blob: 883da0abf7790c3ef8b01fe0e39688a4531cd5ac [file] [log] [blame]
Greg Kroah-Hartmanb2441312017-11-01 15:07:57 +01001# SPDX-License-Identifier: GPL-2.0
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01002# Select 32 or 64 bit
3config 64BIT
Masahiro Yamada104daea2018-05-28 18:21:40 +09004 bool "64-bit kernel" if "$(ARCH)" = "x86"
5 default "$(ARCH)" != "i386"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09006 help
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +01007 Say yes to build a 64-bit kernel - formerly known as x86_64
8 Say no to build a 32-bit kernel - formerly known as i386
9
10config X86_32
Jan Beulich3120e252012-09-10 12:41:45 +010011 def_bool y
12 depends on !64BIT
Ingo Molnar341c7872016-11-15 10:04:55 +010013 # Options that are inherently 32-bit kernel only:
14 select ARCH_WANT_IPC_PARSE_VERSION
15 select CLKSRC_I8253
16 select CLONE_BACKWARDS
Thomas Gleixner117ed452019-04-14 18:00:08 +020017 select HAVE_DEBUG_STACKOVERFLOW
Ingo Molnar341c7872016-11-15 10:04:55 +010018 select MODULES_USE_ELF_REL
19 select OLD_SIGACTION
Vincenzo Frascino7ac87072019-06-21 10:52:49 +010020 select GENERIC_VDSO_32
Sam Ravnborgdaa93fa2007-11-12 20:54:30 +010021
22config X86_64
Jan Beulich3120e252012-09-10 12:41:45 +010023 def_bool y
24 depends on 64BIT
Ingo Molnard94e0682016-11-15 10:11:57 +010025 # Options that are inherently 64-bit kernel only:
Alexandre Ghiti4eb07162019-05-13 17:19:04 -070026 select ARCH_HAS_GIGANTIC_PAGE
Ard Biesheuvelc12d3362019-11-08 13:22:27 +010027 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
Ingo Molnard94e0682016-11-15 10:11:57 +010028 select ARCH_USE_CMPXCHG_LOCKREF
29 select HAVE_ARCH_SOFT_DIRTY
30 select MODULES_USE_ELF_RELA
Christoph Hellwigf616ab52018-05-09 06:53:49 +020031 select NEED_DMA_MAP_STATE
Christoph Hellwig09230cb2018-04-24 09:00:54 +020032 select SWIOTLB
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
Thomas Gleixner2a21ad52018-09-17 14:45:35 +020059 select ARCH_CLOCKSOURCE_INIT
Ingo Molnarc763ea22016-11-15 10:26:39 +010060 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
Laura Abbottfa5b6ec2017-01-10 13:35:40 -080061 select ARCH_HAS_DEBUG_VIRTUAL
Anshuman Khandual399145f2020-06-04 16:47:15 -070062 select ARCH_HAS_DEBUG_VM_PGTABLE if !X86_PAE
Dan Williams21266be2015-11-19 18:19:29 -080063 select ARCH_HAS_DEVMEM_IS_ALLOWED
Douglas Andersonb1a57bb2020-05-07 13:08:42 -070064 select ARCH_HAS_EARLY_DEBUG if KGDB
Ingo Molnar6471b822015-06-03 10:00:13 +020065 select ARCH_HAS_ELF_RANDOMIZE
Linus Torvalds72d93102014-09-13 11:14:53 -070066 select ARCH_HAS_FAST_MULTIPLIER
Dave Hansen316d0972018-04-20 15:20:28 -070067 select ARCH_HAS_FILTER_PGPROT
Daniel Micay6974f0c2017-07-12 14:36:10 -070068 select ARCH_HAS_FORTIFY_SOURCE
Riku Voipio957e3fa2014-12-12 16:57:44 -080069 select ARCH_HAS_GCOV_PROFILE_ALL
Peter Zijlstra0f1441b2020-06-12 16:05:26 +020070 select ARCH_HAS_KCOV if X86_64 && STACK_VALIDATION
Thiago Jung Bauermann0c9c1d52019-08-06 01:49:14 -030071 select ARCH_HAS_MEM_ENCRYPT
Mathieu Desnoyers10bcc802018-01-29 15:20:18 -050072 select ARCH_HAS_MEMBARRIER_SYNC_CORE
Daniel Borkmann0ebeea82020-05-15 12:11:16 +020073 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
Ingo Molnarc763ea22016-11-15 10:26:39 +010074 select ARCH_HAS_PMEM_API if X86_64
Robin Murphy17596732019-07-16 16:30:47 -070075 select ARCH_HAS_PTE_DEVMAP if X86_64
Laurent Dufour3010a5e2018-06-07 17:06:08 -070076 select ARCH_HAS_PTE_SPECIAL
Dan Williams0aed55a2017-05-29 12:22:50 -070077 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
Dan Williams092b31a2018-07-08 13:46:17 -070078 select ARCH_HAS_UACCESS_MCSAFE if X86_64 && X86_MCE
Daniel Borkmannd2852a22017-02-21 16:09:33 +010079 select ARCH_HAS_SET_MEMORY
Rick Edgecombed253ca02019-04-25 17:11:34 -070080 select ARCH_HAS_SET_DIRECT_MAP
Laura Abbottad21fc42017-02-06 16:31:57 -080081 select ARCH_HAS_STRICT_KERNEL_RWX
82 select ARCH_HAS_STRICT_MODULE_RWX
Mathieu Desnoyersac1ab122018-01-29 15:20:16 -050083 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
Brian Gerst25c619e2020-03-13 15:51:42 -040084 select ARCH_HAS_SYSCALL_WRAPPER
Andrey Ryabininc6d30852016-01-20 15:00:55 -080085 select ARCH_HAS_UBSAN_SANITIZE_ALL
Zong Li7e01ccb2020-06-03 16:03:58 -070086 select ARCH_HAS_DEBUG_WX
Ingo Molnar6471b822015-06-03 10:00:13 +020087 select ARCH_HAVE_NMI_SAFE_CMPXCHG
88 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
Mark Salter77fbbc82013-10-07 22:18:07 -040089 select ARCH_MIGHT_HAVE_PC_PARPORT
Mark Salter5e2c18c2014-01-01 11:34:16 -080090 select ARCH_MIGHT_HAVE_PC_SERIO
Thomas Gleixner3599fe12019-04-25 11:45:22 +020091 select ARCH_STACKWALK
Arnd Bergmann2c870e62018-07-24 11:48:45 +020092 select ARCH_SUPPORTS_ACPI
Ingo Molnar6471b822015-06-03 10:00:13 +020093 select ARCH_SUPPORTS_ATOMIC_RMW
Ingo Molnar6471b822015-06-03 10:00:13 +020094 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
95 select ARCH_USE_BUILTIN_BSWAP
Ingo Molnar6471b822015-06-03 10:00:13 +020096 select ARCH_USE_QUEUED_RWLOCKS
97 select ARCH_USE_QUEUED_SPINLOCKS
Mark Brown2ce0d7f2020-04-16 19:24:02 +010098 select ARCH_USE_SYM_ANNOTATIONS
Andy Lutomirskice4a4e562017-05-28 10:00:14 -070099 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
Daniel Borkmann81c22042019-12-09 16:08:03 +0100100 select ARCH_WANT_DEFAULT_BPF_JIT if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100101 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
Alexandre Ghiti3876d4a2019-06-27 15:00:11 -0700102 select ARCH_WANT_HUGE_PMD_SHARE
Huang Ying38d8b4e2017-07-06 15:37:18 -0700103 select ARCH_WANTS_THP_SWAP if X86_64
Shile Zhang10916702019-12-04 08:46:31 +0800104 select BUILDTIME_TABLE_SORT
Ingo Molnar6471b822015-06-03 10:00:13 +0200105 select CLKEVT_I8253
Ingo Molnar6471b822015-06-03 10:00:13 +0200106 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
107 select CLOCKSOURCE_WATCHDOG
Ingo Molnar6471b822015-06-03 10:00:13 +0200108 select DCACHE_WORD_ACCESS
Linus Torvalds45471cd2015-06-24 19:52:06 -0700109 select EDAC_ATOMIC_SCRUB
110 select EDAC_SUPPORT
Ingo Molnar6471b822015-06-03 10:00:13 +0200111 select GENERIC_CLOCKEVENTS
112 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
113 select GENERIC_CLOCKEVENTS_MIN_ADJUST
114 select GENERIC_CMOS_UPDATE
115 select GENERIC_CPU_AUTOPROBE
Thomas Gleixner61dc0f52018-01-07 22:48:01 +0100116 select GENERIC_CPU_VULNERABILITIES
Ingo Molnar6471b822015-06-03 10:00:13 +0200117 select GENERIC_EARLY_IOREMAP
118 select GENERIC_FIND_FIRST_BIT
119 select GENERIC_IOMAP
Thomas Gleixnerc7d6c9d2017-06-20 01:37:46 +0200120 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
Thomas Gleixner0fa115d2017-09-13 23:29:38 +0200121 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
Thomas Gleixnerad7a9292017-06-20 01:37:33 +0200122 select GENERIC_IRQ_MIGRATION if SMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200123 select GENERIC_IRQ_PROBE
Thomas Gleixnerc201c912017-10-17 09:54:59 +0200124 select GENERIC_IRQ_RESERVATION_MODE
Ingo Molnar6471b822015-06-03 10:00:13 +0200125 select GENERIC_IRQ_SHOW
126 select GENERIC_PENDING_IRQ if SMP
Steven Price2ae27132020-02-03 17:36:24 -0800127 select GENERIC_PTDUMP
Ingo Molnar6471b822015-06-03 10:00:13 +0200128 select GENERIC_SMP_IDLE_THREAD
129 select GENERIC_STRNCPY_FROM_USER
130 select GENERIC_STRNLEN_USER
131 select GENERIC_TIME_VSYSCALL
Vincenzo Frascino7ac87072019-06-21 10:52:49 +0100132 select GENERIC_GETTIMEOFDAY
Dmitry Safonov550a77a2019-11-12 01:27:11 +0000133 select GENERIC_VDSO_TIME_NS
Christoph Hellwig39656e82019-07-11 20:56:49 -0700134 select GUP_GET_PTE_LOW_HIGH if X86_PAE
Hans de Goede17e58882020-01-23 22:02:42 +0100135 select HARDIRQS_SW_RESEND
Thomas Gleixner7edaeb62017-08-15 09:50:13 +0200136 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200137 select HAVE_ACPI_APEI if ACPI
138 select HAVE_ACPI_APEI_NMI if ACPI
139 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
Ingo Molnar6471b822015-06-03 10:00:13 +0200140 select HAVE_ARCH_AUDITSYSCALL
141 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
142 select HAVE_ARCH_JUMP_LABEL
Ard Biesheuvelb34006c2018-09-18 23:51:41 -0700143 select HAVE_ARCH_JUMP_LABEL_RELATIVE
Andrey Ryabinind17a1d92017-11-15 17:36:35 -0800144 select HAVE_ARCH_KASAN if X86_64
Daniel Axtens0609ae02019-11-30 17:55:00 -0800145 select HAVE_ARCH_KASAN_VMALLOC if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200146 select HAVE_ARCH_KGDB
Daniel Cashman9e08f572016-01-14 15:20:06 -0800147 select HAVE_ARCH_MMAP_RND_BITS if MMU
148 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
Dmitry Safonov1b028f72017-03-06 17:17:19 +0300149 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
Ard Biesheuvel271ca782018-08-21 21:56:00 -0700150 select HAVE_ARCH_PREL32_RELOCATIONS
Ingo Molnar6471b822015-06-03 10:00:13 +0200151 select HAVE_ARCH_SECCOMP_FILTER
Kees Cookf7d83c12017-08-16 13:26:03 -0700152 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
Alexander Popovafaef012018-08-17 01:16:58 +0300153 select HAVE_ARCH_STACKLEAK
Ingo Molnar6471b822015-06-03 10:00:13 +0200154 select HAVE_ARCH_TRACEHOOK
155 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
Matthew Wilcoxa00cc7d2017-02-24 14:57:02 -0800156 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
Peter Xub64d8d12020-04-20 18:13:45 -0700157 select HAVE_ARCH_USERFAULTFD_WP if X86_64 && USERFAULTFD
Andy Lutomirskie37e43a2016-08-11 02:35:23 -0700158 select HAVE_ARCH_VMAP_STACK if X86_64
Ingo Molnarc763ea22016-11-15 10:26:39 +0100159 select HAVE_ARCH_WITHIN_STACK_FRAMES
Masahiro Yamada2ff2b7e2019-08-19 14:54:20 +0900160 select HAVE_ASM_MODVERSIONS
Ingo Molnar6471b822015-06-03 10:00:13 +0200161 select HAVE_CMPXCHG_DOUBLE
162 select HAVE_CMPXCHG_LOCAL
163 select HAVE_CONTEXT_TRACKING if X86_64
Josh Triplettc1bd55f2015-06-30 15:00:00 -0700164 select HAVE_COPY_THREAD_TLS
Ingo Molnar6471b822015-06-03 10:00:13 +0200165 select HAVE_C_RECORDMCOUNT
166 select HAVE_DEBUG_KMEMLEAK
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700167 select HAVE_DMA_CONTIGUOUS
Steven Rostedt677aa9f2008-05-17 00:01:36 -0400168 select HAVE_DYNAMIC_FTRACE
Masami Hiramatsu06aeaae2012-09-28 17:15:17 +0900169 select HAVE_DYNAMIC_FTRACE_WITH_REGS
Steven Rostedt (VMware)562955f2019-11-08 13:11:39 -0500170 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
Wang YanQing03f57812018-05-03 14:10:43 +0800171 select HAVE_EBPF_JIT
Johannes Berg58340a02008-07-25 01:45:33 -0700172 select HAVE_EFFICIENT_UNALIGNED_ACCESS
Christoph Hellwig6630a8e2018-11-15 20:05:37 +0100173 select HAVE_EISA
Jiri Slaby5f56a5d2016-05-20 17:00:16 -0700174 select HAVE_EXIT_THREAD
Christoph Hellwig67a929e2019-07-11 20:57:14 -0700175 select HAVE_FAST_GUP
Steven Rostedt (VMware)644e0e82017-03-23 10:33:52 -0400176 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
Ingo Molnar6471b822015-06-03 10:00:13 +0200177 select HAVE_FTRACE_MCOUNT_RECORD
Ingo Molnar6471b822015-06-03 10:00:13 +0200178 select HAVE_FUNCTION_GRAPH_TRACER
179 select HAVE_FUNCTION_TRACER
Emese Revfy6b90bd42016-05-24 00:09:38 +0200180 select HAVE_GCC_PLUGINS
K.Prasad0067f122009-06-01 23:43:57 +0530181 select HAVE_HW_BREAKPOINT
Ingo Molnar6471b822015-06-03 10:00:13 +0200182 select HAVE_IDE
183 select HAVE_IOREMAP_PROT
Ingo Molnar6471b822015-06-03 10:00:13 +0200184 select HAVE_IRQ_TIME_ACCOUNTING
185 select HAVE_KERNEL_BZIP2
186 select HAVE_KERNEL_GZIP
187 select HAVE_KERNEL_LZ4
188 select HAVE_KERNEL_LZMA
189 select HAVE_KERNEL_LZO
190 select HAVE_KERNEL_XZ
191 select HAVE_KPROBES
192 select HAVE_KPROBES_ON_FTRACE
Masami Hiramatsu540adea2018-01-13 02:55:03 +0900193 select HAVE_FUNCTION_ERROR_INJECTION
Ingo Molnar6471b822015-06-03 10:00:13 +0200194 select HAVE_KRETPROBES
195 select HAVE_KVM
196 select HAVE_LIVEPATCH if X86_64
Frederic Weisbecker01027522010-04-11 18:55:56 +0200197 select HAVE_MIXED_BREAKPOINTS_REGS
Josh Poimboeufee9f8fc2017-07-24 18:36:57 -0500198 select HAVE_MOD_ARCH_SPECIFIC
Joel Fernandes (Google)9f132f72019-01-03 15:28:41 -0800199 select HAVE_MOVE_PMD
Petr Mladek42a0bb32016-05-20 17:00:33 -0700200 select HAVE_NMI
Ingo Molnar6471b822015-06-03 10:00:13 +0200201 select HAVE_OPROFILE
202 select HAVE_OPTPROBES
203 select HAVE_PCSPKR_PLATFORM
204 select HAVE_PERF_EVENTS
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200205 select HAVE_PERF_EVENTS_NMI
Nicholas Piggin92e5aae2017-08-18 15:15:51 -0700206 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
Christoph Hellwigeb01d422018-11-15 20:05:32 +0100207 select HAVE_PCI
Jiri Olsac5e63192012-08-07 15:20:36 +0200208 select HAVE_PERF_REGS
Jiri Olsac5ebced2012-08-07 15:20:40 +0200209 select HAVE_PERF_USER_STACK_DUMP
Peter Zijlstraff2e6d722020-02-03 17:37:02 -0800210 select MMU_GATHER_RCU_TABLE_FREE if PARAVIRT
Ingo Molnar6471b822015-06-03 10:00:13 +0200211 select HAVE_REGS_AND_STACK_ACCESS_API
Jiri Slaby6415b382018-05-18 08:47:13 +0200212 select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION
Masami Hiramatsu3c88ee194c2018-04-25 21:20:57 +0900213 select HAVE_FUNCTION_ARG_ACCESS_API
Masahiro Yamadad148eac2018-06-14 19:36:45 +0900214 select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
Ingo Molnarc763ea22016-11-15 10:26:39 +0100215 select HAVE_STACK_VALIDATION if X86_64
Mathieu Desnoyersd6761b82018-06-02 08:43:58 -0400216 select HAVE_RSEQ
Ingo Molnar6471b822015-06-03 10:00:13 +0200217 select HAVE_SYSCALL_TRACEPOINTS
Ingo Molnar6471b822015-06-03 10:00:13 +0200218 select HAVE_UNSTABLE_SCHED_CLOCK
Avi Kivity7c68af62009-09-19 09:40:22 +0300219 select HAVE_USER_RETURN_NOTIFIER
Vincenzo Frascino7ac87072019-06-21 10:52:49 +0100220 select HAVE_GENERIC_VDSO
Thomas Gleixner05736e42018-05-29 17:48:27 +0200221 select HOTPLUG_SMT if SMP
Thomas Gleixnerc01858082011-02-07 02:24:08 +0100222 select IRQ_FORCED_THREADING
Christoph Hellwig86596f02018-04-05 09:44:52 +0200223 select NEED_SG_DMA_LENGTH
Christoph Hellwig2eac9c22018-11-15 20:05:33 +0100224 select PCI_DOMAINS if PCI
Sinan Kaya625210c2019-01-21 23:19:58 +0000225 select PCI_LOCKLESS_CONFIG if PCI
Ingo Molnar6471b822015-06-03 10:00:13 +0200226 select PERF_EVENTS
Prarit Bhargava3195ef52013-02-14 12:02:54 -0500227 select RTC_LIB
Arnd Bergmannd6faca42016-06-01 16:46:23 +0200228 select RTC_MC146818_LIB
Ingo Molnar6471b822015-06-03 10:00:13 +0200229 select SPARSE_IRQ
Pranith Kumar83fe27e2014-12-05 11:24:45 -0500230 select SRCU
Ingo Molnar6471b822015-06-03 10:00:13 +0200231 select SYSCTL_EXCEPTION_TRACE
Andy Lutomirski15f4eae2016-09-13 14:29:25 -0700232 select THREAD_INFO_IN_TASK
Ingo Molnar6471b822015-06-03 10:00:13 +0200233 select USER_STACKTRACE_SUPPORT
234 select VIRT_TO_BUS
Ingo Molnar3b02a052020-04-13 09:44:39 +0200235 select HAVE_ARCH_KCSAN if X86_64
Ingo Molnar6471b822015-06-03 10:00:13 +0200236 select X86_FEATURE_NAMES if PROC_FS
Aubrey Li0c608da2019-06-06 09:22:35 +0800237 select PROC_PID_ARCH_STATUS if PROC_FS
Nayna Jain9e2b4be2020-03-08 20:57:51 -0400238 imply IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI
Balbir Singh7d8330a2008-02-10 12:46:28 +0530239
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200240config INSTRUCTION_DECODER
Jan Beulich3120e252012-09-10 12:41:45 +0100241 def_bool y
242 depends on KPROBES || PERF_EVENTS || UPROBES
Ingo Molnarba7e4d12009-06-06 13:58:12 +0200243
Linus Torvalds51b26ad2009-04-26 10:12:47 -0700244config OUTPUT_FORMAT
245 string
246 default "elf32-i386" if X86_32
247 default "elf64-x86-64" if X86_64
248
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100249config LOCKDEP_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100250 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100251
252config STACKTRACE_SUPPORT
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100253 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100254
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100255config MMU
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100256 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100257
Daniel Cashman9e08f572016-01-14 15:20:06 -0800258config ARCH_MMAP_RND_BITS_MIN
259 default 28 if 64BIT
260 default 8
261
262config ARCH_MMAP_RND_BITS_MAX
263 default 32 if 64BIT
264 default 16
265
266config ARCH_MMAP_RND_COMPAT_BITS_MIN
267 default 8
268
269config ARCH_MMAP_RND_COMPAT_BITS_MAX
270 default 16
271
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100272config SBUS
273 bool
274
275config GENERIC_ISA_DMA
Jan Beulich3120e252012-09-10 12:41:45 +0100276 def_bool y
277 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100278
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100279config GENERIC_BUG
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100280 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100281 depends on BUG
Jan Beulichb93a5312008-12-16 11:40:27 +0000282 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
283
284config GENERIC_BUG_RELATIVE_POINTERS
285 bool
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100286
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100287config ARCH_MAY_HAVE_PC_FDC
Jan Beulich3120e252012-09-10 12:41:45 +0100288 def_bool y
