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Greg Kroah-Hartmanb2441312017-11-01 15:07:57 +01001# SPDX-License-Identifier: GPL-2.0
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01002# Select 32 or 64 bit
3config 64BIT
Masahiro Yamada104daea2018-05-28 18:21:40 +09004 bool "64-bit kernel" if "$(ARCH)" = "x86"
5 default "$(ARCH)" != "i386"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01006 ---help---
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01007 Say yes to build a 64-bit kernel - formerly known as x86_64
8 Say no to build a 32-bit kernel - formerly known as i386
9
10config X86_32
Jan Beulich3120e252012-09-10 12:41:45 +010011 def_bool y
12 depends on !64BIT
Ingo Molnar341c7872016-11-15 10:04:55 +010013 # Options that are inherently 32-bit kernel only:
14 select ARCH_WANT_IPC_PARSE_VERSION
15 select CLKSRC_I8253
16 select CLONE_BACKWARDS
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
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +010020
21config X86_64
Jan Beulich3120e252012-09-10 12:41:45 +010022 def_bool y
23 depends on 64BIT
Ingo Molnard94e0682016-11-15 10:11:57 +010024 # Options that are inherently 64-bit kernel only:
Alexandre Ghiti4eb07162019-05-13 17:19:04 -070025 select ARCH_HAS_GIGANTIC_PAGE
Ingo Molnard94e0682016-11-15 10:11:57 +010026 select ARCH_SUPPORTS_INT128
27 select ARCH_USE_CMPXCHG_LOCKREF
28 select HAVE_ARCH_SOFT_DIRTY
29 select MODULES_USE_ELF_RELA
Christoph Hellwigf616ab52018-05-09 06:53:49 +020030 select NEED_DMA_MAP_STATE
Christoph Hellwig09230cb2018-04-24 09:00:54 +020031 select SWIOTLB
Dominik Brodowskif8781c42018-04-05 11:53:05 +020032 select ARCH_HAS_SYSCALL_WRAPPER
Sam Ravnborg1032c0b2007-11-06 21:35:08 +010033
Steven Rostedt (VMware)518049d2019-05-10 12:05:46 -040034config FORCE_DYNAMIC_FTRACE
35 def_bool y
36 depends on X86_32
37 depends on FUNCTION_TRACER
38 select DYNAMIC_FTRACE
39 help
40 We keep the static function tracing (!DYNAMIC_FTRACE) around
41 in order to test the non static function tracing in the
42 generic code, as other architectures still use it. But we
43 only need to keep it around for x86_64. No need to keep it
44 for x86_32. For x86_32, force DYNAMIC_FTRACE.
Ingo Molnard94e0682016-11-15 10:11:57 +010045#
46# Arch settings
47#
48# ( Note that options that are marked 'if X86_64' could in principle be
49# ported to 32-bit as well. )
50#
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +010051config X86
Harvey Harrison3c2362e2008-01-30 13:31:03 +010052 def_bool y
Ingo Molnarc763ea22016-11-15 10:26:39 +010053 #
54 # Note: keep this list sorted alphabetically
55 #
Ingo Molnar6471b822015-06-03 10:00:13 +020056 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
57 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
Yury Norov942fa982018-05-16 11:18:49 +030058 select ARCH_32BIT_OFF_T if X86_32
Ingo Molnar6471b822015-06-03 10:00:13 +020059 select ARCH_CLOCKSOURCE_DATA
Thomas Gleixner2a21ad52018-09-17 14:45:35 +020060 select ARCH_CLOCKSOURCE_INIT
Ingo Molnarc763ea22016-11-15 10:26:39 +010061 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
Laura Abbottfa5b6ec2017-01-10 13:35:40 -080062 select ARCH_HAS_DEBUG_VIRTUAL
Dan Williams21266be2015-11-19 18:19:29 -080063 select ARCH_HAS_DEVMEM_IS_ALLOWED
Ingo Molnar6471b822015-06-03 10:00:13 +020064 select ARCH_HAS_ELF_RANDOMIZE
Linus Torvalds72d93102014-09-13 11:14:53 -070065 select ARCH_HAS_FAST_MULTIPLIER
Dave Hansen316d0972018-04-20 15:20:28 -070066 select ARCH_HAS_FILTER_PGPROT
Daniel Micay6974f0c2017-07-12 14:36:10 -070067 select ARCH_HAS_FORTIFY_SOURCE
Riku Voipio957e3fa2014-12-12 16:57:44 -080068 select ARCH_HAS_GCOV_PROFILE_ALL
Dmitry Vyukov5c9a8752016-03-22 14:27:30 -070069 select ARCH_HAS_KCOV if X86_64
Mathieu Desnoyers10bcc802018-01-29 15:20:18 -050070 select ARCH_HAS_MEMBARRIER_SYNC_CORE
Ingo Molnarc763ea22016-11-15 10:26:39 +010071 select ARCH_HAS_PMEM_API if X86_64
Laurent Dufour3010a5e2018-06-07 17:06:08 -070072 select ARCH_HAS_PTE_SPECIAL
Kees Cook39208aa2017-09-02 13:09:46 -070073 select ARCH_HAS_REFCOUNT
Dan Williams0aed55a2017-05-29 12:22:50 -070074 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Dan Williams092b31a2018-07-08 13:46:17 -070075 select ARCH_HAS_UACCESS_MCSAFE if X86_64 && X86_MCE
Daniel Borkmannd2852a22017-02-21 16:09:33 +010076 select ARCH_HAS_SET_MEMORY
Rick Edgecombed253ca02019-04-25 17:11:34 -070077 select ARCH_HAS_SET_DIRECT_MAP
Laura Abbottad21fc42017-02-06 16:31:57 -080078 select ARCH_HAS_STRICT_KERNEL_RWX
79 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050080 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Andrey Ryabininc6d30852016-01-20 15:00:55 -080081 select ARCH_HAS_UBSAN_SANITIZE_ALL
Oliver O'Halloran65f7d042017-06-28 11:32:31 +100082 select ARCH_HAS_ZONE_DEVICE if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020083 select ARCH_HAVE_NMI_SAFE_CMPXCHG
84 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040085 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080086 select ARCH_MIGHT_HAVE_PC_SERIO
Thomas Gleixner3599fe12019-04-25 11:45:22 +020087 select ARCH_STACKWALK
Arnd Bergmann2c870e62018-07-24 11:48:45 +020088 select ARCH_SUPPORTS_ACPI
Ingo Molnar6471b822015-06-03 10:00:13 +020089 select ARCH_SUPPORTS_ATOMIC_RMW
Ingo Molnar6471b822015-06-03 10:00:13 +020090 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
91 select ARCH_USE_BUILTIN_BSWAP
Ingo Molnar6471b822015-06-03 10:00:13 +020092 select ARCH_USE_QUEUED_RWLOCKS
93 select ARCH_USE_QUEUED_SPINLOCKS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -070094 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Ingo Molnarc763ea22016-11-15 10:26:39 +010095 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Huang Ying38d8b4e2017-07-06 15:37:18 -070096 select ARCH_WANTS_THP_SWAP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +020097 select BUILDTIME_EXTABLE_SORT
98 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +020099 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
100 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +0200101 select DCACHE_WORD_ACCESS
Linus Torvalds45471cd2015-06-24 19:52:06 -0700102 select EDAC_ATOMIC_SCRUB
103 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +0200104 select GENERIC_CLOCKEVENTS
105 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
106 select GENERIC_CLOCKEVENTS_MIN_ADJUST
107 select GENERIC_CMOS_UPDATE
108 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +0100109 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +0200110 select GENERIC_EARLY_IOREMAP
111 select GENERIC_FIND_FIRST_BIT
112 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +0200113 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +0200114 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +0200115 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200116 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200117 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200118 select GENERIC_IRQ_SHOW
119 select GENERIC_PENDING_IRQ if SMP
120 select GENERIC_SMP_IDLE_THREAD
121 select GENERIC_STRNCPY_FROM_USER
122 select GENERIC_STRNLEN_USER
123 select GENERIC_TIME_VSYSCALL
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200124 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200125 select HAVE_ACPI_APEI if ACPI
126 select HAVE_ACPI_APEI_NMI if ACPI
127 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200128 select HAVE_ARCH_AUDITSYSCALL
129 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
130 select HAVE_ARCH_JUMP_LABEL
Ard Biesheuvelb34006c2018-09-18 23:51:41 -0700131 select HAVE_ARCH_JUMP_LABEL_RELATIVE
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800132 select HAVE_ARCH_KASAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200133 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800134 select HAVE_ARCH_MMAP_RND_BITS if MMU
135 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300136 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ard Biesheuvel271ca782018-08-21 21:56:00 -0700137 select HAVE_ARCH_PREL32_RELOCATIONS
Ingo Molnar6471b822015-06-03 10:00:13 +0200138 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700139 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Alexander Popovafaef012018-08-17 01:16:58 +0300140 select HAVE_ARCH_STACKLEAK
Ingo Molnar6471b822015-06-03 10:00:13 +0200141 select HAVE_ARCH_TRACEHOOK
142 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Matthew Wilcoxa00cc7d2017-02-24 14:57:02 -0800143 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
Andy Lutomirskie37e43a2016-08-11 02:35:23 -0700144 select HAVE_ARCH_VMAP_STACK if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100145 select HAVE_ARCH_WITHIN_STACK_FRAMES
Ingo Molnar6471b822015-06-03 10:00:13 +0200146 select HAVE_CMPXCHG_DOUBLE
147 select HAVE_CMPXCHG_LOCAL
148 select HAVE_CONTEXT_TRACKING if X86_64
Josh Triplettc1bd55f2015-06-30 15:00:00 -0700149 select HAVE_COPY_THREAD_TLS
Ingo Molnar6471b822015-06-03 10:00:13 +0200150 select HAVE_C_RECORDMCOUNT
151 select HAVE_DEBUG_KMEMLEAK
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700152 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400153 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900154 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Wang YanQing03f57812018-05-03 14:10:43 +0800155 select HAVE_EBPF_JIT
Johannes Berg58340a02008-07-25 01:45:33 -0700156 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Christoph Hellwig6630a8e2018-11-15 20:05:37 +0100157 select HAVE_EISA
Jiri Slaby5f56a5d2016-05-20 17:00:16 -0700158 select HAVE_EXIT_THREAD
Steven Rostedt (VMware)644e0e82017-03-23 10:33:52 -0400159 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
Ingo Molnar6471b822015-06-03 10:00:13 +0200160 select HAVE_FTRACE_MCOUNT_RECORD
Ingo Molnar6471b822015-06-03 10:00:13 +0200161 select HAVE_FUNCTION_GRAPH_TRACER
162 select HAVE_FUNCTION_TRACER
Emese Revfy6b90bd42016-05-24 00:09:38 +0200163 select HAVE_GCC_PLUGINS
K.Prasad0067f122009-06-01 23:43:57 +0530164 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200165 select HAVE_IDE
166 select HAVE_IOREMAP_PROT
167 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
168 select HAVE_IRQ_TIME_ACCOUNTING
169 select HAVE_KERNEL_BZIP2
170 select HAVE_KERNEL_GZIP
171 select HAVE_KERNEL_LZ4
172 select HAVE_KERNEL_LZMA
173 select HAVE_KERNEL_LZO
174 select HAVE_KERNEL_XZ
175 select HAVE_KPROBES
176 select HAVE_KPROBES_ON_FTRACE
Masami Hiramatsu540adea2018-01-13 02:55:03 +0900177 select HAVE_FUNCTION_ERROR_INJECTION
Ingo Molnar6471b822015-06-03 10:00:13 +0200178 select HAVE_KRETPROBES
179 select HAVE_KVM
180 select HAVE_LIVEPATCH if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200181 select HAVE_MEMBLOCK_NODE_MAP
Frederic Weisbecker01027522010-04-11 18:55:56 +0200182 select HAVE_MIXED_BREAKPOINTS_REGS
Josh Poimboeufee9f8fc2017-07-24 18:36:57 -0500183 select HAVE_MOD_ARCH_SPECIFIC
Joel Fernandes (Google)9f132f72019-01-03 15:28:41 -0800184 select HAVE_MOVE_PMD
Petr Mladek42a0bb32016-05-20 17:00:33 -0700185 select HAVE_NMI
Ingo Molnar6471b822015-06-03 10:00:13 +0200186 select HAVE_OPROFILE
187 select HAVE_OPTPROBES
188 select HAVE_PCSPKR_PLATFORM
189 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200190 select HAVE_PERF_EVENTS_NMI
Nicholas Piggin92e5aae2017-08-18 15:15:51 -0700191 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
Christoph Hellwigeb01d422018-11-15 20:05:32 +0100192 select HAVE_PCI
Jiri Olsac5e63192012-08-07 15:20:36 +0200193 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200194 select HAVE_PERF_USER_STACK_DUMP
Peter Zijlstra48a8b972018-08-22 17:30:16 +0200195 select HAVE_RCU_TABLE_FREE if PARAVIRT
Ingo Molnar6471b822015-06-03 10:00:13 +0200196 select HAVE_REGS_AND_STACK_ACCESS_API
Jiri Slaby6415b382018-05-18 08:47:13 +0200197 select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION
Masami Hiramatsu3c88ee194c2018-04-25 21:20:57 +0900198 select HAVE_FUNCTION_ARG_ACCESS_API
Masahiro Yamadad148eac2018-06-14 19:36:45 +0900199 select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
Ingo Molnarc763ea22016-11-15 10:26:39 +0100200 select HAVE_STACK_VALIDATION if X86_64
Mathieu Desnoyersd6761b82018-06-02 08:43:58 -0400201 select HAVE_RSEQ
Ingo Molnar6471b822015-06-03 10:00:13 +0200202 select HAVE_SYSCALL_TRACEPOINTS
Ingo Molnar6471b822015-06-03 10:00:13 +0200203 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300204 select HAVE_USER_RETURN_NOTIFIER
Thomas Gleixner05736e42018-05-29 17:48:27 +0200205 select HOTPLUG_SMT if SMP
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100206 select IRQ_FORCED_THREADING
Christoph Hellwig86596f02018-04-05 09:44:52 +0200207 select NEED_SG_DMA_LENGTH
Christoph Hellwig2eac9c22018-11-15 20:05:33 +0100208 select PCI_DOMAINS if PCI
Sinan Kaya625210c2019-01-21 23:19:58 +0000209 select PCI_LOCKLESS_CONFIG if PCI
Ingo Molnar6471b822015-06-03 10:00:13 +0200210 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500211 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200212 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200213 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500214 select SRCU
Ingo Molnar6471b822015-06-03 10:00:13 +0200215 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700216 select THREAD_INFO_IN_TASK
Ingo Molnar6471b822015-06-03 10:00:13 +0200217 select USER_STACKTRACE_SUPPORT
218 select VIRT_TO_BUS
Ingo Molnar6471b822015-06-03 10:00:13 +0200219 select X86_FEATURE_NAMES if PROC_FS
Balbir Singh7d8330a2008-02-10 12:46:28 +0530220
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200221config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100222 def_bool y
223 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200224
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700225config OUTPUT_FORMAT
226 string
227 default "elf32-i386" if X86_32
228 default "elf64-x86-64" if X86_64
229
Sam Ravnborg73531902008-05-25 23:03:18 +0200230config ARCH_DEFCONFIG
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200231 string
Sam Ravnborg73531902008-05-25 23:03:18 +0200232 default "arch/x86/configs/i386_defconfig" if X86_32
233 default "arch/x86/configs/x86_64_defconfig" if X86_64
Sam Ravnborgb9b39bfb2008-04-29 12:48:15 +0200234
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100235config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100236 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100237
238config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100239 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100240
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100241config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100242 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100243
Daniel Cashman9e08f572016-01-14 15:20:06 -0800244config ARCH_MMAP_RND_BITS_MIN
245 default 28 if 64BIT
246 default 8
247
248config ARCH_MMAP_RND_BITS_MAX
249 default 32 if 64BIT
250 default 16
251
252config ARCH_MMAP_RND_COMPAT_BITS_MIN
253 default 8
254
255config ARCH_MMAP_RND_COMPAT_BITS_MAX
256 default 16
257
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100258config SBUS
259 bool
260
261config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100262 def_bool y
263 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100264
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100265config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100266 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100267 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000268 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
269
270config GENERIC_BUG_RELATIVE_POINTERS
271 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100272
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100273config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100274 def_bool y
