glibc will crash if they are
2283 presented with a 32-bit vDSO that is not mapped at the address
2284 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002285
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002286 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2287 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2288 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2289 the only released version with the bug, but OpenSUSE 9
2290 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002291
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002292 The symptom of the bug is that everything crashes on startup, saying:
2293 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2294
2295 Saying Y here changes the default value of the vdso32 boot
2296 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2297 This works around the glibc bug but hurts performance.
2298
2299 If unsure, say N: if you are compiling your own kernel, you
2300 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002301
Kees Cook3dc33bd2015-08-12 17:55:19 -07002302choice
2303 prompt "vsyscall table for legacy applications"
2304 depends on X86_64
Andy Lutomirski625b7b72019-06-26 21:45:07 -07002305 default LEGACY_VSYSCALL_XONLY
Kees Cook3dc33bd2015-08-12 17:55:19 -07002306 help
2307 Legacy user code that does not know how to find the vDSO expects
2308 to be able to issue three syscalls by calling fixed addresses in
2309 kernel space. Since this location is not randomized with ASLR,
2310 it can be used to assist security vulnerability exploitation.
2311
2312 This setting can be changed at boot time via the kernel command
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002313 line parameter vsyscall=[emulate|xonly|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002314
2315 On a system with recent enough glibc (2.14 or newer) and no
2316 static binaries, you can say None without a performance penalty
2317 to improve security.
2318
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002319 If unsure, select "Emulate execution only".
Kees Cook3dc33bd2015-08-12 17:55:19 -07002320
Kees Cook3dc33bd2015-08-12 17:55:19 -07002321 config LEGACY_VSYSCALL_EMULATE
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002322 bool "Full emulation"
Kees Cook3dc33bd2015-08-12 17:55:19 -07002323 help
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002324 The kernel traps and emulates calls into the fixed vsyscall
2325 address mapping. This makes the mapping non-executable, but
2326 it still contains readable known contents, which could be
2327 used in certain rare security vulnerability exploits. This
2328 configuration is recommended when using legacy userspace
2329 that still uses vsyscalls along with legacy binary
2330 instrumentation tools that require code to be readable.
2331
2332 An example of this type of legacy userspace is running
2333 Pin on an old binary that still uses vsyscalls.
2334
2335 config LEGACY_VSYSCALL_XONLY
2336 bool "Emulate execution only"
2337 help
2338 The kernel traps and emulates calls into the fixed vsyscall
2339 address mapping and does not allow reads. This
2340 configuration is recommended when userspace might use the
2341 legacy vsyscall area but support for legacy binary
2342 instrumentation of legacy code is not needed. It mitigates
2343 certain uses of the vsyscall area as an ASLR-bypassing
2344 buffer.
Kees Cook3dc33bd2015-08-12 17:55:19 -07002345
2346 config LEGACY_VSYSCALL_NONE
2347 bool "None"
2348 help
2349 There will be no vsyscall mapping at all. This will
2350 eliminate any risk of ASLR bypass due to the vsyscall
2351 fixed address mapping. Attempts to use the vsyscalls
2352 will be reported to dmesg, so that either old or
2353 malicious userspace programs can be identified.
2354
2355endchoice
2356
Tim Bird516cbf32008-08-12 12:52:36 -07002357config CMDLINE_BOOL
2358 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002359 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002360 Allow for specifying boot arguments to the kernel at
2361 build time. On some systems (e.g. embedded ones), it is
2362 necessary or convenient to provide some or all of the
2363 kernel boot arguments with the kernel itself (that is,
2364 to not rely on the boot loader to provide them.)
2365
2366 To compile command line arguments into the kernel,
2367 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002368 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002369
2370 Systems with fully functional boot loaders (i.e. non-embedded)
2371 should leave this option set to 'N'.
2372
2373config CMDLINE
2374 string "Built-in kernel command string"
2375 depends on CMDLINE_BOOL
2376 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002377 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002378 Enter arguments here that should be compiled into the kernel
2379 image and used at boot time. If the boot loader provides a
2380 command line at boot time, it is appended to this string to
2381 form the full kernel command line, when the system boots.
2382
2383 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2384 change this behavior.
2385
2386 In most cases, the command line (whether built-in or provided
2387 by the boot loader) should specify the device for the root
2388 file system.
2389
2390config CMDLINE_OVERRIDE
2391 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002392 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002393 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002394 Set this option to 'Y' to have the kernel ignore the boot loader
2395 command line, and use ONLY the built-in command line.