289 depends on ISA_DMA_API
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100290
Sam Ravnborg1032c0b2007-11-06 21:35:08 +0100291config GENERIC_CALIBRATE_DELAY
292 def_bool y
293
venkatesh.pallipadi@intel.com9a0b8412008-01-31 17:35:06 -0800294config ARCH_HAS_CPU_RELAX
295 def_bool y
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100296
Pekka Enberg1b27d052008-04-28 02:12:22 -0700297config ARCH_HAS_CACHE_LINE_SIZE
298 def_bool y
299
Dave Hansen316d0972018-04-20 15:20:28 -0700300config ARCH_HAS_FILTER_PGPROT
301 def_bool y
302
Mike Travisdd5af902008-01-30 13:33:32 +0100303config HAVE_SETUP_PER_CPU_AREA
Brian Gerst89c9c4c2009-01-27 12:56:48 +0900304 def_bool y
travis@sgi.comb32ef632008-01-30 13:32:51 +0100305
Tejun Heo08fc4582009-08-14 15:00:49 +0900306config NEED_PER_CPU_EMBED_FIRST_CHUNK
307 def_bool y
308
309config NEED_PER_CPU_PAGE_FIRST_CHUNK
Tejun Heo11124412009-02-20 16:29:09 +0900310 def_bool y
311
Johannes Berg801e4062007-12-08 02:12:39 +0100312config ARCH_HIBERNATION_POSSIBLE
313 def_bool y
Johannes Berg801e4062007-12-08 02:12:39 +0100314
Johannes Bergf4cb5702007-12-08 02:14:00 +0100315config ARCH_SUSPEND_POSSIBLE
316 def_bool y
Johannes Bergf4cb5702007-12-08 02:14:00 +0100317
Steve Capper53313b22013-04-30 08:03:42 +0100318config ARCH_WANT_GENERAL_HUGETLB
319 def_bool y
320
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100321config ZONE_DMA32
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000322 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100323
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100324config AUDIT_ARCH
Jan Beuliche0fd24a2015-02-05 15:39:34 +0000325 def_bool y if X86_64
Sam Ravnborg8d5fffb2007-11-06 23:30:30 +0100326
Akinobu Mita6a11f752009-03-31 15:23:17 -0700327config ARCH_SUPPORTS_DEBUG_PAGEALLOC
328 def_bool y
329
Andrey Ryabinind6f2d752015-07-02 12:09:38 +0300330config KASAN_SHADOW_OFFSET
331 hex
332 depends on KASAN
333 default 0xdffffc0000000000
334
Shane Wang69575d32009-09-01 18:25:07 -0700335config HAVE_INTEL_TXT
336 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -0700337 depends on INTEL_IOMMU && ACPI
Shane Wang69575d32009-09-01 18:25:07 -0700338
Sam Ravnborg6b0c3d42008-01-30 13:32:27 +0100339config X86_32_SMP
340 def_bool y
341 depends on X86_32 && SMP
342
343config X86_64_SMP
344 def_bool y
345 depends on X86_64 && SMP
346
Tejun Heoccbeed32009-02-09 22:17:40 +0900347config X86_32_LAZY_GS
348 def_bool y
Masahiro Yamada8458f8c2018-06-14 19:36:43 +0900349 depends on X86_32 && !STACKPROTECTOR
Tejun Heoccbeed32009-02-09 22:17:40 +0900350
Srikar Dronamraju2b144492012-02-09 14:56:42 +0530351config ARCH_SUPPORTS_UPROBES
352 def_bool y
353
Rob Herringd20642f2014-04-18 17:19:54 -0500354config FIX_EARLYCON_MEM
355 def_bool y
356
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +0300357config DYNAMIC_PHYSICAL_MASK
358 bool
359
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700360config PGTABLE_LEVELS
361 int
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +0300362 default 5 if X86_5LEVEL
Kirill A. Shutemov98233362015-04-14 15:46:14 -0700363 default 4 if X86_64
364 default 3 if X86_PAE
365 default 2
366
Masahiro Yamada2a61f472018-05-28 18:22:00 +0900367config CC_HAS_SANE_STACKPROTECTOR
368 bool
369 default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
370 default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
371 help
372 We have to make sure stack protector is unconditionally disabled if
373 the compiler produces broken code.
374
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100375menu "Processor type and features"
376
Randy Dunlap5ee71532012-01-16 11:57:18 -0800377config ZONE_DMA
378 bool "DMA memory allocation support" if EXPERT
379 default y
380 help
381 DMA memory allocation support allows devices with less than 32-bit
382 addressing to allocate within the first 16MB of address space.
383 Disable if no such devices will be used.
384
385 If unsure, say Y.
386
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100387config SMP
388 bool "Symmetric multi-processing support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900389 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100390 This enables support for systems with more than one CPU. If you have
Robert Graffham4a474152014-01-23 15:55:29 -0800391 a system with only one CPU, say N. If you have a system with more
392 than one CPU, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100393
Robert Graffham4a474152014-01-23 15:55:29 -0800394 If you say N here, the kernel will run on uni- and multiprocessor
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100395 machines, but will use only one CPU of a multiprocessor machine. If
396 you say Y here, the kernel will run on many, but not all,
Robert Graffham4a474152014-01-23 15:55:29 -0800397 uniprocessor machines. On a uniprocessor machine, the kernel
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100398 will run faster if you say N here.
399
400 Note that if you say Y here and choose architecture "586" or
401 "Pentium" under "Processor family", the kernel will not work on 486
402 architectures. Similarly, multiprocessor kernels for the "PPro"
403 architecture may not work on all Pentium based boards.
404
405 People using multiprocessor machines who say Y here should also say
406 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
407 Management" code will be disabled if you say Y here.
408
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -0300409 See also <file:Documentation/x86/i386/IO-APIC.rst>,
Mauro Carvalho Chehab4f4cfa62019-06-27 14:56:51 -0300410 <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100411 <http://www.tldp.org/docs.html#howto>.
412
413 If you don't know what to do here, say N.
414
Josh Triplett9def39be2013-10-30 08:09:45 -0700415config X86_FEATURE_NAMES
416 bool "Processor feature human-readable names" if EMBEDDED
417 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900418 help
Josh Triplett9def39be2013-10-30 08:09:45 -0700419 This option compiles in a table of x86 feature bits and corresponding
420 names. This is required to support /proc/cpuinfo and a few kernel
421 messages. You can disable this to save space, at the expense of
422 making those few kernel messages show numeric feature bits instead.
423
424 If in doubt, say Y.
425
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800426config X86_X2APIC
427 bool "Support x2apic"
Jan Kiszka19e3d602015-05-04 17:58:01 +0200428 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900429 help
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800430 This enables x2apic support on CPUs that have this feature.
431
432 This allows 32-bit apic IDs (so it can support very large systems),
433 and accesses the local apic via MSRs not via mmio.
434
Yinghai Lu06cd9a72009-02-16 17:29:58 -0800435 If you don't know what to do here, say N.
436
Yinghai Lu6695c852008-06-19 12:13:09 -0700437config X86_MPPARSE
Bin Gao6e87f9b72012-10-25 09:35:44 -0700438 bool "Enable MPS table" if ACPI || SFI
Jan Beulich7a527682008-10-30 10:38:24 +0000439 default y
Ingo Molnar5ab74722008-07-10 14:42:03 +0200440 depends on X86_LOCAL_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900441 help
Yinghai Lu6695c852008-06-19 12:13:09 -0700442 For old smp systems that do not have proper acpi support. Newer systems
443 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
Yinghai Lu6695c852008-06-19 12:13:09 -0700444
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000445config GOLDFISH
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +0100446 def_bool y
447 depends on X86_GOLDFISH
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000448
David Woodhouse76b04382018-01-11 21:46:25 +0000449config RETPOLINE
450 bool "Avoid speculative indirect branches in kernel"
451 default y
Peter Zijlstrad5028ba2018-02-06 09:46:13 +0100452 select STACK_VALIDATION if HAVE_STACK_VALIDATION
David Woodhouse76b04382018-01-11 21:46:25 +0000453 help
454 Compile kernel with the retpoline compiler options to guard against
455 kernel-to-user data leaks by avoiding speculative indirect
456 branches. Requires a compiler with -mindirect-branch=thunk-extern
457 support for full protection. The kernel may run slower.
458
Johannes Weinere6d42932019-01-29 17:44:36 -0500459config X86_CPU_RESCTRL
460 bool "x86 CPU resource control support"
Babu Moger6fe07ce2018-11-21 20:28:39 +0000461 depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
Thomas Gleixner59fe5a72016-11-15 15:17:12 +0100462 select KERNFS
Chen Yue79f15a2020-01-15 17:28:51 +0800463 select PROC_CPU_RESCTRL if PROC_FS
Fenghua Yu78e99b42016-10-22 06:19:53 -0700464 help
Johannes Weinere6d42932019-01-29 17:44:36 -0500465 Enable x86 CPU resource control support.
Babu Moger6fe07ce2018-11-21 20:28:39 +0000466
467 Provide support for the allocation and monitoring of system resources
468 usage by the CPU.
469
470 Intel calls this Intel Resource Director Technology
471 (Intel(R) RDT). More information about RDT can be found in the
472 Intel x86 Architecture Software Developer Manual.
473
474 AMD calls this AMD Platform Quality of Service (AMD QoS).
475 More information about AMD QoS can be found in the AMD64 Technology
476 Platform Quality of Service Extensions manual.
Fenghua Yu78e99b42016-10-22 06:19:53 -0700477
478 Say N if unsure.
479
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800480if X86_32
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800481config X86_BIGSMP
482 bool "Support for big SMP systems with more than 8 CPUs"
483 depends on SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900484 help
Randy Dunlape133f6e2019-12-03 16:06:47 -0800485 This option is needed for the systems that have more than 8 CPUs.
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800486
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800487config X86_EXTENDED_PLATFORM
488 bool "Support for extended (non-PC) x86 platforms"
489 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900490 help
Ingo Molnar06ac8342009-01-27 18:11:43 +0100491 If you disable this option then the kernel will only support
492 standard PC platforms. (which covers the vast majority of
493 systems out there.)
494
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800495 If you enable this option then you'll be able to select support
496 for the following (non-PC) 32 bit x86 platforms:
Ben Hutchingscb7b8022013-06-24 01:05:25 +0100497 Goldfish (Android emulator)
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800498 AMD Elan
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800499 RDC R-321x SoC
500 SGI 320/540 (Visual Workstation)
Alessandro Rubini83125a32012-04-04 19:40:21 +0200501 STA2X11-based (e.g. Northville)
Thomas Gleixner3f4110a2009-08-29 14:54:20 +0200502 Moorestown MID devices
Ingo Molnar06ac8342009-01-27 18:11:43 +0100503
504 If you have one of these systems, or if you want to build a
505 generic distribution kernel, say Y here - otherwise say N.
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800506endif
Ingo Molnar06ac8342009-01-27 18:11:43 +0100507
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800508if X86_64
509config X86_EXTENDED_PLATFORM
510 bool "Support for extended (non-PC) x86 platforms"
511 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900512 help
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800513 If you disable this option then the kernel will only support
514 standard PC platforms. (which covers the vast majority of
515 systems out there.)
516
517 If you enable this option then you'll be able to select support
518 for the following (non-PC) 64 bit x86 platforms:
Steffen Persvold44b111b52011-12-06 00:07:26 +0800519 Numascale NumaChip
Ravikiran G Thirumalai84250912009-02-20 16:59:11 -0800520 ScaleMP vSMP
521 SGI Ultraviolet
522
523 If you have one of these systems, or if you want to build a
524 generic distribution kernel, say Y here - otherwise say N.
525endif
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800526# This is an alphabetically sorted list of 64 bit extended platforms
527# Please maintain the alphabetic order if and when there are additions
Steffen Persvold44b111b52011-12-06 00:07:26 +0800528config X86_NUMACHIP
529 bool "Numascale NumaChip"
530 depends on X86_64
531 depends on X86_EXTENDED_PLATFORM
532 depends on NUMA
533 depends on SMP
534 depends on X86_X2APIC
Daniel J Bluemanf9726bf2012-12-07 14:24:32 -0700535 depends on PCI_MMCONFIG
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900536 help
Steffen Persvold44b111b52011-12-06 00:07:26 +0800537 Adds support for Numascale NumaChip large-SMP systems. Needed to
538 enable more than ~168 cores.
539 If you don't have one of these, you should say N here.
Nick Piggin03b48632009-01-20 04:36:04 +0100540
Ingo Molnar6a485652009-01-27 18:29:13 +0100541config X86_VSMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800542 bool "ScaleMP vSMP"
Borislav Petkov6276a072013-03-04 21:20:21 +0100543 select HYPERVISOR_GUEST
Ingo Molnar6a485652009-01-27 18:29:13 +0100544 select PARAVIRT
545 depends on X86_64 && PCI
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800546 depends on X86_EXTENDED_PLATFORM
Shai Fultheimead91d42012-04-16 10:39:35 +0300547 depends on SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900548 help
Ingo Molnar6a485652009-01-27 18:29:13 +0100549 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
550 supposed to run on these EM64T-based machines. Only choose this option
551 if you have one of these machines.
552
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800553config X86_UV
554 bool "SGI Ultraviolet"
555 depends on X86_64
556 depends on X86_EXTENDED_PLATFORM
Jack Steiner54c28d22009-04-03 15:39:42 -0500557 depends on NUMA
Andrew Morton1ecb4ae2016-02-11 16:13:20 -0800558 depends on EFI
Suresh Siddha9d6c26e2009-04-20 13:02:31 -0700559 depends on X86_X2APIC
Ingo Molnar1222e562015-05-06 06:23:59 +0200560 depends on PCI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900561 help
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800562 This option is needed in order to support SGI Ultraviolet systems.
563 If you don't have one of these, you should say N here.
564
565# Following is an alphabetically sorted list of 32 bit extended platforms
566# Please maintain the alphabetic order if and when there are additions
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100567
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000568config X86_GOLDFISH
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +0100569 bool "Goldfish (Virtual Platform)"
570 depends on X86_EXTENDED_PLATFORM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900571 help
Jun Nakajimaddd70cf2013-01-21 17:23:09 +0000572 Enable support for the Goldfish virtual platform used primarily
573 for Android development. Unless you are building for the Android
574 Goldfish emulator say N here.
575
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800576config X86_INTEL_CE
577 bool "CE4100 TV platform"
578 depends on PCI
579 depends on PCI_GODIRECT
Jiang Liu6084a6e2014-06-09 16:19:46 +0800580 depends on X86_IO_APIC
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800581 depends on X86_32
582 depends on X86_EXTENDED_PLATFORM
Dirk Brandewie37bc9f52010-11-09 12:08:08 -0800583 select X86_REBOOTFIXUPS
Sebastian Andrzej Siewiorda6b7372011-02-22 21:07:37 +0100584 select OF
585 select OF_EARLY_FLATTREE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900586 help
Thomas Gleixnerc751e172010-11-09 12:08:04 -0800587 Select for the Intel CE media processor (CE4100) SOC.
588 This option compiles in support for the CE4100 SOC for settop
589 boxes and media devices.
590
David Cohen4cb9b002013-12-16 17:37:26 -0800591config X86_INTEL_MID
Alan Cox43605ef2011-07-12 17:49:29 +0100592 bool "Intel MID platform support"
Alan Cox43605ef2011-07-12 17:49:29 +0100593 depends on X86_EXTENDED_PLATFORM
David Cohenedc6bc72014-01-21 10:41:39 -0800594 depends on X86_PLATFORM_DEVICES
Alan Cox1ea7c672011-11-10 13:29:14 +0000595 depends on PCI
Andy Shevchenko3fda5bb2016-01-15 22:11:07 +0200596 depends on X86_64 || (PCI_GOANY && X86_32)
Alan Cox1ea7c672011-11-10 13:29:14 +0000597 depends on X86_IO_APIC
Alan Cox7c9c3a12011-12-29 14:43:16 +0000598 select SFI
David Cohen4cb9b002013-12-16 17:37:26 -0800599 select I2C
Alan Cox7c9c3a12011-12-29 14:43:16 +0000600 select DW_APB_TIMER
Alan Cox1ea7c672011-11-10 13:29:14 +0000601 select APB_TIMER
Mika Westerberg54b34aa2020-04-16 11:15:33 +0300602 select INTEL_SCU_PCI
Mika Westerberg15a713d2012-01-26 17:35:05 +0000603 select MFD_INTEL_MSIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900604 help
David Cohen4cb9b002013-12-16 17:37:26 -0800605 Select to build a kernel capable of supporting Intel MID (Mobile
606 Internet Device) platform systems which do not have the PCI legacy
607 interfaces. If you are building for a PC class system say N here.