275 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100276
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100277config GENERIC_CALIBRATE_DELAY
278 def_bool y
279
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800280config ARCH_HAS_CPU_RELAX
281 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100282
Pekka Enberg1b27d052008-04-28 02:12:22 -0700283config ARCH_HAS_CACHE_LINE_SIZE
284 def_bool y
285
Dave Hansen316d0972018-04-20 15:20:28 -0700286config ARCH_HAS_FILTER_PGPROT
287 def_bool y
288
Mike Travisdd5af902008-01-30 13:33:32 +0100289config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900290 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100291
Tejun Heo08fc4582009-08-14 15:00:49 +0900292config NEED_PER_CPU_EMBED_FIRST_CHUNK
293 def_bool y
294
295config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900296 def_bool y
297
Johannes Berg801e4062007-12-08 02:12:39 +0100298config ARCH_HIBERNATION_POSSIBLE
299 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100300
Johannes Bergf4cb5702007-12-08 02:14:00 +0100301config ARCH_SUSPEND_POSSIBLE
302 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100303
Steve Cappercfe28c52013-04-29 14:29:48 +0100304config ARCH_WANT_HUGE_PMD_SHARE
305 def_bool y
306
Steve Capper53313b22013-04-30 08:03:42 +0100307config ARCH_WANT_GENERAL_HUGETLB
308 def_bool y
309
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100310config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000311 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100312
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100313config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000314 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100315
Akinobu Mita6a11f752009-03-31 15:23:17 -0700316config ARCH_SUPPORTS_DEBUG_PAGEALLOC
317 def_bool y
318
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300319config KASAN_SHADOW_OFFSET
320 hex
321 depends on KASAN
322 default 0xdffffc0000000000
323
Shane Wang69575d32009-09-01 18:25:07 -0700324config HAVE_INTEL_TXT
325 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700326 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700327
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100328config X86_32_SMP
329 def_bool y
330 depends on X86_32 && SMP
331
332config X86_64_SMP
333 def_bool y
334 depends on X86_64 && SMP
335
Tejun Heoccbeed32009-02-09 22:17:40 +0900336config X86_32_LAZY_GS
337 def_bool y
Masahiro Yamada8458f8c2018-06-14 19:36:43 +0900338 depends on X86_32 && !STACKPROTECTOR
Tejun Heoccbeed32009-02-09 22:17:40 +0900339
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530340config ARCH_SUPPORTS_UPROBES
341 def_bool y
342
Rob Herringd20642f2014-04-18 17:19:54 -0500343config FIX_EARLYCON_MEM
344 def_bool y
345
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +0300346config DYNAMIC_PHYSICAL_MASK
347 bool
348
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700349config PGTABLE_LEVELS
350 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300351 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700352 default 4 if X86_64
353 default 3 if X86_PAE
354 default 2
355
Masahiro Yamada2a61f472018-05-28 18:22:00 +0900356config CC_HAS_SANE_STACKPROTECTOR
357 bool
358 default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
359 default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
360 help
361 We have to make sure stack protector is unconditionally disabled if
362 the compiler produces broken code.
363
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100364menu "Processor type and features"
365
Randy Dunlap5ee71532012-01-16 11:57:18 -0800366config ZONE_DMA
367 bool "DMA memory allocation support" if EXPERT
368 default y
369 help
370 DMA memory allocation support allows devices with less than 32-bit
371 addressing to allocate within the first 16MB of address space.
372 Disable if no such devices will be used.
373
374 If unsure, say Y.
375
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100376config SMP
377 bool "Symmetric multi-processing support"
378 ---help---
379 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800380 a system with only one CPU, say N. If you have a system with more
381 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100382
Robert Graffham4a474152014-01-23 15:55:29 -0800383 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100384 machines, but will use only one CPU of a multiprocessor machine. If
385 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800386 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100387 will run faster if you say N here.
388
389 Note that if you say Y here and choose architecture "586" or
390 "Pentium" under "Processor family", the kernel will not work on 486
391 architectures. Similarly, multiprocessor kernels for the "PPro"
392 architecture may not work on all Pentium based boards.
393
394 People using multiprocessor machines who say Y here should also say
395 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
396 Management" code will be disabled if you say Y here.
397
Paul Bolle395cf962011-08-15 02:02:26 +0200398 See also <file:Documentation/x86/i386/IO-APIC.txt>,
Benjamin Petersonc9525a32017-05-20 17:20:16 -0700399 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100400 <http://www.tldp.org/docs.html#howto>.
401
402 If you don't know what to do here, say N.
403
Josh Triplett9def39be2013-10-30 08:09:45 -0700404config X86_FEATURE_NAMES
405 bool "Processor feature human-readable names" if EMBEDDED
406 default y
407 ---help---
408 This option compiles in a table of x86 feature bits and corresponding
409 names. This is required to support /proc/cpuinfo and a few kernel
410 messages. You can disable this to save space, at the expense of
411 making those few kernel messages show numeric feature bits instead.
412
413 If in doubt, say Y.
414
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800415config X86_X2APIC
416 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200417 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800418 ---help---
419 This enables x2apic support on CPUs that have this feature.
420
421 This allows 32-bit apic IDs (so it can support very large systems),
422 and accesses the local apic via MSRs not via mmio.
423
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800424 If you don't know what to do here, say N.
425
Yinghai Lu6695c852008-06-19 12:13:09 -0700426config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700427 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000428 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200429 depends on X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100430 ---help---
Yinghai Lu6695c852008-06-19 12:13:09 -0700431 For old smp systems that do not have proper acpi support. Newer systems
432 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700433
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000434config GOLDFISH
435 def_bool y
436 depends on X86_GOLDFISH
437
David Woodhouse76b04382018-01-11 21:46:25 +0000438config RETPOLINE
439 bool "Avoid speculative indirect branches in kernel"
440 default y
Peter Zijlstrad5028ba2018-02-06 09:46:13 +0100441 select STACK_VALIDATION if HAVE_STACK_VALIDATION
David Woodhouse76b04382018-01-11 21:46:25 +0000442 help
443 Compile kernel with the retpoline compiler options to guard against
444 kernel-to-user data leaks by avoiding speculative indirect
445 branches. Requires a compiler with -mindirect-branch=thunk-extern
446 support for full protection. The kernel may run slower.
447
Johannes Weinere6d42932019-01-29 17:44:36 -0500448config X86_CPU_RESCTRL
449 bool "x86 CPU resource control support"
Babu Moger6fe07ce2018-11-21 20:28:39 +0000450 depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100451 select KERNFS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700452 help
Johannes Weinere6d42932019-01-29 17:44:36 -0500453 Enable x86 CPU resource control support.
Babu Moger6fe07ce2018-11-21 20:28:39 +0000454
455 Provide support for the allocation and monitoring of system resources
456 usage by the CPU.
457
458 Intel calls this Intel Resource Director Technology
459 (Intel(R) RDT). More information about RDT can be found in the
460 Intel x86 Architecture Software Developer Manual.
461
462 AMD calls this AMD Platform Quality of Service (AMD QoS).
463 More information about AMD QoS can be found in the AMD64 Technology
464 Platform Quality of Service Extensions manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700465
466 Say N if unsure.
467
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800468if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800469config X86_BIGSMP
470 bool "Support for big SMP systems with more than 8 CPUs"
471 depends on SMP
472 ---help---
473 This option is needed for the systems that have more than 8 CPUs
474
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800475config X86_EXTENDED_PLATFORM
476 bool "Support for extended (non-PC) x86 platforms"
477 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100478 ---help---
Ingo Molnar06ac8342009-01-27 18:11:43 +0100479 If you disable this option then the kernel will only support
480 standard PC platforms. (which covers the vast majority of
481 systems out there.)
482
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800483 If you enable this option then you'll be able to select support
484 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100485 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800486 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800487 RDC R-321x SoC
488 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200489 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200490 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100491
492 If you have one of these systems, or if you want to build a
493 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800494endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100495
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800496if X86_64
497config X86_EXTENDED_PLATFORM
498 bool "Support for extended (non-PC) x86 platforms"
499 default y
500 ---help---
501 If you disable this option then the kernel will only support
502 standard PC platforms. (which covers the vast majority of
503 systems out there.)
504
505 If you enable this option then you'll be able to select support
506 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800507 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800508 ScaleMP vSMP
509 SGI Ultraviolet
510
511 If you have one of these systems, or if you want to build a
512 generic distribution kernel, say Y here - otherwise say N.
513endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800514# This is an alphabetically sorted list of 64 bit extended platforms
515# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800516config X86_NUMACHIP
517 bool "Numascale NumaChip"
518 depends on X86_64
519 depends on X86_EXTENDED_PLATFORM
520 depends on NUMA
521 depends on SMP
522 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700523 depends on PCI_MMCONFIG
Steffen Persvold44b111b52011-12-06 00:07:26 +0800524 ---help---
525 Adds support for Numascale NumaChip large-SMP systems. Needed to
526 enable more than ~168 cores.
527 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100528
Ingo Molnar6a485652009-01-27 18:29:13 +0100529config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800530 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100531 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100532 select PARAVIRT
533 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800534 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300535 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100536 ---help---
Ingo Molnar6a485652009-01-27 18:29:13 +0100537 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
538 supposed to run on these EM64T-based machines. Only choose this option
539 if you have one of these machines.
540
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800541config X86_UV
542 bool "SGI Ultraviolet"
543 depends on X86_64
544 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500545 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800546 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700547 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200548 depends on PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800549 ---help---
550 This option is needed in order to support SGI Ultraviolet systems.
551 If you don't have one of these, you should say N here.
552
553# Following is an alphabetically sorted list of 32 bit extended platforms
554# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100555
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000556config X86_GOLDFISH
557 bool "Goldfish (Virtual Platform)"
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100558 depends on X86_EXTENDED_PLATFORM
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000559 ---help---
560 Enable support for the Goldfish virtual platform used primarily
561 for Android development. Unless you are building for the Android
562 Goldfish emulator say N here.
563
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800564config X86_INTEL_CE
565 bool "CE4100 TV platform"
566 depends on PCI
567 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800568 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800569 depends on X86_32
570 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800571 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100572 select OF
573 select OF_EARLY_FLATTREE
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800574 ---help---
575 Select for the Intel CE media processor (CE4100) SOC.
576 This option compiles in support for the CE4100 SOC for settop
577 boxes and media devices.
578
David Cohen4cb9b002013-12-16 17:37:26 -0800579config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100580 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100581 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800582 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000583 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200584 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000585 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000586 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800587 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000588 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000589 select APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000590 select INTEL_SCU_IPC
Mika Westerberg15a713d2012-01-26 17:35:05 +0000591 select MFD_INTEL_MSIC
Alan Cox1ea7c672011-11-10 13:29:14 +0000592 ---help---
David Cohen4cb9b002013-12-16 17:37:26 -0800593 Select to build a kernel capable of supporting Intel MID (Mobile
594 Internet Device) platform systems which do not have the PCI legacy
595 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000596
David Cohen4cb9b002013-12-16 17:37:26 -0800597 Intel MID platforms are based on an Intel processor and chipset which
598 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100599
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000600config X86_INTEL_QUARK
601 bool "Intel Quark platform support"
602 depends on X86_32
603 depends on X86_EXTENDED_PLATFORM
604 depends on X86_PLATFORM_DEVICES
605 depends on X86_TSC
606 depends on PCI
607 depends on PCI_GOANY
608 depends on X86_IO_APIC
609 select IOSF_MBI
610 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200611 select COMMON_CLK
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000612 ---help---
613 Select to include support for Quark X1000 SoC.
614 Say Y here if you have a Quark based system such as the Arduino
615 compatible Intel Galileo.
