x86: Introduce and use MP IRQ trigger and polarity defines
[linux-2.6-block.git] / arch / x86 / Kconfig
CommitLineData
b2441318 1# SPDX-License-Identifier: GPL-2.0
daa93fab
SR
2# Select 32 or 64 bit
3config 64BIT
6840999b 4 bool "64-bit kernel" if ARCH = "x86"
ffee0de4 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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JB
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
31 select X86_DEV_DMA_OPS
1032c0ba 32
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IM
33#
34# Arch settings
35#
36# ( Note that options that are marked 'if X86_64' could in principle be
37# ported to 32-bit as well. )
38#
8d5fffb9 39config X86
3c2362e6 40 def_bool y
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IM
41 #
42 # Note: keep this list sorted alphabetically
43 #
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IM
44 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
45 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
46 select ANON_INODES
47 select ARCH_CLOCKSOURCE_DATA
48 select ARCH_DISCARD_MEMBLOCK
c763ea26 49 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
fa5b6ec9 50 select ARCH_HAS_DEBUG_VIRTUAL
21266be9 51 select ARCH_HAS_DEVMEM_IS_ALLOWED
6471b825 52 select ARCH_HAS_ELF_RANDOMIZE
72d93104 53 select ARCH_HAS_FAST_MULTIPLIER
6974f0c4 54 select ARCH_HAS_FORTIFY_SOURCE
957e3fac 55 select ARCH_HAS_GCOV_PROFILE_ALL
5c9a8750 56 select ARCH_HAS_KCOV if X86_64
c763ea26 57 select ARCH_HAS_PMEM_API if X86_64
39208aa7 58 select ARCH_HAS_REFCOUNT
0aed55af 59 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
d2852a22 60 select ARCH_HAS_SET_MEMORY
6471b825 61 select ARCH_HAS_SG_CHAIN
ad21fc4f
LA
62 select ARCH_HAS_STRICT_KERNEL_RWX
63 select ARCH_HAS_STRICT_MODULE_RWX
c6d30853 64 select ARCH_HAS_UBSAN_SANITIZE_ALL
65f7d049 65 select ARCH_HAS_ZONE_DEVICE if X86_64
6471b825
IM
66 select ARCH_HAVE_NMI_SAFE_CMPXCHG
67 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
77fbbc81 68 select ARCH_MIGHT_HAVE_PC_PARPORT
5e2c18c0 69 select ARCH_MIGHT_HAVE_PC_SERIO
6471b825 70 select ARCH_SUPPORTS_ATOMIC_RMW
3b242c66 71 select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
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IM
72 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
73 select ARCH_USE_BUILTIN_BSWAP
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74 select ARCH_USE_QUEUED_RWLOCKS
75 select ARCH_USE_QUEUED_SPINLOCKS
ce4a4e56 76 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
c763ea26 77 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
38d8b4e6 78 select ARCH_WANTS_THP_SWAP if X86_64
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IM
79 select BUILDTIME_EXTABLE_SORT
80 select CLKEVT_I8253
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IM
81 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
82 select CLOCKSOURCE_WATCHDOG
6471b825 83 select DCACHE_WORD_ACCESS
45471cd9
LT
84 select EDAC_ATOMIC_SCRUB
85 select EDAC_SUPPORT
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IM
86 select GENERIC_CLOCKEVENTS
87 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
88 select GENERIC_CLOCKEVENTS_MIN_ADJUST
89 select GENERIC_CMOS_UPDATE
90 select GENERIC_CPU_AUTOPROBE
5b7c73e0 91 select GENERIC_EARLY_IOREMAP
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IM
92 select GENERIC_FIND_FIRST_BIT
93 select GENERIC_IOMAP
c7d6c9dd 94 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
0fa115da 95 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
ad7a929f 96 select GENERIC_IRQ_MIGRATION if SMP
6471b825 97 select GENERIC_IRQ_PROBE
c201c917 98 select GENERIC_IRQ_RESERVATION_MODE
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IM
99 select GENERIC_IRQ_SHOW
100 select GENERIC_PENDING_IRQ if SMP
101 select GENERIC_SMP_IDLE_THREAD
102 select GENERIC_STRNCPY_FROM_USER
103 select GENERIC_STRNLEN_USER
104 select GENERIC_TIME_VSYSCALL
7edaeb68 105 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
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IM
106 select HAVE_ACPI_APEI if ACPI
107 select HAVE_ACPI_APEI_NMI if ACPI
108 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
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IM
109 select HAVE_ARCH_AUDITSYSCALL
110 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
111 select HAVE_ARCH_JUMP_LABEL
d17a1d97 112 select HAVE_ARCH_KASAN if X86_64
6471b825 113 select HAVE_ARCH_KGDB
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DC
114 select HAVE_ARCH_MMAP_RND_BITS if MMU
115 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
1b028f78 116 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
6471b825 117 select HAVE_ARCH_SECCOMP_FILTER
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IM
118 select HAVE_ARCH_TRACEHOOK
119 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
a00cc7d9 120 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
e37e43a4 121 select HAVE_ARCH_VMAP_STACK if X86_64
c763ea26 122 select HAVE_ARCH_WITHIN_STACK_FRAMES
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IM
123 select HAVE_CC_STACKPROTECTOR
124 select HAVE_CMPXCHG_DOUBLE
125 select HAVE_CMPXCHG_LOCAL
126 select HAVE_CONTEXT_TRACKING if X86_64
c1bd55f9 127 select HAVE_COPY_THREAD_TLS
cf4db259 128 select HAVE_C_RECORDMCOUNT
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IM
129 select HAVE_DEBUG_KMEMLEAK
130 select HAVE_DEBUG_STACKOVERFLOW
131 select HAVE_DMA_API_DEBUG
6471b825 132 select HAVE_DMA_CONTIGUOUS
677aa9f7 133 select HAVE_DYNAMIC_FTRACE
06aeaaea 134 select HAVE_DYNAMIC_FTRACE_WITH_REGS
c763ea26 135 select HAVE_EBPF_JIT if X86_64
58340a07 136 select HAVE_EFFICIENT_UNALIGNED_ACCESS
5f56a5df 137 select HAVE_EXIT_THREAD
644e0e8d 138 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
6471b825 139 select HAVE_FTRACE_MCOUNT_RECORD
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IM
140 select HAVE_FUNCTION_GRAPH_TRACER
141 select HAVE_FUNCTION_TRACER
6b90bd4b 142 select HAVE_GCC_PLUGINS
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IM
143 select HAVE_HW_BREAKPOINT
144 select HAVE_IDE
145 select HAVE_IOREMAP_PROT
146 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
147 select HAVE_IRQ_TIME_ACCOUNTING
2e9f3bdd 148 select HAVE_KERNEL_BZIP2
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IM
149 select HAVE_KERNEL_GZIP
150 select HAVE_KERNEL_LZ4
2e9f3bdd 151 select HAVE_KERNEL_LZMA
13510997 152 select HAVE_KERNEL_LZO
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IM
153 select HAVE_KERNEL_XZ
154 select HAVE_KPROBES
155 select HAVE_KPROBES_ON_FTRACE
156 select HAVE_KRETPROBES
157 select HAVE_KVM
158 select HAVE_LIVEPATCH if X86_64
159 select HAVE_MEMBLOCK
160 select HAVE_MEMBLOCK_NODE_MAP
0102752e 161 select HAVE_MIXED_BREAKPOINTS_REGS
ee9f8fce 162 select HAVE_MOD_ARCH_SPECIFIC
42a0bb3f 163 select HAVE_NMI
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IM
164 select HAVE_OPROFILE
165 select HAVE_OPTPROBES
166 select HAVE_PCSPKR_PLATFORM
167 select HAVE_PERF_EVENTS
c01d4323 168 select HAVE_PERF_EVENTS_NMI
92e5aae4 169 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
c5e63197 170 select HAVE_PERF_REGS
c5ebcedb 171 select HAVE_PERF_USER_STACK_DUMP
9e52fc2b 172 select HAVE_RCU_TABLE_FREE
6471b825 173 select HAVE_REGS_AND_STACK_ACCESS_API
11af8474 174 select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
c763ea26 175 select HAVE_STACK_VALIDATION if X86_64
6471b825 176 select HAVE_SYSCALL_TRACEPOINTS
6471b825 177 select HAVE_UNSTABLE_SCHED_CLOCK
7c68af6e 178 select HAVE_USER_RETURN_NOTIFIER
c0185808 179 select IRQ_FORCED_THREADING
df65c1bc 180 select PCI_LOCKLESS_CONFIG
6471b825 181 select PERF_EVENTS
3195ef59 182 select RTC_LIB
d6faca40 183 select RTC_MC146818_LIB
6471b825 184 select SPARSE_IRQ
83fe27ea 185 select SRCU
6471b825 186 select SYSCTL_EXCEPTION_TRACE
15f4eae7 187 select THREAD_INFO_IN_TASK
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IM
188 select USER_STACKTRACE_SUPPORT
189 select VIRT_TO_BUS
6471b825 190 select X86_FEATURE_NAMES if PROC_FS
7d8330a5 191
ba7e4d13 192config INSTRUCTION_DECODER
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JB
193 def_bool y
194 depends on KPROBES || PERF_EVENTS || UPROBES
ba7e4d13 195
51b26ada
LT
196config OUTPUT_FORMAT
197 string
198 default "elf32-i386" if X86_32
199 default "elf64-x86-64" if X86_64
200
73531905 201config ARCH_DEFCONFIG
b9b39bfb 202 string
73531905
SR
203 default "arch/x86/configs/i386_defconfig" if X86_32
204 default "arch/x86/configs/x86_64_defconfig" if X86_64
b9b39bfb 205
8d5fffb9 206config LOCKDEP_SUPPORT
3c2362e6 207 def_bool y
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SR
208
209config STACKTRACE_SUPPORT
3c2362e6 210 def_bool y
8d5fffb9 211
8d5fffb9 212config MMU
3c2362e6 213 def_bool y
8d5fffb9 214
9e08f57d
DC
215config ARCH_MMAP_RND_BITS_MIN
216 default 28 if 64BIT
217 default 8
218
219config ARCH_MMAP_RND_BITS_MAX
220 default 32 if 64BIT
221 default 16
222
223config ARCH_MMAP_RND_COMPAT_BITS_MIN
224 default 8
225
226config ARCH_MMAP_RND_COMPAT_BITS_MAX
227 default 16
228
8d5fffb9
SR
229config SBUS
230 bool
231
3bc4e459 232config NEED_DMA_MAP_STATE
3120e25e 233 def_bool y
a6dfa128 234 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
3bc4e459 235
18e98307 236config NEED_SG_DMA_LENGTH
4a14d84e 237 def_bool y
18e98307 238
8d5fffb9 239config GENERIC_ISA_DMA
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JB
240 def_bool y
241 depends on ISA_DMA_API
8d5fffb9 242
8d5fffb9 243config GENERIC_BUG
3c2362e6 244 def_bool y
8d5fffb9 245 depends on BUG
b93a531e
JB
246 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
247
248config GENERIC_BUG_RELATIVE_POINTERS
249 bool
8d5fffb9
SR
250
251config GENERIC_HWEIGHT
3c2362e6 252 def_bool y
8d5fffb9
SR
253
254config ARCH_MAY_HAVE_PC_FDC
3120e25e
JB
255 def_bool y
256 depends on ISA_DMA_API
8d5fffb9 257
1032c0ba 258config RWSEM_XCHGADD_ALGORITHM
3120e25e 259 def_bool y
1032c0ba 260
1032c0ba
SR
261config GENERIC_CALIBRATE_DELAY
262 def_bool y
263
9a0b8415 264config ARCH_HAS_CPU_RELAX
265 def_bool y
266
1b27d05b
PE
267config ARCH_HAS_CACHE_LINE_SIZE
268 def_bool y
269
dd5af90a 270config HAVE_SETUP_PER_CPU_AREA
89c9c4c5 271 def_bool y
b32ef636 272
08fc4580
TH
273config NEED_PER_CPU_EMBED_FIRST_CHUNK
274 def_bool y
275
276config NEED_PER_CPU_PAGE_FIRST_CHUNK
11124411
TH
277 def_bool y
278
801e4062
JB
279config ARCH_HIBERNATION_POSSIBLE
280 def_bool y
801e4062 281
f4cb5700
JB
282config ARCH_SUSPEND_POSSIBLE
283 def_bool y
f4cb5700 284
cfe28c5d
SC
285config ARCH_WANT_HUGE_PMD_SHARE
286 def_bool y
287
53313b2c
SC
288config ARCH_WANT_GENERAL_HUGETLB
289 def_bool y
290
8d5fffb9 291config ZONE_DMA32
e0fd24a3 292 def_bool y if X86_64
8d5fffb9 293
8d5fffb9 294config AUDIT_ARCH
e0fd24a3 295 def_bool y if X86_64
8d5fffb9 296
765c68bd
IM
297config ARCH_SUPPORTS_OPTIMIZED_INLINING
298 def_bool y
299
6a11f75b
AM
300config ARCH_SUPPORTS_DEBUG_PAGEALLOC
301 def_bool y
302
d6f2d75a
AR
303config KASAN_SHADOW_OFFSET
304 hex
305 depends on KASAN
306 default 0xdffffc0000000000
307
69575d38
SW
308config HAVE_INTEL_TXT
309 def_bool y
6ea30386 310 depends on INTEL_IOMMU && ACPI
69575d38 311
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SR
312config X86_32_SMP
313 def_bool y
314 depends on X86_32 && SMP
315
316config X86_64_SMP
317 def_bool y
318 depends on X86_64 && SMP
319
ccbeed3a
TH
320config X86_32_LAZY_GS
321 def_bool y
60a5317f 322 depends on X86_32 && !CC_STACKPROTECTOR
ccbeed3a 323
2b144498
SD
324config ARCH_SUPPORTS_UPROBES
325 def_bool y
326
d20642f0
RH
327config FIX_EARLYCON_MEM
328 def_bool y
329
98233368
KS
330config PGTABLE_LEVELS
331 int
77ef56e4 332 default 5 if X86_5LEVEL
98233368
KS
333 default 4 if X86_64
334 default 3 if X86_PAE
335 default 2
336
506f1d07 337source "init/Kconfig"
dc52ddc0 338source "kernel/Kconfig.freezer"
8d5fffb9 339
506f1d07
SR
340menu "Processor type and features"
341
5ee71535
RD
342config ZONE_DMA
343 bool "DMA memory allocation support" if EXPERT
344 default y
345 help
346 DMA memory allocation support allows devices with less than 32-bit
347 addressing to allocate within the first 16MB of address space.
348 Disable if no such devices will be used.
349
350 If unsure, say Y.
351
506f1d07
SR
352config SMP
353 bool "Symmetric multi-processing support"
354 ---help---
355 This enables support for systems with more than one CPU. If you have
4a474157
RG
356 a system with only one CPU, say N. If you have a system with more
357 than one CPU, say Y.
506f1d07 358
4a474157 359 If you say N here, the kernel will run on uni- and multiprocessor
506f1d07
SR
360 machines, but will use only one CPU of a multiprocessor machine. If
361 you say Y here, the kernel will run on many, but not all,
4a474157 362 uniprocessor machines. On a uniprocessor machine, the kernel
506f1d07
SR
363 will run faster if you say N here.