Alan Cox1ea7c672011-11-10 13:29:14 +0000608
David Cohen4cb9b002013-12-16 17:37:26 -0800609 Intel MID platforms are based on an Intel processor and chipset which
610 consume less power than most of the x86 derivatives.
Alan Cox43605ef2011-07-12 17:49:29 +0100611
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000612config X86_INTEL_QUARK
613 bool "Intel Quark platform support"
614 depends on X86_32
615 depends on X86_EXTENDED_PLATFORM
616 depends on X86_PLATFORM_DEVICES
617 depends on X86_TSC
618 depends on PCI
619 depends on PCI_GOANY
620 depends on X86_IO_APIC
621 select IOSF_MBI
622 select INTEL_IMR
Andy Shevchenko9ab6eb52015-03-05 17:24:04 +0200623 select COMMON_CLK
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900624 help
Bryan O'Donoghue8bbc2a12015-01-30 16:29:39 +0000625 Select to include support for Quark X1000 SoC.
626 Say Y here if you have a Quark based system such as the Arduino
627 compatible Intel Galileo.
628
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000629config X86_INTEL_LPSS
630 bool "Intel Low Power Subsystem Support"
Sinan Kaya5962dd22019-01-02 18:10:37 +0000631 depends on X86 && ACPI && PCI
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000632 select COMMON_CLK
Mathias Nyman0f531432013-09-13 17:02:29 +0300633 select PINCTRL
Andy Shevchenkoeebb3e82015-12-12 02:45:06 +0100634 select IOSF_MBI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900635 help
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000636 Select to build support for Intel Low Power Subsystem such as
637 found on Intel Lynxpoint PCH. Selecting this option enables
Mathias Nyman0f531432013-09-13 17:02:29 +0300638 things like clock tree (common clock framework) and pincontrol
639 which are needed by the LPSS peripheral drivers.
Mika Westerberg3d48aab2013-01-18 13:45:59 +0000640
Ken Xue92082a82015-02-06 08:27:51 +0800641config X86_AMD_PLATFORM_DEVICE
642 bool "AMD ACPI2Platform devices support"
643 depends on ACPI
644 select COMMON_CLK
645 select PINCTRL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900646 help
Ken Xue92082a82015-02-06 08:27:51 +0800647 Select to interpret AMD specific ACPI device to platform device
648 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
649 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
650 implemented under PINCTRL subsystem.
651
David E. Boxced3ce72014-09-17 22:13:50 -0700652config IOSF_MBI
653 tristate "Intel SoC IOSF Sideband support for SoC platforms"
654 depends on PCI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900655 help
David E. Boxced3ce72014-09-17 22:13:50 -0700656 This option enables sideband register access support for Intel SoC
657 platforms. On these platforms the IOSF sideband is used in lieu of
658 MSR's for some register accesses, mostly but not limited to thermal
659 and power. Drivers may query the availability of this device to
660 determine if they need the sideband in order to work on these
661 platforms. The sideband is available on the following SoC products.
662 This list is not meant to be exclusive.
663 - BayTrail
664 - Braswell
665 - Quark
666
667 You should say Y if you are running a kernel on one of these SoC's.
668
David E. Boxed2226b2014-09-17 22:13:51 -0700669config IOSF_MBI_DEBUG
670 bool "Enable IOSF sideband access through debugfs"
671 depends on IOSF_MBI && DEBUG_FS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900672 help
David E. Boxed2226b2014-09-17 22:13:51 -0700673 Select this option to expose the IOSF sideband access registers (MCR,
674 MDR, MCRX) through debugfs to write and read register information from
675 different units on the SoC. This is most useful for obtaining device
676 state information for debug and analysis. As this is a general access
677 mechanism, users of this option would have specific knowledge of the
678 device they want to access.
679
680 If you don't require the option or are in doubt, say N.
681
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800682config X86_RDC321X
683 bool "RDC R-321x SoC"
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100684 depends on X86_32
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800685 depends on X86_EXTENDED_PLATFORM
686 select M486
687 select X86_REBOOTFIXUPS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900688 help
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800689 This option is needed for RDC R-321x system-on-chip, also known
690 as R-8610-(G).
691 If you don't have one of these chips, you should say N here.
692
Ingo Molnare0c7ae32009-01-27 18:43:09 +0100693config X86_32_NON_STANDARD
Ingo Molnar9c398012009-01-27 18:24:57 +0100694 bool "Support non-standard 32-bit SMP architectures"
695 depends on X86_32 && SMP
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800696 depends on X86_EXTENDED_PLATFORM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900697 help
H. Peter Anvinb5660ba2014-02-25 12:14:06 -0800698 This option compiles in the bigsmp and STA2X11 default
699 subarchitectures. It is intended for a generic binary
700 kernel. If you select them all, kernel will probe it one by
701 one and will fallback to default.
Yinghai Lud49c4282008-06-08 18:31:54 -0700702
Ravikiran G Thirumalaic5c606d2009-02-09 18:18:14 -0800703# Alphabetically sorted list of Non standard 32 bit platforms
Yinghai Lud49c4282008-06-08 18:31:54 -0700704
Linus Torvaldsd949f362009-09-26 09:35:07 -0700705config X86_SUPPORTS_MEMORY_FAILURE
Jan Beulich6fc108a2010-04-21 15:23:44 +0100706 def_bool y
Linus Torvaldsd949f362009-09-26 09:35:07 -0700707 # MCE code calls memory_failure():
708 depends on X86_MCE
709 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
Linus Torvaldsd949f362009-09-26 09:35:07 -0700710 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
711 depends on X86_64 || !SPARSEMEM
712 select ARCH_SUPPORTS_MEMORY_FAILURE
Linus Torvaldsd949f362009-09-26 09:35:07 -0700713
Alessandro Rubini83125a32012-04-04 19:40:21 +0200714config STA2X11
715 bool "STA2X11 Companion Chip Support"
716 depends on X86_32_NON_STANDARD && PCI
Alessandro Rubini83125a32012-04-04 19:40:21 +0200717 select SWIOTLB
718 select MFD_STA2X11
Linus Walleij01450712016-06-02 14:20:18 +0200719 select GPIOLIB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900720 help
Alessandro Rubini83125a32012-04-04 19:40:21 +0200721 This adds support for boards based on the STA2X11 IO-Hub,
722 a.k.a. "ConneXt". The chip is used in place of the standard
723 PC chipset, so all "standard" peripherals are missing. If this
724 option is selected the kernel will still be able to boot on
725 standard PC machines.
726
Shérab82148d12010-09-25 06:06:57 +0200727config X86_32_IRIS
728 tristate "Eurobraille/Iris poweroff module"
729 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900730 help
Shérab82148d12010-09-25 06:06:57 +0200731 The Iris machines from EuroBraille do not have APM or ACPI support
732 to shut themselves down properly. A special I/O sequence is
733 needed to do so, which is what this module does at
734 kernel shutdown.
735
736 This is only for Iris machines from EuroBraille.
737
738 If unused, say N.
739
Ingo Molnarae1e9132008-11-11 09:05:16 +0100740config SCHED_OMIT_FRAME_POINTER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100741 def_bool y
742 prompt "Single-depth WCHAN output"
Ken Chena87d0912008-11-06 11:10:49 -0800743 depends on X86
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900744 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100745 Calculate simpler /proc/<PID>/wchan values. If this option
746 is disabled then wchan values will recurse back to the
747 caller function. This provides more accurate wchan values,
748 at the expense of slightly more scheduling overhead.
749
750 If in doubt, say "Y".
751
Borislav Petkov6276a072013-03-04 21:20:21 +0100752menuconfig HYPERVISOR_GUEST
753 bool "Linux guest support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900754 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100755 Say Y here to enable options for running Linux under various hyper-
756 visors. This option enables basic hypervisor detection and platform
757 setup.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100758
Borislav Petkov6276a072013-03-04 21:20:21 +0100759 If you say N, all options in this submenu will be skipped and
760 disabled, and Linux guest support won't be built in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100761
Borislav Petkov6276a072013-03-04 21:20:21 +0100762if HYPERVISOR_GUEST
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100763
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100764config PARAVIRT
765 bool "Enable paravirtualization code"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900766 help
Eduardo Pereira Habkoste61bd942008-01-30 13:33:32 +0100767 This changes the kernel so it can modify itself when it is run
768 under a hypervisor, potentially improving performance significantly
769 over full virtualization. However, when run without a hypervisor
770 the kernel is theoretically slower and slightly larger.
771
Juergen Grossc00a2802018-08-28 09:40:21 +0200772config PARAVIRT_XXL
773 bool
774
Borislav Petkov6276a072013-03-04 21:20:21 +0100775config PARAVIRT_DEBUG
776 bool "paravirt-ops debugging"
777 depends on PARAVIRT && DEBUG_KERNEL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900778 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100779 Enable to debug paravirt_ops internals. Specifically, BUG if
780 a paravirt_op is missing when it is called.
781
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700782config PARAVIRT_SPINLOCKS
783 bool "Paravirtualization layer for spinlocks"
Kees Cook6ea30382012-10-02 11:16:47 -0700784 depends on PARAVIRT && SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900785 help
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700786 Paravirtualized spinlocks allow a pvops backend to replace the
787 spinlock implementation with something virtualization-friendly
788 (for example, block the virtual CPU rather than spinning).
789
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530790 It has a minimal impact on native kernels and gives a nice performance
791 benefit on paravirtualized KVM / Xen kernels.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700792
Raghavendra K T4c4e4f62013-10-21 21:35:08 +0530793 If you are unsure how to answer this question, answer Y.
Jeremy Fitzhardingeb4ecc122009-05-13 17:16:55 -0700794
Zhao Yakuiecca25022019-04-30 11:45:23 +0800795config X86_HV_CALLBACK_VECTOR
796 def_bool n
797
Borislav Petkov6276a072013-03-04 21:20:21 +0100798source "arch/x86/xen/Kconfig"
799
800config KVM_GUEST
801 bool "KVM Guest support (including kvmclock)"
802 depends on PARAVIRT
803 select PARAVIRT_CLOCK
Marcelo Tosattia1c44232019-07-03 20:51:29 -0300804 select ARCH_CPUIDLE_HALTPOLL
Borislav Petkov6276a072013-03-04 21:20:21 +0100805 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900806 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100807 This option enables various optimizations for running under the KVM
808 hypervisor. It includes a paravirtualized clock, so that instead
809 of relying on a PIT (or probably other) emulation by the
810 underlying device model, the host provides the guest with
811 timing infrastructure such as time of day, and system time
812
Marcelo Tosattia1c44232019-07-03 20:51:29 -0300813config ARCH_CPUIDLE_HALTPOLL
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +0100814 def_bool n
815 prompt "Disable host haltpoll when loading haltpoll driver"
816 help
Marcelo Tosattia1c44232019-07-03 20:51:29 -0300817 If virtualized under KVM, disable host haltpoll.
818
Maran Wilson77336072018-12-10 11:07:28 -0800819config PVH
820 bool "Support for running PVH guests"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900821 help
Maran Wilson77336072018-12-10 11:07:28 -0800822 This option enables the PVH entry point for guest virtual machines
823 as specified in the x86/HVM direct boot ABI.
824
Borislav Petkov6276a072013-03-04 21:20:21 +0100825config PARAVIRT_TIME_ACCOUNTING
826 bool "Paravirtual steal time accounting"
827 depends on PARAVIRT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900828 help
Borislav Petkov6276a072013-03-04 21:20:21 +0100829 Select this option to enable fine granularity task steal time
830 accounting. Time spent executing other tasks in parallel with
831 the current vCPU is discounted from the vCPU power. To account for
832 that, there can be a small performance impact.
833
834 If in doubt, say N here.
835
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200836config PARAVIRT_CLOCK
837 bool
Gerd Hoffmann7af192c2008-06-03 16:17:29 +0200838
Jan Kiszka4a362602017-11-27 09:11:46 +0100839config JAILHOUSE_GUEST
840 bool "Jailhouse non-root cell support"
Arnd Bergmannabde5872018-01-15 16:51:20 +0100841 depends on X86_64 && PCI
Jan Kiszka87e65d02017-11-27 09:11:48 +0100842 select X86_PM_TIMER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900843 help
Jan Kiszka4a362602017-11-27 09:11:46 +0100844 This option allows to run Linux as guest in a Jailhouse non-root
845 cell. You can leave this option disabled if you only want to start
846 Jailhouse and run Linux afterwards in the root cell.
847
Zhao Yakuiec7972c2019-04-30 11:45:24 +0800848config ACRN_GUEST
849 bool "ACRN Guest support"
850 depends on X86_64
Zhao Yakui498ad392019-04-30 11:45:25 +0800851 select X86_HV_CALLBACK_VECTOR
Zhao Yakuiec7972c2019-04-30 11:45:24 +0800852 help
853 This option allows to run Linux as guest in the ACRN hypervisor. ACRN is
854 a flexible, lightweight reference open-source hypervisor, built with
855 real-time and safety-criticality in mind. It is built for embedded
856 IOT with small footprint and real-time features. More details can be
857 found in https://projectacrn.org/.
858
Borislav Petkov6276a072013-03-04 21:20:21 +0100859endif #HYPERVISOR_GUEST
Jeremy Fitzhardinge97349132008-06-25 00:19:14 -0400860
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100861source "arch/x86/Kconfig.cpu"
862
863config HPET_TIMER
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100864 def_bool X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100865 prompt "HPET Timer Support" if X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900866 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100867 Use the IA-PC HPET (High Precision Event Timer) to manage
868 time in preference to the PIT and RTC, if a HPET is
869 present.
870 HPET is the next generation timer replacing legacy 8254s.
871 The HPET provides a stable time base on SMP
872 systems, unlike the TSC, but it is more expensive to access,
Michael S. Tsirkin4e7f9df2016-02-11 01:05:01 +0200873 as it is off-chip. The interface used is documented
874 in the HPET spec, revision 1.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100875
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100876 You can safely choose Y here. However, HPET will only be
877 activated if the platform and the BIOS support this feature.
878 Otherwise the 8254 will be used for timing services.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100879
Ingo Molnar8f9ca472009-02-05 16:21:53 +0100880 Choose N to continue using the legacy 8254 timer.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100881
882config HPET_EMULATE_RTC
Harvey Harrison3c2362e2008-01-30 13:31:03 +0100883 def_bool y
Bernhard Walle9d8af782008-02-06 01:38:52 -0800884 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100885
Jacob Panbb24c472009-09-02 07:37:17 -0700886config APB_TIMER
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +0100887 def_bool y if X86_INTEL_MID
888 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
889 select DW_APB_TIMER
890 depends on X86_INTEL_MID && SFI
891 help
892 APB timer is the replacement for 8254, HPET on X86 MID platforms.
893 The APBT provides a stable time base on SMP
894 systems, unlike the TSC, but it is more expensive to access,
895 as it is off-chip. APB timers are always running regardless of CPU
896 C states, they are used as per CPU clockevent device when possible.
Jacob Panbb24c472009-09-02 07:37:17 -0700897
David Rientjes6a108a12011-01-20 14:44:16 -0800898# Mark as expert because too many people got it wrong.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100899# The code disables itself when not needed.
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700900config DMI
901 default y
Ard Biesheuvelcf074402014-01-23 15:54:39 -0800902 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
David Rientjes6a108a12011-01-20 14:44:16 -0800903 bool "Enable DMI scanning" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900904 help
Thomas Petazzoni7ae93922008-04-28 02:14:14 -0700905 Enabled scanning of DMI to identify machine quirks. Say Y
906 here unless you have verified that your setup is not
907 affected by entries in the DMI blacklist. Required by PNP
908 BIOS code.
909
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100910config GART_IOMMU
Andi Kleen38901f12013-10-04 14:37:56 -0700911 bool "Old AMD GART IOMMU support"
Christoph Hellwiga4ce5a42018-04-03 15:47:59 +0200912 select IOMMU_HELPER
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100913 select SWIOTLB
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +0200914 depends on X86_64 && PCI && AMD_NB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900915 help
Ingo Molnarced3c422013-10-06 11:45:20 +0200916 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
917 GART based hardware IOMMUs.
918
919 The GART supports full DMA access for devices with 32-bit access
920 limitations, on systems with more than 3 GB. This is usually needed
921 for USB, sound, many IDE/SATA chipsets and some other devices.
922
923 Newer systems typically have a modern AMD IOMMU, supported via
924 the CONFIG_AMD_IOMMU=y config option.
925
926 In normal configurations this driver is only active when needed:
927 there's more than 3 GB of memory and the system contains a
928 32-bit limited device.
929
930 If unsure, say Y.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100931
Mike Travis1184dc22008-05-12 21:21:12 +0200932config MAXSMP
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200933 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
Kees Cook6ea30382012-10-02 11:16:47 -0700934 depends on X86_64 && SMP && DEBUG_KERNEL
Mike Travis36f51012008-12-16 17:33:51 -0800935 select CPUMASK_OFFSTACK
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900936 help
Samuel Thibaultddb0c5a2010-08-21 21:32:41 +0200937 Enable maximum number of CPUS and NUMA Nodes for this architecture.
Mike Travis1184dc22008-05-12 21:21:12 +0200938 If unsure, say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100939
Ingo Molnaraec64872018-02-10 12:36:29 +0100940#
941# The maximum number of CPUs supported:
942#
943# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
944# and which can be configured interactively in the
945# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
946#
947# The ranges are different on 32-bit and 64-bit kernels, depending on
948# hardware capabilities and scalability features of the kernel.
949#
950# ( If MAXSMP is enabled we just use the highest possible value and disable
951# interactive configuration. )
952#
953
954config NR_CPUS_RANGE_BEGIN
955 int
956 default NR_CPUS_RANGE_END if MAXSMP
957 default 1 if !SMP
958 default 2
959
960config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800961 int
962 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100963 default 64 if SMP && X86_BIGSMP
964 default 8 if SMP && !X86_BIGSMP
965 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800966
Ingo Molnaraec64872018-02-10 12:36:29 +0100967config NR_CPUS_RANGE_END
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800968 int
969 depends on X86_64
Scott Wood1edae1a2019-10-12 02:00:54 -0500970 default 8192 if SMP && CPUMASK_OFFSTACK
971 default 512 if SMP && !CPUMASK_OFFSTACK
Ingo Molnaraec64872018-02-10 12:36:29 +0100972 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800973
Ingo Molnaraec64872018-02-10 12:36:29 +0100974config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800975 int
976 depends on X86_32
Ingo Molnaraec64872018-02-10 12:36:29 +0100977 default 32 if X86_BIGSMP
978 default 8 if SMP
979 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800980
Ingo Molnaraec64872018-02-10 12:36:29 +0100981config NR_CPUS_DEFAULT
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800982 int
983 depends on X86_64
Ingo Molnaraec64872018-02-10 12:36:29 +0100984 default 8192 if MAXSMP
985 default 64 if SMP
986 default 1 if !SMP
Randy Dunlapa0d0bb42018-02-09 16:51:03 -0800987
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100988config NR_CPUS
Mike Travis36f51012008-12-16 17:33:51 -0800989 int "Maximum number of CPUs" if SMP && !MAXSMP
Ingo Molnaraec64872018-02-10 12:36:29 +0100990 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
991 default NR_CPUS_DEFAULT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +0900992 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100993 This allows you to specify the maximum number of CPUs which this
Josh Boyerbb61ccc2013-11-05 09:37:29 -0500994 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
Kirill A. Shutemovcad14bb2015-05-08 13:25:26 +0300995 supported value is 8192, otherwise the maximum value is 512. The
Sam Ravnborg506f1d072007-11-09 21:56:54 +0100996 minimum value which makes sense is 2.