616
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000617config X86_INTEL_LPSS
618 bool "Intel Low Power Subsystem Support"
Sinan Kaya5962dd22019-01-02 18:10:37 +0000619 depends on X86 && ACPI && PCI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000620 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300621 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100622 select IOSF_MBI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000623 ---help---
624 Select to build support for Intel Low Power Subsystem such as
625 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300626 things like clock tree (common clock framework) and pincontrol
627 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000628
Ken Xue92082a82015-02-06 08:27:51 +0800629config X86_AMD_PLATFORM_DEVICE
630 bool "AMD ACPI2Platform devices support"
631 depends on ACPI
632 select COMMON_CLK
633 select PINCTRL
634 ---help---
635 Select to interpret AMD specific ACPI device to platform device
636 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
637 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
638 implemented under PINCTRL subsystem.
639
David E. Boxced3ce72014-09-17 22:13:50 -0700640config IOSF_MBI
641 tristate "Intel SoC IOSF Sideband support for SoC platforms"
642 depends on PCI
643 ---help---
644 This option enables sideband register access support for Intel SoC
645 platforms. On these platforms the IOSF sideband is used in lieu of
646 MSR's for some register accesses, mostly but not limited to thermal
647 and power. Drivers may query the availability of this device to
648 determine if they need the sideband in order to work on these
649 platforms. The sideband is available on the following SoC products.
650 This list is not meant to be exclusive.
651 - BayTrail
652 - Braswell
653 - Quark
654
655 You should say Y if you are running a kernel on one of these SoC's.
656
David E. Boxed2226b2014-09-17 22:13:51 -0700657config IOSF_MBI_DEBUG
658 bool "Enable IOSF sideband access through debugfs"
659 depends on IOSF_MBI && DEBUG_FS
660 ---help---
661 Select this option to expose the IOSF sideband access registers (MCR,
662 MDR, MCRX) through debugfs to write and read register information from
663 different units on the SoC. This is most useful for obtaining device
664 state information for debug and analysis. As this is a general access
665 mechanism, users of this option would have specific knowledge of the
666 device they want to access.
667
668 If you don't require the option or are in doubt, say N.
669
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800670config X86_RDC321X
671 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100672 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800673 depends on X86_EXTENDED_PLATFORM
674 select M486
675 select X86_REBOOTFIXUPS
676 ---help---
677 This option is needed for RDC R-321x system-on-chip, also known
678 as R-8610-(G).
679 If you don't have one of these chips, you should say N here.
680
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100681config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100682 bool "Support non-standard 32-bit SMP architectures"
683 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800684 depends on X86_EXTENDED_PLATFORM
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100685 ---help---
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800686 This option compiles in the bigsmp and STA2X11 default
687 subarchitectures. It is intended for a generic binary
688 kernel. If you select them all, kernel will probe it one by
689 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700690
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800691# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700692
Linus Torvaldsd949f362009-09-26 09:35:07 -0700693config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100694 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700695 # MCE code calls memory_failure():
696 depends on X86_MCE
697 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700698 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
699 depends on X86_64 || !SPARSEMEM
700 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700701
Alessandro Rubini83125a32012-04-04 19:40:21 +0200702config STA2X11
703 bool "STA2X11 Companion Chip Support"
704 depends on X86_32_NON_STANDARD && PCI
Christoph Hellwigb6e05472018-03-19 11:38:24 +0100705 select ARCH_HAS_PHYS_TO_DMA
Alessandro Rubini83125a32012-04-04 19:40:21 +0200706 select SWIOTLB
707 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200708 select GPIOLIB
Alessandro Rubini83125a32012-04-04 19:40:21 +0200709 ---help---
710 This adds support for boards based on the STA2X11 IO-Hub,
711 a.k.a. "ConneXt". The chip is used in place of the standard
712 PC chipset, so all "standard" peripherals are missing. If this
713 option is selected the kernel will still be able to boot on
714 standard PC machines.
715
Shérab82148d12010-09-25 06:06:57 +0200716config X86_32_IRIS
717 tristate "Eurobraille/Iris poweroff module"
718 depends on X86_32
719 ---help---
720 The Iris machines from EuroBraille do not have APM or ACPI support
721 to shut themselves down properly. A special I/O sequence is
722 needed to do so, which is what this module does at
723 kernel shutdown.
724
725 This is only for Iris machines from EuroBraille.
726
727 If unused, say N.
728
Ingo Molnarae1e9132008-11-11 09:05:16 +0100729config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100730 def_bool y
731 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800732 depends on X86
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100733 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100734 Calculate simpler /proc/<PID>/wchan values. If this option
735 is disabled then wchan values will recurse back to the
736 caller function. This provides more accurate wchan values,
737 at the expense of slightly more scheduling overhead.
738
739 If in doubt, say "Y".
740
Borislav Petkov6276a072013-03-04 21:20:21 +0100741menuconfig HYPERVISOR_GUEST
742 bool "Linux guest support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100743 ---help---
Borislav Petkov6276a072013-03-04 21:20:21 +0100744 Say Y here to enable options for running Linux under various hyper-
745 visors. This option enables basic hypervisor detection and platform
746 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100747
Borislav Petkov6276a072013-03-04 21:20:21 +0100748 If you say N, all options in this submenu will be skipped and
749 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100750
Borislav Petkov6276a072013-03-04 21:20:21 +0100751if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100752
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100753config PARAVIRT
754 bool "Enable paravirtualization code"
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100755 ---help---
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100756 This changes the kernel so it can modify itself when it is run
757 under a hypervisor, potentially improving performance significantly
758 over full virtualization. However, when run without a hypervisor
759 the kernel is theoretically slower and slightly larger.
760
Juergen Grossc00a2802018-08-28 09:40:21 +0200761config PARAVIRT_XXL
762 bool
763
Borislav Petkov6276a072013-03-04 21:20:21 +0100764config PARAVIRT_DEBUG
765 bool "paravirt-ops debugging"
766 depends on PARAVIRT && DEBUG_KERNEL
767 ---help---
768 Enable to debug paravirt_ops internals. Specifically, BUG if
769 a paravirt_op is missing when it is called.
770
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700771config PARAVIRT_SPINLOCKS
772 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700773 depends on PARAVIRT && SMP
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700774 ---help---
775 Paravirtualized spinlocks allow a pvops backend to replace the
776 spinlock implementation with something virtualization-friendly
777 (for example, block the virtual CPU rather than spinning).
778
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530779 It has a minimal impact on native kernels and gives a nice performance
780 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700781
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530782 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700783
Borislav Petkov6276a072013-03-04 21:20:21 +0100784source "arch/x86/xen/Kconfig"
785
786config KVM_GUEST
787 bool "KVM Guest support (including kvmclock)"
788 depends on PARAVIRT
789 select PARAVIRT_CLOCK
790 default y
791 ---help---
792 This option enables various optimizations for running under the KVM
793 hypervisor. It includes a paravirtualized clock, so that instead
794 of relying on a PIT (or probably other) emulation by the
795 underlying device model, the host provides the guest with
796 timing infrastructure such as time of day, and system time
797
Maran Wilson77336072018-12-10 11:07:28 -0800798config PVH
799 bool "Support for running PVH guests"
800 ---help---
801 This option enables the PVH entry point for guest virtual machines
802 as specified in the x86/HVM direct boot ABI.
803
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530804config KVM_DEBUG_FS
805 bool "Enable debug information for KVM Guests in debugfs"
806 depends on KVM_GUEST && DEBUG_FS
Srivatsa Vaddagiri1e20eb82013-08-09 19:52:01 +0530807 ---help---
808 This option enables collection of various statistics for KVM guest.
809 Statistics are displayed in debugfs filesystem. Enabling this option
810 may incur significant overhead.
811
Borislav Petkov6276a072013-03-04 21:20:21 +0100812config PARAVIRT_TIME_ACCOUNTING
813 bool "Paravirtual steal time accounting"
814 depends on PARAVIRT
Borislav Petkov6276a072013-03-04 21:20:21 +0100815 ---help---
816 Select this option to enable fine granularity task steal time
817 accounting. Time spent executing other tasks in parallel with
818 the current vCPU is discounted from the vCPU power. To account for
819 that, there can be a small performance impact.
820
821 If in doubt, say N here.
822
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200823config PARAVIRT_CLOCK
824 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200825
Jan Kiszka4a362602017-11-27 09:11:46 +0100826config JAILHOUSE_GUEST
827 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100828 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100829 select X86_PM_TIMER
Jan Kiszka4a362602017-11-27 09:11:46 +0100830 ---help---
831 This option allows to run Linux as guest in a Jailhouse non-root
832 cell. You can leave this option disabled if you only want to start
833 Jailhouse and run Linux afterwards in the root cell.
834
Borislav Petkov6276a072013-03-04 21:20:21 +0100835endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400836
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100837source "arch/x86/Kconfig.cpu"
838
839config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100840 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100841 prompt "HPET Timer Support" if X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100842 ---help---
843 Use the IA-PC HPET (High Precision Event Timer) to manage
844 time in preference to the PIT and RTC, if a HPET is
845 present.
846 HPET is the next generation timer replacing legacy 8254s.
847 The HPET provides a stable time base on SMP
848 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200849 as it is off-chip. The interface used is documented
850 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100851
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100852 You can safely choose Y here. However, HPET will only be
853 activated if the platform and the BIOS support this feature.
854 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100855
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100856 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100857
858config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100859 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800860 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100861
Jacob Panbb24c472009-09-02 07:37:17 -0700862config APB_TIMER
Alan Cox933b9462011-12-17 17:43:40 +0000863 def_bool y if X86_INTEL_MID
864 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
Jamie Iles06c3df42011-06-06 12:43:07 +0100865 select DW_APB_TIMER
Alan Coxa0c38322011-12-17 21:57:25 +0000866 depends on X86_INTEL_MID && SFI
Jacob Panbb24c472009-09-02 07:37:17 -0700867 help
868 APB timer is the replacement for 8254, HPET on X86 MID platforms.
869 The APBT provides a stable time base on SMP
870 systems, unlike the TSC, but it is more expensive to access,
871 as it is off-chip. APB timers are always running regardless of CPU
872 C states, they are used as per CPU clockevent device when possible.
873
David Rientjes6a108a12011-01-20 14:44:16 -0800874# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100875# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700876config DMI
877 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800878 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800879 bool "Enable DMI scanning" if EXPERT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100880 ---help---
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700881 Enabled scanning of DMI to identify machine quirks. Say Y
882 here unless you have verified that your setup is not
883 affected by entries in the DMI blacklist. Required by PNP
884 BIOS code.
885
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100886config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700887 bool "Old AMD GART IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200888 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100889 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200890 depends on X86_64 && PCI && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100891 ---help---
Ingo Molnarced3c422013-10-06 11:45:20 +0200892 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
893 GART based hardware IOMMUs.
894
895 The GART supports full DMA access for devices with 32-bit access
896 limitations, on systems with more than 3 GB. This is usually needed
897 for USB, sound, many IDE/SATA chipsets and some other devices.
898
899 Newer systems typically have a modern AMD IOMMU, supported via
900 the CONFIG_AMD_IOMMU=y config option.
901
902 In normal configurations this driver is only active when needed:
903 there's more than 3 GB of memory and the system contains a
904 32-bit limited device.
905
906 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100907
908config CALGARY_IOMMU
909 bool "IBM Calgary IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200910 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100911 select SWIOTLB
Kees Cook6ea30382012-10-02 11:16:47 -0700912 depends on X86_64 && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100913 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100914 Support for hardware IOMMUs in IBM's xSeries x366 and x460
915 systems. Needed to run systems with more than 3GB of memory
916 properly with 32-bit PCI devices that do not support DAC
917 (Double Address Cycle). Calgary also supports bus level
918 isolation, where all DMAs pass through the IOMMU. This
919 prevents them from going anywhere except their intended
920 destination. This catches hard-to-find kernel bugs and
921 mis-behaving drivers and devices that do not use the DMA-API
922 properly to set up their DMA buffers. The IOMMU can be
923 turned off at boot time with the iommu=off parameter.
924 Normally the kernel will make the right choice by itself.
925 If unsure, say Y.
926
927config CALGARY_IOMMU_ENABLED_BY_DEFAULT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100928 def_bool y
929 prompt "Should Calgary be enabled by default?"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100930 depends on CALGARY_IOMMU
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100931 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100932 Should Calgary be enabled by default? if you choose 'y', Calgary
933 will be used (if it exists). If you choose 'n', Calgary will not be
934 used even if it exists. If you choose 'n' and would like to use
935 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
936 If unsure, say Y.
937
Mike Travis1184dc22008-05-12 21:21:12 +0200938config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200939 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700940 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800941 select CPUMASK_OFFSTACK
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100942 ---help---
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200943 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200944 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100945
Ingo Molnaraec64872018-02-10 12:36:29 +0100946#
947# The maximum number of CPUs supported:
948#
949# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
950# and which can be configured interactively in the
951# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
952#
953# The ranges are different on 32-bit and 64-bit kernels, depending on
954# hardware capabilities and scalability features of the kernel.
955#
956# ( If MAXSMP is enabled we just use the highest possible value and disable
957# interactive configuration. )
958#
959
960config NR_CPUS_RANGE_BEGIN
961 int
962 default NR_CPUS_RANGE_END if MAXSMP
963 default 1 if !SMP
964 default 2
965
966config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800967 int
968 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100969 default 64 if SMP && X86_BIGSMP
970 default 8 if SMP && !X86_BIGSMP
971 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800972
Ingo Molnaraec64872018-02-10 12:36:29 +0100973config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800974 int
975 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100976 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
977 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
978 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800979
Ingo Molnaraec64872018-02-10 12:36:29 +0100980config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800981 int
982 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100983 default 32 if X86_BIGSMP
984 default 8 if SMP
985 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800986
Ingo Molnaraec64872018-02-10 12:36:29 +0100987config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800988 int
989 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100990 default 8192 if MAXSMP
991 default 64 if SMP
992 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800993
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100994config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800995 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +0100996 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
997 default NR_CPUS_DEFAULT
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100998 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100999 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -05001000 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +03001001 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001002 minimum value which makes sense is 2.