364
365 Note that if you say Y here and choose architecture "586" or
366 "Pentium" under "Processor family", the kernel will not work on 486
367 architectures. Similarly, multiprocessor kernels for the "PPro"
368 architecture may not work on all Pentium based boards.
369
370 People using multiprocessor machines who say Y here should also say
371 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
372 Management" code will be disabled if you say Y here.
373
395cf969 374 See also <file:Documentation/x86/i386/IO-APIC.txt>,
c9525a3f 375 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
506f1d07
SR
376 <http://www.tldp.org/docs.html#howto>.
377
378 If you don't know what to do here, say N.
379
9def39be
JT
380config X86_FEATURE_NAMES
381 bool "Processor feature human-readable names" if EMBEDDED
382 default y
383 ---help---
384 This option compiles in a table of x86 feature bits and corresponding
385 names. This is required to support /proc/cpuinfo and a few kernel
386 messages. You can disable this to save space, at the expense of
387 making those few kernel messages show numeric feature bits instead.
388
389 If in doubt, say Y.
390
6e1315fe
BP
391config X86_FAST_FEATURE_TESTS
392 bool "Fast CPU feature tests" if EMBEDDED
393 default y
394 ---help---
395 Some fast-paths in the kernel depend on the capabilities of the CPU.
396 Say Y here for the kernel to patch in the appropriate code at runtime
397 based on the capabilities of the CPU. The infrastructure for patching
398 code at runtime takes up some additional space; space-constrained
399 embedded systems may wish to say N here to produce smaller, slightly
400 slower code.
401
06cd9a7d
YL
402config X86_X2APIC
403 bool "Support x2apic"
19e3d60d 404 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
06cd9a7d
YL
405 ---help---
406 This enables x2apic support on CPUs that have this feature.
407
408 This allows 32-bit apic IDs (so it can support very large systems),
409 and accesses the local apic via MSRs not via mmio.
410
06cd9a7d
YL
411 If you don't know what to do here, say N.
412
6695c85b 413config X86_MPPARSE
6e87f9b7 414 bool "Enable MPS table" if ACPI || SFI
7a527688 415 default y
5ab74722 416 depends on X86_LOCAL_APIC
8f9ca475 417 ---help---
6695c85b
YL
418 For old smp systems that do not have proper acpi support. Newer systems
419 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
6695c85b 420
26f7ef14
YL
421config X86_BIGSMP
422 bool "Support for big SMP systems with more than 8 CPUs"
423 depends on X86_32 && SMP
8f9ca475 424 ---help---
26f7ef14 425 This option is needed for the systems that have more than 8 CPUs
506f1d07 426
ddd70cf9
JN
427config GOLDFISH
428 def_bool y
429 depends on X86_GOLDFISH
430
f01d7d51
VS
431config INTEL_RDT
432 bool "Intel Resource Director Technology support"
78e99b4a
FY
433 default n
434 depends on X86 && CPU_SUP_INTEL
59fe5a77 435 select KERNFS
78e99b4a 436 help
f01d7d51
VS
437 Select to enable resource allocation and monitoring which are
438 sub-features of Intel Resource Director Technology(RDT). More
439 information about RDT can be found in the Intel x86
440 Architecture Software Developer Manual.
78e99b4a
FY
441
442 Say N if unsure.
443
8425091f 444if X86_32
c5c606d9
RT
445config X86_EXTENDED_PLATFORM
446 bool "Support for extended (non-PC) x86 platforms"
447 default y
8f9ca475 448 ---help---
06ac8346
IM
449 If you disable this option then the kernel will only support
450 standard PC platforms. (which covers the vast majority of
451 systems out there.)
452
8425091f
RT
453 If you enable this option then you'll be able to select support
454 for the following (non-PC) 32 bit x86 platforms:
cb7b8023 455 Goldfish (Android emulator)
8425091f 456 AMD Elan
8425091f
RT
457 RDC R-321x SoC
458 SGI 320/540 (Visual Workstation)
83125a3a 459 STA2X11-based (e.g. Northville)
3f4110a4 460 Moorestown MID devices
06ac8346
IM
461
462 If you have one of these systems, or if you want to build a
463 generic distribution kernel, say Y here - otherwise say N.
8425091f 464endif
06ac8346 465
8425091f
RT
466if X86_64
467config X86_EXTENDED_PLATFORM
468 bool "Support for extended (non-PC) x86 platforms"
469 default y
470 ---help---
471 If you disable this option then the kernel will only support
472 standard PC platforms. (which covers the vast majority of
473 systems out there.)
474
475 If you enable this option then you'll be able to select support
476 for the following (non-PC) 64 bit x86 platforms:
44b111b5 477 Numascale NumaChip
8425091f
RT
478 ScaleMP vSMP
479 SGI Ultraviolet
480
481 If you have one of these systems, or if you want to build a
482 generic distribution kernel, say Y here - otherwise say N.
483endif
c5c606d9
RT
484# This is an alphabetically sorted list of 64 bit extended platforms
485# Please maintain the alphabetic order if and when there are additions
44b111b5
SP
486config X86_NUMACHIP
487 bool "Numascale NumaChip"
488 depends on X86_64
489 depends on X86_EXTENDED_PLATFORM
490 depends on NUMA
491 depends on SMP
492 depends on X86_X2APIC
f9726bfd 493 depends on PCI_MMCONFIG
44b111b5
SP
494 ---help---
495 Adds support for Numascale NumaChip large-SMP systems. Needed to
496 enable more than ~168 cores.
497 If you don't have one of these, you should say N here.
506f1d07 498
c5c606d9
RT
499config X86_VSMP
500 bool "ScaleMP vSMP"
6276a074 501 select HYPERVISOR_GUEST
c5c606d9
RT
502 select PARAVIRT
503 depends on X86_64 && PCI
504 depends on X86_EXTENDED_PLATFORM
ead91d4b 505 depends on SMP
8f9ca475 506 ---help---
c5c606d9
RT
507 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
508 supposed to run on these EM64T-based machines. Only choose this option
509 if you have one of these machines.
5e3a77e9 510
03b48632
NP
511config X86_UV
512 bool "SGI Ultraviolet"
513 depends on X86_64
c5c606d9 514 depends on X86_EXTENDED_PLATFORM
54c28d29 515 depends on NUMA
1ecb4ae5 516 depends on EFI
9d6c26e7 517 depends on X86_X2APIC
1222e564 518 depends on PCI
8f9ca475 519 ---help---
03b48632
NP
520 This option is needed in order to support SGI Ultraviolet systems.
521 If you don't have one of these, you should say N here.
522
c5c606d9
RT
523# Following is an alphabetically sorted list of 32 bit extended platforms
524# Please maintain the alphabetic order if and when there are additions
506f1d07 525
ddd70cf9
JN
526config X86_GOLDFISH
527 bool "Goldfish (Virtual Platform)"
cb7b8023 528 depends on X86_EXTENDED_PLATFORM
ddd70cf9
JN
529 ---help---
530 Enable support for the Goldfish virtual platform used primarily
531 for Android development. Unless you are building for the Android
532 Goldfish emulator say N here.
533
c751e17b
TG
534config X86_INTEL_CE
535 bool "CE4100 TV platform"
536 depends on PCI
537 depends on PCI_GODIRECT
6084a6e2 538 depends on X86_IO_APIC
c751e17b
TG
539 depends on X86_32
540 depends on X86_EXTENDED_PLATFORM
37bc9f50 541 select X86_REBOOTFIXUPS
da6b737b
SAS
542 select OF
543 select OF_EARLY_FLATTREE
c751e17b
TG
544 ---help---
545 Select for the Intel CE media processor (CE4100) SOC.
546 This option compiles in support for the CE4100 SOC for settop
547 boxes and media devices.
548
4cb9b00f 549config X86_INTEL_MID
43605ef1 550 bool "Intel MID platform support"
43605ef1 551 depends on X86_EXTENDED_PLATFORM
edc6bc78 552 depends on X86_PLATFORM_DEVICES
1ea7c673 553 depends on PCI
3fda5bb4 554 depends on X86_64 || (PCI_GOANY && X86_32)
1ea7c673 555 depends on X86_IO_APIC
7c9c3a1e 556 select SFI
4cb9b00f 557 select I2C
7c9c3a1e 558 select DW_APB_TIMER
1ea7c673 559 select APB_TIMER
1ea7c673 560 select INTEL_SCU_IPC
15a713df 561 select MFD_INTEL_MSIC
1ea7c673 562 ---help---
4cb9b00f
DC
563 Select to build a kernel capable of supporting Intel MID (Mobile
564 Internet Device) platform systems which do not have the PCI legacy
565 interfaces. If you are building for a PC class system say N here.
1ea7c673 566
4cb9b00f
DC
567 Intel MID platforms are based on an Intel processor and chipset which
568 consume less power than most of the x86 derivatives.
43605ef1 569
8bbc2a13
BD
570config X86_INTEL_QUARK
571 bool "Intel Quark platform support"
572 depends on X86_32
573 depends on X86_EXTENDED_PLATFORM
574 depends on X86_PLATFORM_DEVICES
575 depends on X86_TSC
576 depends on PCI
577 depends on PCI_GOANY
578 depends on X86_IO_APIC
579 select IOSF_MBI
580 select INTEL_IMR
9ab6eb51 581 select COMMON_CLK
8bbc2a13
BD
582 ---help---
583 Select to include support for Quark X1000 SoC.
584 Say Y here if you have a Quark based system such as the Arduino
585 compatible Intel Galileo.
586
3d48aab1
MW
587config X86_INTEL_LPSS
588 bool "Intel Low Power Subsystem Support"
eebb3e8d 589 depends on X86 && ACPI
3d48aab1 590 select COMMON_CLK
0f531431 591 select PINCTRL
eebb3e8d 592 select IOSF_MBI
3d48aab1
MW
593 ---help---
594 Select to build support for Intel Low Power Subsystem such as
595 found on Intel Lynxpoint PCH. Selecting this option enables
0f531431
MN
596 things like clock tree (common clock framework) and pincontrol
597 which are needed by the LPSS peripheral drivers.
3d48aab1 598
92082a88
KX
599config X86_AMD_PLATFORM_DEVICE
600 bool "AMD ACPI2Platform devices support"
601 depends on ACPI
602 select COMMON_CLK
603 select PINCTRL
604 ---help---
605 Select to interpret AMD specific ACPI device to platform device
606 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
607 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
608 implemented under PINCTRL subsystem.
609
ced3ce76
DB
610config IOSF_MBI
611 tristate "Intel SoC IOSF Sideband support for SoC platforms"
612 depends on PCI
613 ---help---
614 This option enables sideband register access support for Intel SoC
615 platforms. On these platforms the IOSF sideband is used in lieu of
616 MSR's for some register accesses, mostly but not limited to thermal
617 and power. Drivers may query the availability of this device to
618 determine if they need the sideband in order to work on these
619 platforms. The sideband is available on the following SoC products.
620 This list is not meant to be exclusive.
621 - BayTrail
622 - Braswell
623 - Quark
624
625 You should say Y if you are running a kernel on one of these SoC's.
626
ed2226bd
DB
627config IOSF_MBI_DEBUG
628 bool "Enable IOSF sideband access through debugfs"
629 depends on IOSF_MBI && DEBUG_FS
630 ---help---
631 Select this option to expose the IOSF sideband access registers (MCR,
632 MDR, MCRX) through debugfs to write and read register information from
633 different units on the SoC. This is most useful for obtaining device
634 state information for debug and analysis. As this is a general access
635 mechanism, users of this option would have specific knowledge of the
636 device they want to access.
637
638 If you don't require the option or are in doubt, say N.
639
c5c606d9
RT
640config X86_RDC321X
641 bool "RDC R-321x SoC"
506f1d07 642 depends on X86_32
c5c606d9
RT
643 depends on X86_EXTENDED_PLATFORM
644 select M486
645 select X86_REBOOTFIXUPS
646 ---help---
647 This option is needed for RDC R-321x system-on-chip, also known
648 as R-8610-(G).
649 If you don't have one of these chips, you should say N here.
650
e0c7ae37 651config X86_32_NON_STANDARD
9c398017
IM
652 bool "Support non-standard 32-bit SMP architectures"
653 depends on X86_32 && SMP
c5c606d9 654 depends on X86_EXTENDED_PLATFORM
8f9ca475 655 ---help---
b5660ba7
PA
656 This option compiles in the bigsmp and STA2X11 default
657 subarchitectures. It is intended for a generic binary
658 kernel. If you select them all, kernel will probe it one by
659 one and will fallback to default.
d49c4288 660
c5c606d9 661# Alphabetically sorted list of Non standard 32 bit platforms
d49c4288 662
d949f36f 663config X86_SUPPORTS_MEMORY_FAILURE
6fc108a0 664 def_bool y
d949f36f
LT
665 # MCE code calls memory_failure():
666 depends on X86_MCE
667 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
d949f36f
LT
668 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
669 depends on X86_64 || !SPARSEMEM
670 select ARCH_SUPPORTS_MEMORY_FAILURE
d949f36f 671
83125a3a
AR
672config STA2X11
673 bool "STA2X11 Companion Chip Support"
674 depends on X86_32_NON_STANDARD && PCI
675 select X86_DEV_DMA_OPS
676 select X86_DMA_REMAP
677 select SWIOTLB
678 select MFD_STA2X11
0145071b 679 select GPIOLIB
83125a3a
AR
680 default n
681 ---help---
682 This adds support for boards based on the STA2X11 IO-Hub,
683 a.k.a. "ConneXt". The chip is used in place of the standard
684 PC chipset, so all "standard" peripherals are missing. If this
685 option is selected the kernel will still be able to boot on
686 standard PC machines.
687
82148d1d
S
688config X86_32_IRIS
689 tristate "Eurobraille/Iris poweroff module"
690 depends on X86_32
691 ---help---
692 The Iris machines from EuroBraille do not have APM or ACPI support
693 to shut themselves down properly. A special I/O sequence is
694 needed to do so, which is what this module does at
695 kernel shutdown.
696
697 This is only for Iris machines from EuroBraille.
698
699 If unused, say N.
700
ae1e9130 701config SCHED_OMIT_FRAME_POINTER
3c2362e6
HH
702 def_bool y
703 prompt "Single-depth WCHAN output"
a87d0914 704 depends on X86
8f9ca475 705 ---help---
506f1d07
SR
706 Calculate simpler /proc/<PID>/wchan values. If this option
707 is disabled then wchan values will recurse back to the
708 caller function. This provides more accurate wchan values,
709 at the expense of slightly more scheduling overhead.
710
711 If in doubt, say "Y".
712
6276a074
BP
713menuconfig HYPERVISOR_GUEST
714 bool "Linux guest support"
8f9ca475 715 ---help---
6276a074
BP
716 Say Y here to enable options for running Linux under various hyper-
717 visors. This option enables basic hypervisor detection and platform
718 setup.
506f1d07 719
6276a074
BP
720 If you say N, all options in this submenu will be skipped and
721 disabled, and Linux guest support won't be built in.
506f1d07 722
6276a074 723if HYPERVISOR_GUEST
506f1d07 724
e61bd94a
EPH
725config PARAVIRT
726 bool "Enable paravirtualization code"
8f9ca475 727 ---help---
e61bd94a
EPH
728 This changes the kernel so it can modify itself when it is run
729 under a hypervisor, potentially improving performance significantly
730 over full virtualization. However, when run without a hypervisor
731 the kernel is theoretically slower and slightly larger.
