Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
[linux-2.6-block.git] / arch / x86 / Kconfig
CommitLineData
b2441318 1# SPDX-License-Identifier: GPL-2.0
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SR
2# Select 32 or 64 bit
3config 64BIT
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MY
4 bool "64-bit kernel" if "$(ARCH)" = "x86"
5 default "$(ARCH)" != "i386"
8f9ca475 6 ---help---
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SR
7 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
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11 def_bool y
12 depends on !64BIT
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IM
13 # Options that are inherently 32-bit kernel only:
14 select ARCH_WANT_IPC_PARSE_VERSION
15 select CLKSRC_I8253
16 select CLONE_BACKWARDS
17 select HAVE_AOUT
18 select HAVE_GENERIC_DMA_COHERENT
19 select MODULES_USE_ELF_REL
20 select OLD_SIGACTION
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SR
21
22config X86_64
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JB
23 def_bool y
24 depends on 64BIT
d94e0685 25 # Options that are inherently 64-bit kernel only:
e1073d1e 26 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
d94e0685
IM
27 select ARCH_SUPPORTS_INT128
28 select ARCH_USE_CMPXCHG_LOCKREF
29 select HAVE_ARCH_SOFT_DIRTY
30 select MODULES_USE_ELF_RELA
f616ab59 31 select NEED_DMA_MAP_STATE
09230cbc 32 select SWIOTLB
d94e0685 33 select X86_DEV_DMA_OPS
f8781c4a 34 select ARCH_HAS_SYSCALL_WRAPPER
1032c0ba 35
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IM
36#
37# Arch settings
38#
39# ( Note that options that are marked 'if X86_64' could in principle be
40# ported to 32-bit as well. )
41#
8d5fffb9 42config X86
3c2362e6 43 def_bool y
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IM
44 #
45 # Note: keep this list sorted alphabetically
46 #
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47 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
48 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
49 select ANON_INODES
50 select ARCH_CLOCKSOURCE_DATA
51 select ARCH_DISCARD_MEMBLOCK
c763ea26 52 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
fa5b6ec9 53 select ARCH_HAS_DEBUG_VIRTUAL
21266be9 54 select ARCH_HAS_DEVMEM_IS_ALLOWED
6471b825 55 select ARCH_HAS_ELF_RANDOMIZE
72d93104 56 select ARCH_HAS_FAST_MULTIPLIER
316d097c 57 select ARCH_HAS_FILTER_PGPROT
6974f0c4 58 select ARCH_HAS_FORTIFY_SOURCE
957e3fac 59 select ARCH_HAS_GCOV_PROFILE_ALL
5c9a8750 60 select ARCH_HAS_KCOV if X86_64
10bcc80e 61 select ARCH_HAS_MEMBARRIER_SYNC_CORE
c763ea26 62 select ARCH_HAS_PMEM_API if X86_64
3010a5ea 63 select ARCH_HAS_PTE_SPECIAL
39208aa7 64 select ARCH_HAS_REFCOUNT
0aed55af 65 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
8780356e 66 select ARCH_HAS_UACCESS_MCSAFE if X86_64
d2852a22 67 select ARCH_HAS_SET_MEMORY
6471b825 68 select ARCH_HAS_SG_CHAIN
ad21fc4f
LA
69 select ARCH_HAS_STRICT_KERNEL_RWX
70 select ARCH_HAS_STRICT_MODULE_RWX
ac1ab12a 71 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
c6d30853 72 select ARCH_HAS_UBSAN_SANITIZE_ALL
65f7d049 73 select ARCH_HAS_ZONE_DEVICE if X86_64
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IM
74 select ARCH_HAVE_NMI_SAFE_CMPXCHG
75 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
77fbbc81 76 select ARCH_MIGHT_HAVE_PC_PARPORT
5e2c18c0 77 select ARCH_MIGHT_HAVE_PC_SERIO
6471b825 78 select ARCH_SUPPORTS_ATOMIC_RMW
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IM
79 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
80 select ARCH_USE_BUILTIN_BSWAP
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81 select ARCH_USE_QUEUED_RWLOCKS
82 select ARCH_USE_QUEUED_SPINLOCKS
ce4a4e56 83 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
c763ea26 84 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
38d8b4e6 85 select ARCH_WANTS_THP_SWAP if X86_64
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86 select BUILDTIME_EXTABLE_SORT
87 select CLKEVT_I8253
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88 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
89 select CLOCKSOURCE_WATCHDOG
6471b825 90 select DCACHE_WORD_ACCESS
fec777c3 91 select DMA_DIRECT_OPS
45471cd9
LT
92 select EDAC_ATOMIC_SCRUB
93 select EDAC_SUPPORT
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IM
94 select GENERIC_CLOCKEVENTS
95 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
96 select GENERIC_CLOCKEVENTS_MIN_ADJUST
97 select GENERIC_CMOS_UPDATE
98 select GENERIC_CPU_AUTOPROBE
61dc0f55 99 select GENERIC_CPU_VULNERABILITIES
5b7c73e0 100 select GENERIC_EARLY_IOREMAP
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IM
101 select GENERIC_FIND_FIRST_BIT
102 select GENERIC_IOMAP
c7d6c9dd 103 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
0fa115da 104 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
ad7a929f 105 select GENERIC_IRQ_MIGRATION if SMP
6471b825 106 select GENERIC_IRQ_PROBE
c201c917 107 select GENERIC_IRQ_RESERVATION_MODE
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IM
108 select GENERIC_IRQ_SHOW
109 select GENERIC_PENDING_IRQ if SMP
110 select GENERIC_SMP_IDLE_THREAD
111 select GENERIC_STRNCPY_FROM_USER
112 select GENERIC_STRNLEN_USER
113 select GENERIC_TIME_VSYSCALL
7edaeb68 114 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
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IM
115 select HAVE_ACPI_APEI if ACPI
116 select HAVE_ACPI_APEI_NMI if ACPI
117 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
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118 select HAVE_ARCH_AUDITSYSCALL
119 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
120 select HAVE_ARCH_JUMP_LABEL
d17a1d97 121 select HAVE_ARCH_KASAN if X86_64
6471b825 122 select HAVE_ARCH_KGDB
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DC
123 select HAVE_ARCH_MMAP_RND_BITS if MMU
124 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
1b028f78 125 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
6471b825 126 select HAVE_ARCH_SECCOMP_FILTER
f7d83c1c 127 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
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IM
128 select HAVE_ARCH_TRACEHOOK
129 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
a00cc7d9 130 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
e37e43a4 131 select HAVE_ARCH_VMAP_STACK if X86_64
c763ea26 132 select HAVE_ARCH_WITHIN_STACK_FRAMES
2a61f474 133 select HAVE_CC_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
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IM
134 select HAVE_CMPXCHG_DOUBLE
135 select HAVE_CMPXCHG_LOCAL
136 select HAVE_CONTEXT_TRACKING if X86_64
c1bd55f9 137 select HAVE_COPY_THREAD_TLS
cf4db259 138 select HAVE_C_RECORDMCOUNT
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IM
139 select HAVE_DEBUG_KMEMLEAK
140 select HAVE_DEBUG_STACKOVERFLOW
6471b825 141 select HAVE_DMA_CONTIGUOUS
677aa9f7 142 select HAVE_DYNAMIC_FTRACE
06aeaaea 143 select HAVE_DYNAMIC_FTRACE_WITH_REGS
03f5781b 144 select HAVE_EBPF_JIT
58340a07 145 select HAVE_EFFICIENT_UNALIGNED_ACCESS
5f56a5df 146 select HAVE_EXIT_THREAD
644e0e8d 147 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
6471b825 148 select HAVE_FTRACE_MCOUNT_RECORD
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IM
149 select HAVE_FUNCTION_GRAPH_TRACER
150 select HAVE_FUNCTION_TRACER
6b90bd4b 151 select HAVE_GCC_PLUGINS
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152 select HAVE_HW_BREAKPOINT
153 select HAVE_IDE
154 select HAVE_IOREMAP_PROT
155 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
156 select HAVE_IRQ_TIME_ACCOUNTING
2e9f3bdd 157 select HAVE_KERNEL_BZIP2
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158 select HAVE_KERNEL_GZIP
159 select HAVE_KERNEL_LZ4
2e9f3bdd 160 select HAVE_KERNEL_LZMA
13510997 161 select HAVE_KERNEL_LZO
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162 select HAVE_KERNEL_XZ
163 select HAVE_KPROBES
164 select HAVE_KPROBES_ON_FTRACE
540adea3 165 select HAVE_FUNCTION_ERROR_INJECTION
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166 select HAVE_KRETPROBES
167 select HAVE_KVM
168 select HAVE_LIVEPATCH if X86_64
169 select HAVE_MEMBLOCK
170 select HAVE_MEMBLOCK_NODE_MAP
0102752e 171 select HAVE_MIXED_BREAKPOINTS_REGS
ee9f8fce 172 select HAVE_MOD_ARCH_SPECIFIC
42a0bb3f 173 select HAVE_NMI
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IM
174 select HAVE_OPROFILE
175 select HAVE_OPTPROBES
176 select HAVE_PCSPKR_PLATFORM
177 select HAVE_PERF_EVENTS
c01d4323 178 select HAVE_PERF_EVENTS_NMI
92e5aae4 179 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
c5e63197 180 select HAVE_PERF_REGS
c5ebcedb 181 select HAVE_PERF_USER_STACK_DUMP
9e52fc2b 182 select HAVE_RCU_TABLE_FREE
6471b825 183 select HAVE_REGS_AND_STACK_ACCESS_API
11af8474 184 select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
c763ea26 185 select HAVE_STACK_VALIDATION if X86_64
d6761b8f 186 select HAVE_RSEQ
6471b825 187 select HAVE_SYSCALL_TRACEPOINTS
6471b825 188 select HAVE_UNSTABLE_SCHED_CLOCK
7c68af6e 189 select HAVE_USER_RETURN_NOTIFIER
c0185808 190 select IRQ_FORCED_THREADING
86596f0a 191 select NEED_SG_DMA_LENGTH
df65c1bc 192 select PCI_LOCKLESS_CONFIG
6471b825 193 select PERF_EVENTS
3195ef59 194 select RTC_LIB
d6faca40 195 select RTC_MC146818_LIB
6471b825 196 select SPARSE_IRQ
83fe27ea 197 select SRCU
6471b825 198 select SYSCTL_EXCEPTION_TRACE
15f4eae7 199 select THREAD_INFO_IN_TASK
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IM
200 select USER_STACKTRACE_SUPPORT
201 select VIRT_TO_BUS
6471b825 202 select X86_FEATURE_NAMES if PROC_FS
7d8330a5 203
ba7e4d13 204config INSTRUCTION_DECODER
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205 def_bool y
206 depends on KPROBES || PERF_EVENTS || UPROBES
ba7e4d13 207
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LT
208config OUTPUT_FORMAT
209 string
210 default "elf32-i386" if X86_32
211 default "elf64-x86-64" if X86_64
212
73531905 213config ARCH_DEFCONFIG
b9b39bfb 214 string
73531905
SR
215 default "arch/x86/configs/i386_defconfig" if X86_32
216 default "arch/x86/configs/x86_64_defconfig" if X86_64
b9b39bfb 217
8d5fffb9 218config LOCKDEP_SUPPORT
3c2362e6 219 def_bool y
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SR
220
221config STACKTRACE_SUPPORT
3c2362e6 222 def_bool y
8d5fffb9 223
8d5fffb9 224config MMU
3c2362e6 225 def_bool y
8d5fffb9 226
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DC
227config ARCH_MMAP_RND_BITS_MIN
228 default 28 if 64BIT
229 default 8
230
231config ARCH_MMAP_RND_BITS_MAX
232 default 32 if 64BIT
233 default 16
234
235config ARCH_MMAP_RND_COMPAT_BITS_MIN
236 default 8
237
238config ARCH_MMAP_RND_COMPAT_BITS_MAX
239 default 16
240
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SR
241config SBUS
242 bool
243
244config GENERIC_ISA_DMA
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245 def_bool y
246 depends on ISA_DMA_API
8d5fffb9 247
8d5fffb9 248config GENERIC_BUG
3c2362e6 249 def_bool y
8d5fffb9 250 depends on BUG
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JB
251 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
252
253config GENERIC_BUG_RELATIVE_POINTERS
254 bool
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SR
255
256config GENERIC_HWEIGHT
3c2362e6 257 def_bool y
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SR
258
259config ARCH_MAY_HAVE_PC_FDC
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260 def_bool y
261 depends on ISA_DMA_API
8d5fffb9 262
1032c0ba 263config RWSEM_XCHGADD_ALGORITHM
3120e25e 264 def_bool y
1032c0ba 265
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SR
266config GENERIC_CALIBRATE_DELAY
267 def_bool y
268
9a0b8415 269config ARCH_HAS_CPU_RELAX
270 def_bool y
271
1b27d05b
PE
272config ARCH_HAS_CACHE_LINE_SIZE
273 def_bool y
274
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DH
275config ARCH_HAS_FILTER_PGPROT
276 def_bool y
277
dd5af90a 278config HAVE_SETUP_PER_CPU_AREA
89c9c4c5 279 def_bool y
b32ef636 280
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TH
281config NEED_PER_CPU_EMBED_FIRST_CHUNK
282 def_bool y
283
284config NEED_PER_CPU_PAGE_FIRST_CHUNK
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TH
285 def_bool y
286
801e4062
JB
287config ARCH_HIBERNATION_POSSIBLE
288 def_bool y
801e4062 289
f4cb5700
JB
290config ARCH_SUSPEND_POSSIBLE
291 def_bool y
f4cb5700 292
cfe28c5d
SC
293config ARCH_WANT_HUGE_PMD_SHARE
294 def_bool y
295
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SC
296config ARCH_WANT_GENERAL_HUGETLB
297 def_bool y
298
8d5fffb9 299config ZONE_DMA32
e0fd24a3 300 def_bool y if X86_64
8d5fffb9 301
8d5fffb9 302config AUDIT_ARCH
e0fd24a3 303 def_bool y if X86_64
8d5fffb9 304
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IM
305config ARCH_SUPPORTS_OPTIMIZED_INLINING
306 def_bool y
307
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AM
308config ARCH_SUPPORTS_DEBUG_PAGEALLOC
309 def_bool y
310
d6f2d75a
AR
311config KASAN_SHADOW_OFFSET
312 hex
313 depends on KASAN
314 default 0xdffffc0000000000
315
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SW
316config HAVE_INTEL_TXT
317 def_bool y
6ea30386 318 depends on INTEL_IOMMU && ACPI
69575d38 319
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SR
320config X86_32_SMP
321 def_bool y
322 depends on X86_32 && SMP
323
324config X86_64_SMP
325 def_bool y
326 depends on X86_64 && SMP
327
ccbeed3a
TH
328config X86_32_LAZY_GS
329 def_bool y
2bc2f688 330 depends on X86_32 && CC_STACKPROTECTOR_NONE
ccbeed3a 331
2b144498
SD
332config ARCH_SUPPORTS_UPROBES
333 def_bool y
334
d20642f0
RH
335config FIX_EARLYCON_MEM
336 def_bool y
337
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338config DYNAMIC_PHYSICAL_MASK
339 bool
340
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341config PGTABLE_LEVELS
342 int
77ef56e4 343 default 5 if X86_5LEVEL
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344 default 4 if X86_64
345 default 3 if X86_PAE
346 default 2
347
506f1d07 348source "init/Kconfig"
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MY
349
350config CC_HAS_SANE_STACKPROTECTOR
351 bool
352 default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
353 default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
354 help
355 We have to make sure stack protector is unconditionally disabled if
356 the compiler produces broken code.