997
Ingo Molnaraec64872018-02-10 12:36:29 +0100998 This is purely to save memory: each supported CPU adds about 8KB
999 to the kernel image.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001000
1001config SCHED_SMT
Thomas Gleixnerdbe73362018-11-25 19:33:37 +01001002 def_bool y if SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001003
1004config SCHED_MC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001005 def_bool y
1006 prompt "Multi-core scheduler support"
Borislav Petkovc8e56d22015-06-04 18:55:25 +02001007 depends on SMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001008 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001009 Multi-core scheduler support improves the CPU scheduler's decision
1010 making when dealing with multi-core CPU chips at a cost of slightly
1011 increased overhead in some places. If unsure say N here.
1012
Tim Chende966cf2016-11-29 10:43:27 -08001013config SCHED_MC_PRIO
1014 bool "CPU core priorities scheduler support"
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001015 depends on SCHED_MC && CPU_SUP_INTEL
1016 select X86_INTEL_PSTATE
1017 select CPU_FREQ
Tim Chende966cf2016-11-29 10:43:27 -08001018 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001019 help
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001020 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1021 core ordering determined at manufacturing time, which allows
1022 certain cores to reach higher turbo frequencies (when running
1023 single threaded workloads) than others.
Tim Chende966cf2016-11-29 10:43:27 -08001024
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001025 Enabling this kernel feature teaches the scheduler about
1026 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1027 scheduler's CPU selection logic accordingly, so that higher
1028 overall system performance can be achieved.
Tim Chende966cf2016-11-29 10:43:27 -08001029
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001030 This feature will have no effect on CPUs without this feature.
Tim Chende966cf2016-11-29 10:43:27 -08001031
Ingo Molnar0a21fc12016-11-30 08:33:54 +01001032 If unsure say Y here.
Tim Chen5e76b2a2016-11-22 12:23:55 -08001033
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001034config UP_LATE_INIT
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001035 def_bool y
1036 depends on !SMP && X86_LOCAL_APIC
Thomas Gleixner30b8b002015-01-15 21:22:39 +00001037
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001038config X86_UP_APIC
Jan Beulich50849ee2015-02-05 15:31:56 +00001039 bool "Local APIC support on uniprocessors" if !PCI_MSI
1040 default PCI_MSI
Bryan O'Donoghue38a1dfd2015-01-22 22:58:49 +00001041 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001042 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001043 A local APIC (Advanced Programmable Interrupt Controller) is an
1044 integrated interrupt controller in the CPU. If you have a single-CPU
1045 system which has a processor with a local APIC, you can say Y here to
1046 enable and use it. If you say Y here even though your machine doesn't
1047 have a local APIC, then the kernel will still run with no slowdown at
1048 all. The local APIC supports CPU-generated self-interrupts (timer,
1049 performance counters), and the NMI watchdog which detects hard
1050 lockups.
1051
1052config X86_UP_IOAPIC
1053 bool "IO-APIC support on uniprocessors"
1054 depends on X86_UP_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001055 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001056 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1057 SMP-capable replacement for PC-style interrupt controllers. Most
1058 SMP systems and many recent uniprocessor systems have one.
1059
1060 If you have a single-CPU system with an IO-APIC, you can say Y here
1061 to use it. If you say Y here even though your machine doesn't have
1062 an IO-APIC, then the kernel will still run with no slowdown at all.
1063
1064config X86_LOCAL_APIC
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001065 def_bool y
Thomas Petazzoni0dbc6072013-10-03 11:59:14 +02001066 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
Jiang Liub5dc8e62015-04-13 14:11:24 +08001067 select IRQ_DOMAIN_HIERARCHY
Jiang Liu52f518a2015-04-13 14:11:35 +08001068 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001069
1070config X86_IO_APIC
Jan Beulichb1da1e72015-02-05 15:35:21 +00001071 def_bool y
1072 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001073
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001074config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1075 bool "Reroute for broken boot IRQs"
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001076 depends on X86_IO_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001077 help
Stefan Assmann41b9eb22008-07-15 13:48:55 +02001078 This option enables a workaround that fixes a source of
1079 spurious interrupts. This is recommended when threaded
1080 interrupt handling is used on systems where the generation of
1081 superfluous "boot interrupts" cannot be disabled.
1082
1083 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1084 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1085 kernel does during interrupt handling). On chipsets where this
1086 boot IRQ generation cannot be disabled, this workaround keeps
1087 the original IRQ line masked so that only the equivalent "boot
1088 IRQ" is delivered to the CPUs. The workaround also tells the
1089 kernel to set up the IRQ handler on the boot IRQ line. In this
1090 way only one interrupt is delivered to the kernel. Otherwise
1091 the spurious second interrupt may cause the kernel to bring
1092 down (vital) interrupt lines.
1093
1094 Only affects "broken" chipsets. Interrupt sharing may be
1095 increased on these systems.
1096
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001097config X86_MCE
Andi Kleenbab9bc62009-07-09 00:31:38 +02001098 bool "Machine Check / overheating reporting"
Chen, Gong648ed942015-08-12 18:29:34 +02001099 select GENERIC_ALLOCATOR
Borislav Petkove57dbaf2011-09-13 15:23:21 +02001100 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001101 help
Andi Kleenbab9bc62009-07-09 00:31:38 +02001102 Machine Check support allows the processor to notify the
1103 kernel if it detects a problem (e.g. overheating, data corruption).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001104 The action the kernel takes depends on the severity of the problem,
Andi Kleenbab9bc62009-07-09 00:31:38 +02001105 ranging from warning messages to halting the machine.
Andi Kleen4efc0672009-04-28 19:07:31 +02001106
Tony Luck5de97c92017-03-27 11:33:03 +02001107config X86_MCELOG_LEGACY
1108 bool "Support for deprecated /dev/mcelog character device"
1109 depends on X86_MCE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001110 help
Tony Luck5de97c92017-03-27 11:33:03 +02001111 Enable support for /dev/mcelog which is needed by the old mcelog
1112 userspace logging daemon. Consider switching to the new generation
1113 rasdaemon solution.
1114
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001115config X86_MCE_INTEL
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001116 def_bool y
1117 prompt "Intel MCE features"
Andi Kleenc1ebf832009-07-09 00:31:41 +02001118 depends on X86_MCE && X86_LOCAL_APIC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001119 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001120 Additional support for intel specific MCE features such as
1121 the thermal monitor.
1122
1123config X86_MCE_AMD
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001124 def_bool y
1125 prompt "AMD MCE features"
Yazen Ghannamf5382de2016-11-17 17:57:27 -05001126 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001127 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001128 Additional support for AMD specific MCE features such as
1129 the DRAM Error Threshold.
1130
Andi Kleen4efc0672009-04-28 19:07:31 +02001131config X86_ANCIENT_MCE
Jan Beulich6fc108a2010-04-21 15:23:44 +01001132 bool "Support for old Pentium 5 / WinChip machine checks"
Andi Kleenc31d9632009-07-09 00:31:37 +02001133 depends on X86_32 && X86_MCE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001134 help
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001135 Include support for machine check handling on old Pentium 5 or WinChip
Masanari Iida5065a702013-11-30 21:38:43 +09001136 systems. These typically need to be enabled explicitly on the command
Hidetoshi Setocd13adcc2009-05-27 16:57:31 +09001137 line.
Andi Kleen4efc0672009-04-28 19:07:31 +02001138
Andi Kleenb2762682009-02-12 13:49:31 +01001139config X86_MCE_THRESHOLD
1140 depends on X86_MCE_AMD || X86_MCE_INTEL
Jan Beulich6fc108a2010-04-21 15:23:44 +01001141 def_bool y
Andi Kleenb2762682009-02-12 13:49:31 +01001142
Andi Kleenea149b32009-04-29 19:31:00 +02001143config X86_MCE_INJECT
Borislav Petkovbc8e80d2017-06-13 18:28:30 +02001144 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
Andi Kleenea149b32009-04-29 19:31:00 +02001145 tristate "Machine check injector support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001146 help
Andi Kleenea149b32009-04-29 19:31:00 +02001147 Provide support for injecting machine checks for testing purposes.
1148 If you don't know what a machine check is and you don't do kernel
1149 QA it is safe to say n.
1150
Andi Kleen4efc0672009-04-28 19:07:31 +02001151config X86_THERMAL_VECTOR
1152 def_bool y
Andi Kleen5bb38ad2009-07-09 00:31:39 +02001153 depends on X86_MCE_INTEL
Andi Kleen4efc0672009-04-28 19:07:31 +02001154
Peter Zijlstra07dc9002016-03-29 14:30:35 +02001155source "arch/x86/events/Kconfig"
Kan Liange633c652016-03-20 01:33:36 -07001156
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001157config X86_LEGACY_VM86
Ingo Molnar1e642812015-09-05 08:58:10 +02001158 bool "Legacy VM86 support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001159 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001160 help
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001161 This option allows user programs to put the CPU into V8086
1162 mode, which is an 80286-era approximation of 16-bit real mode.
1163
1164 Some very old versions of X and/or vbetool require this option
1165 for user mode setting. Similarly, DOSEMU will use it if
1166 available to accelerate real mode DOS programs. However, any
1167 recent version of DOSEMU, X, or vbetool should be fully
1168 functional even without kernel VM86 support, as they will all
Ingo Molnar1e642812015-09-05 08:58:10 +02001169 fall back to software emulation. Nevertheless, if you are using
1170 a 16-bit DOS program where 16-bit performance matters, vm86
1171 mode might be faster than emulation and you might want to
1172 enable this option.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001173
Ingo Molnar1e642812015-09-05 08:58:10 +02001174 Note that any app that works on a 64-bit kernel is unlikely to
1175 need this option, as 64-bit kernels don't, and can't, support
1176 V8086 mode. This option is also unrelated to 16-bit protected
1177 mode and is not needed to run most 16-bit programs under Wine.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001178
Ingo Molnar1e642812015-09-05 08:58:10 +02001179 Enabling this option increases the complexity of the kernel
1180 and slows down exception handling a tiny bit.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001181
Ingo Molnar1e642812015-09-05 08:58:10 +02001182 If unsure, say N here.
Andy Lutomirski5aef51c2015-07-10 08:34:23 -07001183
1184config VM86
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001185 bool
1186 default X86_LEGACY_VM86
H. Peter Anvin34273f42014-05-04 10:36:22 -07001187
1188config X86_16BIT
1189 bool "Enable support for 16-bit segments" if EXPERT
1190 default y
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001191 depends on MODIFY_LDT_SYSCALL
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001192 help
H. Peter Anvin34273f42014-05-04 10:36:22 -07001193 This option is required by programs like Wine to run 16-bit
1194 protected mode legacy code on x86 processors. Disabling
1195 this option saves about 300 bytes on i386, or around 6K text
1196 plus 16K runtime memory on x86-64,
1197
1198config X86_ESPFIX32
1199 def_bool y
1200 depends on X86_16BIT && X86_32
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001201
H. Peter Anvin197725d2014-05-04 10:00:49 -07001202config X86_ESPFIX64
1203 def_bool y
H. Peter Anvin34273f42014-05-04 10:36:22 -07001204 depends on X86_16BIT && X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001205
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001206config X86_VSYSCALL_EMULATION
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001207 bool "Enable vsyscall emulation" if EXPERT
1208 default y
1209 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001210 help
Andy Lutomirski1ad83c82014-10-29 14:33:47 -07001211 This enables emulation of the legacy vsyscall page. Disabling
1212 it is roughly equivalent to booting with vsyscall=none, except
1213 that it will also disable the helpful warning if a program
1214 tries to use a vsyscall. With this option set to N, offending
1215 programs will just segfault, citing addresses of the form
1216 0xffffffffff600?00.
1217
1218 This option is required by many programs built before 2013, and
1219 care should be used even with newer programs if set to N.
1220
1221 Disabling this option saves about 7K of kernel size and
1222 possibly 4K of additional runtime pagetable memory.
1223
Thomas Gleixner111e7b12019-11-12 21:40:33 +01001224config X86_IOPL_IOPERM
1225 bool "IOPERM and IOPL Emulation"
Thomas Gleixnera24ca992019-11-11 23:03:29 +01001226 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001227 help
Thomas Gleixner111e7b12019-11-12 21:40:33 +01001228 This enables the ioperm() and iopl() syscalls which are necessary
1229 for legacy applications.
1230
Thomas Gleixnerc8137ac2019-11-11 23:03:28 +01001231 Legacy IOPL support is an overbroad mechanism which allows user
1232 space aside of accessing all 65536 I/O ports also to disable
1233 interrupts. To gain this access the caller needs CAP_SYS_RAWIO
1234 capabilities and permission from potentially active security
1235 modules.
1236
1237 The emulation restricts the functionality of the syscall to
1238 only allowing the full range I/O port access, but prevents the
Thomas Gleixnera24ca992019-11-11 23:03:29 +01001239 ability to disable interrupts from user space which would be
1240 granted if the hardware IOPL mechanism would be used.
Thomas Gleixnerc8137ac2019-11-11 23:03:28 +01001241
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001242config TOSHIBA
1243 tristate "Toshiba Laptop support"
1244 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001245 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001246 This adds a driver to safely access the System Management Mode of
1247 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1248 not work on models with a Phoenix BIOS. The System Management Mode
1249 is used to set the BIOS and power saving options on Toshiba portables.
1250
1251 For information on utilities to make use of this driver see the
1252 Toshiba Linux utilities web site at:
1253 <http://www.buzzard.org.uk/toshiba/>.
1254
1255 Say Y if you intend to run this kernel on a Toshiba portable.
1256 Say N otherwise.
1257
1258config I8K
Pali Rohár039ae582015-05-14 13:16:37 +02001259 tristate "Dell i8k legacy laptop support"
Jean Delvare949a9d72011-05-25 20:43:33 +02001260 select HWMON
Pali Rohár039ae582015-05-14 13:16:37 +02001261 select SENSORS_DELL_SMM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001262 help
Pali Rohár039ae582015-05-14 13:16:37 +02001263 This option enables legacy /proc/i8k userspace interface in hwmon
1264 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1265 temperature and allows controlling fan speeds of Dell laptops via
1266 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1267 it reports also power and hotkey status. For fan speed control is
1268 needed userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001269
Pali Rohár039ae582015-05-14 13:16:37 +02001270 Say Y if you intend to run this kernel on old Dell laptops or want to
1271 use userspace package i8kutils.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001272 Say N otherwise.
1273
1274config X86_REBOOTFIXUPS
Jan Beulich9ba16082008-10-15 22:01:38 -07001275 bool "Enable X86 board specific fixups for reboot"
1276 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001277 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001278 This enables chipset and/or board specific fixups to be done
1279 in order to get reboot to work correctly. This is only needed on
1280 some combinations of hardware and BIOS. The symptom, for which
1281 this config is intended, is when reboot ends with a stalled/hung
1282 system.
1283
1284 Currently, the only fixup is for the Geode machines using
Florian Fainelli5e3a77e2008-01-30 13:33:36 +01001285 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001286
1287 Say Y if you want to enable the fixup. Currently, it's safe to
1288 enable this option even if you don't need it.
1289 Say N otherwise.
1290
1291config MICROCODE
Borislav Petkov9a2bc332015-10-20 11:54:44 +02001292 bool "CPU microcode loading support"
1293 default y
Borislav Petkov80030e32013-10-13 18:36:29 +02001294 depends on CPU_SUP_AMD || CPU_SUP_INTEL
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001295 select FW_LOADER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001296 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001297 If you say Y here, you will be able to update the microcode on
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001298 Intel and AMD processors. The Intel support is for the IA32 family,
1299 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1300 AMD support is for families 0x10 and later. You will obviously need
1301 the actual microcode binary data itself which is not shipped with
1302 the Linux kernel.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001303
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001304 The preferred method to load microcode from a detached initrd is described
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001305 in Documentation/x86/microcode.rst. For that you need to enable
Borislav Petkov5f9c01a2016-02-03 12:33:29 +01001306 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1307 initrd for microcode blobs.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001308
Benjamin Gilbertc508c462018-01-23 18:06:32 -08001309 In addition, you can build the microcode into the kernel. For that you
1310 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1311 config option.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001312
Peter Oruba8d86f392008-07-28 18:44:21 +02001313config MICROCODE_INTEL
Borislav Petkove43f6e62012-08-01 19:17:01 +02001314 bool "Intel microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001315 depends on MICROCODE
1316 default MICROCODE
1317 select FW_LOADER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001318 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001319 This options enables microcode patch loading support for Intel
1320 processors.
Peter Oruba8d86f392008-07-28 18:44:21 +02001321
Alanb8989db2014-01-20 18:01:56 +00001322 For the current Intel microcode data package go to
1323 <https://downloadcenter.intel.com> and search for
1324 'Linux Processor Microcode Data File'.
Peter Oruba8d86f392008-07-28 18:44:21 +02001325
Peter Oruba80cc9f12008-07-28 18:44:22 +02001326config MICROCODE_AMD
Borislav Petkove43f6e62012-08-01 19:17:01 +02001327 bool "AMD microcode loading support"
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001328 depends on MICROCODE
1329 select FW_LOADER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001330 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001331 If you select this option, microcode patch loading support for AMD
1332 processors will be enabled.
Peter Oruba80cc9f12008-07-28 18:44:22 +02001333
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001334config MICROCODE_OLD_INTERFACE
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001335 bool "Ancient loading interface (DEPRECATED)"
1336 default n
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001337 depends on MICROCODE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001338 help
Borislav Petkovc02f48e2019-04-05 06:28:11 +02001339 DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface
1340 which was used by userspace tools like iucode_tool and microcode.ctl.
1341 It is inadequate because it runs too late to be able to properly
1342 load microcode on a machine and it needs special tools. Instead, you
1343 should've switched to the early loading method with the initrd or
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001344 builtin microcode by now: Documentation/x86/microcode.rst
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001345
1346config X86_MSR
1347 tristate "/dev/cpu/*/msr - Model-specific register support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001348 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001349 This device gives privileged processes access to the x86
1350 Model-Specific Registers (MSRs). It is a character device with
1351 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1352 MSR accesses are directed to a specific CPU on multi-processor
1353 systems.
1354
1355config X86_CPUID
1356 tristate "/dev/cpu/*/cpuid - CPU information support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001357 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001358 This device gives processes access to the x86 CPUID instruction to
1359 be executed on a specific processor. It is a character device
1360 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1361 /dev/cpu/31/cpuid.