732
6276a074
BP
733config PARAVIRT_DEBUG
734 bool "paravirt-ops debugging"
735 depends on PARAVIRT && DEBUG_KERNEL
736 ---help---
737 Enable to debug paravirt_ops internals. Specifically, BUG if
738 a paravirt_op is missing when it is called.
739
b4ecc126
JF
740config PARAVIRT_SPINLOCKS
741 bool "Paravirtualization layer for spinlocks"
6ea30386 742 depends on PARAVIRT && SMP
b4ecc126
JF
743 ---help---
744 Paravirtualized spinlocks allow a pvops backend to replace the
745 spinlock implementation with something virtualization-friendly
746 (for example, block the virtual CPU rather than spinning).
747
4c4e4f61
R
748 It has a minimal impact on native kernels and gives a nice performance
749 benefit on paravirtualized KVM / Xen kernels.
b4ecc126 750
4c4e4f61 751 If you are unsure how to answer this question, answer Y.
b4ecc126 752
45e898b7
WL
753config QUEUED_LOCK_STAT
754 bool "Paravirt queued spinlock statistics"
cfd8983f 755 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
45e898b7
WL
756 ---help---
757 Enable the collection of statistical data on the slowpath
758 behavior of paravirtualized queued spinlocks and report
759 them on debugfs.
760
6276a074 761source "arch/x86/xen/Kconfig"
7af192c9 762
6276a074
BP
763config KVM_GUEST
764 bool "KVM Guest support (including kvmclock)"
765 depends on PARAVIRT
766 select PARAVIRT_CLOCK
767 default y
8f9ca475 768 ---help---
6276a074
BP
769 This option enables various optimizations for running under the KVM
770 hypervisor. It includes a paravirtualized clock, so that instead
771 of relying on a PIT (or probably other) emulation by the
772 underlying device model, the host provides the guest with
773 timing infrastructure such as time of day, and system time
506f1d07 774
1e20eb85
SV
775config KVM_DEBUG_FS
776 bool "Enable debug information for KVM Guests in debugfs"
777 depends on KVM_GUEST && DEBUG_FS
778 default n
779 ---help---
780 This option enables collection of various statistics for KVM guest.
781 Statistics are displayed in debugfs filesystem. Enabling this option
782 may incur significant overhead.
783
6276a074
BP
784config PARAVIRT_TIME_ACCOUNTING
785 bool "Paravirtual steal time accounting"
786 depends on PARAVIRT
787 default n
8f9ca475 788 ---help---
6276a074
BP
789 Select this option to enable fine granularity task steal time
790 accounting. Time spent executing other tasks in parallel with
791 the current vCPU is discounted from the vCPU power. To account for
792 that, there can be a small performance impact.
793
794 If in doubt, say N here.
795
796config PARAVIRT_CLOCK
797 bool
97349135 798
6276a074 799endif #HYPERVISOR_GUEST
97349135 800
08677214 801config NO_BOOTMEM
774ea0bc 802 def_bool y
08677214 803
506f1d07
SR
804source "arch/x86/Kconfig.cpu"
805
806config HPET_TIMER
3c2362e6 807 def_bool X86_64
506f1d07 808 prompt "HPET Timer Support" if X86_32
8f9ca475
IM
809 ---help---
810 Use the IA-PC HPET (High Precision Event Timer) to manage
811 time in preference to the PIT and RTC, if a HPET is
812 present.
813 HPET is the next generation timer replacing legacy 8254s.
814 The HPET provides a stable time base on SMP
815 systems, unlike the TSC, but it is more expensive to access,
4e7f9df2
MT
816 as it is off-chip. The interface used is documented
817 in the HPET spec, revision 1.
506f1d07 818
8f9ca475
IM
819 You can safely choose Y here. However, HPET will only be
820 activated if the platform and the BIOS support this feature.
821 Otherwise the 8254 will be used for timing services.
506f1d07 822
8f9ca475 823 Choose N to continue using the legacy 8254 timer.
506f1d07
SR
824
825config HPET_EMULATE_RTC
3c2362e6 826 def_bool y
9d8af78b 827 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
506f1d07 828
bb24c471 829config APB_TIMER
933b9463
AC
830 def_bool y if X86_INTEL_MID
831 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
06c3df49 832 select DW_APB_TIMER
a0c3832a 833 depends on X86_INTEL_MID && SFI
bb24c471
JP
834 help
835 APB timer is the replacement for 8254, HPET on X86 MID platforms.
836 The APBT provides a stable time base on SMP
837 systems, unlike the TSC, but it is more expensive to access,
838 as it is off-chip. APB timers are always running regardless of CPU
839 C states, they are used as per CPU clockevent device when possible.
840
6a108a14 841# Mark as expert because too many people got it wrong.
506f1d07 842# The code disables itself when not needed.
7ae9392c
TP
843config DMI
844 default y
cf074402 845 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
6a108a14 846 bool "Enable DMI scanning" if EXPERT
8f9ca475 847 ---help---
7ae9392c
TP
848 Enabled scanning of DMI to identify machine quirks. Say Y
849 here unless you have verified that your setup is not
850 affected by entries in the DMI blacklist. Required by PNP
851 BIOS code.
852
506f1d07 853config GART_IOMMU
38901f1c 854 bool "Old AMD GART IOMMU support"
506f1d07 855 select SWIOTLB
23ac4ae8 856 depends on X86_64 && PCI && AMD_NB
8f9ca475 857 ---help---
ced3c42c
IM
858 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
859 GART based hardware IOMMUs.
860
861 The GART supports full DMA access for devices with 32-bit access
862 limitations, on systems with more than 3 GB. This is usually needed
863 for USB, sound, many IDE/SATA chipsets and some other devices.
864
865 Newer systems typically have a modern AMD IOMMU, supported via
866 the CONFIG_AMD_IOMMU=y config option.
867
868 In normal configurations this driver is only active when needed:
869 there's more than 3 GB of memory and the system contains a
870 32-bit limited device.
871
872 If unsure, say Y.
506f1d07
SR
873
874config CALGARY_IOMMU
875 bool "IBM Calgary IOMMU support"
876 select SWIOTLB
6ea30386 877 depends on X86_64 && PCI
8f9ca475 878 ---help---
506f1d07
SR
879 Support for hardware IOMMUs in IBM's xSeries x366 and x460
880 systems. Needed to run systems with more than 3GB of memory
881 properly with 32-bit PCI devices that do not support DAC
882 (Double Address Cycle). Calgary also supports bus level
883 isolation, where all DMAs pass through the IOMMU. This
884 prevents them from going anywhere except their intended
885 destination. This catches hard-to-find kernel bugs and
886 mis-behaving drivers and devices that do not use the DMA-API
887 properly to set up their DMA buffers. The IOMMU can be
888 turned off at boot time with the iommu=off parameter.
889 Normally the kernel will make the right choice by itself.
890 If unsure, say Y.
891
892config CALGARY_IOMMU_ENABLED_BY_DEFAULT
3c2362e6
HH
893 def_bool y
894 prompt "Should Calgary be enabled by default?"
506f1d07 895 depends on CALGARY_IOMMU
8f9ca475 896 ---help---
506f1d07
SR
897 Should Calgary be enabled by default? if you choose 'y', Calgary
898 will be used (if it exists). If you choose 'n', Calgary will not be
899 used even if it exists. If you choose 'n' and would like to use
900 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
901 If unsure, say Y.
902
903# need this always selected by IOMMU for the VIA workaround
904config SWIOTLB
a1afd01c 905 def_bool y if X86_64
8f9ca475 906 ---help---
506f1d07 907 Support for software bounce buffers used on x86-64 systems
4454d327
JM
908 which don't have a hardware IOMMU. Using this PCI devices
909 which can only access 32-bits of memory can be used on systems
910 with more than 3 GB of memory.
911 If unsure, say Y.
506f1d07 912
a8522509 913config IOMMU_HELPER
3120e25e
JB
914 def_bool y
915 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
d25e26b6 916
1184dc2f 917config MAXSMP
ddb0c5a6 918 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
6ea30386 919 depends on X86_64 && SMP && DEBUG_KERNEL
36f5101a 920 select CPUMASK_OFFSTACK
8f9ca475 921 ---help---
ddb0c5a6 922 Enable maximum number of CPUS and NUMA Nodes for this architecture.
1184dc2f 923 If unsure, say N.
506f1d07
SR
924
925config NR_CPUS
36f5101a 926 int "Maximum number of CPUs" if SMP && !MAXSMP
2a3313f4 927 range 2 8 if SMP && X86_32 && !X86_BIGSMP
7bbcbd3d
TG
928 range 2 64 if SMP && X86_32 && X86_BIGSMP
929 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK && X86_64
b53b5eda 930 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
78637a97 931 default "1" if !SMP
b53b5eda 932 default "8192" if MAXSMP
b5660ba7 933 default "32" if SMP && X86_BIGSMP
c5c19941
KS
934 default "8" if SMP && X86_32
935 default "64" if SMP
8f9ca475 936 ---help---
506f1d07 937 This allows you to specify the maximum number of CPUs which this
bb61ccc7 938 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
cad14bb9 939 supported value is 8192, otherwise the maximum value is 512. The
506f1d07
SR
940 minimum value which makes sense is 2.
941
942 This is purely to save memory - each supported CPU adds
943 approximately eight kilobytes to the kernel image.
944
945config SCHED_SMT
946 bool "SMT (Hyperthreading) scheduler support"
c8e56d20 947 depends on SMP
8f9ca475 948 ---help---
506f1d07
SR
949 SMT scheduler support improves the CPU scheduler's decision making
950 when dealing with Intel Pentium 4 chips with HyperThreading at a
951 cost of slightly increased overhead in some places. If unsure say
952 N here.
953
954config SCHED_MC
3c2362e6
HH
955 def_bool y
956 prompt "Multi-core scheduler support"
c8e56d20 957 depends on SMP
8f9ca475 958 ---help---
506f1d07
SR
959 Multi-core scheduler support improves the CPU scheduler's decision
960 making when dealing with multi-core CPU chips at a cost of slightly
961 increased overhead in some places. If unsure say N here.
962
de966cf4
TC
963config SCHED_MC_PRIO
964 bool "CPU core priorities scheduler support"
0a21fc12
IM
965 depends on SCHED_MC && CPU_SUP_INTEL
966 select X86_INTEL_PSTATE
967 select CPU_FREQ
de966cf4 968 default y
5e76b2ab 969 ---help---
0a21fc12
IM
970 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
971 core ordering determined at manufacturing time, which allows
972 certain cores to reach higher turbo frequencies (when running
973 single threaded workloads) than others.
de966cf4 974
0a21fc12
IM
975 Enabling this kernel feature teaches the scheduler about
976 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
977 scheduler's CPU selection logic accordingly, so that higher
978 overall system performance can be achieved.
de966cf4 979
0a21fc12 980 This feature will have no effect on CPUs without this feature.
de966cf4 981
0a21fc12 982 If unsure say Y here.
5e76b2ab 983
506f1d07
SR
984source "kernel/Kconfig.preempt"
985
30b8b006
TG
986config UP_LATE_INIT
987 def_bool y
ba360f88 988 depends on !SMP && X86_LOCAL_APIC
30b8b006 989
506f1d07 990config X86_UP_APIC
50849eef
JB
991 bool "Local APIC support on uniprocessors" if !PCI_MSI
992 default PCI_MSI
38a1dfda 993 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
8f9ca475 994 ---help---
506f1d07
SR
995 A local APIC (Advanced Programmable Interrupt Controller) is an
996 integrated interrupt controller in the CPU. If you have a single-CPU
997 system which has a processor with a local APIC, you can say Y here to
998 enable and use it. If you say Y here even though your machine doesn't
999 have a local APIC, then the kernel will still run with no slowdown at
1000 all. The local APIC supports CPU-generated self-interrupts (timer,
1001 performance counters), and the NMI watchdog which detects hard
1002 lockups.
1003
1004config X86_UP_IOAPIC
1005 bool "IO-APIC support on uniprocessors"
1006 depends on X86_UP_APIC
8f9ca475 1007 ---help---
506f1d07
SR
1008 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1009 SMP-capable replacement for PC-style interrupt controllers. Most
1010 SMP systems and many recent uniprocessor systems have one.
1011
1012 If you have a single-CPU system with an IO-APIC, you can say Y here
1013 to use it. If you say Y here even though your machine doesn't have
1014 an IO-APIC, then the kernel will still run with no slowdown at all.
1015
1016config X86_LOCAL_APIC
3c2362e6 1017 def_bool y
0dbc6078 1018 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
b5dc8e6c 1019 select IRQ_DOMAIN_HIERARCHY
52f518a3 1020 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
506f1d07
SR
1021
1022config X86_IO_APIC
b1da1e71
JB
1023 def_bool y
1024 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
506f1d07 1025
41b9eb26
SA
1026config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1027 bool "Reroute for broken boot IRQs"
41b9eb26 1028 depends on X86_IO_APIC
8f9ca475 1029 ---help---
41b9eb26
SA
1030 This option enables a workaround that fixes a source of
1031 spurious interrupts. This is recommended when threaded
1032 interrupt handling is used on systems where the generation of
1033 superfluous "boot interrupts" cannot be disabled.
1034
1035 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1036 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1037 kernel does during interrupt handling). On chipsets where this
1038 boot IRQ generation cannot be disabled, this workaround keeps
1039 the original IRQ line masked so that only the equivalent "boot
1040 IRQ" is delivered to the CPUs. The workaround also tells the
1041 kernel to set up the IRQ handler on the boot IRQ line. In this
1042 way only one interrupt is delivered to the kernel. Otherwise
1043 the spurious second interrupt may cause the kernel to bring
1044 down (vital) interrupt lines.
1045
1046 Only affects "broken" chipsets. Interrupt sharing may be
1047 increased on these systems.
1048
506f1d07 1049config X86_MCE
bab9bc65 1050 bool "Machine Check / overheating reporting"
648ed940 1051 select GENERIC_ALLOCATOR
e57dbaf7 1052 default y
506f1d07 1053 ---help---
bab9bc65
AK
1054 Machine Check support allows the processor to notify the
1055 kernel if it detects a problem (e.g. overheating, data corruption).
506f1d07 1056 The action the kernel takes depends on the severity of the problem,
bab9bc65 1057 ranging from warning messages to halting the machine.
4efc0670 1058
5de97c9f
TL
1059config X86_MCELOG_LEGACY
1060 bool "Support for deprecated /dev/mcelog character device"
1061 depends on X86_MCE
1062 ---help---
1063 Enable support for /dev/mcelog which is needed by the old mcelog
1064 userspace logging daemon. Consider switching to the new generation
1065 rasdaemon solution.
1066
506f1d07 1067config X86_MCE_INTEL
3c2362e6
HH
1068 def_bool y
1069 prompt "Intel MCE features"
c1ebf835 1070 depends on X86_MCE && X86_LOCAL_APIC
8f9ca475 1071 ---help---
506f1d07
SR
1072 Additional support for intel specific MCE features such as
1073 the thermal monitor.