1003
Ingo Molnaraec64872018-02-10 12:36:29 +01001004 This is purely to save memory: each supported CPU adds about 8KB
1005 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001006
1007config SCHED_SMT
Thomas Gleixnerdbe73362018-11-25 19:33:37 +01001008 def_bool y if SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001009
1010config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001011 def_bool y
1012 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001013 depends on SMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001014 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001015 Multi-core scheduler support improves the CPU scheduler's decision
1016 making when dealing with multi-core CPU chips at a cost of slightly
1017 increased overhead in some places. If unsure say N here.
1018
Tim Chende966cf2016-11-29 10:43:27 -08001019config SCHED_MC_PRIO
1020 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001021 depends on SCHED_MC && CPU_SUP_INTEL
1022 select X86_INTEL_PSTATE
1023 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001024 default y
Tim Chen5e76b2a2016-11-22 12:23:55 -08001025 ---help---
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001026 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1027 core ordering determined at manufacturing time, which allows
1028 certain cores to reach higher turbo frequencies (when running
1029 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001030
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001031 Enabling this kernel feature teaches the scheduler about
1032 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1033 scheduler's CPU selection logic accordingly, so that higher
1034 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001035
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001036 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001037
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001038 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001039
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001040config UP_LATE_INIT
1041 def_bool y
Thomas Gleixnerba360f8872015-01-24 10:34:46 +01001042 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001043
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001044config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001045 bool "Local APIC support on uniprocessors" if !PCI_MSI
1046 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001047 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001048 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001049 A local APIC (Advanced Programmable Interrupt Controller) is an
1050 integrated interrupt controller in the CPU. If you have a single-CPU
1051 system which has a processor with a local APIC, you can say Y here to
1052 enable and use it. If you say Y here even though your machine doesn't
1053 have a local APIC, then the kernel will still run with no slowdown at
1054 all. The local APIC supports CPU-generated self-interrupts (timer,
1055 performance counters), and the NMI watchdog which detects hard
1056 lockups.
1057
1058config X86_UP_IOAPIC
1059 bool "IO-APIC support on uniprocessors"
1060 depends on X86_UP_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001061 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001062 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1063 SMP-capable replacement for PC-style interrupt controllers. Most
1064 SMP systems and many recent uniprocessor systems have one.
1065
1066 If you have a single-CPU system with an IO-APIC, you can say Y here
1067 to use it. If you say Y here even though your machine doesn't have
1068 an IO-APIC, then the kernel will still run with no slowdown at all.
1069
1070config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001071 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001072 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001073 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001074 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001075
1076config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001077 def_bool y
1078 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001079
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001080config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1081 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001082 depends on X86_IO_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001083 ---help---
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001084 This option enables a workaround that fixes a source of
1085 spurious interrupts. This is recommended when threaded
1086 interrupt handling is used on systems where the generation of
1087 superfluous "boot interrupts" cannot be disabled.
1088
1089 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1090 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1091 kernel does during interrupt handling). On chipsets where this
1092 boot IRQ generation cannot be disabled, this workaround keeps
1093 the original IRQ line masked so that only the equivalent "boot
1094 IRQ" is delivered to the CPUs. The workaround also tells the
1095 kernel to set up the IRQ handler on the boot IRQ line. In this
1096 way only one interrupt is delivered to the kernel. Otherwise
1097 the spurious second interrupt may cause the kernel to bring
1098 down (vital) interrupt lines.
1099
1100 Only affects "broken" chipsets. Interrupt sharing may be
1101 increased on these systems.
1102
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001103config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001104 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001105 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001106 default y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001107 ---help---
Andi Kleenbab9bc62009-07-09 00:31:38 +02001108 Machine Check support allows the processor to notify the
1109 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001110 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001111 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001112
Tony Luck5de97c92017-03-27 11:33:03 +02001113config X86_MCELOG_LEGACY
1114 bool "Support for deprecated /dev/mcelog character device"
1115 depends on X86_MCE
1116 ---help---
1117 Enable support for /dev/mcelog which is needed by the old mcelog
1118 userspace logging daemon. Consider switching to the new generation
1119 rasdaemon solution.
1120
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001121config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001122 def_bool y
1123 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001124 depends on X86_MCE && X86_LOCAL_APIC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001125 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001126 Additional support for intel specific MCE features such as
1127 the thermal monitor.
1128
1129config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001130 def_bool y
1131 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001132 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001133 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001134 Additional support for AMD specific MCE features such as
1135 the DRAM Error Threshold.
1136
Andi Kleen4efc0672009-04-28 19:07:31 +02001137config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001138 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001139 depends on X86_32 && X86_MCE
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001140 ---help---
1141 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001142 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001143 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001144
Andi Kleenb2762682009-02-12 13:49:31 +01001145config X86_MCE_THRESHOLD
1146 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001147 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001148
Andi Kleenea149b32009-04-29 19:31:00 +02001149config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001150 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001151 tristate "Machine check injector support"
1152 ---help---
1153 Provide support for injecting machine checks for testing purposes.
1154 If you don't know what a machine check is and you don't do kernel
1155 QA it is safe to say n.
1156
Andi Kleen4efc0672009-04-28 19:07:31 +02001157config X86_THERMAL_VECTOR
1158 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001159 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001160
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001161source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001162
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001163config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001164 bool "Legacy VM86 support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001165 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001166 ---help---
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001167 This option allows user programs to put the CPU into V8086
1168 mode, which is an 80286-era approximation of 16-bit real mode.
1169
1170 Some very old versions of X and/or vbetool require this option
1171 for user mode setting. Similarly, DOSEMU will use it if
1172 available to accelerate real mode DOS programs. However, any
1173 recent version of DOSEMU, X, or vbetool should be fully
1174 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001175 fall back to software emulation. Nevertheless, if you are using
1176 a 16-bit DOS program where 16-bit performance matters, vm86
1177 mode might be faster than emulation and you might want to
1178 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001179
Ingo Molnar1e642812015-09-05 08:58:10 +02001180 Note that any app that works on a 64-bit kernel is unlikely to
1181 need this option, as 64-bit kernels don't, and can't, support
1182 V8086 mode. This option is also unrelated to 16-bit protected
1183 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001184
Ingo Molnar1e642812015-09-05 08:58:10 +02001185 Enabling this option increases the complexity of the kernel
1186 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001187
Ingo Molnar1e642812015-09-05 08:58:10 +02001188 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001189
1190config VM86
1191 bool
1192 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001193
1194config X86_16BIT
1195 bool "Enable support for 16-bit segments" if EXPERT
1196 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001197 depends on MODIFY_LDT_SYSCALL
H. Peter Anvin34273f42014-05-04 10:36:22 -07001198 ---help---
1199 This option is required by programs like Wine to run 16-bit
1200 protected mode legacy code on x86 processors. Disabling
1201 this option saves about 300 bytes on i386, or around 6K text
1202 plus 16K runtime memory on x86-64,
1203
1204config X86_ESPFIX32
1205 def_bool y
1206 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001207
H. Peter Anvin197725d2014-05-04 10:00:49 -07001208config X86_ESPFIX64
1209 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001210 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001211
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001212config X86_VSYSCALL_EMULATION
1213 bool "Enable vsyscall emulation" if EXPERT
1214 default y
1215 depends on X86_64
1216 ---help---
1217 This enables emulation of the legacy vsyscall page. Disabling
1218 it is roughly equivalent to booting with vsyscall=none, except
1219 that it will also disable the helpful warning if a program
1220 tries to use a vsyscall. With this option set to N, offending
1221 programs will just segfault, citing addresses of the form
1222 0xffffffffff600?00.
1223
1224 This option is required by many programs built before 2013, and
1225 care should be used even with newer programs if set to N.
1226
1227 Disabling this option saves about 7K of kernel size and
1228 possibly 4K of additional runtime pagetable memory.
1229
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001230config TOSHIBA
1231 tristate "Toshiba Laptop support"
1232 depends on X86_32
1233 ---help---
1234 This adds a driver to safely access the System Management Mode of
1235 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1236 not work on models with a Phoenix BIOS. The System Management Mode
1237 is used to set the BIOS and power saving options on Toshiba portables.
1238
1239 For information on utilities to make use of this driver see the
1240 Toshiba Linux utilities web site at:
1241 <http://www.buzzard.org.uk/toshiba/>.
1242
1243 Say Y if you intend to run this kernel on a Toshiba portable.
1244 Say N otherwise.
1245
1246config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001247 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001248 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001249 select SENSORS_DELL_SMM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001250 ---help---
Pali Rohár039ae582015-05-14 13:16:37 +02001251 This option enables legacy /proc/i8k userspace interface in hwmon
1252 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1253 temperature and allows controlling fan speeds of Dell laptops via
1254 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1255 it reports also power and hotkey status. For fan speed control is
1256 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001257
Pali Rohár039ae582015-05-14 13:16:37 +02001258 Say Y if you intend to run this kernel on old Dell laptops or want to
1259 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001260 Say N otherwise.
1261
1262config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001263 bool "Enable X86 board specific fixups for reboot"
1264 depends on X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001265 ---help---
1266 This enables chipset and/or board specific fixups to be done
1267 in order to get reboot to work correctly. This is only needed on
1268 some combinations of hardware and BIOS. The symptom, for which
1269 this config is intended, is when reboot ends with a stalled/hung
1270 system.
1271
1272 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001273 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001274
1275 Say Y if you want to enable the fixup. Currently, it's safe to
1276 enable this option even if you don't need it.
1277 Say N otherwise.
1278
1279config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001280 bool "CPU microcode loading support"
1281 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001282 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001283 select FW_LOADER
1284 ---help---
1285 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001286 Intel and AMD processors. The Intel support is for the IA32 family,
1287 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1288 AMD support is for families 0x10 and later. You will obviously need
1289 the actual microcode binary data itself which is not shipped with
1290 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001291
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001292 The preferred method to load microcode from a detached initrd is described
Jaak Ristioja1897a962018-02-09 11:22:16 +02001293 in Documentation/x86/microcode.txt. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001294 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1295 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001296
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001297 In addition, you can build the microcode into the kernel. For that you
1298 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1299 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001300
Peter Oruba8d86f392008-07-28 18:44:21 +02001301config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001302 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001303 depends on MICROCODE
1304 default MICROCODE
1305 select FW_LOADER
1306 ---help---
1307 This options enables microcode patch loading support for Intel
1308 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001309
Alanb8989db2014-01-20 18:01:56 +00001310 For the current Intel microcode data package go to
1311 <https://downloadcenter.intel.com> and search for
1312 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001313
Peter Oruba80cc9f12008-07-28 18:44:22 +02001314config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001315 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001316 depends on MICROCODE
1317 select FW_LOADER
1318 ---help---
1319 If you select this option, microcode patch loading support for AMD
1320 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001321
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001322config MICROCODE_OLD_INTERFACE
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001323 bool "Ancient loading interface (DEPRECATED)"
1324 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001325 depends on MICROCODE
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001326 ---help---
1327 DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface
1328 which was used by userspace tools like iucode_tool and microcode.ctl.
1329 It is inadequate because it runs too late to be able to properly
1330 load microcode on a machine and it needs special tools. Instead, you
1331 should've switched to the early loading method with the initrd or
1332 builtin microcode by now: Documentation/x86/microcode.txt
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001333
1334config X86_MSR
1335 tristate "/dev/cpu/*/msr - Model-specific register support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001336 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001337 This device gives privileged processes access to the x86
1338 Model-Specific Registers (MSRs). It is a character device with
1339 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1340 MSR accesses are directed to a specific CPU on multi-processor
1341 systems.
1342
1343config X86_CPUID
1344 tristate "/dev/cpu/*/cpuid - CPU information support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001345 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001346 This device gives processes access to the x86 CPUID instruction to
1347 be executed on a specific processor. It is a character device
1348 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1349 /dev/cpu/31/cpuid.
1350
1351choice
1352 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001353 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001354 depends on X86_32
1355
1356config NOHIGHMEM
1357 bool "off"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001358 ---help---
1359 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1360 However, the address space of 32-bit x86 processors is only 4
1361 Gigabytes large. That means that, if you have a large amount of
1362 physical memory, not all of it can be "permanently mapped" by the
1363 kernel. The physical memory that's not permanently mapped is called
1364 "high memory".
1365
1366 If you are compiling a kernel which will never run on a machine with
1367 more than 1 Gigabyte total physical RAM, answer "off" here (default
1368 choice and suitable for most users). This will result in a "3GB/1GB"
1369 split: 3GB are mapped so that each process sees a 3GB virtual memory
1370 space and the remaining part of the 4GB virtual memory space is used
1371 by the kernel to permanently map as much physical memory as
1372 possible.
1373
1374 If the machine has between 1 and 4 Gigabytes physical RAM, then
1375 answer "4GB" here.
1376
1377 If more than 4 Gigabytes is used then answer "64GB" here. This
1378 selection turns Intel PAE (Physical Address Extension) mode on.
1379 PAE implements 3-level paging on IA32 processors. PAE is fully
1380 supported by Linux, PAE mode is implemented on all recent Intel
1381 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1382 then the kernel will not boot on CPUs that don't support PAE!
1383
1384 The actual amount of total physical memory will either be
1385 auto detected or can be forced by using a kernel command line option
1386 such as "mem=256M". (Try "man bootparam" or see the documentation of
1387 your boot loader (lilo or loadlin) about how to pass options to the
1388 kernel at boot time.)