1362
1363choice
1364 prompt "High Memory Support"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001365 default HIGHMEM4G
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001366 depends on X86_32
1367
1368config NOHIGHMEM
1369 bool "off"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001370 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001371 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1372 However, the address space of 32-bit x86 processors is only 4
1373 Gigabytes large. That means that, if you have a large amount of
1374 physical memory, not all of it can be "permanently mapped" by the
1375 kernel. The physical memory that's not permanently mapped is called
1376 "high memory".
1377
1378 If you are compiling a kernel which will never run on a machine with
1379 more than 1 Gigabyte total physical RAM, answer "off" here (default
1380 choice and suitable for most users). This will result in a "3GB/1GB"
1381 split: 3GB are mapped so that each process sees a 3GB virtual memory
1382 space and the remaining part of the 4GB virtual memory space is used
1383 by the kernel to permanently map as much physical memory as
1384 possible.
1385
1386 If the machine has between 1 and 4 Gigabytes physical RAM, then
1387 answer "4GB" here.
1388
1389 If more than 4 Gigabytes is used then answer "64GB" here. This
1390 selection turns Intel PAE (Physical Address Extension) mode on.
1391 PAE implements 3-level paging on IA32 processors. PAE is fully
1392 supported by Linux, PAE mode is implemented on all recent Intel
1393 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1394 then the kernel will not boot on CPUs that don't support PAE!
1395
1396 The actual amount of total physical memory will either be
1397 auto detected or can be forced by using a kernel command line option
1398 such as "mem=256M". (Try "man bootparam" or see the documentation of
1399 your boot loader (lilo or loadlin) about how to pass options to the
1400 kernel at boot time.)
1401
1402 If unsure, say "off".
1403
1404config HIGHMEM4G
1405 bool "4GB"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001406 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001407 Select this if you have a 32-bit processor and between 1 and 4
1408 gigabytes of physical RAM.
1409
1410config HIGHMEM64G
1411 bool "64GB"
Matthew Whitehead69b8d3f2018-02-15 11:54:55 -05001412 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001413 select X86_PAE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001414 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001415 Select this if you have a 32-bit processor and more than 4
1416 gigabytes of physical RAM.
1417
1418endchoice
1419
1420choice
David Rientjes6a108a12011-01-20 14:44:16 -08001421 prompt "Memory split" if EXPERT
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001422 default VMSPLIT_3G
1423 depends on X86_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001424 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001425 Select the desired split between kernel and user memory.
1426
1427 If the address range available to the kernel is less than the
1428 physical memory installed, the remaining memory will be available
1429 as "high memory". Accessing high memory is a little more costly
1430 than low memory, as it needs to be mapped into the kernel first.
1431 Note that increasing the kernel address space limits the range
1432 available to user programs, making the address space there
1433 tighter. Selecting anything other than the default 3G/1G split
1434 will also likely make your kernel incompatible with binary-only
1435 kernel modules.
1436
1437 If you are not absolutely sure what you are doing, leave this
1438 option alone!
1439
1440 config VMSPLIT_3G
1441 bool "3G/1G user/kernel split"
1442 config VMSPLIT_3G_OPT
1443 depends on !X86_PAE
1444 bool "3G/1G user/kernel split (for full 1G low memory)"
1445 config VMSPLIT_2G
1446 bool "2G/2G user/kernel split"
1447 config VMSPLIT_2G_OPT
1448 depends on !X86_PAE
1449 bool "2G/2G user/kernel split (for full 2G low memory)"
1450 config VMSPLIT_1G
1451 bool "1G/3G user/kernel split"
1452endchoice
1453
1454config PAGE_OFFSET
1455 hex
1456 default 0xB0000000 if VMSPLIT_3G_OPT
1457 default 0x80000000 if VMSPLIT_2G
1458 default 0x78000000 if VMSPLIT_2G_OPT
1459 default 0x40000000 if VMSPLIT_1G
1460 default 0xC0000000
1461 depends on X86_32
1462
1463config HIGHMEM
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001464 def_bool y
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001465 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001466
1467config X86_PAE
Jan Beulich9ba16082008-10-15 22:01:38 -07001468 bool "PAE (Physical Address Extension) Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001469 depends on X86_32 && !HIGHMEM4G
Christoph Hellwigd4a451d2018-04-03 16:24:20 +02001470 select PHYS_ADDR_T_64BIT
Christian Melki9d99c712015-10-05 17:31:33 +02001471 select SWIOTLB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001472 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001473 PAE is required for NX support, and furthermore enables
1474 larger swapspace support for non-overcommit purposes. It
1475 has the cost of more pagetable lookup overhead, and also
1476 consumes more pagetable space per process.
1477
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001478config X86_5LEVEL
1479 bool "Enable 5-level page tables support"
Kirill A. Shutemov18ec1ea2019-09-13 12:54:52 +03001480 default y
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03001481 select DYNAMIC_MEMORY_LAYOUT
Kirill A. Shutemov162434e2018-02-14 14:16:54 +03001482 select SPARSEMEM_VMEMMAP
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001483 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001484 help
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001485 5-level paging enables access to larger address space:
1486 upto 128 PiB of virtual address space and 4 PiB of
1487 physical address space.
1488
1489 It will be supported by future Intel CPUs.
1490
Kirill A. Shutemov6657fca2018-02-14 21:25:42 +03001491 A kernel with the option enabled can be booted on machines that
1492 support 4- or 5-level paging.
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001493
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001494 See Documentation/x86/x86_64/5level-paging.rst for more
Kirill A. Shutemov77ef56e2017-07-17 01:59:54 +03001495 information.
1496
1497 Say N if unsure.
1498
Ingo Molnar10971ab2015-03-05 08:18:23 +01001499config X86_DIRECT_GBPAGES
Luis R. Rodrigueze5008ab2015-03-04 17:24:12 -08001500 def_bool y
Vlastimil Babka2e1da132019-08-07 15:02:58 +02001501 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001502 help
Ingo Molnar10971ab2015-03-05 08:18:23 +01001503 Certain kernel features effectively disable kernel
1504 linear 1 GB mappings (even if the CPU otherwise
1505 supports them), so don't confuse the user by printing
1506 that we have them enabled.
Nick Piggin9e899812008-10-22 12:33:16 +02001507
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001508config X86_CPA_STATISTICS
1509 bool "Enable statistic for Change Page Attribute"
1510 depends on DEBUG_FS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001511 help
Ingo Molnarb75baaf2019-11-20 15:57:04 +01001512 Expose statistics about the Change Page Attribute mechanism, which
Colin Ian Kinga9432452019-04-16 11:57:51 +01001513 helps to determine the effectiveness of preserving large and huge
Thomas Gleixner5c280cf2018-09-17 16:29:12 +02001514 page mappings when mapping protections are changed.
1515
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001516config AMD_MEM_ENCRYPT
1517 bool "AMD Secure Memory Encryption (SME) support"
1518 depends on X86_64 && CPU_SUP_AMD
David Rientjes82fef0a2020-04-14 17:05:01 -07001519 select DMA_COHERENT_POOL
Kirill A. Shutemov94d49eb2018-05-18 14:30:28 +03001520 select DYNAMIC_PHYSICAL_MASK
Ard Biesheuvelce9084b2019-02-02 10:41:17 +01001521 select ARCH_USE_MEMREMAP_PROT
Tom Lendacky9087c372019-07-10 19:01:19 +00001522 select ARCH_HAS_FORCE_DMA_UNENCRYPTED
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001523 help
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001524 Say yes to enable support for the encryption of system memory.
1525 This requires an AMD processor that supports Secure Memory
1526 Encryption (SME).
1527
1528config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1529 bool "Activate AMD Secure Memory Encryption (SME) by default"
1530 default y
1531 depends on AMD_MEM_ENCRYPT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001532 help
Tom Lendacky7744ccd2017-07-17 16:10:03 -05001533 Say yes to have system memory encrypted by default if running on
1534 an AMD processor that supports Secure Memory Encryption (SME).
1535
1536 If set to Y, then the encryption of system memory can be
1537 deactivated with the mem_encrypt=off command line option.
1538
1539 If set to N, then the encryption of system memory can be
1540 activated with the mem_encrypt=on command line option.
1541
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001542# Common NUMA Features
1543config NUMA
Randy Dunlape133f6e2019-12-03 16:06:47 -08001544 bool "NUMA Memory Allocation and Scheduler Support"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001545 depends on SMP
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001546 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1547 default y if X86_BIGSMP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001548 help
Randy Dunlape133f6e2019-12-03 16:06:47 -08001549 Enable NUMA (Non-Uniform Memory Access) support.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001550
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001551 The kernel will try to allocate memory used by a CPU on the
1552 local memory controller of the CPU and add some more
1553 NUMA awareness to the kernel.
1554
Ingo Molnarc280ea52008-11-08 13:29:45 +01001555 For 64-bit this is recommended if the system is Intel Core i7
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001556 (or later), AMD Opteron, or EM64T NUMA.
1557
H. Peter Anvinb5660ba2014-02-25 12:14:06 -08001558 For 32-bit this is only needed if you boot a 32-bit
David Rientjes7cf6c942014-02-11 18:11:13 -08001559 kernel on a 64-bit NUMA platform.
KOSAKI Motohirofd51b2d2008-11-05 02:27:19 +09001560
1561 Otherwise, you should say N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001562
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001563config AMD_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001564 def_bool y
1565 prompt "Old style AMD Opteron NUMA detection"
Tejun Heo5da0ef92011-07-11 10:34:32 +02001566 depends on X86_64 && NUMA && PCI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001567 help
Hans Rosenfeldeec1d4f2010-10-29 17:14:30 +02001568 Enable AMD NUMA node topology detection. You should say Y here if
1569 you have a multi processor AMD system. This uses an old method to
1570 read the NUMA configuration directly from the builtin Northbridge
1571 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1572 which also takes priority if both are compiled in.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001573
1574config X86_64_ACPI_NUMA
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001575 def_bool y
1576 prompt "ACPI NUMA detection"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001577 depends on X86_64 && NUMA && ACPI && PCI
1578 select ACPI_NUMA
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001579 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001580 Enable ACPI SRAT based node topology detection.
1581
1582config NUMA_EMU
1583 bool "NUMA emulation"
Tejun Heo1b7e03e2011-05-02 17:24:48 +02001584 depends on NUMA
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001585 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001586 Enable NUMA emulation. A flat machine will be split
1587 into virtual nodes when booted with "numa=fake=N", where N is the
1588 number of nodes. This is only useful for debugging.
1589
1590config NODES_SHIFT
Linus Torvaldsd25e26b2008-08-25 14:15:38 -07001591 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
David Rientjes51591e32010-03-25 15:39:27 -07001592 range 1 10
1593 default "10" if MAXSMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001594 default "6" if X86_64
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001595 default "3"
1596 depends on NEED_MULTIPLE_NODES
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001597 help
Mike Travis1184dc22008-05-12 21:21:12 +02001598 Specify the maximum number of NUMA Nodes available on the target
Matt LaPlante692105b2009-01-26 11:12:25 +01001599 system. Increases memory reserved to accommodate various tables.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001600
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001601config ARCH_FLATMEM_ENABLE
1602 def_bool y
Tejun Heo3b166512011-04-01 11:15:12 +02001603 depends on X86_32 && !NUMA
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001604
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001605config ARCH_SPARSEMEM_ENABLE
1606 def_bool y
Kees Cook6ea30382012-10-02 11:16:47 -07001607 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001608 select SPARSEMEM_STATIC if X86_32
1609 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1610
Tejun Heo3b166512011-04-01 11:15:12 +02001611config ARCH_SPARSEMEM_DEFAULT
Mike Rapoport6ad57f72019-04-24 16:24:11 +03001612 def_bool X86_64 || (NUMA && X86_32)
Tejun Heo3b166512011-04-01 11:15:12 +02001613
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001614config ARCH_SELECT_MEMORY_MODEL
1615 def_bool y
Christoph Lameterb2632952008-01-30 13:30:47 +01001616 depends on ARCH_SPARSEMEM_ENABLE
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001617
1618config ARCH_MEMORY_PROBE
Toshi Kania0842b72013-07-19 11:47:48 -06001619 bool "Enable sysfs memory/probe interface"
Jan Beulich3120e252012-09-10 12:41:45 +01001620 depends on X86_64 && MEMORY_HOTPLUG
Toshi Kania0842b72013-07-19 11:47:48 -06001621 help
1622 This option enables a sysfs memory/probe interface for testing.
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001623 See Documentation/admin-guide/mm/memory-hotplug.rst for more information.
Toshi Kania0842b72013-07-19 11:47:48 -06001624 If you are unsure how to answer this question, answer N.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001625
Tejun Heo3b166512011-04-01 11:15:12 +02001626config ARCH_PROC_KCORE_TEXT
1627 def_bool y
1628 depends on X86_64 && PROC_KCORE
1629
Avi Kivitya29815a2010-01-10 16:28:09 +02001630config ILLEGAL_POINTER_VALUE
Krzysztof Kozlowskib03b0162019-11-21 04:21:09 +01001631 hex
1632 default 0 if X86_32
1633 default 0xdead000000000000 if X86_64
Avi Kivitya29815a2010-01-10 16:28:09 +02001634
Dan Williams7a678322015-08-19 00:34:34 -04001635config X86_PMEM_LEGACY_DEVICE
1636 bool
1637
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001638config X86_PMEM_LEGACY
Dan Williams7a678322015-08-19 00:34:34 -04001639 tristate "Support non-standard NVDIMMs and ADR protected memory"
Dan Williams9f53f9f2015-06-09 15:33:45 -04001640 depends on PHYS_ADDR_T_64BIT
1641 depends on BLK_DEV
Dan Williams7a678322015-08-19 00:34:34 -04001642 select X86_PMEM_LEGACY_DEVICE
Dan Williams7b27a862020-02-16 12:01:16 -08001643 select NUMA_KEEP_MEMINFO if NUMA
Dan Williams9f53f9f2015-06-09 15:33:45 -04001644 select LIBNVDIMM
Christoph Hellwigec776ef2015-04-01 09:12:18 +02001645 help
1646 Treat memory marked using the non-standard e820 type of 12 as used
1647 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1648 The kernel will offer these regions to the 'pmem' driver so
1649 they can be used for persistent storage.
1650
1651 Say Y if unsure.
1652
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001653config HIGHPTE
1654 bool "Allocate 3rd-level pagetables from highmem"
Jan Beulich6fc108a2010-04-21 15:23:44 +01001655 depends on HIGHMEM
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001656 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001657 The VM uses one page table entry for each page of physical memory.
1658 For systems with a lot of RAM, this can be wasteful of precious
1659 low memory. Setting this option will put user-space page table
1660 entries in high memory.
1661
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001662config X86_CHECK_BIOS_CORRUPTION
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001663 bool "Check for low memory corruption"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001664 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001665 Periodically check for memory corruption in low memory, which
1666 is suspected to be caused by BIOS. Even when enabled in the
1667 configuration, it is disabled at runtime. Enable it by
1668 setting "memory_corruption_check=1" on the kernel command
1669 line. By default it scans the low 64k of memory every 60
1670 seconds; see the memory_corruption_check_size and
1671 memory_corruption_check_period parameters in
Mauro Carvalho Chehab8c27ceff32016-10-18 10:12:27 -02001672 Documentation/admin-guide/kernel-parameters.rst to adjust this.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001673
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001674 When enabled with the default parameters, this option has
1675 almost no overhead, as it reserves a relatively small amount
1676 of memory and scans it infrequently. It both detects corruption
1677 and prevents it from affecting the running system.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001678
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001679 It is, however, intended as a diagnostic tool; if repeatable
1680 BIOS-originated corruption always affects the same memory,
1681 you can use memmap= to prevent the kernel from using that
1682 memory.
Jeremy Fitzhardinge9f077872008-09-07 01:51:34 -07001683
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001684config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001685 bool "Set the default setting of memory_corruption_check"
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001686 depends on X86_CHECK_BIOS_CORRUPTION
1687 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001688 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001689 Set whether the default state of memory_corruption_check is
1690 on or off.
Jeremy Fitzhardingec885df52008-09-07 02:37:32 -07001691
H. Peter Anvin9ea77bd2010-08-25 16:38:20 -07001692config X86_RESERVE_LOW
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001693 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1694 default 64
1695 range 4 640
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001696 help
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001697 Specify the amount of low memory to reserve for the BIOS.
Ingo Molnarfc381512008-09-16 10:07:34 +02001698
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001699 The first page contains BIOS data structures that the kernel
1700 must not use, so that page must always be reserved.
Ingo Molnarfc381512008-09-16 10:07:34 +02001701
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001702 By default we reserve the first 64K of physical RAM, as a
1703 number of BIOSes are known to corrupt that memory range
1704 during events such as suspend/resume or monitor cable
1705 insertion, so it must not be used by the kernel.
Ingo Molnarfc381512008-09-16 10:07:34 +02001706
H. Peter Anvind0cd7422010-08-24 17:32:04 -07001707 You can set this to 4 if you are absolutely sure that you
1708 trust the BIOS to get all its memory reservations and usages
1709 right. If you know your BIOS have problems beyond the
1710 default 64K area, you can set this to 640 to avoid using the
1711 entire low memory range.
1712
1713 If you have doubts about the BIOS (e.g. suspend/resume does
1714 not work or there's kernel crashes after certain hardware
1715 hotplug events) then you might want to enable
1716 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1717 typical corruption patterns.
1718
1719 Leave this to the default value of 64 if you are unsure.
Ingo Molnarfc381512008-09-16 10:07:34 +02001720
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001721config MATH_EMULATION
1722 bool
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07001723 depends on MODIFY_LDT_SYSCALL
Arnd Bergmann87d60212019-10-01 16:23:35 +02001724 prompt "Math emulation" if X86_32 && (M486SX || MELAN)
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001725 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001726 Linux can emulate a math coprocessor (used for floating point
1727 operations) if you don't have one. 486DX and Pentium processors have
1728 a math coprocessor built in, 486SX and 386 do not, unless you added
1729 a 487DX or 387, respectively. (The messages during boot time can
1730 give you some hints here ["man dmesg"].) Everyone needs either a
1731 coprocessor or this emulation.
1732
1733 If you don't have a math coprocessor, you need to say Y here; if you
1734 say Y here even though you have a coprocessor, the coprocessor will
1735 be used nevertheless. (This behavior can be changed with the kernel
1736 command line option "no387", which comes handy if your coprocessor
1737 is broken. Try "man bootparam" or see the documentation of your boot
1738 loader (lilo or loadlin) about how to pass options to the kernel at
1739 boot time.) This means that it is a good idea to say Y here if you
1740 intend to use this kernel on different machines.
1741
1742 More information about the internals of the Linux math coprocessor
1743 emulation can be found in <file:arch/x86/math-emu/README>.
1744
1745 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1746 kernel, it won't hurt.