1074
1075config X86_MCE_AMD
3c2362e6
HH
1076 def_bool y
1077 prompt "AMD MCE features"
f5382de9 1078 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
8f9ca475 1079 ---help---
506f1d07
SR
1080 Additional support for AMD specific MCE features such as
1081 the DRAM Error Threshold.
1082
4efc0670 1083config X86_ANCIENT_MCE
6fc108a0 1084 bool "Support for old Pentium 5 / WinChip machine checks"
c31d9633 1085 depends on X86_32 && X86_MCE
cd13adcc
HS
1086 ---help---
1087 Include support for machine check handling on old Pentium 5 or WinChip
5065a706 1088 systems. These typically need to be enabled explicitly on the command
cd13adcc 1089 line.
4efc0670 1090
b2762686
AK
1091config X86_MCE_THRESHOLD
1092 depends on X86_MCE_AMD || X86_MCE_INTEL
6fc108a0 1093 def_bool y
b2762686 1094
ea149b36 1095config X86_MCE_INJECT
bc8e80d5 1096 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
ea149b36
AK
1097 tristate "Machine check injector support"
1098 ---help---
1099 Provide support for injecting machine checks for testing purposes.
1100 If you don't know what a machine check is and you don't do kernel
1101 QA it is safe to say n.
1102
4efc0670
AK
1103config X86_THERMAL_VECTOR
1104 def_bool y
5bb38adc 1105 depends on X86_MCE_INTEL
4efc0670 1106
07dc900e 1107source "arch/x86/events/Kconfig"
e633c65a 1108
5aef51c3 1109config X86_LEGACY_VM86
1e642812 1110 bool "Legacy VM86 support"
5aef51c3 1111 default n
506f1d07 1112 depends on X86_32
8f9ca475 1113 ---help---
5aef51c3
AL
1114 This option allows user programs to put the CPU into V8086
1115 mode, which is an 80286-era approximation of 16-bit real mode.
1116
1117 Some very old versions of X and/or vbetool require this option
1118 for user mode setting. Similarly, DOSEMU will use it if
1119 available to accelerate real mode DOS programs. However, any
1120 recent version of DOSEMU, X, or vbetool should be fully
1121 functional even without kernel VM86 support, as they will all
1e642812
IM
1122 fall back to software emulation. Nevertheless, if you are using
1123 a 16-bit DOS program where 16-bit performance matters, vm86
1124 mode might be faster than emulation and you might want to
1125 enable this option.
5aef51c3 1126
1e642812
IM
1127 Note that any app that works on a 64-bit kernel is unlikely to
1128 need this option, as 64-bit kernels don't, and can't, support
1129 V8086 mode. This option is also unrelated to 16-bit protected
1130 mode and is not needed to run most 16-bit programs under Wine.
5aef51c3 1131
1e642812
IM
1132 Enabling this option increases the complexity of the kernel
1133 and slows down exception handling a tiny bit.
5aef51c3 1134
1e642812 1135 If unsure, say N here.
5aef51c3
AL
1136
1137config VM86
1138 bool
1139 default X86_LEGACY_VM86
34273f41
PA
1140
1141config X86_16BIT
1142 bool "Enable support for 16-bit segments" if EXPERT
1143 default y
a5b9e5a2 1144 depends on MODIFY_LDT_SYSCALL
34273f41
PA
1145 ---help---
1146 This option is required by programs like Wine to run 16-bit
1147 protected mode legacy code on x86 processors. Disabling
1148 this option saves about 300 bytes on i386, or around 6K text
1149 plus 16K runtime memory on x86-64,
1150
1151config X86_ESPFIX32
1152 def_bool y
1153 depends on X86_16BIT && X86_32
506f1d07 1154
197725de
PA
1155config X86_ESPFIX64
1156 def_bool y
34273f41 1157 depends on X86_16BIT && X86_64
506f1d07 1158
1ad83c85
AL
1159config X86_VSYSCALL_EMULATION
1160 bool "Enable vsyscall emulation" if EXPERT
1161 default y
1162 depends on X86_64
1163 ---help---
1164 This enables emulation of the legacy vsyscall page. Disabling
1165 it is roughly equivalent to booting with vsyscall=none, except
1166 that it will also disable the helpful warning if a program
1167 tries to use a vsyscall. With this option set to N, offending
1168 programs will just segfault, citing addresses of the form
1169 0xffffffffff600?00.
1170
1171 This option is required by many programs built before 2013, and
1172 care should be used even with newer programs if set to N.
1173
1174 Disabling this option saves about 7K of kernel size and
1175 possibly 4K of additional runtime pagetable memory.
1176
506f1d07
SR
1177config TOSHIBA
1178 tristate "Toshiba Laptop support"
1179 depends on X86_32
1180 ---help---
1181 This adds a driver to safely access the System Management Mode of
1182 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1183 not work on models with a Phoenix BIOS. The System Management Mode
1184 is used to set the BIOS and power saving options on Toshiba portables.
1185
1186 For information on utilities to make use of this driver see the
1187 Toshiba Linux utilities web site at:
1188 <http://www.buzzard.org.uk/toshiba/>.
1189
1190 Say Y if you intend to run this kernel on a Toshiba portable.
1191 Say N otherwise.
1192
1193config I8K
039ae585 1194 tristate "Dell i8k legacy laptop support"
949a9d70 1195 select HWMON
039ae585 1196 select SENSORS_DELL_SMM
506f1d07 1197 ---help---
039ae585
PR
1198 This option enables legacy /proc/i8k userspace interface in hwmon
1199 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1200 temperature and allows controlling fan speeds of Dell laptops via
1201 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1202 it reports also power and hotkey status. For fan speed control is
1203 needed userspace package i8kutils.
1204
1205 Say Y if you intend to run this kernel on old Dell laptops or want to
1206 use userspace package i8kutils.
506f1d07
SR
1207 Say N otherwise.
1208
1209config X86_REBOOTFIXUPS
9ba16087
JB
1210 bool "Enable X86 board specific fixups for reboot"
1211 depends on X86_32
506f1d07
SR
1212 ---help---
1213 This enables chipset and/or board specific fixups to be done
1214 in order to get reboot to work correctly. This is only needed on
1215 some combinations of hardware and BIOS. The symptom, for which
1216 this config is intended, is when reboot ends with a stalled/hung
1217 system.
1218
1219 Currently, the only fixup is for the Geode machines using
5e3a77e9 1220 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
506f1d07
SR
1221
1222 Say Y if you want to enable the fixup. Currently, it's safe to
1223 enable this option even if you don't need it.
1224 Say N otherwise.
1225
1226config MICROCODE
9a2bc335
BP
1227 bool "CPU microcode loading support"
1228 default y
80030e3d 1229 depends on CPU_SUP_AMD || CPU_SUP_INTEL
506f1d07
SR
1230 select FW_LOADER
1231 ---help---
1232 If you say Y here, you will be able to update the microcode on
5f9c01aa
BP
1233 Intel and AMD processors. The Intel support is for the IA32 family,
1234 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1235 AMD support is for families 0x10 and later. You will obviously need
1236 the actual microcode binary data itself which is not shipped with
1237 the Linux kernel.
1238
1239 The preferred method to load microcode from a detached initrd is described
1240 in Documentation/x86/early-microcode.txt. For that you need to enable
1241 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1242 initrd for microcode blobs.
1243
1244 In addition, you can build-in the microcode into the kernel. For that you
1245 need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode
1246 to the CONFIG_EXTRA_FIRMWARE config option.
506f1d07 1247
8d86f390 1248config MICROCODE_INTEL
e43f6e67 1249 bool "Intel microcode loading support"
8f9ca475
IM
1250 depends on MICROCODE
1251 default MICROCODE
1252 select FW_LOADER
1253 ---help---
1254 This options enables microcode patch loading support for Intel
1255 processors.
1256
b8989db9
A
1257 For the current Intel microcode data package go to
1258 <https://downloadcenter.intel.com> and search for
1259 'Linux Processor Microcode Data File'.
8d86f390 1260
80cc9f10 1261config MICROCODE_AMD
e43f6e67 1262 bool "AMD microcode loading support"
8f9ca475
IM
1263 depends on MICROCODE
1264 select FW_LOADER
1265 ---help---
1266 If you select this option, microcode patch loading support for AMD
1267 processors will be enabled.
80cc9f10 1268
8f9ca475 1269config MICROCODE_OLD_INTERFACE
3c2362e6 1270 def_bool y
506f1d07 1271 depends on MICROCODE
506f1d07
SR
1272
1273config X86_MSR
1274 tristate "/dev/cpu/*/msr - Model-specific register support"
8f9ca475 1275 ---help---
506f1d07
SR
1276 This device gives privileged processes access to the x86
1277 Model-Specific Registers (MSRs). It is a character device with
1278 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1279 MSR accesses are directed to a specific CPU on multi-processor
1280 systems.
1281
1282config X86_CPUID
1283 tristate "/dev/cpu/*/cpuid - CPU information support"
8f9ca475 1284 ---help---
506f1d07
SR
1285 This device gives processes access to the x86 CPUID instruction to
1286 be executed on a specific processor. It is a character device
1287 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1288 /dev/cpu/31/cpuid.
1289
1290choice
1291 prompt "High Memory Support"
6fc108a0 1292 default HIGHMEM4G
506f1d07
SR
1293 depends on X86_32
1294
1295config NOHIGHMEM
1296 bool "off"
506f1d07
SR
1297 ---help---
1298 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1299 However, the address space of 32-bit x86 processors is only 4
1300 Gigabytes large. That means that, if you have a large amount of
1301 physical memory, not all of it can be "permanently mapped" by the
1302 kernel. The physical memory that's not permanently mapped is called
1303 "high memory".
1304
1305 If you are compiling a kernel which will never run on a machine with
1306 more than 1 Gigabyte total physical RAM, answer "off" here (default
1307 choice and suitable for most users). This will result in a "3GB/1GB"
1308 split: 3GB are mapped so that each process sees a 3GB virtual memory
1309 space and the remaining part of the 4GB virtual memory space is used
1310 by the kernel to permanently map as much physical memory as
1311 possible.
1312
1313 If the machine has between 1 and 4 Gigabytes physical RAM, then
1314 answer "4GB" here.
1315
1316 If more than 4 Gigabytes is used then answer "64GB" here. This
1317 selection turns Intel PAE (Physical Address Extension) mode on.
1318 PAE implements 3-level paging on IA32 processors. PAE is fully
1319 supported by Linux, PAE mode is implemented on all recent Intel
1320 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1321 then the kernel will not boot on CPUs that don't support PAE!
1322
1323 The actual amount of total physical memory will either be
1324 auto detected or can be forced by using a kernel command line option
1325 such as "mem=256M". (Try "man bootparam" or see the documentation of
1326 your boot loader (lilo or loadlin) about how to pass options to the
1327 kernel at boot time.)
1328
1329 If unsure, say "off".
1330
1331config HIGHMEM4G
1332 bool "4GB"
8f9ca475 1333 ---help---
506f1d07
SR
1334 Select this if you have a 32-bit processor and between 1 and 4
1335 gigabytes of physical RAM.
1336
1337config HIGHMEM64G
1338 bool "64GB"
eb068e78 1339 depends on !M486
506f1d07 1340 select X86_PAE
8f9ca475 1341 ---help---
506f1d07
SR
1342 Select this if you have a 32-bit processor and more than 4
1343 gigabytes of physical RAM.
1344
1345endchoice
1346
1347choice
6a108a14 1348 prompt "Memory split" if EXPERT
506f1d07
SR
1349 default VMSPLIT_3G
1350 depends on X86_32
8f9ca475 1351 ---help---
506f1d07
SR
1352 Select the desired split between kernel and user memory.
1353
1354 If the address range available to the kernel is less than the
1355 physical memory installed, the remaining memory will be available
1356 as "high memory". Accessing high memory is a little more costly
1357 than low memory, as it needs to be mapped into the kernel first.
1358 Note that increasing the kernel address space limits the range
1359 available to user programs, making the address space there
1360 tighter. Selecting anything other than the default 3G/1G split
1361 will also likely make your kernel incompatible with binary-only
1362 kernel modules.
1363
1364 If you are not absolutely sure what you are doing, leave this
1365 option alone!
1366
1367 config VMSPLIT_3G
1368 bool "3G/1G user/kernel split"
1369 config VMSPLIT_3G_OPT
1370 depends on !X86_PAE
1371 bool "3G/1G user/kernel split (for full 1G low memory)"
1372 config VMSPLIT_2G
1373 bool "2G/2G user/kernel split"
1374 config VMSPLIT_2G_OPT
1375 depends on !X86_PAE
1376 bool "2G/2G user/kernel split (for full 2G low memory)"
1377 config VMSPLIT_1G
1378 bool "1G/3G user/kernel split"
1379endchoice
1380
1381config PAGE_OFFSET
1382 hex
1383 default 0xB0000000 if VMSPLIT_3G_OPT
1384 default 0x80000000 if VMSPLIT_2G
1385 default 0x78000000 if VMSPLIT_2G_OPT
1386 default 0x40000000 if VMSPLIT_1G
1387 default 0xC0000000
1388 depends on X86_32
1389
1390config HIGHMEM
3c2362e6 1391 def_bool y
506f1d07 1392 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
506f1d07
SR
1393
1394config X86_PAE
9ba16087 1395 bool "PAE (Physical Address Extension) Support"
506f1d07 1396 depends on X86_32 && !HIGHMEM4G
9d99c712 1397 select SWIOTLB
8f9ca475 1398 ---help---
506f1d07
SR
1399 PAE is required for NX support, and furthermore enables
1400 larger swapspace support for non-overcommit purposes. It
1401 has the cost of more pagetable lookup overhead, and also
1402 consumes more pagetable space per process.
1403
77ef56e4
KS
1404config X86_5LEVEL
1405 bool "Enable 5-level page tables support"
1406 depends on X86_64
1407 ---help---
1408 5-level paging enables access to larger address space:
1409 upto 128 PiB of virtual address space and 4 PiB of
1410 physical address space.
1411
1412 It will be supported by future Intel CPUs.
1413
1414 Note: a kernel with this option enabled can only be booted
1415 on machines that support the feature.
1416
1417 See Documentation/x86/x86_64/5level-paging.txt for more
1418 information.
1419
1420 Say N if unsure.
1421
600715dc 1422config ARCH_PHYS_ADDR_T_64BIT
3120e25e
JB
1423 def_bool y
1424 depends on X86_64 || X86_PAE
600715dc 1425
66f2b061 1426config ARCH_DMA_ADDR_T_64BIT
3120e25e
JB
1427 def_bool y
1428 depends on X86_64 || HIGHMEM64G
66f2b061 1429
10971ab2 1430config X86_DIRECT_GBPAGES
e5008abe 1431 def_bool y
4675ff05 1432 depends on X86_64 && !DEBUG_PAGEALLOC
8f9ca475 1433 ---help---
10971ab2
IM
1434 Certain kernel features effectively disable kernel
1435 linear 1 GB mappings (even if the CPU otherwise
1436 supports them), so don't confuse the user by printing
1437 that we have them enabled.