2396
2397 This is used to work around broken boot loaders. This should
2398 be set to 'N' under normal conditions.
2399
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002400config MODIFY_LDT_SYSCALL
2401 bool "Enable the LDT (local descriptor table)" if EXPERT
2402 default y
2403 ---help---
2404 Linux can allow user programs to install a per-process x86
2405 Local Descriptor Table (LDT) using the modify_ldt(2) system
2406 call. This is required to run 16-bit or segmented code such as
2407 DOSEMU or some Wine programs. It is also used by some very old
2408 threading libraries.
2409
2410 Enabling this feature adds a small amount of overhead to
2411 context switches and increases the low-level kernel attack
2412 surface. Disabling it removes the modify_ldt(2) system call.
2413
2414 Saying 'N' here may make sense for embedded or server kernels.
2415
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002416source "kernel/livepatch/Kconfig"
2417
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002418endmenu
2419
Michal Hocko3072e412017-09-08 16:11:39 -07002420config ARCH_HAS_ADD_PAGES
2421 def_bool y
2422 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2423
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002424config ARCH_ENABLE_MEMORY_HOTPLUG
2425 def_bool y
2426 depends on X86_64 || (X86_32 && HIGHMEM)
2427
Gary Hade35551052008-10-31 10:52:03 -07002428config ARCH_ENABLE_MEMORY_HOTREMOVE
2429 def_bool y
2430 depends on MEMORY_HOTPLUG
2431
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002432config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002433 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002434 depends on NUMA
2435
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002436config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2437 def_bool y
2438 depends on X86_64 || X86_PAE
2439
Naoya Horiguchic177c812014-06-04 16:05:35 -07002440config ARCH_ENABLE_HUGEPAGE_MIGRATION
2441 def_bool y
2442 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2443
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002444config ARCH_ENABLE_THP_MIGRATION
2445 def_bool y
2446 depends on X86_64 && TRANSPARENT_HUGEPAGE
2447
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002448menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002449
2450config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002451 def_bool y
Zhimin Gu44556532018-09-21 14:27:29 +08002452 depends on HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002453
2454source "kernel/power/Kconfig"
2455
2456source "drivers/acpi/Kconfig"
2457
Feng Tangefafc8b2009-08-14 15:23:29 -04002458source "drivers/sfi/Kconfig"
2459
Andi Kleena6b68072008-01-30 13:32:49 +01002460config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002461 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002462 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002463
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002464menuconfig APM
2465 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002466 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002467 ---help---
2468 APM is a BIOS specification for saving power using several different
2469 techniques. This is mostly useful for battery powered laptops with
2470 APM compliant BIOSes. If you say Y here, the system time will be
2471 reset after a RESUME operation, the /proc/apm device will provide
2472 battery status information, and user-space programs will receive
2473 notification of APM "events" (e.g. battery status change).
2474
2475 If you select "Y" here, you can disable actual use of the APM
2476 BIOS by passing the "apm=off" option to the kernel at boot time.
2477
2478 Note that the APM support is almost completely disabled for
2479 machines with more than one CPU.
2480
2481 In order to use APM, you will need supporting software. For location
Mauro Carvalho Chehab151f4e22019-06-13 07:10:36 -03002482 and more information, read <file:Documentation/power/apm-acpi.rst>
Michael Witten2dc98fd2011-07-08 21:11:16 +00002483 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002484 <http://www.tldp.org/docs.html#howto>.
2485
2486 This driver does not spin down disk drives (see the hdparm(8)
2487 manpage ("man 8 hdparm") for that), and it doesn't turn off
2488 VESA-compliant "green" monitors.
2489
2490 This driver does not support the TI 4000M TravelMate and the ACER
2491 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2492 desktop machines also don't have compliant BIOSes, and this driver
2493 may cause those machines to panic during the boot phase.
2494
2495 Generally, if you don't have a battery in your machine, there isn't
2496 much point in using this driver and you should say N. If you get
2497 random kernel OOPSes or reboots that don't seem to be related to
2498 anything, try disabling/enabling this option (or disabling/enabling
2499 APM in your BIOS).
2500
2501 Some other things you should try when experiencing seemingly random,
2502 "weird" problems:
2503
2504 1) make sure that you have enough swap space and that it is
2505 enabled.
2506 2) pass the "no-hlt" option to the kernel
2507 3) switch on floating point emulation in the kernel and pass
2508 the "no387" option to the kernel
2509 4) pass the "floppy=nodma" option to the kernel
2510 5) pass the "mem=4M" option to the kernel (thereby disabling
2511 all but the first 4 MB of RAM)
2512 6) make sure that the CPU is not over clocked.