1747
1748config MTRR
Jan Beulich6fc108a2010-04-21 15:23:44 +01001749 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001750 prompt "MTRR (Memory Type Range Register) support" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001751 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001752 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1753 the Memory Type Range Registers (MTRRs) may be used to control
1754 processor access to memory ranges. This is most useful if you have
1755 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1756 allows bus write transfers to be combined into a larger transfer
1757 before bursting over the PCI/AGP bus. This can increase performance
1758 of image write operations 2.5 times or more. Saying Y here creates a
1759 /proc/mtrr file which may be used to manipulate your processor's
1760 MTRRs. Typically the X server should use this.
1761
1762 This code has a reasonably generic interface so that similar
1763 control registers on other processors can be easily supported
1764 as well:
1765
1766 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1767 Registers (ARRs) which provide a similar functionality to MTRRs. For
1768 these, the ARRs are used to emulate the MTRRs.
1769 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1770 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1771 write-combining. All of these processors are supported by this code
1772 and it makes sense to say Y here if you have one of them.
1773
1774 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1775 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1776 can lead to all sorts of problems, so it's good to say Y here.
1777
1778 You can safely say Y even if your machine doesn't have MTRRs, you'll
1779 just add about 9 KB to your kernel.
1780
Mauro Carvalho Chehabcb1aaeb2019-06-07 15:54:32 -03001781 See <file:Documentation/x86/mtrr.rst> for more information.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001782
Yinghai Lu95ffa242008-04-29 03:52:33 -07001783config MTRR_SANITIZER
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001784 def_bool y
Yinghai Lu95ffa242008-04-29 03:52:33 -07001785 prompt "MTRR cleanup support"
1786 depends on MTRR
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001787 help
Thomas Gleixneraba37282008-07-15 14:48:48 +02001788 Convert MTRR layout from continuous to discrete, so X drivers can
1789 add writeback entries.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001790
Thomas Gleixneraba37282008-07-15 14:48:48 +02001791 Can be disabled with disable_mtrr_cleanup on the kernel command line.
Matt LaPlante692105b2009-01-26 11:12:25 +01001792 The largest mtrr entry size for a continuous block can be set with
Thomas Gleixneraba37282008-07-15 14:48:48 +02001793 mtrr_chunk_size.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001794
Yinghai Lu2ffb3502008-09-30 16:29:40 -07001795 If unsure, say Y.
Yinghai Lu95ffa242008-04-29 03:52:33 -07001796
1797config MTRR_SANITIZER_ENABLE_DEFAULT
Yinghai Luf5098d62008-04-29 20:25:58 -07001798 int "MTRR cleanup enable value (0-1)"
1799 range 0 1
1800 default "0"
Yinghai Lu95ffa242008-04-29 03:52:33 -07001801 depends on MTRR_SANITIZER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001802 help
Yinghai Luf5098d62008-04-29 20:25:58 -07001803 Enable mtrr cleanup default value
Yinghai Lu95ffa242008-04-29 03:52:33 -07001804
Yinghai Lu12031a62008-05-02 02:40:22 -07001805config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1806 int "MTRR cleanup spare reg num (0-7)"
1807 range 0 7
1808 default "1"
1809 depends on MTRR_SANITIZER
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001810 help
Yinghai Lu12031a62008-05-02 02:40:22 -07001811 mtrr cleanup spare entries default, it can be changed via
Thomas Gleixneraba37282008-07-15 14:48:48 +02001812 mtrr_spare_reg_nr=N on the kernel command line.
Yinghai Lu12031a62008-05-02 02:40:22 -07001813
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001814config X86_PAT
Jan Beulich6fc108a2010-04-21 15:23:44 +01001815 def_bool y
David Rientjes6a108a12011-01-20 14:44:16 -08001816 prompt "x86 PAT support" if EXPERT
Ingo Molnar2a8a2712008-04-26 10:26:52 +02001817 depends on MTRR
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001818 help
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001819 Use PAT attributes to setup page level cache control.
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001820
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001821 PATs are the modern equivalents of MTRRs and are much more
1822 flexible than MTRRs.
1823
1824 Say N here if you see bootup problems (boot crash, boot hang,
Venki Pallipadi042b78e2008-03-24 14:22:35 -07001825 spontaneous reboots) or a non-working video driver.
venkatesh.pallipadi@intel.com2e5d9c82008-03-18 17:00:14 -07001826
1827 If unsure, say Y.
1828
Venkatesh Pallipadi46cf98c2009-07-10 09:57:37 -07001829config ARCH_USES_PG_UNCACHED
1830 def_bool y
1831 depends on X86_PAT
1832
H. Peter Anvin628c6242011-07-31 13:59:29 -07001833config ARCH_RANDOM
1834 def_bool y
1835 prompt "x86 architectural random number generator" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001836 help
H. Peter Anvin628c6242011-07-31 13:59:29 -07001837 Enable the x86 architectural RDRAND instruction
1838 (Intel Bull Mountain technology) to generate random numbers.
1839 If supported, this is a high bandwidth, cryptographically
1840 secure hardware random number generator.
1841
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001842config X86_SMAP
1843 def_bool y
1844 prompt "Supervisor Mode Access Prevention" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001845 help
H. Peter Anvin51ae4a22012-09-21 12:43:10 -07001846 Supervisor Mode Access Prevention (SMAP) is a security
1847 feature in newer Intel processors. There is a small
1848 performance cost if this enabled and turned on; there is
1849 also a small increase in the kernel size if this is enabled.
1850
1851 If unsure, say Y.
1852
Babu Mogerb9718802019-11-05 21:25:32 +00001853config X86_UMIP
Ricardo Neri796ebc82017-11-13 22:29:42 -08001854 def_bool y
Babu Mogerb9718802019-11-05 21:25:32 +00001855 prompt "User Mode Instruction Prevention" if EXPERT
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001856 help
Babu Mogerb9718802019-11-05 21:25:32 +00001857 User Mode Instruction Prevention (UMIP) is a security feature in
1858 some x86 processors. If enabled, a general protection fault is
1859 issued if the SGDT, SLDT, SIDT, SMSW or STR instructions are
1860 executed in user mode. These instructions unnecessarily expose
1861 information about the hardware state.
Ricardo Neri796ebc82017-11-13 22:29:42 -08001862
1863 The vast majority of applications do not use these instructions.
1864 For the very few that do, software emulation is provided in
1865 specific cases in protected and virtual-8086 modes. Emulated
1866 results are dummy.
Ricardo Neriaa35f892017-11-05 18:27:54 -08001867
Dave Hansen35e97792016-02-12 13:02:00 -08001868config X86_INTEL_MEMORY_PROTECTION_KEYS
Babu Moger38f3e772020-05-28 11:08:23 -05001869 prompt "Memory Protection Keys"
Dave Hansen35e97792016-02-12 13:02:00 -08001870 def_bool y
Dave Hansen284244a2016-02-12 13:02:28 -08001871 # Note: only available in 64-bit mode
Babu Moger38f3e772020-05-28 11:08:23 -05001872 depends on X86_64 && (CPU_SUP_INTEL || CPU_SUP_AMD)
Ingo Molnar52c8e602016-11-15 10:15:03 +01001873 select ARCH_USES_HIGH_VMA_FLAGS
1874 select ARCH_HAS_PKEYS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001875 help
Dave Hansen284244a2016-02-12 13:02:28 -08001876 Memory Protection Keys provides a mechanism for enforcing
1877 page-based protections, but without requiring modification of the
1878 page tables when an application changes protection domains.
1879
Mauro Carvalho Chehab1eecbcd2019-06-07 15:54:31 -03001880 For details, see Documentation/core-api/protection-keys.rst
Dave Hansen284244a2016-02-12 13:02:28 -08001881
1882 If unsure, say y.
Dave Hansen35e97792016-02-12 13:02:00 -08001883
Michal Hockodb616172019-10-23 12:35:50 +02001884choice
1885 prompt "TSX enable mode"
1886 depends on CPU_SUP_INTEL
1887 default X86_INTEL_TSX_MODE_OFF
1888 help
1889 Intel's TSX (Transactional Synchronization Extensions) feature
1890 allows to optimize locking protocols through lock elision which
1891 can lead to a noticeable performance boost.
1892
1893 On the other hand it has been shown that TSX can be exploited
1894 to form side channel attacks (e.g. TAA) and chances are there
1895 will be more of those attacks discovered in the future.
1896
1897 Therefore TSX is not enabled by default (aka tsx=off). An admin
1898 might override this decision by tsx=on the command line parameter.
1899 Even with TSX enabled, the kernel will attempt to enable the best
1900 possible TAA mitigation setting depending on the microcode available
1901 for the particular machine.
1902
1903 This option allows to set the default tsx mode between tsx=on, =off
1904 and =auto. See Documentation/admin-guide/kernel-parameters.txt for more
1905 details.
1906
1907 Say off if not sure, auto if TSX is in use but it should be used on safe
1908 platforms or on if TSX is in use and the security aspect of tsx is not
1909 relevant.
1910
1911config X86_INTEL_TSX_MODE_OFF
1912 bool "off"
1913 help
1914 TSX is disabled if possible - equals to tsx=off command line parameter.
1915
1916config X86_INTEL_TSX_MODE_ON
1917 bool "on"
1918 help
1919 TSX is always enabled on TSX capable HW - equals the tsx=on command
1920 line parameter.
1921
1922config X86_INTEL_TSX_MODE_AUTO
1923 bool "auto"
1924 help
1925 TSX is enabled on TSX capable HW that is believed to be safe against
1926 side channel attacks- equals the tsx=auto command line parameter.
1927endchoice
1928
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001929config EFI
Jan Beulich9ba16082008-10-15 22:01:38 -07001930 bool "EFI runtime service support"
Huang, Ying5b836832008-01-30 13:31:19 +01001931 depends on ACPI
Sergey Vlasovf6ce5002013-04-16 18:31:08 +04001932 select UCS2_STRING
Ard Biesheuvel022ee6c2014-06-26 12:09:05 +02001933 select EFI_RUNTIME_WRAPPERS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001934 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001935 This enables the kernel to use EFI runtime services that are
1936 available (such as the EFI variable services).
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001937
Ingo Molnar8f9ca472009-02-05 16:21:53 +01001938 This option is only useful on systems that have EFI firmware.
1939 In addition, you should use the latest ELILO loader available
1940 at <http://elilo.sourceforge.net> in order to take advantage
1941 of EFI runtime services. However, even with this option, the
1942 resultant kernel should continue to boot on existing non-EFI
1943 platforms.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001944
Matt Fleming291f3632011-12-12 21:27:52 +00001945config EFI_STUB
Ard Biesheuvel8f24f8c2019-12-24 16:10:12 +01001946 bool "EFI stub support"
1947 depends on EFI && !X86_USE_3DNOW
1948 depends on $(cc-option,-mabi=ms) || X86_32
1949 select RELOCATABLE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001950 help
Ard Biesheuvel8f24f8c2019-12-24 16:10:12 +01001951 This kernel feature allows a bzImage to be loaded directly
Matt Fleming291f3632011-12-12 21:27:52 +00001952 by EFI firmware without the use of a bootloader.
1953
Mauro Carvalho Chehab4f4cfa62019-06-27 14:56:51 -03001954 See Documentation/admin-guide/efi-stub.rst for more information.
Matt Fleming0c759662012-03-16 12:03:13 +00001955
Matt Fleming7d453ee2014-01-10 18:52:06 +00001956config EFI_MIXED
1957 bool "EFI mixed-mode support"
1958 depends on EFI_STUB && X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001959 help
Matt Fleming7d453ee2014-01-10 18:52:06 +00001960 Enabling this feature allows a 64-bit kernel to be booted
1961 on a 32-bit firmware, provided that your CPU supports 64-bit
1962 mode.
1963
1964 Note that it is not possible to boot a mixed-mode enabled
1965 kernel via the EFI boot stub - a bootloader that supports
1966 the EFI handover protocol must be used.
1967
1968 If unsure, say N.
1969
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001970config SECCOMP
Harvey Harrison3c2362e2008-01-30 13:31:03 +01001971 def_bool y
1972 prompt "Enable seccomp to safely compute untrusted bytecode"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001973 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001974 This kernel feature is useful for number crunching applications
1975 that may need to compute untrusted bytecode during their
1976 execution. By using pipes or other transports made available to
1977 the process as file descriptors supporting the read/write
1978 syscalls, it's possible to isolate those applications in
1979 their own address space using seccomp. Once seccomp is
Alexey Dobriyan9c0bbee2008-09-09 11:01:31 +04001980 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001981 and the task is only allowed to execute a few safe syscalls
1982 defined by each seccomp mode.
1983
1984 If unsure, say Y. Only embedded should say N here.
1985
Masahiro Yamada8636a1f2018-12-11 20:01:04 +09001986source "kernel/Kconfig.hz"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001987
1988config KEXEC
1989 bool "kexec system call"
Dave Young2965faa2015-09-09 15:38:55 -07001990 select KEXEC_CORE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09001991 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01001992 kexec is a system call that implements the ability to shutdown your
1993 current kernel, and to start another kernel. It is like a reboot
1994 but it is independent of the system firmware. And like a reboot
1995 you can start any kernel with it, not just Linux.
1996
1997 The name comes from the similarity to the exec system call.
1998
1999 It is an ongoing process to be certain the hardware in a machine
2000 is properly shutdown, so do not be surprised if this code does not
Geert Uytterhoevenbf220692013-08-20 21:38:03 +02002001 initially work for you. As of this writing the exact hardware
2002 interface is strongly in flux, so no good recommendation can be
2003 made.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002004
Vivek Goyal74ca3172014-08-29 15:18:46 -07002005config KEXEC_FILE
2006 bool "kexec file based system call"
Dave Young2965faa2015-09-09 15:38:55 -07002007 select KEXEC_CORE
Vivek Goyal74ca3172014-08-29 15:18:46 -07002008 select BUILD_BIN2C
Vivek Goyal74ca3172014-08-29 15:18:46 -07002009 depends on X86_64
2010 depends on CRYPTO=y
2011 depends on CRYPTO_SHA256=y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002012 help
Vivek Goyal74ca3172014-08-29 15:18:46 -07002013 This is new version of kexec system call. This system call is
2014 file based and takes file descriptors as system call argument
2015 for kernel and initramfs as opposed to list of segments as
2016 accepted by previous system call.
2017
AKASHI Takahirob799a092018-04-13 15:35:45 -07002018config ARCH_HAS_KEXEC_PURGATORY
2019 def_bool KEXEC_FILE
2020
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07002021config KEXEC_SIG
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002022 bool "Verify kernel signature during kexec_file_load() syscall"
Vivek Goyal74ca3172014-08-29 15:18:46 -07002023 depends on KEXEC_FILE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002024 help
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07002025
2026 This option makes the kexec_file_load() syscall check for a valid
2027 signature of the kernel image. The image can still be loaded without
2028 a valid signature unless you also enable KEXEC_SIG_FORCE, though if
2029 there's a signature that we can check, then it must be valid.
2030
2031 In addition to this option, you need to enable signature
2032 verification for the corresponding kernel image type being
2033 loaded in order for this to work.
2034
2035config KEXEC_SIG_FORCE
2036 bool "Require a valid signature in kexec_file_load() syscall"
2037 depends on KEXEC_SIG
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002038 help
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002039 This option makes kernel signature verification mandatory for
Borislav Petkovd8eb8942015-03-13 14:04:37 +01002040 the kexec_file_load() syscall.
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002041
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002042config KEXEC_BZIMAGE_VERIFY_SIG
2043 bool "Enable bzImage signature verification support"
Jiri Bohac99d5cadf2019-08-19 17:17:44 -07002044 depends on KEXEC_SIG
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002045 depends on SIGNED_PE_FILE_VERIFICATION
2046 select SYSTEM_TRUSTED_KEYRING
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002047 help
Vivek Goyal8e7d8382014-08-08 14:26:13 -07002048 Enable bzImage signature verification support.
2049
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002050config CRASH_DUMP
Pavel Machek04b69442008-08-14 17:16:50 +02002051 bool "kernel crash dumps"
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002052 depends on X86_64 || (X86_32 && HIGHMEM)
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002053 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002054 Generate crash dump after being started by kexec.
2055 This should be normally only set in special crash dump kernels
2056 which are loaded in the main kernel with kexec-tools into
2057 a specially reserved region and then later executed after
2058 a crash by kdump/kexec. The crash dump kernel must be compiled
2059 to a memory address not used by the main kernel or BIOS using
2060 PHYSICAL_START, or it must be built as a relocatable image
2061 (CONFIG_RELOCATABLE=y).
Mauro Carvalho Chehab330d4812019-06-13 15:21:39 -03002062 For more details see Documentation/admin-guide/kdump/kdump.rst
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002063
Huang Ying3ab83522008-07-25 19:45:07 -07002064config KEXEC_JUMP
Kees Cook6ea30382012-10-02 11:16:47 -07002065 bool "kexec jump"
Huang Yingfee7b0d2009-03-10 10:57:16 +08002066 depends on KEXEC && HIBERNATION
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002067 help
Huang Ying89081d12008-07-25 19:45:10 -07002068 Jump between original kernel and kexeced kernel and invoke
2069 code in physical address mode via KEXEC
Huang Ying3ab83522008-07-25 19:45:07 -07002070
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002071config PHYSICAL_START
David Rientjes6a108a12011-01-20 14:44:16 -08002072 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002073 default "0x1000000"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002074 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002075 This gives the physical address where the kernel is loaded.
2076
2077 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2078 bzImage will decompress itself to above physical address and
2079 run from there. Otherwise, bzImage will run from the address where
2080 it has been loaded by the boot loader and will ignore above physical
2081 address.
2082
2083 In normal kdump cases one does not have to set/change this option
2084 as now bzImage can be compiled as a completely relocatable image
2085 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2086 address. This option is mainly useful for the folks who don't want
2087 to use a bzImage for capturing the crash dump and want to use a
2088 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2089 to be specifically compiled to run from a specific memory area
2090 (normally a reserved region) and this option comes handy.
2091
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002092 So if you are using bzImage for capturing the crash dump,
2093 leave the value here unchanged to 0x1000000 and set
2094 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2095 for capturing the crash dump change this value to start of
2096 the reserved region. In other words, it can be set based on
2097 the "X" value as specified in the "crashkernel=YM@XM"
2098 command line boot parameter passed to the panic-ed
Mauro Carvalho Chehab330d4812019-06-13 15:21:39 -03002099 kernel. Please take a look at Documentation/admin-guide/kdump/kdump.rst
H. Peter Anvinceefccc2009-05-11 16:12:16 -07002100 for more details about crash dumps.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002101
2102 Usage of bzImage for capturing the crash dump is recommended as
2103 one does not have to build two kernels. Same kernel can be used
2104 as production kernel and capture kernel. Above option should have
2105 gone away after relocatable bzImage support is introduced. But it
2106 is present because there are users out there who continue to use
2107 vmlinux for dump capture. This option should go away down the
2108 line.
2109
2110 Don't change this unless you know what you are doing.
2111
2112config RELOCATABLE
H. Peter Anvin26717802009-05-07 14:19:34 -07002113 bool "Build a relocatable kernel"
2114 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002115 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002116 This builds a kernel image that retains relocation information
2117 so it can be loaded someplace besides the default 1MB.
2118 The relocations tend to make the kernel binary about 10% larger,
2119 but are discarded at runtime.