357
dc52ddc0 358source "kernel/Kconfig.freezer"
8d5fffb9 359
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SR
360menu "Processor type and features"
361
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RD
362config ZONE_DMA
363 bool "DMA memory allocation support" if EXPERT
364 default y
365 help
366 DMA memory allocation support allows devices with less than 32-bit
367 addressing to allocate within the first 16MB of address space.
368 Disable if no such devices will be used.
369
370 If unsure, say Y.
371
506f1d07
SR
372config SMP
373 bool "Symmetric multi-processing support"
374 ---help---
375 This enables support for systems with more than one CPU. If you have
4a474157
RG
376 a system with only one CPU, say N. If you have a system with more
377 than one CPU, say Y.
506f1d07 378
4a474157 379 If you say N here, the kernel will run on uni- and multiprocessor
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SR
380 machines, but will use only one CPU of a multiprocessor machine. If
381 you say Y here, the kernel will run on many, but not all,
4a474157 382 uniprocessor machines. On a uniprocessor machine, the kernel
506f1d07
SR
383 will run faster if you say N here.
384
385 Note that if you say Y here and choose architecture "586" or
386 "Pentium" under "Processor family", the kernel will not work on 486
387 architectures. Similarly, multiprocessor kernels for the "PPro"
388 architecture may not work on all Pentium based boards.
389
390 People using multiprocessor machines who say Y here should also say
391 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
392 Management" code will be disabled if you say Y here.
393
395cf969 394 See also <file:Documentation/x86/i386/IO-APIC.txt>,
c9525a3f 395 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
506f1d07
SR
396 <http://www.tldp.org/docs.html#howto>.
397
398 If you don't know what to do here, say N.
399
9def39be
JT
400config X86_FEATURE_NAMES
401 bool "Processor feature human-readable names" if EMBEDDED
402 default y
403 ---help---
404 This option compiles in a table of x86 feature bits and corresponding
405 names. This is required to support /proc/cpuinfo and a few kernel
406 messages. You can disable this to save space, at the expense of
407 making those few kernel messages show numeric feature bits instead.
408
409 If in doubt, say Y.
410
06cd9a7d
YL
411config X86_X2APIC
412 bool "Support x2apic"
19e3d60d 413 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
06cd9a7d
YL
414 ---help---
415 This enables x2apic support on CPUs that have this feature.
416
417 This allows 32-bit apic IDs (so it can support very large systems),
418 and accesses the local apic via MSRs not via mmio.
419
06cd9a7d
YL
420 If you don't know what to do here, say N.
421
6695c85b 422config X86_MPPARSE
6e87f9b7 423 bool "Enable MPS table" if ACPI || SFI
7a527688 424 default y
5ab74722 425 depends on X86_LOCAL_APIC
8f9ca475 426 ---help---
6695c85b
YL
427 For old smp systems that do not have proper acpi support. Newer systems
428 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
6695c85b 429
ddd70cf9
JN
430config GOLDFISH
431 def_bool y
432 depends on X86_GOLDFISH
433
76b04384
DW
434config RETPOLINE
435 bool "Avoid speculative indirect branches in kernel"
436 default y
d5028ba8 437 select STACK_VALIDATION if HAVE_STACK_VALIDATION
76b04384
DW
438 help
439 Compile kernel with the retpoline compiler options to guard against
440 kernel-to-user data leaks by avoiding speculative indirect
441 branches. Requires a compiler with -mindirect-branch=thunk-extern
442 support for full protection. The kernel may run slower.
443
444 Without compiler support, at least indirect branches in assembler
445 code are eliminated. Since this includes the syscall entry path,
446 it is not entirely pointless.
447
f01d7d51
VS
448config INTEL_RDT
449 bool "Intel Resource Director Technology support"
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FY
450 default n
451 depends on X86 && CPU_SUP_INTEL
59fe5a77 452 select KERNFS
78e99b4a 453 help
f01d7d51
VS
454 Select to enable resource allocation and monitoring which are
455 sub-features of Intel Resource Director Technology(RDT). More
456 information about RDT can be found in the Intel x86
457 Architecture Software Developer Manual.
78e99b4a
FY
458
459 Say N if unsure.
460
8425091f 461if X86_32
a0d0bb4d
RD
462config X86_BIGSMP
463 bool "Support for big SMP systems with more than 8 CPUs"
464 depends on SMP
465 ---help---
466 This option is needed for the systems that have more than 8 CPUs
467
c5c606d9
RT
468config X86_EXTENDED_PLATFORM
469 bool "Support for extended (non-PC) x86 platforms"
470 default y
8f9ca475 471 ---help---
06ac8346
IM
472 If you disable this option then the kernel will only support
473 standard PC platforms. (which covers the vast majority of
474 systems out there.)
475
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RT
476 If you enable this option then you'll be able to select support
477 for the following (non-PC) 32 bit x86 platforms:
cb7b8023 478 Goldfish (Android emulator)
8425091f 479 AMD Elan
8425091f
RT
480 RDC R-321x SoC
481 SGI 320/540 (Visual Workstation)
83125a3a 482 STA2X11-based (e.g. Northville)
3f4110a4 483 Moorestown MID devices
06ac8346
IM
484
485 If you have one of these systems, or if you want to build a
486 generic distribution kernel, say Y here - otherwise say N.
8425091f 487endif
06ac8346 488
8425091f
RT
489if X86_64
490config X86_EXTENDED_PLATFORM
491 bool "Support for extended (non-PC) x86 platforms"
492 default y
493 ---help---
494 If you disable this option then the kernel will only support
495 standard PC platforms. (which covers the vast majority of
496 systems out there.)
497
498 If you enable this option then you'll be able to select support
499 for the following (non-PC) 64 bit x86 platforms:
44b111b5 500 Numascale NumaChip
8425091f
RT
501 ScaleMP vSMP
502 SGI Ultraviolet
503
504 If you have one of these systems, or if you want to build a
505 generic distribution kernel, say Y here - otherwise say N.
506endif
c5c606d9
RT
507# This is an alphabetically sorted list of 64 bit extended platforms
508# Please maintain the alphabetic order if and when there are additions
44b111b5
SP
509config X86_NUMACHIP
510 bool "Numascale NumaChip"
511 depends on X86_64
512 depends on X86_EXTENDED_PLATFORM
513 depends on NUMA
514 depends on SMP
515 depends on X86_X2APIC
f9726bfd 516 depends on PCI_MMCONFIG
44b111b5
SP
517 ---help---
518 Adds support for Numascale NumaChip large-SMP systems. Needed to
519 enable more than ~168 cores.
520 If you don't have one of these, you should say N here.
506f1d07 521
c5c606d9
RT
522config X86_VSMP
523 bool "ScaleMP vSMP"
6276a074 524 select HYPERVISOR_GUEST
c5c606d9
RT
525 select PARAVIRT
526 depends on X86_64 && PCI
527 depends on X86_EXTENDED_PLATFORM
ead91d4b 528 depends on SMP
8f9ca475 529 ---help---
c5c606d9
RT
530 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
531 supposed to run on these EM64T-based machines. Only choose this option
532 if you have one of these machines.
5e3a77e9 533
03b48632
NP
534config X86_UV
535 bool "SGI Ultraviolet"
536 depends on X86_64
c5c606d9 537 depends on X86_EXTENDED_PLATFORM
54c28d29 538 depends on NUMA
1ecb4ae5 539 depends on EFI
9d6c26e7 540 depends on X86_X2APIC
1222e564 541 depends on PCI
8f9ca475 542 ---help---
03b48632
NP
543 This option is needed in order to support SGI Ultraviolet systems.
544 If you don't have one of these, you should say N here.
545
c5c606d9
RT
546# Following is an alphabetically sorted list of 32 bit extended platforms
547# Please maintain the alphabetic order if and when there are additions
506f1d07 548
ddd70cf9
JN
549config X86_GOLDFISH
550 bool "Goldfish (Virtual Platform)"
cb7b8023 551 depends on X86_EXTENDED_PLATFORM
ddd70cf9
JN
552 ---help---
553 Enable support for the Goldfish virtual platform used primarily
554 for Android development. Unless you are building for the Android
555 Goldfish emulator say N here.
556
c751e17b
TG
557config X86_INTEL_CE
558 bool "CE4100 TV platform"
559 depends on PCI
560 depends on PCI_GODIRECT
6084a6e2 561 depends on X86_IO_APIC
c751e17b
TG
562 depends on X86_32
563 depends on X86_EXTENDED_PLATFORM
37bc9f50 564 select X86_REBOOTFIXUPS
da6b737b
SAS
565 select OF
566 select OF_EARLY_FLATTREE
c751e17b
TG
567 ---help---
568 Select for the Intel CE media processor (CE4100) SOC.
569 This option compiles in support for the CE4100 SOC for settop
570 boxes and media devices.
571
4cb9b00f 572config X86_INTEL_MID
43605ef1 573 bool "Intel MID platform support"
43605ef1 574 depends on X86_EXTENDED_PLATFORM
edc6bc78 575 depends on X86_PLATFORM_DEVICES
1ea7c673 576 depends on PCI
3fda5bb4 577 depends on X86_64 || (PCI_GOANY && X86_32)
1ea7c673 578 depends on X86_IO_APIC
7c9c3a1e 579 select SFI
4cb9b00f 580 select I2C
7c9c3a1e 581 select DW_APB_TIMER
1ea7c673 582 select APB_TIMER
1ea7c673 583 select INTEL_SCU_IPC
15a713df 584 select MFD_INTEL_MSIC
1ea7c673 585 ---help---
4cb9b00f
DC
586 Select to build a kernel capable of supporting Intel MID (Mobile
587 Internet Device) platform systems which do not have the PCI legacy
588 interfaces. If you are building for a PC class system say N here.
1ea7c673 589
4cb9b00f
DC
590 Intel MID platforms are based on an Intel processor and chipset which
591 consume less power than most of the x86 derivatives.
43605ef1 592
8bbc2a13
BD
593config X86_INTEL_QUARK
594 bool "Intel Quark platform support"
595 depends on X86_32
596 depends on X86_EXTENDED_PLATFORM
597 depends on X86_PLATFORM_DEVICES
598 depends on X86_TSC
599 depends on PCI
600 depends on PCI_GOANY
601 depends on X86_IO_APIC
602 select IOSF_MBI
603 select INTEL_IMR
9ab6eb51 604 select COMMON_CLK
8bbc2a13
BD
605 ---help---
606 Select to include support for Quark X1000 SoC.
607 Say Y here if you have a Quark based system such as the Arduino
608 compatible Intel Galileo.
609
3d48aab1
MW
610config X86_INTEL_LPSS
611 bool "Intel Low Power Subsystem Support"
eebb3e8d 612 depends on X86 && ACPI
3d48aab1 613 select COMMON_CLK
0f531431 614 select PINCTRL
eebb3e8d 615 select IOSF_MBI
3d48aab1
MW
616 ---help---
617 Select to build support for Intel Low Power Subsystem such as
618 found on Intel Lynxpoint PCH. Selecting this option enables
0f531431
MN
619 things like clock tree (common clock framework) and pincontrol
620 which are needed by the LPSS peripheral drivers.
3d48aab1 621
92082a88
KX
622config X86_AMD_PLATFORM_DEVICE
623 bool "AMD ACPI2Platform devices support"
624 depends on ACPI
625 select COMMON_CLK
626 select PINCTRL
627 ---help---
628 Select to interpret AMD specific ACPI device to platform device
629 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
630 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
631 implemented under PINCTRL subsystem.
632
ced3ce76
DB
633config IOSF_MBI
634 tristate "Intel SoC IOSF Sideband support for SoC platforms"
635 depends on PCI
636 ---help---
637 This option enables sideband register access support for Intel SoC
638 platforms. On these platforms the IOSF sideband is used in lieu of
639 MSR's for some register accesses, mostly but not limited to thermal
640 and power. Drivers may query the availability of this device to
641 determine if they need the sideband in order to work on these
642 platforms. The sideband is available on the following SoC products.
643 This list is not meant to be exclusive.
644 - BayTrail
645 - Braswell
646 - Quark
647
648 You should say Y if you are running a kernel on one of these SoC's.
649
ed2226bd
DB
650config IOSF_MBI_DEBUG
651 bool "Enable IOSF sideband access through debugfs"
652 depends on IOSF_MBI && DEBUG_FS
653 ---help---
654 Select this option to expose the IOSF sideband access registers (MCR,
655 MDR, MCRX) through debugfs to write and read register information from
656 different units on the SoC. This is most useful for obtaining device
657 state information for debug and analysis. As this is a general access
658 mechanism, users of this option would have specific knowledge of the
659 device they want to access.
660
661 If you don't require the option or are in doubt, say N.
662
c5c606d9
RT
663config X86_RDC321X
664 bool "RDC R-321x SoC"
506f1d07 665 depends on X86_32
c5c606d9
RT
666 depends on X86_EXTENDED_PLATFORM
667 select M486
668 select X86_REBOOTFIXUPS
669 ---help---
670 This option is needed for RDC R-321x system-on-chip, also known
671 as R-8610-(G).
672 If you don't have one of these chips, you should say N here.
673
e0c7ae37 674config X86_32_NON_STANDARD
9c398017
IM
675 bool "Support non-standard 32-bit SMP architectures"
676 depends on X86_32 && SMP
c5c606d9 677 depends on X86_EXTENDED_PLATFORM
8f9ca475 678 ---help---
b5660ba7
PA
679 This option compiles in the bigsmp and STA2X11 default
680 subarchitectures. It is intended for a generic binary
681 kernel. If you select them all, kernel will probe it one by
682 one and will fallback to default.
d49c4288 683
c5c606d9 684# Alphabetically sorted list of Non standard 32 bit platforms
d49c4288 685
d949f36f 686config X86_SUPPORTS_MEMORY_FAILURE
6fc108a0 687 def_bool y
d949f36f
LT
688 # MCE code calls memory_failure():
689 depends on X86_MCE
690 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
d949f36f
LT
691 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
692 depends on X86_64 || !SPARSEMEM
693 select ARCH_SUPPORTS_MEMORY_FAILURE
d949f36f 694
83125a3a
AR
695config STA2X11
696 bool "STA2X11 Companion Chip Support"
697 depends on X86_32_NON_STANDARD && PCI
b6e05477 698 select ARCH_HAS_PHYS_TO_DMA
83125a3a
AR
699 select X86_DEV_DMA_OPS
700 select X86_DMA_REMAP
701 select SWIOTLB
702 select MFD_STA2X11
0145071b 703 select GPIOLIB
83125a3a
AR
704 default n
705 ---help---
706 This adds support for boards based on the STA2X11 IO-Hub,
707 a.k.a. "ConneXt". The chip is used in place of the standard
708 PC chipset, so all "standard" peripherals are missing. If this
709 option is selected the kernel will still be able to boot on
710 standard PC machines.
711
82148d1d
S
712config X86_32_IRIS
713 tristate "Eurobraille/Iris poweroff module"
714 depends on X86_32
715 ---help---
716 The Iris machines from EuroBraille do not have APM or ACPI support
717 to shut themselves down properly. A special I/O sequence is
718 needed to do so, which is what this module does at
719 kernel shutdown.
720
721 This is only for Iris machines from EuroBraille.
722
723 If unused, say N.
724
ae1e9130 725config SCHED_OMIT_FRAME_POINTER
3c2362e6
HH
726 def_bool y
727 prompt "Single-depth WCHAN output"
a87d0914 728 depends on X86
8f9ca475 729 ---help---
506f1d07
SR
730 Calculate simpler /proc/<PID>/wchan values. If this option
731 is disabled then wchan values will recurse back to the
732 caller function. This provides more accurate wchan values,
733 at the expense of slightly more scheduling overhead.