2513 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2514 8) disable the cache from your BIOS settings
2515 9) install a fan for the video card or exchange video RAM
2516 10) install a better fan for the CPU
2517 11) exchange RAM chips
2518 12) exchange the motherboard.
2519
2520 To compile this driver as a module, choose M here: the
2521 module will be called apm.
2522
2523if APM
2524
2525config APM_IGNORE_USER_SUSPEND
2526 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002527 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002528 This option will ignore USER SUSPEND requests. On machines with a
2529 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2530 series notebooks, it is necessary to say Y because of a BIOS bug.
2531
2532config APM_DO_ENABLE
2533 bool "Enable PM at boot time"
2534 ---help---
2535 Enable APM features at boot time. From page 36 of the APM BIOS
2536 specification: "When disabled, the APM BIOS does not automatically
2537 power manage devices, enter the Standby State, enter the Suspend
2538 State, or take power saving steps in response to CPU Idle calls."
2539 This driver will make CPU Idle calls when Linux is idle (unless this
2540 feature is turned off -- see "Do CPU IDLE calls", below). This
2541 should always save battery power, but more complicated APM features
2542 will be dependent on your BIOS implementation. You may need to turn
2543 this option off if your computer hangs at boot time when using APM
2544 support, or if it beeps continuously instead of suspending. Turn
2545 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2546 T400CDT. This is off by default since most machines do fine without
2547 this feature.
2548
2549config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002550 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002551 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002552 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002553 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2554 On some machines, this can activate improved power savings, such as
2555 a slowed CPU clock rate, when the machine is idle. These idle calls
2556 are made after the idle loop has run for some length of time (e.g.,
2557 333 mS). On some machines, this will cause a hang at boot time or
2558 whenever the CPU becomes idle. (On machines with more than one CPU,
2559 this option does nothing.)
2560
2561config APM_DISPLAY_BLANK
2562 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002563 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002564 Enable console blanking using the APM. Some laptops can use this to
2565 turn off the LCD backlight when the screen blanker of the Linux
2566 virtual console blanks the screen. Note that this is only used by
2567 the virtual console screen blanker, and won't turn off the backlight
2568 when using the X Window system. This also doesn't have anything to
2569 do with your VESA-compliant power-saving monitor. Further, this
2570 option doesn't work for all laptops -- it might not turn off your
2571 backlight at all, or it might print a lot of errors to the console,
2572 especially if you are using gpm.
2573
2574config APM_ALLOW_INTS
2575 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002576 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002577 Normally we disable external interrupts while we are making calls to
2578 the APM BIOS as a measure to lessen the effects of a badly behaving
2579 BIOS implementation. The BIOS should reenable interrupts if it
2580 needs to. Unfortunately, some BIOSes do not -- especially those in
2581 many of the newer IBM Thinkpads. If you experience hangs when you
2582 suspend, try setting this to Y. Otherwise, say N.
2583
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002584endif # APM
2585
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002586source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002587
2588source "drivers/cpuidle/Kconfig"
2589
Andy Henroid27471fd2008-10-09 11:45:22 -07002590source "drivers/idle/Kconfig"
2591
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002592endmenu
2593
2594
2595menu "Bus options (PCI etc.)"
2596
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002597choice
2598 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002599 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002600 default PCI_GOANY
2601 ---help---
2602 On PCI systems, the BIOS can be used to detect the PCI devices and
2603 determine their configuration. However, some old PCI motherboards
2604 have BIOS bugs and may crash if this is done. Also, some embedded
2605 PCI-based systems don't have any BIOS at all. Linux can also try to
2606 detect the PCI hardware directly without using the BIOS.
2607
2608 With this option, you can specify how Linux should detect the
2609 PCI devices. If you choose "BIOS", the BIOS will be used,
2610 if you choose "Direct", the BIOS won't be used, and if you
2611 choose "MMConfig", then PCI Express MMCONFIG will be used.
2612 If you choose "Any", the kernel will try MMCONFIG, then the
2613 direct access method and falls back to the BIOS if that doesn't
2614 work. If unsure, go with the default, which is "Any".