1389
1390 If unsure, say "off".
1391
1392config HIGHMEM4G
1393 bool "4GB"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001394 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001395 Select this if you have a 32-bit processor and between 1 and 4
1396 gigabytes of physical RAM.
1397
1398config HIGHMEM64G
1399 bool "64GB"
Matthew Whitehead69b8d3f2018-02-15 11:54:55 -05001400 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001401 select X86_PAE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001402 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001403 Select this if you have a 32-bit processor and more than 4
1404 gigabytes of physical RAM.
1405
1406endchoice
1407
1408choice
David Rientjes6a108a12011-01-20 14:44:16 -08001409 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001410 default VMSPLIT_3G
1411 depends on X86_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001412 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001413 Select the desired split between kernel and user memory.
1414
1415 If the address range available to the kernel is less than the
1416 physical memory installed, the remaining memory will be available
1417 as "high memory". Accessing high memory is a little more costly
1418 than low memory, as it needs to be mapped into the kernel first.
1419 Note that increasing the kernel address space limits the range
1420 available to user programs, making the address space there
1421 tighter. Selecting anything other than the default 3G/1G split
1422 will also likely make your kernel incompatible with binary-only
1423 kernel modules.
1424
1425 If you are not absolutely sure what you are doing, leave this
1426 option alone!
1427
1428 config VMSPLIT_3G
1429 bool "3G/1G user/kernel split"
1430 config VMSPLIT_3G_OPT
1431 depends on !X86_PAE
1432 bool "3G/1G user/kernel split (for full 1G low memory)"
1433 config VMSPLIT_2G
1434 bool "2G/2G user/kernel split"
1435 config VMSPLIT_2G_OPT
1436 depends on !X86_PAE
1437 bool "2G/2G user/kernel split (for full 2G low memory)"
1438 config VMSPLIT_1G
1439 bool "1G/3G user/kernel split"
1440endchoice
1441
1442config PAGE_OFFSET
1443 hex
1444 default 0xB0000000 if VMSPLIT_3G_OPT
1445 default 0x80000000 if VMSPLIT_2G
1446 default 0x78000000 if VMSPLIT_2G_OPT
1447 default 0x40000000 if VMSPLIT_1G
1448 default 0xC0000000
1449 depends on X86_32
1450
1451config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001452 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001453 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001454
1455config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001456 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001457 depends on X86_32 && !HIGHMEM4G
Christoph Hellwigd4a451d2018-04-03 16:24:20 +02001458 select PHYS_ADDR_T_64BIT
Christian Melki9d99c712015-10-05 17:31:33 +02001459 select SWIOTLB
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001460 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001461 PAE is required for NX support, and furthermore enables
1462 larger swapspace support for non-overcommit purposes. It
1463 has the cost of more pagetable lookup overhead, and also
1464 consumes more pagetable space per process.
1465
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001466config X86_5LEVEL
1467 bool "Enable 5-level page tables support"
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001468 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001469 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001470 depends on X86_64
1471 ---help---
1472 5-level paging enables access to larger address space:
1473 upto 128 PiB of virtual address space and 4 PiB of
1474 physical address space.
1475
1476 It will be supported by future Intel CPUs.
1477
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001478 A kernel with the option enabled can be booted on machines that
1479 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001480
1481 See Documentation/x86/x86_64/5level-paging.txt for more
1482 information.
1483
1484 Say N if unsure.
1485
Ingo Molnar10971ab2015-03-05 08:18:23 +01001486config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001487 def_bool y
Levin, Alexander (Sasha Levin)4675ff02017-11-15 17:36:02 -08001488 depends on X86_64 && !DEBUG_PAGEALLOC
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001489 ---help---
Ingo Molnar10971ab2015-03-05 08:18:23 +01001490 Certain kernel features effectively disable kernel
1491 linear 1 GB mappings (even if the CPU otherwise
1492 supports them), so don't confuse the user by printing
1493 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001494
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001495config X86_CPA_STATISTICS
1496 bool "Enable statistic for Change Page Attribute"
1497 depends on DEBUG_FS
1498 ---help---
1499 Expose statistics about the Change Page Attribute mechanims, which
Colin Ian Kinga9432452019-04-16 11:57:51 +01001500 helps to determine the effectiveness of preserving large and huge
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001501 page mappings when mapping protections are changed.
1502
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001503config ARCH_HAS_MEM_ENCRYPT
1504 def_bool y
1505
1506config AMD_MEM_ENCRYPT
1507 bool "AMD Secure Memory Encryption (SME) support"
1508 depends on X86_64 && CPU_SUP_AMD
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +03001509 select DYNAMIC_PHYSICAL_MASK
Ard Biesheuvelce9084b2019-02-02 10:41:17 +01001510 select ARCH_USE_MEMREMAP_PROT
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001511 ---help---
1512 Say yes to enable support for the encryption of system memory.
1513 This requires an AMD processor that supports Secure Memory
1514 Encryption (SME).
1515
1516config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1517 bool "Activate AMD Secure Memory Encryption (SME) by default"
1518 default y
1519 depends on AMD_MEM_ENCRYPT
1520 ---help---
1521 Say yes to have system memory encrypted by default if running on
1522 an AMD processor that supports Secure Memory Encryption (SME).
1523
1524 If set to Y, then the encryption of system memory can be
1525 deactivated with the mem_encrypt=off command line option.
1526
1527 If set to N, then the encryption of system memory can be
1528 activated with the mem_encrypt=on command line option.
1529
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001530# Common NUMA Features
1531config NUMA
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001532 bool "Numa Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001533 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001534 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1535 default y if X86_BIGSMP
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001536 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001537 Enable NUMA (Non Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001538
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001539 The kernel will try to allocate memory used by a CPU on the
1540 local memory controller of the CPU and add some more
1541 NUMA awareness to the kernel.
1542
Ingo Molnarc280ea52008-11-08 13:29:45 +01001543 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001544 (or later), AMD Opteron, or EM64T NUMA.
1545
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001546 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001547 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001548
1549 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001550
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001551config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001552 def_bool y
1553 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001554 depends on X86_64 && NUMA && PCI
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001555 ---help---
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001556 Enable AMD NUMA node topology detection. You should say Y here if
1557 you have a multi processor AMD system. This uses an old method to
1558 read the NUMA configuration directly from the builtin Northbridge
1559 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1560 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001561
1562config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001563 def_bool y
1564 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001565 depends on X86_64 && NUMA && ACPI && PCI
1566 select ACPI_NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001567 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001568 Enable ACPI SRAT based node topology detection.
1569
Suresh Siddha6ec6e0d2008-03-25 10:14:35 -07001570# Some NUMA nodes have memory ranges that span
1571# other nodes. Even though a pfn is valid and
1572# between a node's start and end pfns, it may not
1573# reside on that node. See memmap_init_zone()
1574# for details.
1575config NODES_SPAN_OTHER_NODES
1576 def_bool y
1577 depends on X86_64_ACPI_NUMA
1578
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001579config NUMA_EMU
1580 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001581 depends on NUMA
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001582 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001583 Enable NUMA emulation. A flat machine will be split
1584 into virtual nodes when booted with "numa=fake=N", where N is the
1585 number of nodes. This is only useful for debugging.
1586
1587config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001588 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001589 range 1 10
1590 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001591 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001592 default "3"
1593 depends on NEED_MULTIPLE_NODES
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001594 ---help---
Mike Travis1184dc22008-05-12 21:21:12 +02001595 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001596 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001597
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001598config ARCH_HAVE_MEMORY_PRESENT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001599 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001600 depends on X86_32 && DISCONTIGMEM
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001601
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001602config ARCH_FLATMEM_ENABLE
1603 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001604 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001605
1606config ARCH_DISCONTIGMEM_ENABLE
Mike Rapoport27921072019-04-24 16:24:12 +03001607 def_bool n
Christoph Lameterb2632952008-01-30 13:30:47 +01001608 depends on NUMA && X86_32
Mike Rapoport27921072019-04-24 16:24:12 +03001609 depends on BROKEN
Christoph Lameterb2632952008-01-30 13:30:47 +01001610
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001611config ARCH_SPARSEMEM_ENABLE
1612 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001613 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001614 select SPARSEMEM_STATIC if X86_32
1615 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1616
Tejun Heo3b166512011-04-01 11:15:12 +02001617config ARCH_SPARSEMEM_DEFAULT
Mike Rapoport6ad57f72019-04-24 16:24:11 +03001618 def_bool X86_64 || (NUMA && X86_32)
Tejun Heo3b166512011-04-01 11:15:12 +02001619
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001620config ARCH_SELECT_MEMORY_MODEL
1621 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001622 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001623
1624config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001625 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001626 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001627 help
1628 This option enables a sysfs memory/probe interface for testing.
1629 See Documentation/memory-hotplug.txt for more information.
1630 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001631
Tejun Heo3b166512011-04-01 11:15:12 +02001632config ARCH_PROC_KCORE_TEXT
1633 def_bool y
1634 depends on X86_64 && PROC_KCORE
1635
Avi Kivitya29815a2010-01-10 16:28:09 +02001636config ILLEGAL_POINTER_VALUE
1637 hex
1638 default 0 if X86_32
1639 default 0xdead000000000000 if X86_64
1640
Dan Williams7a678322015-08-19 00:34:34 -04001641config X86_PMEM_LEGACY_DEVICE
1642 bool
1643
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001644config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001645 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001646 depends on PHYS_ADDR_T_64BIT
1647 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001648 select X86_PMEM_LEGACY_DEVICE
Dan Williams9f53f9f2015-06-09 15:33:45 -04001649 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001650 help
1651 Treat memory marked using the non-standard e820 type of 12 as used
1652 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1653 The kernel will offer these regions to the 'pmem' driver so
1654 they can be used for persistent storage.
1655
1656 Say Y if unsure.
1657
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001658config HIGHPTE
1659 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001660 depends on HIGHMEM
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001661 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001662 The VM uses one page table entry for each page of physical memory.
1663 For systems with a lot of RAM, this can be wasteful of precious
1664 low memory. Setting this option will put user-space page table
1665 entries in high memory.
1666
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001667config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001668 bool "Check for low memory corruption"
1669 ---help---
1670 Periodically check for memory corruption in low memory, which
1671 is suspected to be caused by BIOS. Even when enabled in the
1672 configuration, it is disabled at runtime. Enable it by
1673 setting "memory_corruption_check=1" on the kernel command
1674 line. By default it scans the low 64k of memory every 60
1675 seconds; see the memory_corruption_check_size and
1676 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001677 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001678
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001679 When enabled with the default parameters, this option has
1680 almost no overhead, as it reserves a relatively small amount
1681 of memory and scans it infrequently. It both detects corruption
1682 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001683
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001684 It is, however, intended as a diagnostic tool; if repeatable
1685 BIOS-originated corruption always affects the same memory,
1686 you can use memmap= to prevent the kernel from using that
1687 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001688
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001689config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001690 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001691 depends on X86_CHECK_BIOS_CORRUPTION
1692 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001693 ---help---
1694 Set whether the default state of memory_corruption_check is
1695 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001696
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001697config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001698 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1699 default 64
1700 range 4 640
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001701 ---help---
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001702 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001703
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001704 The first page contains BIOS data structures that the kernel
1705 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001706
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001707 By default we reserve the first 64K of physical RAM, as a
1708 number of BIOSes are known to corrupt that memory range
1709 during events such as suspend/resume or monitor cable
1710 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001711
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001712 You can set this to 4 if you are absolutely sure that you
1713 trust the BIOS to get all its memory reservations and usages
1714 right. If you know your BIOS have problems beyond the
1715 default 64K area, you can set this to 640 to avoid using the
1716 entire low memory range.
1717
1718 If you have doubts about the BIOS (e.g. suspend/resume does
1719 not work or there's kernel crashes after certain hardware
1720 hotplug events) then you might want to enable
1721 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1722 typical corruption patterns.
1723
1724 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001725
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001726config MATH_EMULATION
1727 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001728 depends on MODIFY_LDT_SYSCALL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001729 prompt "Math emulation" if X86_32
1730 ---help---
1731 Linux can emulate a math coprocessor (used for floating point
1732 operations) if you don't have one. 486DX and Pentium processors have
1733 a math coprocessor built in, 486SX and 386 do not, unless you added
1734 a 487DX or 387, respectively. (The messages during boot time can
1735 give you some hints here ["man dmesg"].) Everyone needs either a
1736 coprocessor or this emulation.
1737
1738 If you don't have a math coprocessor, you need to say Y here; if you
1739 say Y here even though you have a coprocessor, the coprocessor will
1740 be used nevertheless. (This behavior can be changed with the kernel
1741 command line option "no387", which comes handy if your coprocessor
1742 is broken. Try "man bootparam" or see the documentation of your boot
1743 loader (lilo or loadlin) about how to pass options to the kernel at
1744 boot time.) This means that it is a good idea to say Y here if you
1745 intend to use this kernel on different machines.
1746
1747 More information about the internals of the Linux math coprocessor
1748 emulation can be found in <file:arch/x86/math-emu/README>.
1749
1750 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1751 kernel, it won't hurt.
1752
1753config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001754 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001755 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001756 ---help---
1757 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1758 the Memory Type Range Registers (MTRRs) may be used to control
1759 processor access to memory ranges. This is most useful if you have
1760 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1761 allows bus write transfers to be combined into a larger transfer
1762 before bursting over the PCI/AGP bus. This can increase performance
1763 of image write operations 2.5 times or more. Saying Y here creates a
1764 /proc/mtrr file which may be used to manipulate your processor's
1765 MTRRs. Typically the X server should use this.
1766
1767 This code has a reasonably generic interface so that similar
1768 control registers on other processors can be easily supported
1769 as well:
1770
1771 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1772 Registers (ARRs) which provide a similar functionality to MTRRs. For
1773 these, the ARRs are used to emulate the MTRRs.