9e899816 1438
7744ccdb
TL
1439config ARCH_HAS_MEM_ENCRYPT
1440 def_bool y
1441
1442config AMD_MEM_ENCRYPT
1443 bool "AMD Secure Memory Encryption (SME) support"
1444 depends on X86_64 && CPU_SUP_AMD
1445 ---help---
1446 Say yes to enable support for the encryption of system memory.
1447 This requires an AMD processor that supports Secure Memory
1448 Encryption (SME).
1449
1450config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1451 bool "Activate AMD Secure Memory Encryption (SME) by default"
1452 default y
1453 depends on AMD_MEM_ENCRYPT
1454 ---help---
1455 Say yes to have system memory encrypted by default if running on
1456 an AMD processor that supports Secure Memory Encryption (SME).
1457
1458 If set to Y, then the encryption of system memory can be
1459 deactivated with the mem_encrypt=off command line option.
1460
1461 If set to N, then the encryption of system memory can be
1462 activated with the mem_encrypt=on command line option.
1463
f88a68fa
TL
1464config ARCH_USE_MEMREMAP_PROT
1465 def_bool y
1466 depends on AMD_MEM_ENCRYPT
1467
506f1d07
SR
1468# Common NUMA Features
1469config NUMA
fd51b2d7 1470 bool "Numa Memory Allocation and Scheduler Support"
506f1d07 1471 depends on SMP
b5660ba7
PA
1472 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1473 default y if X86_BIGSMP
8f9ca475 1474 ---help---
506f1d07 1475 Enable NUMA (Non Uniform Memory Access) support.
fd51b2d7 1476
506f1d07
SR
1477 The kernel will try to allocate memory used by a CPU on the
1478 local memory controller of the CPU and add some more
1479 NUMA awareness to the kernel.
1480
c280ea5e 1481 For 64-bit this is recommended if the system is Intel Core i7
fd51b2d7
KM
1482 (or later), AMD Opteron, or EM64T NUMA.
1483
b5660ba7 1484 For 32-bit this is only needed if you boot a 32-bit
7cf6c945 1485 kernel on a 64-bit NUMA platform.
fd51b2d7
KM
1486
1487 Otherwise, you should say N.
506f1d07 1488
eec1d4fa 1489config AMD_NUMA
3c2362e6
HH
1490 def_bool y
1491 prompt "Old style AMD Opteron NUMA detection"
5da0ef9a 1492 depends on X86_64 && NUMA && PCI
8f9ca475 1493 ---help---
eec1d4fa
HR
1494 Enable AMD NUMA node topology detection. You should say Y here if
1495 you have a multi processor AMD system. This uses an old method to
1496 read the NUMA configuration directly from the builtin Northbridge
1497 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1498 which also takes priority if both are compiled in.
506f1d07
SR
1499
1500config X86_64_ACPI_NUMA
3c2362e6
HH
1501 def_bool y
1502 prompt "ACPI NUMA detection"
506f1d07
SR
1503 depends on X86_64 && NUMA && ACPI && PCI
1504 select ACPI_NUMA
8f9ca475 1505 ---help---
506f1d07
SR
1506 Enable ACPI SRAT based node topology detection.
1507
6ec6e0d9
SS
1508# Some NUMA nodes have memory ranges that span
1509# other nodes. Even though a pfn is valid and
1510# between a node's start and end pfns, it may not
1511# reside on that node. See memmap_init_zone()
1512# for details.
1513config NODES_SPAN_OTHER_NODES
1514 def_bool y
1515 depends on X86_64_ACPI_NUMA
1516
506f1d07
SR
1517config NUMA_EMU
1518 bool "NUMA emulation"
1b7e03ef 1519 depends on NUMA
8f9ca475 1520 ---help---
506f1d07
SR
1521 Enable NUMA emulation. A flat machine will be split
1522 into virtual nodes when booted with "numa=fake=N", where N is the
1523 number of nodes. This is only useful for debugging.
1524
1525config NODES_SHIFT
d25e26b6 1526 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
51591e31
DR
1527 range 1 10
1528 default "10" if MAXSMP
506f1d07 1529 default "6" if X86_64
506f1d07
SR
1530 default "3"
1531 depends on NEED_MULTIPLE_NODES
8f9ca475 1532 ---help---
1184dc2f 1533 Specify the maximum number of NUMA Nodes available on the target
692105b8 1534 system. Increases memory reserved to accommodate various tables.
506f1d07 1535
506f1d07 1536config ARCH_HAVE_MEMORY_PRESENT
3c2362e6 1537 def_bool y
506f1d07 1538 depends on X86_32 && DISCONTIGMEM
506f1d07
SR
1539
1540config NEED_NODE_MEMMAP_SIZE
3c2362e6 1541 def_bool y
506f1d07 1542 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
506f1d07 1543
506f1d07
SR
1544config ARCH_FLATMEM_ENABLE
1545 def_bool y
3b16651f 1546 depends on X86_32 && !NUMA
506f1d07
SR
1547
1548config ARCH_DISCONTIGMEM_ENABLE
1549 def_bool y
b263295d 1550 depends on NUMA && X86_32
506f1d07
SR
1551
1552config ARCH_DISCONTIGMEM_DEFAULT
1553 def_bool y
b263295d
CL
1554 depends on NUMA && X86_32
1555
506f1d07
SR
1556config ARCH_SPARSEMEM_ENABLE
1557 def_bool y
6ea30386 1558 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
506f1d07
SR
1559 select SPARSEMEM_STATIC if X86_32
1560 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1561
3b16651f
TH
1562config ARCH_SPARSEMEM_DEFAULT
1563 def_bool y
1564 depends on X86_64
1565
506f1d07
SR
1566config ARCH_SELECT_MEMORY_MODEL
1567 def_bool y
b263295d 1568 depends on ARCH_SPARSEMEM_ENABLE
506f1d07
SR
1569
1570config ARCH_MEMORY_PROBE
a0842b70 1571 bool "Enable sysfs memory/probe interface"
3120e25e 1572 depends on X86_64 && MEMORY_HOTPLUG
a0842b70
TK
1573 help
1574 This option enables a sysfs memory/probe interface for testing.
1575 See Documentation/memory-hotplug.txt for more information.
1576 If you are unsure how to answer this question, answer N.
506f1d07 1577
3b16651f
TH
1578config ARCH_PROC_KCORE_TEXT
1579 def_bool y
1580 depends on X86_64 && PROC_KCORE
1581
a29815a3
AK
1582config ILLEGAL_POINTER_VALUE
1583 hex
1584 default 0 if X86_32
1585 default 0xdead000000000000 if X86_64
1586
506f1d07
SR
1587source "mm/Kconfig"
1588
7a67832c
DW
1589config X86_PMEM_LEGACY_DEVICE
1590 bool
1591
ec776ef6 1592config X86_PMEM_LEGACY
7a67832c 1593 tristate "Support non-standard NVDIMMs and ADR protected memory"
9f53f9fa
DW
1594 depends on PHYS_ADDR_T_64BIT
1595 depends on BLK_DEV
7a67832c 1596 select X86_PMEM_LEGACY_DEVICE
9f53f9fa 1597 select LIBNVDIMM
ec776ef6
CH
1598 help
1599 Treat memory marked using the non-standard e820 type of 12 as used
1600 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1601 The kernel will offer these regions to the 'pmem' driver so
1602 they can be used for persistent storage.
1603
1604 Say Y if unsure.
1605
506f1d07
SR
1606config HIGHPTE
1607 bool "Allocate 3rd-level pagetables from highmem"
6fc108a0 1608 depends on HIGHMEM
8f9ca475 1609 ---help---
506f1d07
SR
1610 The VM uses one page table entry for each page of physical memory.
1611 For systems with a lot of RAM, this can be wasteful of precious
1612 low memory. Setting this option will put user-space page table
1613 entries in high memory.
1614
9f077871 1615config X86_CHECK_BIOS_CORRUPTION
8f9ca475
IM
1616 bool "Check for low memory corruption"
1617 ---help---
1618 Periodically check for memory corruption in low memory, which
1619 is suspected to be caused by BIOS. Even when enabled in the
1620 configuration, it is disabled at runtime. Enable it by
1621 setting "memory_corruption_check=1" on the kernel command
1622 line. By default it scans the low 64k of memory every 60
1623 seconds; see the memory_corruption_check_size and
1624 memory_corruption_check_period parameters in
8c27ceff 1625 Documentation/admin-guide/kernel-parameters.rst to adjust this.
8f9ca475
IM
1626
1627 When enabled with the default parameters, this option has
1628 almost no overhead, as it reserves a relatively small amount
1629 of memory and scans it infrequently. It both detects corruption
1630 and prevents it from affecting the running system.
1631
1632 It is, however, intended as a diagnostic tool; if repeatable
1633 BIOS-originated corruption always affects the same memory,
1634 you can use memmap= to prevent the kernel from using that
1635 memory.
9f077871 1636
c885df50 1637config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
8f9ca475 1638 bool "Set the default setting of memory_corruption_check"
c885df50
JF
1639 depends on X86_CHECK_BIOS_CORRUPTION
1640 default y
8f9ca475
IM
1641 ---help---
1642 Set whether the default state of memory_corruption_check is
1643 on or off.
c885df50 1644
9ea77bdb 1645config X86_RESERVE_LOW
d0cd7425
PA
1646 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1647 default 64
1648 range 4 640
8f9ca475 1649 ---help---
d0cd7425
PA
1650 Specify the amount of low memory to reserve for the BIOS.
1651
1652 The first page contains BIOS data structures that the kernel
1653 must not use, so that page must always be reserved.
1654
1655 By default we reserve the first 64K of physical RAM, as a
1656 number of BIOSes are known to corrupt that memory range
1657 during events such as suspend/resume or monitor cable
1658 insertion, so it must not be used by the kernel.
fc381519 1659
d0cd7425
PA
1660 You can set this to 4 if you are absolutely sure that you
1661 trust the BIOS to get all its memory reservations and usages
1662 right. If you know your BIOS have problems beyond the
1663 default 64K area, you can set this to 640 to avoid using the
1664 entire low memory range.
fc381519 1665
d0cd7425
PA
1666 If you have doubts about the BIOS (e.g. suspend/resume does
1667 not work or there's kernel crashes after certain hardware
1668 hotplug events) then you might want to enable
1669 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1670 typical corruption patterns.
fc381519 1671
d0cd7425 1672 Leave this to the default value of 64 if you are unsure.
fc381519 1673
506f1d07
SR
1674config MATH_EMULATION
1675 bool
a5b9e5a2 1676 depends on MODIFY_LDT_SYSCALL
506f1d07
SR
1677 prompt "Math emulation" if X86_32
1678 ---help---
1679 Linux can emulate a math coprocessor (used for floating point
1680 operations) if you don't have one. 486DX and Pentium processors have
1681 a math coprocessor built in, 486SX and 386 do not, unless you added
1682 a 487DX or 387, respectively. (The messages during boot time can
1683 give you some hints here ["man dmesg"].) Everyone needs either a
1684 coprocessor or this emulation.
1685
1686 If you don't have a math coprocessor, you need to say Y here; if you
1687 say Y here even though you have a coprocessor, the coprocessor will
1688 be used nevertheless. (This behavior can be changed with the kernel
1689 command line option "no387", which comes handy if your coprocessor
1690 is broken. Try "man bootparam" or see the documentation of your boot
1691 loader (lilo or loadlin) about how to pass options to the kernel at
1692 boot time.) This means that it is a good idea to say Y here if you
1693 intend to use this kernel on different machines.
1694
1695 More information about the internals of the Linux math coprocessor
1696 emulation can be found in <file:arch/x86/math-emu/README>.
1697
1698 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1699 kernel, it won't hurt.
1700
1701config MTRR
6fc108a0 1702 def_bool y
6a108a14 1703 prompt "MTRR (Memory Type Range Register) support" if EXPERT
506f1d07
SR
1704 ---help---
1705 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1706 the Memory Type Range Registers (MTRRs) may be used to control
1707 processor access to memory ranges. This is most useful if you have
1708 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1709 allows bus write transfers to be combined into a larger transfer
1710 before bursting over the PCI/AGP bus. This can increase performance
1711 of image write operations 2.5 times or more. Saying Y here creates a
1712 /proc/mtrr file which may be used to manipulate your processor's
1713 MTRRs. Typically the X server should use this.
1714
1715 This code has a reasonably generic interface so that similar
1716 control registers on other processors can be easily supported
1717 as well:
1718
1719 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1720 Registers (ARRs) which provide a similar functionality to MTRRs. For
1721 these, the ARRs are used to emulate the MTRRs.
1722 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1723 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1724 write-combining. All of these processors are supported by this code
1725 and it makes sense to say Y here if you have one of them.
1726
1727 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1728 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1729 can lead to all sorts of problems, so it's good to say Y here.
1730
1731 You can safely say Y even if your machine doesn't have MTRRs, you'll
1732 just add about 9 KB to your kernel.
1733
7225e751 1734 See <file:Documentation/x86/mtrr.txt> for more information.
506f1d07 1735
95ffa243 1736config MTRR_SANITIZER
2ffb3501 1737 def_bool y
95ffa243
YL
1738 prompt "MTRR cleanup support"
1739 depends on MTRR
8f9ca475 1740 ---help---
aba3728c
TG
1741 Convert MTRR layout from continuous to discrete, so X drivers can
1742 add writeback entries.
95ffa243 1743
aba3728c 1744 Can be disabled with disable_mtrr_cleanup on the kernel command line.
692105b8 1745 The largest mtrr entry size for a continuous block can be set with
aba3728c 1746 mtrr_chunk_size.
95ffa243 1747
2ffb3501 1748 If unsure, say Y.
95ffa243
YL
1749
1750config MTRR_SANITIZER_ENABLE_DEFAULT
f5098d62
YL
1751 int "MTRR cleanup enable value (0-1)"
1752 range 0 1
1753 default "0"
95ffa243 1754 depends on MTRR_SANITIZER
8f9ca475 1755 ---help---
f5098d62 1756 Enable mtrr cleanup default value
95ffa243 1757
12031a62
YL
1758config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1759 int "MTRR cleanup spare reg num (0-7)"
1760 range 0 7
1761 default "1"
1762 depends on MTRR_SANITIZER
8f9ca475 1763 ---help---
12031a62 1764 mtrr cleanup spare entries default, it can be changed via
aba3728c 1765 mtrr_spare_reg_nr=N on the kernel command line.
12031a62 1766
2e5d9c85 1767config X86_PAT
6fc108a0 1768 def_bool y
6a108a14 1769 prompt "x86 PAT support" if EXPERT
2a8a2719 1770 depends on MTRR
8f9ca475 1771 ---help---
2e5d9c85 1772 Use PAT attributes to setup page level cache control.
042b78e4 1773
2e5d9c85 1774 PATs are the modern equivalents of MTRRs and are much more
1775 flexible than MTRRs.
1776
1777 Say N here if you see bootup problems (boot crash, boot hang,
042b78e4 1778 spontaneous reboots) or a non-working video driver.
2e5d9c85 1779
1780 If unsure, say Y.
1781
46cf98cd
VP
1782config ARCH_USES_PG_UNCACHED
1783 def_bool y
1784 depends on X86_PAT
1785
628c6246
PA
1786config ARCH_RANDOM
1787 def_bool y
1788 prompt "x86 architectural random number generator" if EXPERT
1789 ---help---
1790 Enable the x86 architectural RDRAND instruction
1791 (Intel Bull Mountain technology) to generate random numbers.