734
735 If in doubt, say "Y".
736
6276a074
BP
737menuconfig HYPERVISOR_GUEST
738 bool "Linux guest support"
8f9ca475 739 ---help---
6276a074
BP
740 Say Y here to enable options for running Linux under various hyper-
741 visors. This option enables basic hypervisor detection and platform
742 setup.
506f1d07 743
6276a074
BP
744 If you say N, all options in this submenu will be skipped and
745 disabled, and Linux guest support won't be built in.
506f1d07 746
6276a074 747if HYPERVISOR_GUEST
506f1d07 748
e61bd94a
EPH
749config PARAVIRT
750 bool "Enable paravirtualization code"
8f9ca475 751 ---help---
e61bd94a
EPH
752 This changes the kernel so it can modify itself when it is run
753 under a hypervisor, potentially improving performance significantly
754 over full virtualization. However, when run without a hypervisor
755 the kernel is theoretically slower and slightly larger.
756
6276a074
BP
757config PARAVIRT_DEBUG
758 bool "paravirt-ops debugging"
759 depends on PARAVIRT && DEBUG_KERNEL
760 ---help---
761 Enable to debug paravirt_ops internals. Specifically, BUG if
762 a paravirt_op is missing when it is called.
763
b4ecc126
JF
764config PARAVIRT_SPINLOCKS
765 bool "Paravirtualization layer for spinlocks"
6ea30386 766 depends on PARAVIRT && SMP
b4ecc126
JF
767 ---help---
768 Paravirtualized spinlocks allow a pvops backend to replace the
769 spinlock implementation with something virtualization-friendly
770 (for example, block the virtual CPU rather than spinning).
771
4c4e4f61
R
772 It has a minimal impact on native kernels and gives a nice performance
773 benefit on paravirtualized KVM / Xen kernels.
b4ecc126 774
4c4e4f61 775 If you are unsure how to answer this question, answer Y.
b4ecc126 776
45e898b7
WL
777config QUEUED_LOCK_STAT
778 bool "Paravirt queued spinlock statistics"
cfd8983f 779 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
45e898b7
WL
780 ---help---
781 Enable the collection of statistical data on the slowpath
782 behavior of paravirtualized queued spinlocks and report
783 them on debugfs.
784
6276a074 785source "arch/x86/xen/Kconfig"
7af192c9 786
6276a074
BP
787config KVM_GUEST
788 bool "KVM Guest support (including kvmclock)"
789 depends on PARAVIRT
790 select PARAVIRT_CLOCK
791 default y
8f9ca475 792 ---help---
6276a074
BP
793 This option enables various optimizations for running under the KVM
794 hypervisor. It includes a paravirtualized clock, so that instead
795 of relying on a PIT (or probably other) emulation by the
796 underlying device model, the host provides the guest with
797 timing infrastructure such as time of day, and system time
506f1d07 798
1e20eb85
SV
799config KVM_DEBUG_FS
800 bool "Enable debug information for KVM Guests in debugfs"
801 depends on KVM_GUEST && DEBUG_FS
802 default n
803 ---help---
804 This option enables collection of various statistics for KVM guest.
805 Statistics are displayed in debugfs filesystem. Enabling this option
806 may incur significant overhead.
807
6276a074
BP
808config PARAVIRT_TIME_ACCOUNTING
809 bool "Paravirtual steal time accounting"
810 depends on PARAVIRT
811 default n
8f9ca475 812 ---help---
6276a074
BP
813 Select this option to enable fine granularity task steal time
814 accounting. Time spent executing other tasks in parallel with
815 the current vCPU is discounted from the vCPU power. To account for
816 that, there can be a small performance impact.
817
818 If in doubt, say N here.
819
820config PARAVIRT_CLOCK
821 bool
97349135 822
4a362601
JK
823config JAILHOUSE_GUEST
824 bool "Jailhouse non-root cell support"
abde587b 825 depends on X86_64 && PCI
87e65d05 826 select X86_PM_TIMER
4a362601
JK
827 ---help---
828 This option allows to run Linux as guest in a Jailhouse non-root
829 cell. You can leave this option disabled if you only want to start
830 Jailhouse and run Linux afterwards in the root cell.
831
6276a074 832endif #HYPERVISOR_GUEST
97349135 833
08677214 834config NO_BOOTMEM
774ea0bc 835 def_bool y
08677214 836
506f1d07
SR
837source "arch/x86/Kconfig.cpu"
838
839config HPET_TIMER
3c2362e6 840 def_bool X86_64
506f1d07 841 prompt "HPET Timer Support" if X86_32
8f9ca475
IM
842 ---help---
843 Use the IA-PC HPET (High Precision Event Timer) to manage
844 time in preference to the PIT and RTC, if a HPET is
845 present.
846 HPET is the next generation timer replacing legacy 8254s.
847 The HPET provides a stable time base on SMP
848 systems, unlike the TSC, but it is more expensive to access,
4e7f9df2
MT
849 as it is off-chip. The interface used is documented
850 in the HPET spec, revision 1.
506f1d07 851
8f9ca475
IM
852 You can safely choose Y here. However, HPET will only be
853 activated if the platform and the BIOS support this feature.
854 Otherwise the 8254 will be used for timing services.
506f1d07 855
8f9ca475 856 Choose N to continue using the legacy 8254 timer.
506f1d07
SR
857
858config HPET_EMULATE_RTC
3c2362e6 859 def_bool y
9d8af78b 860 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
506f1d07 861
bb24c471 862config APB_TIMER
933b9463
AC
863 def_bool y if X86_INTEL_MID
864 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
06c3df49 865 select DW_APB_TIMER
a0c3832a 866 depends on X86_INTEL_MID && SFI
bb24c471
JP
867 help
868 APB timer is the replacement for 8254, HPET on X86 MID platforms.
869 The APBT provides a stable time base on SMP
870 systems, unlike the TSC, but it is more expensive to access,
871 as it is off-chip. APB timers are always running regardless of CPU
872 C states, they are used as per CPU clockevent device when possible.
873
6a108a14 874# Mark as expert because too many people got it wrong.
506f1d07 875# The code disables itself when not needed.
7ae9392c
TP
876config DMI
877 default y
cf074402 878 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
6a108a14 879 bool "Enable DMI scanning" if EXPERT
8f9ca475 880 ---help---
7ae9392c
TP
881 Enabled scanning of DMI to identify machine quirks. Say Y
882 here unless you have verified that your setup is not
883 affected by entries in the DMI blacklist. Required by PNP
884 BIOS code.
885
506f1d07 886config GART_IOMMU
38901f1c 887 bool "Old AMD GART IOMMU support"
a4ce5a48 888 select IOMMU_HELPER
506f1d07 889 select SWIOTLB
23ac4ae8 890 depends on X86_64 && PCI && AMD_NB
8f9ca475 891 ---help---
ced3c42c
IM
892 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
893 GART based hardware IOMMUs.
894
895 The GART supports full DMA access for devices with 32-bit access
896 limitations, on systems with more than 3 GB. This is usually needed
897 for USB, sound, many IDE/SATA chipsets and some other devices.
898
899 Newer systems typically have a modern AMD IOMMU, supported via
900 the CONFIG_AMD_IOMMU=y config option.
901
902 In normal configurations this driver is only active when needed:
903 there's more than 3 GB of memory and the system contains a
904 32-bit limited device.
905
906 If unsure, say Y.
506f1d07
SR
907
908config CALGARY_IOMMU
909 bool "IBM Calgary IOMMU support"
a4ce5a48 910 select IOMMU_HELPER
506f1d07 911 select SWIOTLB
6ea30386 912 depends on X86_64 && PCI
8f9ca475 913 ---help---
506f1d07
SR
914 Support for hardware IOMMUs in IBM's xSeries x366 and x460
915 systems. Needed to run systems with more than 3GB of memory
916 properly with 32-bit PCI devices that do not support DAC
917 (Double Address Cycle). Calgary also supports bus level
918 isolation, where all DMAs pass through the IOMMU. This
919 prevents them from going anywhere except their intended
920 destination. This catches hard-to-find kernel bugs and
921 mis-behaving drivers and devices that do not use the DMA-API
922 properly to set up their DMA buffers. The IOMMU can be
923 turned off at boot time with the iommu=off parameter.
924 Normally the kernel will make the right choice by itself.
925 If unsure, say Y.
926
927config CALGARY_IOMMU_ENABLED_BY_DEFAULT
3c2362e6
HH
928 def_bool y
929 prompt "Should Calgary be enabled by default?"
506f1d07 930 depends on CALGARY_IOMMU
8f9ca475 931 ---help---
506f1d07
SR
932 Should Calgary be enabled by default? if you choose 'y', Calgary
933 will be used (if it exists). If you choose 'n', Calgary will not be
934 used even if it exists. If you choose 'n' and would like to use
935 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
936 If unsure, say Y.
506f1d07 937
1184dc2f 938config MAXSMP
ddb0c5a6 939 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
6ea30386 940 depends on X86_64 && SMP && DEBUG_KERNEL
36f5101a 941 select CPUMASK_OFFSTACK
8f9ca475 942 ---help---
ddb0c5a6 943 Enable maximum number of CPUS and NUMA Nodes for this architecture.
1184dc2f 944 If unsure, say N.
506f1d07 945
aec6487e
IM
946#
947# The maximum number of CPUs supported:
948#
949# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
950# and which can be configured interactively in the
951# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
952#
953# The ranges are different on 32-bit and 64-bit kernels, depending on
954# hardware capabilities and scalability features of the kernel.
955#
956# ( If MAXSMP is enabled we just use the highest possible value and disable
957# interactive configuration. )
958#
959
960config NR_CPUS_RANGE_BEGIN
a0d0bb4d 961 int
aec6487e
IM
962 default NR_CPUS_RANGE_END if MAXSMP
963 default 1 if !SMP
964 default 2
a0d0bb4d 965
aec6487e 966config NR_CPUS_RANGE_END
a0d0bb4d 967 int
aec6487e
IM
968 depends on X86_32
969 default 64 if SMP && X86_BIGSMP
970 default 8 if SMP && !X86_BIGSMP
971 default 1 if !SMP
a0d0bb4d 972
aec6487e 973config NR_CPUS_RANGE_END
a0d0bb4d 974 int
aec6487e
IM
975 depends on X86_64
976 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
977 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
978 default 1 if !SMP
a0d0bb4d 979
aec6487e 980config NR_CPUS_DEFAULT
a0d0bb4d
RD
981 int
982 depends on X86_32
aec6487e
IM
983 default 32 if X86_BIGSMP
984 default 8 if SMP
985 default 1 if !SMP
a0d0bb4d 986
aec6487e 987config NR_CPUS_DEFAULT
a0d0bb4d
RD
988 int
989 depends on X86_64
aec6487e
IM
990 default 8192 if MAXSMP
991 default 64 if SMP
992 default 1 if !SMP
a0d0bb4d 993
506f1d07 994config NR_CPUS
36f5101a 995 int "Maximum number of CPUs" if SMP && !MAXSMP
aec6487e
IM
996 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
997 default NR_CPUS_DEFAULT
8f9ca475 998 ---help---
506f1d07 999 This allows you to specify the maximum number of CPUs which this
bb61ccc7 1000 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
cad14bb9 1001 supported value is 8192, otherwise the maximum value is 512. The
506f1d07
SR
1002 minimum value which makes sense is 2.
1003
aec6487e
IM
1004 This is purely to save memory: each supported CPU adds about 8KB
1005 to the kernel image.
506f1d07
SR
1006
1007config SCHED_SMT
1008 bool "SMT (Hyperthreading) scheduler support"
c8e56d20 1009 depends on SMP
8f9ca475 1010 ---help---
506f1d07
SR
1011 SMT scheduler support improves the CPU scheduler's decision making
1012 when dealing with Intel Pentium 4 chips with HyperThreading at a
1013 cost of slightly increased overhead in some places. If unsure say
1014 N here.
1015
1016config SCHED_MC
3c2362e6
HH
1017 def_bool y
1018 prompt "Multi-core scheduler support"
c8e56d20 1019 depends on SMP
8f9ca475 1020 ---help---
506f1d07
SR
1021 Multi-core scheduler support improves the CPU scheduler's decision
1022 making when dealing with multi-core CPU chips at a cost of slightly
1023 increased overhead in some places. If unsure say N here.
1024
de966cf4
TC
1025config SCHED_MC_PRIO
1026 bool "CPU core priorities scheduler support"
0a21fc12
IM
1027 depends on SCHED_MC && CPU_SUP_INTEL
1028 select X86_INTEL_PSTATE
1029 select CPU_FREQ
de966cf4 1030 default y
5e76b2ab 1031 ---help---
0a21fc12
IM
1032 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1033 core ordering determined at manufacturing time, which allows
1034 certain cores to reach higher turbo frequencies (when running
1035 single threaded workloads) than others.
de966cf4 1036
0a21fc12
IM
1037 Enabling this kernel feature teaches the scheduler about
1038 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1039 scheduler's CPU selection logic accordingly, so that higher
1040 overall system performance can be achieved.
de966cf4 1041
0a21fc12 1042 This feature will have no effect on CPUs without this feature.
de966cf4 1043
0a21fc12 1044 If unsure say Y here.
5e76b2ab 1045
506f1d07
SR
1046source "kernel/Kconfig.preempt"
1047
30b8b006
TG
1048config UP_LATE_INIT
1049 def_bool y
ba360f88 1050 depends on !SMP && X86_LOCAL_APIC
30b8b006 1051
506f1d07 1052config X86_UP_APIC
50849eef
JB
1053 bool "Local APIC support on uniprocessors" if !PCI_MSI
1054 default PCI_MSI
38a1dfda 1055 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
8f9ca475 1056 ---help---
506f1d07
SR
1057 A local APIC (Advanced Programmable Interrupt Controller) is an
1058 integrated interrupt controller in the CPU. If you have a single-CPU
1059 system which has a processor with a local APIC, you can say Y here to
1060 enable and use it. If you say Y here even though your machine doesn't
1061 have a local APIC, then the kernel will still run with no slowdown at
1062 all. The local APIC supports CPU-generated self-interrupts (timer,
1063 performance counters), and the NMI watchdog which detects hard
1064 lockups.
1065
1066config X86_UP_IOAPIC
1067 bool "IO-APIC support on uniprocessors"
1068 depends on X86_UP_APIC
8f9ca475 1069 ---help---
506f1d07
SR
1070 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1071 SMP-capable replacement for PC-style interrupt controllers. Most
1072 SMP systems and many recent uniprocessor systems have one.
1073
1074 If you have a single-CPU system with an IO-APIC, you can say Y here
1075 to use it. If you say Y here even though your machine doesn't have
1076 an IO-APIC, then the kernel will still run with no slowdown at all.
1077
1078config X86_LOCAL_APIC
3c2362e6 1079 def_bool y
0dbc6078 1080 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
b5dc8e6c 1081 select IRQ_DOMAIN_HIERARCHY
52f518a3 1082 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
506f1d07
SR
1083
1084config X86_IO_APIC
b1da1e71
JB
1085 def_bool y
1086 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
506f1d07 1087
41b9eb26
SA
1088config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1089 bool "Reroute for broken boot IRQs"
41b9eb26 1090 depends on X86_IO_APIC
8f9ca475 1091 ---help---
41b9eb26
SA
1092 This option enables a workaround that fixes a source of
1093 spurious interrupts. This is recommended when threaded
1094 interrupt handling is used on systems where the generation of
1095 superfluous "boot interrupts" cannot be disabled.