1774 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1775 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1776 write-combining. All of these processors are supported by this code
1777 and it makes sense to say Y here if you have one of them.
1778
1779 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1780 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1781 can lead to all sorts of problems, so it's good to say Y here.
1782
1783 You can safely say Y even if your machine doesn't have MTRRs, you'll
1784 just add about 9 KB to your kernel.
1785
Randy Dunlap7225e752008-07-26 17:54:22 -07001786 See <file:Documentation/x86/mtrr.txt> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001787
Yinghai Lu95ffa242008-04-29 03:52:33 -07001788config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001789 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001790 prompt "MTRR cleanup support"
1791 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001792 ---help---
Thomas Gleixneraba37282008-07-15 14:48:48 +02001793 Convert MTRR layout from continuous to discrete, so X drivers can
1794 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001795
Thomas Gleixneraba37282008-07-15 14:48:48 +02001796 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001797 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001798 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001799
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001800 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001801
1802config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001803 int "MTRR cleanup enable value (0-1)"
1804 range 0 1
1805 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001806 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001807 ---help---
Yinghai Luf5098d62008-04-29 20:25:58 -07001808 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001809
Yinghai Lu12031a62008-05-02 02:40:22 -07001810config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1811 int "MTRR cleanup spare reg num (0-7)"
1812 range 0 7
1813 default "1"
1814 depends on MTRR_SANITIZER
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001815 ---help---
Yinghai Lu12031a62008-05-02 02:40:22 -07001816 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001817 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001818
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001819config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001820 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001821 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001822 depends on MTRR
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001823 ---help---
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001824 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001825
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001826 PATs are the modern equivalents of MTRRs and are much more
1827 flexible than MTRRs.
1828
1829 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001830 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001831
1832 If unsure, say Y.
1833
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001834config ARCH_USES_PG_UNCACHED
1835 def_bool y
1836 depends on X86_PAT
1837
H. Peter Anvin628c6242011-07-31 13:59:29 -07001838config ARCH_RANDOM
1839 def_bool y
1840 prompt "x86 architectural random number generator" if EXPERT
1841 ---help---
1842 Enable the x86 architectural RDRAND instruction
1843 (Intel Bull Mountain technology) to generate random numbers.
1844 If supported, this is a high bandwidth, cryptographically
1845 secure hardware random number generator.
1846
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001847config X86_SMAP
1848 def_bool y
1849 prompt "Supervisor Mode Access Prevention" if EXPERT
1850 ---help---
1851 Supervisor Mode Access Prevention (SMAP) is a security
1852 feature in newer Intel processors. There is a small
1853 performance cost if this enabled and turned on; there is
1854 also a small increase in the kernel size if this is enabled.
1855
1856 If unsure, say Y.
1857
Ricardo Neriaa35f892017-11-05 18:27:54 -08001858config X86_INTEL_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001859 def_bool y
Ricardo Neriaa35f892017-11-05 18:27:54 -08001860 depends on CPU_SUP_INTEL
1861 prompt "Intel User Mode Instruction Prevention" if EXPERT
1862 ---help---
1863 The User Mode Instruction Prevention (UMIP) is a security
1864 feature in newer Intel processors. If enabled, a general
Ricardo Neri796ebc82017-11-13 22:29:42 -08001865 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1866 or STR instructions are executed in user mode. These instructions
1867 unnecessarily expose information about the hardware state.
1868
1869 The vast majority of applications do not use these instructions.
1870 For the very few that do, software emulation is provided in
1871 specific cases in protected and virtual-8086 modes. Emulated
1872 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001873
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001874config X86_INTEL_MPX
1875 prompt "Intel MPX (Memory Protection Extensions)"
1876 def_bool n
Rik van Rieldf3735c2017-09-06 16:25:11 -07001877 # Note: only available in 64-bit mode due to VMA flags shortage
1878 depends on CPU_SUP_INTEL && X86_64
1879 select ARCH_USES_HIGH_VMA_FLAGS
Dave Hansen72e9b5f2014-12-12 10:38:36 -08001880 ---help---
1881 MPX provides hardware features that can be used in
1882 conjunction with compiler-instrumented code to check
1883 memory references. It is designed to detect buffer
1884 overflow or underflow bugs.
1885
1886 This option enables running applications which are
1887 instrumented or otherwise use MPX. It does not use MPX
1888 itself inside the kernel or to protect the kernel
1889 against bad memory references.
1890
1891 Enabling this option will make the kernel larger:
1892 ~8k of kernel text and 36 bytes of data on a 64-bit
1893 defconfig. It adds a long to the 'mm_struct' which
1894 will increase the kernel memory overhead of each
1895 process and adds some branches to paths used during
1896 exec() and munmap().
1897
1898 For details, see Documentation/x86/intel_mpx.txt
1899
1900 If unsure, say N.
1901
Dave Hansen35e97792016-02-12 13:02:00 -08001902config X86_INTEL_MEMORY_PROTECTION_KEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001903 prompt "Intel Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001904 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001905 # Note: only available in 64-bit mode
Dave Hansen35e97792016-02-12 13:02:00 -08001906 depends on CPU_SUP_INTEL && X86_64
Ingo Molnar52c8e602016-11-15 10:15:03 +01001907 select ARCH_USES_HIGH_VMA_FLAGS
1908 select ARCH_HAS_PKEYS
Dave Hansen284244a2016-02-12 13:02:28 -08001909 ---help---
1910 Memory Protection Keys provides a mechanism for enforcing
1911 page-based protections, but without requiring modification of the
1912 page tables when an application changes protection domains.
1913
1914 For details, see Documentation/x86/protection-keys.txt
1915
1916 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001917
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001918config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001919 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001920 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001921 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001922 select EFI_RUNTIME_WRAPPERS
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001923 ---help---
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001924 This enables the kernel to use EFI runtime services that are
1925 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001926
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001927 This option is only useful on systems that have EFI firmware.
1928 In addition, you should use the latest ELILO loader available
1929 at <http://elilo.sourceforge.net> in order to take advantage
1930 of EFI runtime services. However, even with this option, the
1931 resultant kernel should continue to boot on existing non-EFI
1932 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001933
Matt Fleming291f3632011-12-12 21:27:52 +00001934config EFI_STUB
1935 bool "EFI stub support"
Matt Flemingb16d8c22014-08-05 00:12:19 +01001936 depends on EFI && !X86_USE_3DNOW
Matt Fleming7b2a5832014-07-11 08:45:25 +01001937 select RELOCATABLE
Matt Fleming291f3632011-12-12 21:27:52 +00001938 ---help---
1939 This kernel feature allows a bzImage to be loaded directly
1940 by EFI firmware without the use of a bootloader.
1941
Roy Franz4172fe22013-09-22 15:45:25 -07001942 See Documentation/efi-stub.txt for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001943
Matt Fleming7d453ee2014-01-10 18:52:06 +00001944config EFI_MIXED
1945 bool "EFI mixed-mode support"
1946 depends on EFI_STUB && X86_64
1947 ---help---
1948 Enabling this feature allows a 64-bit kernel to be booted
1949 on a 32-bit firmware, provided that your CPU supports 64-bit
1950 mode.
1951
1952 Note that it is not possible to boot a mixed-mode enabled
1953 kernel via the EFI boot stub - a bootloader that supports
1954 the EFI handover protocol must be used.
1955
1956 If unsure, say N.
1957
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001958config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001959 def_bool y
1960 prompt "Enable seccomp to safely compute untrusted bytecode"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001961 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001962 This kernel feature is useful for number crunching applications
1963 that may need to compute untrusted bytecode during their
1964 execution. By using pipes or other transports made available to
1965 the process as file descriptors supporting the read/write
1966 syscalls, it's possible to isolate those applications in
1967 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001968 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001969 and the task is only allowed to execute a few safe syscalls
1970 defined by each seccomp mode.
1971
1972 If unsure, say Y. Only embedded should say N here.
1973
Masahiro Yamada8636a1f2018-12-11 20:01:04 +09001974source "kernel/Kconfig.hz"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001975
1976config KEXEC
1977 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001978 select KEXEC_CORE
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001979 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001980 kexec is a system call that implements the ability to shutdown your
1981 current kernel, and to start another kernel. It is like a reboot
1982 but it is independent of the system firmware. And like a reboot
1983 you can start any kernel with it, not just Linux.
1984
1985 The name comes from the similarity to the exec system call.
1986
1987 It is an ongoing process to be certain the hardware in a machine
1988 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02001989 initially work for you. As of this writing the exact hardware
1990 interface is strongly in flux, so no good recommendation can be
1991 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001992
Vivek Goyal74ca3172014-08-29 15:18:46 -07001993config KEXEC_FILE
1994 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07001995 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07001996 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07001997 depends on X86_64
1998 depends on CRYPTO=y
1999 depends on CRYPTO_SHA256=y
2000 ---help---
2001 This is new version of kexec system call. This system call is
2002 file based and takes file descriptors as system call argument
2003 for kernel and initramfs as opposed to list of segments as
2004 accepted by previous system call.
2005
AKASHI Takahirob799a092018-04-13 15:35:45 -07002006config ARCH_HAS_KEXEC_PURGATORY
2007 def_bool KEXEC_FILE
2008
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002009config KEXEC_VERIFY_SIG
2010 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07002011 depends on KEXEC_FILE
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002012 ---help---
2013 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002014 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002015
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002016 In addition to that option, you need to enable signature
2017 verification for the corresponding kernel image type being
2018 loaded in order for this to work.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002019
2020config KEXEC_BZIMAGE_VERIFY_SIG
2021 bool "Enable bzImage signature verification support"
2022 depends on KEXEC_VERIFY_SIG
2023 depends on SIGNED_PE_FILE_VERIFICATION
2024 select SYSTEM_TRUSTED_KEYRING
2025 ---help---
2026 Enable bzImage signature verification support.
2027
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002028config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002029 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002030 depends on X86_64 || (X86_32 && HIGHMEM)
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002031 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002032 Generate crash dump after being started by kexec.
2033 This should be normally only set in special crash dump kernels
2034 which are loaded in the main kernel with kexec-tools into
2035 a specially reserved region and then later executed after
2036 a crash by kdump/kexec. The crash dump kernel must be compiled
2037 to a memory address not used by the main kernel or BIOS using
2038 PHYSICAL_START, or it must be built as a relocatable image
2039 (CONFIG_RELOCATABLE=y).
2040 For more details see Documentation/kdump/kdump.txt
2041
Huang Ying3ab83522008-07-25 19:45:07 -07002042config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002043 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002044 depends on KEXEC && HIBERNATION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002045 ---help---
Huang Ying89081d12008-07-25 19:45:10 -07002046 Jump between original kernel and kexeced kernel and invoke
2047 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002048
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002049config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002050 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002051 default "0x1000000"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002052 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002053 This gives the physical address where the kernel is loaded.
2054
2055 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2056 bzImage will decompress itself to above physical address and
2057 run from there. Otherwise, bzImage will run from the address where
2058 it has been loaded by the boot loader and will ignore above physical
2059 address.
2060
2061 In normal kdump cases one does not have to set/change this option
2062 as now bzImage can be compiled as a completely relocatable image
2063 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2064 address. This option is mainly useful for the folks who don't want
2065 to use a bzImage for capturing the crash dump and want to use a
2066 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2067 to be specifically compiled to run from a specific memory area
2068 (normally a reserved region) and this option comes handy.
2069
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002070 So if you are using bzImage for capturing the crash dump,
2071 leave the value here unchanged to 0x1000000 and set
2072 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2073 for capturing the crash dump change this value to start of
2074 the reserved region. In other words, it can be set based on
2075 the "X" value as specified in the "crashkernel=YM@XM"
2076 command line boot parameter passed to the panic-ed
2077 kernel. Please take a look at Documentation/kdump/kdump.txt
2078 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002079
2080 Usage of bzImage for capturing the crash dump is recommended as
2081 one does not have to build two kernels. Same kernel can be used
2082 as production kernel and capture kernel. Above option should have
2083 gone away after relocatable bzImage support is introduced. But it
2084 is present because there are users out there who continue to use
2085 vmlinux for dump capture. This option should go away down the
2086 line.
2087
2088 Don't change this unless you know what you are doing.
2089
2090config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002091 bool "Build a relocatable kernel"
2092 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002093 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002094 This builds a kernel image that retains relocation information
2095 so it can be loaded someplace besides the default 1MB.
2096 The relocations tend to make the kernel binary about 10% larger,
2097 but are discarded at runtime.
2098
2099 One use is for the kexec on panic case where the recovery kernel
2100 must live at a different physical address than the primary
2101 kernel.
2102
2103 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2104 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002105 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002106
Kees Cook8ab38202013-10-10 17:18:14 -07002107config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002108 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002109 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002110 default y
Kees Cook8ab38202013-10-10 17:18:14 -07002111 ---help---
Baoquan Hee8581e32016-04-20 13:55:43 -07002112 In support of Kernel Address Space Layout Randomization (KASLR),
2113 this randomizes the physical address at which the kernel image
2114 is decompressed and the virtual address where the kernel
2115 image is mapped, as a security feature that deters exploit
2116 attempts relying on knowledge of the location of kernel
2117 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002118
Kees Cooked9f0072016-05-25 15:45:33 -07002119 On 64-bit, the kernel physical and virtual addresses are
2120 randomized separately. The physical address will be anywhere
2121 between 16MB and the top of physical memory (up to 64TB). The
2122 virtual address will be randomized from 16MB up to 1GB (9 bits
2123 of entropy). Note that this also reduces the memory space
2124 available to kernel modules from 1.5GB to 1GB.