1792 If supported, this is a high bandwidth, cryptographically
1793 secure hardware random number generator.
1794
51ae4a2d
PA
1795config X86_SMAP
1796 def_bool y
1797 prompt "Supervisor Mode Access Prevention" if EXPERT
1798 ---help---
1799 Supervisor Mode Access Prevention (SMAP) is a security
1800 feature in newer Intel processors. There is a small
1801 performance cost if this enabled and turned on; there is
1802 also a small increase in the kernel size if this is enabled.
1803
1804 If unsure, say Y.
1805
aa35f896 1806config X86_INTEL_UMIP
796ebc81 1807 def_bool y
aa35f896
RN
1808 depends on CPU_SUP_INTEL
1809 prompt "Intel User Mode Instruction Prevention" if EXPERT
1810 ---help---
1811 The User Mode Instruction Prevention (UMIP) is a security
1812 feature in newer Intel processors. If enabled, a general
796ebc81
RN
1813 protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1814 or STR instructions are executed in user mode. These instructions
1815 unnecessarily expose information about the hardware state.
1816
1817 The vast majority of applications do not use these instructions.
1818 For the very few that do, software emulation is provided in
1819 specific cases in protected and virtual-8086 modes. Emulated
1820 results are dummy.
aa35f896 1821
72e9b5fe
DH
1822config X86_INTEL_MPX
1823 prompt "Intel MPX (Memory Protection Extensions)"
1824 def_bool n
df3735c5
RR
1825 # Note: only available in 64-bit mode due to VMA flags shortage
1826 depends on CPU_SUP_INTEL && X86_64
1827 select ARCH_USES_HIGH_VMA_FLAGS
72e9b5fe
DH
1828 ---help---
1829 MPX provides hardware features that can be used in
1830 conjunction with compiler-instrumented code to check
1831 memory references. It is designed to detect buffer
1832 overflow or underflow bugs.
1833
1834 This option enables running applications which are
1835 instrumented or otherwise use MPX. It does not use MPX
1836 itself inside the kernel or to protect the kernel
1837 against bad memory references.
1838
1839 Enabling this option will make the kernel larger:
1840 ~8k of kernel text and 36 bytes of data on a 64-bit
1841 defconfig. It adds a long to the 'mm_struct' which
1842 will increase the kernel memory overhead of each
1843 process and adds some branches to paths used during
1844 exec() and munmap().
1845
1846 For details, see Documentation/x86/intel_mpx.txt
1847
1848 If unsure, say N.
1849
35e97790 1850config X86_INTEL_MEMORY_PROTECTION_KEYS
284244a9 1851 prompt "Intel Memory Protection Keys"
35e97790 1852 def_bool y
284244a9 1853 # Note: only available in 64-bit mode
35e97790 1854 depends on CPU_SUP_INTEL && X86_64
52c8e601
IM
1855 select ARCH_USES_HIGH_VMA_FLAGS
1856 select ARCH_HAS_PKEYS
284244a9
DH
1857 ---help---
1858 Memory Protection Keys provides a mechanism for enforcing
1859 page-based protections, but without requiring modification of the
1860 page tables when an application changes protection domains.
1861
1862 For details, see Documentation/x86/protection-keys.txt
1863
1864 If unsure, say y.
35e97790 1865
506f1d07 1866config EFI
9ba16087 1867 bool "EFI runtime service support"
5b83683f 1868 depends on ACPI
f6ce5002 1869 select UCS2_STRING
022ee6c5 1870 select EFI_RUNTIME_WRAPPERS
506f1d07 1871 ---help---
8f9ca475
IM
1872 This enables the kernel to use EFI runtime services that are
1873 available (such as the EFI variable services).
506f1d07 1874
8f9ca475
IM
1875 This option is only useful on systems that have EFI firmware.
1876 In addition, you should use the latest ELILO loader available
1877 at <http://elilo.sourceforge.net> in order to take advantage
1878 of EFI runtime services. However, even with this option, the
1879 resultant kernel should continue to boot on existing non-EFI
1880 platforms.
506f1d07 1881
291f3632
MF
1882config EFI_STUB
1883 bool "EFI stub support"
b16d8c23 1884 depends on EFI && !X86_USE_3DNOW
7b2a583a 1885 select RELOCATABLE
291f3632
MF
1886 ---help---
1887 This kernel feature allows a bzImage to be loaded directly
1888 by EFI firmware without the use of a bootloader.
1889
4172fe2f 1890 See Documentation/efi-stub.txt for more information.
0c759662 1891
7d453eee
MF
1892config EFI_MIXED
1893 bool "EFI mixed-mode support"
1894 depends on EFI_STUB && X86_64
1895 ---help---
1896 Enabling this feature allows a 64-bit kernel to be booted
1897 on a 32-bit firmware, provided that your CPU supports 64-bit
1898 mode.
1899
1900 Note that it is not possible to boot a mixed-mode enabled
1901 kernel via the EFI boot stub - a bootloader that supports
1902 the EFI handover protocol must be used.
1903
1904 If unsure, say N.
1905
506f1d07 1906config SECCOMP
3c2362e6
HH
1907 def_bool y
1908 prompt "Enable seccomp to safely compute untrusted bytecode"
8f9ca475 1909 ---help---
506f1d07
SR
1910 This kernel feature is useful for number crunching applications
1911 that may need to compute untrusted bytecode during their
1912 execution. By using pipes or other transports made available to
1913 the process as file descriptors supporting the read/write
1914 syscalls, it's possible to isolate those applications in
1915 their own address space using seccomp. Once seccomp is
9c0bbee8 1916 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
506f1d07
SR
1917 and the task is only allowed to execute a few safe syscalls
1918 defined by each seccomp mode.
1919
1920 If unsure, say Y. Only embedded should say N here.
1921
506f1d07
SR
1922source kernel/Kconfig.hz
1923
1924config KEXEC
1925 bool "kexec system call"
2965faa5 1926 select KEXEC_CORE
8f9ca475 1927 ---help---
506f1d07
SR
1928 kexec is a system call that implements the ability to shutdown your
1929 current kernel, and to start another kernel. It is like a reboot
1930 but it is independent of the system firmware. And like a reboot
1931 you can start any kernel with it, not just Linux.
1932
1933 The name comes from the similarity to the exec system call.
1934
1935 It is an ongoing process to be certain the hardware in a machine
1936 is properly shutdown, so do not be surprised if this code does not
bf220695
GU
1937 initially work for you. As of this writing the exact hardware
1938 interface is strongly in flux, so no good recommendation can be
1939 made.
506f1d07 1940
74ca317c
VG
1941config KEXEC_FILE
1942 bool "kexec file based system call"
2965faa5 1943 select KEXEC_CORE
74ca317c 1944 select BUILD_BIN2C
74ca317c
VG
1945 depends on X86_64
1946 depends on CRYPTO=y
1947 depends on CRYPTO_SHA256=y
1948 ---help---
1949 This is new version of kexec system call. This system call is
1950 file based and takes file descriptors as system call argument
1951 for kernel and initramfs as opposed to list of segments as
1952 accepted by previous system call.
1953
8e7d8381
VG
1954config KEXEC_VERIFY_SIG
1955 bool "Verify kernel signature during kexec_file_load() syscall"
74ca317c 1956 depends on KEXEC_FILE
8e7d8381
VG
1957 ---help---
1958 This option makes kernel signature verification mandatory for
d8eb8940
BP
1959 the kexec_file_load() syscall.
1960
1961 In addition to that option, you need to enable signature
1962 verification for the corresponding kernel image type being
1963 loaded in order for this to work.
8e7d8381
VG
1964
1965config KEXEC_BZIMAGE_VERIFY_SIG
1966 bool "Enable bzImage signature verification support"
1967 depends on KEXEC_VERIFY_SIG
1968 depends on SIGNED_PE_FILE_VERIFICATION
1969 select SYSTEM_TRUSTED_KEYRING
1970 ---help---
1971 Enable bzImage signature verification support.
1972
506f1d07 1973config CRASH_DUMP
04b69447 1974 bool "kernel crash dumps"
506f1d07 1975 depends on X86_64 || (X86_32 && HIGHMEM)
8f9ca475 1976 ---help---
506f1d07
SR
1977 Generate crash dump after being started by kexec.
1978 This should be normally only set in special crash dump kernels
1979 which are loaded in the main kernel with kexec-tools into
1980 a specially reserved region and then later executed after
1981 a crash by kdump/kexec. The crash dump kernel must be compiled
1982 to a memory address not used by the main kernel or BIOS using
1983 PHYSICAL_START, or it must be built as a relocatable image
1984 (CONFIG_RELOCATABLE=y).
1985 For more details see Documentation/kdump/kdump.txt
1986
3ab83521 1987config KEXEC_JUMP
6ea30386 1988 bool "kexec jump"
fee7b0d8 1989 depends on KEXEC && HIBERNATION
8f9ca475 1990 ---help---
89081d17
HY
1991 Jump between original kernel and kexeced kernel and invoke
1992 code in physical address mode via KEXEC
3ab83521 1993
506f1d07 1994config PHYSICAL_START
6a108a14 1995 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
ceefccc9 1996 default "0x1000000"
8f9ca475 1997 ---help---
506f1d07
SR
1998 This gives the physical address where the kernel is loaded.
1999
2000 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2001 bzImage will decompress itself to above physical address and
2002 run from there. Otherwise, bzImage will run from the address where
2003 it has been loaded by the boot loader and will ignore above physical
2004 address.
2005
2006 In normal kdump cases one does not have to set/change this option
2007 as now bzImage can be compiled as a completely relocatable image
2008 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2009 address. This option is mainly useful for the folks who don't want
2010 to use a bzImage for capturing the crash dump and want to use a
2011 vmlinux instead. vmlinux is not relocatable hence a kernel needs
2012 to be specifically compiled to run from a specific memory area
2013 (normally a reserved region) and this option comes handy.
2014
ceefccc9
PA
2015 So if you are using bzImage for capturing the crash dump,
2016 leave the value here unchanged to 0x1000000 and set
2017 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
2018 for capturing the crash dump change this value to start of
2019 the reserved region. In other words, it can be set based on
2020 the "X" value as specified in the "crashkernel=YM@XM"
2021 command line boot parameter passed to the panic-ed
2022 kernel. Please take a look at Documentation/kdump/kdump.txt
2023 for more details about crash dumps.
506f1d07
SR
2024
2025 Usage of bzImage for capturing the crash dump is recommended as
2026 one does not have to build two kernels. Same kernel can be used
2027 as production kernel and capture kernel. Above option should have
2028 gone away after relocatable bzImage support is introduced. But it
2029 is present because there are users out there who continue to use
2030 vmlinux for dump capture. This option should go away down the
2031 line.
2032
2033 Don't change this unless you know what you are doing.
2034
2035config RELOCATABLE
26717808
PA
2036 bool "Build a relocatable kernel"
2037 default y
8f9ca475 2038 ---help---
506f1d07
SR
2039 This builds a kernel image that retains relocation information
2040 so it can be loaded someplace besides the default 1MB.
2041 The relocations tend to make the kernel binary about 10% larger,
2042 but are discarded at runtime.
2043
2044 One use is for the kexec on panic case where the recovery kernel
2045 must live at a different physical address than the primary
2046 kernel.
2047
2048 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2049 it has been loaded at and the compile time physical address
8ab3820f 2050 (CONFIG_PHYSICAL_START) is used as the minimum location.
506f1d07 2051
8ab3820f 2052config RANDOMIZE_BASE
e8581e3d 2053 bool "Randomize the address of the kernel image (KASLR)"
8ab3820f 2054 depends on RELOCATABLE
6807c846 2055 default y
8ab3820f 2056 ---help---
e8581e3d
BH
2057 In support of Kernel Address Space Layout Randomization (KASLR),
2058 this randomizes the physical address at which the kernel image
2059 is decompressed and the virtual address where the kernel
2060 image is mapped, as a security feature that deters exploit
2061 attempts relying on knowledge of the location of kernel
2062 code internals.
2063
ed9f007e
KC
2064 On 64-bit, the kernel physical and virtual addresses are
2065 randomized separately. The physical address will be anywhere
2066 between 16MB and the top of physical memory (up to 64TB). The
2067 virtual address will be randomized from 16MB up to 1GB (9 bits
2068 of entropy). Note that this also reduces the memory space
2069 available to kernel modules from 1.5GB to 1GB.
2070
2071 On 32-bit, the kernel physical and virtual addresses are
2072 randomized together. They will be randomized from 16MB up to
2073 512MB (8 bits of entropy).
e8581e3d
BH
2074
2075 Entropy is generated using the RDRAND instruction if it is
2076 supported. If RDTSC is supported, its value is mixed into
2077 the entropy pool as well. If neither RDRAND nor RDTSC are
ed9f007e
KC
2078 supported, then entropy is read from the i8254 timer. The
2079 usable entropy is limited by the kernel being built using
2080 2GB addressing, and that PHYSICAL_ALIGN must be at a
2081 minimum of 2MB. As a result, only 10 bits of entropy are
2082 theoretically possible, but the implementations are further
2083 limited due to memory layouts.
e8581e3d 2084
6807c846 2085 If unsure, say Y.
8ab3820f
KC
2086
2087# Relocation on x86 needs some additional build support
845adf72
PA
2088config X86_NEED_RELOCS
2089 def_bool y
8ab3820f 2090 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
845adf72 2091
506f1d07 2092config PHYSICAL_ALIGN
a0215061 2093 hex "Alignment value to which kernel should be aligned"
8ab3820f 2094 default "0x200000"
a0215061
KC
2095 range 0x2000 0x1000000 if X86_32
2096 range 0x200000 0x1000000 if X86_64
8f9ca475 2097 ---help---
506f1d07
SR
2098 This value puts the alignment restrictions on physical address
2099 where kernel is loaded and run from. Kernel is compiled for an
2100 address which meets above alignment restriction.
2101
2102 If bootloader loads the kernel at a non-aligned address and
2103 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2104 address aligned to above value and run from there.
2105
2106 If bootloader loads the kernel at a non-aligned address and
2107 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2108 load address and decompress itself to the address it has been
2109 compiled for and run from there. The address for which kernel is
2110 compiled already meets above alignment restrictions. Hence the
2111 end result is that kernel runs from a physical address meeting
2112 above alignment restrictions.
2113
a0215061
KC
2114 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2115 this value must be a multiple of 0x200000.
2116
506f1d07
SR
2117 Don't change this unless you know what you are doing.
2118
0483e1fa
TG
2119config RANDOMIZE_MEMORY
2120 bool "Randomize the kernel memory sections"
2121 depends on X86_64
2122 depends on RANDOMIZE_BASE
2123 default RANDOMIZE_BASE
2124 ---help---
2125 Randomizes the base virtual address of kernel memory sections
2126 (physical memory mapping, vmalloc & vmemmap). This security feature
2127 makes exploits relying on predictable memory locations less reliable.
2128
2129 The order of allocations remains unchanged. Entropy is generated in
2130 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2131 configuration have in average 30,000 different possible virtual
2132 addresses for each memory section.
2133
6807c846 2134 If unsure, say Y.