1096
1097 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1098 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1099 kernel does during interrupt handling). On chipsets where this
1100 boot IRQ generation cannot be disabled, this workaround keeps
1101 the original IRQ line masked so that only the equivalent "boot
1102 IRQ" is delivered to the CPUs. The workaround also tells the
1103 kernel to set up the IRQ handler on the boot IRQ line. In this
1104 way only one interrupt is delivered to the kernel. Otherwise
1105 the spurious second interrupt may cause the kernel to bring
1106 down (vital) interrupt lines.
1107
1108 Only affects "broken" chipsets. Interrupt sharing may be
1109 increased on these systems.
1110
506f1d07 1111config X86_MCE
bab9bc65 1112 bool "Machine Check / overheating reporting"
648ed940 1113 select GENERIC_ALLOCATOR
e57dbaf7 1114 default y
506f1d07 1115 ---help---
bab9bc65
AK
1116 Machine Check support allows the processor to notify the
1117 kernel if it detects a problem (e.g. overheating, data corruption).
506f1d07 1118 The action the kernel takes depends on the severity of the problem,
bab9bc65 1119 ranging from warning messages to halting the machine.
4efc0670 1120
5de97c9f
TL
1121config X86_MCELOG_LEGACY
1122 bool "Support for deprecated /dev/mcelog character device"
1123 depends on X86_MCE
1124 ---help---
1125 Enable support for /dev/mcelog which is needed by the old mcelog
1126 userspace logging daemon. Consider switching to the new generation
1127 rasdaemon solution.
1128
506f1d07 1129config X86_MCE_INTEL
3c2362e6
HH
1130 def_bool y
1131 prompt "Intel MCE features"
c1ebf835 1132 depends on X86_MCE && X86_LOCAL_APIC
8f9ca475 1133 ---help---
506f1d07
SR
1134 Additional support for intel specific MCE features such as
1135 the thermal monitor.
1136
1137config X86_MCE_AMD
3c2362e6
HH
1138 def_bool y
1139 prompt "AMD MCE features"
f5382de9 1140 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
8f9ca475 1141 ---help---
506f1d07
SR
1142 Additional support for AMD specific MCE features such as
1143 the DRAM Error Threshold.
1144
4efc0670 1145config X86_ANCIENT_MCE
6fc108a0 1146 bool "Support for old Pentium 5 / WinChip machine checks"
c31d9633 1147 depends on X86_32 && X86_MCE
cd13adcc
HS
1148 ---help---
1149 Include support for machine check handling on old Pentium 5 or WinChip
5065a706 1150 systems. These typically need to be enabled explicitly on the command
cd13adcc 1151 line.
4efc0670 1152
b2762686
AK
1153config X86_MCE_THRESHOLD
1154 depends on X86_MCE_AMD || X86_MCE_INTEL
6fc108a0 1155 def_bool y
b2762686 1156
ea149b36 1157config X86_MCE_INJECT
bc8e80d5 1158 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
ea149b36
AK
1159 tristate "Machine check injector support"
1160 ---help---
1161 Provide support for injecting machine checks for testing purposes.
1162 If you don't know what a machine check is and you don't do kernel
1163 QA it is safe to say n.
1164
4efc0670
AK
1165config X86_THERMAL_VECTOR
1166 def_bool y
5bb38adc 1167 depends on X86_MCE_INTEL
4efc0670 1168
07dc900e 1169source "arch/x86/events/Kconfig"
e633c65a 1170
5aef51c3 1171config X86_LEGACY_VM86
1e642812 1172 bool "Legacy VM86 support"
5aef51c3 1173 default n
506f1d07 1174 depends on X86_32
8f9ca475 1175 ---help---
5aef51c3
AL
1176 This option allows user programs to put the CPU into V8086
1177 mode, which is an 80286-era approximation of 16-bit real mode.
1178
1179 Some very old versions of X and/or vbetool require this option
1180 for user mode setting. Similarly, DOSEMU will use it if
1181 available to accelerate real mode DOS programs. However, any
1182 recent version of DOSEMU, X, or vbetool should be fully
1183 functional even without kernel VM86 support, as they will all
1e642812
IM
1184 fall back to software emulation. Nevertheless, if you are using
1185 a 16-bit DOS program where 16-bit performance matters, vm86
1186 mode might be faster than emulation and you might want to
1187 enable this option.
5aef51c3 1188
1e642812
IM
1189 Note that any app that works on a 64-bit kernel is unlikely to
1190 need this option, as 64-bit kernels don't, and can't, support
1191 V8086 mode. This option is also unrelated to 16-bit protected
1192 mode and is not needed to run most 16-bit programs under Wine.
5aef51c3 1193
1e642812
IM
1194 Enabling this option increases the complexity of the kernel
1195 and slows down exception handling a tiny bit.
5aef51c3 1196
1e642812 1197 If unsure, say N here.
5aef51c3
AL
1198
1199config VM86
1200 bool
1201 default X86_LEGACY_VM86
34273f41
PA
1202
1203config X86_16BIT
1204 bool "Enable support for 16-bit segments" if EXPERT
1205 default y
a5b9e5a2 1206 depends on MODIFY_LDT_SYSCALL
34273f41
PA
1207 ---help---
1208 This option is required by programs like Wine to run 16-bit
1209 protected mode legacy code on x86 processors. Disabling
1210 this option saves about 300 bytes on i386, or around 6K text
1211 plus 16K runtime memory on x86-64,
1212
1213config X86_ESPFIX32
1214 def_bool y
1215 depends on X86_16BIT && X86_32
506f1d07 1216
197725de
PA
1217config X86_ESPFIX64
1218 def_bool y
34273f41 1219 depends on X86_16BIT && X86_64
506f1d07 1220
1ad83c85
AL
1221config X86_VSYSCALL_EMULATION
1222 bool "Enable vsyscall emulation" if EXPERT
1223 default y
1224 depends on X86_64
1225 ---help---
1226 This enables emulation of the legacy vsyscall page. Disabling
1227 it is roughly equivalent to booting with vsyscall=none, except
1228 that it will also disable the helpful warning if a program
1229 tries to use a vsyscall. With this option set to N, offending
1230 programs will just segfault, citing addresses of the form
1231 0xffffffffff600?00.
1232
1233 This option is required by many programs built before 2013, and
1234 care should be used even with newer programs if set to N.
1235
1236 Disabling this option saves about 7K of kernel size and
1237 possibly 4K of additional runtime pagetable memory.
1238
506f1d07
SR
1239config TOSHIBA
1240 tristate "Toshiba Laptop support"
1241 depends on X86_32
1242 ---help---
1243 This adds a driver to safely access the System Management Mode of
1244 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1245 not work on models with a Phoenix BIOS. The System Management Mode
1246 is used to set the BIOS and power saving options on Toshiba portables.
1247
1248 For information on utilities to make use of this driver see the
1249 Toshiba Linux utilities web site at:
1250 <http://www.buzzard.org.uk/toshiba/>.
1251
1252 Say Y if you intend to run this kernel on a Toshiba portable.
1253 Say N otherwise.
1254
1255config I8K
039ae585 1256 tristate "Dell i8k legacy laptop support"
949a9d70 1257 select HWMON
039ae585 1258 select SENSORS_DELL_SMM
506f1d07 1259 ---help---
039ae585
PR
1260 This option enables legacy /proc/i8k userspace interface in hwmon
1261 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1262 temperature and allows controlling fan speeds of Dell laptops via
1263 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1264 it reports also power and hotkey status. For fan speed control is
1265 needed userspace package i8kutils.
1266
1267 Say Y if you intend to run this kernel on old Dell laptops or want to
1268 use userspace package i8kutils.
506f1d07
SR
1269 Say N otherwise.
1270
1271config X86_REBOOTFIXUPS
9ba16087
JB
1272 bool "Enable X86 board specific fixups for reboot"
1273 depends on X86_32
506f1d07
SR
1274 ---help---
1275 This enables chipset and/or board specific fixups to be done
1276 in order to get reboot to work correctly. This is only needed on
1277 some combinations of hardware and BIOS. The symptom, for which
1278 this config is intended, is when reboot ends with a stalled/hung
1279 system.
1280
1281 Currently, the only fixup is for the Geode machines using
5e3a77e9 1282 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
506f1d07
SR
1283
1284 Say Y if you want to enable the fixup. Currently, it's safe to
1285 enable this option even if you don't need it.
1286 Say N otherwise.
1287
1288config MICROCODE
9a2bc335
BP
1289 bool "CPU microcode loading support"
1290 default y
80030e3d 1291 depends on CPU_SUP_AMD || CPU_SUP_INTEL
506f1d07
SR
1292 select FW_LOADER
1293 ---help---
1294 If you say Y here, you will be able to update the microcode on
5f9c01aa
BP
1295 Intel and AMD processors. The Intel support is for the IA32 family,
1296 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1297 AMD support is for families 0x10 and later. You will obviously need
1298 the actual microcode binary data itself which is not shipped with
1299 the Linux kernel.
1300
1301 The preferred method to load microcode from a detached initrd is described
1897a969 1302 in Documentation/x86/microcode.txt. For that you need to enable
5f9c01aa
BP
1303 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1304 initrd for microcode blobs.
1305
c508c46e
BG
1306 In addition, you can build the microcode into the kernel. For that you
1307 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1308 config option.
506f1d07 1309
8d86f390 1310config MICROCODE_INTEL
e43f6e67 1311 bool "Intel microcode loading support"
8f9ca475
IM
1312 depends on MICROCODE
1313 default MICROCODE
1314 select FW_LOADER
1315 ---help---
1316 This options enables microcode patch loading support for Intel
1317 processors.
1318
b8989db9
A
1319 For the current Intel microcode data package go to
1320 <https://downloadcenter.intel.com> and search for
1321 'Linux Processor Microcode Data File'.
8d86f390 1322
80cc9f10 1323config MICROCODE_AMD
e43f6e67 1324 bool "AMD microcode loading support"
8f9ca475
IM
1325 depends on MICROCODE
1326 select FW_LOADER
1327 ---help---
1328 If you select this option, microcode patch loading support for AMD
1329 processors will be enabled.
80cc9f10 1330
8f9ca475 1331config MICROCODE_OLD_INTERFACE
3c2362e6 1332 def_bool y
506f1d07 1333 depends on MICROCODE
506f1d07
SR
1334
1335config X86_MSR
1336 tristate "/dev/cpu/*/msr - Model-specific register support"
8f9ca475 1337 ---help---
506f1d07
SR
1338 This device gives privileged processes access to the x86
1339 Model-Specific Registers (MSRs). It is a character device with
1340 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1341 MSR accesses are directed to a specific CPU on multi-processor
1342 systems.
1343
1344config X86_CPUID
1345 tristate "/dev/cpu/*/cpuid - CPU information support"
8f9ca475 1346 ---help---
506f1d07
SR
1347 This device gives processes access to the x86 CPUID instruction to
1348 be executed on a specific processor. It is a character device
1349 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1350 /dev/cpu/31/cpuid.
1351
1352choice
1353 prompt "High Memory Support"
6fc108a0 1354 default HIGHMEM4G
506f1d07
SR
1355 depends on X86_32
1356
1357config NOHIGHMEM
1358 bool "off"
506f1d07
SR
1359 ---help---
1360 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1361 However, the address space of 32-bit x86 processors is only 4
1362 Gigabytes large. That means that, if you have a large amount of
1363 physical memory, not all of it can be "permanently mapped" by the
1364 kernel. The physical memory that's not permanently mapped is called
1365 "high memory".
1366
1367 If you are compiling a kernel which will never run on a machine with
1368 more than 1 Gigabyte total physical RAM, answer "off" here (default
1369 choice and suitable for most users). This will result in a "3GB/1GB"
1370 split: 3GB are mapped so that each process sees a 3GB virtual memory
1371 space and the remaining part of the 4GB virtual memory space is used
1372 by the kernel to permanently map as much physical memory as
1373 possible.
1374
1375 If the machine has between 1 and 4 Gigabytes physical RAM, then
1376 answer "4GB" here.
1377
1378 If more than 4 Gigabytes is used then answer "64GB" here. This
1379 selection turns Intel PAE (Physical Address Extension) mode on.
1380 PAE implements 3-level paging on IA32 processors. PAE is fully
1381 supported by Linux, PAE mode is implemented on all recent Intel
1382 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1383 then the kernel will not boot on CPUs that don't support PAE!
1384
1385 The actual amount of total physical memory will either be
1386 auto detected or can be forced by using a kernel command line option
1387 such as "mem=256M". (Try "man bootparam" or see the documentation of
1388 your boot loader (lilo or loadlin) about how to pass options to the
1389 kernel at boot time.)
1390
1391 If unsure, say "off".
1392
1393config HIGHMEM4G
1394 bool "4GB"
8f9ca475 1395 ---help---
506f1d07
SR
1396 Select this if you have a 32-bit processor and between 1 and 4
1397 gigabytes of physical RAM.
1398
1399config HIGHMEM64G
1400 bool "64GB"
69b8d3fc 1401 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
506f1d07 1402 select X86_PAE
8f9ca475 1403 ---help---
506f1d07
SR
1404 Select this if you have a 32-bit processor and more than 4
1405 gigabytes of physical RAM.
1406
1407endchoice
1408
1409choice
6a108a14 1410 prompt "Memory split" if EXPERT
506f1d07
SR
1411 default VMSPLIT_3G
1412 depends on X86_32
8f9ca475 1413 ---help---
506f1d07
SR
1414 Select the desired split between kernel and user memory.
1415
1416 If the address range available to the kernel is less than the
1417 physical memory installed, the remaining memory will be available
1418 as "high memory". Accessing high memory is a little more costly
1419 than low memory, as it needs to be mapped into the kernel first.
1420 Note that increasing the kernel address space limits the range
1421 available to user programs, making the address space there
1422 tighter. Selecting anything other than the default 3G/1G split
1423 will also likely make your kernel incompatible with binary-only
1424 kernel modules.
1425
1426 If you are not absolutely sure what you are doing, leave this
1427 option alone!
1428
1429 config VMSPLIT_3G
1430 bool "3G/1G user/kernel split"
1431 config VMSPLIT_3G_OPT
1432 depends on !X86_PAE
1433 bool "3G/1G user/kernel split (for full 1G low memory)"
1434 config VMSPLIT_2G
1435 bool "2G/2G user/kernel split"
1436 config VMSPLIT_2G_OPT
1437 depends on !X86_PAE
1438 bool "2G/2G user/kernel split (for full 2G low memory)"
1439 config VMSPLIT_1G
1440 bool "1G/3G user/kernel split"
1441endchoice
1442
1443config PAGE_OFFSET
1444 hex
1445 default 0xB0000000 if VMSPLIT_3G_OPT
1446 default 0x80000000 if VMSPLIT_2G
1447 default 0x78000000 if VMSPLIT_2G_OPT
1448 default 0x40000000 if VMSPLIT_1G
1449 default 0xC0000000
1450 depends on X86_32
1451
1452config HIGHMEM
3c2362e6 1453 def_bool y
506f1d07 1454 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
506f1d07
SR
1455
1456config X86_PAE
9ba16087 1457 bool "PAE (Physical Address Extension) Support"
506f1d07 1458 depends on X86_32 && !HIGHMEM4G
d4a451d5 1459 select PHYS_ADDR_T_64BIT
9d99c712 1460 select SWIOTLB
8f9ca475 1461 ---help---
506f1d07
SR
1462 PAE is required for NX support, and furthermore enables
1463 larger swapspace support for non-overcommit purposes. It
1464 has the cost of more pagetable lookup overhead, and also
1465 consumes more pagetable space per process.