2125
2126 On 32-bit, the kernel physical and virtual addresses are
2127 randomized together. They will be randomized from 16MB up to
2128 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002129
Baoquan Hee8581e32016-04-20 13:55:43 -07002130 Entropy is generated using the RDRAND instruction if it is
2131 supported. If RDTSC is supported, its value is mixed into
2132 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002133 supported, then entropy is read from the i8254 timer. The
2134 usable entropy is limited by the kernel being built using
2135 2GB addressing, and that PHYSICAL_ALIGN must be at a
2136 minimum of 2MB. As a result, only 10 bits of entropy are
2137 theoretically possible, but the implementations are further
2138 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002139
Ingo Molnar6807c842017-04-18 11:08:12 +02002140 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002141
2142# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002143config X86_NEED_RELOCS
2144 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002145 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002146
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002147config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002148 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002149 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002150 range 0x2000 0x1000000 if X86_32
2151 range 0x200000 0x1000000 if X86_64
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002152 ---help---
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002153 This value puts the alignment restrictions on physical address
2154 where kernel is loaded and run from. Kernel is compiled for an
2155 address which meets above alignment restriction.
2156
2157 If bootloader loads the kernel at a non-aligned address and
2158 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2159 address aligned to above value and run from there.
2160
2161 If bootloader loads the kernel at a non-aligned address and
2162 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2163 load address and decompress itself to the address it has been
2164 compiled for and run from there. The address for which kernel is
2165 compiled already meets above alignment restrictions. Hence the
2166 end result is that kernel runs from a physical address meeting
2167 above alignment restrictions.
2168
Kees Cooka0215062013-07-08 09:15:17 -07002169 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2170 this value must be a multiple of 0x200000.
2171
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002172 Don't change this unless you know what you are doing.
2173
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002174config DYNAMIC_MEMORY_LAYOUT
2175 bool
2176 ---help---
2177 This option makes base addresses of vmalloc and vmemmap as well as
2178 __PAGE_OFFSET movable during boot.
2179
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002180config RANDOMIZE_MEMORY
2181 bool "Randomize the kernel memory sections"
2182 depends on X86_64
2183 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002184 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002185 default RANDOMIZE_BASE
2186 ---help---
2187 Randomizes the base virtual address of kernel memory sections
2188 (physical memory mapping, vmalloc & vmemmap). This security feature
2189 makes exploits relying on predictable memory locations less reliable.
2190
2191 The order of allocations remains unchanged. Entropy is generated in
2192 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2193 configuration have in average 30,000 different possible virtual
2194 addresses for each memory section.
2195
Ingo Molnar6807c842017-04-18 11:08:12 +02002196 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002197
Thomas Garnier90397a42016-06-21 17:47:06 -07002198config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2199 hex "Physical memory mapping padding" if EXPERT
2200 depends on RANDOMIZE_MEMORY
2201 default "0xa" if MEMORY_HOTPLUG
2202 default "0x0"
2203 range 0x1 0x40 if MEMORY_HOTPLUG
2204 range 0x0 0x40
2205 ---help---
2206 Define the padding in terabytes added to the existing physical
2207 memory size during kernel memory randomization. It is useful
2208 for memory hotplug support but reduces the entropy available for
2209 address randomization.
2210
2211 If unsure, leave at the default value.
2212
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002213config HOTPLUG_CPU
Thomas Gleixnerbebd0242019-03-26 17:36:06 +01002214 def_bool y
Stephen Rothwell40b31362013-05-21 13:49:35 +10002215 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002216
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002217config BOOTPARAM_HOTPLUG_CPU0
2218 bool "Set default setting of cpu0_hotpluggable"
Kees Cook2c922cd2013-01-22 13:01:19 -08002219 depends on HOTPLUG_CPU
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002220 ---help---
2221 Set whether default state of cpu0_hotpluggable is on or off.
2222
2223 Say Y here to enable CPU0 hotplug by default. If this switch
2224 is turned on, there is no need to give cpu0_hotplug kernel
2225 parameter and the CPU0 hotplug feature is enabled by default.
2226
2227 Please note: there are two known CPU0 dependencies if you want
2228 to enable the CPU0 hotplug feature either by this switch or by
2229 cpu0_hotplug kernel parameter.
2230
2231 First, resume from hibernate or suspend always starts from CPU0.
2232 So hibernate and suspend are prevented if CPU0 is offline.
2233
2234 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2235 offline if any interrupt can not migrate out of CPU0. There may
2236 be other CPU0 dependencies.
2237
2238 Please make sure the dependencies are under your control before
2239 you enable this feature.
2240
2241 Say N if you don't want to enable CPU0 hotplug feature by default.
2242 You still can enable the CPU0 hotplug feature at boot by kernel
2243 parameter cpu0_hotplug.
2244
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002245config DEBUG_HOTPLUG_CPU0
2246 def_bool n
2247 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002248 depends on HOTPLUG_CPU
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002249 ---help---
2250 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2251 soon as possible and boots up userspace with CPU0 offlined. User
2252 can online CPU0 back after boot time.
2253
2254 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2255 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2256 compilation or giving cpu0_hotplug kernel parameter at boot.
2257
2258 If unsure, say N.
2259
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002260config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002261 def_bool n
2262 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002263 depends on COMPAT_32
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002264 ---help---
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002265 Certain buggy versions of glibc will crash if they are
2266 presented with a 32-bit vDSO that is not mapped at the address
2267 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002268
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002269 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2270 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2271 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2272 the only released version with the bug, but OpenSUSE 9
2273 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002274
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002275 The symptom of the bug is that everything crashes on startup, saying:
2276 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2277
2278 Saying Y here changes the default value of the vdso32 boot
2279 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2280 This works around the glibc bug but hurts performance.
2281
2282 If unsure, say N: if you are compiling your own kernel, you
2283 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002284
Kees Cook3dc33bd2015-08-12 17:55:19 -07002285choice
2286 prompt "vsyscall table for legacy applications"
2287 depends on X86_64
2288 default LEGACY_VSYSCALL_EMULATE
2289 help
2290 Legacy user code that does not know how to find the vDSO expects
2291 to be able to issue three syscalls by calling fixed addresses in
2292 kernel space. Since this location is not randomized with ASLR,
2293 it can be used to assist security vulnerability exploitation.
2294
2295 This setting can be changed at boot time via the kernel command
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002296 line parameter vsyscall=[emulate|xonly|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002297
2298 On a system with recent enough glibc (2.14 or newer) and no
2299 static binaries, you can say None without a performance penalty
2300 to improve security.
2301
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002302 If unsure, select "Emulate execution only".
Kees Cook3dc33bd2015-08-12 17:55:19 -07002303
Kees Cook3dc33bd2015-08-12 17:55:19 -07002304 config LEGACY_VSYSCALL_EMULATE
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002305 bool "Full emulation"
Kees Cook3dc33bd2015-08-12 17:55:19 -07002306 help
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002307 The kernel traps and emulates calls into the fixed vsyscall
2308 address mapping. This makes the mapping non-executable, but
2309 it still contains readable known contents, which could be
2310 used in certain rare security vulnerability exploits. This
2311 configuration is recommended when using legacy userspace
2312 that still uses vsyscalls along with legacy binary
2313 instrumentation tools that require code to be readable.
2314
2315 An example of this type of legacy userspace is running
2316 Pin on an old binary that still uses vsyscalls.
2317
2318 config LEGACY_VSYSCALL_XONLY
2319 bool "Emulate execution only"
2320 help
2321 The kernel traps and emulates calls into the fixed vsyscall
2322 address mapping and does not allow reads. This
2323 configuration is recommended when userspace might use the
2324 legacy vsyscall area but support for legacy binary
2325 instrumentation of legacy code is not needed. It mitigates
2326 certain uses of the vsyscall area as an ASLR-bypassing
2327 buffer.
Kees Cook3dc33bd2015-08-12 17:55:19 -07002328
2329 config LEGACY_VSYSCALL_NONE
2330 bool "None"
2331 help
2332 There will be no vsyscall mapping at all. This will
2333 eliminate any risk of ASLR bypass due to the vsyscall
2334 fixed address mapping. Attempts to use the vsyscalls
2335 will be reported to dmesg, so that either old or
2336 malicious userspace programs can be identified.
2337
2338endchoice
2339
Tim Bird516cbf32008-08-12 12:52:36 -07002340config CMDLINE_BOOL
2341 bool "Built-in kernel command line"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002342 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002343 Allow for specifying boot arguments to the kernel at
2344 build time. On some systems (e.g. embedded ones), it is
2345 necessary or convenient to provide some or all of the
2346 kernel boot arguments with the kernel itself (that is,
2347 to not rely on the boot loader to provide them.)
2348
2349 To compile command line arguments into the kernel,
2350 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002351 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002352
2353 Systems with fully functional boot loaders (i.e. non-embedded)
2354 should leave this option set to 'N'.
2355
2356config CMDLINE
2357 string "Built-in kernel command string"
2358 depends on CMDLINE_BOOL
2359 default ""
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002360 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002361 Enter arguments here that should be compiled into the kernel
2362 image and used at boot time. If the boot loader provides a
2363 command line at boot time, it is appended to this string to
2364 form the full kernel command line, when the system boots.
2365
2366 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2367 change this behavior.
2368
2369 In most cases, the command line (whether built-in or provided
2370 by the boot loader) should specify the device for the root
2371 file system.
2372
2373config CMDLINE_OVERRIDE
2374 bool "Built-in command line overrides boot loader arguments"
Tim Bird516cbf32008-08-12 12:52:36 -07002375 depends on CMDLINE_BOOL
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002376 ---help---
Tim Bird516cbf32008-08-12 12:52:36 -07002377 Set this option to 'Y' to have the kernel ignore the boot loader
2378 command line, and use ONLY the built-in command line.
2379
2380 This is used to work around broken boot loaders. This should
2381 be set to 'N' under normal conditions.
2382
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002383config MODIFY_LDT_SYSCALL
2384 bool "Enable the LDT (local descriptor table)" if EXPERT
2385 default y
2386 ---help---
2387 Linux can allow user programs to install a per-process x86
2388 Local Descriptor Table (LDT) using the modify_ldt(2) system
2389 call. This is required to run 16-bit or segmented code such as
2390 DOSEMU or some Wine programs. It is also used by some very old
2391 threading libraries.
2392
2393 Enabling this feature adds a small amount of overhead to
2394 context switches and increases the low-level kernel attack
2395 surface. Disabling it removes the modify_ldt(2) system call.
2396
2397 Saying 'N' here may make sense for embedded or server kernels.
2398
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002399source "kernel/livepatch/Kconfig"
2400
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002401endmenu
2402
Michal Hocko3072e412017-09-08 16:11:39 -07002403config ARCH_HAS_ADD_PAGES
2404 def_bool y
2405 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2406
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002407config ARCH_ENABLE_MEMORY_HOTPLUG
2408 def_bool y
2409 depends on X86_64 || (X86_32 && HIGHMEM)
2410
Gary Hade35551052008-10-31 10:52:03 -07002411config ARCH_ENABLE_MEMORY_HOTREMOVE
2412 def_bool y
2413 depends on MEMORY_HOTPLUG
2414
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002415config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002416 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002417 depends on NUMA
2418
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002419config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2420 def_bool y
2421 depends on X86_64 || X86_PAE
2422
Naoya Horiguchic177c812014-06-04 16:05:35 -07002423config ARCH_ENABLE_HUGEPAGE_MIGRATION
2424 def_bool y
2425 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2426
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002427config ARCH_ENABLE_THP_MIGRATION
2428 def_bool y
2429 depends on X86_64 && TRANSPARENT_HUGEPAGE
2430
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002431menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002432
2433config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002434 def_bool y
Zhimin Gu44556532018-09-21 14:27:29 +08002435 depends on HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002436
2437source "kernel/power/Kconfig"
2438
2439source "drivers/acpi/Kconfig"
2440
Feng Tangefafc8b2009-08-14 15:23:29 -04002441source "drivers/sfi/Kconfig"
2442
Andi Kleena6b68072008-01-30 13:32:49 +01002443config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002444 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002445 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002446
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002447menuconfig APM
2448 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002449 depends on X86_32 && PM_SLEEP
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002450 ---help---
2451 APM is a BIOS specification for saving power using several different
2452 techniques. This is mostly useful for battery powered laptops with
2453 APM compliant BIOSes. If you say Y here, the system time will be
2454 reset after a RESUME operation, the /proc/apm device will provide
2455 battery status information, and user-space programs will receive
2456 notification of APM "events" (e.g. battery status change).
2457
2458 If you select "Y" here, you can disable actual use of the APM
2459 BIOS by passing the "apm=off" option to the kernel at boot time.
2460
2461 Note that the APM support is almost completely disabled for
2462 machines with more than one CPU.
2463
2464 In order to use APM, you will need supporting software. For location
Michael Witten2dc98fd2011-07-08 21:11:16 +00002465 and more information, read <file:Documentation/power/apm-acpi.txt>
2466 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002467 <http://www.tldp.org/docs.html#howto>.
2468
2469 This driver does not spin down disk drives (see the hdparm(8)
2470 manpage ("man 8 hdparm") for that), and it doesn't turn off
2471 VESA-compliant "green" monitors.
2472
2473 This driver does not support the TI 4000M TravelMate and the ACER
2474 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2475 desktop machines also don't have compliant BIOSes, and this driver
2476 may cause those machines to panic during the boot phase.
2477
2478 Generally, if you don't have a battery in your machine, there isn't
2479 much point in using this driver and you should say N. If you get
2480 random kernel OOPSes or reboots that don't seem to be related to
2481 anything, try disabling/enabling this option (or disabling/enabling
2482 APM in your BIOS).
2483
2484 Some other things you should try when experiencing seemingly random,
2485 "weird" problems:
2486
2487 1) make sure that you have enough swap space and that it is
2488 enabled.
2489 2) pass the "no-hlt" option to the kernel
2490 3) switch on floating point emulation in the kernel and pass
2491 the "no387" option to the kernel
2492 4) pass the "floppy=nodma" option to the kernel
2493 5) pass the "mem=4M" option to the kernel (thereby disabling
2494 all but the first 4 MB of RAM)
2495 6) make sure that the CPU is not over clocked.