0483e1fa 2135
90397a41
TG
2136config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2137 hex "Physical memory mapping padding" if EXPERT
2138 depends on RANDOMIZE_MEMORY
2139 default "0xa" if MEMORY_HOTPLUG
2140 default "0x0"
2141 range 0x1 0x40 if MEMORY_HOTPLUG
2142 range 0x0 0x40
2143 ---help---
2144 Define the padding in terabytes added to the existing physical
2145 memory size during kernel memory randomization. It is useful
2146 for memory hotplug support but reduces the entropy available for
2147 address randomization.
2148
2149 If unsure, leave at the default value.
2150
506f1d07 2151config HOTPLUG_CPU
7c13e6a3 2152 bool "Support for hot-pluggable CPUs"
40b31360 2153 depends on SMP
506f1d07 2154 ---help---
7c13e6a3
DS
2155 Say Y here to allow turning CPUs off and on. CPUs can be
2156 controlled through /sys/devices/system/cpu.
2157 ( Note: power management support will enable this option
2158 automatically on SMP systems. )
2159 Say N if you want to disable CPU hotplug.
506f1d07 2160
80aa1dff
FY
2161config BOOTPARAM_HOTPLUG_CPU0
2162 bool "Set default setting of cpu0_hotpluggable"
2163 default n
2c922cd0 2164 depends on HOTPLUG_CPU
80aa1dff
FY
2165 ---help---
2166 Set whether default state of cpu0_hotpluggable is on or off.
2167
2168 Say Y here to enable CPU0 hotplug by default. If this switch
2169 is turned on, there is no need to give cpu0_hotplug kernel
2170 parameter and the CPU0 hotplug feature is enabled by default.
2171
2172 Please note: there are two known CPU0 dependencies if you want
2173 to enable the CPU0 hotplug feature either by this switch or by
2174 cpu0_hotplug kernel parameter.
2175
2176 First, resume from hibernate or suspend always starts from CPU0.
2177 So hibernate and suspend are prevented if CPU0 is offline.
2178
2179 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2180 offline if any interrupt can not migrate out of CPU0. There may
2181 be other CPU0 dependencies.
2182
2183 Please make sure the dependencies are under your control before
2184 you enable this feature.
2185
2186 Say N if you don't want to enable CPU0 hotplug feature by default.
2187 You still can enable the CPU0 hotplug feature at boot by kernel
2188 parameter cpu0_hotplug.
2189
a71c8bc5
FY
2190config DEBUG_HOTPLUG_CPU0
2191 def_bool n
2192 prompt "Debug CPU0 hotplug"
2c922cd0 2193 depends on HOTPLUG_CPU
a71c8bc5
FY
2194 ---help---
2195 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2196 soon as possible and boots up userspace with CPU0 offlined. User
2197 can online CPU0 back after boot time.
2198
2199 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2200 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2201 compilation or giving cpu0_hotplug kernel parameter at boot.
2202
2203 If unsure, say N.
2204
506f1d07 2205config COMPAT_VDSO
b0b49f26
AL
2206 def_bool n
2207 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
953fee1d 2208 depends on COMPAT_32
8f9ca475 2209 ---help---
b0b49f26
AL
2210 Certain buggy versions of glibc will crash if they are
2211 presented with a 32-bit vDSO that is not mapped at the address
2212 indicated in its segment table.
e84446de 2213
b0b49f26
AL
2214 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2215 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2216 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2217 the only released version with the bug, but OpenSUSE 9
2218 contains a buggy "glibc 2.3.2".
506f1d07 2219
b0b49f26
AL
2220 The symptom of the bug is that everything crashes on startup, saying:
2221 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2222
2223 Saying Y here changes the default value of the vdso32 boot
2224 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2225 This works around the glibc bug but hurts performance.
2226
2227 If unsure, say N: if you are compiling your own kernel, you
2228 are unlikely to be using a buggy version of glibc.
506f1d07 2229
3dc33bd3
KC
2230choice
2231 prompt "vsyscall table for legacy applications"
2232 depends on X86_64
2233 default LEGACY_VSYSCALL_EMULATE
2234 help
2235 Legacy user code that does not know how to find the vDSO expects
2236 to be able to issue three syscalls by calling fixed addresses in
2237 kernel space. Since this location is not randomized with ASLR,
2238 it can be used to assist security vulnerability exploitation.
2239
2240 This setting can be changed at boot time via the kernel command
2241 line parameter vsyscall=[native|emulate|none].
2242
2243 On a system with recent enough glibc (2.14 or newer) and no
2244 static binaries, you can say None without a performance penalty
2245 to improve security.
2246
2247 If unsure, select "Emulate".
2248
2249 config LEGACY_VSYSCALL_NATIVE
2250 bool "Native"
2251 help
2252 Actual executable code is located in the fixed vsyscall
2253 address mapping, implementing time() efficiently. Since
2254 this makes the mapping executable, it can be used during
2255 security vulnerability exploitation (traditionally as
2256 ROP gadgets). This configuration is not recommended.
2257
2258 config LEGACY_VSYSCALL_EMULATE
2259 bool "Emulate"
2260 help
2261 The kernel traps and emulates calls into the fixed
2262 vsyscall address mapping. This makes the mapping
2263 non-executable, but it still contains known contents,
2264 which could be used in certain rare security vulnerability
2265 exploits. This configuration is recommended when userspace
2266 still uses the vsyscall area.
2267
2268 config LEGACY_VSYSCALL_NONE
2269 bool "None"
2270 help
2271 There will be no vsyscall mapping at all. This will
2272 eliminate any risk of ASLR bypass due to the vsyscall
2273 fixed address mapping. Attempts to use the vsyscalls
2274 will be reported to dmesg, so that either old or
2275 malicious userspace programs can be identified.
2276
2277endchoice
2278
516cbf37
TB
2279config CMDLINE_BOOL
2280 bool "Built-in kernel command line"
8f9ca475 2281 ---help---
516cbf37
TB
2282 Allow for specifying boot arguments to the kernel at
2283 build time. On some systems (e.g. embedded ones), it is
2284 necessary or convenient to provide some or all of the
2285 kernel boot arguments with the kernel itself (that is,
2286 to not rely on the boot loader to provide them.)
2287
2288 To compile command line arguments into the kernel,
2289 set this option to 'Y', then fill in the
69711ca1 2290 boot arguments in CONFIG_CMDLINE.
516cbf37
TB
2291
2292 Systems with fully functional boot loaders (i.e. non-embedded)
2293 should leave this option set to 'N'.
2294
2295config CMDLINE
2296 string "Built-in kernel command string"
2297 depends on CMDLINE_BOOL
2298 default ""
8f9ca475 2299 ---help---
516cbf37
TB
2300 Enter arguments here that should be compiled into the kernel
2301 image and used at boot time. If the boot loader provides a
2302 command line at boot time, it is appended to this string to
2303 form the full kernel command line, when the system boots.
2304
2305 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2306 change this behavior.
2307
2308 In most cases, the command line (whether built-in or provided
2309 by the boot loader) should specify the device for the root
2310 file system.
2311
2312config CMDLINE_OVERRIDE
2313 bool "Built-in command line overrides boot loader arguments"
516cbf37 2314 depends on CMDLINE_BOOL
8f9ca475 2315 ---help---
516cbf37
TB
2316 Set this option to 'Y' to have the kernel ignore the boot loader
2317 command line, and use ONLY the built-in command line.
2318
2319 This is used to work around broken boot loaders. This should
2320 be set to 'N' under normal conditions.
2321
a5b9e5a2
AL
2322config MODIFY_LDT_SYSCALL
2323 bool "Enable the LDT (local descriptor table)" if EXPERT
2324 default y
2325 ---help---
2326 Linux can allow user programs to install a per-process x86
2327 Local Descriptor Table (LDT) using the modify_ldt(2) system
2328 call. This is required to run 16-bit or segmented code such as
2329 DOSEMU or some Wine programs. It is also used by some very old
2330 threading libraries.
2331
2332 Enabling this feature adds a small amount of overhead to
2333 context switches and increases the low-level kernel attack
2334 surface. Disabling it removes the modify_ldt(2) system call.
2335
2336 Saying 'N' here may make sense for embedded or server kernels.
2337
b700e7f0
SJ
2338source "kernel/livepatch/Kconfig"
2339
506f1d07
SR
2340endmenu
2341
3072e413
MH
2342config ARCH_HAS_ADD_PAGES
2343 def_bool y
2344 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2345
506f1d07
SR
2346config ARCH_ENABLE_MEMORY_HOTPLUG
2347 def_bool y
2348 depends on X86_64 || (X86_32 && HIGHMEM)
2349
35551053
GH
2350config ARCH_ENABLE_MEMORY_HOTREMOVE
2351 def_bool y
2352 depends on MEMORY_HOTPLUG
2353
e534c7c5 2354config USE_PERCPU_NUMA_NODE_ID
645a7919 2355 def_bool y
e534c7c5
LS
2356 depends on NUMA
2357
9491846f
KS
2358config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2359 def_bool y
2360 depends on X86_64 || X86_PAE
2361
c177c81e
NH
2362config ARCH_ENABLE_HUGEPAGE_MIGRATION
2363 def_bool y
2364 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2365
9c670ea3
NH
2366config ARCH_ENABLE_THP_MIGRATION
2367 def_bool y
2368 depends on X86_64 && TRANSPARENT_HUGEPAGE
2369
da85f865 2370menu "Power management and ACPI options"
e279b6c1
SR
2371
2372config ARCH_HIBERNATION_HEADER
3c2362e6 2373 def_bool y
e279b6c1 2374 depends on X86_64 && HIBERNATION
e279b6c1
SR
2375
2376source "kernel/power/Kconfig"
2377
2378source "drivers/acpi/Kconfig"
2379
efafc8b2
FT
2380source "drivers/sfi/Kconfig"
2381
a6b68076 2382config X86_APM_BOOT
6fc108a0 2383 def_bool y
282e5aab 2384 depends on APM
a6b68076 2385
e279b6c1
SR
2386menuconfig APM
2387 tristate "APM (Advanced Power Management) BIOS support"
efefa6f6 2388 depends on X86_32 && PM_SLEEP
e279b6c1
SR
2389 ---help---
2390 APM is a BIOS specification for saving power using several different
2391 techniques. This is mostly useful for battery powered laptops with
2392 APM compliant BIOSes. If you say Y here, the system time will be
2393 reset after a RESUME operation, the /proc/apm device will provide
2394 battery status information, and user-space programs will receive
2395 notification of APM "events" (e.g. battery status change).
2396
2397 If you select "Y" here, you can disable actual use of the APM
2398 BIOS by passing the "apm=off" option to the kernel at boot time.
2399
2400 Note that the APM support is almost completely disabled for
2401 machines with more than one CPU.
2402
2403 In order to use APM, you will need supporting software. For location
2dc98fd3
MW
2404 and more information, read <file:Documentation/power/apm-acpi.txt>
2405 and the Battery Powered Linux mini-HOWTO, available from
e279b6c1
SR
2406 <http://www.tldp.org/docs.html#howto>.
2407
2408 This driver does not spin down disk drives (see the hdparm(8)
2409 manpage ("man 8 hdparm") for that), and it doesn't turn off
2410 VESA-compliant "green" monitors.
2411
2412 This driver does not support the TI 4000M TravelMate and the ACER
2413 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2414 desktop machines also don't have compliant BIOSes, and this driver
2415 may cause those machines to panic during the boot phase.
2416
2417 Generally, if you don't have a battery in your machine, there isn't
2418 much point in using this driver and you should say N. If you get
2419 random kernel OOPSes or reboots that don't seem to be related to
2420 anything, try disabling/enabling this option (or disabling/enabling
2421 APM in your BIOS).
2422
2423 Some other things you should try when experiencing seemingly random,
2424 "weird" problems:
2425
2426 1) make sure that you have enough swap space and that it is
2427 enabled.
2428 2) pass the "no-hlt" option to the kernel
2429 3) switch on floating point emulation in the kernel and pass
2430 the "no387" option to the kernel
2431 4) pass the "floppy=nodma" option to the kernel
2432 5) pass the "mem=4M" option to the kernel (thereby disabling
2433 all but the first 4 MB of RAM)
2434 6) make sure that the CPU is not over clocked.
2435 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2436 8) disable the cache from your BIOS settings
2437 9) install a fan for the video card or exchange video RAM
2438 10) install a better fan for the CPU
2439 11) exchange RAM chips
2440 12) exchange the motherboard.
2441
2442 To compile this driver as a module, choose M here: the
2443 module will be called apm.
2444
2445if APM
2446
2447config APM_IGNORE_USER_SUSPEND
2448 bool "Ignore USER SUSPEND"
8f9ca475 2449 ---help---
e279b6c1
SR
2450 This option will ignore USER SUSPEND requests. On machines with a
2451 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2452 series notebooks, it is necessary to say Y because of a BIOS bug.
2453
2454config APM_DO_ENABLE
2455 bool "Enable PM at boot time"
2456 ---help---
2457 Enable APM features at boot time. From page 36 of the APM BIOS
2458 specification: "When disabled, the APM BIOS does not automatically
2459 power manage devices, enter the Standby State, enter the Suspend
2460 State, or take power saving steps in response to CPU Idle calls."
2461 This driver will make CPU Idle calls when Linux is idle (unless this
2462 feature is turned off -- see "Do CPU IDLE calls", below). This
2463 should always save battery power, but more complicated APM features
2464 will be dependent on your BIOS implementation. You may need to turn
2465 this option off if your computer hangs at boot time when using APM
2466 support, or if it beeps continuously instead of suspending. Turn
2467 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2468 T400CDT. This is off by default since most machines do fine without
2469 this feature.
2470
2471config APM_CPU_IDLE
dd8af076 2472 depends on CPU_IDLE
e279b6c1 2473 bool "Make CPU Idle calls when idle"
8f9ca475 2474 ---help---
e279b6c1
SR
2475 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2476 On some machines, this can activate improved power savings, such as
2477 a slowed CPU clock rate, when the machine is idle. These idle calls
2478 are made after the idle loop has run for some length of time (e.g.,
2479 333 mS). On some machines, this will cause a hang at boot time or
2480 whenever the CPU becomes idle. (On machines with more than one CPU,
2481 this option does nothing.)
2482
2483config APM_DISPLAY_BLANK
2484 bool "Enable console blanking using APM"
8f9ca475 2485 ---help---
e279b6c1
SR
2486 Enable console blanking using the APM. Some laptops can use this to
2487 turn off the LCD backlight when the screen blanker of the Linux
2488 virtual console blanks the screen. Note that this is only used by
2489 the virtual console screen blanker, and won't turn off the backlight
2490 when using the X Window system. This also doesn't have anything to
2491 do with your VESA-compliant power-saving monitor. Further, this
2492 option doesn't work for all laptops -- it might not turn off your
2493 backlight at all, or it might print a lot of errors to the console,
2494 especially if you are using gpm.
2495
2496config APM_ALLOW_INTS
2497 bool "Allow interrupts during APM BIOS calls"
8f9ca475 2498 ---help---
e279b6c1
SR
2499 Normally we disable external interrupts while we are making calls to
2500 the APM BIOS as a measure to lessen the effects of a badly behaving
2501 BIOS implementation. The BIOS should reenable interrupts if it
2502 needs to. Unfortunately, some BIOSes do not -- especially those in
2503 many of the newer IBM Thinkpads. If you experience hangs when you
2504 suspend, try setting this to Y. Otherwise, say N.