2120
2121 One use is for the kexec on panic case where the recovery kernel
2122 must live at a different physical address than the primary
2123 kernel.
2124
2125 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2126 it has been loaded at and the compile time physical address
Kees Cook8ab38202013-10-10 17:18:14 -07002127 (CONFIG_PHYSICAL_START) is used as the minimum location.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002128
Kees Cook8ab38202013-10-10 17:18:14 -07002129config RANDOMIZE_BASE
Baoquan Hee8581e32016-04-20 13:55:43 -07002130 bool "Randomize the address of the kernel image (KASLR)"
Kees Cook8ab38202013-10-10 17:18:14 -07002131 depends on RELOCATABLE
Ingo Molnar6807c842017-04-18 11:08:12 +02002132 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002133 help
Baoquan Hee8581e32016-04-20 13:55:43 -07002134 In support of Kernel Address Space Layout Randomization (KASLR),
2135 this randomizes the physical address at which the kernel image
2136 is decompressed and the virtual address where the kernel
2137 image is mapped, as a security feature that deters exploit
2138 attempts relying on knowledge of the location of kernel
2139 code internals.
Kees Cook8ab38202013-10-10 17:18:14 -07002140
Kees Cooked9f0072016-05-25 15:45:33 -07002141 On 64-bit, the kernel physical and virtual addresses are
2142 randomized separately. The physical address will be anywhere
2143 between 16MB and the top of physical memory (up to 64TB). The
2144 virtual address will be randomized from 16MB up to 1GB (9 bits
2145 of entropy). Note that this also reduces the memory space
2146 available to kernel modules from 1.5GB to 1GB.
2147
2148 On 32-bit, the kernel physical and virtual addresses are
2149 randomized together. They will be randomized from 16MB up to
2150 512MB (8 bits of entropy).
Kees Cook8ab38202013-10-10 17:18:14 -07002151
Baoquan Hee8581e32016-04-20 13:55:43 -07002152 Entropy is generated using the RDRAND instruction if it is
2153 supported. If RDTSC is supported, its value is mixed into
2154 the entropy pool as well. If neither RDRAND nor RDTSC are
Kees Cooked9f0072016-05-25 15:45:33 -07002155 supported, then entropy is read from the i8254 timer. The
2156 usable entropy is limited by the kernel being built using
2157 2GB addressing, and that PHYSICAL_ALIGN must be at a
2158 minimum of 2MB. As a result, only 10 bits of entropy are
2159 theoretically possible, but the implementations are further
2160 limited due to memory layouts.
Kees Cookda2b6fb2013-12-10 12:27:45 -08002161
Ingo Molnar6807c842017-04-18 11:08:12 +02002162 If unsure, say Y.
Kees Cook8ab38202013-10-10 17:18:14 -07002163
2164# Relocation on x86 needs some additional build support
H. Peter Anvin845adf72009-05-05 21:20:51 -07002165config X86_NEED_RELOCS
2166 def_bool y
Kees Cook8ab38202013-10-10 17:18:14 -07002167 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
H. Peter Anvin845adf72009-05-05 21:20:51 -07002168
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002169config PHYSICAL_ALIGN
Kees Cooka0215062013-07-08 09:15:17 -07002170 hex "Alignment value to which kernel should be aligned"
Kees Cook8ab38202013-10-10 17:18:14 -07002171 default "0x200000"
Kees Cooka0215062013-07-08 09:15:17 -07002172 range 0x2000 0x1000000 if X86_32
2173 range 0x200000 0x1000000 if X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002174 help
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002175 This value puts the alignment restrictions on physical address
2176 where kernel is loaded and run from. Kernel is compiled for an
2177 address which meets above alignment restriction.
2178
2179 If bootloader loads the kernel at a non-aligned address and
2180 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2181 address aligned to above value and run from there.
2182
2183 If bootloader loads the kernel at a non-aligned address and
2184 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2185 load address and decompress itself to the address it has been
2186 compiled for and run from there. The address for which kernel is
2187 compiled already meets above alignment restrictions. Hence the
2188 end result is that kernel runs from a physical address meeting
2189 above alignment restrictions.
2190
Kees Cooka0215062013-07-08 09:15:17 -07002191 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2192 this value must be a multiple of 0x200000.
2193
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002194 Don't change this unless you know what you are doing.
2195
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002196config DYNAMIC_MEMORY_LAYOUT
2197 bool
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002198 help
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002199 This option makes base addresses of vmalloc and vmemmap as well as
2200 __PAGE_OFFSET movable during boot.
2201
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002202config RANDOMIZE_MEMORY
2203 bool "Randomize the kernel memory sections"
2204 depends on X86_64
2205 depends on RANDOMIZE_BASE
Kirill A. Shutemoveedb92a2018-02-14 14:16:50 +03002206 select DYNAMIC_MEMORY_LAYOUT
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002207 default RANDOMIZE_BASE
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002208 help
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002209 Randomizes the base virtual address of kernel memory sections
2210 (physical memory mapping, vmalloc & vmemmap). This security feature
2211 makes exploits relying on predictable memory locations less reliable.
2212
2213 The order of allocations remains unchanged. Entropy is generated in
2214 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2215 configuration have in average 30,000 different possible virtual
2216 addresses for each memory section.
2217
Ingo Molnar6807c842017-04-18 11:08:12 +02002218 If unsure, say Y.
Thomas Garnier0483e1f2016-06-21 17:47:02 -07002219
Thomas Garnier90397a42016-06-21 17:47:06 -07002220config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2221 hex "Physical memory mapping padding" if EXPERT
2222 depends on RANDOMIZE_MEMORY
2223 default "0xa" if MEMORY_HOTPLUG
2224 default "0x0"
2225 range 0x1 0x40 if MEMORY_HOTPLUG
2226 range 0x0 0x40
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002227 help
Thomas Garnier90397a42016-06-21 17:47:06 -07002228 Define the padding in terabytes added to the existing physical
2229 memory size during kernel memory randomization. It is useful
2230 for memory hotplug support but reduces the entropy available for
2231 address randomization.
2232
2233 If unsure, leave at the default value.
2234
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002235config HOTPLUG_CPU
Thomas Gleixnerbebd0242019-03-26 17:36:06 +01002236 def_bool y
Stephen Rothwell40b31362013-05-21 13:49:35 +10002237 depends on SMP
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002238
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002239config BOOTPARAM_HOTPLUG_CPU0
2240 bool "Set default setting of cpu0_hotpluggable"
Kees Cook2c922cd2013-01-22 13:01:19 -08002241 depends on HOTPLUG_CPU
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002242 help
Fenghua Yu80aa1df2012-11-13 11:32:39 -08002243 Set whether default state of cpu0_hotpluggable is on or off.
2244
2245 Say Y here to enable CPU0 hotplug by default. If this switch
2246 is turned on, there is no need to give cpu0_hotplug kernel
2247 parameter and the CPU0 hotplug feature is enabled by default.
2248
2249 Please note: there are two known CPU0 dependencies if you want
2250 to enable the CPU0 hotplug feature either by this switch or by
2251 cpu0_hotplug kernel parameter.
2252
2253 First, resume from hibernate or suspend always starts from CPU0.
2254 So hibernate and suspend are prevented if CPU0 is offline.
2255
2256 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2257 offline if any interrupt can not migrate out of CPU0. There may
2258 be other CPU0 dependencies.
2259
2260 Please make sure the dependencies are under your control before
2261 you enable this feature.
2262
2263 Say N if you don't want to enable CPU0 hotplug feature by default.
2264 You still can enable the CPU0 hotplug feature at boot by kernel
2265 parameter cpu0_hotplug.
2266
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002267config DEBUG_HOTPLUG_CPU0
2268 def_bool n
2269 prompt "Debug CPU0 hotplug"
Kees Cook2c922cd2013-01-22 13:01:19 -08002270 depends on HOTPLUG_CPU
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002271 help
Fenghua Yua71c8bc2012-11-13 11:32:51 -08002272 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2273 soon as possible and boots up userspace with CPU0 offlined. User
2274 can online CPU0 back after boot time.
2275
2276 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2277 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2278 compilation or giving cpu0_hotplug kernel parameter at boot.
2279
2280 If unsure, say N.
2281
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002282config COMPAT_VDSO
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002283 def_bool n
2284 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
Ingo Molnar953fee12016-11-15 10:22:52 +01002285 depends on COMPAT_32
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002286 help
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002287 Certain buggy versions of glibc will crash if they are
2288 presented with a 32-bit vDSO that is not mapped at the address
2289 indicated in its segment table.
Randy Dunlape84446d2009-11-10 15:46:52 -08002290
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002291 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2292 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2293 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2294 the only released version with the bug, but OpenSUSE 9
2295 contains a buggy "glibc 2.3.2".
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002296
Andy Lutomirskib0b49f22014-03-13 16:01:26 -07002297 The symptom of the bug is that everything crashes on startup, saying:
2298 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2299
2300 Saying Y here changes the default value of the vdso32 boot
2301 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2302 This works around the glibc bug but hurts performance.
2303
2304 If unsure, say N: if you are compiling your own kernel, you
2305 are unlikely to be using a buggy version of glibc.
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002306
Kees Cook3dc33bd2015-08-12 17:55:19 -07002307choice
2308 prompt "vsyscall table for legacy applications"
2309 depends on X86_64
Andy Lutomirski625b7b72019-06-26 21:45:07 -07002310 default LEGACY_VSYSCALL_XONLY
Kees Cook3dc33bd2015-08-12 17:55:19 -07002311 help
2312 Legacy user code that does not know how to find the vDSO expects
2313 to be able to issue three syscalls by calling fixed addresses in
2314 kernel space. Since this location is not randomized with ASLR,
2315 it can be used to assist security vulnerability exploitation.
2316
2317 This setting can be changed at boot time via the kernel command
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002318 line parameter vsyscall=[emulate|xonly|none].
Kees Cook3dc33bd2015-08-12 17:55:19 -07002319
2320 On a system with recent enough glibc (2.14 or newer) and no
2321 static binaries, you can say None without a performance penalty
2322 to improve security.
2323
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002324 If unsure, select "Emulate execution only".
Kees Cook3dc33bd2015-08-12 17:55:19 -07002325
Kees Cook3dc33bd2015-08-12 17:55:19 -07002326 config LEGACY_VSYSCALL_EMULATE
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002327 bool "Full emulation"
Kees Cook3dc33bd2015-08-12 17:55:19 -07002328 help
Andy Lutomirskibd49e162019-06-26 21:45:03 -07002329 The kernel traps and emulates calls into the fixed vsyscall
2330 address mapping. This makes the mapping non-executable, but
2331 it still contains readable known contents, which could be
2332 used in certain rare security vulnerability exploits. This
2333 configuration is recommended when using legacy userspace
2334 that still uses vsyscalls along with legacy binary
2335 instrumentation tools that require code to be readable.
2336
2337 An example of this type of legacy userspace is running
2338 Pin on an old binary that still uses vsyscalls.
2339
2340 config LEGACY_VSYSCALL_XONLY
2341 bool "Emulate execution only"
2342 help
2343 The kernel traps and emulates calls into the fixed vsyscall
2344 address mapping and does not allow reads. This
2345 configuration is recommended when userspace might use the
2346 legacy vsyscall area but support for legacy binary
2347 instrumentation of legacy code is not needed. It mitigates
2348 certain uses of the vsyscall area as an ASLR-bypassing
2349 buffer.
Kees Cook3dc33bd2015-08-12 17:55:19 -07002350
2351 config LEGACY_VSYSCALL_NONE
2352 bool "None"
2353 help
2354 There will be no vsyscall mapping at all. This will
2355 eliminate any risk of ASLR bypass due to the vsyscall
2356 fixed address mapping. Attempts to use the vsyscalls
2357 will be reported to dmesg, so that either old or
2358 malicious userspace programs can be identified.
2359
2360endchoice
2361
Tim Bird516cbf32008-08-12 12:52:36 -07002362config CMDLINE_BOOL
2363 bool "Built-in kernel command line"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002364 help
Tim Bird516cbf32008-08-12 12:52:36 -07002365 Allow for specifying boot arguments to the kernel at
2366 build time. On some systems (e.g. embedded ones), it is
2367 necessary or convenient to provide some or all of the
2368 kernel boot arguments with the kernel itself (that is,
2369 to not rely on the boot loader to provide them.)
2370
2371 To compile command line arguments into the kernel,
2372 set this option to 'Y', then fill in the
Sébastien Hinderer69711ca2015-07-08 00:02:01 +02002373 boot arguments in CONFIG_CMDLINE.
Tim Bird516cbf32008-08-12 12:52:36 -07002374
2375 Systems with fully functional boot loaders (i.e. non-embedded)
2376 should leave this option set to 'N'.
2377
2378config CMDLINE
2379 string "Built-in kernel command string"
2380 depends on CMDLINE_BOOL
2381 default ""
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002382 help
Tim Bird516cbf32008-08-12 12:52:36 -07002383 Enter arguments here that should be compiled into the kernel
2384 image and used at boot time. If the boot loader provides a
2385 command line at boot time, it is appended to this string to
2386 form the full kernel command line, when the system boots.
2387
2388 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2389 change this behavior.
2390
2391 In most cases, the command line (whether built-in or provided
2392 by the boot loader) should specify the device for the root
2393 file system.
2394
2395config CMDLINE_OVERRIDE
2396 bool "Built-in command line overrides boot loader arguments"
Anders Roxell645e6462020-01-24 12:46:15 +01002397 depends on CMDLINE_BOOL && CMDLINE != ""
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002398 help
Tim Bird516cbf32008-08-12 12:52:36 -07002399 Set this option to 'Y' to have the kernel ignore the boot loader
2400 command line, and use ONLY the built-in command line.
2401
2402 This is used to work around broken boot loaders. This should
2403 be set to 'N' under normal conditions.
2404
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002405config MODIFY_LDT_SYSCALL
2406 bool "Enable the LDT (local descriptor table)" if EXPERT
2407 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002408 help
Andy Lutomirskia5b9e5a2015-07-30 14:31:34 -07002409 Linux can allow user programs to install a per-process x86
2410 Local Descriptor Table (LDT) using the modify_ldt(2) system
2411 call. This is required to run 16-bit or segmented code such as
2412 DOSEMU or some Wine programs. It is also used by some very old
2413 threading libraries.
2414
2415 Enabling this feature adds a small amount of overhead to
2416 context switches and increases the low-level kernel attack
2417 surface. Disabling it removes the modify_ldt(2) system call.
2418
2419 Saying 'N' here may make sense for embedded or server kernels.
2420
Seth Jenningsb700e7f2014-12-16 11:58:19 -06002421source "kernel/livepatch/Kconfig"
2422
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002423endmenu
2424
Michal Hocko3072e412017-09-08 16:11:39 -07002425config ARCH_HAS_ADD_PAGES
2426 def_bool y
2427 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2428
Sam Ravnborg506f1d072007-11-09 21:56:54 +01002429config ARCH_ENABLE_MEMORY_HOTPLUG
2430 def_bool y
2431 depends on X86_64 || (X86_32 && HIGHMEM)
2432
Gary Hade35551052008-10-31 10:52:03 -07002433config ARCH_ENABLE_MEMORY_HOTREMOVE
2434 def_bool y
2435 depends on MEMORY_HOTPLUG
2436
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002437config USE_PERCPU_NUMA_NODE_ID
Tejun Heo645a7912011-01-23 14:37:40 +01002438 def_bool y
Lee Schermerhorne534c7c2010-05-26 14:44:58 -07002439 depends on NUMA
2440
Kirill A. Shutemov94918462013-11-14 14:31:10 -08002441config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2442 def_bool y
2443 depends on X86_64 || X86_PAE
2444
Naoya Horiguchic177c812014-06-04 16:05:35 -07002445config ARCH_ENABLE_HUGEPAGE_MIGRATION
2446 def_bool y
2447 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2448
Naoya Horiguchi9c670ea2017-09-08 16:10:53 -07002449config ARCH_ENABLE_THP_MIGRATION
2450 def_bool y
2451 depends on X86_64 && TRANSPARENT_HUGEPAGE
2452
Bjorn Helgaasda85f862008-11-05 13:37:27 -06002453menu "Power management and ACPI options"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002454
2455config ARCH_HIBERNATION_HEADER
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002456 def_bool y
Zhimin Gu44556532018-09-21 14:27:29 +08002457 depends on HIBERNATION
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002458
2459source "kernel/power/Kconfig"
2460
2461source "drivers/acpi/Kconfig"
2462
Feng Tangefafc8b2009-08-14 15:23:29 -04002463source "drivers/sfi/Kconfig"
2464
Andi Kleena6b68072008-01-30 13:32:49 +01002465config X86_APM_BOOT
Jan Beulich6fc108a2010-04-21 15:23:44 +01002466 def_bool y
Paul Bolle282e5aa2011-11-17 11:41:31 +01002467 depends on APM
Andi Kleena6b68072008-01-30 13:32:49 +01002468
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002469menuconfig APM
2470 tristate "APM (Advanced Power Management) BIOS support"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002471 depends on X86_32 && PM_SLEEP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002472 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002473 APM is a BIOS specification for saving power using several different
2474 techniques. This is mostly useful for battery powered laptops with
2475 APM compliant BIOSes. If you say Y here, the system time will be
2476 reset after a RESUME operation, the /proc/apm device will provide
2477 battery status information, and user-space programs will receive
2478 notification of APM "events" (e.g. battery status change).
2479
2480 If you select "Y" here, you can disable actual use of the APM
2481 BIOS by passing the "apm=off" option to the kernel at boot time.
2482
2483 Note that the APM support is almost completely disabled for
2484 machines with more than one CPU.
2485
2486 In order to use APM, you will need supporting software. For location
Mauro Carvalho Chehab151f4e22019-06-13 07:10:36 -03002487 and more information, read <file:Documentation/power/apm-acpi.rst>
Michael Witten2dc98fd2011-07-08 21:11:16 +00002488 and the Battery Powered Linux mini-HOWTO, available from
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002489 <http://www.tldp.org/docs.html#howto>.
2490
2491 This driver does not spin down disk drives (see the hdparm(8)
2492 manpage ("man 8 hdparm") for that), and it doesn't turn off
2493 VESA-compliant "green" monitors.
2494
2495 This driver does not support the TI 4000M TravelMate and the ACER
2496 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2497 desktop machines also don't have compliant BIOSes, and this driver
2498 may cause those machines to panic during the boot phase.
2499
2500 Generally, if you don't have a battery in your machine, there isn't
2501 much point in using this driver and you should say N. If you get
2502 random kernel OOPSes or reboots that don't seem to be related to
2503 anything, try disabling/enabling this option (or disabling/enabling
2504 APM in your BIOS).
2505
2506 Some other things you should try when experiencing seemingly random,
2507 "weird" problems:
2508
2509 1) make sure that you have enough swap space and that it is
2510 enabled.
2511 2) pass the "no-hlt" option to the kernel
2512 3) switch on floating point emulation in the kernel and pass
2513 the "no387" option to the kernel
2514 4) pass the "floppy=nodma" option to the kernel
2515 5) pass the "mem=4M" option to the kernel (thereby disabling
2516 all but the first 4 MB of RAM)
2517 6) make sure that the CPU is not over clocked.