2615
2616config PCI_GOBIOS
2617 bool "BIOS"
2618
2619config PCI_GOMMCONFIG
2620 bool "MMConfig"
2621
2622config PCI_GODIRECT
2623 bool "Direct"
2624
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002625config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002626 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002627 depends on OLPC
2628
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002629config PCI_GOANY
2630 bool "Any"
2631
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002632endchoice
2633
2634config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002635 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002636 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002637
2638# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2639config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002640 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002641 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002642
2643config PCI_MMCONFIG
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002644 bool "Support mmconfig PCI config space access" if X86_64
2645 default y
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002646 depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002647 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002648
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002649config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002650 def_bool y
2651 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002652
Alex Nixonb5401a92010-03-18 16:31:34 -04002653config PCI_XEN
2654 def_bool y
2655 depends on PCI && XEN
2656 select SWIOTLB_XEN
2657
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002658config MMCONF_FAM10H
2659 def_bool y
2660 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002661
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002662config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002663 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002664 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002665 help
2666 Read the PCI windows out of the CNB20LE host bridge. This allows
2667 PCI hotplug to work on systems with the CNB20LE chipset which do
2668 not have ACPI.
2669
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002670 There's no public spec for this chipset, and this functionality
2671 is known to be incomplete.
2672
2673 You should say N unless you know you need this.
2674
William Breathitt Gray3a495512016-05-27 18:08:27 -04002675config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002676 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002677 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002678 Expose ISA bus device drivers and options available for selection and
2679 configuration. Enable this option if your target machine has an ISA
2680 bus. ISA is an older system, displaced by PCI and newer bus
2681 architectures -- if your target machine is modern, it probably does
2682 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002683
2684 If unsure, say N.
2685
David Rientjes1c00f012011-03-22 16:34:59 -07002686# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002687config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002688 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2689 default y
2690 help
2691 Enables ISA-style DMA support for devices requiring such controllers.
2692 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002693
Linus Torvalds51e68d02016-05-21 10:25:19 -07002694if X86_32
2695
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002696config ISA
2697 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002698 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002699 Find out whether you have ISA slots on your motherboard. ISA is the
2700 name of a bus system, i.e. the way the CPU talks to the other stuff
2701 inside your box. Other bus systems are PCI, EISA, MicroChannel
2702 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2703 newer boards don't support it. If you have ISA, say Y, otherwise N.
2704
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002705config SCx200
2706 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002707 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002708 This provides basic support for National Semiconductor's
2709 (now AMD's) Geode processors. The driver probes for the
2710 PCI-IDs of several on-chip devices, so its a good dependency
2711 for other scx200_* drivers.
2712
2713 If compiled as a module, the driver is named scx200.
2714
2715config SCx200HR_TIMER
2716 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002717 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002718 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002719 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002720 This driver provides a clocksource built upon the on-chip
2721 27MHz high-resolution timer. Its also a workaround for
2722 NSC Geode SC-1100's buggy TSC, which loses time when the
2723 processor goes idle (as is done by the scheduler). The
2724 other workaround is idle=poll boot option.
2725
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002726config OLPC
2727 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002728 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002729 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002730 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002731 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002732 select IRQ_DOMAIN
Lubomir Rintel0c3d9312019-05-13 09:56:37 +02002733 select OLPC_EC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002734 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002735 Add support for detecting the unique features of the OLPC
2736 XO hardware.
2737
Daniel Drakea3128582011-06-25 17:34:10 +01002738config OLPC_XO1_PM
2739 bool "OLPC XO-1 Power Management"
Borislav Petkovfa112cf2018-10-05 15:13:07 +02002740 depends on OLPC && MFD_CS5535=y && PM_SLEEP
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002741 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002742 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002743
Daniel Drakecfee9592011-06-25 17:34:17 +01002744config OLPC_XO1_RTC
2745 bool "OLPC XO-1 Real Time Clock"
2746 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2747 ---help---
2748 Add support for the XO-1 real time clock, which can be used as a
2749 programmable wakeup source.
2750
Daniel Drake7feda8e2011-06-25 17:34:12 +01002751config OLPC_XO1_SCI
2752 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002753 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002754 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002755 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002756 ---help---
2757 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002758 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002759 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002760 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002761 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002762 - AC adapter status updates
2763 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002764
Daniel Drakea0f30f52011-06-25 17:34:18 +01002765config OLPC_XO15_SCI
2766 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002767 depends on OLPC && ACPI
2768 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002769 ---help---
2770 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2771 - EC-driven system wakeups
2772 - AC adapter status updates
2773 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002774
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002775config ALIX
2776 bool "PCEngines ALIX System Support (LED setup)"
2777 select GPIOLIB
2778 ---help---
2779 This option enables system support for the PCEngines ALIX.
2780 At present this just sets up LEDs for GPIO control on
2781 ALIX2/3/6 boards. However, other system specific setup should
2782 get added here.