1466
77ef56e4
KS
1467config X86_5LEVEL
1468 bool "Enable 5-level page tables support"
eedb92ab 1469 select DYNAMIC_MEMORY_LAYOUT
162434e7 1470 select SPARSEMEM_VMEMMAP
77ef56e4
KS
1471 depends on X86_64
1472 ---help---
1473 5-level paging enables access to larger address space:
1474 upto 128 PiB of virtual address space and 4 PiB of
1475 physical address space.
1476
1477 It will be supported by future Intel CPUs.
1478
6657fca0
KS
1479 A kernel with the option enabled can be booted on machines that
1480 support 4- or 5-level paging.
77ef56e4
KS
1481
1482 See Documentation/x86/x86_64/5level-paging.txt for more
1483 information.
1484
1485 Say N if unsure.
1486
10971ab2 1487config X86_DIRECT_GBPAGES
e5008abe 1488 def_bool y
4675ff05 1489 depends on X86_64 && !DEBUG_PAGEALLOC
8f9ca475 1490 ---help---
10971ab2
IM
1491 Certain kernel features effectively disable kernel
1492 linear 1 GB mappings (even if the CPU otherwise
1493 supports them), so don't confuse the user by printing
1494 that we have them enabled.
9e899816 1495
7744ccdb
TL
1496config ARCH_HAS_MEM_ENCRYPT
1497 def_bool y
1498
1499config AMD_MEM_ENCRYPT
1500 bool "AMD Secure Memory Encryption (SME) support"
1501 depends on X86_64 && CPU_SUP_AMD
94d49eb3 1502 select DYNAMIC_PHYSICAL_MASK
7744ccdb
TL
1503 ---help---
1504 Say yes to enable support for the encryption of system memory.
1505 This requires an AMD processor that supports Secure Memory
1506 Encryption (SME).
1507
1508config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1509 bool "Activate AMD Secure Memory Encryption (SME) by default"
1510 default y
1511 depends on AMD_MEM_ENCRYPT
1512 ---help---
1513 Say yes to have system memory encrypted by default if running on
1514 an AMD processor that supports Secure Memory Encryption (SME).
1515
1516 If set to Y, then the encryption of system memory can be
1517 deactivated with the mem_encrypt=off command line option.
1518
1519 If set to N, then the encryption of system memory can be
1520 activated with the mem_encrypt=on command line option.
1521
f88a68fa
TL
1522config ARCH_USE_MEMREMAP_PROT
1523 def_bool y
1524 depends on AMD_MEM_ENCRYPT
1525
506f1d07
SR
1526# Common NUMA Features
1527config NUMA
fd51b2d7 1528 bool "Numa Memory Allocation and Scheduler Support"
506f1d07 1529 depends on SMP
b5660ba7
PA
1530 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1531 default y if X86_BIGSMP
8f9ca475 1532 ---help---
506f1d07 1533 Enable NUMA (Non Uniform Memory Access) support.
fd51b2d7 1534
506f1d07
SR
1535 The kernel will try to allocate memory used by a CPU on the
1536 local memory controller of the CPU and add some more
1537 NUMA awareness to the kernel.
1538
c280ea5e 1539 For 64-bit this is recommended if the system is Intel Core i7
fd51b2d7
KM
1540 (or later), AMD Opteron, or EM64T NUMA.
1541
b5660ba7 1542 For 32-bit this is only needed if you boot a 32-bit
7cf6c945 1543 kernel on a 64-bit NUMA platform.
fd51b2d7
KM
1544
1545 Otherwise, you should say N.
506f1d07 1546
eec1d4fa 1547config AMD_NUMA
3c2362e6
HH
1548 def_bool y
1549 prompt "Old style AMD Opteron NUMA detection"
5da0ef9a 1550 depends on X86_64 && NUMA && PCI
8f9ca475 1551 ---help---
eec1d4fa
HR
1552 Enable AMD NUMA node topology detection. You should say Y here if
1553 you have a multi processor AMD system. This uses an old method to
1554 read the NUMA configuration directly from the builtin Northbridge
1555 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1556 which also takes priority if both are compiled in.
506f1d07
SR
1557
1558config X86_64_ACPI_NUMA
3c2362e6
HH
1559 def_bool y
1560 prompt "ACPI NUMA detection"
506f1d07
SR
1561 depends on X86_64 && NUMA && ACPI && PCI
1562 select ACPI_NUMA
8f9ca475 1563 ---help---
506f1d07
SR
1564 Enable ACPI SRAT based node topology detection.
1565
6ec6e0d9
SS
1566# Some NUMA nodes have memory ranges that span
1567# other nodes. Even though a pfn is valid and
1568# between a node's start and end pfns, it may not
1569# reside on that node. See memmap_init_zone()
1570# for details.
1571config NODES_SPAN_OTHER_NODES
1572 def_bool y
1573 depends on X86_64_ACPI_NUMA
1574
506f1d07
SR
1575config NUMA_EMU
1576 bool "NUMA emulation"
1b7e03ef 1577 depends on NUMA
8f9ca475 1578 ---help---
506f1d07
SR
1579 Enable NUMA emulation. A flat machine will be split
1580 into virtual nodes when booted with "numa=fake=N", where N is the
1581 number of nodes. This is only useful for debugging.
1582
1583config NODES_SHIFT
d25e26b6 1584 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
51591e31
DR
1585 range 1 10
1586 default "10" if MAXSMP
506f1d07 1587 default "6" if X86_64
506f1d07
SR
1588 default "3"
1589 depends on NEED_MULTIPLE_NODES
8f9ca475 1590 ---help---
1184dc2f 1591 Specify the maximum number of NUMA Nodes available on the target
692105b8 1592 system. Increases memory reserved to accommodate various tables.
506f1d07 1593
506f1d07 1594config ARCH_HAVE_MEMORY_PRESENT
3c2362e6 1595 def_bool y
506f1d07 1596 depends on X86_32 && DISCONTIGMEM
506f1d07 1597
506f1d07
SR
1598config ARCH_FLATMEM_ENABLE
1599 def_bool y
3b16651f 1600 depends on X86_32 && !NUMA
506f1d07
SR
1601
1602config ARCH_DISCONTIGMEM_ENABLE
1603 def_bool y
b263295d 1604 depends on NUMA && X86_32
506f1d07
SR
1605
1606config ARCH_DISCONTIGMEM_DEFAULT
1607 def_bool y
b263295d
CL
1608 depends on NUMA && X86_32
1609
506f1d07
SR
1610config ARCH_SPARSEMEM_ENABLE
1611 def_bool y
6ea30386 1612 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
506f1d07
SR
1613 select SPARSEMEM_STATIC if X86_32
1614 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1615
3b16651f
TH
1616config ARCH_SPARSEMEM_DEFAULT
1617 def_bool y
1618 depends on X86_64
1619
506f1d07
SR
1620config ARCH_SELECT_MEMORY_MODEL
1621 def_bool y
b263295d 1622 depends on ARCH_SPARSEMEM_ENABLE
506f1d07
SR
1623
1624config ARCH_MEMORY_PROBE
a0842b70 1625 bool "Enable sysfs memory/probe interface"
3120e25e 1626 depends on X86_64 && MEMORY_HOTPLUG
a0842b70
TK
1627 help
1628 This option enables a sysfs memory/probe interface for testing.
1629 See Documentation/memory-hotplug.txt for more information.
1630 If you are unsure how to answer this question, answer N.
506f1d07 1631
3b16651f
TH
1632config ARCH_PROC_KCORE_TEXT
1633 def_bool y
1634 depends on X86_64 && PROC_KCORE
1635
a29815a3
AK
1636config ILLEGAL_POINTER_VALUE
1637 hex
1638 default 0 if X86_32
1639 default 0xdead000000000000 if X86_64
1640
506f1d07
SR
1641source "mm/Kconfig"
1642
7a67832c
DW
1643config X86_PMEM_LEGACY_DEVICE
1644 bool
1645
ec776ef6 1646config X86_PMEM_LEGACY
7a67832c 1647 tristate "Support non-standard NVDIMMs and ADR protected memory"
9f53f9fa
DW
1648 depends on PHYS_ADDR_T_64BIT
1649 depends on BLK_DEV
7a67832c 1650 select X86_PMEM_LEGACY_DEVICE
9f53f9fa 1651 select LIBNVDIMM
ec776ef6
CH
1652 help
1653 Treat memory marked using the non-standard e820 type of 12 as used
1654 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1655 The kernel will offer these regions to the 'pmem' driver so
1656 they can be used for persistent storage.
1657
1658 Say Y if unsure.
1659
506f1d07
SR
1660config HIGHPTE
1661 bool "Allocate 3rd-level pagetables from highmem"
6fc108a0 1662 depends on HIGHMEM
8f9ca475 1663 ---help---
506f1d07
SR
1664 The VM uses one page table entry for each page of physical memory.
1665 For systems with a lot of RAM, this can be wasteful of precious
1666 low memory. Setting this option will put user-space page table
1667 entries in high memory.
1668
9f077871 1669config X86_CHECK_BIOS_CORRUPTION
8f9ca475
IM
1670 bool "Check for low memory corruption"
1671 ---help---
1672 Periodically check for memory corruption in low memory, which
1673 is suspected to be caused by BIOS. Even when enabled in the
1674 configuration, it is disabled at runtime. Enable it by
1675 setting "memory_corruption_check=1" on the kernel command
1676 line. By default it scans the low 64k of memory every 60
1677 seconds; see the memory_corruption_check_size and
1678 memory_corruption_check_period parameters in
8c27ceff 1679 Documentation/admin-guide/kernel-parameters.rst to adjust this.
8f9ca475
IM
1680
1681 When enabled with the default parameters, this option has
1682 almost no overhead, as it reserves a relatively small amount
1683 of memory and scans it infrequently. It both detects corruption
1684 and prevents it from affecting the running system.
1685
1686 It is, however, intended as a diagnostic tool; if repeatable
1687 BIOS-originated corruption always affects the same memory,
1688 you can use memmap= to prevent the kernel from using that
1689 memory.
9f077871 1690
c885df50 1691config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
8f9ca475 1692 bool "Set the default setting of memory_corruption_check"
c885df50
JF
1693 depends on X86_CHECK_BIOS_CORRUPTION
1694 default y
8f9ca475
IM
1695 ---help---
1696 Set whether the default state of memory_corruption_check is
1697 on or off.
c885df50 1698
9ea77bdb 1699config X86_RESERVE_LOW
d0cd7425
PA
1700 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1701 default 64
1702 range 4 640
8f9ca475 1703 ---help---
d0cd7425
PA
1704 Specify the amount of low memory to reserve for the BIOS.
1705
1706 The first page contains BIOS data structures that the kernel
1707 must not use, so that page must always be reserved.
1708
1709 By default we reserve the first 64K of physical RAM, as a
1710 number of BIOSes are known to corrupt that memory range
1711 during events such as suspend/resume or monitor cable
1712 insertion, so it must not be used by the kernel.
fc381519 1713
d0cd7425
PA
1714 You can set this to 4 if you are absolutely sure that you
1715 trust the BIOS to get all its memory reservations and usages
1716 right. If you know your BIOS have problems beyond the
1717 default 64K area, you can set this to 640 to avoid using the
1718 entire low memory range.
fc381519 1719
d0cd7425
PA
1720 If you have doubts about the BIOS (e.g. suspend/resume does
1721 not work or there's kernel crashes after certain hardware
1722 hotplug events) then you might want to enable
1723 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1724 typical corruption patterns.
fc381519 1725
d0cd7425 1726 Leave this to the default value of 64 if you are unsure.
fc381519 1727
506f1d07
SR
1728config MATH_EMULATION
1729 bool
a5b9e5a2 1730 depends on MODIFY_LDT_SYSCALL
506f1d07
SR
1731 prompt "Math emulation" if X86_32
1732 ---help---
1733 Linux can emulate a math coprocessor (used for floating point
1734 operations) if you don't have one. 486DX and Pentium processors have
1735 a math coprocessor built in, 486SX and 386 do not, unless you added
1736 a 487DX or 387, respectively. (The messages during boot time can
1737 give you some hints here ["man dmesg"].) Everyone needs either a
1738 coprocessor or this emulation.
1739
1740 If you don't have a math coprocessor, you need to say Y here; if you
1741 say Y here even though you have a coprocessor, the coprocessor will
1742 be used nevertheless. (This behavior can be changed with the kernel
1743 command line option "no387", which comes handy if your coprocessor
1744 is broken. Try "man bootparam" or see the documentation of your boot
1745 loader (lilo or loadlin) about how to pass options to the kernel at
1746 boot time.) This means that it is a good idea to say Y here if you
1747 intend to use this kernel on different machines.
1748
1749 More information about the internals of the Linux math coprocessor
1750 emulation can be found in <file:arch/x86/math-emu/README>.
1751
1752 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1753 kernel, it won't hurt.
1754
1755config MTRR
6fc108a0 1756 def_bool y
6a108a14 1757 prompt "MTRR (Memory Type Range Register) support" if EXPERT
506f1d07
SR
1758 ---help---
1759 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1760 the Memory Type Range Registers (MTRRs) may be used to control
1761 processor access to memory ranges. This is most useful if you have
1762 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1763 allows bus write transfers to be combined into a larger transfer
1764 before bursting over the PCI/AGP bus. This can increase performance
1765 of image write operations 2.5 times or more. Saying Y here creates a
1766 /proc/mtrr file which may be used to manipulate your processor's
1767 MTRRs. Typically the X server should use this.
1768
1769 This code has a reasonably generic interface so that similar
1770 control registers on other processors can be easily supported
1771 as well:
1772
1773 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1774 Registers (ARRs) which provide a similar functionality to MTRRs. For
1775 these, the ARRs are used to emulate the MTRRs.
1776 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1777 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1778 write-combining. All of these processors are supported by this code
1779 and it makes sense to say Y here if you have one of them.
1780
1781 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1782 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1783 can lead to all sorts of problems, so it's good to say Y here.
1784
1785 You can safely say Y even if your machine doesn't have MTRRs, you'll
1786 just add about 9 KB to your kernel.
1787
7225e751 1788 See <file:Documentation/x86/mtrr.txt> for more information.
506f1d07 1789
95ffa243 1790config MTRR_SANITIZER
2ffb3501 1791 def_bool y
95ffa243
YL
1792 prompt "MTRR cleanup support"
1793 depends on MTRR
8f9ca475 1794 ---help---
aba3728c
TG
1795 Convert MTRR layout from continuous to discrete, so X drivers can
1796 add writeback entries.
95ffa243 1797
aba3728c 1798 Can be disabled with disable_mtrr_cleanup on the kernel command line.
692105b8 1799 The largest mtrr entry size for a continuous block can be set with
aba3728c 1800 mtrr_chunk_size.
95ffa243 1801
2ffb3501 1802 If unsure, say Y.
95ffa243
YL
1803
1804config MTRR_SANITIZER_ENABLE_DEFAULT
f5098d62
YL
1805 int "MTRR cleanup enable value (0-1)"
1806 range 0 1
1807 default "0"
95ffa243 1808 depends on MTRR_SANITIZER
8f9ca475 1809 ---help---
f5098d62 1810 Enable mtrr cleanup default value
95ffa243 1811
12031a62
YL
1812config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1813 int "MTRR cleanup spare reg num (0-7)"
1814 range 0 7
1815 default "1"
1816 depends on MTRR_SANITIZER
8f9ca475 1817 ---help---
12031a62 1818 mtrr cleanup spare entries default, it can be changed via
aba3728c 1819 mtrr_spare_reg_nr=N on the kernel command line.
12031a62 1820
2e5d9c85 1821config X86_PAT
6fc108a0 1822 def_bool y
6a108a14 1823 prompt "x86 PAT support" if EXPERT
2a8a2719 1824 depends on MTRR
8f9ca475 1825 ---help---
2e5d9c85 1826 Use PAT attributes to setup page level cache control.