2518 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2519 8) disable the cache from your BIOS settings
2520 9) install a fan for the video card or exchange video RAM
2521 10) install a better fan for the CPU
2522 11) exchange RAM chips
2523 12) exchange the motherboard.
2524
2525 To compile this driver as a module, choose M here: the
2526 module will be called apm.
2527
2528if APM
2529
2530config APM_IGNORE_USER_SUSPEND
2531 bool "Ignore USER SUSPEND"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002532 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002533 This option will ignore USER SUSPEND requests. On machines with a
2534 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2535 series notebooks, it is necessary to say Y because of a BIOS bug.
2536
2537config APM_DO_ENABLE
2538 bool "Enable PM at boot time"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002539 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002540 Enable APM features at boot time. From page 36 of the APM BIOS
2541 specification: "When disabled, the APM BIOS does not automatically
2542 power manage devices, enter the Standby State, enter the Suspend
2543 State, or take power saving steps in response to CPU Idle calls."
2544 This driver will make CPU Idle calls when Linux is idle (unless this
2545 feature is turned off -- see "Do CPU IDLE calls", below). This
2546 should always save battery power, but more complicated APM features
2547 will be dependent on your BIOS implementation. You may need to turn
2548 this option off if your computer hangs at boot time when using APM
2549 support, or if it beeps continuously instead of suspending. Turn
2550 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2551 T400CDT. This is off by default since most machines do fine without
2552 this feature.
2553
2554config APM_CPU_IDLE
Len Browndd8af072013-02-09 21:10:04 -05002555 depends on CPU_IDLE
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002556 bool "Make CPU Idle calls when idle"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002557 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002558 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2559 On some machines, this can activate improved power savings, such as
2560 a slowed CPU clock rate, when the machine is idle. These idle calls
2561 are made after the idle loop has run for some length of time (e.g.,
2562 333 mS). On some machines, this will cause a hang at boot time or
2563 whenever the CPU becomes idle. (On machines with more than one CPU,
2564 this option does nothing.)
2565
2566config APM_DISPLAY_BLANK
2567 bool "Enable console blanking using APM"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002568 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002569 Enable console blanking using the APM. Some laptops can use this to
2570 turn off the LCD backlight when the screen blanker of the Linux
2571 virtual console blanks the screen. Note that this is only used by
2572 the virtual console screen blanker, and won't turn off the backlight
2573 when using the X Window system. This also doesn't have anything to
2574 do with your VESA-compliant power-saving monitor. Further, this
2575 option doesn't work for all laptops -- it might not turn off your
2576 backlight at all, or it might print a lot of errors to the console,
2577 especially if you are using gpm.
2578
2579config APM_ALLOW_INTS
2580 bool "Allow interrupts during APM BIOS calls"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002581 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002582 Normally we disable external interrupts while we are making calls to
2583 the APM BIOS as a measure to lessen the effects of a badly behaving
2584 BIOS implementation. The BIOS should reenable interrupts if it
2585 needs to. Unfortunately, some BIOSes do not -- especially those in
2586 many of the newer IBM Thinkpads. If you experience hangs when you
2587 suspend, try setting this to Y. Otherwise, say N.
2588
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002589endif # APM
2590
Dave Jonesbb0a56e2011-05-19 18:51:07 -04002591source "drivers/cpufreq/Kconfig"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002592
2593source "drivers/cpuidle/Kconfig"
2594
Andy Henroid27471fd2008-10-09 11:45:22 -07002595source "drivers/idle/Kconfig"
2596
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002597endmenu
2598
2599
2600menu "Bus options (PCI etc.)"
2601
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002602choice
2603 prompt "PCI access mode"
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002604 depends on X86_32 && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002605 default PCI_GOANY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002606 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002607 On PCI systems, the BIOS can be used to detect the PCI devices and
2608 determine their configuration. However, some old PCI motherboards
2609 have BIOS bugs and may crash if this is done. Also, some embedded
2610 PCI-based systems don't have any BIOS at all. Linux can also try to
2611 detect the PCI hardware directly without using the BIOS.
2612
2613 With this option, you can specify how Linux should detect the
2614 PCI devices. If you choose "BIOS", the BIOS will be used,
2615 if you choose "Direct", the BIOS won't be used, and if you
2616 choose "MMConfig", then PCI Express MMCONFIG will be used.
2617 If you choose "Any", the kernel will try MMCONFIG, then the
2618 direct access method and falls back to the BIOS if that doesn't
2619 work. If unsure, go with the default, which is "Any".
2620
2621config PCI_GOBIOS
2622 bool "BIOS"
2623
2624config PCI_GOMMCONFIG
2625 bool "MMConfig"
2626
2627config PCI_GODIRECT
2628 bool "Direct"
2629
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002630config PCI_GOOLPC
Daniel Drake76fb6572010-09-23 17:28:04 +01002631 bool "OLPC XO-1"
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002632 depends on OLPC
2633
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002634config PCI_GOANY
2635 bool "Any"
2636
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002637endchoice
2638
2639config PCI_BIOS
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002640 def_bool y
Ingo Molnarefefa6f2008-07-10 16:09:50 +02002641 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002642
2643# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2644config PCI_DIRECT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002645 def_bool y
Shaohua Li0aba4962011-05-27 14:59:39 +08002646 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002647
2648config PCI_MMCONFIG
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002649 bool "Support mmconfig PCI config space access" if X86_64
2650 default y
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002651 depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
Jan Kiszkab45c9f32018-03-07 08:39:16 +01002652 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002653
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002654config PCI_OLPC
Andres Salomon2bdd1b02008-06-05 14:14:41 -07002655 def_bool y
2656 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002657
Alex Nixonb5401a92010-03-18 16:31:34 -04002658config PCI_XEN
2659 def_bool y
2660 depends on PCI && XEN
2661 select SWIOTLB_XEN
2662
Jan Kiszka8364e1f2018-03-07 08:39:17 +01002663config MMCONF_FAM10H
2664 def_bool y
2665 depends on X86_64 && PCI_MMCONFIG && ACPI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002666
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002667config PCI_CNB20LE_QUIRK
David Rientjes6a108a12011-01-20 14:44:16 -08002668 bool "Read CNB20LE Host Bridge Windows" if EXPERT
Kees Cook6ea30382012-10-02 11:16:47 -07002669 depends on PCI
Ira W. Snyder3f6ea842010-04-01 11:43:30 -07002670 help
2671 Read the PCI windows out of the CNB20LE host bridge. This allows
2672 PCI hotplug to work on systems with the CNB20LE chipset which do
2673 not have ACPI.
2674
Bjorn Helgaas64a5fed2011-01-06 10:12:30 -07002675 There's no public spec for this chipset, and this functionality
2676 is known to be incomplete.
2677
2678 You should say N unless you know you need this.
2679
William Breathitt Gray3a495512016-05-27 18:08:27 -04002680config ISA_BUS
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002681 bool "ISA bus support on modern systems" if EXPERT
William Breathitt Gray3a495512016-05-27 18:08:27 -04002682 help
William Breathitt Gray17a2a122017-12-29 15:14:46 -05002683 Expose ISA bus device drivers and options available for selection and
2684 configuration. Enable this option if your target machine has an ISA
2685 bus. ISA is an older system, displaced by PCI and newer bus
2686 architectures -- if your target machine is modern, it probably does
2687 not have an ISA bus.
William Breathitt Gray3a495512016-05-27 18:08:27 -04002688
2689 If unsure, say N.
2690
David Rientjes1c00f012011-03-22 16:34:59 -07002691# x86_64 have no ISA slots, but can have ISA-style DMA.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002692config ISA_DMA_API
David Rientjes1c00f012011-03-22 16:34:59 -07002693 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2694 default y
2695 help
2696 Enables ISA-style DMA support for devices requiring such controllers.
2697 If unsure, say Y.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002698
Linus Torvalds51e68d02016-05-21 10:25:19 -07002699if X86_32
2700
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002701config ISA
2702 bool "ISA support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002703 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002704 Find out whether you have ISA slots on your motherboard. ISA is the
2705 name of a bus system, i.e. the way the CPU talks to the other stuff
2706 inside your box. Other bus systems are PCI, EISA, MicroChannel
2707 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2708 newer boards don't support it. If you have ISA, say Y, otherwise N.
2709
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002710config SCx200
2711 tristate "NatSemi SCx200 support"
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002712 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002713 This provides basic support for National Semiconductor's
2714 (now AMD's) Geode processors. The driver probes for the
2715 PCI-IDs of several on-chip devices, so its a good dependency
2716 for other scx200_* drivers.
2717
2718 If compiled as a module, the driver is named scx200.
2719
2720config SCx200HR_TIMER
2721 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
John Stultz592913e2010-07-13 17:56:20 -07002722 depends on SCx200
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002723 default y
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002724 help
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002725 This driver provides a clocksource built upon the on-chip
2726 27MHz high-resolution timer. Its also a workaround for
2727 NSC Geode SC-1100's buggy TSC, which loses time when the
2728 processor goes idle (as is done by the scheduler). The
2729 other workaround is idle=poll boot option.
2730
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002731config OLPC
2732 bool "One Laptop Per Child support"
Thomas Gleixner54008972011-02-23 09:50:15 +01002733 depends on !X86_PAE
Andres Salomon3c554942009-12-14 18:00:36 -08002734 select GPIOLIB
Thomas Gleixnerdc3119e702011-02-23 10:08:31 +01002735 select OF
Daniel Drake45bb1672011-03-13 15:10:17 +00002736 select OF_PROMTREE
Grant Likelyb4e51852011-12-16 15:50:17 -07002737 select IRQ_DOMAIN
Lubomir Rintel0c3d9312019-05-13 09:56:37 +02002738 select OLPC_EC
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002739 help
Andres Salomon3ef0e1f2008-04-29 00:59:53 -07002740 Add support for detecting the unique features of the OLPC
2741 XO hardware.
2742
Daniel Drakea3128582011-06-25 17:34:10 +01002743config OLPC_XO1_PM
2744 bool "OLPC XO-1 Power Management"
Borislav Petkovfa112cf2018-10-05 15:13:07 +02002745 depends on OLPC && MFD_CS5535=y && PM_SLEEP
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002746 help
Daniel Drake97c4cb72011-06-25 17:34:11 +01002747 Add support for poweroff and suspend of the OLPC XO-1 laptop.
Daniel Drakebf1ebf02010-10-10 10:40:32 +01002748
Daniel Drakecfee9592011-06-25 17:34:17 +01002749config OLPC_XO1_RTC
2750 bool "OLPC XO-1 Real Time Clock"
2751 depends on OLPC_XO1_PM && RTC_DRV_CMOS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002752 help
Daniel Drakecfee9592011-06-25 17:34:17 +01002753 Add support for the XO-1 real time clock, which can be used as a
2754 programmable wakeup source.
2755
Daniel Drake7feda8e2011-06-25 17:34:12 +01002756config OLPC_XO1_SCI
2757 bool "OLPC XO-1 SCI extras"
Arnd Bergmann92e830f2018-04-04 14:44:54 +02002758 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
Randy Dunlaped8e47f2012-12-18 12:22:17 -08002759 depends on INPUT=y
Daniel Draked8d01a62011-07-24 18:33:21 +01002760 select POWER_SUPPLY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002761 help
Daniel Drake7feda8e2011-06-25 17:34:12 +01002762 Add support for SCI-based features of the OLPC XO-1 laptop:
Daniel Drake7bc74b32011-06-25 17:34:14 +01002763 - EC-driven system wakeups
Daniel Drake7feda8e2011-06-25 17:34:12 +01002764 - Power button
Daniel Drake7bc74b32011-06-25 17:34:14 +01002765 - Ebook switch
Daniel Drake2cf2bae2011-06-25 17:34:15 +01002766 - Lid switch
Daniel Drakee1040ac2011-06-25 17:34:16 +01002767 - AC adapter status updates
2768 - Battery status updates
Daniel Drake7feda8e2011-06-25 17:34:12 +01002769
Daniel Drakea0f30f52011-06-25 17:34:18 +01002770config OLPC_XO15_SCI
2771 bool "OLPC XO-1.5 SCI extras"
Daniel Draked8d01a62011-07-24 18:33:21 +01002772 depends on OLPC && ACPI
2773 select POWER_SUPPLY
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002774 help
Daniel Drakea0f30f52011-06-25 17:34:18 +01002775 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2776 - EC-driven system wakeups
2777 - AC adapter status updates
2778 - Battery status updates
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002779
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002780config ALIX
2781 bool "PCEngines ALIX System Support (LED setup)"
2782 select GPIOLIB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002783 help
Ed Wildgoosed4f3e352011-09-20 14:00:12 -07002784 This option enables system support for the PCEngines ALIX.
2785 At present this just sets up LEDs for GPIO control on
2786 ALIX2/3/6 boards. However, other system specific setup should
2787 get added here.
2788
2789 Note: You must still enable the drivers for GPIO and LED support
2790 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2791
2792 Note: You have to set alix.force=1 for boards with Award BIOS.
2793
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002794config NET5501
2795 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2796 select GPIOLIB
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002797 help
Philip Prindevilleda4e3302012-03-05 15:05:15 -08002798 This option enables system support for the Soekris Engineering net5501.
2799
Philip A. Prindeville31970592012-01-14 01:45:39 -07002800config GEOS
2801 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2802 select GPIOLIB
2803 depends on DMI
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002804 help
Philip A. Prindeville31970592012-01-14 01:45:39 -07002805 This option enables system support for the Traverse Technologies GEOS.
2806
Vivien Didelot7d029122013-01-04 16:18:14 -05002807config TS5500
2808 bool "Technologic Systems TS-5500 platform support"
2809 depends on MELAN
2810 select CHECK_SIGNATURE
2811 select NEW_LEDS
2812 select LEDS_CLASS
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002813 help
Vivien Didelot7d029122013-01-04 16:18:14 -05002814 This option enables system support for the Technologic Systems TS-5500.
2815
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002816endif # X86_32
2817
Andreas Herrmann23ac4ae2010-09-17 18:03:43 +02002818config AMD_NB
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002819 def_bool y
Borislav Petkov0e152cd2010-03-12 15:43:03 +01002820 depends on CPU_SUP_AMD && PCI
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002821
David Herrmanne3263ab2013-08-02 14:05:22 +02002822config X86_SYSFB
2823 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2824 help
2825 Firmwares often provide initial graphics framebuffers so the BIOS,
2826 bootloader or kernel can show basic video-output during boot for
2827 user-guidance and debugging. Historically, x86 used the VESA BIOS
2828 Extensions and EFI-framebuffers for this, which are mostly limited
2829 to x86.
2830 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2831 framebuffers so the new generic system-framebuffer drivers can be
2832 used on x86. If the framebuffer is not compatible with the generic
Nikolas Nybye3a5dc02018-08-25 19:10:54 -04002833 modes, it is advertised as fallback platform framebuffer so legacy
David Herrmanne3263ab2013-08-02 14:05:22 +02002834 drivers like efifb, vesafb and uvesafb can pick it up.
2835 If this option is not selected, all system framebuffers are always
2836 marked as fallback platform framebuffers as usual.
2837
2838 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2839 not be able to pick up generic system framebuffers if this option
2840 is selected. You are highly encouraged to enable simplefb as
2841 replacement if you select this option. simplefb can correctly deal
2842 with generic system framebuffers. But you should still keep vesafb
2843 and others enabled as fallback if a system framebuffer is
2844 incompatible with simplefb.
2845
2846 If unsure, say Y.
2847
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002848endmenu
2849
2850
Christoph Hellwig15724972018-07-31 13:39:30 +02002851menu "Binary Emulations"
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002852
2853config IA32_EMULATION
2854 bool "IA32 Emulation"
2855 depends on X86_64
Ingo Molnar39f88912016-11-15 10:22:52 +01002856 select ARCH_WANT_OLD_COMPAT_IPC
Randy Dunlapd1603992013-06-18 12:33:40 -07002857 select BINFMT_ELF
Roland McGratha97f52e2008-01-30 13:31:55 +01002858 select COMPAT_BINFMT_ELF
Ingo Molnar39f88912016-11-15 10:22:52 +01002859 select COMPAT_OLD_SIGACTION
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002860 help
H. J. Lu5fd92e62012-02-19 10:40:03 -08002861 Include code to run legacy 32-bit programs under a
2862 64-bit kernel. You should likely turn this on, unless you're
2863 100% sure that you don't have any 32-bit programs left.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002864
2865config IA32_AOUT
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002866 tristate "IA32 a.out support"
2867 depends on IA32_EMULATION
Borislav Petkoveac61652019-03-05 15:47:51 +01002868 depends on BROKEN
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002869 help
Ingo Molnar8f9ca472009-02-05 16:21:53 +01002870 Support old a.out binaries in the 32bit emulation.
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002871
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002872config X86_X32
Kees Cook6ea30382012-10-02 11:16:47 -07002873 bool "x32 ABI for 64-bit mode"
Brian Gerst9b540502015-06-22 07:55:21 -04002874 depends on X86_64
Masahiro Yamadaa7f7f622020-06-14 01:50:22 +09002875 help
H. J. Lu5fd92e62012-02-19 10:40:03 -08002876 Include code to run binaries for the x32 native 32-bit ABI
2877 for 64-bit processors. An x32 process gets access to the
2878 full 64-bit register file and wide data path while leaving
2879 pointers at 32 bits for smaller memory footprint.
2880
2881 You will need a recent binutils (2.22 or later) with
2882 elf32_x86_64 support enabled to compile a kernel with this
2883 option set.
2884
Ingo Molnar953fee12016-11-15 10:22:52 +01002885config COMPAT_32
2886 def_bool y
2887 depends on IA32_EMULATION || X86_32
2888 select HAVE_UID16
2889 select OLD_SIGSUSPEND3
2890
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002891config COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002892 def_bool y
H. Peter Anvin0bf62762012-02-27 14:09:10 -08002893 depends on IA32_EMULATION || X86_X32
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002894
Jan Beulich3120e252012-09-10 12:41:45 +01002895if COMPAT
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002896config COMPAT_FOR_U64_ALIGNMENT
Jan Beulich3120e252012-09-10 12:41:45 +01002897 def_bool y
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002898
2899config SYSVIPC_COMPAT
Harvey Harrison3c2362e2008-01-30 13:31:03 +01002900 def_bool y
Jan Beulich3120e252012-09-10 12:41:45 +01002901 depends on SYSVIPC
Jan Beulich3120e252012-09-10 12:41:45 +01002902endif
David Howellsee009e4a02011-03-07 15:06:20 +00002903
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002904endmenu
2905
2906
Keith Packarde5beae12008-11-03 18:21:45 +01002907config HAVE_ATOMIC_IOMAP
2908 def_bool y
2909 depends on X86_32
2910
Sam Ravnborge279b6c2007-11-06 20:41:05 +01002911source "drivers/firmware/Kconfig"
2912
Avi Kivityedf88412007-12-16 11:02:48 +02002913source "arch/x86/kvm/Kconfig"
Jason A. Donenfeld5e8ebd82020-03-26 17:00:58 +09002914
2915source "arch/x86/Kconfig.assembler"