2505
e279b6c1
SR
2506endif # APM
2507
bb0a56ec 2508source "drivers/cpufreq/Kconfig"
e279b6c1
SR
2509
2510source "drivers/cpuidle/Kconfig"
2511
27471fdb
AH
2512source "drivers/idle/Kconfig"
2513
e279b6c1
SR
2514endmenu
2515
2516
2517menu "Bus options (PCI etc.)"
2518
2519config PCI
1ac97018 2520 bool "PCI support"
1c858087 2521 default y
8f9ca475 2522 ---help---
e279b6c1
SR
2523 Find out whether you have a PCI motherboard. PCI is the name of a
2524 bus system, i.e. the way the CPU talks to the other stuff inside
2525 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2526 VESA. If you have PCI, say Y, otherwise N.
2527
e279b6c1
SR
2528choice
2529 prompt "PCI access mode"
efefa6f6 2530 depends on X86_32 && PCI
e279b6c1
SR
2531 default PCI_GOANY
2532 ---help---
2533 On PCI systems, the BIOS can be used to detect the PCI devices and
2534 determine their configuration. However, some old PCI motherboards
2535 have BIOS bugs and may crash if this is done. Also, some embedded
2536 PCI-based systems don't have any BIOS at all. Linux can also try to
2537 detect the PCI hardware directly without using the BIOS.
2538
2539 With this option, you can specify how Linux should detect the
2540 PCI devices. If you choose "BIOS", the BIOS will be used,
2541 if you choose "Direct", the BIOS won't be used, and if you
2542 choose "MMConfig", then PCI Express MMCONFIG will be used.
2543 If you choose "Any", the kernel will try MMCONFIG, then the
2544 direct access method and falls back to the BIOS if that doesn't
2545 work. If unsure, go with the default, which is "Any".
2546
2547config PCI_GOBIOS
2548 bool "BIOS"
2549
2550config PCI_GOMMCONFIG
2551 bool "MMConfig"
2552
2553config PCI_GODIRECT
2554 bool "Direct"
2555
3ef0e1f8 2556config PCI_GOOLPC
76fb6570 2557 bool "OLPC XO-1"
3ef0e1f8
AS
2558 depends on OLPC
2559
2bdd1b03
AS
2560config PCI_GOANY
2561 bool "Any"
2562
e279b6c1
SR
2563endchoice
2564
2565config PCI_BIOS
3c2362e6 2566 def_bool y
efefa6f6 2567 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
e279b6c1
SR
2568
2569# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2570config PCI_DIRECT
3c2362e6 2571 def_bool y
0aba496f 2572 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
e279b6c1
SR
2573
2574config PCI_MMCONFIG
3c2362e6 2575 def_bool y
5f0db7a2 2576 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
e279b6c1 2577
3ef0e1f8 2578config PCI_OLPC
2bdd1b03
AS
2579 def_bool y
2580 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
3ef0e1f8 2581
b5401a96
AN
2582config PCI_XEN
2583 def_bool y
2584 depends on PCI && XEN
2585 select SWIOTLB_XEN
2586
e279b6c1 2587config PCI_DOMAINS
3c2362e6 2588 def_bool y
e279b6c1 2589 depends on PCI
e279b6c1
SR
2590
2591config PCI_MMCONFIG
2592 bool "Support mmconfig PCI config space access"
2593 depends on X86_64 && PCI && ACPI
2594
3f6ea84a 2595config PCI_CNB20LE_QUIRK
6a108a14 2596 bool "Read CNB20LE Host Bridge Windows" if EXPERT
6ea30386 2597 depends on PCI
3f6ea84a
IS
2598 help
2599 Read the PCI windows out of the CNB20LE host bridge. This allows
2600 PCI hotplug to work on systems with the CNB20LE chipset which do
2601 not have ACPI.
2602
64a5fed6
BH
2603 There's no public spec for this chipset, and this functionality
2604 is known to be incomplete.
2605
2606 You should say N unless you know you need this.
2607
e279b6c1
SR
2608source "drivers/pci/Kconfig"
2609
3a495511
WBG
2610config ISA_BUS
2611 bool "ISA-style bus support on modern systems" if EXPERT
2612 select ISA_BUS_API
2613 help
2614 Enables ISA-style drivers on modern systems. This is necessary to
2615 support PC/104 devices on X86_64 platforms.
2616
2617 If unsure, say N.
2618
1c00f016 2619# x86_64 have no ISA slots, but can have ISA-style DMA.
e279b6c1 2620config ISA_DMA_API
1c00f016
DR
2621 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2622 default y
2623 help
2624 Enables ISA-style DMA support for devices requiring such controllers.
2625 If unsure, say Y.
e279b6c1 2626
51e68d05
LT
2627if X86_32
2628
e279b6c1
SR
2629config ISA
2630 bool "ISA support"
8f9ca475 2631 ---help---
e279b6c1
SR
2632 Find out whether you have ISA slots on your motherboard. ISA is the
2633 name of a bus system, i.e. the way the CPU talks to the other stuff
2634 inside your box. Other bus systems are PCI, EISA, MicroChannel
2635 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2636 newer boards don't support it. If you have ISA, say Y, otherwise N.
2637
2638config EISA
2639 bool "EISA support"
2640 depends on ISA
2641 ---help---
2642 The Extended Industry Standard Architecture (EISA) bus was
2643 developed as an open alternative to the IBM MicroChannel bus.
2644
2645 The EISA bus provided some of the features of the IBM MicroChannel
2646 bus while maintaining backward compatibility with cards made for
2647 the older ISA bus. The EISA bus saw limited use between 1988 and
2648 1995 when it was made obsolete by the PCI bus.
2649
2650 Say Y here if you are building a kernel for an EISA-based machine.
2651
2652 Otherwise, say N.
2653
2654source "drivers/eisa/Kconfig"
2655
e279b6c1
SR
2656config SCx200
2657 tristate "NatSemi SCx200 support"
8f9ca475 2658 ---help---
e279b6c1
SR
2659 This provides basic support for National Semiconductor's
2660 (now AMD's) Geode processors. The driver probes for the
2661 PCI-IDs of several on-chip devices, so its a good dependency
2662 for other scx200_* drivers.
2663
2664 If compiled as a module, the driver is named scx200.
2665
2666config SCx200HR_TIMER
2667 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
592913ec 2668 depends on SCx200
e279b6c1 2669 default y
8f9ca475 2670 ---help---
e279b6c1
SR
2671 This driver provides a clocksource built upon the on-chip
2672 27MHz high-resolution timer. Its also a workaround for
2673 NSC Geode SC-1100's buggy TSC, which loses time when the
2674 processor goes idle (as is done by the scheduler). The
2675 other workaround is idle=poll boot option.
2676
3ef0e1f8
AS
2677config OLPC
2678 bool "One Laptop Per Child support"
54008979 2679 depends on !X86_PAE
3c554946 2680 select GPIOLIB
dc3119e7 2681 select OF
45bb1674 2682 select OF_PROMTREE
b4e51854 2683 select IRQ_DOMAIN
8f9ca475 2684 ---help---
3ef0e1f8
AS
2685 Add support for detecting the unique features of the OLPC
2686 XO hardware.
2687
a3128588
DD
2688config OLPC_XO1_PM
2689 bool "OLPC XO-1 Power Management"
97c4cb71 2690 depends on OLPC && MFD_CS5535 && PM_SLEEP
a3128588 2691 select MFD_CORE
bf1ebf00 2692 ---help---
97c4cb71 2693 Add support for poweroff and suspend of the OLPC XO-1 laptop.
bf1ebf00 2694
cfee9597
DD
2695config OLPC_XO1_RTC
2696 bool "OLPC XO-1 Real Time Clock"
2697 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2698 ---help---
2699 Add support for the XO-1 real time clock, which can be used as a
2700 programmable wakeup source.
2701
7feda8e9
DD
2702config OLPC_XO1_SCI
2703 bool "OLPC XO-1 SCI extras"
d8d01a63 2704 depends on OLPC && OLPC_XO1_PM
ed8e47fe 2705 depends on INPUT=y
d8d01a63 2706 select POWER_SUPPLY
7feda8e9
DD
2707 select GPIO_CS5535
2708 select MFD_CORE
2709 ---help---
2710 Add support for SCI-based features of the OLPC XO-1 laptop:
7bc74b3d 2711 - EC-driven system wakeups
7feda8e9 2712 - Power button
7bc74b3d 2713 - Ebook switch
2cf2baea 2714 - Lid switch
e1040ac6
DD
2715 - AC adapter status updates
2716 - Battery status updates
7feda8e9 2717
a0f30f59
DD
2718config OLPC_XO15_SCI
2719 bool "OLPC XO-1.5 SCI extras"
d8d01a63
DD
2720 depends on OLPC && ACPI
2721 select POWER_SUPPLY
a0f30f59
DD
2722 ---help---
2723 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2724 - EC-driven system wakeups
2725 - AC adapter status updates
2726 - Battery status updates
bf1ebf00 2727
d4f3e350
EW
2728config ALIX
2729 bool "PCEngines ALIX System Support (LED setup)"
2730 select GPIOLIB
2731 ---help---
2732 This option enables system support for the PCEngines ALIX.
2733 At present this just sets up LEDs for GPIO control on
2734 ALIX2/3/6 boards. However, other system specific setup should
2735 get added here.
2736
2737 Note: You must still enable the drivers for GPIO and LED support
2738 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2739
2740 Note: You have to set alix.force=1 for boards with Award BIOS.
2741
da4e3302
PP
2742config NET5501
2743 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2744 select GPIOLIB
2745 ---help---
2746 This option enables system support for the Soekris Engineering net5501.
2747
3197059a
PP
2748config GEOS
2749 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2750 select GPIOLIB
2751 depends on DMI
2752 ---help---
2753 This option enables system support for the Traverse Technologies GEOS.
2754
7d029125
VD
2755config TS5500
2756 bool "Technologic Systems TS-5500 platform support"
2757 depends on MELAN
2758 select CHECK_SIGNATURE
2759 select NEW_LEDS
2760 select LEDS_CLASS
2761 ---help---
2762 This option enables system support for the Technologic Systems TS-5500.
2763
bc0120fd
SR
2764endif # X86_32
2765
23ac4ae8 2766config AMD_NB
e279b6c1 2767 def_bool y
0e152cd7 2768 depends on CPU_SUP_AMD && PCI
e279b6c1
SR
2769
2770source "drivers/pcmcia/Kconfig"
2771
388b78ad 2772config RAPIDIO
fdf90abc 2773 tristate "RapidIO support"
388b78ad
AB
2774 depends on PCI
2775 default n
2776 help
fdf90abc 2777 If enabled this option will include drivers and the core
388b78ad
AB
2778 infrastructure code to support RapidIO interconnect devices.
2779
2780source "drivers/rapidio/Kconfig"
2781
e3263ab3
DH
2782config X86_SYSFB
2783 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2784 help
2785 Firmwares often provide initial graphics framebuffers so the BIOS,
2786 bootloader or kernel can show basic video-output during boot for
2787 user-guidance and debugging. Historically, x86 used the VESA BIOS
2788 Extensions and EFI-framebuffers for this, which are mostly limited
2789 to x86.
2790 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2791 framebuffers so the new generic system-framebuffer drivers can be
2792 used on x86. If the framebuffer is not compatible with the generic
2793 modes, it is adverticed as fallback platform framebuffer so legacy
2794 drivers like efifb, vesafb and uvesafb can pick it up.
2795 If this option is not selected, all system framebuffers are always
2796 marked as fallback platform framebuffers as usual.
2797
2798 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2799 not be able to pick up generic system framebuffers if this option
2800 is selected. You are highly encouraged to enable simplefb as
2801 replacement if you select this option. simplefb can correctly deal
2802 with generic system framebuffers. But you should still keep vesafb
2803 and others enabled as fallback if a system framebuffer is
2804 incompatible with simplefb.
2805
2806 If unsure, say Y.
2807
e279b6c1
SR
2808endmenu
2809
2810
2811menu "Executable file formats / Emulations"
2812
2813source "fs/Kconfig.binfmt"
2814
2815config IA32_EMULATION
2816 bool "IA32 Emulation"
2817 depends on X86_64
39f88911 2818 select ARCH_WANT_OLD_COMPAT_IPC
d1603990 2819 select BINFMT_ELF
a97f52e6 2820 select COMPAT_BINFMT_ELF
39f88911 2821 select COMPAT_OLD_SIGACTION
8f9ca475 2822 ---help---
5fd92e65
L
2823 Include code to run legacy 32-bit programs under a
2824 64-bit kernel. You should likely turn this on, unless you're
2825 100% sure that you don't have any 32-bit programs left.
e279b6c1
SR
2826
2827config IA32_AOUT
8f9ca475
IM
2828 tristate "IA32 a.out support"
2829 depends on IA32_EMULATION
2830 ---help---
2831 Support old a.out binaries in the 32bit emulation.
e279b6c1 2832
0bf62763 2833config X86_X32
6ea30386 2834 bool "x32 ABI for 64-bit mode"
9b54050b 2835 depends on X86_64
5fd92e65
L
2836 ---help---
2837 Include code to run binaries for the x32 native 32-bit ABI
2838 for 64-bit processors. An x32 process gets access to the
2839 full 64-bit register file and wide data path while leaving
2840 pointers at 32 bits for smaller memory footprint.
2841
2842 You will need a recent binutils (2.22 or later) with
2843 elf32_x86_64 support enabled to compile a kernel with this
2844 option set.
2845
953fee1d
IM
2846config COMPAT_32
2847 def_bool y
2848 depends on IA32_EMULATION || X86_32
2849 select HAVE_UID16
2850 select OLD_SIGSUSPEND3
2851
e279b6c1 2852config COMPAT
3c2362e6 2853 def_bool y
0bf62763 2854 depends on IA32_EMULATION || X86_X32
e279b6c1 2855
3120e25e 2856if COMPAT
e279b6c1 2857config COMPAT_FOR_U64_ALIGNMENT
3120e25e 2858 def_bool y
e279b6c1
SR
2859
2860config SYSVIPC_COMPAT
3c2362e6 2861 def_bool y
3120e25e 2862 depends on SYSVIPC
3120e25e 2863endif
ee009e4a 2864
e279b6c1
SR
2865endmenu
2866
2867
e5beae16
KP
2868config HAVE_ATOMIC_IOMAP
2869 def_bool y
2870 depends on X86_32
2871
4692d77f
AR
2872config X86_DEV_DMA_OPS
2873 bool
83125a3a 2874 depends on X86_64 || STA2X11
4692d77f 2875
f7219a53
AR
2876config X86_DMA_REMAP
2877 bool
83125a3a 2878 depends on STA2X11
f7219a53 2879
e585513b
KS
2880config HAVE_GENERIC_GUP
2881 def_bool y
2882
e279b6c1
SR
2883source "net/Kconfig"
2884
2885source "drivers/Kconfig"
2886
2887source "drivers/firmware/Kconfig"
2888
2889source "fs/Kconfig"
2890
e279b6c1
SR
2891source "arch/x86/Kconfig.debug"
2892
2893source "security/Kconfig"
2894
2895source "crypto/Kconfig"
2896
edf88417
AK
2897source "arch/x86/kvm/Kconfig"
2898
e279b6c1 2899source "lib/Kconfig"