042b78e4 1827
2e5d9c85 1828 PATs are the modern equivalents of MTRRs and are much more
1829 flexible than MTRRs.
1830
1831 Say N here if you see bootup problems (boot crash, boot hang,
042b78e4 1832 spontaneous reboots) or a non-working video driver.
2e5d9c85 1833
1834 If unsure, say Y.
1835
46cf98cd
VP
1836config ARCH_USES_PG_UNCACHED
1837 def_bool y
1838 depends on X86_PAT
1839
628c6246
PA
1840config ARCH_RANDOM
1841 def_bool y
1842 prompt "x86 architectural random number generator" if EXPERT
1843 ---help---
1844 Enable the x86 architectural RDRAND instruction
1845 (Intel Bull Mountain technology) to generate random numbers.
1846 If supported, this is a high bandwidth, cryptographically
1847 secure hardware random number generator.
1848
51ae4a2d
PA
1849config X86_SMAP
1850 def_bool y
1851 prompt "Supervisor Mode Access Prevention" if EXPERT
1852 ---help---
1853 Supervisor Mode Access Prevention (SMAP) is a security
1854 feature in newer Intel processors. There is a small
1855 performance cost if this enabled and turned on; there is
1856 also a small increase in the kernel size if this is enabled.
1857
1858 If unsure, say Y.
1859
aa35f896 1860config X86_INTEL_UMIP
796ebc81 1861 def_bool y
aa35f896
RN
1862 depends on CPU_SUP_INTEL
1863 prompt "Intel User Mode Instruction Prevention" if EXPERT
1864 ---help---
1865 The User Mode Instruction Prevention (UMIP) is a security
1866 feature in newer Intel processors. If enabled, a general
796ebc81
RN
1867 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1868 or STR instructions are executed in user mode. These instructions
1869 unnecessarily expose information about the hardware state.
1870
1871 The vast majority of applications do not use these instructions.
1872 For the very few that do, software emulation is provided in
1873 specific cases in protected and virtual-8086 modes. Emulated
1874 results are dummy.
aa35f896 1875
72e9b5fe
DH
1876config X86_INTEL_MPX
1877 prompt "Intel MPX (Memory Protection Extensions)"
1878 def_bool n
df3735c5
RR
1879 # Note: only available in 64-bit mode due to VMA flags shortage
1880 depends on CPU_SUP_INTEL && X86_64
1881 select ARCH_USES_HIGH_VMA_FLAGS
72e9b5fe
DH
1882 ---help---
1883 MPX provides hardware features that can be used in
1884 conjunction with compiler-instrumented code to check
1885 memory references. It is designed to detect buffer
1886 overflow or underflow bugs.
1887
1888 This option enables running applications which are
1889 instrumented or otherwise use MPX. It does not use MPX
1890 itself inside the kernel or to protect the kernel
1891 against bad memory references.
1892
1893 Enabling this option will make the kernel larger:
1894 ~8k of kernel text and 36 bytes of data on a 64-bit
1895 defconfig. It adds a long to the 'mm_struct' which
1896 will increase the kernel memory overhead of each
1897 process and adds some branches to paths used during
1898 exec() and munmap().
1899
1900 For details, see Documentation/x86/intel_mpx.txt
1901
1902 If unsure, say N.
1903
35e97790 1904config X86_INTEL_MEMORY_PROTECTION_KEYS
284244a9 1905 prompt "Intel Memory Protection Keys"
35e97790 1906 def_bool y
284244a9 1907 # Note: only available in 64-bit mode
35e97790 1908 depends on CPU_SUP_INTEL && X86_64
52c8e601
IM
1909 select ARCH_USES_HIGH_VMA_FLAGS
1910 select ARCH_HAS_PKEYS
284244a9
DH
1911 ---help---
1912 Memory Protection Keys provides a mechanism for enforcing
1913 page-based protections, but without requiring modification of the
1914 page tables when an application changes protection domains.
1915
1916 For details, see Documentation/x86/protection-keys.txt
1917
1918 If unsure, say y.
35e97790 1919
506f1d07 1920config EFI
9ba16087 1921 bool "EFI runtime service support"
5b83683f 1922 depends on ACPI
f6ce5002 1923 select UCS2_STRING
022ee6c5 1924 select EFI_RUNTIME_WRAPPERS
506f1d07 1925 ---help---
8f9ca475
IM
1926 This enables the kernel to use EFI runtime services that are
1927 available (such as the EFI variable services).
506f1d07 1928
8f9ca475
IM
1929 This option is only useful on systems that have EFI firmware.
1930 In addition, you should use the latest ELILO loader available
1931 at <http://elilo.sourceforge.net> in order to take advantage
1932 of EFI runtime services. However, even with this option, the
1933 resultant kernel should continue to boot on existing non-EFI
1934 platforms.
506f1d07 1935
291f3632
MF
1936config EFI_STUB
1937 bool "EFI stub support"
b16d8c23 1938 depends on EFI && !X86_USE_3DNOW
7b2a583a 1939 select RELOCATABLE
291f3632
MF
1940 ---help---
1941 This kernel feature allows a bzImage to be loaded directly
1942 by EFI firmware without the use of a bootloader.
1943
4172fe2f 1944 See Documentation/efi-stub.txt for more information.
0c759662 1945
7d453eee
MF
1946config EFI_MIXED
1947 bool "EFI mixed-mode support"
1948 depends on EFI_STUB && X86_64
1949 ---help---
1950 Enabling this feature allows a 64-bit kernel to be booted
1951 on a 32-bit firmware, provided that your CPU supports 64-bit
1952 mode.
1953
1954 Note that it is not possible to boot a mixed-mode enabled
1955 kernel via the EFI boot stub - a bootloader that supports
1956 the EFI handover protocol must be used.
1957
1958 If unsure, say N.
1959
506f1d07 1960config SECCOMP
3c2362e6
HH
1961 def_bool y
1962 prompt "Enable seccomp to safely compute untrusted bytecode"
8f9ca475 1963 ---help---
506f1d07
SR
1964 This kernel feature is useful for number crunching applications
1965 that may need to compute untrusted bytecode during their
1966 execution. By using pipes or other transports made available to
1967 the process as file descriptors supporting the read/write
1968 syscalls, it's possible to isolate those applications in
1969 their own address space using seccomp. Once seccomp is
9c0bbee8 1970 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
506f1d07
SR
1971 and the task is only allowed to execute a few safe syscalls
1972 defined by each seccomp mode.
1973
1974 If unsure, say Y. Only embedded should say N here.
1975
506f1d07
SR
1976source kernel/Kconfig.hz
1977
1978config KEXEC
1979 bool "kexec system call"
2965faa5 1980 select KEXEC_CORE
8f9ca475 1981 ---help---
506f1d07
SR
1982 kexec is a system call that implements the ability to shutdown your
1983 current kernel, and to start another kernel. It is like a reboot
1984 but it is independent of the system firmware. And like a reboot
1985 you can start any kernel with it, not just Linux.
1986
1987 The name comes from the similarity to the exec system call.
1988
1989 It is an ongoing process to be certain the hardware in a machine
1990 is properly shutdown, so do not be surprised if this code does not
bf220695
GU
1991 initially work for you. As of this writing the exact hardware
1992 interface is strongly in flux, so no good recommendation can be
1993 made.
506f1d07 1994
74ca317c
VG
1995config KEXEC_FILE
1996 bool "kexec file based system call"
2965faa5 1997 select KEXEC_CORE
74ca317c 1998 select BUILD_BIN2C
74ca317c
VG
1999 depends on X86_64
2000 depends on CRYPTO=y
2001 depends on CRYPTO_SHA256=y
2002 ---help---
2003 This is new version of kexec system call. This system call is
2004 file based and takes file descriptors as system call argument
2005 for kernel and initramfs as opposed to list of segments as
2006 accepted by previous system call.
2007
b799a09f
AT
2008config ARCH_HAS_KEXEC_PURGATORY
2009 def_bool KEXEC_FILE
2010
8e7d8381
VG
2011config KEXEC_VERIFY_SIG
2012 bool "Verify kernel signature during kexec_file_load() syscall"
74ca317c 2013 depends on KEXEC_FILE
8e7d8381
VG
2014 ---help---
2015 This option makes kernel signature verification mandatory for
d8eb8940
BP
2016 the kexec_file_load() syscall.
2017
2018 In addition to that option, you need to enable signature
2019 verification for the corresponding kernel image type being
2020 loaded in order for this to work.
8e7d8381
VG
2021
2022config KEXEC_BZIMAGE_VERIFY_SIG
2023 bool "Enable bzImage signature verification support"
2024 depends on KEXEC_VERIFY_SIG
2025 depends on SIGNED_PE_FILE_VERIFICATION
2026 select SYSTEM_TRUSTED_KEYRING
2027 ---help---
2028 Enable bzImage signature verification support.
2029
506f1d07 2030config CRASH_DUMP
04b69447 2031 bool "kernel crash dumps"
506f1d07 2032 depends on X86_64 || (X86_32 && HIGHMEM)
8f9ca475 2033 ---help---
506f1d07
SR
2034 Generate crash dump after being started by kexec.
2035 This should be normally only set in special crash dump kernels
2036 which are loaded in the main kernel with kexec-tools into
2037 a specially reserved region and then later executed after
2038 a crash by kdump/kexec. The crash dump kernel must be compiled
2039 to a memory address not used by the main kernel or BIOS using
2040 PHYSICAL_START, or it must be built as a relocatable image
2041 (CONFIG_RELOCATABLE=y).
2042 For more details see Documentation/kdump/kdump.txt
2043
3ab83521 2044config KEXEC_JUMP
6ea30386 2045 bool "kexec jump"
fee7b0d8 2046 depends on KEXEC && HIBERNATION
8f9ca475 2047 ---help---
89081d17
HY
2048 Jump between original kernel and kexeced kernel and invoke
2049 code in physical address mode via KEXEC
3ab83521 2050
506f1d07 2051config PHYSICAL_START
6a108a14 2052 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
ceefccc9 2053 default "0x1000000"
8f9ca475 2054 ---help---
506f1d07
SR
2055 This gives the physical address where the kernel is loaded.
2056
2057 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2058 bzImage will decompress itself to above physical address and
2059 run from there. Otherwise, bzImage will run from the address where
2060 it has been loaded by the boot loader and will ignore above physical
2061 address.
2062
2063 In normal kdump cases one does not have to set/change this option
2064 as now bzImage can be compiled as a completely relocatable image
2065 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2066 address. This option is mainly useful for the folks who don't want
2067 to use a bzImage for capturing the crash dump and want to use a
2068 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2069 to be specifically compiled to run from a specific memory area
2070 (normally a reserved region) and this option comes handy.
2071
ceefccc9
PA
2072 So if you are using bzImage for capturing the crash dump,
2073 leave the value here unchanged to 0x1000000 and set
2074 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2075 for capturing the crash dump change this value to start of
2076 the reserved region. In other words, it can be set based on
2077 the "X" value as specified in the "crashkernel=YM@XM"
2078 command line boot parameter passed to the panic-ed
2079 kernel. Please take a look at Documentation/kdump/kdump.txt
2080 for more details about crash dumps.
506f1d07
SR
2081
2082 Usage of bzImage for capturing the crash dump is recommended as
2083 one does not have to build two kernels. Same kernel can be used
2084 as production kernel and capture kernel. Above option should have
2085 gone away after relocatable bzImage support is introduced. But it
2086 is present because there are users out there who continue to use
2087 vmlinux for dump capture. This option should go away down the
2088 line.
2089
2090 Don't change this unless you know what you are doing.
2091
2092config RELOCATABLE
26717808
PA
2093 bool "Build a relocatable kernel"
2094 default y
8f9ca475 2095 ---help---
506f1d07
SR
2096 This builds a kernel image that retains relocation information
2097 so it can be loaded someplace besides the default 1MB.
2098 The relocations tend to make the kernel binary about 10% larger,
2099 but are discarded at runtime.
2100
2101 One use is for the kexec on panic case where the recovery kernel
2102 must live at a different physical address than the primary
2103 kernel.
2104
2105 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2106 it has been loaded at and the compile time physical address
8ab3820f 2107 (CONFIG_PHYSICAL_START) is used as the minimum location.
506f1d07 2108
8ab3820f 2109config RANDOMIZE_BASE
e8581e3d 2110 bool "Randomize the address of the kernel image (KASLR)"
8ab3820f 2111 depends on RELOCATABLE
6807c846 2112 default y
8ab3820f 2113 ---help---
e8581e3d
BH
2114 In support of Kernel Address Space Layout Randomization (KASLR),
2115 this randomizes the physical address at which the kernel image
2116 is decompressed and the virtual address where the kernel
2117 image is mapped, as a security feature that deters exploit
2118 attempts relying on knowledge of the location of kernel
2119 code internals.
2120
ed9f007e
KC
2121 On 64-bit, the kernel physical and virtual addresses are
2122 randomized separately. The physical address will be anywhere
2123 between 16MB and the top of physical memory (up to 64TB). The
2124 virtual address will be randomized from 16MB up to 1GB (9 bits
2125 of entropy). Note that this also reduces the memory space
2126 available to kernel modules from 1.5GB to 1GB.
2127
2128 On 32-bit, the kernel physical and virtual addresses are
2129 randomized together. They will be randomized from 16MB up to
2130 512MB (8 bits of entropy).
e8581e3d
BH
2131
2132 Entropy is generated using the RDRAND instruction if it is
2133 supported. If RDTSC is supported, its value is mixed into
2134 the entropy pool as well. If neither RDRAND nor RDTSC are
ed9f007e
KC
2135 supported, then entropy is read from the i8254 timer. The
2136 usable entropy is limited by the kernel being built using
2137 2GB addressing, and that PHYSICAL_ALIGN must be at a
2138 minimum of 2MB. As a result, only 10 bits of entropy are
2139 theoretically possible, but the implementations are further
2140 limited due to memory layouts.
e8581e3d 2141
6807c846 2142 If unsure, say Y.
8ab3820f
KC
2143
2144# Relocation on x86 needs some additional build support
845adf72
PA
2145config X86_NEED_RELOCS
2146 def_bool y
8ab3820f 2147 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
845adf72 2148
506f1d07 2149config PHYSICAL_ALIGN
a0215061 2150 hex "Alignment value to which kernel should be aligned"
8ab3820f 2151 default "0x200000"
a0215061
KC
2152 range 0x2000 0x1000000 if X86_32
2153 range 0x200000 0x1000000 if X86_64
8f9ca475 2154 ---help---
506f1d07
SR
2155 This value puts the alignment restrictions on physical address
2156 where kernel is loaded and run from. Kernel is compiled for an
2157 address which meets above alignment restriction.
2158
2159 If bootloader loads the kernel at a non-aligned address and
2160 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2161 address aligned to above value and run from there.
2162
2163 If bootloader loads the kernel at a non-aligned address and
2164 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2165 load address and decompress itself to the address it has been
2166 compiled for and run from there. The address for which kernel is
2167 compiled already meets above alignment restrictions. Hence the
2168 end result is that kernel runs from a physical address meeting
2169 above alignment restrictions.
2170
a0215061
KC
2171 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2172 this value must be a multiple of 0x200000.
2173
506f1d07
SR
2174 Don't change this unless you know what you are doing.
2175
eedb92ab
KS
2176config DYNAMIC_MEMORY_LAYOUT
2177 bool
2178 ---help---
2179 This option makes base addresses of vmalloc and vmemmap as well as
2180 __PAGE_OFFSET movable during boot.