2496 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2497 8) disable the cache from your BIOS settings
2498 9) install a fan for the video card or exchange video RAM
2499 10) install a better fan for the CPU
2500 11) exchange RAM chips
2501 12) exchange the motherboard.
2502
2503 To compile this driver as a module, choose M here: the
2504 module will be called apm.
2505
2506if APM
2507
2508config APM_IGNORE_USER_SUSPEND
2509 bool "Ignore USER SUSPEND"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002510 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002511 This option will ignore USER SUSPEND requests. On machines with a
2512 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2513 series notebooks, it is necessary to say Y because of a BIOS bug.
2514
2515config APM_DO_ENABLE
2516 bool "Enable PM at boot time"
2517 ---help---
2518 Enable APM features at boot time. From page 36 of the APM BIOS
2519 specification: "When disabled, the APM BIOS does not automatically
2520 power manage devices, enter the Standby State, enter the Suspend
2521 State, or take power saving steps in response to CPU Idle calls."
2522 This driver will make CPU Idle calls when Linux is idle (unless this
2523 feature is turned off -- see "Do CPU IDLE calls", below). This
2524 should always save battery power, but more complicated APM features
2525 will be dependent on your BIOS implementation. You may need to turn
2526 this option off if your computer hangs at boot time when using APM
2527 support, or if it beeps continuously instead of suspending. Turn
2528 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2529 T400CDT. This is off by default since most machines do fine without
2530 this feature.
2531
2532config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002533 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002534 bool "Make CPU Idle calls when idle"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002535 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002536 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2537 On some machines, this can activate improved power savings, such as
2538 a slowed CPU clock rate, when the machine is idle. These idle calls
2539 are made after the idle loop has run for some length of time (e.g.,
2540 333 mS). On some machines, this will cause a hang at boot time or
2541 whenever the CPU becomes idle. (On machines with more than one CPU,
2542 this option does nothing.)
2543
2544config APM_DISPLAY_BLANK
2545 bool "Enable console blanking using APM"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002546 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002547 Enable console blanking using the APM. Some laptops can use this to
2548 turn off the LCD backlight when the screen blanker of the Linux
2549 virtual console blanks the screen. Note that this is only used by
2550 the virtual console screen blanker, and won't turn off the backlight
2551 when using the X Window system. This also doesn't have anything to
2552 do with your VESA-compliant power-saving monitor. Further, this
2553 option doesn't work for all laptops -- it might not turn off your
2554 backlight at all, or it might print a lot of errors to the console,
2555 especially if you are using gpm.
2556
2557config APM_ALLOW_INTS
2558 bool "Allow interrupts during APM BIOS calls"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002559 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002560 Normally we disable external interrupts while we are making calls to
2561 the APM BIOS as a measure to lessen the effects of a badly behaving
2562 BIOS implementation. The BIOS should reenable interrupts if it
2563 needs to. Unfortunately, some BIOSes do not -- especially those in
2564 many of the newer IBM Thinkpads. If you experience hangs when you
2565 suspend, try setting this to Y. Otherwise, say N.
2566
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002567endif # APM
2568
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002569source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002570
2571source "drivers/cpuidle/Kconfig"
2572
Andy Henroid27471fd2008-10-09 11:45:22 -07002573source "drivers/idle/Kconfig"
2574
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002575endmenu
2576
2577
2578menu "Bus options (PCI etc.)"
2579
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002580choice
2581 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002582 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002583 default PCI_GOANY
2584 ---help---
2585 On PCI systems, the BIOS can be used to detect the PCI devices and
2586 determine their configuration. However, some old PCI motherboards
2587 have BIOS bugs and may crash if this is done. Also, some embedded
2588 PCI-based systems don't have any BIOS at all. Linux can also try to
2589 detect the PCI hardware directly without using the BIOS.
2590
2591 With this option, you can specify how Linux should detect the
2592 PCI devices. If you choose "BIOS", the BIOS will be used,
2593 if you choose "Direct", the BIOS won't be used, and if you
2594 choose "MMConfig", then PCI Express MMCONFIG will be used.
2595 If you choose "Any", the kernel will try MMCONFIG, then the
2596 direct access method and falls back to the BIOS if that doesn't
2597 work. If unsure, go with the default, which is "Any".
2598
2599config PCI_GOBIOS
2600 bool "BIOS"
2601
2602config PCI_GOMMCONFIG
2603 bool "MMConfig"
2604
2605config PCI_GODIRECT
2606 bool "Direct"
2607
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002608config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002609 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002610 depends on OLPC
2611
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002612config PCI_GOANY
2613 bool "Any"
2614
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002615endchoice
2616
2617config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002618 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002619 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002620
2621# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2622config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002623 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002624 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002625
2626config PCI_MMCONFIG
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002627 bool "Support mmconfig PCI config space access" if X86_64
2628 default y
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002629 depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002630 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002631
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002632config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002633 def_bool y
2634 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002635
Alex Nixonb5401a92010-03-18 16:31:34 -04002636config PCI_XEN
2637 def_bool y
2638 depends on PCI && XEN
2639 select SWIOTLB_XEN
2640
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002641config MMCONF_FAM10H
2642 def_bool y
2643 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002644
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002645config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002646 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002647 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002648 help
2649 Read the PCI windows out of the CNB20LE host bridge. This allows
2650 PCI hotplug to work on systems with the CNB20LE chipset which do
2651 not have ACPI.
2652
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002653 There's no public spec for this chipset, and this functionality
2654 is known to be incomplete.
2655
2656 You should say N unless you know you need this.
2657
William Breathitt Gray3a495512016-05-27 18:08:27 -04002658config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002659 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002660 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002661 Expose ISA bus device drivers and options available for selection and
2662 configuration. Enable this option if your target machine has an ISA
2663 bus. ISA is an older system, displaced by PCI and newer bus
2664 architectures -- if your target machine is modern, it probably does
2665 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002666
2667 If unsure, say N.
2668
David Rientjes1c00f012011-03-22 16:34:59 -07002669# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002670config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002671 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2672 default y
2673 help
2674 Enables ISA-style DMA support for devices requiring such controllers.
2675 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002676
Linus Torvalds51e68d02016-05-21 10:25:19 -07002677if X86_32
2678
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002679config ISA
2680 bool "ISA support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002681 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002682 Find out whether you have ISA slots on your motherboard. ISA is the
2683 name of a bus system, i.e. the way the CPU talks to the other stuff
2684 inside your box. Other bus systems are PCI, EISA, MicroChannel
2685 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2686 newer boards don't support it. If you have ISA, say Y, otherwise N.
2687
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002688config SCx200
2689 tristate "NatSemi SCx200 support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002690 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002691 This provides basic support for National Semiconductor's
2692 (now AMD's) Geode processors. The driver probes for the
2693 PCI-IDs of several on-chip devices, so its a good dependency
2694 for other scx200_* drivers.
2695
2696 If compiled as a module, the driver is named scx200.
2697
2698config SCx200HR_TIMER
2699 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002700 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002701 default y
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002702 ---help---
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002703 This driver provides a clocksource built upon the on-chip
2704 27MHz high-resolution timer. Its also a workaround for
2705 NSC Geode SC-1100's buggy TSC, which loses time when the
2706 processor goes idle (as is done by the scheduler). The
2707 other workaround is idle=poll boot option.
2708
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002709config OLPC
2710 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002711 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002712 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002713 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002714 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002715 select IRQ_DOMAIN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002716 ---help---
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002717 Add support for detecting the unique features of the OLPC
2718 XO hardware.
2719
Daniel Drakea3128582011-06-25 17:34:10 +01002720config OLPC_XO1_PM
2721 bool "OLPC XO-1 Power Management"
Borislav Petkovfa112cf2018-10-05 15:13:07 +02002722 depends on OLPC && MFD_CS5535=y && PM_SLEEP
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002723 ---help---
Daniel Drake97c4cb72011-06-25 17:34:11 +01002724 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002725
Daniel Drakecfee9592011-06-25 17:34:17 +01002726config OLPC_XO1_RTC
2727 bool "OLPC XO-1 Real Time Clock"
2728 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2729 ---help---
2730 Add support for the XO-1 real time clock, which can be used as a
2731 programmable wakeup source.
2732
Daniel Drake7feda8e2011-06-25 17:34:12 +01002733config OLPC_XO1_SCI
2734 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002735 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002736 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002737 select POWER_SUPPLY
Daniel Drake7feda8e2011-06-25 17:34:12 +01002738 ---help---
2739 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002740 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002741 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002742 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002743 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002744 - AC adapter status updates
2745 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002746
Daniel Drakea0f30f52011-06-25 17:34:18 +01002747config OLPC_XO15_SCI
2748 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002749 depends on OLPC && ACPI
2750 select POWER_SUPPLY
Daniel Drakea0f30f52011-06-25 17:34:18 +01002751 ---help---
2752 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2753 - EC-driven system wakeups
2754 - AC adapter status updates
2755 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002756
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002757config ALIX
2758 bool "PCEngines ALIX System Support (LED setup)"
2759 select GPIOLIB
2760 ---help---
2761 This option enables system support for the PCEngines ALIX.
2762 At present this just sets up LEDs for GPIO control on
2763 ALIX2/3/6 boards. However, other system specific setup should
2764 get added here.
2765
2766 Note: You must still enable the drivers for GPIO and LED support
2767 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2768
2769 Note: You have to set alix.force=1 for boards with Award BIOS.
2770
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002771config NET5501
2772 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2773 select GPIOLIB
2774 ---help---
2775 This option enables system support for the Soekris Engineering net5501.
2776
Philip A. Prindeville31970592012-01-14 01:45:39 -07002777config GEOS
2778 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2779 select GPIOLIB
2780 depends on DMI
2781 ---help---
2782 This option enables system support for the Traverse Technologies GEOS.
2783
Vivien Didelot7d029122013-01-04 16:18:14 -05002784config TS5500
2785 bool "Technologic Systems TS-5500 platform support"
2786 depends on MELAN
2787 select CHECK_SIGNATURE
2788 select NEW_LEDS
2789 select LEDS_CLASS
2790 ---help---
2791 This option enables system support for the Technologic Systems TS-5500.
2792
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002793endif # X86_32
2794
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002795config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002796 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002797 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002798
David Herrmanne3263ab2013-08-02 14:05:22 +02002799config X86_SYSFB
2800 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2801 help
2802 Firmwares often provide initial graphics framebuffers so the BIOS,
2803 bootloader or kernel can show basic video-output during boot for
2804 user-guidance and debugging. Historically, x86 used the VESA BIOS
2805 Extensions and EFI-framebuffers for this, which are mostly limited
2806 to x86.
2807 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2808 framebuffers so the new generic system-framebuffer drivers can be
2809 used on x86. If the framebuffer is not compatible with the generic
Nikolas Nybye3a5dc02018-08-25 19:10:54 -04002810 modes, it is advertised as fallback platform framebuffer so legacy
David Herrmanne3263ab2013-08-02 14:05:22 +02002811 drivers like efifb, vesafb and uvesafb can pick it up.
2812 If this option is not selected, all system framebuffers are always
2813 marked as fallback platform framebuffers as usual.
2814
2815 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2816 not be able to pick up generic system framebuffers if this option
2817 is selected. You are highly encouraged to enable simplefb as
2818 replacement if you select this option. simplefb can correctly deal
2819 with generic system framebuffers. But you should still keep vesafb
2820 and others enabled as fallback if a system framebuffer is
2821 incompatible with simplefb.
2822
2823 If unsure, say Y.
2824
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002825endmenu
2826
2827
Christoph Hellwig15724972018-07-31 13:39:30 +02002828menu "Binary Emulations"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002829
2830config IA32_EMULATION
2831 bool "IA32 Emulation"
2832 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002833 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002834 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002835 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002836 select COMPAT_OLD_SIGACTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002837 ---help---
H. J. Lu5fd92e62012-02-19 10:40:03 -08002838 Include code to run legacy 32-bit programs under a
2839 64-bit kernel. You should likely turn this on, unless you're
2840 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002841
2842config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002843 tristate "IA32 a.out support"
2844 depends on IA32_EMULATION
Borislav Petkoveac61652019-03-05 15:47:51 +01002845 depends on BROKEN
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002846 ---help---
2847 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002848
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002849config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002850 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002851 depends on X86_64
H. J. Lu5fd92e62012-02-19 10:40:03 -08002852 ---help---
2853 Include code to run binaries for the x32 native 32-bit ABI
2854 for 64-bit processors. An x32 process gets access to the
2855 full 64-bit register file and wide data path while leaving
2856 pointers at 32 bits for smaller memory footprint.
2857
2858 You will need a recent binutils (2.22 or later) with
2859 elf32_x86_64 support enabled to compile a kernel with this
2860 option set.
2861
Ingo Molnar953fee12016-11-15 10:22:52 +01002862config COMPAT_32
2863 def_bool y
2864 depends on IA32_EMULATION || X86_32
2865 select HAVE_UID16
2866 select OLD_SIGSUSPEND3
2867
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002868config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002869 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002870 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002871
Jan Beulich3120e252012-09-10 12:41:45 +01002872if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002873config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002874 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002875
2876config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002877 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002878 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002879endif
David Howellsee009e4a02011-03-07 15:06:20 +00002880
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002881endmenu
2882
2883
Keith Packarde5beae12008-11-03 18:21:45 +01002884config HAVE_ATOMIC_IOMAP
2885 def_bool y
2886 depends on X86_32
2887
Alessandro Rubini4692d772012-04-04 19:39:58 +02002888config X86_DEV_DMA_OPS
2889 bool
Alessandro Rubinif7219a52012-04-04 19:40:10 +02002890
Kirill A. Shutemove5855132017-06-06 14:31:20 +03002891config HAVE_GENERIC_GUP
2892 def_bool y
2893
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002894source "drivers/firmware/Kconfig"
2895
Avi Kivityedf88412007-12-16 11:02:48 +02002896source "arch/x86/kvm/Kconfig"