2783
2784 Note: You must still enable the drivers for GPIO and LED support
2785 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2786
2787 Note: You have to set alix.force=1 for boards with Award BIOS.
2788
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002789config NET5501
2790 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2791 select GPIOLIB
2792 ---help---
2793 This option enables system support for the Soekris Engineering net5501.
2794
Philip A. Prindeville31970592012-01-14 01:45:39 -07002795config GEOS
2796 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2797 select GPIOLIB
2798 depends on DMI
2799 ---help---
2800 This option enables system support for the Traverse Technologies GEOS.
2801
Vivien Didelot7d029122013-01-04 16:18:14 -05002802config TS5500
2803 bool "Technologic Systems TS-5500 platform support"
2804 depends on MELAN
2805 select CHECK_SIGNATURE
2806 select NEW_LEDS
2807 select LEDS_CLASS
2808 ---help---
2809 This option enables system support for the Technologic Systems TS-5500.
2810
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002811endif # X86_32
2812
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002813config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002814 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002815 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002816
David Herrmanne3263ab2013-08-02 14:05:22 +02002817config X86_SYSFB
2818 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2819 help
2820 Firmwares often provide initial graphics framebuffers so the BIOS,
2821 bootloader or kernel can show basic video-output during boot for
2822 user-guidance and debugging. Historically, x86 used the VESA BIOS
2823 Extensions and EFI-framebuffers for this, which are mostly limited
2824 to x86.
2825 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2826 framebuffers so the new generic system-framebuffer drivers can be
2827 used on x86. If the framebuffer is not compatible with the generic
Nikolas Nybye3a5dc02018-08-25 19:10:54 -04002828 modes, it is advertised as fallback platform framebuffer so legacy
David Herrmanne3263ab2013-08-02 14:05:22 +02002829 drivers like efifb, vesafb and uvesafb can pick it up.
2830 If this option is not selected, all system framebuffers are always
2831 marked as fallback platform framebuffers as usual.
2832
2833 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2834 not be able to pick up generic system framebuffers if this option
2835 is selected. You are highly encouraged to enable simplefb as
2836 replacement if you select this option. simplefb can correctly deal
2837 with generic system framebuffers. But you should still keep vesafb
2838 and others enabled as fallback if a system framebuffer is
2839 incompatible with simplefb.
2840
2841 If unsure, say Y.
2842
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002843endmenu
2844
2845
Christoph Hellwig15724972018-07-31 13:39:30 +02002846menu "Binary Emulations"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002847
2848config IA32_EMULATION
2849 bool "IA32 Emulation"
2850 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002851 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002852 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002853 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002854 select COMPAT_OLD_SIGACTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002855 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002856 Include code to run legacy 32-bit programs under a
2857 64-bit kernel. You should likely turn this on, unless you're
2858 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002859
2860config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002861 tristate "IA32 a.out support"
2862 depends on IA32_EMULATION
Borislav Petkoveac61652019-03-05 15:47:51 +01002863 depends on BROKEN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002864 ---help---
2865 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002866
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002867config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002868 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002869 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002870 ---help---
2871 Include code to run binaries for the x32 native 32-bit ABI
2872 for 64-bit processors. An x32 process gets access to the
2873 full 64-bit register file and wide data path while leaving
2874 pointers at 32 bits for smaller memory footprint.
2875
2876 You will need a recent binutils (2.22 or later) with
2877 elf32_x86_64 support enabled to compile a kernel with this
2878 option set.
2879
Ingo Molnar953fee12016-11-15 10:22:52 +01002880config COMPAT_32
2881 def_bool y
2882 depends on IA32_EMULATION || X86_32
2883 select HAVE_UID16
2884 select OLD_SIGSUSPEND3
2885
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002886config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002887 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002888 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002889
Jan Beulich3120e252012-09-10 12:41:45 +01002890if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002891config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002892 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002893
2894config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002895 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002896 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002897endif
David Howellsee009e4a02011-03-07 15:06:20 +00002898
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002899endmenu
2900
2901
Keith Packarde5beae12008-11-03 18:21:45 +01002902config HAVE_ATOMIC_IOMAP
2903 def_bool y
2904 depends on X86_32
2905
Alessandro Rubini4692d772012-04-04 19:39:58 +02002906config X86_DEV_DMA_OPS
2907 bool
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002908
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002909source "drivers/firmware/Kconfig"
2910
Avi Kivityedf88412007-12-16 11:02:48 +02002911source "arch/x86/kvm/Kconfig"