2181
0483e1fa
TG
2182config RANDOMIZE_MEMORY
2183 bool "Randomize the kernel memory sections"
2184 depends on X86_64
2185 depends on RANDOMIZE_BASE
eedb92ab 2186 select DYNAMIC_MEMORY_LAYOUT
0483e1fa
TG
2187 default RANDOMIZE_BASE
2188 ---help---
2189 Randomizes the base virtual address of kernel memory sections
2190 (physical memory mapping, vmalloc & vmemmap). This security feature
2191 makes exploits relying on predictable memory locations less reliable.
2192
2193 The order of allocations remains unchanged. Entropy is generated in
2194 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2195 configuration have in average 30,000 different possible virtual
2196 addresses for each memory section.
2197
6807c846 2198 If unsure, say Y.
0483e1fa 2199
90397a41
TG
2200config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2201 hex "Physical memory mapping padding" if EXPERT
2202 depends on RANDOMIZE_MEMORY
2203 default "0xa" if MEMORY_HOTPLUG
2204 default "0x0"
2205 range 0x1 0x40 if MEMORY_HOTPLUG
2206 range 0x0 0x40
2207 ---help---
2208 Define the padding in terabytes added to the existing physical
2209 memory size during kernel memory randomization. It is useful
2210 for memory hotplug support but reduces the entropy available for
2211 address randomization.
2212
2213 If unsure, leave at the default value.
2214
506f1d07 2215config HOTPLUG_CPU
7c13e6a3 2216 bool "Support for hot-pluggable CPUs"
40b31360 2217 depends on SMP
506f1d07 2218 ---help---
7c13e6a3
DS
2219 Say Y here to allow turning CPUs off and on. CPUs can be
2220 controlled through /sys/devices/system/cpu.
2221 ( Note: power management support will enable this option
2222 automatically on SMP systems. )
2223 Say N if you want to disable CPU hotplug.
506f1d07 2224
80aa1dff
FY
2225config BOOTPARAM_HOTPLUG_CPU0
2226 bool "Set default setting of cpu0_hotpluggable"
2227 default n
2c922cd0 2228 depends on HOTPLUG_CPU
80aa1dff
FY
2229 ---help---
2230 Set whether default state of cpu0_hotpluggable is on or off.
2231
2232 Say Y here to enable CPU0 hotplug by default. If this switch
2233 is turned on, there is no need to give cpu0_hotplug kernel
2234 parameter and the CPU0 hotplug feature is enabled by default.
2235
2236 Please note: there are two known CPU0 dependencies if you want
2237 to enable the CPU0 hotplug feature either by this switch or by
2238 cpu0_hotplug kernel parameter.
2239
2240 First, resume from hibernate or suspend always starts from CPU0.
2241 So hibernate and suspend are prevented if CPU0 is offline.
2242
2243 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2244 offline if any interrupt can not migrate out of CPU0. There may
2245 be other CPU0 dependencies.
2246
2247 Please make sure the dependencies are under your control before
2248 you enable this feature.
2249
2250 Say N if you don't want to enable CPU0 hotplug feature by default.
2251 You still can enable the CPU0 hotplug feature at boot by kernel
2252 parameter cpu0_hotplug.
2253
a71c8bc5
FY
2254config DEBUG_HOTPLUG_CPU0
2255 def_bool n
2256 prompt "Debug CPU0 hotplug"
2c922cd0 2257 depends on HOTPLUG_CPU
a71c8bc5
FY
2258 ---help---
2259 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2260 soon as possible and boots up userspace with CPU0 offlined. User
2261 can online CPU0 back after boot time.
2262
2263 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2264 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2265 compilation or giving cpu0_hotplug kernel parameter at boot.
2266
2267 If unsure, say N.
2268
506f1d07 2269config COMPAT_VDSO
b0b49f26
AL
2270 def_bool n
2271 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
953fee1d 2272 depends on COMPAT_32
8f9ca475 2273 ---help---
b0b49f26
AL
2274 Certain buggy versions of glibc will crash if they are
2275 presented with a 32-bit vDSO that is not mapped at the address
2276 indicated in its segment table.
e84446de 2277
b0b49f26
AL
2278 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2279 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2280 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2281 the only released version with the bug, but OpenSUSE 9
2282 contains a buggy "glibc 2.3.2".
506f1d07 2283
b0b49f26
AL
2284 The symptom of the bug is that everything crashes on startup, saying:
2285 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2286
2287 Saying Y here changes the default value of the vdso32 boot
2288 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2289 This works around the glibc bug but hurts performance.
2290
2291 If unsure, say N: if you are compiling your own kernel, you
2292 are unlikely to be using a buggy version of glibc.
506f1d07 2293
3dc33bd3
KC
2294choice
2295 prompt "vsyscall table for legacy applications"
2296 depends on X86_64
2297 default LEGACY_VSYSCALL_EMULATE
2298 help
2299 Legacy user code that does not know how to find the vDSO expects
2300 to be able to issue three syscalls by calling fixed addresses in
2301 kernel space. Since this location is not randomized with ASLR,
2302 it can be used to assist security vulnerability exploitation.
2303
2304 This setting can be changed at boot time via the kernel command
076ca272 2305 line parameter vsyscall=[emulate|none].
3dc33bd3
KC
2306
2307 On a system with recent enough glibc (2.14 or newer) and no
2308 static binaries, you can say None without a performance penalty
2309 to improve security.
2310
2311 If unsure, select "Emulate".
2312
3dc33bd3
KC
2313 config LEGACY_VSYSCALL_EMULATE
2314 bool "Emulate"
2315 help
2316 The kernel traps and emulates calls into the fixed
2317 vsyscall address mapping. This makes the mapping
2318 non-executable, but it still contains known contents,
2319 which could be used in certain rare security vulnerability
2320 exploits. This configuration is recommended when userspace
2321 still uses the vsyscall area.
2322
2323 config LEGACY_VSYSCALL_NONE
2324 bool "None"
2325 help
2326 There will be no vsyscall mapping at all. This will
2327 eliminate any risk of ASLR bypass due to the vsyscall
2328 fixed address mapping. Attempts to use the vsyscalls
2329 will be reported to dmesg, so that either old or
2330 malicious userspace programs can be identified.
2331
2332endchoice
2333
516cbf37
TB
2334config CMDLINE_BOOL
2335 bool "Built-in kernel command line"
8f9ca475 2336 ---help---
516cbf37
TB
2337 Allow for specifying boot arguments to the kernel at
2338 build time. On some systems (e.g. embedded ones), it is
2339 necessary or convenient to provide some or all of the
2340 kernel boot arguments with the kernel itself (that is,
2341 to not rely on the boot loader to provide them.)
2342
2343 To compile command line arguments into the kernel,
2344 set this option to 'Y', then fill in the
69711ca1 2345 boot arguments in CONFIG_CMDLINE.
516cbf37
TB
2346
2347 Systems with fully functional boot loaders (i.e. non-embedded)
2348 should leave this option set to 'N'.
2349
2350config CMDLINE
2351 string "Built-in kernel command string"
2352 depends on CMDLINE_BOOL
2353 default ""
8f9ca475 2354 ---help---
516cbf37
TB
2355 Enter arguments here that should be compiled into the kernel
2356 image and used at boot time. If the boot loader provides a
2357 command line at boot time, it is appended to this string to
2358 form the full kernel command line, when the system boots.
2359
2360 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2361 change this behavior.
2362
2363 In most cases, the command line (whether built-in or provided
2364 by the boot loader) should specify the device for the root
2365 file system.
2366
2367config CMDLINE_OVERRIDE
2368 bool "Built-in command line overrides boot loader arguments"
516cbf37 2369 depends on CMDLINE_BOOL
8f9ca475 2370 ---help---
516cbf37
TB
2371 Set this option to 'Y' to have the kernel ignore the boot loader
2372 command line, and use ONLY the built-in command line.
2373
2374 This is used to work around broken boot loaders. This should
2375 be set to 'N' under normal conditions.
2376
a5b9e5a2
AL
2377config MODIFY_LDT_SYSCALL
2378 bool "Enable the LDT (local descriptor table)" if EXPERT
2379 default y
2380 ---help---
2381 Linux can allow user programs to install a per-process x86
2382 Local Descriptor Table (LDT) using the modify_ldt(2) system
2383 call. This is required to run 16-bit or segmented code such as
2384 DOSEMU or some Wine programs. It is also used by some very old
2385 threading libraries.
2386
2387 Enabling this feature adds a small amount of overhead to
2388 context switches and increases the low-level kernel attack
2389 surface. Disabling it removes the modify_ldt(2) system call.
2390
2391 Saying 'N' here may make sense for embedded or server kernels.
2392
b700e7f0
SJ
2393source "kernel/livepatch/Kconfig"
2394
506f1d07
SR
2395endmenu
2396
3072e413
MH
2397config ARCH_HAS_ADD_PAGES
2398 def_bool y
2399 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2400
506f1d07
SR
2401config ARCH_ENABLE_MEMORY_HOTPLUG
2402 def_bool y
2403 depends on X86_64 || (X86_32 && HIGHMEM)
2404
35551053
GH
2405config ARCH_ENABLE_MEMORY_HOTREMOVE
2406 def_bool y
2407 depends on MEMORY_HOTPLUG
2408
e534c7c5 2409config USE_PERCPU_NUMA_NODE_ID
645a7919 2410 def_bool y
e534c7c5
LS
2411 depends on NUMA
2412
9491846f
KS
2413config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2414 def_bool y
2415 depends on X86_64 || X86_PAE
2416
c177c81e
NH
2417config ARCH_ENABLE_HUGEPAGE_MIGRATION
2418 def_bool y
2419 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2420
9c670ea3
NH
2421config ARCH_ENABLE_THP_MIGRATION
2422 def_bool y
2423 depends on X86_64 && TRANSPARENT_HUGEPAGE
2424
da85f865 2425menu "Power management and ACPI options"
e279b6c1
SR
2426
2427config ARCH_HIBERNATION_HEADER
3c2362e6 2428 def_bool y
e279b6c1 2429 depends on X86_64 && HIBERNATION
e279b6c1
SR
2430
2431source "kernel/power/Kconfig"
2432
2433source "drivers/acpi/Kconfig"
2434
efafc8b2
FT
2435source "drivers/sfi/Kconfig"
2436
a6b68076 2437config X86_APM_BOOT
6fc108a0 2438 def_bool y
282e5aab 2439 depends on APM
a6b68076 2440
e279b6c1
SR
2441menuconfig APM
2442 tristate "APM (Advanced Power Management) BIOS support"
efefa6f6 2443 depends on X86_32 && PM_SLEEP
e279b6c1
SR
2444 ---help---
2445 APM is a BIOS specification for saving power using several different
2446 techniques. This is mostly useful for battery powered laptops with
2447 APM compliant BIOSes. If you say Y here, the system time will be
2448 reset after a RESUME operation, the /proc/apm device will provide
2449 battery status information, and user-space programs will receive
2450 notification of APM "events" (e.g. battery status change).
2451
2452 If you select "Y" here, you can disable actual use of the APM
2453 BIOS by passing the "apm=off" option to the kernel at boot time.
2454
2455 Note that the APM support is almost completely disabled for
2456 machines with more than one CPU.
2457
2458 In order to use APM, you will need supporting software. For location
2dc98fd3
MW
2459 and more information, read <file:Documentation/power/apm-acpi.txt>
2460 and the Battery Powered Linux mini-HOWTO, available from
e279b6c1
SR
2461 <http://www.tldp.org/docs.html#howto>.
2462
2463 This driver does not spin down disk drives (see the hdparm(8)
2464 manpage ("man 8 hdparm") for that), and it doesn't turn off
2465 VESA-compliant "green" monitors.
2466
2467 This driver does not support the TI 4000M TravelMate and the ACER
2468 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2469 desktop machines also don't have compliant BIOSes, and this driver
2470 may cause those machines to panic during the boot phase.
2471
2472 Generally, if you don't have a battery in your machine, there isn't
2473 much point in using this driver and you should say N. If you get
2474 random kernel OOPSes or reboots that don't seem to be related to
2475 anything, try disabling/enabling this option (or disabling/enabling
2476 APM in your BIOS).
2477
2478 Some other things you should try when experiencing seemingly random,
2479 "weird" problems:
2480
2481 1) make sure that you have enough swap space and that it is
2482 enabled.
2483 2) pass the "no-hlt" option to the kernel
2484 3) switch on floating point emulation in the kernel and pass
2485 the "no387" option to the kernel
2486 4) pass the "floppy=nodma" option to the kernel
2487 5) pass the "mem=4M" option to the kernel (thereby disabling
2488 all but the first 4 MB of RAM)
2489 6) make sure that the CPU is not over clocked.
2490 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2491 8) disable the cache from your BIOS settings
2492 9) install a fan for the video card or exchange video RAM
2493 10) install a better fan for the CPU
2494 11) exchange RAM chips
2495 12) exchange the motherboard.
2496
2497 To compile this driver as a module, choose M here: the
2498 module will be called apm.
2499
2500if APM
2501
2502config APM_IGNORE_USER_SUSPEND
2503 bool "Ignore USER SUSPEND"
8f9ca475 2504 ---help---
e279b6c1
SR
2505 This option will ignore USER SUSPEND requests. On machines with a
2506 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2507 series notebooks, it is necessary to say Y because of a BIOS bug.
2508
2509config APM_DO_ENABLE
2510 bool "Enable PM at boot time"
2511 ---help---
2512 Enable APM features at boot time. From page 36 of the APM BIOS
2513 specification: "When disabled, the APM BIOS does not automatically
2514 power manage devices, enter the Standby State, enter the Suspend
2515 State, or take power saving steps in response to CPU Idle calls."
2516 This driver will make CPU Idle calls when Linux is idle (unless this
2517 feature is turned off -- see "Do CPU IDLE calls", below). This
2518 should always save battery power, but more complicated APM features
2519 will be dependent on your BIOS implementation. You may need to turn
2520 this option off if your computer hangs at boot time when using APM
2521 support, or if it beeps continuously instead of suspending. Turn
2522 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2523 T400CDT. This is off by default since most machines do fine without
2524 this feature.
2525
2526config APM_CPU_IDLE
dd8af076 2527 depends on CPU_IDLE
e279b6c1 2528 bool "Make CPU Idle calls when idle"
8f9ca475 2529 ---help---
e279b6c1
SR
2530 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2531 On some machines, this can activate improved power savings, such as
2532 a slowed CPU clock rate, when the machine is idle. These idle calls
2533 are made after the idle loop has run for some length of time (e.g.,
2534 333 mS). On some machines, this will cause a hang at boot time or
2535 whenever the CPU becomes idle. (On machines with more than one CPU,
2536 this option does nothing.)
2537
2538config APM_DISPLAY_BLANK
2539 bool "Enable console blanking using APM"
8f9ca475 2540 ---help---
e279b6c1
SR
2541 Enable console blanking using the APM. Some laptops can use this to
2542 turn off the LCD backlight when the screen blanker of the Linux
2543 virtual console blanks the screen. Note that this is only used by
2544 the virtual console screen blanker, and won't turn off the backlight
2545 when using the X Window system. This also doesn't have anything to
2546 do with your VESA-compliant power-saving monitor. Further, this
2547 option doesn't work for all laptops -- it might not turn off your
2548 backlight at all, or it might print a lot of errors to the console,
2549 especially if you are using gpm.
2550
2551config APM_ALLOW_INTS
2552 bool "Allow interrupts during APM BIOS calls"
8f9ca475 2553 ---help---
e279b6c1
SR
2554 Normally we disable external interrupts while we are making calls to
2555 the APM BIOS as a measure to lessen the effects of a badly behaving
2556 BIOS implementation. The BIOS should reenable interrupts if it
2557 needs to. Unfortunately, some BIOSes do not -- especially those in
2558 many of the newer IBM Thinkpads. If you experience hangs when you
2559 suspend, try setting this to Y. Otherwise, say N.
2560
e279b6c1
SR
2561endif # APM
2562
bb0a56ec 2563source "drivers/cpufreq/Kconfig"
e279b6c1
SR
2564
2565source "drivers/cpuidle/Kconfig"
2566
27471fdb
AH
2567source "drivers/idle/Kconfig"
2568
e279b6c1
SR
2569endmenu
2570
2571
2572menu "Bus options (PCI etc.)"
2573
2574config PCI
1ac97018 2575 bool "PCI support"
1c858087 2576 default y
8f9ca475 2577 ---help---
e279b6c1
SR
2578 Find out whether you have a PCI motherboard. PCI is the name of a
2579 bus system, i.e. the way the CPU talks to the other stuff inside
2580 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2581 VESA. If you have PCI, say Y, otherwise N.
2582
e279b6c1
SR
2583choice
2584 prompt "PCI access mode"
efefa6f6 2585 depends on X86_32 && PCI
e279b6c1
SR
2586 default PCI_GOANY
2587 ---help---
2588 On PCI systems, the BIOS can be used to detect the PCI devices and
2589 determine their configuration. However, some old PCI motherboards
2590 have BIOS bugs and may crash if this is done. Also, some embedded
2591 PCI-based systems don't have any BIOS at all. Linux can also try to
2592 detect the PCI hardware directly without using the BIOS.
2593
2594 With this option, you can specify how Linux should detect the
2595 PCI devices. If you choose "BIOS", the BIOS will be used,
2596 if you choose "Direct", the BIOS won't be used, and if you
2597 choose "MMConfig", then PCI Express MMCONFIG will be used.
2598 If you choose "Any", the kernel will try MMCONFIG, then the
2599 direct access method and falls back to the BIOS if that doesn't
2600 work. If unsure, go with the default, which is "Any".
2601
2602config PCI_GOBIOS
2603 bool "BIOS"
2604
2605config PCI_GOMMCONFIG
2606 bool "MMConfig"
2607
2608config PCI_GODIRECT
2609 bool "Direct"
2610
3ef0e1f8 2611config PCI_GOOLPC
76fb6570 2612 bool "OLPC XO-1"
3ef0e1f8
AS
2613 depends on OLPC
2614
2bdd1b03
AS
2615config PCI_GOANY
2616 bool "Any"
2617
e279b6c1
SR
2618endchoice
2619
2620config PCI_BIOS
3c2362e6 2621 def_bool y
efefa6f6 2622 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
e279b6c1
SR
2623
2624# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2625config PCI_DIRECT
3c2362e6 2626 def_bool y
0aba496f 2627 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
e279b6c1
SR
2628
2629config PCI_MMCONFIG
b45c9f36
JK
2630 bool "Support mmconfig PCI config space access" if X86_64
2631 default y
8364e1f8 2632 depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
b45c9f36 2633 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
e279b6c1 2634
3ef0e1f8 2635config PCI_OLPC
2bdd1b03
AS
2636 def_bool y
2637 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
3ef0e1f8 2638
b5401a96
AN
2639config PCI_XEN
2640 def_bool y
2641 depends on PCI && XEN
2642 select SWIOTLB_XEN
2643
e279b6c1 2644config PCI_DOMAINS
3c2362e6 2645 def_bool y
e279b6c1 2646 depends on PCI
e279b6c1 2647
8364e1f8
JK
2648config MMCONF_FAM10H
2649 def_bool y
2650 depends on X86_64 && PCI_MMCONFIG && ACPI
e279b6c1 2651
3f6ea84a 2652config PCI_CNB20LE_QUIRK
6a108a14 2653 bool "Read CNB20LE Host Bridge Windows" if EXPERT
6ea30386 2654 depends on PCI
3f6ea84a
IS
2655 help
2656 Read the PCI windows out of the CNB20LE host bridge. This allows
2657 PCI hotplug to work on systems with the CNB20LE chipset which do
2658 not have ACPI.
2659
64a5fed6
BH
2660 There's no public spec for this chipset, and this functionality
2661 is known to be incomplete.
2662
2663 You should say N unless you know you need this.
2664
e279b6c1
SR
2665source "drivers/pci/Kconfig"
2666
3a495511 2667config ISA_BUS
17a2a129 2668 bool "ISA bus support on modern systems" if EXPERT
3a495511 2669 help
17a2a129
WBG
2670 Expose ISA bus device drivers and options available for selection and
2671 configuration. Enable this option if your target machine has an ISA
2672 bus. ISA is an older system, displaced by PCI and newer bus
2673 architectures -- if your target machine is modern, it probably does
2674 not have an ISA bus.
3a495511
WBG
2675
2676 If unsure, say N.
2677
1c00f016 2678# x86_64 have no ISA slots, but can have ISA-style DMA.
e279b6c1 2679config ISA_DMA_API
1c00f016
DR
2680 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2681 default y
2682 help
2683 Enables ISA-style DMA support for devices requiring such controllers.
2684 If unsure, say Y.
e279b6c1 2685
51e68d05
LT
2686if X86_32
2687
e279b6c1
SR
2688config ISA
2689 bool "ISA support"
8f9ca475 2690 ---help---
e279b6c1
SR
2691 Find out whether you have ISA slots on your motherboard. ISA is the
2692 name of a bus system, i.e. the way the CPU talks to the other stuff
2693 inside your box. Other bus systems are PCI, EISA, MicroChannel
2694 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2695 newer boards don't support it. If you have ISA, say Y, otherwise N.
2696
2697config EISA
2698 bool "EISA support"
2699 depends on ISA
2700 ---help---
2701 The Extended Industry Standard Architecture (EISA) bus was
2702 developed as an open alternative to the IBM MicroChannel bus.
2703
2704 The EISA bus provided some of the features of the IBM MicroChannel
2705 bus while maintaining backward compatibility with cards made for
2706 the older ISA bus. The EISA bus saw limited use between 1988 and
2707 1995 when it was made obsolete by the PCI bus.
2708
2709 Say Y here if you are building a kernel for an EISA-based machine.
2710
2711 Otherwise, say N.
2712
2713source "drivers/eisa/Kconfig"
2714
e279b6c1
SR
2715config SCx200
2716 tristate "NatSemi SCx200 support"
8f9ca475 2717 ---help---
e279b6c1
SR
2718 This provides basic support for National Semiconductor's
2719 (now AMD's) Geode processors. The driver probes for the
2720 PCI-IDs of several on-chip devices, so its a good dependency
2721 for other scx200_* drivers.
2722
2723 If compiled as a module, the driver is named scx200.
2724
2725config SCx200HR_TIMER
2726 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
592913ec 2727 depends on SCx200
e279b6c1 2728 default y
8f9ca475 2729 ---help---
e279b6c1
SR
2730 This driver provides a clocksource built upon the on-chip
2731 27MHz high-resolution timer. Its also a workaround for
2732 NSC Geode SC-1100's buggy TSC, which loses time when the
2733 processor goes idle (as is done by the scheduler). The
2734 other workaround is idle=poll boot option.
2735
3ef0e1f8
AS
2736config OLPC
2737 bool "One Laptop Per Child support"
54008979 2738 depends on !X86_PAE
3c554946 2739 select GPIOLIB
dc3119e7 2740 select OF
45bb1674 2741 select OF_PROMTREE
b4e51854 2742 select IRQ_DOMAIN
8f9ca475 2743 ---help---
3ef0e1f8
AS
2744 Add support for detecting the unique features of the OLPC
2745 XO hardware.
2746
a3128588
DD
2747config OLPC_XO1_PM
2748 bool "OLPC XO-1 Power Management"
97c4cb71 2749 depends on OLPC && MFD_CS5535 && PM_SLEEP
a3128588 2750 select MFD_CORE
bf1ebf00 2751 ---help---
97c4cb71 2752 Add support for poweroff and suspend of the OLPC XO-1 laptop.
bf1ebf00 2753
cfee9597
DD
2754config OLPC_XO1_RTC
2755 bool "OLPC XO-1 Real Time Clock"
2756 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2757 ---help---
2758 Add support for the XO-1 real time clock, which can be used as a
2759 programmable wakeup source.
2760
7feda8e9
DD
2761config OLPC_XO1_SCI
2762 bool "OLPC XO-1 SCI extras"
92e830f2 2763 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
ed8e47fe 2764 depends on INPUT=y
d8d01a63 2765 select POWER_SUPPLY
7feda8e9
DD
2766 ---help---
2767 Add support for SCI-based features of the OLPC XO-1 laptop:
7bc74b3d 2768 - EC-driven system wakeups
7feda8e9 2769 - Power button
7bc74b3d 2770 - Ebook switch
2cf2baea 2771 - Lid switch
e1040ac6
DD
2772 - AC adapter status updates
2773 - Battery status updates
7feda8e9 2774
a0f30f59
DD
2775config OLPC_XO15_SCI
2776 bool "OLPC XO-1.5 SCI extras"
d8d01a63
DD
2777 depends on OLPC && ACPI
2778 select POWER_SUPPLY
a0f30f59
DD
2779 ---help---
2780 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2781 - EC-driven system wakeups
2782 - AC adapter status updates
2783 - Battery status updates
bf1ebf00 2784
d4f3e350
EW
2785config ALIX
2786 bool "PCEngines ALIX System Support (LED setup)"
2787 select GPIOLIB
2788 ---help---
2789 This option enables system support for the PCEngines ALIX.
2790 At present this just sets up LEDs for GPIO control on
2791 ALIX2/3/6 boards. However, other system specific setup should
2792 get added here.
2793
2794 Note: You must still enable the drivers for GPIO and LED support
2795 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2796
2797 Note: You have to set alix.force=1 for boards with Award BIOS.
2798
da4e3302
PP
2799config NET5501
2800 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2801 select GPIOLIB
2802 ---help---
2803 This option enables system support for the Soekris Engineering net5501.
2804
3197059a
PP
2805config GEOS
2806 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2807 select GPIOLIB
2808 depends on DMI
2809 ---help---
2810 This option enables system support for the Traverse Technologies GEOS.
2811
7d029125
VD
2812config TS5500
2813 bool "Technologic Systems TS-5500 platform support"
2814 depends on MELAN
2815 select CHECK_SIGNATURE
2816 select NEW_LEDS
2817 select LEDS_CLASS
2818 ---help---
2819 This option enables system support for the Technologic Systems TS-5500.
2820
bc0120fd
SR
2821endif # X86_32
2822
23ac4ae8 2823config AMD_NB
e279b6c1 2824 def_bool y
0e152cd7 2825 depends on CPU_SUP_AMD && PCI
e279b6c1
SR
2826
2827source "drivers/pcmcia/Kconfig"
2828
388b78ad 2829config RAPIDIO
fdf90abc 2830 tristate "RapidIO support"
388b78ad
AB
2831 depends on PCI
2832 default n
2833 help
fdf90abc 2834 If enabled this option will include drivers and the core
388b78ad
AB
2835 infrastructure code to support RapidIO interconnect devices.
2836
2837source "drivers/rapidio/Kconfig"
2838
e3263ab3
DH
2839config X86_SYSFB
2840 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2841 help
2842 Firmwares often provide initial graphics framebuffers so the BIOS,
2843 bootloader or kernel can show basic video-output during boot for
2844 user-guidance and debugging. Historically, x86 used the VESA BIOS
2845 Extensions and EFI-framebuffers for this, which are mostly limited
2846 to x86.
2847 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2848 framebuffers so the new generic system-framebuffer drivers can be
2849 used on x86. If the framebuffer is not compatible with the generic
2850 modes, it is adverticed as fallback platform framebuffer so legacy
2851 drivers like efifb, vesafb and uvesafb can pick it up.
2852 If this option is not selected, all system framebuffers are always
2853 marked as fallback platform framebuffers as usual.
2854
2855 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2856 not be able to pick up generic system framebuffers if this option
2857 is selected. You are highly encouraged to enable simplefb as
2858 replacement if you select this option. simplefb can correctly deal
2859 with generic system framebuffers. But you should still keep vesafb
2860 and others enabled as fallback if a system framebuffer is
2861 incompatible with simplefb.
2862
2863 If unsure, say Y.
2864
e279b6c1
SR
2865endmenu
2866
2867
2868menu "Executable file formats / Emulations"
2869
2870source "fs/Kconfig.binfmt"
2871
2872config IA32_EMULATION
2873 bool "IA32 Emulation"
2874 depends on X86_64
39f88911 2875 select ARCH_WANT_OLD_COMPAT_IPC
d1603990 2876 select BINFMT_ELF
a97f52e6 2877 select COMPAT_BINFMT_ELF
39f88911 2878 select COMPAT_OLD_SIGACTION
8f9ca475 2879 ---help---
5fd92e65
L
2880 Include code to run legacy 32-bit programs under a
2881 64-bit kernel. You should likely turn this on, unless you're
2882 100% sure that you don't have any 32-bit programs left.
e279b6c1
SR
2883
2884config IA32_AOUT
8f9ca475
IM
2885 tristate "IA32 a.out support"
2886 depends on IA32_EMULATION
2887 ---help---
2888 Support old a.out binaries in the 32bit emulation.
e279b6c1 2889
0bf62763 2890config X86_X32
6ea30386 2891 bool "x32 ABI for 64-bit mode"
9b54050b 2892 depends on X86_64
5fd92e65
L
2893 ---help---
2894 Include code to run binaries for the x32 native 32-bit ABI
2895 for 64-bit processors. An x32 process gets access to the
2896 full 64-bit register file and wide data path while leaving
2897 pointers at 32 bits for smaller memory footprint.
2898
2899 You will need a recent binutils (2.22 or later) with
2900 elf32_x86_64 support enabled to compile a kernel with this
2901 option set.
2902
953fee1d
IM
2903config COMPAT_32
2904 def_bool y
2905 depends on IA32_EMULATION || X86_32
2906 select HAVE_UID16
2907 select OLD_SIGSUSPEND3
2908
e279b6c1 2909config COMPAT
3c2362e6 2910 def_bool y
0bf62763 2911 depends on IA32_EMULATION || X86_X32
e279b6c1 2912
3120e25e 2913if COMPAT
e279b6c1 2914config COMPAT_FOR_U64_ALIGNMENT
3120e25e 2915 def_bool y
e279b6c1
SR
2916
2917config SYSVIPC_COMPAT
3c2362e6 2918 def_bool y
3120e25e 2919 depends on SYSVIPC
3120e25e 2920endif
ee009e4a 2921
e279b6c1
SR
2922endmenu
2923
2924
e5beae16
KP
2925config HAVE_ATOMIC_IOMAP
2926 def_bool y
2927 depends on X86_32
2928
4692d77f
AR
2929config X86_DEV_DMA_OPS
2930 bool
83125a3a 2931 depends on X86_64 || STA2X11
4692d77f 2932
f7219a53
AR
2933config X86_DMA_REMAP
2934 bool
83125a3a 2935 depends on STA2X11
f7219a53 2936
e585513b
KS
2937config HAVE_GENERIC_GUP
2938 def_bool y
2939
e279b6c1
SR
2940source "net/Kconfig"
2941
2942source "drivers/Kconfig"
2943
2944source "drivers/firmware/Kconfig"
2945
2946source "fs/Kconfig"
2947
e279b6c1
SR
2948source "arch/x86/Kconfig.debug"
2949
2950source "security/Kconfig"
2951
2952source "crypto/Kconfig"
2953
edf88417
AK
2954source "arch/x86/kvm/Kconfig"
2955
e279b6c1 2956source "lib/Kconfig"